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qemu-e2k/blockdev.c
Jeff Cody 8802d1fdd4 qapi: Introduce blockdev-group-snapshot-sync command 
This is a QAPI/QMP only command to take a snapshot of a group of
devices. This is similar to the blockdev-snapshot-sync command, except
blockdev-group-snapshot-sync accepts a list devices, filenames, and
formats.

It is attempted to keep the snapshot of the group atomic; if the
creation or open of any of the new snapshots fails, then all of
the new snapshots are abandoned, and the name of the snapshot image
that failed is returned.  The failure case should not interrupt
any operations.

Rather than use bdrv_close() along with a subsequent bdrv_open() to
perform the pivot, the original image is never closed and the new
image is placed 'in front' of the original image via manipulation
of the BlockDriverState fields.  Thus, once the new snapshot image
has been successfully created, there are no more failure points
before pivoting to the new snapshot.

This allows the group of disks to remain consistent with each other,
even across snapshot failures.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Acked-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-02-29 15:48:33 +01:00

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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.
*/
#include "block.h"
#include "blockdev.h"
#include "monitor.h"
#include "qerror.h"
#include "qemu-option.h"
#include "qemu-config.h"
#include "qemu-objects.h"
#include "sysemu.h"
#include "block_int.h"
#include "qmp-commands.h"
#include "trace.h"
#include "arch_init.h"
static QTAILQ_HEAD(drivelist, DriveInfo) drives = QTAILQ_HEAD_INITIALIZER(drives);
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 const 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 imlement 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,
};
/*
* 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(BlockDriverState *bs)
{
DriveInfo *dinfo = drive_get_by_blockdev(bs);
if (dinfo) {
dinfo->auto_del = 1;
}
}
void blockdev_auto_del(BlockDriverState *bs)
{
DriveInfo *dinfo = drive_get_by_blockdev(bs);
if (dinfo && dinfo->auto_del) {
drive_put_ref(dinfo);
}
}
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)
{
return qemu_opts_parse(qemu_find_opts("drive"), optstr, 0);
}
QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
const char *optstr)
{
QemuOpts *opts;
char buf[32];
opts = drive_def(optstr);
if (!opts) {
return NULL;
}
if (type != IF_DEFAULT) {
qemu_opt_set(opts, "if", if_name[type]);
}
if (index >= 0) {
snprintf(buf, sizeof(buf), "%d", index);
qemu_opt_set(opts, "index", buf);
}
if (file)
qemu_opt_set(opts, "file", file);
return opts;
}
DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
{
DriveInfo *dinfo;
/* seek interface, bus and unit */
QTAILQ_FOREACH(dinfo, &drives, next) {
if (dinfo->type == type &&
dinfo->bus == bus &&
dinfo->unit == unit)
return dinfo;
}
return NULL;
}
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;
DriveInfo *dinfo;
max_bus = -1;
QTAILQ_FOREACH(dinfo, &drives, next) {
if(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]++);
}
DriveInfo *drive_get_by_blockdev(BlockDriverState *bs)
{
DriveInfo *dinfo;
QTAILQ_FOREACH(dinfo, &drives, next) {
if (dinfo->bdrv == bs) {
return dinfo;
}
}
return NULL;
}
static void bdrv_format_print(void *opaque, const char *name)
{
error_printf(" %s", name);
}
static void drive_uninit(DriveInfo *dinfo)
{
qemu_opts_del(dinfo->opts);
bdrv_delete(dinfo->bdrv);
g_free(dinfo->id);
QTAILQ_REMOVE(&drives, dinfo, next);
g_free(dinfo);
}
void drive_put_ref(DriveInfo *dinfo)
{
assert(dinfo->refcount);
if (--dinfo->refcount == 0) {
drive_uninit(dinfo);
}
}
void drive_get_ref(DriveInfo *dinfo)
{
dinfo->refcount++;
}
typedef struct {
QEMUBH *bh;
DriveInfo *dinfo;
} DrivePutRefBH;
static void drive_put_ref_bh(void *opaque)
{
DrivePutRefBH *s = opaque;
drive_put_ref(s->dinfo);
qemu_bh_delete(s->bh);
g_free(s);
}
/*
* Release a drive reference in a BH
*
* It is not possible to use drive_put_ref() from a callback function when the
* callers still need the drive. In such cases we schedule a BH to release the
* reference.
*/
static void drive_put_ref_bh_schedule(DriveInfo *dinfo)
{
DrivePutRefBH *s;
s = g_new(DrivePutRefBH, 1);
s->bh = qemu_bh_new(drive_put_ref_bh, s);
s->dinfo = dinfo;
qemu_bh_schedule(s->bh);
}
static int parse_block_error_action(const char *buf, int is_read)
{
if (!strcmp(buf, "ignore")) {
return BLOCK_ERR_IGNORE;
} else if (!is_read && !strcmp(buf, "enospc")) {
return BLOCK_ERR_STOP_ENOSPC;
} else if (!strcmp(buf, "stop")) {
return BLOCK_ERR_STOP_ANY;
} else if (!strcmp(buf, "report")) {
return BLOCK_ERR_REPORT;
} else {
error_report("'%s' invalid %s error action",
buf, is_read ? "read" : "write");
return -1;
}
}
static bool do_check_io_limits(BlockIOLimit *io_limits)
{
bool bps_flag;
bool iops_flag;
assert(io_limits);
bps_flag = (io_limits->bps[BLOCK_IO_LIMIT_TOTAL] != 0)
&& ((io_limits->bps[BLOCK_IO_LIMIT_READ] != 0)
|| (io_limits->bps[BLOCK_IO_LIMIT_WRITE] != 0));
iops_flag = (io_limits->iops[BLOCK_IO_LIMIT_TOTAL] != 0)
&& ((io_limits->iops[BLOCK_IO_LIMIT_READ] != 0)
|| (io_limits->iops[BLOCK_IO_LIMIT_WRITE] != 0));
if (bps_flag || iops_flag) {
return false;
}
return true;
}
DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi)
{
const char *buf;
const char *file = NULL;
char devname[128];
const char *serial;
const char *mediastr = "";
BlockInterfaceType type;
enum { MEDIA_DISK, MEDIA_CDROM } media;
int bus_id, unit_id;
int cyls, heads, secs, translation;
BlockDriver *drv = NULL;
int max_devs;
int index;
int ro = 0;
int bdrv_flags = 0;
int on_read_error, on_write_error;
const char *devaddr;
DriveInfo *dinfo;
BlockIOLimit io_limits;
int snapshot = 0;
bool copy_on_read;
int ret;
translation = BIOS_ATA_TRANSLATION_AUTO;
media = MEDIA_DISK;
/* extract parameters */
bus_id = qemu_opt_get_number(opts, "bus", 0);
unit_id = qemu_opt_get_number(opts, "unit", -1);
index = qemu_opt_get_number(opts, "index", -1);
cyls = qemu_opt_get_number(opts, "cyls", 0);
heads = qemu_opt_get_number(opts, "heads", 0);
secs = qemu_opt_get_number(opts, "secs", 0);
snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
ro = qemu_opt_get_bool(opts, "readonly", 0);
copy_on_read = qemu_opt_get_bool(opts, "copy-on-read", false);
file = qemu_opt_get(opts, "file");
serial = qemu_opt_get(opts, "serial");
if ((buf = qemu_opt_get(opts, "if")) != NULL) {
pstrcpy(devname, sizeof(devname), buf);
for (type = 0; type < IF_COUNT && strcmp(buf, if_name[type]); type++)
;
if (type == IF_COUNT) {
error_report("unsupported bus type '%s'", buf);
return NULL;
}
} else {
type = default_to_scsi ? IF_SCSI : IF_IDE;
pstrcpy(devname, sizeof(devname), if_name[type]);
}
max_devs = if_max_devs[type];
if (cyls || heads || secs) {
if (cyls < 1 || (type == IF_IDE && cyls > 16383)) {
error_report("invalid physical cyls number");
return NULL;
}
if (heads < 1 || (type == IF_IDE && heads > 16)) {
error_report("invalid physical heads number");
return NULL;
}
if (secs < 1 || (type == IF_IDE && secs > 63)) {
error_report("invalid physical secs number");
return NULL;
}
}
if ((buf = qemu_opt_get(opts, "trans")) != NULL) {
if (!cyls) {
error_report("'%s' trans must be used with cyls, heads and secs",
buf);
return NULL;
}
if (!strcmp(buf, "none"))
translation = BIOS_ATA_TRANSLATION_NONE;
else if (!strcmp(buf, "lba"))
translation = BIOS_ATA_TRANSLATION_LBA;
else if (!strcmp(buf, "auto"))
translation = BIOS_ATA_TRANSLATION_AUTO;
else {
error_report("'%s' invalid translation type", buf);
return NULL;
}
}
if ((buf = qemu_opt_get(opts, "media")) != NULL) {
if (!strcmp(buf, "disk")) {
media = MEDIA_DISK;
} else if (!strcmp(buf, "cdrom")) {
if (cyls || secs || heads) {
error_report("CHS can't be set with media=%s", buf);
return NULL;
}
media = MEDIA_CDROM;
} else {
error_report("'%s' invalid media", buf);
return NULL;
}
}
if ((buf = qemu_opt_get(opts, "cache")) != NULL) {
if (bdrv_parse_cache_flags(buf, &bdrv_flags) != 0) {
error_report("invalid cache option");
return NULL;
}
}
#ifdef CONFIG_LINUX_AIO
if ((buf = qemu_opt_get(opts, "aio")) != NULL) {
if (!strcmp(buf, "native")) {
bdrv_flags |= BDRV_O_NATIVE_AIO;
} else if (!strcmp(buf, "threads")) {
/* this is the default */
} else {
error_report("invalid aio option");
return NULL;
}
}
#endif
if ((buf = qemu_opt_get(opts, "format")) != NULL) {
if (strcmp(buf, "?") == 0) {
error_printf("Supported formats:");
bdrv_iterate_format(bdrv_format_print, NULL);
error_printf("\n");
return NULL;
}
drv = bdrv_find_whitelisted_format(buf);
if (!drv) {
error_report("'%s' invalid format", buf);
return NULL;
}
}
/* disk I/O throttling */
io_limits.bps[BLOCK_IO_LIMIT_TOTAL] =
qemu_opt_get_number(opts, "bps", 0);
io_limits.bps[BLOCK_IO_LIMIT_READ] =
qemu_opt_get_number(opts, "bps_rd", 0);
io_limits.bps[BLOCK_IO_LIMIT_WRITE] =
qemu_opt_get_number(opts, "bps_wr", 0);
io_limits.iops[BLOCK_IO_LIMIT_TOTAL] =
qemu_opt_get_number(opts, "iops", 0);
io_limits.iops[BLOCK_IO_LIMIT_READ] =
qemu_opt_get_number(opts, "iops_rd", 0);
io_limits.iops[BLOCK_IO_LIMIT_WRITE] =
qemu_opt_get_number(opts, "iops_wr", 0);
if (!do_check_io_limits(&io_limits)) {
error_report("bps(iops) and bps_rd/bps_wr(iops_rd/iops_wr) "
"cannot be used at the same time");
return NULL;
}
on_write_error = BLOCK_ERR_STOP_ENOSPC;
if ((buf = qemu_opt_get(opts, "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");
return NULL;
}
on_write_error = parse_block_error_action(buf, 0);
if (on_write_error < 0) {
return NULL;
}
}
on_read_error = BLOCK_ERR_REPORT;
if ((buf = qemu_opt_get(opts, "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");
return NULL;
}
on_read_error = parse_block_error_action(buf, 1);
if (on_read_error < 0) {
return NULL;
}
}
if ((devaddr = qemu_opt_get(opts, "addr")) != NULL) {
if (type != IF_VIRTIO) {
error_report("addr is not supported by this bus type");
return NULL;
}
}
/* compute bus and unit according index */
if (index != -1) {
if (bus_id != 0 || unit_id != -1) {
error_report("index cannot be used with bus and unit");
return NULL;
}
bus_id = drive_index_to_bus_id(type, index);
unit_id = drive_index_to_unit_id(type, index);
}
/* if user doesn't specify a unit_id,
* try to find the first free
*/
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++;
}
}
}
/* check unit id */
if (max_devs && unit_id >= max_devs) {
error_report("unit %d too big (max is %d)",
unit_id, max_devs - 1);
return NULL;
}
/*
* catch multiple definitions
*/
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);
return NULL;
}
/* init */
dinfo = g_malloc0(sizeof(*dinfo));
if ((buf = qemu_opts_id(opts)) != NULL) {
dinfo->id = g_strdup(buf);
} else {
/* no id supplied -> create one */
dinfo->id = g_malloc0(32);
if (type == IF_IDE || type == IF_SCSI)
mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
if (max_devs)
snprintf(dinfo->id, 32, "%s%i%s%i",
devname, bus_id, mediastr, unit_id);
else
snprintf(dinfo->id, 32, "%s%s%i",
devname, mediastr, unit_id);
}
dinfo->bdrv = bdrv_new(dinfo->id);
dinfo->devaddr = devaddr;
dinfo->type = type;
dinfo->bus = bus_id;
dinfo->unit = unit_id;
dinfo->opts = opts;
dinfo->refcount = 1;
if (serial)
strncpy(dinfo->serial, serial, sizeof(dinfo->serial) - 1);
QTAILQ_INSERT_TAIL(&drives, dinfo, next);
bdrv_set_on_error(dinfo->bdrv, on_read_error, on_write_error);
/* disk I/O throttling */
bdrv_set_io_limits(dinfo->bdrv, &io_limits);
switch(type) {
case IF_IDE:
case IF_SCSI:
case IF_XEN:
case IF_NONE:
switch(media) {
case MEDIA_DISK:
if (cyls != 0) {
bdrv_set_geometry_hint(dinfo->bdrv, cyls, heads, secs);
bdrv_set_translation_hint(dinfo->bdrv, translation);
}
break;
case MEDIA_CDROM:
dinfo->media_cd = 1;
break;
}
break;
case IF_SD:
case IF_FLOPPY:
case IF_PFLASH:
case IF_MTD:
break;
case IF_VIRTIO:
/* add virtio block device */
opts = qemu_opts_create(qemu_find_opts("device"), NULL, 0);
if (arch_type == QEMU_ARCH_S390X) {
qemu_opt_set(opts, "driver", "virtio-blk-s390");
} else {
qemu_opt_set(opts, "driver", "virtio-blk-pci");
}
qemu_opt_set(opts, "drive", dinfo->id);
if (devaddr)
qemu_opt_set(opts, "addr", devaddr);
break;
default:
abort();
}
if (!file || !*file) {
return dinfo;
}
if (snapshot) {
/* always use cache=unsafe with snapshot */
bdrv_flags &= ~BDRV_O_CACHE_MASK;
bdrv_flags |= (BDRV_O_SNAPSHOT|BDRV_O_CACHE_WB|BDRV_O_NO_FLUSH);
}
if (copy_on_read) {
bdrv_flags |= BDRV_O_COPY_ON_READ;
}
if (media == MEDIA_CDROM) {
/* CDROM is fine for any interface, don't check. */
ro = 1;
} else if (ro == 1) {
if (type != IF_SCSI && type != IF_VIRTIO && type != IF_FLOPPY &&
type != IF_NONE && type != IF_PFLASH) {
error_report("readonly not supported by this bus type");
goto err;
}
}
bdrv_flags |= ro ? 0 : BDRV_O_RDWR;
ret = bdrv_open(dinfo->bdrv, file, bdrv_flags, drv);
if (ret < 0) {
error_report("could not open disk image %s: %s",
file, strerror(-ret));
goto err;
}
if (bdrv_key_required(dinfo->bdrv))
autostart = 0;
return dinfo;
err:
bdrv_delete(dinfo->bdrv);
g_free(dinfo->id);
QTAILQ_REMOVE(&drives, dinfo, next);
g_free(dinfo);
return NULL;
}
void do_commit(Monitor *mon, const QDict *qdict)
{
const char *device = qdict_get_str(qdict, "device");
BlockDriverState *bs;
if (!strcmp(device, "all")) {
bdrv_commit_all();
} else {
int ret;
bs = bdrv_find(device);
if (!bs) {
qerror_report(QERR_DEVICE_NOT_FOUND, device);
return;
}
ret = bdrv_commit(bs);
if (ret == -EBUSY) {
qerror_report(QERR_DEVICE_IN_USE, device);
return;
}
}
}
void qmp_blockdev_snapshot_sync(const char *device, const char *snapshot_file,
bool has_format, const char *format,
Error **errp)
{
BlockDriverState *bs;
BlockDriver *drv, *old_drv, *proto_drv;
int ret = 0;
int flags;
char old_filename[1024];
bs = bdrv_find(device);
if (!bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, device);
return;
}
if (bdrv_in_use(bs)) {
error_set(errp, QERR_DEVICE_IN_USE, device);
return;
}
pstrcpy(old_filename, sizeof(old_filename), bs->filename);
old_drv = bs->drv;
flags = bs->open_flags;
if (!has_format) {
format = "qcow2";
}
drv = bdrv_find_format(format);
if (!drv) {
error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
return;
}
proto_drv = bdrv_find_protocol(snapshot_file);
if (!proto_drv) {
error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
return;
}
ret = bdrv_img_create(snapshot_file, format, bs->filename,
bs->drv->format_name, NULL, -1, flags);
if (ret) {
error_set(errp, QERR_UNDEFINED_ERROR);
return;
}
bdrv_drain_all();
bdrv_flush(bs);
bdrv_close(bs);
ret = bdrv_open(bs, snapshot_file, flags, drv);
/*
* If reopening the image file we just created fails, fall back
* and try to re-open the original image. If that fails too, we
* are in serious trouble.
*/
if (ret != 0) {
ret = bdrv_open(bs, old_filename, flags, old_drv);
if (ret != 0) {
error_set(errp, QERR_OPEN_FILE_FAILED, old_filename);
} else {
error_set(errp, QERR_OPEN_FILE_FAILED, snapshot_file);
}
}
}
/* New and old BlockDriverState structs for group snapshots */
typedef struct BlkGroupSnapshotStates {
BlockDriverState *old_bs;
BlockDriverState *new_bs;
QSIMPLEQ_ENTRY(BlkGroupSnapshotStates) entry;
} BlkGroupSnapshotStates;
/*
* 'Atomic' group snapshots. The snapshots are taken as a set, and if any fail
* then we do not pivot any of the devices in the group, and abandon the
* snapshots
*/
void qmp_blockdev_group_snapshot_sync(SnapshotDevList *dev_list,
Error **errp)
{
int ret = 0;
SnapshotDevList *dev_entry = dev_list;
SnapshotDev *dev_info = NULL;
BlkGroupSnapshotStates *states;
BlockDriver *proto_drv;
BlockDriver *drv;
int flags;
const char *format;
const char *snapshot_file;
QSIMPLEQ_HEAD(snap_bdrv_states, BlkGroupSnapshotStates) snap_bdrv_states;
QSIMPLEQ_INIT(&snap_bdrv_states);
/* drain all i/o before any snapshots */
bdrv_drain_all();
/* We don't do anything in this loop that commits us to the snapshot */
while (NULL != dev_entry) {
dev_info = dev_entry->value;
dev_entry = dev_entry->next;
states = g_malloc0(sizeof(BlkGroupSnapshotStates));
QSIMPLEQ_INSERT_TAIL(&snap_bdrv_states, states, entry);
states->old_bs = bdrv_find(dev_info->device);
if (!states->old_bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, dev_info->device);
goto delete_and_fail;
}
if (bdrv_in_use(states->old_bs)) {
error_set(errp, QERR_DEVICE_IN_USE, dev_info->device);
goto delete_and_fail;
}
if (!bdrv_is_read_only(states->old_bs) &&
bdrv_is_inserted(states->old_bs)) {
if (bdrv_flush(states->old_bs)) {
error_set(errp, QERR_IO_ERROR);
goto delete_and_fail;
}
}
snapshot_file = dev_info->snapshot_file;
flags = states->old_bs->open_flags;
if (!dev_info->has_format) {
format = "qcow2";
} else {
format = dev_info->format;
}
drv = bdrv_find_format(format);
if (!drv) {
error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
goto delete_and_fail;
}
proto_drv = bdrv_find_protocol(snapshot_file);
if (!proto_drv) {
error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
goto delete_and_fail;
}
/* create new image w/backing file */
ret = bdrv_img_create(snapshot_file, format,
states->old_bs->filename,
drv->format_name, NULL, -1, flags);
if (ret) {
error_set(errp, QERR_OPEN_FILE_FAILED, snapshot_file);
goto delete_and_fail;
}
/* We will manually add the backing_hd field to the bs later */
states->new_bs = bdrv_new("");
ret = bdrv_open(states->new_bs, snapshot_file,
flags | BDRV_O_NO_BACKING, drv);
if (ret != 0) {
error_set(errp, QERR_OPEN_FILE_FAILED, snapshot_file);
goto delete_and_fail;
}
}
/* Now we are going to do the actual pivot. Everything up to this point
* is reversible, but we are committed at this point */
QSIMPLEQ_FOREACH(states, &snap_bdrv_states, entry) {
/* This removes our old bs from the bdrv_states, and adds the new bs */
bdrv_append(states->new_bs, states->old_bs);
}
/* success */
goto exit;
delete_and_fail:
/*
* failure, and it is all-or-none; abandon each new bs, and keep using
* the original bs for all images
*/
QSIMPLEQ_FOREACH(states, &snap_bdrv_states, entry) {
if (states->new_bs) {
bdrv_delete(states->new_bs);
}
}
exit:
QSIMPLEQ_FOREACH(states, &snap_bdrv_states, entry) {
g_free(states);
}
return;
}
static void eject_device(BlockDriverState *bs, int force, Error **errp)
{
if (bdrv_in_use(bs)) {
error_set(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs));
return;
}
if (!bdrv_dev_has_removable_media(bs)) {
error_set(errp, QERR_DEVICE_NOT_REMOVABLE, bdrv_get_device_name(bs));
return;
}
if (bdrv_dev_is_medium_locked(bs) && !bdrv_dev_is_tray_open(bs)) {
bdrv_dev_eject_request(bs, force);
if (!force) {
error_set(errp, QERR_DEVICE_LOCKED, bdrv_get_device_name(bs));
return;
}
}
bdrv_close(bs);
}
void qmp_eject(const char *device, bool has_force, bool force, Error **errp)
{
BlockDriverState *bs;
bs = bdrv_find(device);
if (!bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, device);
return;
}
eject_device(bs, force, errp);
}
void qmp_block_passwd(const char *device, const char *password, Error **errp)
{
BlockDriverState *bs;
int err;
bs = bdrv_find(device);
if (!bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, device);
return;
}
err = bdrv_set_key(bs, password);
if (err == -EINVAL) {
error_set(errp, QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
return;
} else if (err < 0) {
error_set(errp, QERR_INVALID_PASSWORD);
return;
}
}
static void qmp_bdrv_open_encrypted(BlockDriverState *bs, const char *filename,
int bdrv_flags, BlockDriver *drv,
const char *password, Error **errp)
{
if (bdrv_open(bs, filename, bdrv_flags, drv) < 0) {
error_set(errp, QERR_OPEN_FILE_FAILED, filename);
return;
}
if (bdrv_key_required(bs)) {
if (password) {
if (bdrv_set_key(bs, password) < 0) {
error_set(errp, QERR_INVALID_PASSWORD);
}
} else {
error_set(errp, QERR_DEVICE_ENCRYPTED, bdrv_get_device_name(bs),
bdrv_get_encrypted_filename(bs));
}
} else if (password) {
error_set(errp, QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs));
}
}
void qmp_change_blockdev(const char *device, const char *filename,
bool has_format, const char *format, Error **errp)
{
BlockDriverState *bs;
BlockDriver *drv = NULL;
int bdrv_flags;
Error *err = NULL;
bs = bdrv_find(device);
if (!bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, device);
return;
}
if (format) {
drv = bdrv_find_whitelisted_format(format);
if (!drv) {
error_set(errp, QERR_INVALID_BLOCK_FORMAT, format);
return;
}
}
eject_device(bs, 0, &err);
if (error_is_set(&err)) {
error_propagate(errp, err);
return;
}
bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR;
bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0;
qmp_bdrv_open_encrypted(bs, filename, bdrv_flags, drv, NULL, errp);
}
/* throttling disk I/O limits */
void qmp_block_set_io_throttle(const char *device, int64_t bps, int64_t bps_rd,
int64_t bps_wr, int64_t iops, int64_t iops_rd,
int64_t iops_wr, Error **errp)
{
BlockIOLimit io_limits;
BlockDriverState *bs;
bs = bdrv_find(device);
if (!bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, device);
return;
}
io_limits.bps[BLOCK_IO_LIMIT_TOTAL] = bps;
io_limits.bps[BLOCK_IO_LIMIT_READ] = bps_rd;
io_limits.bps[BLOCK_IO_LIMIT_WRITE] = bps_wr;
io_limits.iops[BLOCK_IO_LIMIT_TOTAL]= iops;
io_limits.iops[BLOCK_IO_LIMIT_READ] = iops_rd;
io_limits.iops[BLOCK_IO_LIMIT_WRITE]= iops_wr;
if (!do_check_io_limits(&io_limits)) {
error_set(errp, QERR_INVALID_PARAMETER_COMBINATION);
return;
}
bs->io_limits = io_limits;
bs->slice_time = BLOCK_IO_SLICE_TIME;
if (!bs->io_limits_enabled && bdrv_io_limits_enabled(bs)) {
bdrv_io_limits_enable(bs);
} else if (bs->io_limits_enabled && !bdrv_io_limits_enabled(bs)) {
bdrv_io_limits_disable(bs);
} else {
if (bs->block_timer) {
qemu_mod_timer(bs->block_timer, qemu_get_clock_ns(vm_clock));
}
}
}
int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data)
{
const char *id = qdict_get_str(qdict, "id");
BlockDriverState *bs;
bs = bdrv_find(id);
if (!bs) {
qerror_report(QERR_DEVICE_NOT_FOUND, id);
return -1;
}
if (bdrv_in_use(bs)) {
qerror_report(QERR_DEVICE_IN_USE, id);
return -1;
}
/* quiesce block driver; prevent further io */
bdrv_drain_all();
bdrv_flush(bs);
bdrv_close(bs);
/* if we have a device attached to this BlockDriverState
* then we need to make the drive anonymous until the device
* can be removed. If this is a drive with no device backing
* then we can just get rid of the block driver state right here.
*/
if (bdrv_get_attached_dev(bs)) {
bdrv_make_anon(bs);
} else {
drive_uninit(drive_get_by_blockdev(bs));
}
return 0;
}
void qmp_block_resize(const char *device, int64_t size, Error **errp)
{
BlockDriverState *bs;
bs = bdrv_find(device);
if (!bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, device);
return;
}
if (size < 0) {
error_set(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
return;
}
switch (bdrv_truncate(bs, size)) {
case 0:
break;
case -ENOMEDIUM:
error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
break;
case -ENOTSUP:
error_set(errp, QERR_UNSUPPORTED);
break;
case -EACCES:
error_set(errp, QERR_DEVICE_IS_READ_ONLY, device);
break;
case -EBUSY:
error_set(errp, QERR_DEVICE_IN_USE, device);
break;
default:
error_set(errp, QERR_UNDEFINED_ERROR);
break;
}
}
static QObject *qobject_from_block_job(BlockJob *job)
{
return qobject_from_jsonf("{ 'type': %s,"
"'device': %s,"
"'len': %" PRId64 ","
"'offset': %" PRId64 ","
"'speed': %" PRId64 " }",
job->job_type->job_type,
bdrv_get_device_name(job->bs),
job->len,
job->offset,
job->speed);
}
static void block_stream_cb(void *opaque, int ret)
{
BlockDriverState *bs = opaque;
QObject *obj;
trace_block_stream_cb(bs, bs->job, ret);
assert(bs->job);
obj = qobject_from_block_job(bs->job);
if (ret < 0) {
QDict *dict = qobject_to_qdict(obj);
qdict_put(dict, "error", qstring_from_str(strerror(-ret)));
}
if (block_job_is_cancelled(bs->job)) {
monitor_protocol_event(QEVENT_BLOCK_JOB_CANCELLED, obj);
} else {
monitor_protocol_event(QEVENT_BLOCK_JOB_COMPLETED, obj);
}
qobject_decref(obj);
drive_put_ref_bh_schedule(drive_get_by_blockdev(bs));
}
void qmp_block_stream(const char *device, bool has_base,
const char *base, Error **errp)
{
BlockDriverState *bs;
BlockDriverState *base_bs = NULL;
int ret;
bs = bdrv_find(device);
if (!bs) {
error_set(errp, QERR_DEVICE_NOT_FOUND, device);
return;
}
if (base) {
base_bs = bdrv_find_backing_image(bs, base);
if (base_bs == NULL) {
error_set(errp, QERR_BASE_NOT_FOUND, base);
return;
}
}
ret = stream_start(bs, base_bs, base, block_stream_cb, bs);
if (ret < 0) {
switch (ret) {
case -EBUSY:
error_set(errp, QERR_DEVICE_IN_USE, device);
return;
default:
error_set(errp, QERR_NOT_SUPPORTED);
return;
}
}
/* Grab a reference so hotplug does not delete the BlockDriverState from
* underneath us.
*/
drive_get_ref(drive_get_by_blockdev(bs));
trace_qmp_block_stream(bs, bs->job);
}
static BlockJob *find_block_job(const char *device)
{
BlockDriverState *bs;
bs = bdrv_find(device);
if (!bs || !bs->job) {
return NULL;
}
return bs->job;
}
void qmp_block_job_set_speed(const char *device, int64_t value, Error **errp)
{
BlockJob *job = find_block_job(device);
if (!job) {
error_set(errp, QERR_DEVICE_NOT_ACTIVE, device);
return;
}
if (block_job_set_speed(job, value) < 0) {
error_set(errp, QERR_NOT_SUPPORTED);
}
}
void qmp_block_job_cancel(const char *device, Error **errp)
{
BlockJob *job = find_block_job(device);
if (!job) {
error_set(errp, QERR_DEVICE_NOT_ACTIVE, device);
return;
}
trace_qmp_block_job_cancel(job);
block_job_cancel(job);
}
static void do_qmp_query_block_jobs_one(void *opaque, BlockDriverState *bs)
{
BlockJobInfoList **prev = opaque;
BlockJob *job = bs->job;
if (job) {
BlockJobInfoList *elem;
BlockJobInfo *info = g_new(BlockJobInfo, 1);
*info = (BlockJobInfo){
.type = g_strdup(job->job_type->job_type),
.device = g_strdup(bdrv_get_device_name(bs)),
.len = job->len,
.offset = job->offset,
.speed = job->speed,
};
elem = g_new0(BlockJobInfoList, 1);
elem->value = info;
(*prev)->next = elem;
*prev = elem;
}
}
BlockJobInfoList *qmp_query_block_jobs(Error **errp)
{
/* Dummy is a fake list element for holding the head pointer */
BlockJobInfoList dummy = {};
BlockJobInfoList *prev = &dummy;
bdrv_iterate(do_qmp_query_block_jobs_one, &prev);
return dummy.next;
}
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