qemu-e2k/blockdev.c

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/*
* QEMU host block devices
*
* Copyright (c) 2003-2008 Fabrice Bellard
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*
* This file incorporates work covered by the following copyright and
* permission notice:
*
* Copyright (c) 2003-2008 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
block: New BlockBackend A block device consists of a frontend device model and a backend. A block backend has a tree of block drivers doing the actual work. The tree is managed by the block layer. We currently use a single abstraction BlockDriverState both for tree nodes and the backend as a whole. Drawbacks: * Its API includes both stuff that makes sense only at the block backend level (root of the tree) and stuff that's only for use within the block layer. This makes the API bigger and more complex than necessary. Moreover, it's not obvious which interfaces are meant for device models, and which really aren't. * Since device models keep a reference to their backend, the backend object can't just be destroyed. But for media change, we need to replace the tree. Our solution is to make the BlockDriverState generic, with actual driver state in a separate object, pointed to by member opaque. That lets us replace the tree by deinitializing and reinitializing its root. This special need of the root makes the data structure awkward everywhere in the tree. The general plan is to separate the APIs into "block backend", for use by device models, monitor and whatever other code dealing with block backends, and "block driver", for use by the block layer and whatever other code (if any) dealing with trees and tree nodes. Code dealing with block backends, device models in particular, should become completely oblivious of BlockDriverState. This should let us clean up both APIs, and the tree data structures. This commit is a first step. It creates a minimal "block backend" API: type BlockBackend and functions to create, destroy and find them. BlockBackend objects are created and destroyed exactly when root BlockDriverState objects are created and destroyed. "Root" in the sense of "in bdrv_states". They're not yet used for anything; that'll come shortly. A root BlockDriverState is created with bdrv_new_root(), so where to create a BlockBackend is obvious. Where these roots get destroyed isn't always as obvious. It is obvious in qemu-img.c, qemu-io.c and qemu-nbd.c, and in error paths of blockdev_init(), blk_connect(). That leaves destruction of objects successfully created by blockdev_init() and blk_connect(). blockdev_init() is used only by drive_new() and qmp_blockdev_add(). Objects created by the latter are currently indestructible (see commit 48f364d "blockdev: Refuse to drive_del something added with blockdev-add" and commit 2d246f0 "blockdev: Introduce DriveInfo.enable_auto_del"). Objects created by the former get destroyed by drive_del(). Objects created by blk_connect() get destroyed by blk_disconnect(). BlockBackend is reference-counted. Its reference count never exceeds one so far, but that's going to change. In drive_del(), the BB's reference count is surely one now. The BDS's reference count is greater than one when something else is holding a reference, such as a block job. In this case, the BB is destroyed right away, but the BDS lives on until all extra references get dropped. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-07 13:59:04 +02:00
#include "sysemu/block-backend.h"
#include "sysemu/blockdev.h"
#include "hw/block/block.h"
#include "block/blockjob.h"
#include "block/throttle-groups.h"
#include "monitor/monitor.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "qapi/qmp/types.h"
#include "qapi-visit.h"
#include "qapi/qmp/qerror.h"
#include "qapi/qobject-output-visitor.h"
#include "qapi/util.h"
#include "sysemu/sysemu.h"
#include "block/block_int.h"
#include "qmp-commands.h"
#include "block/trace.h"
#include "sysemu/arch_init.h"
#include "qemu/cutils.h"
#include "qemu/help_option.h"
#include "qemu/throttle-options.h"
static QTAILQ_HEAD(, BlockDriverState) monitor_bdrv_states =
QTAILQ_HEAD_INITIALIZER(monitor_bdrv_states);
static int do_open_tray(const char *blk_name, const char *qdev_id,
bool force, Error **errp);
static const char *const if_name[IF_COUNT] = {
[IF_NONE] = "none",
[IF_IDE] = "ide",
[IF_SCSI] = "scsi",
[IF_FLOPPY] = "floppy",
[IF_PFLASH] = "pflash",
[IF_MTD] = "mtd",
[IF_SD] = "sd",
[IF_VIRTIO] = "virtio",
[IF_XEN] = "xen",
};
static int if_max_devs[IF_COUNT] = {
/*
* Do not change these numbers! They govern how drive option
* index maps to unit and bus. That mapping is ABI.
*
* All controllers used to implement if=T drives need to support
* if_max_devs[T] units, for any T with if_max_devs[T] != 0.
* Otherwise, some index values map to "impossible" bus, unit
* values.
*
* For instance, if you change [IF_SCSI] to 255, -drive
* if=scsi,index=12 no longer means bus=1,unit=5, but
* bus=0,unit=12. With an lsi53c895a controller (7 units max),
* the drive can't be set up. Regression.
*/
[IF_IDE] = 2,
[IF_SCSI] = 7,
};
/**
* Boards may call this to offer board-by-board overrides
* of the default, global values.
*/
void override_max_devs(BlockInterfaceType type, int max_devs)
{
BlockBackend *blk;
DriveInfo *dinfo;
if (max_devs <= 0) {
return;
}
for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
dinfo = blk_legacy_dinfo(blk);
if (dinfo->type == type) {
fprintf(stderr, "Cannot override units-per-bus property of"
" the %s interface, because a drive of that type has"
" already been added.\n", if_name[type]);
g_assert_not_reached();
}
}
if_max_devs[type] = max_devs;
}
/*
* We automatically delete the drive when a device using it gets
* unplugged. Questionable feature, but we can't just drop it.
* Device models call blockdev_mark_auto_del() to schedule the
* automatic deletion, and generic qdev code calls blockdev_auto_del()
* when deletion is actually safe.
*/
void blockdev_mark_auto_del(BlockBackend *blk)
{
DriveInfo *dinfo = blk_legacy_dinfo(blk);
BlockDriverState *bs = blk_bs(blk);
AioContext *aio_context;
if (!dinfo) {
return;
}
if (bs) {
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (bs->job) {
block_job_cancel(bs->job);
}
aio_context_release(aio_context);
}
dinfo->auto_del = 1;
}
void blockdev_auto_del(BlockBackend *blk)
{
DriveInfo *dinfo = blk_legacy_dinfo(blk);
if (dinfo && dinfo->auto_del) {
monitor_remove_blk(blk);
blk_unref(blk);
}
}
/**
* Returns the current mapping of how many units per bus
* a particular interface can support.
*
* A positive integer indicates n units per bus.
* 0 implies the mapping has not been established.
* -1 indicates an invalid BlockInterfaceType was given.
*/
int drive_get_max_devs(BlockInterfaceType type)
{
if (type >= IF_IDE && type < IF_COUNT) {
return if_max_devs[type];
}
return -1;
}
static int drive_index_to_bus_id(BlockInterfaceType type, int index)
{
int max_devs = if_max_devs[type];
return max_devs ? index / max_devs : 0;
}
static int drive_index_to_unit_id(BlockInterfaceType type, int index)
{
int max_devs = if_max_devs[type];
return max_devs ? index % max_devs : index;
}
QemuOpts *drive_def(const char *optstr)
{
QemuOpts: Wean off qerror_report_err() qerror_report_err() is a transitional interface to help with converting existing monitor commands to QMP. It should not be used elsewhere. The only remaining user in qemu-option.c is qemu_opts_parse(). Is it used in QMP context? If not, we can simply replace qerror_report_err() by error_report_err(). The uses in qemu-img.c, qemu-io.c, qemu-nbd.c and under tests/ are clearly not in QMP context. The uses in vl.c aren't either, because the only QMP command handlers there are qmp_query_status() and qmp_query_machines(), and they don't call it. Remaining uses: * drive_def(): Command line -drive and such, HMP drive_add and pci_add * hmp_chardev_add(): HMP chardev-add * monitor_parse_command(): HMP core * tmp_config_parse(): Command line -tpmdev * net_host_device_add(): HMP host_net_add * net_client_parse(): Command line -net and -netdev * qemu_global_option(): Command line -global * vnc_parse_func(): Command line -display, -vnc, default display, HMP change, QMP change. Bummer. * qemu_pci_hot_add_nic(): HMP pci_add * usb_net_init(): Command line -usbdevice, HMP usb_add Propagate errors through qemu_opts_parse(). Create a convenience function qemu_opts_parse_noisily() that passes errors to error_report_err(). Switch all non-QMP users outside tests to it. That leaves vnc_parse_func(). Propagate errors through it. Since I'm touching it anyway, rename it to vnc_parse(). Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-02-13 12:50:26 +01:00
return qemu_opts_parse_noisily(qemu_find_opts("drive"), optstr, false);
}
QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
const char *optstr)
{
QemuOpts *opts;
opts = drive_def(optstr);
if (!opts) {
return NULL;
}
if (type != IF_DEFAULT) {
qemu_opt_set(opts, "if", if_name[type], &error_abort);
}
if (index >= 0) {
qemu_opt_set_number(opts, "index", index, &error_abort);
}
if (file)
qemu_opt_set(opts, "file", file, &error_abort);
return opts;
}
DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
{
BlockBackend *blk;
DriveInfo *dinfo;
for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
dinfo = blk_legacy_dinfo(blk);
if (dinfo && dinfo->type == type
&& dinfo->bus == bus && dinfo->unit == unit) {
return dinfo;
}
}
return NULL;
}
void drive_check_orphaned(void)
{
BlockBackend *blk;
DriveInfo *dinfo;
Location loc;
bool orphans = false;
for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
dinfo = blk_legacy_dinfo(blk);
if (!blk_get_attached_dev(blk) && !dinfo->is_default &&
dinfo->type != IF_NONE) {
loc_push_none(&loc);
qemu_opts_loc_restore(dinfo->opts);
error_report("machine type does not support"
" if=%s,bus=%d,unit=%d",
if_name[dinfo->type], dinfo->bus, dinfo->unit);
loc_pop(&loc);
orphans = true;
}
}
if (orphans) {
exit(1);
}
}
DriveInfo *drive_get_by_index(BlockInterfaceType type, int index)
{
return drive_get(type,
drive_index_to_bus_id(type, index),
drive_index_to_unit_id(type, index));
}
int drive_get_max_bus(BlockInterfaceType type)
{
int max_bus;
BlockBackend *blk;
DriveInfo *dinfo;
max_bus = -1;
for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
dinfo = blk_legacy_dinfo(blk);
if (dinfo && dinfo->type == type && dinfo->bus > max_bus) {
max_bus = dinfo->bus;
}
}
return max_bus;
}
/* Get a block device. This should only be used for single-drive devices
(e.g. SD/Floppy/MTD). Multi-disk devices (scsi/ide) should use the
appropriate bus. */
DriveInfo *drive_get_next(BlockInterfaceType type)
{
static int next_block_unit[IF_COUNT];
return drive_get(type, 0, next_block_unit[type]++);
}
static void bdrv_format_print(void *opaque, const char *name)
{
error_printf(" %s", name);
}
typedef struct {
QEMUBH *bh;
BlockDriverState *bs;
} BDRVPutRefBH;
static int parse_block_error_action(const char *buf, bool is_read, Error **errp)
{
if (!strcmp(buf, "ignore")) {
return BLOCKDEV_ON_ERROR_IGNORE;
} else if (!is_read && !strcmp(buf, "enospc")) {
return BLOCKDEV_ON_ERROR_ENOSPC;
} else if (!strcmp(buf, "stop")) {
return BLOCKDEV_ON_ERROR_STOP;
} else if (!strcmp(buf, "report")) {
return BLOCKDEV_ON_ERROR_REPORT;
} else {
error_setg(errp, "'%s' invalid %s error action",
buf, is_read ? "read" : "write");
return -1;
}
}
static bool parse_stats_intervals(BlockAcctStats *stats, QList *intervals,
Error **errp)
{
const QListEntry *entry;
for (entry = qlist_first(intervals); entry; entry = qlist_next(entry)) {
switch (qobject_type(entry->value)) {
case QTYPE_QSTRING: {
unsigned long long length;
const char *str = qstring_get_str(qobject_to_qstring(entry->value));
if (parse_uint_full(str, &length, 10) == 0 &&
length > 0 && length <= UINT_MAX) {
block_acct_add_interval(stats, (unsigned) length);
} else {
error_setg(errp, "Invalid interval length: %s", str);
return false;
}
break;
}
case QTYPE_QNUM: {
int64_t length = qnum_get_int(qobject_to_qnum(entry->value));
if (length > 0 && length <= UINT_MAX) {
block_acct_add_interval(stats, (unsigned) length);
} else {
error_setg(errp, "Invalid interval length: %" PRId64, length);
return false;
}
break;
}
default:
error_setg(errp, "The specification of stats-intervals is invalid");
return false;
}
}
return true;
}
typedef enum { MEDIA_DISK, MEDIA_CDROM } DriveMediaType;
/* All parameters but @opts are optional and may be set to NULL. */
static void extract_common_blockdev_options(QemuOpts *opts, int *bdrv_flags,
const char **throttling_group, ThrottleConfig *throttle_cfg,
BlockdevDetectZeroesOptions *detect_zeroes, Error **errp)
{
Error *local_error = NULL;
const char *aio;
if (bdrv_flags) {
if (qemu_opt_get_bool(opts, "copy-on-read", false)) {
*bdrv_flags |= BDRV_O_COPY_ON_READ;
}
if ((aio = qemu_opt_get(opts, "aio")) != NULL) {
if (!strcmp(aio, "native")) {
*bdrv_flags |= BDRV_O_NATIVE_AIO;
} else if (!strcmp(aio, "threads")) {
/* this is the default */
} else {
error_setg(errp, "invalid aio option");
return;
}
}
}
/* disk I/O throttling */
if (throttling_group) {
*throttling_group = qemu_opt_get(opts, "throttling.group");
}
if (throttle_cfg) {
throttle_config_init(throttle_cfg);
throttle_cfg->buckets[THROTTLE_BPS_TOTAL].avg =
qemu_opt_get_number(opts, "throttling.bps-total", 0);
throttle_cfg->buckets[THROTTLE_BPS_READ].avg =
qemu_opt_get_number(opts, "throttling.bps-read", 0);
throttle_cfg->buckets[THROTTLE_BPS_WRITE].avg =
qemu_opt_get_number(opts, "throttling.bps-write", 0);
throttle_cfg->buckets[THROTTLE_OPS_TOTAL].avg =
qemu_opt_get_number(opts, "throttling.iops-total", 0);
throttle_cfg->buckets[THROTTLE_OPS_READ].avg =
qemu_opt_get_number(opts, "throttling.iops-read", 0);
throttle_cfg->buckets[THROTTLE_OPS_WRITE].avg =
qemu_opt_get_number(opts, "throttling.iops-write", 0);
throttle_cfg->buckets[THROTTLE_BPS_TOTAL].max =
qemu_opt_get_number(opts, "throttling.bps-total-max", 0);
throttle_cfg->buckets[THROTTLE_BPS_READ].max =
qemu_opt_get_number(opts, "throttling.bps-read-max", 0);
throttle_cfg->buckets[THROTTLE_BPS_WRITE].max =
qemu_opt_get_number(opts, "throttling.bps-write-max", 0);
throttle_cfg->buckets[THROTTLE_OPS_TOTAL].max =
qemu_opt_get_number(opts, "throttling.iops-total-max", 0);
throttle_cfg->buckets[THROTTLE_OPS_READ].max =
qemu_opt_get_number(opts, "throttling.iops-read-max", 0);
throttle_cfg->buckets[THROTTLE_OPS_WRITE].max =
qemu_opt_get_number(opts, "throttling.iops-write-max", 0);
throttle_cfg->buckets[THROTTLE_BPS_TOTAL].burst_length =
qemu_opt_get_number(opts, "throttling.bps-total-max-length", 1);
throttle_cfg->buckets[THROTTLE_BPS_READ].burst_length =
qemu_opt_get_number(opts, "throttling.bps-read-max-length", 1);
throttle_cfg->buckets[THROTTLE_BPS_WRITE].burst_length =
qemu_opt_get_number(opts, "throttling.bps-write-max-length", 1);
throttle_cfg->buckets[THROTTLE_OPS_TOTAL].burst_length =
qemu_opt_get_number(opts, "throttling.iops-total-max-length", 1);
throttle_cfg->buckets[THROTTLE_OPS_READ].burst_length =
qemu_opt_get_number(opts, "throttling.iops-read-max-length", 1);
throttle_cfg->buckets[THROTTLE_OPS_WRITE].burst_length =
qemu_opt_get_number(opts, "throttling.iops-write-max-length", 1);
throttle_cfg->op_size =
qemu_opt_get_number(opts, "throttling.iops-size", 0);
if (!throttle_is_valid(throttle_cfg, errp)) {
return;
}
}
if (detect_zeroes) {
*detect_zeroes =
qapi_enum_parse(BlockdevDetectZeroesOptions_lookup,
qemu_opt_get(opts, "detect-zeroes"),
BLOCKDEV_DETECT_ZEROES_OPTIONS__MAX,
BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
&local_error);
if (local_error) {
error_propagate(errp, local_error);
return;
}
}
}
/* Takes the ownership of bs_opts */
static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
Error **errp)
{
const char *buf;
int bdrv_flags = 0;
int on_read_error, on_write_error;
bool account_invalid, account_failed;
bool writethrough, read_only;
block: New BlockBackend A block device consists of a frontend device model and a backend. A block backend has a tree of block drivers doing the actual work. The tree is managed by the block layer. We currently use a single abstraction BlockDriverState both for tree nodes and the backend as a whole. Drawbacks: * Its API includes both stuff that makes sense only at the block backend level (root of the tree) and stuff that's only for use within the block layer. This makes the API bigger and more complex than necessary. Moreover, it's not obvious which interfaces are meant for device models, and which really aren't. * Since device models keep a reference to their backend, the backend object can't just be destroyed. But for media change, we need to replace the tree. Our solution is to make the BlockDriverState generic, with actual driver state in a separate object, pointed to by member opaque. That lets us replace the tree by deinitializing and reinitializing its root. This special need of the root makes the data structure awkward everywhere in the tree. The general plan is to separate the APIs into "block backend", for use by device models, monitor and whatever other code dealing with block backends, and "block driver", for use by the block layer and whatever other code (if any) dealing with trees and tree nodes. Code dealing with block backends, device models in particular, should become completely oblivious of BlockDriverState. This should let us clean up both APIs, and the tree data structures. This commit is a first step. It creates a minimal "block backend" API: type BlockBackend and functions to create, destroy and find them. BlockBackend objects are created and destroyed exactly when root BlockDriverState objects are created and destroyed. "Root" in the sense of "in bdrv_states". They're not yet used for anything; that'll come shortly. A root BlockDriverState is created with bdrv_new_root(), so where to create a BlockBackend is obvious. Where these roots get destroyed isn't always as obvious. It is obvious in qemu-img.c, qemu-io.c and qemu-nbd.c, and in error paths of blockdev_init(), blk_connect(). That leaves destruction of objects successfully created by blockdev_init() and blk_connect(). blockdev_init() is used only by drive_new() and qmp_blockdev_add(). Objects created by the latter are currently indestructible (see commit 48f364d "blockdev: Refuse to drive_del something added with blockdev-add" and commit 2d246f0 "blockdev: Introduce DriveInfo.enable_auto_del"). Objects created by the former get destroyed by drive_del(). Objects created by blk_connect() get destroyed by blk_disconnect(). BlockBackend is reference-counted. Its reference count never exceeds one so far, but that's going to change. In drive_del(), the BB's reference count is surely one now. The BDS's reference count is greater than one when something else is holding a reference, such as a block job. In this case, the BB is destroyed right away, but the BDS lives on until all extra references get dropped. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-07 13:59:04 +02:00
BlockBackend *blk;
BlockDriverState *bs;
ThrottleConfig cfg;
int snapshot = 0;
Error *error = NULL;
QemuOpts *opts;
QDict *interval_dict = NULL;
QList *interval_list = NULL;
const char *id;
BlockdevDetectZeroesOptions detect_zeroes =
BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
const char *throttling_group = NULL;
/* Check common options by copying from bs_opts to opts, all other options
* stay in bs_opts for processing by bdrv_open(). */
id = qdict_get_try_str(bs_opts, "id");
opts = qemu_opts_create(&qemu_common_drive_opts, id, 1, &error);
if (error) {
error_propagate(errp, error);
goto err_no_opts;
}
qemu_opts_absorb_qdict(opts, bs_opts, &error);
if (error) {
error_propagate(errp, error);
goto early_err;
}
if (id) {
qdict_del(bs_opts, "id");
}
/* extract parameters */
snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
account_invalid = qemu_opt_get_bool(opts, "stats-account-invalid", true);
account_failed = qemu_opt_get_bool(opts, "stats-account-failed", true);
writethrough = !qemu_opt_get_bool(opts, BDRV_OPT_CACHE_WB, true);
id = qemu_opts_id(opts);
qdict_extract_subqdict(bs_opts, &interval_dict, "stats-intervals.");
qdict_array_split(interval_dict, &interval_list);
if (qdict_size(interval_dict) != 0) {
error_setg(errp, "Invalid option stats-intervals.%s",
qdict_first(interval_dict)->key);
goto early_err;
}
extract_common_blockdev_options(opts, &bdrv_flags, &throttling_group, &cfg,
&detect_zeroes, &error);
if (error) {
error_propagate(errp, error);
goto early_err;
}
if ((buf = qemu_opt_get(opts, "format")) != NULL) {
if (is_help_option(buf)) {
error_printf("Supported formats:");
bdrv_iterate_format(bdrv_format_print, NULL);
error_printf("\n");
goto early_err;
}
if (qdict_haskey(bs_opts, "driver")) {
error_setg(errp, "Cannot specify both 'driver' and 'format'");
goto early_err;
}
qdict_put_str(bs_opts, "driver", buf);
}
on_write_error = BLOCKDEV_ON_ERROR_ENOSPC;
if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
on_write_error = parse_block_error_action(buf, 0, &error);
if (error) {
error_propagate(errp, error);
goto early_err;
}
}
on_read_error = BLOCKDEV_ON_ERROR_REPORT;
if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
on_read_error = parse_block_error_action(buf, 1, &error);
if (error) {
error_propagate(errp, error);
goto early_err;
}
}
if (snapshot) {
bdrv_flags |= BDRV_O_SNAPSHOT;
}
read_only = qemu_opt_get_bool(opts, BDRV_OPT_READ_ONLY, false);
/* init */
if ((!file || !*file) && !qdict_size(bs_opts)) {
BlockBackendRootState *blk_rs;
blk = blk_new(0, BLK_PERM_ALL);
blk_rs = blk_get_root_state(blk);
blk_rs->open_flags = bdrv_flags;
blk_rs->read_only = read_only;
blk_rs->detect_zeroes = detect_zeroes;
QDECREF(bs_opts);
} else {
if (file && !*file) {
file = NULL;
}
/* bdrv_open() defaults to the values in bdrv_flags (for compatibility
* with other callers) rather than what we want as the real defaults.
* Apply the defaults here instead. */
qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY,
read_only ? "on" : "off");
assert((bdrv_flags & BDRV_O_CACHE_MASK) == 0);
if (runstate_check(RUN_STATE_INMIGRATE)) {
bdrv_flags |= BDRV_O_INACTIVE;
}
blk = blk_new_open(file, NULL, bs_opts, bdrv_flags, errp);
if (!blk) {
goto err_no_bs_opts;
}
bs = blk_bs(blk);
bs->detect_zeroes = detect_zeroes;
if (bdrv_key_required(bs)) {
autostart = 0;
}
block_acct_setup(blk_get_stats(blk), account_invalid, account_failed);
if (!parse_stats_intervals(blk_get_stats(blk), interval_list, errp)) {
blk_unref(blk);
blk = NULL;
goto err_no_bs_opts;
}
}
/* disk I/O throttling */
if (throttle_enabled(&cfg)) {
if (!throttling_group) {
throttling_group = id;
}
blk_io_limits_enable(blk, throttling_group);
blk_set_io_limits(blk, &cfg);
}
blk_set_enable_write_cache(blk, !writethrough);
blk_set_on_error(blk, on_read_error, on_write_error);
if (!monitor_add_blk(blk, id, errp)) {
blk_unref(blk);
blk = NULL;
goto err_no_bs_opts;
}
err_no_bs_opts:
qemu_opts_del(opts);
QDECREF(interval_dict);
QDECREF(interval_list);
return blk;
early_err:
qemu_opts_del(opts);
QDECREF(interval_dict);
QDECREF(interval_list);
err_no_opts:
QDECREF(bs_opts);
return NULL;
}
/* Takes the ownership of bs_opts */
static BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp)
{
int bdrv_flags = 0;
/* bdrv_open() defaults to the values in bdrv_flags (for compatibility
* with other callers) rather than what we want as the real defaults.
* Apply the defaults here instead. */
qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY, "off");
if (runstate_check(RUN_STATE_INMIGRATE)) {
bdrv_flags |= BDRV_O_INACTIVE;
}
return bdrv_open(NULL, NULL, bs_opts, bdrv_flags, errp);
}
void blockdev_close_all_bdrv_states(void)
{
BlockDriverState *bs, *next_bs;
QTAILQ_FOREACH_SAFE(bs, &monitor_bdrv_states, monitor_list, next_bs) {
AioContext *ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
bdrv_unref(bs);
aio_context_release(ctx);
}
}
/* Iterates over the list of monitor-owned BlockDriverStates */
BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs)
{
return bs ? QTAILQ_NEXT(bs, monitor_list)
: QTAILQ_FIRST(&monitor_bdrv_states);
}
static void qemu_opt_rename(QemuOpts *opts, const char *from, const char *to,
Error **errp)
{
const char *value;
value = qemu_opt_get(opts, from);
if (value) {
if (qemu_opt_find(opts, to)) {
error_setg(errp, "'%s' and its alias '%s' can't be used at the "
"same time", to, from);
return;
}
}
/* rename all items in opts */
while ((value = qemu_opt_get(opts, from))) {
qemu_opt_set(opts, to, value, &error_abort);
qemu_opt_unset(opts, from);
}
}
QemuOptsList qemu_legacy_drive_opts = {
.name = "drive",
.head = QTAILQ_HEAD_INITIALIZER(qemu_legacy_drive_opts.head),
.desc = {
{
.name = "bus",
.type = QEMU_OPT_NUMBER,
.help = "bus number",
},{
.name = "unit",
.type = QEMU_OPT_NUMBER,
.help = "unit number (i.e. lun for scsi)",
},{
.name = "index",
.type = QEMU_OPT_NUMBER,
.help = "index number",
},{
.name = "media",
.type = QEMU_OPT_STRING,
.help = "media type (disk, cdrom)",
},{
.name = "if",
.type = QEMU_OPT_STRING,
.help = "interface (ide, scsi, sd, mtd, floppy, pflash, virtio)",
},{
.name = "cyls",
.type = QEMU_OPT_NUMBER,
.help = "number of cylinders (ide disk geometry)",
},{
.name = "heads",
.type = QEMU_OPT_NUMBER,
.help = "number of heads (ide disk geometry)",
},{
.name = "secs",
.type = QEMU_OPT_NUMBER,
.help = "number of sectors (ide disk geometry)",
},{
.name = "trans",
.type = QEMU_OPT_STRING,
.help = "chs translation (auto, lba, none)",
},{
.name = "boot",
.type = QEMU_OPT_BOOL,
.help = "(deprecated, ignored)",
},{
.name = "addr",
.type = QEMU_OPT_STRING,
.help = "pci address (virtio only)",
},{
.name = "serial",
.type = QEMU_OPT_STRING,
.help = "disk serial number",
},{
.name = "file",
.type = QEMU_OPT_STRING,
.help = "file name",
},
/* Options that are passed on, but have special semantics with -drive */
{
.name = BDRV_OPT_READ_ONLY,
.type = QEMU_OPT_BOOL,
.help = "open drive file as read-only",
},{
.name = "rerror",
.type = QEMU_OPT_STRING,
.help = "read error action",
},{
.name = "werror",
.type = QEMU_OPT_STRING,
.help = "write error action",
},{
.name = "copy-on-read",
.type = QEMU_OPT_BOOL,
.help = "copy read data from backing file into image file",
},
{ /* end of list */ }
},
};
DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type)
{
const char *value;
BlockBackend *blk;
DriveInfo *dinfo = NULL;
QDict *bs_opts;
QemuOpts *legacy_opts;
DriveMediaType media = MEDIA_DISK;
BlockInterfaceType type;
int cyls, heads, secs, translation;
int max_devs, bus_id, unit_id, index;
const char *devaddr;
const char *werror, *rerror;
bool read_only = false;
bool copy_on_read;
const char *serial;
const char *filename;
Error *local_err = NULL;
int i;
/* Change legacy command line options into QMP ones */
static const struct {
const char *from;
const char *to;
} opt_renames[] = {
{ "iops", "throttling.iops-total" },
{ "iops_rd", "throttling.iops-read" },
{ "iops_wr", "throttling.iops-write" },
{ "bps", "throttling.bps-total" },
{ "bps_rd", "throttling.bps-read" },
{ "bps_wr", "throttling.bps-write" },
{ "iops_max", "throttling.iops-total-max" },
{ "iops_rd_max", "throttling.iops-read-max" },
{ "iops_wr_max", "throttling.iops-write-max" },
{ "bps_max", "throttling.bps-total-max" },
{ "bps_rd_max", "throttling.bps-read-max" },
{ "bps_wr_max", "throttling.bps-write-max" },
{ "iops_size", "throttling.iops-size" },
{ "group", "throttling.group" },
{ "readonly", BDRV_OPT_READ_ONLY },
};
for (i = 0; i < ARRAY_SIZE(opt_renames); i++) {
qemu_opt_rename(all_opts, opt_renames[i].from, opt_renames[i].to,
&local_err);
if (local_err) {
error_report_err(local_err);
return NULL;
}
}
value = qemu_opt_get(all_opts, "cache");
if (value) {
int flags = 0;
bool writethrough;
if (bdrv_parse_cache_mode(value, &flags, &writethrough) != 0) {
error_report("invalid cache option");
return NULL;
}
/* Specific options take precedence */
if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_WB)) {
qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_WB,
!writethrough, &error_abort);
}
if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_DIRECT)) {
qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_DIRECT,
!!(flags & BDRV_O_NOCACHE), &error_abort);
}
if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_NO_FLUSH)) {
qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_NO_FLUSH,
!!(flags & BDRV_O_NO_FLUSH), &error_abort);
}
qemu_opt_unset(all_opts, "cache");
}
/* Get a QDict for processing the options */
bs_opts = qdict_new();
qemu_opts_to_qdict(all_opts, bs_opts);
legacy_opts = qemu_opts_create(&qemu_legacy_drive_opts, NULL, 0,
&error_abort);
qemu_opts_absorb_qdict(legacy_opts, bs_opts, &local_err);
if (local_err) {
error_report_err(local_err);
goto fail;
}
/* Deprecated option boot=[on|off] */
if (qemu_opt_get(legacy_opts, "boot") != NULL) {
fprintf(stderr, "qemu-kvm: boot=on|off is deprecated and will be "
"ignored. Future versions will reject this parameter. Please "
"update your scripts.\n");
}
/* Media type */
value = qemu_opt_get(legacy_opts, "media");
if (value) {
if (!strcmp(value, "disk")) {
media = MEDIA_DISK;
} else if (!strcmp(value, "cdrom")) {
media = MEDIA_CDROM;
read_only = true;
} else {
error_report("'%s' invalid media", value);
goto fail;
}
}
/* copy-on-read is disabled with a warning for read-only devices */
read_only |= qemu_opt_get_bool(legacy_opts, BDRV_OPT_READ_ONLY, false);
copy_on_read = qemu_opt_get_bool(legacy_opts, "copy-on-read", false);
if (read_only && copy_on_read) {
error_report("warning: disabling copy-on-read on read-only drive");
copy_on_read = false;
}
qdict_put_str(bs_opts, BDRV_OPT_READ_ONLY, read_only ? "on" : "off");
qdict_put_str(bs_opts, "copy-on-read", copy_on_read ? "on" : "off");
/* Controller type */
value = qemu_opt_get(legacy_opts, "if");
if (value) {
for (type = 0;
type < IF_COUNT && strcmp(value, if_name[type]);
type++) {
}
if (type == IF_COUNT) {
error_report("unsupported bus type '%s'", value);
goto fail;
}
} else {
type = block_default_type;
}
/* Geometry */
cyls = qemu_opt_get_number(legacy_opts, "cyls", 0);
heads = qemu_opt_get_number(legacy_opts, "heads", 0);
secs = qemu_opt_get_number(legacy_opts, "secs", 0);
if (cyls || heads || secs) {
if (cyls < 1) {
error_report("invalid physical cyls number");
goto fail;
}
if (heads < 1) {
error_report("invalid physical heads number");
goto fail;
}
if (secs < 1) {
error_report("invalid physical secs number");
goto fail;
}
}
translation = BIOS_ATA_TRANSLATION_AUTO;
value = qemu_opt_get(legacy_opts, "trans");
if (value != NULL) {
if (!cyls) {
error_report("'%s' trans must be used with cyls, heads and secs",
value);
goto fail;
}
if (!strcmp(value, "none")) {
translation = BIOS_ATA_TRANSLATION_NONE;
} else if (!strcmp(value, "lba")) {
translation = BIOS_ATA_TRANSLATION_LBA;
} else if (!strcmp(value, "large")) {
translation = BIOS_ATA_TRANSLATION_LARGE;
} else if (!strcmp(value, "rechs")) {
translation = BIOS_ATA_TRANSLATION_RECHS;
} else if (!strcmp(value, "auto")) {
translation = BIOS_ATA_TRANSLATION_AUTO;
} else {
error_report("'%s' invalid translation type", value);
goto fail;
}
}
if (media == MEDIA_CDROM) {
if (cyls || secs || heads) {
error_report("CHS can't be set with media=cdrom");
goto fail;
}
}
/* Device address specified by bus/unit or index.
* If none was specified, try to find the first free one. */
bus_id = qemu_opt_get_number(legacy_opts, "bus", 0);
unit_id = qemu_opt_get_number(legacy_opts, "unit", -1);
index = qemu_opt_get_number(legacy_opts, "index", -1);
max_devs = if_max_devs[type];
if (index != -1) {
if (bus_id != 0 || unit_id != -1) {
error_report("index cannot be used with bus and unit");
goto fail;
}
bus_id = drive_index_to_bus_id(type, index);
unit_id = drive_index_to_unit_id(type, index);
}
if (unit_id == -1) {
unit_id = 0;
while (drive_get(type, bus_id, unit_id) != NULL) {
unit_id++;
if (max_devs && unit_id >= max_devs) {
unit_id -= max_devs;
bus_id++;
}
}
}
if (max_devs && unit_id >= max_devs) {
error_report("unit %d too big (max is %d)", unit_id, max_devs - 1);
goto fail;
}
if (drive_get(type, bus_id, unit_id) != NULL) {
error_report("drive with bus=%d, unit=%d (index=%d) exists",
bus_id, unit_id, index);
goto fail;
}
/* Serial number */
serial = qemu_opt_get(legacy_opts, "serial");
/* no id supplied -> create one */
if (qemu_opts_id(all_opts) == NULL) {
char *new_id;
const char *mediastr = "";
if (type == IF_IDE || type == IF_SCSI) {
mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
}
if (max_devs) {
new_id = g_strdup_printf("%s%i%s%i", if_name[type], bus_id,
mediastr, unit_id);
} else {
new_id = g_strdup_printf("%s%s%i", if_name[type],
mediastr, unit_id);
}
qdict_put_str(bs_opts, "id", new_id);
g_free(new_id);
}
/* Add virtio block device */
devaddr = qemu_opt_get(legacy_opts, "addr");
if (devaddr && type != IF_VIRTIO) {
error_report("addr is not supported by this bus type");
goto fail;
}
if (type == IF_VIRTIO) {
QemuOpts *devopts;
devopts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
&error_abort);
if (arch_type == QEMU_ARCH_S390X) {
qemu_opt_set(devopts, "driver", "virtio-blk-ccw", &error_abort);
} else {
qemu_opt_set(devopts, "driver", "virtio-blk-pci", &error_abort);
}
qemu_opt_set(devopts, "drive", qdict_get_str(bs_opts, "id"),
&error_abort);
if (devaddr) {
qemu_opt_set(devopts, "addr", devaddr, &error_abort);
}
}
filename = qemu_opt_get(legacy_opts, "file");
/* Check werror/rerror compatibility with if=... */
werror = qemu_opt_get(legacy_opts, "werror");
if (werror != NULL) {
if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO &&
type != IF_NONE) {
error_report("werror is not supported by this bus type");
goto fail;
}
qdict_put_str(bs_opts, "werror", werror);
}
rerror = qemu_opt_get(legacy_opts, "rerror");
if (rerror != NULL) {
if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI &&
type != IF_NONE) {
error_report("rerror is not supported by this bus type");
goto fail;
}
qdict_put_str(bs_opts, "rerror", rerror);
}
/* Actual block device init: Functionality shared with blockdev-add */
blk = blockdev_init(filename, bs_opts, &local_err);
bs_opts = NULL;
if (!blk) {
if (local_err) {
error_report_err(local_err);
}
goto fail;
} else {
assert(!local_err);
}
/* Create legacy DriveInfo */
dinfo = g_malloc0(sizeof(*dinfo));
dinfo->opts = all_opts;
dinfo->cyls = cyls;
dinfo->heads = heads;
dinfo->secs = secs;
dinfo->trans = translation;
dinfo->type = type;
dinfo->bus = bus_id;
dinfo->unit = unit_id;
dinfo->devaddr = devaddr;
dinfo->serial = g_strdup(serial);
blk_set_legacy_dinfo(blk, dinfo);
switch(type) {
case IF_IDE:
case IF_SCSI:
case IF_XEN:
case IF_NONE:
dinfo->media_cd = media == MEDIA_CDROM;
break;
default:
break;
}
fail:
qemu_opts_del(legacy_opts);
QDECREF(bs_opts);
return dinfo;
}
static BlockDriverState *qmp_get_root_bs(const char *name, Error **errp)
{
BlockDriverState *bs;
bs = bdrv_lookup_bs(name, name, errp);
if (bs == NULL) {
return NULL;
}
if (!bdrv_is_root_node(bs)) {
error_setg(errp, "Need a root block node");
return NULL;
}
if (!bdrv_is_inserted(bs)) {
error_setg(errp, "Device has no medium");
return NULL;
}
return bs;
}
static BlockBackend *qmp_get_blk(const char *blk_name, const char *qdev_id,
Error **errp)
{
BlockBackend *blk;
if (!blk_name == !qdev_id) {
error_setg(errp, "Need exactly one of 'device' and 'id'");
return NULL;
}
if (qdev_id) {
blk = blk_by_qdev_id(qdev_id, errp);
} else {
blk = blk_by_name(blk_name);
if (blk == NULL) {
error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
"Device '%s' not found", blk_name);
}
}
return blk;
}
void hmp_commit(Monitor *mon, const QDict *qdict)
{
const char *device = qdict_get_str(qdict, "device");
BlockBackend *blk;
int ret;
if (!strcmp(device, "all")) {
ret = blk_commit_all();
} else {
BlockDriverState *bs;
AioContext *aio_context;
blk = blk_by_name(device);
if (!blk) {
monitor_printf(mon, "Device '%s' not found\n", device);
return;
}
if (!blk_is_available(blk)) {
monitor_printf(mon, "Device '%s' has no medium\n", device);
return;
}
bs = blk_bs(blk);
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
ret = bdrv_commit(bs);
aio_context_release(aio_context);
}
if (ret < 0) {
monitor_printf(mon, "'commit' error for '%s': %s\n", device,
strerror(-ret));
}
}
static void blockdev_do_action(TransactionAction *action, Error **errp)
{
TransactionActionList list;
list.value = action;
list.next = NULL;
qmp_transaction(&list, false, NULL, errp);
}
void qmp_blockdev_snapshot_sync(bool has_device, const char *device,
bool has_node_name, const char *node_name,
const char *snapshot_file,
bool has_snapshot_node_name,
const char *snapshot_node_name,
bool has_format, const char *format,
bool has_mode, NewImageMode mode, Error **errp)
{
BlockdevSnapshotSync snapshot = {
.has_device = has_device,
.device = (char *) device,
.has_node_name = has_node_name,
.node_name = (char *) node_name,
.snapshot_file = (char *) snapshot_file,
.has_snapshot_node_name = has_snapshot_node_name,
.snapshot_node_name = (char *) snapshot_node_name,
.has_format = has_format,
.format = (char *) format,
.has_mode = has_mode,
.mode = mode,
};
TransactionAction action = {
.type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
.u.blockdev_snapshot_sync.data = &snapshot,
};
blockdev_do_action(&action, errp);
}
void qmp_blockdev_snapshot(const char *node, const char *overlay,
Error **errp)
{
BlockdevSnapshot snapshot_data = {
.node = (char *) node,
.overlay = (char *) overlay
};
TransactionAction action = {
.type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT,
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
.u.blockdev_snapshot.data = &snapshot_data,
};
blockdev_do_action(&action, errp);
}
void qmp_blockdev_snapshot_internal_sync(const char *device,
const char *name,
Error **errp)
{
BlockdevSnapshotInternal snapshot = {
.device = (char *) device,
.name = (char *) name
};
TransactionAction action = {
.type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC,
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
.u.blockdev_snapshot_internal_sync.data = &snapshot,
};
blockdev_do_action(&action, errp);
}
SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device,
bool has_id,
const char *id,
bool has_name,
const char *name,
Error **errp)
{
BlockDriverState *bs;
AioContext *aio_context;
QEMUSnapshotInfo sn;
Error *local_err = NULL;
SnapshotInfo *info = NULL;
int ret;
bs = qmp_get_root_bs(device, errp);
if (!bs) {
return NULL;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (!has_id) {
id = NULL;
}
if (!has_name) {
name = NULL;
}
if (!id && !name) {
error_setg(errp, "Name or id must be provided");
goto out_aio_context;
}
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, errp)) {
goto out_aio_context;
}
ret = bdrv_snapshot_find_by_id_and_name(bs, id, name, &sn, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out_aio_context;
}
if (!ret) {
error_setg(errp,
"Snapshot with id '%s' and name '%s' does not exist on "
"device '%s'",
STR_OR_NULL(id), STR_OR_NULL(name), device);
goto out_aio_context;
}
bdrv_snapshot_delete(bs, id, name, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out_aio_context;
}
aio_context_release(aio_context);
info = g_new0(SnapshotInfo, 1);
info->id = g_strdup(sn.id_str);
info->name = g_strdup(sn.name);
info->date_nsec = sn.date_nsec;
info->date_sec = sn.date_sec;
info->vm_state_size = sn.vm_state_size;
info->vm_clock_nsec = sn.vm_clock_nsec % 1000000000;
info->vm_clock_sec = sn.vm_clock_nsec / 1000000000;
return info;
out_aio_context:
aio_context_release(aio_context);
return NULL;
}
/**
* block_dirty_bitmap_lookup:
* Return a dirty bitmap (if present), after validating
* the node reference and bitmap names.
*
* @node: The name of the BDS node to search for bitmaps
* @name: The name of the bitmap to search for
* @pbs: Output pointer for BDS lookup, if desired. Can be NULL.
* @paio: Output pointer for aio_context acquisition, if desired. Can be NULL.
* @errp: Output pointer for error information. Can be NULL.
*
* @return: A bitmap object on success, or NULL on failure.
*/
static BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node,
const char *name,
BlockDriverState **pbs,
Error **errp)
{
BlockDriverState *bs;
BdrvDirtyBitmap *bitmap;
if (!node) {
error_setg(errp, "Node cannot be NULL");
return NULL;
}
if (!name) {
error_setg(errp, "Bitmap name cannot be NULL");
return NULL;
}
bs = bdrv_lookup_bs(node, node, NULL);
if (!bs) {
error_setg(errp, "Node '%s' not found", node);
return NULL;
}
bitmap = bdrv_find_dirty_bitmap(bs, name);
if (!bitmap) {
error_setg(errp, "Dirty bitmap '%s' not found", name);
return NULL;
}
if (pbs) {
*pbs = bs;
}
return bitmap;
}
/* New and old BlockDriverState structs for atomic group operations */
typedef struct BlkActionState BlkActionState;
/**
* BlkActionOps:
* Table of operations that define an Action.
*
* @instance_size: Size of state struct, in bytes.
* @prepare: Prepare the work, must NOT be NULL.
* @commit: Commit the changes, can be NULL.
* @abort: Abort the changes on fail, can be NULL.
* @clean: Clean up resources after all transaction actions have called
* commit() or abort(). Can be NULL.
*
* Only prepare() may fail. In a single transaction, only one of commit() or
* abort() will be called. clean() will always be called if it is present.
*/
typedef struct BlkActionOps {
size_t instance_size;
void (*prepare)(BlkActionState *common, Error **errp);
void (*commit)(BlkActionState *common);
void (*abort)(BlkActionState *common);
void (*clean)(BlkActionState *common);
} BlkActionOps;
/**
* BlkActionState:
* Describes one Action's state within a Transaction.
*
* @action: QAPI-defined enum identifying which Action to perform.
* @ops: Table of ActionOps this Action can perform.
* @block_job_txn: Transaction which this action belongs to.
* @entry: List membership for all Actions in this Transaction.
*
* This structure must be arranged as first member in a subclassed type,
* assuming that the compiler will also arrange it to the same offsets as the
* base class.
*/
struct BlkActionState {
TransactionAction *action;
const BlkActionOps *ops;
BlockJobTxn *block_job_txn;
TransactionProperties *txn_props;
QSIMPLEQ_ENTRY(BlkActionState) entry;
};
/* internal snapshot private data */
typedef struct InternalSnapshotState {
BlkActionState common;
BlockDriverState *bs;
AioContext *aio_context;
QEMUSnapshotInfo sn;
bool created;
} InternalSnapshotState;
static int action_check_completion_mode(BlkActionState *s, Error **errp)
{
if (s->txn_props->completion_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
error_setg(errp,
"Action '%s' does not support Transaction property "
"completion-mode = %s",
TransactionActionKind_lookup[s->action->type],
ActionCompletionMode_lookup[s->txn_props->completion_mode]);
return -1;
}
return 0;
}
static void internal_snapshot_prepare(BlkActionState *common,
Error **errp)
{
Error *local_err = NULL;
const char *device;
const char *name;
BlockDriverState *bs;
QEMUSnapshotInfo old_sn, *sn;
bool ret;
qemu_timeval tv;
BlockdevSnapshotInternal *internal;
InternalSnapshotState *state;
int ret1;
g_assert(common->action->type ==
TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC);
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
internal = common->action->u.blockdev_snapshot_internal_sync.data;
state = DO_UPCAST(InternalSnapshotState, common, common);
/* 1. parse input */
device = internal->device;
name = internal->name;
/* 2. check for validation */
if (action_check_completion_mode(common, errp) < 0) {
return;
}
bs = qmp_get_root_bs(device, errp);
if (!bs) {
return;
}
/* AioContext is released in .clean() */
state->aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(state->aio_context);
state->bs = bs;
bdrv_drained_begin(bs);
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, errp)) {
return;
}
if (bdrv_is_read_only(bs)) {
error_setg(errp, "Device '%s' is read only", device);
return;
}
if (!bdrv_can_snapshot(bs)) {
error_setg(errp, "Block format '%s' used by device '%s' "
"does not support internal snapshots",
bs->drv->format_name, device);
return;
}
if (!strlen(name)) {
error_setg(errp, "Name is empty");
return;
}
/* check whether a snapshot with name exist */
ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn,
&local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
} else if (ret) {
error_setg(errp,
"Snapshot with name '%s' already exists on device '%s'",
name, device);
return;
}
/* 3. take the snapshot */
sn = &state->sn;
pstrcpy(sn->name, sizeof(sn->name), name);
qemu_gettimeofday(&tv);
sn->date_sec = tv.tv_sec;
sn->date_nsec = tv.tv_usec * 1000;
sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
ret1 = bdrv_snapshot_create(bs, sn);
if (ret1 < 0) {
error_setg_errno(errp, -ret1,
"Failed to create snapshot '%s' on device '%s'",
name, device);
return;
}
/* 4. succeed, mark a snapshot is created */
state->created = true;
}
static void internal_snapshot_abort(BlkActionState *common)
{
InternalSnapshotState *state =
DO_UPCAST(InternalSnapshotState, common, common);
BlockDriverState *bs = state->bs;
QEMUSnapshotInfo *sn = &state->sn;
Error *local_error = NULL;
if (!state->created) {
return;
}
if (bdrv_snapshot_delete(bs, sn->id_str, sn->name, &local_error) < 0) {
error_reportf_err(local_error,
"Failed to delete snapshot with id '%s' and "
"name '%s' on device '%s' in abort: ",
sn->id_str, sn->name,
bdrv_get_device_name(bs));
}
}
static void internal_snapshot_clean(BlkActionState *common)
{
InternalSnapshotState *state = DO_UPCAST(InternalSnapshotState,
common, common);
if (state->aio_context) {
if (state->bs) {
bdrv_drained_end(state->bs);
}
aio_context_release(state->aio_context);
}
}
/* external snapshot private data */
typedef struct ExternalSnapshotState {
BlkActionState common;
BlockDriverState *old_bs;
BlockDriverState *new_bs;
AioContext *aio_context;
bool overlay_appended;
} ExternalSnapshotState;
static void external_snapshot_prepare(BlkActionState *common,
Error **errp)
{
int flags = 0;
QDict *options = NULL;
Error *local_err = NULL;
/* Device and node name of the image to generate the snapshot from */
const char *device;
const char *node_name;
/* Reference to the new image (for 'blockdev-snapshot') */
const char *snapshot_ref;
/* File name of the new image (for 'blockdev-snapshot-sync') */
const char *new_image_file;
ExternalSnapshotState *state =
DO_UPCAST(ExternalSnapshotState, common, common);
TransactionAction *action = common->action;
/* 'blockdev-snapshot' and 'blockdev-snapshot-sync' have similar
* purpose but a different set of parameters */
switch (action->type) {
case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
{
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
BlockdevSnapshot *s = action->u.blockdev_snapshot.data;
device = s->node;
node_name = s->node;
new_image_file = NULL;
snapshot_ref = s->overlay;
}
break;
case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
{
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
device = s->has_device ? s->device : NULL;
node_name = s->has_node_name ? s->node_name : NULL;
new_image_file = s->snapshot_file;
snapshot_ref = NULL;
}
break;
default:
g_assert_not_reached();
}
/* start processing */
if (action_check_completion_mode(common, errp) < 0) {
return;
}
state->old_bs = bdrv_lookup_bs(device, node_name, errp);
if (!state->old_bs) {
return;
}
/* Acquire AioContext now so any threads operating on old_bs stop */
state->aio_context = bdrv_get_aio_context(state->old_bs);
aio_context_acquire(state->aio_context);
bdrv_drained_begin(state->old_bs);
if (!bdrv_is_inserted(state->old_bs)) {
error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
return;
}
if (bdrv_op_is_blocked(state->old_bs,
BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
return;
}
if (!bdrv_is_read_only(state->old_bs)) {
if (bdrv_flush(state->old_bs)) {
error_setg(errp, QERR_IO_ERROR);
return;
}
}
if (!bdrv_is_first_non_filter(state->old_bs)) {
error_setg(errp, QERR_FEATURE_DISABLED, "snapshot");
return;
}
if (action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC) {
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
const char *format = s->has_format ? s->format : "qcow2";
enum NewImageMode mode;
const char *snapshot_node_name =
s->has_snapshot_node_name ? s->snapshot_node_name : NULL;
if (node_name && !snapshot_node_name) {
error_setg(errp, "New snapshot node name missing");
return;
}
if (snapshot_node_name &&
bdrv_lookup_bs(snapshot_node_name, snapshot_node_name, NULL)) {
error_setg(errp, "New snapshot node name already in use");
return;
}
flags = state->old_bs->open_flags;
block: Remove copy-on-read from bdrv_move_feature_fields() Ever since we first introduced bdrv_append() in commit 8802d1fd ('qapi: Introduce blockdev-group-snapshot-sync command'), the copy-on-read flag was moved to the new top layer when taking a snapshot. The only problem is that it doesn't make a whole lot of sense. The use case for manually enabled CoR is to avoid reading data twice from a slow remote image, so we want to save it to a local overlay, say an ISO image accessed via HTTP to a local qcow2 overlay. When taking a snapshot, we end up with a backing chain like this: http <- local.qcow2 <- snap_overlay.qcow2 There is no point in doing CoR from local.qcow2 into snap_overlay.qcow2, we just want to keep copying data from the remote source into local.qcow2. The other use case of CoR is in the context of streaming, which isn't very interesting for bdrv_move_feature_fields() because op blockers prevent this combination. This patch makes the copy-on-read flag stay on the image for which it was originally set and prevents it from being propagated to the new overlay. It is no longer intended to move CoR to the BlockBackend level. In order for this to make sense, we also need to keep the respective image read-write. As a side effect of these changes, creating a live snapshot image (as opposed to using an existing externally created one) on top of a COR block device works now. It used to fail because it tried to open its backing file both read-only and with COR. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-29 13:12:26 +01:00
flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ);
/* create new image w/backing file */
mode = s->has_mode ? s->mode : NEW_IMAGE_MODE_ABSOLUTE_PATHS;
if (mode != NEW_IMAGE_MODE_EXISTING) {
int64_t size = bdrv_getlength(state->old_bs);
if (size < 0) {
error_setg_errno(errp, -size, "bdrv_getlength failed");
return;
}
bdrv_img_create(new_image_file, format,
state->old_bs->filename,
state->old_bs->drv->format_name,
NULL, size, flags, false, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
options = qdict_new();
if (s->has_snapshot_node_name) {
qdict_put_str(options, "node-name", snapshot_node_name);
}
qdict_put_str(options, "driver", format);
flags |= BDRV_O_NO_BACKING;
}
state->new_bs = bdrv_open(new_image_file, snapshot_ref, options, flags,
errp);
/* We will manually add the backing_hd field to the bs later */
if (!state->new_bs) {
return;
}
if (bdrv_has_blk(state->new_bs)) {
error_setg(errp, "The snapshot is already in use");
return;
}
if (bdrv_op_is_blocked(state->new_bs, BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
errp)) {
return;
}
if (state->new_bs->backing != NULL) {
error_setg(errp, "The snapshot already has a backing image");
return;
}
if (!state->new_bs->drv->supports_backing) {
error_setg(errp, "The snapshot does not support backing images");
return;
}
bdrv_set_aio_context(state->new_bs, state->aio_context);
/* This removes our old bs and adds the new bs. This is an operation that
* can fail, so we need to do it in .prepare; undoing it for abort is
* always possible. */
bdrv_ref(state->new_bs);
bdrv_append(state->new_bs, state->old_bs, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
state->overlay_appended = true;
}
static void external_snapshot_commit(BlkActionState *common)
{
ExternalSnapshotState *state =
DO_UPCAST(ExternalSnapshotState, common, common);
/* We don't need (or want) to use the transactional
* bdrv_reopen_multiple() across all the entries at once, because we
* don't want to abort all of them if one of them fails the reopen */
if (!atomic_read(&state->old_bs->copy_on_read)) {
block: Remove copy-on-read from bdrv_move_feature_fields() Ever since we first introduced bdrv_append() in commit 8802d1fd ('qapi: Introduce blockdev-group-snapshot-sync command'), the copy-on-read flag was moved to the new top layer when taking a snapshot. The only problem is that it doesn't make a whole lot of sense. The use case for manually enabled CoR is to avoid reading data twice from a slow remote image, so we want to save it to a local overlay, say an ISO image accessed via HTTP to a local qcow2 overlay. When taking a snapshot, we end up with a backing chain like this: http <- local.qcow2 <- snap_overlay.qcow2 There is no point in doing CoR from local.qcow2 into snap_overlay.qcow2, we just want to keep copying data from the remote source into local.qcow2. The other use case of CoR is in the context of streaming, which isn't very interesting for bdrv_move_feature_fields() because op blockers prevent this combination. This patch makes the copy-on-read flag stay on the image for which it was originally set and prevents it from being propagated to the new overlay. It is no longer intended to move CoR to the BlockBackend level. In order for this to make sense, we also need to keep the respective image read-write. As a side effect of these changes, creating a live snapshot image (as opposed to using an existing externally created one) on top of a COR block device works now. It used to fail because it tried to open its backing file both read-only and with COR. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-29 13:12:26 +01:00
bdrv_reopen(state->old_bs, state->old_bs->open_flags & ~BDRV_O_RDWR,
NULL);
}
}
static void external_snapshot_abort(BlkActionState *common)
{
ExternalSnapshotState *state =
DO_UPCAST(ExternalSnapshotState, common, common);
if (state->new_bs) {
if (state->overlay_appended) {
bdrv_ref(state->old_bs); /* we can't let bdrv_set_backind_hd()
close state->old_bs; we need it */
bdrv_set_backing_hd(state->new_bs, NULL, &error_abort);
bdrv_replace_node(state->new_bs, state->old_bs, &error_abort);
bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */
}
}
}
static void external_snapshot_clean(BlkActionState *common)
{
ExternalSnapshotState *state =
DO_UPCAST(ExternalSnapshotState, common, common);
if (state->aio_context) {
bdrv_drained_end(state->old_bs);
aio_context_release(state->aio_context);
bdrv_unref(state->new_bs);
}
}
typedef struct DriveBackupState {
BlkActionState common;
BlockDriverState *bs;
AioContext *aio_context;
BlockJob *job;
} DriveBackupState;
static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,
Error **errp);
static void drive_backup_prepare(BlkActionState *common, Error **errp)
{
DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
BlockDriverState *bs;
DriveBackup *backup;
Error *local_err = NULL;
assert(common->action->type == TRANSACTION_ACTION_KIND_DRIVE_BACKUP);
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
backup = common->action->u.drive_backup.data;
bs = qmp_get_root_bs(backup->device, errp);
if (!bs) {
return;
}
/* AioContext is released in .clean() */
state->aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(state->aio_context);
bdrv_drained_begin(bs);
state->bs = bs;
state->job = do_drive_backup(backup, common->block_job_txn, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
static void drive_backup_commit(BlkActionState *common)
{
DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
assert(state->job);
block_job_start(state->job);
}
static void drive_backup_abort(BlkActionState *common)
{
DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
if (state->job) {
block_job_cancel_sync(state->job);
}
}
static void drive_backup_clean(BlkActionState *common)
{
DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
if (state->aio_context) {
bdrv_drained_end(state->bs);
aio_context_release(state->aio_context);
}
}
typedef struct BlockdevBackupState {
BlkActionState common;
BlockDriverState *bs;
BlockJob *job;
AioContext *aio_context;
} BlockdevBackupState;
static BlockJob *do_blockdev_backup(BlockdevBackup *backup, BlockJobTxn *txn,
Error **errp);
static void blockdev_backup_prepare(BlkActionState *common, Error **errp)
{
BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
BlockdevBackup *backup;
BlockDriverState *bs, *target;
Error *local_err = NULL;
assert(common->action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP);
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
backup = common->action->u.blockdev_backup.data;
bs = qmp_get_root_bs(backup->device, errp);
if (!bs) {
return;
}
target = bdrv_lookup_bs(backup->target, backup->target, errp);
if (!target) {
return;
}
/* AioContext is released in .clean() */
state->aio_context = bdrv_get_aio_context(bs);
if (state->aio_context != bdrv_get_aio_context(target)) {
state->aio_context = NULL;
error_setg(errp, "Backup between two IO threads is not implemented");
return;
}
aio_context_acquire(state->aio_context);
state->bs = bs;
bdrv_drained_begin(state->bs);
state->job = do_blockdev_backup(backup, common->block_job_txn, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
static void blockdev_backup_commit(BlkActionState *common)
{
BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
assert(state->job);
block_job_start(state->job);
}
static void blockdev_backup_abort(BlkActionState *common)
{
BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
if (state->job) {
block_job_cancel_sync(state->job);
}
}
static void blockdev_backup_clean(BlkActionState *common)
{
BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
if (state->aio_context) {
bdrv_drained_end(state->bs);
aio_context_release(state->aio_context);
}
}
typedef struct BlockDirtyBitmapState {
BlkActionState common;
BdrvDirtyBitmap *bitmap;
BlockDriverState *bs;
AioContext *aio_context;
HBitmap *backup;
bool prepared;
} BlockDirtyBitmapState;
static void block_dirty_bitmap_add_prepare(BlkActionState *common,
Error **errp)
{
Error *local_err = NULL;
BlockDirtyBitmapAdd *action;
BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
common, common);
if (action_check_completion_mode(common, errp) < 0) {
return;
}
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
action = common->action->u.block_dirty_bitmap_add.data;
/* AIO context taken and released within qmp_block_dirty_bitmap_add */
qmp_block_dirty_bitmap_add(action->node, action->name,
action->has_granularity, action->granularity,
&local_err);
if (!local_err) {
state->prepared = true;
} else {
error_propagate(errp, local_err);
}
}
static void block_dirty_bitmap_add_abort(BlkActionState *common)
{
BlockDirtyBitmapAdd *action;
BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
common, common);
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
action = common->action->u.block_dirty_bitmap_add.data;
/* Should not be able to fail: IF the bitmap was added via .prepare(),
* then the node reference and bitmap name must have been valid.
*/
if (state->prepared) {
qmp_block_dirty_bitmap_remove(action->node, action->name, &error_abort);
}
}
static void block_dirty_bitmap_clear_prepare(BlkActionState *common,
Error **errp)
{
BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
common, common);
BlockDirtyBitmap *action;
if (action_check_completion_mode(common, errp) < 0) {
return;
}
qapi: Don't special-case simple union wrappers Simple unions were carrying a special case that hid their 'data' QMP member from the resulting C struct, via the hack method QAPISchemaObjectTypeVariant.simple_union_type(). But by using the work we started by unboxing flat union and alternate branches, coupled with the ability to visit the members of an implicit type, we can now expose the simple union's implicit type in qapi-types.h: | struct q_obj_ImageInfoSpecificQCow2_wrapper { | ImageInfoSpecificQCow2 *data; | }; | | struct q_obj_ImageInfoSpecificVmdk_wrapper { | ImageInfoSpecificVmdk *data; | }; ... | struct ImageInfoSpecific { | ImageInfoSpecificKind type; | union { /* union tag is @type */ | void *data; |- ImageInfoSpecificQCow2 *qcow2; |- ImageInfoSpecificVmdk *vmdk; |+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2; |+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk; | } u; | }; Doing this removes asymmetry between QAPI's QMP side and its C side (both sides now expose 'data'), and means that the treatment of a simple union as sugar for a flat union is now equivalent in both languages (previously the two approaches used a different layer of dereferencing, where the simple union could be converted to a flat union with equivalent C layout but different {} on the wire, or to an equivalent QMP wire form but with different C representation). Using the implicit type also lets us get rid of the simple_union_type() hack. Of course, now all clients of simple unions have to adjust from using su->u.member to using su->u.member.data; while this touches a number of files in the tree, some earlier cleanup patches helped minimize the change to the initialization of a temporary variable rather than every single member access. The generated qapi-visit.c code is also affected by the layout change: |@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member | } | switch (obj->type) { | case IMAGE_INFO_SPECIFIC_KIND_QCOW2: |- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err); |+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err); | break; | case IMAGE_INFO_SPECIFIC_KIND_VMDK: |- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err); |+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err); | break; | default: | abort(); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-17 23:48:37 +01:00
action = common->action->u.block_dirty_bitmap_clear.data;
state->bitmap = block_dirty_bitmap_lookup(action->node,
action->name,
&state->bs,
errp);
if (!state->bitmap) {
return;
}
if (bdrv_dirty_bitmap_frozen(state->bitmap)) {
error_setg(errp, "Cannot modify a frozen bitmap");
return;
} else if (!bdrv_dirty_bitmap_enabled(state->bitmap)) {
error_setg(errp, "Cannot clear a disabled bitmap");
return;
}
bdrv_clear_dirty_bitmap(state->bitmap, &state->backup);
/* AioContext is released in .clean() */
}
static void block_dirty_bitmap_clear_abort(BlkActionState *common)
{
BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
common, common);
if (state->backup) {
bdrv_undo_clear_dirty_bitmap(state->bitmap, state->backup);
}
}
static void block_dirty_bitmap_clear_commit(BlkActionState *common)
{
BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
common, common);
hbitmap_free(state->backup);
}
static void block_dirty_bitmap_clear_clean(BlkActionState *common)
{
BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
common, common);
if (state->aio_context) {
aio_context_release(state->aio_context);
}
}
static void abort_prepare(BlkActionState *common, Error **errp)
{
error_setg(errp, "Transaction aborted using Abort action");
}
static void abort_commit(BlkActionState *common)
{
g_assert_not_reached(); /* this action never succeeds */
}
static const BlkActionOps actions[] = {
[TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT] = {
.instance_size = sizeof(ExternalSnapshotState),
.prepare = external_snapshot_prepare,
.commit = external_snapshot_commit,
.abort = external_snapshot_abort,
.clean = external_snapshot_clean,
},
[TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC] = {
.instance_size = sizeof(ExternalSnapshotState),
.prepare = external_snapshot_prepare,
.commit = external_snapshot_commit,
.abort = external_snapshot_abort,
.clean = external_snapshot_clean,
},
[TRANSACTION_ACTION_KIND_DRIVE_BACKUP] = {
.instance_size = sizeof(DriveBackupState),
.prepare = drive_backup_prepare,
.commit = drive_backup_commit,
.abort = drive_backup_abort,
.clean = drive_backup_clean,
},
[TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP] = {
.instance_size = sizeof(BlockdevBackupState),
.prepare = blockdev_backup_prepare,
.commit = blockdev_backup_commit,
.abort = blockdev_backup_abort,
.clean = blockdev_backup_clean,
},
[TRANSACTION_ACTION_KIND_ABORT] = {
.instance_size = sizeof(BlkActionState),
.prepare = abort_prepare,
.commit = abort_commit,
},
[TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC] = {
.instance_size = sizeof(InternalSnapshotState),
.prepare = internal_snapshot_prepare,
.abort = internal_snapshot_abort,
.clean = internal_snapshot_clean,
},
[TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD] = {
.instance_size = sizeof(BlockDirtyBitmapState),
.prepare = block_dirty_bitmap_add_prepare,
.abort = block_dirty_bitmap_add_abort,
},
[TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR] = {
.instance_size = sizeof(BlockDirtyBitmapState),
.prepare = block_dirty_bitmap_clear_prepare,
.commit = block_dirty_bitmap_clear_commit,
.abort = block_dirty_bitmap_clear_abort,
.clean = block_dirty_bitmap_clear_clean,
}
};
/**
* Allocate a TransactionProperties structure if necessary, and fill
* that structure with desired defaults if they are unset.
*/
static TransactionProperties *get_transaction_properties(
TransactionProperties *props)
{
if (!props) {
props = g_new0(TransactionProperties, 1);
}
if (!props->has_completion_mode) {
props->has_completion_mode = true;
props->completion_mode = ACTION_COMPLETION_MODE_INDIVIDUAL;
}
return props;
}
/*
* 'Atomic' group operations. The operations are performed as a set, and if
* any fail then we roll back all operations in the group.
*/
void qmp_transaction(TransactionActionList *dev_list,
bool has_props,
struct TransactionProperties *props,
Error **errp)
{
TransactionActionList *dev_entry = dev_list;
BlockJobTxn *block_job_txn = NULL;
BlkActionState *state, *next;
Error *local_err = NULL;
QSIMPLEQ_HEAD(snap_bdrv_states, BlkActionState) snap_bdrv_states;
QSIMPLEQ_INIT(&snap_bdrv_states);
/* Does this transaction get canceled as a group on failure?
* If not, we don't really need to make a BlockJobTxn.
*/
props = get_transaction_properties(props);
if (props->completion_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
block_job_txn = block_job_txn_new();
}
/* drain all i/o before any operations */
bdrv_drain_all();
/* We don't do anything in this loop that commits us to the operations */
while (NULL != dev_entry) {
TransactionAction *dev_info = NULL;
const BlkActionOps *ops;
dev_info = dev_entry->value;
dev_entry = dev_entry->next;
assert(dev_info->type < ARRAY_SIZE(actions));
ops = &actions[dev_info->type];
assert(ops->instance_size > 0);
state = g_malloc0(ops->instance_size);
state->ops = ops;
state->action = dev_info;
state->block_job_txn = block_job_txn;
state->txn_props = props;
QSIMPLEQ_INSERT_TAIL(&snap_bdrv_states, state, entry);
state->ops->prepare(state, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto delete_and_fail;
}
}
QSIMPLEQ_FOREACH(state, &snap_bdrv_states, entry) {
if (state->ops->commit) {
state->ops->commit(state);
}
}
/* success */
goto exit;
delete_and_fail:
/* failure, and it is all-or-none; roll back all operations */
QSIMPLEQ_FOREACH(state, &snap_bdrv_states, entry) {
if (state->ops->abort) {
state->ops->abort(state);
}
}
exit:
QSIMPLEQ_FOREACH_SAFE(state, &snap_bdrv_states, entry, next) {
if (state->ops->clean) {
state->ops->clean(state);
}
g_free(state);
}
if (!has_props) {
qapi_free_TransactionProperties(props);
}
block_job_txn_unref(block_job_txn);
}
void qmp_eject(bool has_device, const char *device,
bool has_id, const char *id,
bool has_force, bool force, Error **errp)
{
Error *local_err = NULL;
int rc;
if (!has_force) {
force = false;
}
rc = do_open_tray(has_device ? device : NULL,
has_id ? id : NULL,
force, &local_err);
if (rc && rc != -ENOSYS) {
error_propagate(errp, local_err);
return;
}
error_free(local_err);
qmp_x_blockdev_remove_medium(has_device, device, has_id, id, errp);
}
qmp: Allow to change password on named block driver states. Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> There was two candidate ways to implement named node manipulation: 1) { 'command': 'block_passwd', 'data': {'*device': 'str', '*node-name': 'str', 'password': 'str'} } 2) { 'command': 'block_passwd', 'data': {'device': 'str', '*device-is-node': 'bool', 'password': 'str'} } Luiz proposed 1 and says 2 was an abuse of the QMP interface and proposed to rewrite the QMP block interface for 2.0. Luiz does not like in 1 the fact that 2 fields are optional but one of them must be specified leading to an abuse of the QMP semantic. Kevin argumented that 2 what a clear abuse of the device field and would not be practical when reading fast some log file because the user would read "device" and think that a device is manipulated when it's in fact a node name. Documentation of 1 make it pretty clear what to do for the user. Kevin argued that all bs are node including devices ones so 2 does not make sense. Kevin also argued that rewriting the QMP block interface would not make disapear the current one. Kevin pushed the argument that making the QAPI generator compatible with the semantic of the operation would need a rewrite that no one has done yet. A vote has been done on the list to elect the version to use and 1 won. For reference the complete thread is: "[Qemu-devel] [PATCH V4 4/7] qmp: Allow to change password on names block driver states." Signed-off-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-23 21:31:35 +01:00
void qmp_block_passwd(bool has_device, const char *device,
bool has_node_name, const char *node_name,
const char *password, Error **errp)
{
qmp: Allow to change password on named block driver states. Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> There was two candidate ways to implement named node manipulation: 1) { 'command': 'block_passwd', 'data': {'*device': 'str', '*node-name': 'str', 'password': 'str'} } 2) { 'command': 'block_passwd', 'data': {'device': 'str', '*device-is-node': 'bool', 'password': 'str'} } Luiz proposed 1 and says 2 was an abuse of the QMP interface and proposed to rewrite the QMP block interface for 2.0. Luiz does not like in 1 the fact that 2 fields are optional but one of them must be specified leading to an abuse of the QMP semantic. Kevin argumented that 2 what a clear abuse of the device field and would not be practical when reading fast some log file because the user would read "device" and think that a device is manipulated when it's in fact a node name. Documentation of 1 make it pretty clear what to do for the user. Kevin argued that all bs are node including devices ones so 2 does not make sense. Kevin also argued that rewriting the QMP block interface would not make disapear the current one. Kevin pushed the argument that making the QAPI generator compatible with the semantic of the operation would need a rewrite that no one has done yet. A vote has been done on the list to elect the version to use and 1 won. For reference the complete thread is: "[Qemu-devel] [PATCH V4 4/7] qmp: Allow to change password on names block driver states." Signed-off-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-23 21:31:35 +01:00
Error *local_err = NULL;
BlockDriverState *bs;
AioContext *aio_context;
qmp: Allow to change password on named block driver states. Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> There was two candidate ways to implement named node manipulation: 1) { 'command': 'block_passwd', 'data': {'*device': 'str', '*node-name': 'str', 'password': 'str'} } 2) { 'command': 'block_passwd', 'data': {'device': 'str', '*device-is-node': 'bool', 'password': 'str'} } Luiz proposed 1 and says 2 was an abuse of the QMP interface and proposed to rewrite the QMP block interface for 2.0. Luiz does not like in 1 the fact that 2 fields are optional but one of them must be specified leading to an abuse of the QMP semantic. Kevin argumented that 2 what a clear abuse of the device field and would not be practical when reading fast some log file because the user would read "device" and think that a device is manipulated when it's in fact a node name. Documentation of 1 make it pretty clear what to do for the user. Kevin argued that all bs are node including devices ones so 2 does not make sense. Kevin also argued that rewriting the QMP block interface would not make disapear the current one. Kevin pushed the argument that making the QAPI generator compatible with the semantic of the operation would need a rewrite that no one has done yet. A vote has been done on the list to elect the version to use and 1 won. For reference the complete thread is: "[Qemu-devel] [PATCH V4 4/7] qmp: Allow to change password on names block driver states." Signed-off-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-23 21:31:35 +01:00
bs = bdrv_lookup_bs(has_device ? device : NULL,
has_node_name ? node_name : NULL,
&local_err);
if (local_err) {
qmp: Allow to change password on named block driver states. Signed-off-by: Benoit Canet <benoit@irqsave.net> Reviewed-by: Fam Zheng <famz@redhat.com> There was two candidate ways to implement named node manipulation: 1) { 'command': 'block_passwd', 'data': {'*device': 'str', '*node-name': 'str', 'password': 'str'} } 2) { 'command': 'block_passwd', 'data': {'device': 'str', '*device-is-node': 'bool', 'password': 'str'} } Luiz proposed 1 and says 2 was an abuse of the QMP interface and proposed to rewrite the QMP block interface for 2.0. Luiz does not like in 1 the fact that 2 fields are optional but one of them must be specified leading to an abuse of the QMP semantic. Kevin argumented that 2 what a clear abuse of the device field and would not be practical when reading fast some log file because the user would read "device" and think that a device is manipulated when it's in fact a node name. Documentation of 1 make it pretty clear what to do for the user. Kevin argued that all bs are node including devices ones so 2 does not make sense. Kevin also argued that rewriting the QMP block interface would not make disapear the current one. Kevin pushed the argument that making the QAPI generator compatible with the semantic of the operation would need a rewrite that no one has done yet. A vote has been done on the list to elect the version to use and 1 won. For reference the complete thread is: "[Qemu-devel] [PATCH V4 4/7] qmp: Allow to change password on names block driver states." Signed-off-by: Benoit Canet <benoit@irqsave.net> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-23 21:31:35 +01:00
error_propagate(errp, local_err);
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
bdrv_add_key(bs, password, errp);
aio_context_release(aio_context);
}
/*
* Attempt to open the tray of @device.
* If @force, ignore its tray lock.
* Else, if the tray is locked, don't open it, but ask the guest to open it.
* On error, store an error through @errp and return -errno.
* If @device does not exist, return -ENODEV.
* If it has no removable media, return -ENOTSUP.
* If it has no tray, return -ENOSYS.
* If the guest was asked to open the tray, return -EINPROGRESS.
* Else, return 0.
*/
static int do_open_tray(const char *blk_name, const char *qdev_id,
bool force, Error **errp)
{
BlockBackend *blk;
const char *device = qdev_id ?: blk_name;
bool locked;
blk = qmp_get_blk(blk_name, qdev_id, errp);
if (!blk) {
return -ENODEV;
}
if (!blk_dev_has_removable_media(blk)) {
error_setg(errp, "Device '%s' is not removable", device);
return -ENOTSUP;
}
if (!blk_dev_has_tray(blk)) {
error_setg(errp, "Device '%s' does not have a tray", device);
return -ENOSYS;
}
if (blk_dev_is_tray_open(blk)) {
return 0;
}
locked = blk_dev_is_medium_locked(blk);
if (locked) {
blk_dev_eject_request(blk, force);
}
if (!locked || force) {
blk_dev_change_media_cb(blk, false, &error_abort);
}
if (locked && !force) {
error_setg(errp, "Device '%s' is locked and force was not specified, "
"wait for tray to open and try again", device);
return -EINPROGRESS;
}
return 0;
}
void qmp_blockdev_open_tray(bool has_device, const char *device,
bool has_id, const char *id,
bool has_force, bool force,
Error **errp)
{
Error *local_err = NULL;
int rc;
if (!has_force) {
force = false;
}
rc = do_open_tray(has_device ? device : NULL,
has_id ? id : NULL,
force, &local_err);
if (rc && rc != -ENOSYS && rc != -EINPROGRESS) {
error_propagate(errp, local_err);
return;
}
error_free(local_err);
}
void qmp_blockdev_close_tray(bool has_device, const char *device,
bool has_id, const char *id,
Error **errp)
{
BlockBackend *blk;
Error *local_err = NULL;
device = has_device ? device : NULL;
id = has_id ? id : NULL;
blk = qmp_get_blk(device, id, errp);
if (!blk) {
return;
}
if (!blk_dev_has_removable_media(blk)) {
error_setg(errp, "Device '%s' is not removable", device ?: id);
return;
}
if (!blk_dev_has_tray(blk)) {
/* Ignore this command on tray-less devices */
return;
}
if (!blk_dev_is_tray_open(blk)) {
return;
}
blk_dev_change_media_cb(blk, true, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
}
void qmp_x_blockdev_remove_medium(bool has_device, const char *device,
bool has_id, const char *id, Error **errp)
{
BlockBackend *blk;
BlockDriverState *bs;
AioContext *aio_context;
bool has_attached_device;
device = has_device ? device : NULL;
id = has_id ? id : NULL;
blk = qmp_get_blk(device, id, errp);
if (!blk) {
return;
}
/* For BBs without a device, we can exchange the BDS tree at will */
has_attached_device = blk_get_attached_dev(blk);
if (has_attached_device && !blk_dev_has_removable_media(blk)) {
error_setg(errp, "Device '%s' is not removable", device ?: id);
return;
}
if (has_attached_device && blk_dev_has_tray(blk) &&
!blk_dev_is_tray_open(blk))
{
error_setg(errp, "Tray of device '%s' is not open", device ?: id);
return;
}
bs = blk_bs(blk);
if (!bs) {
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
goto out;
}
blk_remove_bs(blk);
if (!blk_dev_has_tray(blk)) {
/* For tray-less devices, blockdev-open-tray is a no-op (or may not be
* called at all); therefore, the medium needs to be ejected here.
* Do it after blk_remove_bs() so blk_is_inserted(blk) returns the @load
* value passed here (i.e. false). */
blk_dev_change_media_cb(blk, false, &error_abort);
}
out:
aio_context_release(aio_context);
}
static void qmp_blockdev_insert_anon_medium(BlockBackend *blk,
BlockDriverState *bs, Error **errp)
{
Error *local_err = NULL;
bool has_device;
int ret;
/* For BBs without a device, we can exchange the BDS tree at will */
has_device = blk_get_attached_dev(blk);
if (has_device && !blk_dev_has_removable_media(blk)) {
error_setg(errp, "Device is not removable");
return;
}
if (has_device && blk_dev_has_tray(blk) && !blk_dev_is_tray_open(blk)) {
error_setg(errp, "Tray of the device is not open");
return;
}
if (blk_bs(blk)) {
error_setg(errp, "There already is a medium in the device");
return;
}
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
return;
}
if (!blk_dev_has_tray(blk)) {
/* For tray-less devices, blockdev-close-tray is a no-op (or may not be
* called at all); therefore, the medium needs to be pushed into the
* slot here.
* Do it after blk_insert_bs() so blk_is_inserted(blk) returns the @load
* value passed here (i.e. true). */
blk_dev_change_media_cb(blk, true, &local_err);
if (local_err) {
error_propagate(errp, local_err);
blk_remove_bs(blk);
return;
}
}
}
void qmp_x_blockdev_insert_medium(bool has_device, const char *device,
bool has_id, const char *id,
const char *node_name, Error **errp)
{
BlockBackend *blk;
BlockDriverState *bs;
blk = qmp_get_blk(has_device ? device : NULL,
has_id ? id : NULL,
errp);
if (!blk) {
return;
}
bs = bdrv_find_node(node_name);
if (!bs) {
error_setg(errp, "Node '%s' not found", node_name);
return;
}
if (bdrv_has_blk(bs)) {
error_setg(errp, "Node '%s' is already in use", node_name);
return;
}
qmp_blockdev_insert_anon_medium(blk, bs, errp);
}
void qmp_blockdev_change_medium(bool has_device, const char *device,
bool has_id, const char *id,
const char *filename,
bool has_format, const char *format,
bool has_read_only,
BlockdevChangeReadOnlyMode read_only,
Error **errp)
{
BlockBackend *blk;
BlockDriverState *medium_bs = NULL;
int bdrv_flags;
bool detect_zeroes;
int rc;
QDict *options = NULL;
Error *err = NULL;
blk = qmp_get_blk(has_device ? device : NULL,
has_id ? id : NULL,
errp);
if (!blk) {
goto fail;
}
if (blk_bs(blk)) {
blk_update_root_state(blk);
}
bdrv_flags = blk_get_open_flags_from_root_state(blk);
bdrv_flags &= ~(BDRV_O_TEMPORARY | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING |
BDRV_O_PROTOCOL);
if (!has_read_only) {
read_only = BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN;
}
switch (read_only) {
case BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN:
break;
case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_ONLY:
bdrv_flags &= ~BDRV_O_RDWR;
break;
case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_WRITE:
bdrv_flags |= BDRV_O_RDWR;
break;
default:
abort();
}
options = qdict_new();
detect_zeroes = blk_get_detect_zeroes_from_root_state(blk);
qdict_put_str(options, "detect-zeroes", detect_zeroes ? "on" : "off");
if (has_format) {
qdict_put_str(options, "driver", format);
}
medium_bs = bdrv_open(filename, NULL, options, bdrv_flags, errp);
if (!medium_bs) {
goto fail;
}
bdrv_add_key(medium_bs, NULL, &err);
if (err) {
error_propagate(errp, err);
goto fail;
}
rc = do_open_tray(has_device ? device : NULL,
has_id ? id : NULL,
false, &err);
if (rc && rc != -ENOSYS) {
error_propagate(errp, err);
goto fail;
}
error_free(err);
err = NULL;
qmp_x_blockdev_remove_medium(has_device, device, has_id, id, &err);
if (err) {
error_propagate(errp, err);
goto fail;
}
qmp_blockdev_insert_anon_medium(blk, medium_bs, &err);
if (err) {
error_propagate(errp, err);
goto fail;
}
qmp_blockdev_close_tray(has_device, device, has_id, id, errp);
fail:
/* If the medium has been inserted, the device has its own reference, so
* ours must be relinquished; and if it has not been inserted successfully,
* the reference must be relinquished anyway */
bdrv_unref(medium_bs);
}
/* throttling disk I/O limits */
void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
{
ThrottleConfig cfg;
BlockDriverState *bs;
BlockBackend *blk;
AioContext *aio_context;
blk = qmp_get_blk(arg->has_device ? arg->device : NULL,
arg->has_id ? arg->id : NULL,
errp);
if (!blk) {
return;
}
aio_context = blk_get_aio_context(blk);
aio_context_acquire(aio_context);
bs = blk_bs(blk);
if (!bs) {
error_setg(errp, "Device has no medium");
goto out;
}
throttle_config_init(&cfg);
cfg.buckets[THROTTLE_BPS_TOTAL].avg = arg->bps;
cfg.buckets[THROTTLE_BPS_READ].avg = arg->bps_rd;
cfg.buckets[THROTTLE_BPS_WRITE].avg = arg->bps_wr;
cfg.buckets[THROTTLE_OPS_TOTAL].avg = arg->iops;
cfg.buckets[THROTTLE_OPS_READ].avg = arg->iops_rd;
cfg.buckets[THROTTLE_OPS_WRITE].avg = arg->iops_wr;
if (arg->has_bps_max) {
cfg.buckets[THROTTLE_BPS_TOTAL].max = arg->bps_max;
}
if (arg->has_bps_rd_max) {
cfg.buckets[THROTTLE_BPS_READ].max = arg->bps_rd_max;
}
if (arg->has_bps_wr_max) {
cfg.buckets[THROTTLE_BPS_WRITE].max = arg->bps_wr_max;
}
if (arg->has_iops_max) {
cfg.buckets[THROTTLE_OPS_TOTAL].max = arg->iops_max;
}
if (arg->has_iops_rd_max) {
cfg.buckets[THROTTLE_OPS_READ].max = arg->iops_rd_max;
}
if (arg->has_iops_wr_max) {
cfg.buckets[THROTTLE_OPS_WRITE].max = arg->iops_wr_max;
}
if (arg->has_bps_max_length) {
cfg.buckets[THROTTLE_BPS_TOTAL].burst_length = arg->bps_max_length;
}
if (arg->has_bps_rd_max_length) {
cfg.buckets[THROTTLE_BPS_READ].burst_length = arg->bps_rd_max_length;
}
if (arg->has_bps_wr_max_length) {
cfg.buckets[THROTTLE_BPS_WRITE].burst_length = arg->bps_wr_max_length;
}
if (arg->has_iops_max_length) {
cfg.buckets[THROTTLE_OPS_TOTAL].burst_length = arg->iops_max_length;
}
if (arg->has_iops_rd_max_length) {
cfg.buckets[THROTTLE_OPS_READ].burst_length = arg->iops_rd_max_length;
}
if (arg->has_iops_wr_max_length) {
cfg.buckets[THROTTLE_OPS_WRITE].burst_length = arg->iops_wr_max_length;
}
if (arg->has_iops_size) {
cfg.op_size = arg->iops_size;
}
if (!throttle_is_valid(&cfg, errp)) {
goto out;
}
if (throttle_enabled(&cfg)) {
/* Enable I/O limits if they're not enabled yet, otherwise
* just update the throttling group. */
if (!blk_get_public(blk)->throttle_state) {
blk_io_limits_enable(blk,
arg->has_group ? arg->group :
arg->has_device ? arg->device :
arg->id);
} else if (arg->has_group) {
blk_io_limits_update_group(blk, arg->group);
}
/* Set the new throttling configuration */
blk_set_io_limits(blk, &cfg);
} else if (blk_get_public(blk)->throttle_state) {
/* If all throttling settings are set to 0, disable I/O limits */
blk_io_limits_disable(blk);
}
out:
aio_context_release(aio_context);
}
void qmp_block_dirty_bitmap_add(const char *node, const char *name,
bool has_granularity, uint32_t granularity,
Error **errp)
{
BlockDriverState *bs;
if (!name || name[0] == '\0') {
error_setg(errp, "Bitmap name cannot be empty");
return;
}
bs = bdrv_lookup_bs(node, node, errp);
if (!bs) {
return;
}
if (has_granularity) {
if (granularity < 512 || !is_power_of_2(granularity)) {
error_setg(errp, "Granularity must be power of 2 "
"and at least 512");
return;
}
} else {
/* Default to cluster size, if available: */
granularity = bdrv_get_default_bitmap_granularity(bs);
}
bdrv_create_dirty_bitmap(bs, granularity, name, errp);
}
void qmp_block_dirty_bitmap_remove(const char *node, const char *name,
Error **errp)
{
BlockDriverState *bs;
BdrvDirtyBitmap *bitmap;
bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
if (!bitmap || !bs) {
return;
}
block: Add bitmap successors A bitmap successor is an anonymous BdrvDirtyBitmap that is intended to be created just prior to a sensitive operation (e.g. Incremental Backup) that can either succeed or fail, but during the course of which we still want a bitmap tracking writes. On creating a successor, we "freeze" the parent bitmap which prevents its deletion, enabling, anonymization, or creating a bitmap with the same name. On success, the parent bitmap can "abdicate" responsibility to the successor, which will inherit its name. The successor will have been tracking writes during the course of the backup operation. The parent will be safely deleted. On failure, we can "reclaim" the successor from the parent, unifying them such that the resulting bitmap describes all writes occurring since the last successful backup, for instance. Reclamation will thaw the parent, but not explicitly re-enable it. BdrvDirtyBitmap operations that target a single bitmap are protected by assertions that the bitmap is not frozen and/or disabled. BdrvDirtyBitmap operations that target a group of bitmaps, such as bdrv_{set,reset}_dirty will ignore frozen/disabled drives with a conditional instead. Internal functions that enable/disable dirty bitmaps have assertions added to them to prevent modifying frozen bitmaps. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1429314609-29776-10-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-18 01:49:57 +02:00
if (bdrv_dirty_bitmap_frozen(bitmap)) {
error_setg(errp,
"Bitmap '%s' is currently frozen and cannot be removed",
name);
return;
block: Add bitmap successors A bitmap successor is an anonymous BdrvDirtyBitmap that is intended to be created just prior to a sensitive operation (e.g. Incremental Backup) that can either succeed or fail, but during the course of which we still want a bitmap tracking writes. On creating a successor, we "freeze" the parent bitmap which prevents its deletion, enabling, anonymization, or creating a bitmap with the same name. On success, the parent bitmap can "abdicate" responsibility to the successor, which will inherit its name. The successor will have been tracking writes during the course of the backup operation. The parent will be safely deleted. On failure, we can "reclaim" the successor from the parent, unifying them such that the resulting bitmap describes all writes occurring since the last successful backup, for instance. Reclamation will thaw the parent, but not explicitly re-enable it. BdrvDirtyBitmap operations that target a single bitmap are protected by assertions that the bitmap is not frozen and/or disabled. BdrvDirtyBitmap operations that target a group of bitmaps, such as bdrv_{set,reset}_dirty will ignore frozen/disabled drives with a conditional instead. Internal functions that enable/disable dirty bitmaps have assertions added to them to prevent modifying frozen bitmaps. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1429314609-29776-10-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-18 01:49:57 +02:00
}
bdrv_dirty_bitmap_make_anon(bitmap);
bdrv_release_dirty_bitmap(bs, bitmap);
}
/**
* Completely clear a bitmap, for the purposes of synchronizing a bitmap
* immediately after a full backup operation.
*/
void qmp_block_dirty_bitmap_clear(const char *node, const char *name,
Error **errp)
{
BdrvDirtyBitmap *bitmap;
BlockDriverState *bs;
bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
if (!bitmap || !bs) {
return;
}
if (bdrv_dirty_bitmap_frozen(bitmap)) {
error_setg(errp,
"Bitmap '%s' is currently frozen and cannot be modified",
name);
return;
} else if (!bdrv_dirty_bitmap_enabled(bitmap)) {
error_setg(errp,
"Bitmap '%s' is currently disabled and cannot be cleared",
name);
return;
}
bdrv_clear_dirty_bitmap(bitmap, NULL);
}
void hmp_drive_del(Monitor *mon, const QDict *qdict)
{
const char *id = qdict_get_str(qdict, "id");
BlockBackend *blk;
BlockDriverState *bs;
AioContext *aio_context;
Error *local_err = NULL;
bs = bdrv_find_node(id);
if (bs) {
qmp_blockdev_del(id, &local_err);
if (local_err) {
error_report_err(local_err);
}
return;
}
blk = blk_by_name(id);
if (!blk) {
error_report("Device '%s' not found", id);
return;
}
if (!blk_legacy_dinfo(blk)) {
error_report("Deleting device added with blockdev-add"
" is not supported");
return;
}
aio_context = blk_get_aio_context(blk);
aio_context_acquire(aio_context);
bs = blk_bs(blk);
if (bs) {
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, &local_err)) {
error_report_err(local_err);
aio_context_release(aio_context);
return;
}
blk_remove_bs(blk);
}
/* Make the BlockBackend and the attached BlockDriverState anonymous */
monitor_remove_blk(blk);
/* If this BlockBackend has a device attached to it, its refcount will be
* decremented when the device is removed; otherwise we have to do so here.
Do not delete BlockDriverState when deleting the drive When removing a drive from the host-side via drive_del we currently have the following path: drive_del qemu_aio_flush() bdrv_close() // zaps bs->drv, which makes any subsequent I/O get // dropped. Works as designed drive_uninit() bdrv_delete() // frees the bs. Since the device is still connected to // bs, any subsequent I/O is a use-after-free. The value of bs->drv becomes unpredictable on free. As long as it remains null, I/O still gets dropped, however it could become non-null at any point after the free resulting SEGVs or other QEMU state corruption. To resolve this issue as simply as possible, we can chose to not actually delete the BlockDriverState pointer. Since bdrv_close() handles setting the drv pointer to NULL, we just need to remove the BlockDriverState from the QLIST that is used to enumerate the block devices. This is currently handled within bdrv_delete, so move this into its own function, bdrv_make_anon(). The result is that we can now invoke drive_del, this closes the file descriptors and sets BlockDriverState->drv to NULL which prevents futher IO to the device, and since we do not free BlockDriverState, we don't have to worry about the copy retained in the block devices. We also don't attempt to remove the qdev property since we are no longer deleting the BlockDriverState on drives with associated drives. This also allows for removing Drives with no devices associated either. Reported-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Ryan Harper <ryanh@us.ibm.com> Acked-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-03-30 03:51:47 +02:00
*/
if (blk_get_attached_dev(blk)) {
/* Further I/O must not pause the guest */
blk_set_on_error(blk, BLOCKDEV_ON_ERROR_REPORT,
BLOCKDEV_ON_ERROR_REPORT);
Do not delete BlockDriverState when deleting the drive When removing a drive from the host-side via drive_del we currently have the following path: drive_del qemu_aio_flush() bdrv_close() // zaps bs->drv, which makes any subsequent I/O get // dropped. Works as designed drive_uninit() bdrv_delete() // frees the bs. Since the device is still connected to // bs, any subsequent I/O is a use-after-free. The value of bs->drv becomes unpredictable on free. As long as it remains null, I/O still gets dropped, however it could become non-null at any point after the free resulting SEGVs or other QEMU state corruption. To resolve this issue as simply as possible, we can chose to not actually delete the BlockDriverState pointer. Since bdrv_close() handles setting the drv pointer to NULL, we just need to remove the BlockDriverState from the QLIST that is used to enumerate the block devices. This is currently handled within bdrv_delete, so move this into its own function, bdrv_make_anon(). The result is that we can now invoke drive_del, this closes the file descriptors and sets BlockDriverState->drv to NULL which prevents futher IO to the device, and since we do not free BlockDriverState, we don't have to worry about the copy retained in the block devices. We also don't attempt to remove the qdev property since we are no longer deleting the BlockDriverState on drives with associated drives. This also allows for removing Drives with no devices associated either. Reported-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Ryan Harper <ryanh@us.ibm.com> Acked-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-03-30 03:51:47 +02:00
} else {
blk_unref(blk);
}
aio_context_release(aio_context);
}
void qmp_block_resize(bool has_device, const char *device,
bool has_node_name, const char *node_name,
int64_t size, Error **errp)
{
Error *local_err = NULL;
BlockBackend *blk = NULL;
BlockDriverState *bs;
AioContext *aio_context;
int ret;
bs = bdrv_lookup_bs(has_device ? device : NULL,
has_node_name ? node_name : NULL,
&local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (!bdrv_is_first_non_filter(bs)) {
error_setg(errp, QERR_FEATURE_DISABLED, "resize");
goto out;
}
if (size < 0) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
goto out;
}
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, NULL)) {
error_setg(errp, QERR_DEVICE_IN_USE, device);
goto out;
}
blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL);
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
goto out;
}
bdrv_drained_begin(bs);
ret = blk_truncate(blk, size, errp);
bdrv_drained_end(bs);
out:
blk_unref(blk);
aio_context_release(aio_context);
}
void qmp_block_stream(bool has_job_id, const char *job_id, const char *device,
bool has_base, const char *base,
bool has_base_node, const char *base_node,
bool has_backing_file, const char *backing_file,
bool has_speed, int64_t speed,
bool has_on_error, BlockdevOnError on_error,
Error **errp)
{
BlockDriverState *bs, *iter;
BlockDriverState *base_bs = NULL;
AioContext *aio_context;
Error *local_err = NULL;
const char *base_name = NULL;
if (!has_on_error) {
on_error = BLOCKDEV_ON_ERROR_REPORT;
}
bs = bdrv_lookup_bs(device, device, errp);
if (!bs) {
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (has_base && has_base_node) {
error_setg(errp, "'base' and 'base-node' cannot be specified "
"at the same time");
goto out;
}
if (has_base) {
base_bs = bdrv_find_backing_image(bs, base);
if (base_bs == NULL) {
error_setg(errp, QERR_BASE_NOT_FOUND, base);
goto out;
}
assert(bdrv_get_aio_context(base_bs) == aio_context);
base_name = base;
}
if (has_base_node) {
base_bs = bdrv_lookup_bs(NULL, base_node, errp);
if (!base_bs) {
goto out;
}
if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
error_setg(errp, "Node '%s' is not a backing image of '%s'",
base_node, device);
goto out;
}
assert(bdrv_get_aio_context(base_bs) == aio_context);
base_name = base_bs->filename;
}
/* Check for op blockers in the whole chain between bs and base */
for (iter = bs; iter && iter != base_bs; iter = backing_bs(iter)) {
if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
goto out;
}
}
/* if we are streaming the entire chain, the result will have no backing
* file, and specifying one is therefore an error */
if (base_bs == NULL && has_backing_file) {
error_setg(errp, "backing file specified, but streaming the "
"entire chain");
goto out;
}
/* backing_file string overrides base bs filename */
base_name = has_backing_file ? backing_file : base_name;
stream_start(has_job_id ? job_id : NULL, bs, base_bs, base_name,
has_speed ? speed : 0, on_error, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out;
}
trace_qmp_block_stream(bs, bs->job);
out:
aio_context_release(aio_context);
}
void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
bool has_base, const char *base,
bool has_top, const char *top,
bool has_backing_file, const char *backing_file,
bool has_speed, int64_t speed,
bool has_filter_node_name, const char *filter_node_name,
Error **errp)
{
BlockDriverState *bs;
BlockDriverState *iter;
BlockDriverState *base_bs, *top_bs;
AioContext *aio_context;
Error *local_err = NULL;
/* This will be part of the QMP command, if/when the
* BlockdevOnError change for blkmirror makes it in
*/
BlockdevOnError on_error = BLOCKDEV_ON_ERROR_REPORT;
if (!has_speed) {
speed = 0;
}
if (!has_filter_node_name) {
filter_node_name = NULL;
}
/* Important Note:
* libvirt relies on the DeviceNotFound error class in order to probe for
* live commit feature versions; for this to work, we must make sure to
* perform the device lookup before any generic errors that may occur in a
* scenario in which all optional arguments are omitted. */
bs = qmp_get_root_bs(device, &local_err);
if (!bs) {
bs = bdrv_lookup_bs(device, device, NULL);
if (!bs) {
error_free(local_err);
error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
"Device '%s' not found", device);
} else {
error_propagate(errp, local_err);
}
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, errp)) {
goto out;
}
/* default top_bs is the active layer */
top_bs = bs;
if (has_top && top) {
if (strcmp(bs->filename, top) != 0) {
top_bs = bdrv_find_backing_image(bs, top);
}
}
if (top_bs == NULL) {
error_setg(errp, "Top image file %s not found", top ? top : "NULL");
goto out;
}
assert(bdrv_get_aio_context(top_bs) == aio_context);
if (has_base && base) {
base_bs = bdrv_find_backing_image(top_bs, base);
} else {
base_bs = bdrv_find_base(top_bs);
}
if (base_bs == NULL) {
error_setg(errp, QERR_BASE_NOT_FOUND, base ? base : "NULL");
goto out;
}
assert(bdrv_get_aio_context(base_bs) == aio_context);
for (iter = top_bs; iter != backing_bs(base_bs); iter = backing_bs(iter)) {
if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
goto out;
}
}
/* Do not allow attempts to commit an image into itself */
if (top_bs == base_bs) {
error_setg(errp, "cannot commit an image into itself");
goto out;
}
if (top_bs == bs) {
if (has_backing_file) {
error_setg(errp, "'backing-file' specified,"
" but 'top' is the active layer");
goto out;
}
commit_active_start(has_job_id ? job_id : NULL, bs, base_bs,
BLOCK_JOB_DEFAULT, speed, on_error,
filter_node_name, NULL, NULL, false, &local_err);
} else {
BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
goto out;
}
commit_start(has_job_id ? job_id : NULL, bs, base_bs, top_bs, speed,
on_error, has_backing_file ? backing_file : NULL,
filter_node_name, &local_err);
}
if (local_err != NULL) {
error_propagate(errp, local_err);
goto out;
}
out:
aio_context_release(aio_context);
}
static BlockJob *do_drive_backup(DriveBackup *backup, BlockJobTxn *txn,
Error **errp)
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
{
BlockDriverState *bs;
BlockDriverState *target_bs;
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
BlockDriverState *source = NULL;
BlockJob *job = NULL;
BdrvDirtyBitmap *bmap = NULL;
AioContext *aio_context;
QDict *options = NULL;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
Error *local_err = NULL;
int flags;
int64_t size;
bool set_backing_hd = false;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
if (!backup->has_speed) {
backup->speed = 0;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
if (!backup->has_on_source_error) {
backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
if (!backup->has_on_target_error) {
backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
if (!backup->has_mode) {
backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
}
if (!backup->has_job_id) {
backup->job_id = NULL;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
if (!backup->has_compress) {
backup->compress = false;
}
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
bs = qmp_get_root_bs(backup->device, errp);
if (!bs) {
return NULL;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (!backup->has_format) {
backup->format = backup->mode == NEW_IMAGE_MODE_EXISTING ?
NULL : (char*) bs->drv->format_name;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
/* Early check to avoid creating target */
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
goto out;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
flags = bs->open_flags | BDRV_O_RDWR;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
/* See if we have a backing HD we can use to create our new image
* on top of. */
if (backup->sync == MIRROR_SYNC_MODE_TOP) {
source = backing_bs(bs);
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
if (!source) {
backup->sync = MIRROR_SYNC_MODE_FULL;
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
}
}
if (backup->sync == MIRROR_SYNC_MODE_NONE) {
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
source = bs;
flags |= BDRV_O_NO_BACKING;
set_backing_hd = true;
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
}
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
size = bdrv_getlength(bs);
if (size < 0) {
error_setg_errno(errp, -size, "bdrv_getlength failed");
goto out;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
if (backup->mode != NEW_IMAGE_MODE_EXISTING) {
assert(backup->format);
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
if (source) {
bdrv_img_create(backup->target, backup->format, source->filename,
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
source->drv->format_name, NULL,
size, flags, false, &local_err);
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
} else {
bdrv_img_create(backup->target, backup->format, NULL, NULL, NULL,
size, flags, false, &local_err);
Implement sync modes for drive-backup. This patch adds sync-modes to the drive-backup interface and implements the FULL, NONE and TOP modes of synchronization. FULL performs as before copying the entire contents of the drive while preserving the point-in-time using CoW. NONE only copies new writes to the target drive. TOP copies changes to the topmost drive image and preserves the point-in-time using CoW. For sync mode TOP are creating a new target image using the same backing file as the original disk image. Then any new data that has been laid on top of it since creation is copied in the main backup_run() loop. There is an extra check in the 'TOP' case so that we don't bother to copy all the data of the backing file as it already exists in the target. This is where the bdrv_co_is_allocated() is used to determine if the data exists in the topmost layer or below. Also any new data being written is intercepted via the write_notifier hook which ends up calling backup_do_cow() to copy old data out before it gets overwritten. For mode 'NONE' we create the new target image and only copy in the original data from the disk image starting from the time the call was made. This preserves the point in time data by only copying the parts that are *going to change* to the target image. This way we can reconstruct the final image by checking to see if the given block exists in the new target image first, and if it does not, you can get it from the original image. This is basically an optimization allowing you to do point-in-time snapshots with low overhead vs the 'FULL' version. Since there is no old data to copy out the loop in backup_run() for the NONE case just calls qemu_coroutine_yield() which only wakes up after an event (usually cancel in this case). The rest is handled by the before_write notifier which again calls backup_do_cow() to write out the old data so it can be preserved. Signed-off-by: Ian Main <imain@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 20:39:04 +02:00
}
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
if (local_err) {
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
error_propagate(errp, local_err);
goto out;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
if (backup->format) {
if (!options) {
options = qdict_new();
}
qdict_put_str(options, "driver", backup->format);
}
target_bs = bdrv_open(backup->target, NULL, options, flags, errp);
if (!target_bs) {
goto out;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
bdrv_set_aio_context(target_bs, aio_context);
if (set_backing_hd) {
bdrv_set_backing_hd(target_bs, source, &local_err);
if (local_err) {
bdrv_unref(target_bs);
goto out;
}
}
if (backup->has_bitmap) {
bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
if (!bmap) {
error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
bdrv_unref(target_bs);
goto out;
}
}
job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
backup->sync, bmap, backup->compress,
backup->on_source_error, backup->on_target_error,
BLOCK_JOB_DEFAULT, NULL, NULL, txn, &local_err);
bdrv_unref(target_bs);
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
if (local_err != NULL) {
error_propagate(errp, local_err);
goto out;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
out:
aio_context_release(aio_context);
return job;
block: add drive-backup QMP command @drive-backup Start a point-in-time copy of a block device to a new destination. The status of ongoing drive-backup operations can be checked with query-block-jobs where the BlockJobInfo.type field has the value 'backup'. The operation can be stopped before it has completed using the block-job-cancel command. @device: the name of the device which should be copied. @target: the target of the new image. If the file exists, or if it is a device, the existing file/device will be used as the new destination. If it does not exist, a new file will be created. @format: #optional the format of the new destination, default is to probe if @mode is 'existing', else the format of the source @mode: #optional whether and how QEMU should create a new image, default is 'absolute-paths'. @speed: #optional the maximum speed, in bytes per second @on-source-error: #optional the action to take on an error on the source, default 'report'. 'stop' and 'enospc' can only be used if the block device supports io-status (see BlockInfo). @on-target-error: #optional the action to take on an error on the target, default 'report' (no limitations, since this applies to a different block device than @device). Note that @on-source-error and @on-target-error only affect background I/O. If an error occurs during a guest write request, the device's rerror/werror actions will be used. Returns: nothing on success If @device is not a valid block device, DeviceNotFound Since 1.6 Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-24 17:13:14 +02:00
}
void qmp_drive_backup(DriveBackup *arg, Error **errp)
{
BlockJob *job;
job = do_drive_backup(arg, NULL, errp);
if (job) {
block_job_start(job);
}
}
BlockDeviceInfoList *qmp_query_named_block_nodes(Error **errp)
{
return bdrv_named_nodes_list(errp);
}
BlockJob *do_blockdev_backup(BlockdevBackup *backup, BlockJobTxn *txn,
Error **errp)
{
BlockDriverState *bs;
BlockDriverState *target_bs;
Error *local_err = NULL;
AioContext *aio_context;
BlockJob *job = NULL;
if (!backup->has_speed) {
backup->speed = 0;
}
if (!backup->has_on_source_error) {
backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
}
if (!backup->has_on_target_error) {
backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
}
if (!backup->has_job_id) {
backup->job_id = NULL;
}
if (!backup->has_compress) {
backup->compress = false;
}
bs = qmp_get_root_bs(backup->device, errp);
if (!bs) {
return NULL;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
target_bs = bdrv_lookup_bs(backup->target, backup->target, errp);
if (!target_bs) {
goto out;
}
if (bdrv_get_aio_context(target_bs) != aio_context) {
if (!bdrv_has_blk(target_bs)) {
/* The target BDS is not attached, we can safely move it to another
* AioContext. */
bdrv_set_aio_context(target_bs, aio_context);
} else {
error_setg(errp, "Target is attached to a different thread from "
"source.");
goto out;
}
}
job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
backup->sync, NULL, backup->compress,
backup->on_source_error, backup->on_target_error,
BLOCK_JOB_DEFAULT, NULL, NULL, txn, &local_err);
if (local_err != NULL) {
error_propagate(errp, local_err);
}
out:
aio_context_release(aio_context);
return job;
}
void qmp_blockdev_backup(BlockdevBackup *arg, Error **errp)
{
BlockJob *job;
job = do_blockdev_backup(arg, NULL, errp);
if (job) {
block_job_start(job);
}
}
/* Parameter check and block job starting for drive mirroring.
* Caller should hold @device and @target's aio context (must be the same).
**/
static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
BlockDriverState *target,
bool has_replaces, const char *replaces,
enum MirrorSyncMode sync,
block/mirror: Fix target backing BDS Currently, we are trying to move the backing BDS from the source to the target in bdrv_replace_in_backing_chain() which is called from mirror_exit(). However, mirror_complete() already tries to open the target's backing chain with a call to bdrv_open_backing_file(). First, we should only set the target's backing BDS once. Second, the mirroring block job has a better idea of what to set it to than the generic code in bdrv_replace_in_backing_chain() (in fact, the latter's conditions on when to move the backing BDS from source to target are not really correct). Therefore, remove that code from bdrv_replace_in_backing_chain() and leave it to mirror_complete(). Depending on what kind of mirroring is performed, we furthermore want to use different strategies to open the target's backing chain: - If blockdev-mirror is used, we can assume the user made sure that the target already has the correct backing chain. In particular, we should not try to open a backing file if the target does not have any yet. - If drive-mirror with mode=absolute-paths is used, we can and should reuse the already existing chain of nodes that the source BDS is in. In case of sync=full, no backing BDS is required; with sync=top, we just link the source's backing BDS to the target, and with sync=none, we use the source BDS as the target's backing BDS. We should not try to open these backing files anew because this would lead to two BDSs existing per physical file in the backing chain, and we would like to avoid such concurrent access. - If drive-mirror with mode=existing is used, we have to use the information provided in the physical image file which means opening the target's backing chain completely anew, just as it has been done already. If the target's backing chain shares images with the source, this may lead to multiple BDSs per physical image file. But since we cannot reliably ascertain this case, there is nothing we can do about it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-3-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-10 20:57:47 +02:00
BlockMirrorBackingMode backing_mode,
bool has_speed, int64_t speed,
bool has_granularity, uint32_t granularity,
bool has_buf_size, int64_t buf_size,
bool has_on_source_error,
BlockdevOnError on_source_error,
bool has_on_target_error,
BlockdevOnError on_target_error,
bool has_unmap, bool unmap,
bool has_filter_node_name,
const char *filter_node_name,
Error **errp)
{
if (!has_speed) {
speed = 0;
}
if (!has_on_source_error) {
on_source_error = BLOCKDEV_ON_ERROR_REPORT;
}
if (!has_on_target_error) {
on_target_error = BLOCKDEV_ON_ERROR_REPORT;
}
if (!has_granularity) {
granularity = 0;
}
if (!has_buf_size) {
buf_size = 0;
}
if (!has_unmap) {
unmap = true;
}
if (!has_filter_node_name) {
filter_node_name = NULL;
}
if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
"a value in range [512B, 64MB]");
return;
}
if (granularity & (granularity - 1)) {
error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
"power of 2");
return;
}
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
return;
}
if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_MIRROR_TARGET, errp)) {
return;
}
if (!bs->backing && sync == MIRROR_SYNC_MODE_TOP) {
sync = MIRROR_SYNC_MODE_FULL;
}
/* pass the node name to replace to mirror start since it's loose coupling
* and will allow to check whether the node still exist at mirror completion
*/
mirror_start(job_id, bs, target,
has_replaces ? replaces : NULL,
block/mirror: Fix target backing BDS Currently, we are trying to move the backing BDS from the source to the target in bdrv_replace_in_backing_chain() which is called from mirror_exit(). However, mirror_complete() already tries to open the target's backing chain with a call to bdrv_open_backing_file(). First, we should only set the target's backing BDS once. Second, the mirroring block job has a better idea of what to set it to than the generic code in bdrv_replace_in_backing_chain() (in fact, the latter's conditions on when to move the backing BDS from source to target are not really correct). Therefore, remove that code from bdrv_replace_in_backing_chain() and leave it to mirror_complete(). Depending on what kind of mirroring is performed, we furthermore want to use different strategies to open the target's backing chain: - If blockdev-mirror is used, we can assume the user made sure that the target already has the correct backing chain. In particular, we should not try to open a backing file if the target does not have any yet. - If drive-mirror with mode=absolute-paths is used, we can and should reuse the already existing chain of nodes that the source BDS is in. In case of sync=full, no backing BDS is required; with sync=top, we just link the source's backing BDS to the target, and with sync=none, we use the source BDS as the target's backing BDS. We should not try to open these backing files anew because this would lead to two BDSs existing per physical file in the backing chain, and we would like to avoid such concurrent access. - If drive-mirror with mode=existing is used, we have to use the information provided in the physical image file which means opening the target's backing chain completely anew, just as it has been done already. If the target's backing chain shares images with the source, this may lead to multiple BDSs per physical image file. But since we cannot reliably ascertain this case, there is nothing we can do about it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-3-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-10 20:57:47 +02:00
speed, granularity, buf_size, sync, backing_mode,
on_source_error, on_target_error, unmap, filter_node_name,
errp);
}
void qmp_drive_mirror(DriveMirror *arg, Error **errp)
{
BlockDriverState *bs;
BlockDriverState *source, *target_bs;
AioContext *aio_context;
block/mirror: Fix target backing BDS Currently, we are trying to move the backing BDS from the source to the target in bdrv_replace_in_backing_chain() which is called from mirror_exit(). However, mirror_complete() already tries to open the target's backing chain with a call to bdrv_open_backing_file(). First, we should only set the target's backing BDS once. Second, the mirroring block job has a better idea of what to set it to than the generic code in bdrv_replace_in_backing_chain() (in fact, the latter's conditions on when to move the backing BDS from source to target are not really correct). Therefore, remove that code from bdrv_replace_in_backing_chain() and leave it to mirror_complete(). Depending on what kind of mirroring is performed, we furthermore want to use different strategies to open the target's backing chain: - If blockdev-mirror is used, we can assume the user made sure that the target already has the correct backing chain. In particular, we should not try to open a backing file if the target does not have any yet. - If drive-mirror with mode=absolute-paths is used, we can and should reuse the already existing chain of nodes that the source BDS is in. In case of sync=full, no backing BDS is required; with sync=top, we just link the source's backing BDS to the target, and with sync=none, we use the source BDS as the target's backing BDS. We should not try to open these backing files anew because this would lead to two BDSs existing per physical file in the backing chain, and we would like to avoid such concurrent access. - If drive-mirror with mode=existing is used, we have to use the information provided in the physical image file which means opening the target's backing chain completely anew, just as it has been done already. If the target's backing chain shares images with the source, this may lead to multiple BDSs per physical image file. But since we cannot reliably ascertain this case, there is nothing we can do about it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-3-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-10 20:57:47 +02:00
BlockMirrorBackingMode backing_mode;
Error *local_err = NULL;
QDict *options = NULL;
int flags;
int64_t size;
const char *format = arg->format;
bs = qmp_get_root_bs(arg->device, errp);
if (!bs) {
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (!arg->has_mode) {
arg->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
}
if (!arg->has_format) {
format = (arg->mode == NEW_IMAGE_MODE_EXISTING
? NULL : bs->drv->format_name);
}
flags = bs->open_flags | BDRV_O_RDWR;
source = backing_bs(bs);
if (!source && arg->sync == MIRROR_SYNC_MODE_TOP) {
arg->sync = MIRROR_SYNC_MODE_FULL;
}
if (arg->sync == MIRROR_SYNC_MODE_NONE) {
source = bs;
}
size = bdrv_getlength(bs);
if (size < 0) {
error_setg_errno(errp, -size, "bdrv_getlength failed");
goto out;
}
if (arg->has_replaces) {
BlockDriverState *to_replace_bs;
AioContext *replace_aio_context;
int64_t replace_size;
if (!arg->has_node_name) {
error_setg(errp, "a node-name must be provided when replacing a"
" named node of the graph");
goto out;
}
to_replace_bs = check_to_replace_node(bs, arg->replaces, &local_err);
if (!to_replace_bs) {
error_propagate(errp, local_err);
goto out;
}
replace_aio_context = bdrv_get_aio_context(to_replace_bs);
aio_context_acquire(replace_aio_context);
replace_size = bdrv_getlength(to_replace_bs);
aio_context_release(replace_aio_context);
if (size != replace_size) {
error_setg(errp, "cannot replace image with a mirror image of "
"different size");
goto out;
}
}
if (arg->mode == NEW_IMAGE_MODE_ABSOLUTE_PATHS) {
block/mirror: Fix target backing BDS Currently, we are trying to move the backing BDS from the source to the target in bdrv_replace_in_backing_chain() which is called from mirror_exit(). However, mirror_complete() already tries to open the target's backing chain with a call to bdrv_open_backing_file(). First, we should only set the target's backing BDS once. Second, the mirroring block job has a better idea of what to set it to than the generic code in bdrv_replace_in_backing_chain() (in fact, the latter's conditions on when to move the backing BDS from source to target are not really correct). Therefore, remove that code from bdrv_replace_in_backing_chain() and leave it to mirror_complete(). Depending on what kind of mirroring is performed, we furthermore want to use different strategies to open the target's backing chain: - If blockdev-mirror is used, we can assume the user made sure that the target already has the correct backing chain. In particular, we should not try to open a backing file if the target does not have any yet. - If drive-mirror with mode=absolute-paths is used, we can and should reuse the already existing chain of nodes that the source BDS is in. In case of sync=full, no backing BDS is required; with sync=top, we just link the source's backing BDS to the target, and with sync=none, we use the source BDS as the target's backing BDS. We should not try to open these backing files anew because this would lead to two BDSs existing per physical file in the backing chain, and we would like to avoid such concurrent access. - If drive-mirror with mode=existing is used, we have to use the information provided in the physical image file which means opening the target's backing chain completely anew, just as it has been done already. If the target's backing chain shares images with the source, this may lead to multiple BDSs per physical image file. But since we cannot reliably ascertain this case, there is nothing we can do about it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-3-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-10 20:57:47 +02:00
backing_mode = MIRROR_SOURCE_BACKING_CHAIN;
} else {
backing_mode = MIRROR_OPEN_BACKING_CHAIN;
}
if ((arg->sync == MIRROR_SYNC_MODE_FULL || !source)
&& arg->mode != NEW_IMAGE_MODE_EXISTING)
{
/* create new image w/o backing file */
assert(format);
bdrv_img_create(arg->target, format,
NULL, NULL, NULL, size, flags, false, &local_err);
} else {
switch (arg->mode) {
case NEW_IMAGE_MODE_EXISTING:
break;
case NEW_IMAGE_MODE_ABSOLUTE_PATHS:
/* create new image with backing file */
bdrv_img_create(arg->target, format,
source->filename,
source->drv->format_name,
NULL, size, flags, false, &local_err);
break;
default:
abort();
}
}
if (local_err) {
error_propagate(errp, local_err);
goto out;
}
options = qdict_new();
if (arg->has_node_name) {
qdict_put_str(options, "node-name", arg->node_name);
}
if (format) {
qdict_put_str(options, "driver", format);
}
/* Mirroring takes care of copy-on-write using the source's backing
* file.
*/
target_bs = bdrv_open(arg->target, NULL, options,
flags | BDRV_O_NO_BACKING, errp);
if (!target_bs) {
goto out;
}
bdrv_set_aio_context(target_bs, aio_context);
blockdev_mirror_common(arg->has_job_id ? arg->job_id : NULL, bs, target_bs,
arg->has_replaces, arg->replaces, arg->sync,
backing_mode, arg->has_speed, arg->speed,
arg->has_granularity, arg->granularity,
arg->has_buf_size, arg->buf_size,
arg->has_on_source_error, arg->on_source_error,
arg->has_on_target_error, arg->on_target_error,
arg->has_unmap, arg->unmap,
false, NULL,
&local_err);
bdrv_unref(target_bs);
error_propagate(errp, local_err);
out:
aio_context_release(aio_context);
}
void qmp_blockdev_mirror(bool has_job_id, const char *job_id,
const char *device, const char *target,
bool has_replaces, const char *replaces,
MirrorSyncMode sync,
bool has_speed, int64_t speed,
bool has_granularity, uint32_t granularity,
bool has_buf_size, int64_t buf_size,
bool has_on_source_error,
BlockdevOnError on_source_error,
bool has_on_target_error,
BlockdevOnError on_target_error,
bool has_filter_node_name,
const char *filter_node_name,
Error **errp)
{
BlockDriverState *bs;
BlockDriverState *target_bs;
AioContext *aio_context;
block/mirror: Fix target backing BDS Currently, we are trying to move the backing BDS from the source to the target in bdrv_replace_in_backing_chain() which is called from mirror_exit(). However, mirror_complete() already tries to open the target's backing chain with a call to bdrv_open_backing_file(). First, we should only set the target's backing BDS once. Second, the mirroring block job has a better idea of what to set it to than the generic code in bdrv_replace_in_backing_chain() (in fact, the latter's conditions on when to move the backing BDS from source to target are not really correct). Therefore, remove that code from bdrv_replace_in_backing_chain() and leave it to mirror_complete(). Depending on what kind of mirroring is performed, we furthermore want to use different strategies to open the target's backing chain: - If blockdev-mirror is used, we can assume the user made sure that the target already has the correct backing chain. In particular, we should not try to open a backing file if the target does not have any yet. - If drive-mirror with mode=absolute-paths is used, we can and should reuse the already existing chain of nodes that the source BDS is in. In case of sync=full, no backing BDS is required; with sync=top, we just link the source's backing BDS to the target, and with sync=none, we use the source BDS as the target's backing BDS. We should not try to open these backing files anew because this would lead to two BDSs existing per physical file in the backing chain, and we would like to avoid such concurrent access. - If drive-mirror with mode=existing is used, we have to use the information provided in the physical image file which means opening the target's backing chain completely anew, just as it has been done already. If the target's backing chain shares images with the source, this may lead to multiple BDSs per physical image file. But since we cannot reliably ascertain this case, there is nothing we can do about it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-3-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-10 20:57:47 +02:00
BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
Error *local_err = NULL;
bs = qmp_get_root_bs(device, errp);
if (!bs) {
return;
}
target_bs = bdrv_lookup_bs(target, target, errp);
if (!target_bs) {
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
bdrv_set_aio_context(target_bs, aio_context);
blockdev_mirror_common(has_job_id ? job_id : NULL, bs, target_bs,
block/mirror: Fix target backing BDS Currently, we are trying to move the backing BDS from the source to the target in bdrv_replace_in_backing_chain() which is called from mirror_exit(). However, mirror_complete() already tries to open the target's backing chain with a call to bdrv_open_backing_file(). First, we should only set the target's backing BDS once. Second, the mirroring block job has a better idea of what to set it to than the generic code in bdrv_replace_in_backing_chain() (in fact, the latter's conditions on when to move the backing BDS from source to target are not really correct). Therefore, remove that code from bdrv_replace_in_backing_chain() and leave it to mirror_complete(). Depending on what kind of mirroring is performed, we furthermore want to use different strategies to open the target's backing chain: - If blockdev-mirror is used, we can assume the user made sure that the target already has the correct backing chain. In particular, we should not try to open a backing file if the target does not have any yet. - If drive-mirror with mode=absolute-paths is used, we can and should reuse the already existing chain of nodes that the source BDS is in. In case of sync=full, no backing BDS is required; with sync=top, we just link the source's backing BDS to the target, and with sync=none, we use the source BDS as the target's backing BDS. We should not try to open these backing files anew because this would lead to two BDSs existing per physical file in the backing chain, and we would like to avoid such concurrent access. - If drive-mirror with mode=existing is used, we have to use the information provided in the physical image file which means opening the target's backing chain completely anew, just as it has been done already. If the target's backing chain shares images with the source, this may lead to multiple BDSs per physical image file. But since we cannot reliably ascertain this case, there is nothing we can do about it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-3-mreitz@redhat.com Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-06-10 20:57:47 +02:00
has_replaces, replaces, sync, backing_mode,
has_speed, speed,
has_granularity, granularity,
has_buf_size, buf_size,
has_on_source_error, on_source_error,
has_on_target_error, on_target_error,
true, true,
has_filter_node_name, filter_node_name,
&local_err);
error_propagate(errp, local_err);
aio_context_release(aio_context);
}
/* Get a block job using its ID and acquire its AioContext */
static BlockJob *find_block_job(const char *id, AioContext **aio_context,
Error **errp)
{
BlockJob *job;
assert(id != NULL);
*aio_context = NULL;
job = block_job_get(id);
if (!job) {
error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
"Block job '%s' not found", id);
return NULL;
}
*aio_context = blk_get_aio_context(job->blk);
aio_context_acquire(*aio_context);
return job;
}
void qmp_block_job_set_speed(const char *device, int64_t speed, Error **errp)
{
AioContext *aio_context;
BlockJob *job = find_block_job(device, &aio_context, errp);
if (!job) {
return;
}
block_job_set_speed(job, speed, errp);
aio_context_release(aio_context);
}
void qmp_block_job_cancel(const char *device,
bool has_force, bool force, Error **errp)
{
AioContext *aio_context;
BlockJob *job = find_block_job(device, &aio_context, errp);
if (!job) {
return;
}
if (!has_force) {
force = false;
}
if (block_job_user_paused(job) && !force) {
error_setg(errp, "The block job for device '%s' is currently paused",
device);
goto out;
}
trace_qmp_block_job_cancel(job);
block_job_cancel(job);
out:
aio_context_release(aio_context);
}
void qmp_block_job_pause(const char *device, Error **errp)
{
AioContext *aio_context;
BlockJob *job = find_block_job(device, &aio_context, errp);
if (!job || block_job_user_paused(job)) {
return;
}
trace_qmp_block_job_pause(job);
block_job_user_pause(job);
aio_context_release(aio_context);
}
void qmp_block_job_resume(const char *device, Error **errp)
{
AioContext *aio_context;
BlockJob *job = find_block_job(device, &aio_context, errp);
if (!job || !block_job_user_paused(job)) {
return;
}
trace_qmp_block_job_resume(job);
block_job_user_resume(job);
aio_context_release(aio_context);
}
void qmp_block_job_complete(const char *device, Error **errp)
{
AioContext *aio_context;
BlockJob *job = find_block_job(device, &aio_context, errp);
if (!job) {
return;
}
trace_qmp_block_job_complete(job);
block_job_complete(job, errp);
aio_context_release(aio_context);
}
void qmp_change_backing_file(const char *device,
const char *image_node_name,
const char *backing_file,
Error **errp)
{
BlockDriverState *bs = NULL;
AioContext *aio_context;
BlockDriverState *image_bs = NULL;
Error *local_err = NULL;
bool ro;
int open_flags;
int ret;
bs = qmp_get_root_bs(device, errp);
if (!bs) {
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
image_bs = bdrv_lookup_bs(NULL, image_node_name, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out;
}
if (!image_bs) {
error_setg(errp, "image file not found");
goto out;
}
if (bdrv_find_base(image_bs) == image_bs) {
error_setg(errp, "not allowing backing file change on an image "
"without a backing file");
goto out;
}
/* even though we are not necessarily operating on bs, we need it to
* determine if block ops are currently prohibited on the chain */
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
goto out;
}
/* final sanity check */
if (!bdrv_chain_contains(bs, image_bs)) {
error_setg(errp, "'%s' and image file are not in the same chain",
device);
goto out;
}
/* if not r/w, reopen to make r/w */
open_flags = image_bs->open_flags;
ro = bdrv_is_read_only(image_bs);
if (ro) {
bdrv_reopen(image_bs, open_flags | BDRV_O_RDWR, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out;
}
}
ret = bdrv_change_backing_file(image_bs, backing_file,
image_bs->drv ? image_bs->drv->format_name : "");
if (ret < 0) {
error_setg_errno(errp, -ret, "Could not change backing file to '%s'",
backing_file);
/* don't exit here, so we can try to restore open flags if
* appropriate */
}
if (ro) {
bdrv_reopen(image_bs, open_flags, &local_err);
error_propagate(errp, local_err);
}
out:
aio_context_release(aio_context);
}
void hmp_drive_add_node(Monitor *mon, const char *optstr)
{
QemuOpts *opts;
QDict *qdict;
Error *local_err = NULL;
opts = qemu_opts_parse_noisily(&qemu_drive_opts, optstr, false);
if (!opts) {
return;
}
qdict = qemu_opts_to_qdict(opts, NULL);
if (!qdict_get_try_str(qdict, "node-name")) {
QDECREF(qdict);
error_report("'node-name' needs to be specified");
goto out;
}
BlockDriverState *bs = bds_tree_init(qdict, &local_err);
if (!bs) {
error_report_err(local_err);
goto out;
}
QTAILQ_INSERT_TAIL(&monitor_bdrv_states, bs, monitor_list);
out:
qemu_opts_del(opts);
}
void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
{
BlockDriverState *bs;
QObject *obj;
Visitor *v = qobject_output_visitor_new(&obj);
QDict *qdict;
Error *local_err = NULL;
qapi: Add new visit_complete() function Making each output visitor provide its own output collection function was the only remaining reason for exposing visitor sub-types to the rest of the code base. Add a polymorphic visit_complete() function which is a no-op for input visitors, and which populates an opaque pointer for output visitors. For maximum type-safety, also add a parameter to the output visitor constructors with a type-correct version of the output pointer, and assert that the two uses match. This approach was considered superior to either passing the output parameter only during construction (action at a distance during visit_free() feels awkward) or only during visit_complete() (defeating type safety makes it easier to use incorrectly). Most callers were function-local, and therefore a mechanical conversion; the testsuite was a bit trickier, but the previous cleanup patch minimized the churn here. The visit_complete() function may be called at most once; doing so lets us use transfer semantics rather than duplication or ref-count semantics to get the just-built output back to the caller, even though it means our behavior is not idempotent. Generated code is simplified as follows for events: |@@ -26,7 +26,7 @@ void qapi_event_send_acpi_device_ost(ACP | QDict *qmp; | Error *err = NULL; | QMPEventFuncEmit emit; |- QmpOutputVisitor *qov; |+ QObject *obj; | Visitor *v; | q_obj_ACPI_DEVICE_OST_arg param = { | info |@@ -39,8 +39,7 @@ void qapi_event_send_acpi_device_ost(ACP | | qmp = qmp_event_build_dict("ACPI_DEVICE_OST"); | |- qov = qmp_output_visitor_new(); |- v = qmp_output_get_visitor(qov); |+ v = qmp_output_visitor_new(&obj); | | visit_start_struct(v, "ACPI_DEVICE_OST", NULL, 0, &err); | if (err) { |@@ -55,7 +54,8 @@ void qapi_event_send_acpi_device_ost(ACP | goto out; | } | |- qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov)); |+ visit_complete(v, &obj); |+ qdict_put_obj(qmp, "data", obj); | emit(QAPI_EVENT_ACPI_DEVICE_OST, qmp, &err); and for commands: | { | Error *err = NULL; |- QmpOutputVisitor *qov = qmp_output_visitor_new(); | Visitor *v; | |- v = qmp_output_get_visitor(qov); |+ v = qmp_output_visitor_new(ret_out); | visit_type_AddfdInfo(v, "unused", &ret_in, &err); |- if (err) { |- goto out; |+ if (!err) { |+ visit_complete(v, ret_out); | } |- *ret_out = qmp_output_get_qobject(qov); |- |-out: | error_propagate(errp, err); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1465490926-28625-13-git-send-email-eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-06-09 18:48:43 +02:00
visit_type_BlockdevOptions(v, NULL, &options, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto fail;
}
qapi: Add new visit_complete() function Making each output visitor provide its own output collection function was the only remaining reason for exposing visitor sub-types to the rest of the code base. Add a polymorphic visit_complete() function which is a no-op for input visitors, and which populates an opaque pointer for output visitors. For maximum type-safety, also add a parameter to the output visitor constructors with a type-correct version of the output pointer, and assert that the two uses match. This approach was considered superior to either passing the output parameter only during construction (action at a distance during visit_free() feels awkward) or only during visit_complete() (defeating type safety makes it easier to use incorrectly). Most callers were function-local, and therefore a mechanical conversion; the testsuite was a bit trickier, but the previous cleanup patch minimized the churn here. The visit_complete() function may be called at most once; doing so lets us use transfer semantics rather than duplication or ref-count semantics to get the just-built output back to the caller, even though it means our behavior is not idempotent. Generated code is simplified as follows for events: |@@ -26,7 +26,7 @@ void qapi_event_send_acpi_device_ost(ACP | QDict *qmp; | Error *err = NULL; | QMPEventFuncEmit emit; |- QmpOutputVisitor *qov; |+ QObject *obj; | Visitor *v; | q_obj_ACPI_DEVICE_OST_arg param = { | info |@@ -39,8 +39,7 @@ void qapi_event_send_acpi_device_ost(ACP | | qmp = qmp_event_build_dict("ACPI_DEVICE_OST"); | |- qov = qmp_output_visitor_new(); |- v = qmp_output_get_visitor(qov); |+ v = qmp_output_visitor_new(&obj); | | visit_start_struct(v, "ACPI_DEVICE_OST", NULL, 0, &err); | if (err) { |@@ -55,7 +54,8 @@ void qapi_event_send_acpi_device_ost(ACP | goto out; | } | |- qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov)); |+ visit_complete(v, &obj); |+ qdict_put_obj(qmp, "data", obj); | emit(QAPI_EVENT_ACPI_DEVICE_OST, qmp, &err); and for commands: | { | Error *err = NULL; |- QmpOutputVisitor *qov = qmp_output_visitor_new(); | Visitor *v; | |- v = qmp_output_get_visitor(qov); |+ v = qmp_output_visitor_new(ret_out); | visit_type_AddfdInfo(v, "unused", &ret_in, &err); |- if (err) { |- goto out; |+ if (!err) { |+ visit_complete(v, ret_out); | } |- *ret_out = qmp_output_get_qobject(qov); |- |-out: | error_propagate(errp, err); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1465490926-28625-13-git-send-email-eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-06-09 18:48:43 +02:00
visit_complete(v, &obj);
qdict = qobject_to_qdict(obj);
qdict_flatten(qdict);
if (!qdict_get_try_str(qdict, "node-name")) {
error_setg(errp, "'node-name' must be specified for the root node");
goto fail;
}
bs = bds_tree_init(qdict, errp);
if (!bs) {
goto fail;
}
QTAILQ_INSERT_TAIL(&monitor_bdrv_states, bs, monitor_list);
if (bs && bdrv_key_required(bs)) {
QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
bdrv_unref(bs);
error_setg(errp, "blockdev-add doesn't support encrypted devices");
goto fail;
}
fail:
qapi: Add new visit_complete() function Making each output visitor provide its own output collection function was the only remaining reason for exposing visitor sub-types to the rest of the code base. Add a polymorphic visit_complete() function which is a no-op for input visitors, and which populates an opaque pointer for output visitors. For maximum type-safety, also add a parameter to the output visitor constructors with a type-correct version of the output pointer, and assert that the two uses match. This approach was considered superior to either passing the output parameter only during construction (action at a distance during visit_free() feels awkward) or only during visit_complete() (defeating type safety makes it easier to use incorrectly). Most callers were function-local, and therefore a mechanical conversion; the testsuite was a bit trickier, but the previous cleanup patch minimized the churn here. The visit_complete() function may be called at most once; doing so lets us use transfer semantics rather than duplication or ref-count semantics to get the just-built output back to the caller, even though it means our behavior is not idempotent. Generated code is simplified as follows for events: |@@ -26,7 +26,7 @@ void qapi_event_send_acpi_device_ost(ACP | QDict *qmp; | Error *err = NULL; | QMPEventFuncEmit emit; |- QmpOutputVisitor *qov; |+ QObject *obj; | Visitor *v; | q_obj_ACPI_DEVICE_OST_arg param = { | info |@@ -39,8 +39,7 @@ void qapi_event_send_acpi_device_ost(ACP | | qmp = qmp_event_build_dict("ACPI_DEVICE_OST"); | |- qov = qmp_output_visitor_new(); |- v = qmp_output_get_visitor(qov); |+ v = qmp_output_visitor_new(&obj); | | visit_start_struct(v, "ACPI_DEVICE_OST", NULL, 0, &err); | if (err) { |@@ -55,7 +54,8 @@ void qapi_event_send_acpi_device_ost(ACP | goto out; | } | |- qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov)); |+ visit_complete(v, &obj); |+ qdict_put_obj(qmp, "data", obj); | emit(QAPI_EVENT_ACPI_DEVICE_OST, qmp, &err); and for commands: | { | Error *err = NULL; |- QmpOutputVisitor *qov = qmp_output_visitor_new(); | Visitor *v; | |- v = qmp_output_get_visitor(qov); |+ v = qmp_output_visitor_new(ret_out); | visit_type_AddfdInfo(v, "unused", &ret_in, &err); |- if (err) { |- goto out; |+ if (!err) { |+ visit_complete(v, ret_out); | } |- *ret_out = qmp_output_get_qobject(qov); |- |-out: | error_propagate(errp, err); Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1465490926-28625-13-git-send-email-eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-06-09 18:48:43 +02:00
visit_free(v);
}
void qmp_blockdev_del(const char *node_name, Error **errp)
{
AioContext *aio_context;
BlockDriverState *bs;
bs = bdrv_find_node(node_name);
if (!bs) {
error_setg(errp, "Cannot find node %s", node_name);
return;
}
if (bdrv_has_blk(bs)) {
error_setg(errp, "Node %s is in use", node_name);
return;
}
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, errp)) {
goto out;
}
if (!bs->monitor_list.tqe_prev) {
error_setg(errp, "Node %s is not owned by the monitor",
bs->node_name);
goto out;
}
if (bs->refcnt > 1) {
error_setg(errp, "Block device %s is in use",
bdrv_get_device_or_node_name(bs));
goto out;
}
QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
bdrv_unref(bs);
out:
aio_context_release(aio_context);
}
static BdrvChild *bdrv_find_child(BlockDriverState *parent_bs,
const char *child_name)
{
BdrvChild *child;
QLIST_FOREACH(child, &parent_bs->children, next) {
if (strcmp(child->name, child_name) == 0) {
return child;
}
}
return NULL;
}
void qmp_x_blockdev_change(const char *parent, bool has_child,
const char *child, bool has_node,
const char *node, Error **errp)
{
BlockDriverState *parent_bs, *new_bs = NULL;
BdrvChild *p_child;
parent_bs = bdrv_lookup_bs(parent, parent, errp);
if (!parent_bs) {
return;
}
if (has_child == has_node) {
if (has_child) {
error_setg(errp, "The parameters child and node are in conflict");
} else {
error_setg(errp, "Either child or node must be specified");
}
return;
}
if (has_child) {
p_child = bdrv_find_child(parent_bs, child);
if (!p_child) {
error_setg(errp, "Node '%s' does not have child '%s'",
parent, child);
return;
}
bdrv_del_child(parent_bs, p_child, errp);
}
if (has_node) {
new_bs = bdrv_find_node(node);
if (!new_bs) {
error_setg(errp, "Node '%s' not found", node);
return;
}
bdrv_add_child(parent_bs, new_bs, errp);
}
}
BlockJobInfoList *qmp_query_block_jobs(Error **errp)
{
BlockJobInfoList *head = NULL, **p_next = &head;
BlockJob *job;
for (job = block_job_next(NULL); job; job = block_job_next(job)) {
BlockJobInfoList *elem;
AioContext *aio_context;
if (block_job_is_internal(job)) {
continue;
}
elem = g_new0(BlockJobInfoList, 1);
aio_context = blk_get_aio_context(job->blk);
aio_context_acquire(aio_context);
elem->value = block_job_query(job, errp);
aio_context_release(aio_context);
if (!elem->value) {
g_free(elem);
qapi_free_BlockJobInfoList(head);
return NULL;
}
*p_next = elem;
p_next = &elem->next;
}
return head;
}
QemuOptsList qemu_common_drive_opts = {
.name = "drive",
.head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),
.desc = {
{
.name = "snapshot",
.type = QEMU_OPT_BOOL,
.help = "enable/disable snapshot mode",
},{
.name = "aio",
.type = QEMU_OPT_STRING,
.help = "host AIO implementation (threads, native)",
},{
.name = BDRV_OPT_CACHE_WB,
.type = QEMU_OPT_BOOL,
.help = "Enable writeback mode",
},{
.name = "format",
.type = QEMU_OPT_STRING,
.help = "disk format (raw, qcow2, ...)",
},{
.name = "rerror",
.type = QEMU_OPT_STRING,
.help = "read error action",
},{
.name = "werror",
.type = QEMU_OPT_STRING,
.help = "write error action",
},{
.name = BDRV_OPT_READ_ONLY,
.type = QEMU_OPT_BOOL,
.help = "open drive file as read-only",
},
THROTTLE_OPTS,
{
.name = "throttling.group",
.type = QEMU_OPT_STRING,
.help = "name of the block throttling group",
},{
.name = "copy-on-read",
.type = QEMU_OPT_BOOL,
.help = "copy read data from backing file into image file",
},{
.name = "detect-zeroes",
.type = QEMU_OPT_STRING,
.help = "try to optimize zero writes (off, on, unmap)",
},{
.name = "stats-account-invalid",
.type = QEMU_OPT_BOOL,
.help = "whether to account for invalid I/O operations "
"in the statistics",
},{
.name = "stats-account-failed",
.type = QEMU_OPT_BOOL,
.help = "whether to account for failed I/O operations "
"in the statistics",
},
{ /* end of list */ }
},
};
QemuOptsList qemu_drive_opts = {
.name = "drive",
.head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
.desc = {
/*
* no elements => accept any params
* validation will happen later
*/
{ /* end of list */ }
},
};