qemu-e2k/block/nbd.c

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/*
* QEMU Block driver for NBD
*
* Copyright (C) 2008 Bull S.A.S.
* Author: Laurent Vivier <Laurent.Vivier@bull.net>
*
* Some parts:
* Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws>
*
* 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"
#include "block/nbd-client.h"
2016-03-14 09:01:28 +01:00
#include "qapi/error.h"
#include "qemu/uri.h"
#include "block/block_int.h"
#include "qemu/module.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qjson.h"
#include "qapi/qmp/qint.h"
#include "qapi/qmp/qstring.h"
#include "qemu/cutils.h"
#define EN_OPTSTR ":exportname="
typedef struct BDRVNBDState {
NbdClientSession client;
} BDRVNBDState;
static int nbd_parse_uri(const char *filename, QDict *options)
{
URI *uri;
const char *p;
QueryParams *qp = NULL;
int ret = 0;
bool is_unix;
uri = uri_parse(filename);
if (!uri) {
return -EINVAL;
}
/* transport */
if (!strcmp(uri->scheme, "nbd")) {
is_unix = false;
} else if (!strcmp(uri->scheme, "nbd+tcp")) {
is_unix = false;
} else if (!strcmp(uri->scheme, "nbd+unix")) {
is_unix = true;
} else {
ret = -EINVAL;
goto out;
}
p = uri->path ? uri->path : "/";
p += strspn(p, "/");
if (p[0]) {
qdict_put(options, "export", qstring_from_str(p));
}
qp = query_params_parse(uri->query);
if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) {
ret = -EINVAL;
goto out;
}
if (is_unix) {
/* nbd+unix:///export?socket=path */
if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) {
ret = -EINVAL;
goto out;
}
qdict_put(options, "path", qstring_from_str(qp->p[0].value));
} else {
QString *host;
/* nbd[+tcp]://host[:port]/export */
if (!uri->server) {
ret = -EINVAL;
goto out;
}
/* strip braces from literal IPv6 address */
if (uri->server[0] == '[') {
host = qstring_from_substr(uri->server, 1,
strlen(uri->server) - 2);
} else {
host = qstring_from_str(uri->server);
}
qdict_put(options, "host", host);
if (uri->port) {
char* port_str = g_strdup_printf("%d", uri->port);
qdict_put(options, "port", qstring_from_str(port_str));
g_free(port_str);
}
}
out:
if (qp) {
query_params_free(qp);
}
uri_free(uri);
return ret;
}
static void nbd_parse_filename(const char *filename, QDict *options,
Error **errp)
{
char *file;
char *export_name;
const char *host_spec;
const char *unixpath;
if (qdict_haskey(options, "host")
|| qdict_haskey(options, "port")
|| qdict_haskey(options, "path"))
{
error_setg(errp, "host/port/path and a file name may not be specified "
"at the same time");
return;
}
if (strstr(filename, "://")) {
int ret = nbd_parse_uri(filename, options);
if (ret < 0) {
error_setg(errp, "No valid URL specified");
}
return;
}
file = g_strdup(filename);
export_name = strstr(file, EN_OPTSTR);
if (export_name) {
if (export_name[strlen(EN_OPTSTR)] == 0) {
goto out;
}
export_name[0] = 0; /* truncate 'file' */
export_name += strlen(EN_OPTSTR);
qdict_put(options, "export", qstring_from_str(export_name));
}
/* extract the host_spec - fail if it's not nbd:... */
if (!strstart(file, "nbd:", &host_spec)) {
error_setg(errp, "File name string for NBD must start with 'nbd:'");
goto out;
}
if (!*host_spec) {
goto out;
}
/* are we a UNIX or TCP socket? */
if (strstart(host_spec, "unix:", &unixpath)) {
qdict_put(options, "path", qstring_from_str(unixpath));
} else {
InetSocketAddress *addr = NULL;
addr = inet_parse(host_spec, errp);
if (!addr) {
goto out;
}
qdict_put(options, "host", qstring_from_str(addr->host));
qdict_put(options, "port", qstring_from_str(addr->port));
qapi_free_InetSocketAddress(addr);
}
out:
g_free(file);
}
static SocketAddress *nbd_config(BDRVNBDState *s, QDict *options, char **export,
Error **errp)
{
SocketAddress *saddr;
if (qdict_haskey(options, "path") == qdict_haskey(options, "host")) {
if (qdict_haskey(options, "path")) {
error_setg(errp, "path and host may not be used at the same time.");
} else {
error_setg(errp, "one of path and host must be specified.");
}
return NULL;
}
saddr = g_new0(SocketAddress, 1);
if (qdict_haskey(options, "path")) {
UnixSocketAddress *q_unix;
saddr->type = SOCKET_ADDRESS_KIND_UNIX;
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
q_unix = saddr->u.q_unix.data = g_new0(UnixSocketAddress, 1);
q_unix->path = g_strdup(qdict_get_str(options, "path"));
qdict_del(options, "path");
} else {
InetSocketAddress *inet;
saddr->type = SOCKET_ADDRESS_KIND_INET;
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
inet = saddr->u.inet.data = g_new0(InetSocketAddress, 1);
inet->host = g_strdup(qdict_get_str(options, "host"));
if (!qdict_get_try_str(options, "port")) {
inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
} else {
inet->port = g_strdup(qdict_get_str(options, "port"));
}
qdict_del(options, "host");
qdict_del(options, "port");
}
s->client.is_unix = saddr->type == SOCKET_ADDRESS_KIND_UNIX;
*export = g_strdup(qdict_get_try_str(options, "export"));
if (*export) {
qdict_del(options, "export");
}
return saddr;
}
NbdClientSession *nbd_get_client_session(BlockDriverState *bs)
{
BDRVNBDState *s = bs->opaque;
return &s->client;
}
static QIOChannelSocket *nbd_establish_connection(SocketAddress *saddr,
Error **errp)
{
QIOChannelSocket *sioc;
Error *local_err = NULL;
sioc = qio_channel_socket_new();
qio_channel_socket_connect_sync(sioc,
saddr,
&local_err);
if (local_err) {
error_propagate(errp, local_err);
return NULL;
}
qio_channel_set_delay(QIO_CHANNEL(sioc), false);
return sioc;
}
static QCryptoTLSCreds *nbd_get_tls_creds(const char *id, Error **errp)
{
Object *obj;
QCryptoTLSCreds *creds;
obj = object_resolve_path_component(
object_get_objects_root(), id);
if (!obj) {
error_setg(errp, "No TLS credentials with id '%s'",
id);
return NULL;
}
creds = (QCryptoTLSCreds *)
object_dynamic_cast(obj, TYPE_QCRYPTO_TLS_CREDS);
if (!creds) {
error_setg(errp, "Object with id '%s' is not TLS credentials",
id);
return NULL;
}
if (creds->endpoint != QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
error_setg(errp,
"Expecting TLS credentials with a client endpoint");
return NULL;
}
object_ref(obj);
return creds;
}
static int nbd_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
BDRVNBDState *s = bs->opaque;
char *export = NULL;
QIOChannelSocket *sioc = NULL;
SocketAddress *saddr;
const char *tlscredsid;
QCryptoTLSCreds *tlscreds = NULL;
const char *hostname = NULL;
int ret = -EINVAL;
/* Pop the config into our state object. Exit if invalid. */
saddr = nbd_config(s, options, &export, errp);
if (!saddr) {
goto error;
}
tlscredsid = g_strdup(qdict_get_try_str(options, "tls-creds"));
if (tlscredsid) {
qdict_del(options, "tls-creds");
tlscreds = nbd_get_tls_creds(tlscredsid, errp);
if (!tlscreds) {
goto error;
}
if (saddr->type != SOCKET_ADDRESS_KIND_INET) {
error_setg(errp, "TLS only supported over IP sockets");
goto error;
}
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
hostname = saddr->u.inet.data->host;
}
/* establish TCP connection, return error if it fails
* TODO: Configurable retry-until-timeout behaviour.
*/
sioc = nbd_establish_connection(saddr, errp);
if (!sioc) {
ret = -ECONNREFUSED;
goto error;
}
/* NBD handshake */
ret = nbd_client_init(bs, sioc, export,
tlscreds, hostname, errp);
error:
if (sioc) {
object_unref(OBJECT(sioc));
}
if (tlscreds) {
object_unref(OBJECT(tlscreds));
}
qapi_free_SocketAddress(saddr);
g_free(export);
return ret;
}
static int nbd_co_readv(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, QEMUIOVector *qiov)
{
return nbd_client_co_readv(bs, sector_num, nb_sectors, qiov);
}
static int nbd_co_flush(BlockDriverState *bs)
{
return nbd_client_co_flush(bs);
}
static void nbd_refresh_limits(BlockDriverState *bs, Error **errp)
{
bs->bl.max_discard = UINT32_MAX >> BDRV_SECTOR_BITS;
bs->bl.max_transfer_length = UINT32_MAX >> BDRV_SECTOR_BITS;
}
static int nbd_co_discard(BlockDriverState *bs, int64_t sector_num,
int nb_sectors)
{
return nbd_client_co_discard(bs, sector_num, nb_sectors);
}
static void nbd_close(BlockDriverState *bs)
{
nbd_client_close(bs);
}
static int64_t nbd_getlength(BlockDriverState *bs)
{
BDRVNBDState *s = bs->opaque;
return s->client.size;
}
static void nbd_detach_aio_context(BlockDriverState *bs)
{
nbd_client_detach_aio_context(bs);
}
static void nbd_attach_aio_context(BlockDriverState *bs,
AioContext *new_context)
{
nbd_client_attach_aio_context(bs, new_context);
}
static void nbd_refresh_filename(BlockDriverState *bs, QDict *options)
{
QDict *opts = qdict_new();
const char *path = qdict_get_try_str(options, "path");
const char *host = qdict_get_try_str(options, "host");
const char *port = qdict_get_try_str(options, "port");
const char *export = qdict_get_try_str(options, "export");
const char *tlscreds = qdict_get_try_str(options, "tls-creds");
qdict_put_obj(opts, "driver", QOBJECT(qstring_from_str("nbd")));
if (path && export) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nbd+unix:///%s?socket=%s", export, path);
} else if (path && !export) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nbd+unix://?socket=%s", path);
} else if (!path && export && port) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nbd://%s:%s/%s", host, port, export);
} else if (!path && export && !port) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nbd://%s/%s", host, export);
} else if (!path && !export && port) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nbd://%s:%s", host, port);
} else if (!path && !export && !port) {
snprintf(bs->exact_filename, sizeof(bs->exact_filename),
"nbd://%s", host);
}
if (path) {
qdict_put_obj(opts, "path", QOBJECT(qstring_from_str(path)));
} else if (port) {
qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(host)));
qdict_put_obj(opts, "port", QOBJECT(qstring_from_str(port)));
} else {
qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(host)));
}
if (export) {
qdict_put_obj(opts, "export", QOBJECT(qstring_from_str(export)));
}
if (tlscreds) {
qdict_put_obj(opts, "tls-creds", QOBJECT(qstring_from_str(tlscreds)));
}
bs->full_open_options = opts;
}
static BlockDriver bdrv_nbd = {
.format_name = "nbd",
.protocol_name = "nbd",
.instance_size = sizeof(BDRVNBDState),
.bdrv_parse_filename = nbd_parse_filename,
.bdrv_file_open = nbd_open,
.bdrv_co_readv = nbd_co_readv,
.bdrv_co_writev_flags = nbd_client_co_writev,
.bdrv_close = nbd_close,
.bdrv_co_flush_to_os = nbd_co_flush,
.bdrv_co_discard = nbd_co_discard,
.bdrv_refresh_limits = nbd_refresh_limits,
.bdrv_getlength = nbd_getlength,
.bdrv_detach_aio_context = nbd_detach_aio_context,
.bdrv_attach_aio_context = nbd_attach_aio_context,
.bdrv_refresh_filename = nbd_refresh_filename,
};
static BlockDriver bdrv_nbd_tcp = {
.format_name = "nbd",
.protocol_name = "nbd+tcp",
.instance_size = sizeof(BDRVNBDState),
.bdrv_parse_filename = nbd_parse_filename,
.bdrv_file_open = nbd_open,
.bdrv_co_readv = nbd_co_readv,
.bdrv_co_writev_flags = nbd_client_co_writev,
.bdrv_close = nbd_close,
.bdrv_co_flush_to_os = nbd_co_flush,
.bdrv_co_discard = nbd_co_discard,
.bdrv_refresh_limits = nbd_refresh_limits,
.bdrv_getlength = nbd_getlength,
.bdrv_detach_aio_context = nbd_detach_aio_context,
.bdrv_attach_aio_context = nbd_attach_aio_context,
.bdrv_refresh_filename = nbd_refresh_filename,
};
static BlockDriver bdrv_nbd_unix = {
.format_name = "nbd",
.protocol_name = "nbd+unix",
.instance_size = sizeof(BDRVNBDState),
.bdrv_parse_filename = nbd_parse_filename,
.bdrv_file_open = nbd_open,
.bdrv_co_readv = nbd_co_readv,
.bdrv_co_writev_flags = nbd_client_co_writev,
.bdrv_close = nbd_close,
.bdrv_co_flush_to_os = nbd_co_flush,
.bdrv_co_discard = nbd_co_discard,
.bdrv_refresh_limits = nbd_refresh_limits,
.bdrv_getlength = nbd_getlength,
.bdrv_detach_aio_context = nbd_detach_aio_context,
.bdrv_attach_aio_context = nbd_attach_aio_context,
.bdrv_refresh_filename = nbd_refresh_filename,
};
static void bdrv_nbd_init(void)
{
bdrv_register(&bdrv_nbd);
bdrv_register(&bdrv_nbd_tcp);
bdrv_register(&bdrv_nbd_unix);
}
block_init(bdrv_nbd_init);