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qemu / qemu / 8c89d50c10afdd98da82642ca5e9d7af4f1c18bd / . / block / rbd.c
blob: 5e102fea0d8637dc71f005109fba471c644eb191 [file] [log] [blame]
/*
* QEMU Block driver for RADOS (Ceph)
*
* Copyright (C) 2010-2011 Christian Brunner <chb@muc.de>,
* Josh Durgin <josh.durgin@dreamhost.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include <rbd/librbd.h>
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "qemu/module.h"
#include "qemu/option.h"
#include "block/block-io.h"
#include "block/block_int.h"
#include "block/qdict.h"
#include "crypto/secret.h"
#include "qemu/cutils.h"
#include "sysemu/replay.h"
#include "qapi/qmp/qstring.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qjson.h"
#include "qapi/qmp/qlist.h"
#include "qapi/qobject-input-visitor.h"
#include "qapi/qapi-visit-block-core.h"
/*
* When specifying the image filename use:
*
* rbd:poolname/devicename[@snapshotname][:option1=value1[:option2=value2...]]
*
* poolname must be the name of an existing rados pool.
*
* devicename is the name of the rbd image.
*
* Each option given is used to configure rados, and may be any valid
* Ceph option, "id", or "conf".
*
* The "id" option indicates what user we should authenticate as to
* the Ceph cluster. If it is excluded we will use the Ceph default
* (normally 'admin').
*
* The "conf" option specifies a Ceph configuration file to read. If
* it is not specified, we will read from the default Ceph locations
* (e.g., /etc/ceph/ceph.conf). To avoid reading _any_ configuration
* file, specify conf=/dev/null.
*
* Configuration values containing :, @, or = can be escaped with a
* leading "\".
*/
#define OBJ_MAX_SIZE (1UL << OBJ_DEFAULT_OBJ_ORDER)
#define RBD_MAX_SNAPS 100
#define RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN 8
static const char rbd_luks_header_verification[
RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN] = {
'L', 'U', 'K', 'S', 0xBA, 0xBE, 0, 1
};
static const char rbd_luks2_header_verification[
RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN] = {
'L', 'U', 'K', 'S', 0xBA, 0xBE, 0, 2
};
typedef enum {
RBD_AIO_READ,
RBD_AIO_WRITE,
RBD_AIO_DISCARD,
RBD_AIO_FLUSH,
RBD_AIO_WRITE_ZEROES
} RBDAIOCmd;
typedef struct BDRVRBDState {
rados_t cluster;
rados_ioctx_t io_ctx;
rbd_image_t image;
char *image_name;
char *snap;
char *namespace;
uint64_t image_size;
uint64_t object_size;
} BDRVRBDState;
typedef struct RBDTask {
BlockDriverState *bs;
Coroutine *co;
bool complete;
int64_t ret;
} RBDTask;
typedef struct RBDDiffIterateReq {
uint64_t offs;
uint64_t bytes;
bool exists;
} RBDDiffIterateReq;
static int qemu_rbd_connect(rados_t *cluster, rados_ioctx_t *io_ctx,
BlockdevOptionsRbd *opts, bool cache,
const char *keypairs, const char *secretid,
Error **errp);
static char *qemu_rbd_strchr(char *src, char delim)
{
char *p;
for (p = src; *p; ++p) {
if (*p == delim) {
return p;
}
if (*p == '\\' && p[1] != '\0') {
++p;
}
}
return NULL;
}
static char *qemu_rbd_next_tok(char *src, char delim, char **p)
{
char *end;
*p = NULL;
end = qemu_rbd_strchr(src, delim);
if (end) {
*p = end + 1;
*end = '\0';
}
return src;
}
static void qemu_rbd_unescape(char *src)
{
char *p;
for (p = src; *src; ++src, ++p) {
if (*src == '\\' && src[1] != '\0') {
src++;
}
*p = *src;
}
*p = '\0';
}
static void qemu_rbd_parse_filename(const char *filename, QDict *options,
Error **errp)
{
const char *start;
char *p, *buf;
QList *keypairs = NULL;
char *found_str, *image_name;
if (!strstart(filename, "rbd:", &start)) {
error_setg(errp, "File name must start with 'rbd:'");
return;
}
buf = g_strdup(start);
p = buf;
found_str = qemu_rbd_next_tok(p, '/', &p);
if (!p) {
error_setg(errp, "Pool name is required");
goto done;
}
qemu_rbd_unescape(found_str);
qdict_put_str(options, "pool", found_str);
if (qemu_rbd_strchr(p, '@')) {
image_name = qemu_rbd_next_tok(p, '@', &p);
found_str = qemu_rbd_next_tok(p, ':', &p);
qemu_rbd_unescape(found_str);
qdict_put_str(options, "snapshot", found_str);
} else {
image_name = qemu_rbd_next_tok(p, ':', &p);
}
/* Check for namespace in the image_name */
if (qemu_rbd_strchr(image_name, '/')) {
found_str = qemu_rbd_next_tok(image_name, '/', &image_name);
qemu_rbd_unescape(found_str);
qdict_put_str(options, "namespace", found_str);
} else {
qdict_put_str(options, "namespace", "");
}
qemu_rbd_unescape(image_name);
qdict_put_str(options, "image", image_name);
if (!p) {
goto done;
}
/* The following are essentially all key/value pairs, and we treat
* 'id' and 'conf' a bit special. Key/value pairs may be in any order. */
while (p) {
char *name, *value;
name = qemu_rbd_next_tok(p, '=', &p);
if (!p) {
error_setg(errp, "conf option %s has no value", name);
break;
}
qemu_rbd_unescape(name);
value = qemu_rbd_next_tok(p, ':', &p);
qemu_rbd_unescape(value);
if (!strcmp(name, "conf")) {
qdict_put_str(options, "conf", value);
} else if (!strcmp(name, "id")) {
qdict_put_str(options, "user", value);
} else {
/*
* We pass these internally to qemu_rbd_set_keypairs(), so
* we can get away with the simpler list of [ "key1",
* "value1", "key2", "value2" ] rather than a raw dict
* { "key1": "value1", "key2": "value2" } where we can't
* guarantee order, or even a more correct but complex
* [ { "key1": "value1" }, { "key2": "value2" } ]
*/
if (!keypairs) {
keypairs = qlist_new();
}
qlist_append_str(keypairs, name);
qlist_append_str(keypairs, value);
}
}
if (keypairs) {
qdict_put(options, "=keyvalue-pairs",
qstring_from_gstring(qobject_to_json(QOBJECT(keypairs))));
}
done:
g_free(buf);
qobject_unref(keypairs);
return;
}
static int qemu_rbd_set_auth(rados_t cluster, BlockdevOptionsRbd *opts,
Error **errp)
{
char *key, *acr;
int r;
GString *accu;
RbdAuthModeList *auth;
if (opts->key_secret) {
key = qcrypto_secret_lookup_as_base64(opts->key_secret, errp);
if (!key) {
return -EIO;
}
r = rados_conf_set(cluster, "key", key);
g_free(key);
if (r < 0) {
error_setg_errno(errp, -r, "Could not set 'key'");
return r;
}
}
if (opts->has_auth_client_required) {
accu = g_string_new("");
for (auth = opts->auth_client_required; auth; auth = auth->next) {
if (accu->str[0]) {
g_string_append_c(accu, ';');
}
g_string_append(accu, RbdAuthMode_str(auth->value));
}
acr = g_string_free(accu, FALSE);
r = rados_conf_set(cluster, "auth_client_required", acr);
g_free(acr);
if (r < 0) {
error_setg_errno(errp, -r,
"Could not set 'auth_client_required'");
return r;
}
}
return 0;
}
static int qemu_rbd_set_keypairs(rados_t cluster, const char *keypairs_json,
Error **errp)
{
QList *keypairs;
QString *name;
QString *value;
const char *key;
size_t remaining;
int ret = 0;
if (!keypairs_json) {
return ret;
}
keypairs = qobject_to(QList,
qobject_from_json(keypairs_json, &error_abort));
remaining = qlist_size(keypairs) / 2;
assert(remaining);
while (remaining--) {
name = qobject_to(QString, qlist_pop(keypairs));
value = qobject_to(QString, qlist_pop(keypairs));
assert(name && value);
key = qstring_get_str(name);
ret = rados_conf_set(cluster, key, qstring_get_str(value));
qobject_unref(value);
if (ret < 0) {
error_setg_errno(errp, -ret, "invalid conf option %s", key);
qobject_unref(name);
ret = -EINVAL;
break;
}
qobject_unref(name);
}
qobject_unref(keypairs);
return ret;
}
#ifdef LIBRBD_SUPPORTS_ENCRYPTION
static int qemu_rbd_convert_luks_options(
RbdEncryptionOptionsLUKSBase *luks_opts,
char **passphrase,
size_t *passphrase_len,
Error **errp)
{
return qcrypto_secret_lookup(luks_opts->key_secret, (uint8_t **)passphrase,
passphrase_len, errp);
}
static int qemu_rbd_convert_luks_create_options(
RbdEncryptionCreateOptionsLUKSBase *luks_opts,
rbd_encryption_algorithm_t *alg,
char **passphrase,
size_t *passphrase_len,
Error **errp)
{
int r = 0;
r = qemu_rbd_convert_luks_options(
qapi_RbdEncryptionCreateOptionsLUKSBase_base(luks_opts),
passphrase, passphrase_len, errp);
if (r < 0) {
return r;
}
if (luks_opts->has_cipher_alg) {
switch (luks_opts->cipher_alg) {
case QCRYPTO_CIPHER_ALG_AES_128: {
*alg = RBD_ENCRYPTION_ALGORITHM_AES128;
break;
}
case QCRYPTO_CIPHER_ALG_AES_256: {
*alg = RBD_ENCRYPTION_ALGORITHM_AES256;
break;
}
default: {
r = -ENOTSUP;
error_setg_errno(errp, -r, "unknown encryption algorithm: %u",
luks_opts->cipher_alg);
return r;
}
}
} else {
/* default alg */
*alg = RBD_ENCRYPTION_ALGORITHM_AES256;
}
return 0;
}
static int qemu_rbd_encryption_format(rbd_image_t image,
RbdEncryptionCreateOptions *encrypt,
Error **errp)
{
int r = 0;
g_autofree char *passphrase = NULL;
size_t passphrase_len;
rbd_encryption_format_t format;
rbd_encryption_options_t opts;
rbd_encryption_luks1_format_options_t luks_opts;
rbd_encryption_luks2_format_options_t luks2_opts;
size_t opts_size;
uint64_t raw_size, effective_size;
r = rbd_get_size(image, &raw_size);
if (r < 0) {
error_setg_errno(errp, -r, "cannot get raw image size");
return r;
}
switch (encrypt->format) {
case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS: {
memset(&luks_opts, 0, sizeof(luks_opts));
format = RBD_ENCRYPTION_FORMAT_LUKS1;
opts = &luks_opts;
opts_size = sizeof(luks_opts);
r = qemu_rbd_convert_luks_create_options(
qapi_RbdEncryptionCreateOptionsLUKS_base(&encrypt->u.luks),
&luks_opts.alg, &passphrase, &passphrase_len, errp);
if (r < 0) {
return r;
}
luks_opts.passphrase = passphrase;
luks_opts.passphrase_size = passphrase_len;
break;
}
case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS2: {
memset(&luks2_opts, 0, sizeof(luks2_opts));
format = RBD_ENCRYPTION_FORMAT_LUKS2;
opts = &luks2_opts;
opts_size = sizeof(luks2_opts);
r = qemu_rbd_convert_luks_create_options(
qapi_RbdEncryptionCreateOptionsLUKS2_base(
&encrypt->u.luks2),
&luks2_opts.alg, &passphrase, &passphrase_len, errp);
if (r < 0) {
return r;
}
luks2_opts.passphrase = passphrase;
luks2_opts.passphrase_size = passphrase_len;
break;
}
default: {
r = -ENOTSUP;
error_setg_errno(
errp, -r, "unknown image encryption format: %u",
encrypt->format);
return r;
}
}
r = rbd_encryption_format(image, format, opts, opts_size);
if (r < 0) {
error_setg_errno(errp, -r, "encryption format fail");
return r;
}
r = rbd_get_size(image, &effective_size);
if (r < 0) {
error_setg_errno(errp, -r, "cannot get effective image size");
return r;
}
r = rbd_resize(image, raw_size + (raw_size - effective_size));
if (r < 0) {
error_setg_errno(errp, -r, "cannot resize image after format");
return r;
}
return 0;
}
static int qemu_rbd_encryption_load(rbd_image_t image,
RbdEncryptionOptions *encrypt,
Error **errp)
{
int r = 0;
g_autofree char *passphrase = NULL;
size_t passphrase_len;
rbd_encryption_luks1_format_options_t luks_opts;
rbd_encryption_luks2_format_options_t luks2_opts;
rbd_encryption_format_t format;
rbd_encryption_options_t opts;
size_t opts_size;
switch (encrypt->format) {
case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS: {
memset(&luks_opts, 0, sizeof(luks_opts));
format = RBD_ENCRYPTION_FORMAT_LUKS1;
opts = &luks_opts;
opts_size = sizeof(luks_opts);
r = qemu_rbd_convert_luks_options(
qapi_RbdEncryptionOptionsLUKS_base(&encrypt->u.luks),
&passphrase, &passphrase_len, errp);
if (r < 0) {
return r;
}
luks_opts.passphrase = passphrase;
luks_opts.passphrase_size = passphrase_len;
break;
}
case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS2: {
memset(&luks2_opts, 0, sizeof(luks2_opts));
format = RBD_ENCRYPTION_FORMAT_LUKS2;
opts = &luks2_opts;
opts_size = sizeof(luks2_opts);
r = qemu_rbd_convert_luks_options(
qapi_RbdEncryptionOptionsLUKS2_base(&encrypt->u.luks2),
&passphrase, &passphrase_len, errp);
if (r < 0) {
return r;
}
luks2_opts.passphrase = passphrase;
luks2_opts.passphrase_size = passphrase_len;
break;
}
default: {
r = -ENOTSUP;
error_setg_errno(
errp, -r, "unknown image encryption format: %u",
encrypt->format);
return r;
}
}
r = rbd_encryption_load(image, format, opts, opts_size);
if (r < 0) {
error_setg_errno(errp, -r, "encryption load fail");
return r;
}
return 0;
}
#endif
/* FIXME Deprecate and remove keypairs or make it available in QMP. */
static int qemu_rbd_do_create(BlockdevCreateOptions *options,
const char *keypairs, const char *password_secret,
Error **errp)
{
BlockdevCreateOptionsRbd *opts = &options->u.rbd;
rados_t cluster;
rados_ioctx_t io_ctx;
int obj_order = 0;
int ret;
assert(options->driver == BLOCKDEV_DRIVER_RBD);
if (opts->location->snapshot) {
error_setg(errp, "Can't use snapshot name for image creation");
return -EINVAL;
}
#ifndef LIBRBD_SUPPORTS_ENCRYPTION
if (opts->encrypt) {
error_setg(errp, "RBD library does not support image encryption");
return -ENOTSUP;
}
#endif
if (opts->has_cluster_size) {
int64_t objsize = opts->cluster_size;
if ((objsize - 1) & objsize) { /* not a power of 2? */
error_setg(errp, "obj size needs to be power of 2");
return -EINVAL;
}
if (objsize < 4096) {
error_setg(errp, "obj size too small");
return -EINVAL;
}
obj_order = ctz32(objsize);
}
ret = qemu_rbd_connect(&cluster, &io_ctx, opts->location, false, keypairs,
password_secret, errp);
if (ret < 0) {
return ret;
}
ret = rbd_create(io_ctx, opts->location->image, opts->size, &obj_order);
if (ret < 0) {
error_setg_errno(errp, -ret, "error rbd create");
goto out;
}
#ifdef LIBRBD_SUPPORTS_ENCRYPTION
if (opts->encrypt) {
rbd_image_t image;
ret = rbd_open(io_ctx, opts->location->image, &image, NULL);
if (ret < 0) {
error_setg_errno(errp, -ret,
"error opening image '%s' for encryption format",
opts->location->image);
goto out;
}
ret = qemu_rbd_encryption_format(image, opts->encrypt, errp);
rbd_close(image);
if (ret < 0) {
/* encryption format fail, try removing the image */
rbd_remove(io_ctx, opts->location->image);
goto out;
}
}
#endif
ret = 0;
out:
rados_ioctx_destroy(io_ctx);
rados_shutdown(cluster);
return ret;
}
static int qemu_rbd_co_create(BlockdevCreateOptions *options, Error **errp)
{
return qemu_rbd_do_create(options, NULL, NULL, errp);
}
static int qemu_rbd_extract_encryption_create_options(
QemuOpts *opts,
RbdEncryptionCreateOptions **spec,
Error **errp)
{
QDict *opts_qdict;
QDict *encrypt_qdict;
Visitor *v;
int ret = 0;
opts_qdict = qemu_opts_to_qdict(opts, NULL);
qdict_extract_subqdict(opts_qdict, &encrypt_qdict, "encrypt.");
qobject_unref(opts_qdict);
if (!qdict_size(encrypt_qdict)) {
*spec = NULL;
goto exit;
}
/* Convert options into a QAPI object */
v = qobject_input_visitor_new_flat_confused(encrypt_qdict, errp);
if (!v) {
ret = -EINVAL;
goto exit;
}
visit_type_RbdEncryptionCreateOptions(v, NULL, spec, errp);
visit_free(v);
if (!*spec) {
ret = -EINVAL;
goto exit;
}
exit:
qobject_unref(encrypt_qdict);
return ret;
}
static int coroutine_fn qemu_rbd_co_create_opts(BlockDriver *drv,
const char *filename,
QemuOpts *opts,
Error **errp)
{
BlockdevCreateOptions *create_options;
BlockdevCreateOptionsRbd *rbd_opts;
BlockdevOptionsRbd *loc;
RbdEncryptionCreateOptions *encrypt = NULL;
Error *local_err = NULL;
const char *keypairs, *password_secret;
QDict *options = NULL;
int ret = 0;
create_options = g_new0(BlockdevCreateOptions, 1);
create_options->driver = BLOCKDEV_DRIVER_RBD;
rbd_opts = &create_options->u.rbd;
rbd_opts->location = g_new0(BlockdevOptionsRbd, 1);
password_secret = qemu_opt_get(opts, "password-secret");
/* Read out options */
rbd_opts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
BDRV_SECTOR_SIZE);
rbd_opts->cluster_size = qemu_opt_get_size_del(opts,
BLOCK_OPT_CLUSTER_SIZE, 0);
rbd_opts->has_cluster_size = (rbd_opts->cluster_size != 0);
options = qdict_new();
qemu_rbd_parse_filename(filename, options, &local_err);
if (local_err) {
ret = -EINVAL;
error_propagate(errp, local_err);
goto exit;
}
ret = qemu_rbd_extract_encryption_create_options(opts, &encrypt, errp);
if (ret < 0) {
goto exit;
}
rbd_opts->encrypt = encrypt;
/*
* Caution: while qdict_get_try_str() is fine, getting non-string
* types would require more care. When @options come from -blockdev
* or blockdev_add, its members are typed according to the QAPI
* schema, but when they come from -drive, they're all QString.
*/
loc = rbd_opts->location;
loc->pool = g_strdup(qdict_get_try_str(options, "pool"));
loc->conf = g_strdup(qdict_get_try_str(options, "conf"));
loc->user = g_strdup(qdict_get_try_str(options, "user"));
loc->q_namespace = g_strdup(qdict_get_try_str(options, "namespace"));
loc->image = g_strdup(qdict_get_try_str(options, "image"));
keypairs = qdict_get_try_str(options, "=keyvalue-pairs");
ret = qemu_rbd_do_create(create_options, keypairs, password_secret, errp);
if (ret < 0) {
goto exit;
}
exit:
qobject_unref(options);
qapi_free_BlockdevCreateOptions(create_options);
return ret;
}
static char *qemu_rbd_mon_host(BlockdevOptionsRbd *opts, Error **errp)
{
const char **vals;
const char *host, *port;
char *rados_str;
InetSocketAddressBaseList *p;
int i, cnt;
if (!opts->has_server) {
return NULL;
}
for (cnt = 0, p = opts->server; p; p = p->next) {
cnt++;
}
vals = g_new(const char *, cnt + 1);
for (i = 0, p = opts->server; p; p = p->next, i++) {
host = p->value->host;
port = p->value->port;
if (strchr(host, ':')) {
vals[i] = g_strdup_printf("[%s]:%s", host, port);
} else {
vals[i] = g_strdup_printf("%s:%s", host, port);
}
}
vals[i] = NULL;
rados_str = i ? g_strjoinv(";", (char **)vals) : NULL;
g_strfreev((char **)vals);
return rados_str;
}
static int qemu_rbd_connect(rados_t *cluster, rados_ioctx_t *io_ctx,
BlockdevOptionsRbd *opts, bool cache,
const char *keypairs, const char *secretid,
Error **errp)
{
char *mon_host = NULL;
Error *local_err = NULL;
int r;
if (secretid) {
if (opts->key_secret) {
error_setg(errp,
"Legacy 'password-secret' clashes with 'key-secret'");
return -EINVAL;
}
opts->key_secret = g_strdup(secretid);
}
mon_host = qemu_rbd_mon_host(opts, &local_err);
if (local_err) {
error_propagate(errp, local_err);
r = -EINVAL;
goto out;
}
r = rados_create(cluster, opts->user);
if (r < 0) {
error_setg_errno(errp, -r, "error initializing");
goto out;
}
/* try default location when conf=NULL, but ignore failure */
r = rados_conf_read_file(*cluster, opts->conf);
if (opts->conf && r < 0) {
error_setg_errno(errp, -r, "error reading conf file %s", opts->conf);
goto failed_shutdown;
}
r = qemu_rbd_set_keypairs(*cluster, keypairs, errp);
if (r < 0) {
goto failed_shutdown;
}
if (mon_host) {
r = rados_conf_set(*cluster, "mon_host", mon_host);
if (r < 0) {
goto failed_shutdown;
}
}
r = qemu_rbd_set_auth(*cluster, opts, errp);
if (r < 0) {
goto failed_shutdown;
}
/*
* Fallback to more conservative semantics if setting cache
* options fails. Ignore errors from setting rbd_cache because the
* only possible error is that the option does not exist, and
* librbd defaults to no caching. If write through caching cannot
* be set up, fall back to no caching.
*/
if (cache) {
rados_conf_set(*cluster, "rbd_cache", "true");
} else {
rados_conf_set(*cluster, "rbd_cache", "false");
}
r = rados_connect(*cluster);
if (r < 0) {
error_setg_errno(errp, -r, "error connecting");
goto failed_shutdown;
}
r = rados_ioctx_create(*cluster, opts->pool, io_ctx);
if (r < 0) {
error_setg_errno(errp, -r, "error opening pool %s", opts->pool);
goto failed_shutdown;
}
#ifdef HAVE_RBD_NAMESPACE_EXISTS
if (opts->q_namespace && strlen(opts->q_namespace) > 0) {
bool exists;
r = rbd_namespace_exists(*io_ctx, opts->q_namespace, &exists);
if (r < 0) {
error_setg_errno(errp, -r, "error checking namespace");
goto failed_ioctx_destroy;
}
if (!exists) {
error_setg(errp, "namespace '%s' does not exist",
opts->q_namespace);
r = -ENOENT;
goto failed_ioctx_destroy;
}
}
#endif
/*
* Set the namespace after opening the io context on the pool,
* if nspace == NULL or if nspace == "", it is just as we did nothing
*/
rados_ioctx_set_namespace(*io_ctx, opts->q_namespace);
r = 0;
goto out;
#ifdef HAVE_RBD_NAMESPACE_EXISTS
failed_ioctx_destroy:
rados_ioctx_destroy(*io_ctx);
#endif
failed_shutdown:
rados_shutdown(*cluster);
out:
g_free(mon_host);
return r;
}
static int qemu_rbd_convert_options(QDict *options, BlockdevOptionsRbd **opts,
Error **errp)
{
Visitor *v;
/* Convert the remaining options into a QAPI object */
v = qobject_input_visitor_new_flat_confused(options, errp);
if (!v) {
return -EINVAL;
}
visit_type_BlockdevOptionsRbd(v, NULL, opts, errp);
visit_free(v);
if (!opts) {
return -EINVAL;
}
return 0;
}
static int qemu_rbd_attempt_legacy_options(QDict *options,
BlockdevOptionsRbd **opts,
char **keypairs)
{
char *filename;
int r;
filename = g_strdup(qdict_get_try_str(options, "filename"));
if (!filename) {
return -EINVAL;
}
qdict_del(options, "filename");
qemu_rbd_parse_filename(filename, options, NULL);
/* keypairs freed by caller */
*keypairs = g_strdup(qdict_get_try_str(options, "=keyvalue-pairs"));
if (*keypairs) {
qdict_del(options, "=keyvalue-pairs");
}
r = qemu_rbd_convert_options(options, opts, NULL);
g_free(filename);
return r;
}
static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
BDRVRBDState *s = bs->opaque;
BlockdevOptionsRbd *opts = NULL;
const QDictEntry *e;
Error *local_err = NULL;
char *keypairs, *secretid;
rbd_image_info_t info;
int r;
keypairs = g_strdup(qdict_get_try_str(options, "=keyvalue-pairs"));
if (keypairs) {
qdict_del(options, "=keyvalue-pairs");
}
secretid = g_strdup(qdict_get_try_str(options, "password-secret"));
if (secretid) {
qdict_del(options, "password-secret");
}
r = qemu_rbd_convert_options(options, &opts, &local_err);
if (local_err) {
/* If keypairs are present, that means some options are present in
* the modern option format. Don't attempt to parse legacy option
* formats, as we won't support mixed usage. */
if (keypairs) {
error_propagate(errp, local_err);
goto out;
}
/* If the initial attempt to convert and process the options failed,
* we may be attempting to open an image file that has the rbd options
* specified in the older format consisting of all key/value pairs
* encoded in the filename. Go ahead and attempt to parse the
* filename, and see if we can pull out the required options. */
r = qemu_rbd_attempt_legacy_options(options, &opts, &keypairs);
if (r < 0) {
/* Propagate the original error, not the legacy parsing fallback
* error, as the latter was just a best-effort attempt. */
error_propagate(errp, local_err);
goto out;
}
/* Take care whenever deciding to actually deprecate; once this ability
* is removed, we will not be able to open any images with legacy-styled
* backing image strings. */
warn_report("RBD options encoded in the filename as keyvalue pairs "
"is deprecated");
}
/* Remove the processed options from the QDict (the visitor processes
* _all_ options in the QDict) */
while ((e = qdict_first(options))) {
qdict_del(options, e->key);
}
r = qemu_rbd_connect(&s->cluster, &s->io_ctx, opts,
!(flags & BDRV_O_NOCACHE), keypairs, secretid, errp);
if (r < 0) {
goto out;
}
s->snap = g_strdup(opts->snapshot);
s->image_name = g_strdup(opts->image);
/* rbd_open is always r/w */
r = rbd_open(s->io_ctx, s->image_name, &s->image, s->snap);
if (r < 0) {
error_setg_errno(errp, -r, "error reading header from %s",
s->image_name);
goto failed_open;
}
if (opts->encrypt) {
#ifdef LIBRBD_SUPPORTS_ENCRYPTION
r = qemu_rbd_encryption_load(s->image, opts->encrypt, errp);
if (r < 0) {
goto failed_post_open;
}
#else
r = -ENOTSUP;
error_setg(errp, "RBD library does not support image encryption");
goto failed_post_open;
#endif
}
r = rbd_stat(s->image, &info, sizeof(info));
if (r < 0) {
error_setg_errno(errp, -r, "error getting image info from %s",
s->image_name);
goto failed_post_open;
}
s->image_size = info.size;
s->object_size = info.obj_size;
/* If we are using an rbd snapshot, we must be r/o, otherwise
* leave as-is */
if (s->snap != NULL) {
r = bdrv_apply_auto_read_only(bs, "rbd snapshots are read-only", errp);
if (r < 0) {
goto failed_post_open;
}
}
#ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK;
#endif
/* When extending regular files, we get zeros from the OS */
bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE;
r = 0;
goto out;
failed_post_open:
rbd_close(s->image);
failed_open:
rados_ioctx_destroy(s->io_ctx);
g_free(s->snap);
g_free(s->image_name);
rados_shutdown(s->cluster);
out:
qapi_free_BlockdevOptionsRbd(opts);
g_free(keypairs);
g_free(secretid);
return r;
}
/* Since RBD is currently always opened R/W via the API,
* we just need to check if we are using a snapshot or not, in
* order to determine if we will allow it to be R/W */
static int qemu_rbd_reopen_prepare(BDRVReopenState *state,
BlockReopenQueue *queue, Error **errp)
{
BDRVRBDState *s = state->bs->opaque;
int ret = 0;
if (s->snap && state->flags & BDRV_O_RDWR) {
error_setg(errp,
"Cannot change node '%s' to r/w when using RBD snapshot",
bdrv_get_device_or_node_name(state->bs));
ret = -EINVAL;
}
return ret;
}
static void qemu_rbd_close(BlockDriverState *bs)
{
BDRVRBDState *s = bs->opaque;
rbd_close(s->image);
rados_ioctx_destroy(s->io_ctx);
g_free(s->snap);
g_free(s->image_name);
rados_shutdown(s->cluster);
}
/* Resize the RBD image and update the 'image_size' with the current size */
static int qemu_rbd_resize(BlockDriverState *bs, uint64_t size)
{
BDRVRBDState *s = bs->opaque;
int r;
r = rbd_resize(s->image, size);
if (r < 0) {
return r;
}
s->image_size = size;
return 0;
}
static void qemu_rbd_finish_bh(void *opaque)
{
RBDTask *task = opaque;
task->complete = true;
aio_co_wake(task->co);
}
/*
* This is the completion callback function for all rbd aio calls
* started from qemu_rbd_start_co().
*
* Note: this function is being called from a non qemu thread so
* we need to be careful about what we do here. Generally we only
* schedule a BH, and do the rest of the io completion handling
* from qemu_rbd_finish_bh() which runs in a qemu context.
*/
static void qemu_rbd_completion_cb(rbd_completion_t c, RBDTask *task)
{
task->ret = rbd_aio_get_return_value(c);
rbd_aio_release(c);
aio_bh_schedule_oneshot(bdrv_get_aio_context(task->bs),
qemu_rbd_finish_bh, task);
}
static int coroutine_fn qemu_rbd_start_co(BlockDriverState *bs,
uint64_t offset,
uint64_t bytes,
QEMUIOVector *qiov,
int flags,
RBDAIOCmd cmd)
{
BDRVRBDState *s = bs->opaque;
RBDTask task = { .bs = bs, .co = qemu_coroutine_self() };
rbd_completion_t c;
int r;
assert(!qiov || qiov->size == bytes);
if (cmd == RBD_AIO_WRITE || cmd == RBD_AIO_WRITE_ZEROES) {
/*
* RBD APIs don't allow us to write more than actual size, so in order
* to support growing images, we resize the image before write
* operations that exceed the current size.
*/
if (offset + bytes > s->image_size) {
int r = qemu_rbd_resize(bs, offset + bytes);
if (r < 0) {
return r;
}
}
}
r = rbd_aio_create_completion(&task,
(rbd_callback_t) qemu_rbd_completion_cb, &c);
if (r < 0) {
return r;
}
switch (cmd) {
case RBD_AIO_READ:
r = rbd_aio_readv(s->image, qiov->iov, qiov->niov, offset, c);
break;
case RBD_AIO_WRITE:
r = rbd_aio_writev(s->image, qiov->iov, qiov->niov, offset, c);
break;
case RBD_AIO_DISCARD:
r = rbd_aio_discard(s->image, offset, bytes, c);
break;
case RBD_AIO_FLUSH:
r = rbd_aio_flush(s->image, c);
break;
#ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
case RBD_AIO_WRITE_ZEROES: {
int zero_flags = 0;
#ifdef RBD_WRITE_ZEROES_FLAG_THICK_PROVISION
if (!(flags & BDRV_REQ_MAY_UNMAP)) {
zero_flags = RBD_WRITE_ZEROES_FLAG_THICK_PROVISION;
}
#endif
r = rbd_aio_write_zeroes(s->image, offset, bytes, c, zero_flags, 0);
break;
}
#endif
default:
r = -EINVAL;
}
if (r < 0) {
error_report("rbd request failed early: cmd %d offset %" PRIu64
" bytes %" PRIu64 " flags %d r %d (%s)", cmd, offset,
bytes, flags, r, strerror(-r));
rbd_aio_release(c);
return r;
}
while (!task.complete) {
qemu_coroutine_yield();
}
if (task.ret < 0) {
error_report("rbd request failed: cmd %d offset %" PRIu64 " bytes %"
PRIu64 " flags %d task.ret %" PRIi64 " (%s)", cmd, offset,
bytes, flags, task.ret, strerror(-task.ret));
return task.ret;
}
/* zero pad short reads */
if (cmd == RBD_AIO_READ && task.ret < qiov->size) {
qemu_iovec_memset(qiov, task.ret, 0, qiov->size - task.ret);
}
return 0;
}
static int
coroutine_fn qemu_rbd_co_preadv(BlockDriverState *bs, int64_t offset,
int64_t bytes, QEMUIOVector *qiov,
BdrvRequestFlags flags)
{
return qemu_rbd_start_co(bs, offset, bytes, qiov, flags, RBD_AIO_READ);
}
static int
coroutine_fn qemu_rbd_co_pwritev(BlockDriverState *bs, int64_t offset,
int64_t bytes, QEMUIOVector *qiov,
BdrvRequestFlags flags)
{
return qemu_rbd_start_co(bs, offset, bytes, qiov, flags, RBD_AIO_WRITE);
}
static int coroutine_fn qemu_rbd_co_flush(BlockDriverState *bs)
{
return qemu_rbd_start_co(bs, 0, 0, NULL, 0, RBD_AIO_FLUSH);
}
static int coroutine_fn qemu_rbd_co_pdiscard(BlockDriverState *bs,
int64_t offset, int64_t bytes)
{
return qemu_rbd_start_co(bs, offset, bytes, NULL, 0, RBD_AIO_DISCARD);
}
#ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
static int
coroutine_fn qemu_rbd_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
int64_t bytes, BdrvRequestFlags flags)
{
return qemu_rbd_start_co(bs, offset, bytes, NULL, flags,
RBD_AIO_WRITE_ZEROES);
}
#endif
static int coroutine_fn
qemu_rbd_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
{
BDRVRBDState *s = bs->opaque;
bdi->cluster_size = s->object_size;
return 0;
}
static ImageInfoSpecific *qemu_rbd_get_specific_info(BlockDriverState *bs,
Error **errp)
{
BDRVRBDState *s = bs->opaque;
ImageInfoSpecific *spec_info;
char buf[RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN] = {0};
int r;
if (s->image_size >= RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN) {
r = rbd_read(s->image, 0,
RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN, buf);
if (r < 0) {
error_setg_errno(errp, -r, "cannot read image start for probe");
return NULL;
}
}
spec_info = g_new(ImageInfoSpecific, 1);
*spec_info = (ImageInfoSpecific){
.type = IMAGE_INFO_SPECIFIC_KIND_RBD,
.u.rbd.data = g_new0(ImageInfoSpecificRbd, 1),
};
if (memcmp(buf, rbd_luks_header_verification,
RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN) == 0) {
spec_info->u.rbd.data->encryption_format =
RBD_IMAGE_ENCRYPTION_FORMAT_LUKS;
spec_info->u.rbd.data->has_encryption_format = true;
} else if (memcmp(buf, rbd_luks2_header_verification,
RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN) == 0) {
spec_info->u.rbd.data->encryption_format =
RBD_IMAGE_ENCRYPTION_FORMAT_LUKS2;
spec_info->u.rbd.data->has_encryption_format = true;
} else {
spec_info->u.rbd.data->has_encryption_format = false;
}
return spec_info;
}
/*
* rbd_diff_iterate2 allows to interrupt the exection by returning a negative
* value in the callback routine. Choose a value that does not conflict with
* an existing exitcode and return it if we want to prematurely stop the
* execution because we detected a change in the allocation status.
*/
#define QEMU_RBD_EXIT_DIFF_ITERATE2 -9000
static int qemu_rbd_diff_iterate_cb(uint64_t offs, size_t len,
int exists, void *opaque)
{
RBDDiffIterateReq *req = opaque;
assert(req->offs + req->bytes <= offs);
/* treat a hole like an unallocated area and bail out */
if (!exists) {
return 0;
}
if (!req->exists && offs > req->offs) {
/*
* we started in an unallocated area and hit the first allocated
* block. req->bytes must be set to the length of the unallocated area
* before the allocated area. stop further processing.
*/
req->bytes = offs - req->offs;
return QEMU_RBD_EXIT_DIFF_ITERATE2;
}
if (req->exists && offs > req->offs + req->bytes) {
/*
* we started in an allocated area and jumped over an unallocated area,
* req->bytes contains the length of the allocated area before the
* unallocated area. stop further processing.
*/
return QEMU_RBD_EXIT_DIFF_ITERATE2;
}
req->bytes += len;
req->exists = true;
return 0;
}
static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs,
bool want_zero, int64_t offset,
int64_t bytes, int64_t *pnum,
int64_t *map,
BlockDriverState **file)
{
BDRVRBDState *s = bs->opaque;
int status, r;
RBDDiffIterateReq req = { .offs = offset };
uint64_t features, flags;
uint64_t head = 0;
assert(offset + bytes <= s->image_size);
/* default to all sectors allocated */
status = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
*map = offset;
*file = bs;
*pnum = bytes;
/* check if RBD image supports fast-diff */
r = rbd_get_features(s->image, &features);
if (r < 0) {
return status;
}
if (!(features & RBD_FEATURE_FAST_DIFF)) {
return status;
}
/* check if RBD fast-diff result is valid */
r = rbd_get_flags(s->image, &flags);
if (r < 0) {
return status;
}
if (flags & RBD_FLAG_FAST_DIFF_INVALID) {
return status;
}
#if LIBRBD_VERSION_CODE < LIBRBD_VERSION(1, 17, 0)
/*
* librbd had a bug until early 2022 that affected all versions of ceph that
* supported fast-diff. This bug results in reporting of incorrect offsets
* if the offset parameter to rbd_diff_iterate2 is not object aligned.
* Work around this bug by rounding down the offset to object boundaries.
* This is OK because we call rbd_diff_iterate2 with whole_object = true.
* However, this workaround only works for non cloned images with default
* striping.
*
* See: https://tracker.ceph.com/issues/53784
*/
/* check if RBD image has non-default striping enabled */
if (features & RBD_FEATURE_STRIPINGV2) {
return status;
}
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
/*
* check if RBD image is a clone (= has a parent).
*
* rbd_get_parent_info is deprecated from Nautilus onwards, but the
* replacement rbd_get_parent is not present in Luminous and Mimic.
*/
if (rbd_get_parent_info(s->image, NULL, 0, NULL, 0, NULL, 0) != -ENOENT) {
return status;
}
#pragma GCC diagnostic pop
head = req.offs & (s->object_size - 1);
req.offs -= head;
bytes += head;
#endif
r = rbd_diff_iterate2(s->image, NULL, req.offs, bytes, true, true,
qemu_rbd_diff_iterate_cb, &req);
if (r < 0 && r != QEMU_RBD_EXIT_DIFF_ITERATE2) {
return status;
}
assert(req.bytes <= bytes);
if (!req.exists) {
if (r == 0) {
/*
* rbd_diff_iterate2 does not invoke callbacks for unallocated
* areas. This here catches the case where no callback was
* invoked at all (req.bytes == 0).
*/
assert(req.bytes == 0);
req.bytes = bytes;
}
status = BDRV_BLOCK_ZERO | BDRV_BLOCK_OFFSET_VALID;
}
assert(req.bytes > head);
*pnum = req.bytes - head;
return status;
}
static int64_t coroutine_fn qemu_rbd_co_getlength(BlockDriverState *bs)
{
BDRVRBDState *s = bs->opaque;
int r;
r = rbd_get_size(s->image, &s->image_size);
if (r < 0) {
return r;
}
return s->image_size;
}
static int coroutine_fn qemu_rbd_co_truncate(BlockDriverState *bs,
int64_t offset,
bool exact,
PreallocMode prealloc,
BdrvRequestFlags flags,
Error **errp)
{
int r;
if (prealloc != PREALLOC_MODE_OFF) {
error_setg(errp, "Unsupported preallocation mode '%s'",
PreallocMode_str(prealloc));
return -ENOTSUP;
}
r = qemu_rbd_resize(bs, offset);
if (r < 0) {
error_setg_errno(errp, -r, "Failed to resize file");
return r;
}
return 0;
}
static int qemu_rbd_snap_create(BlockDriverState *bs,
QEMUSnapshotInfo *sn_info)
{
BDRVRBDState *s = bs->opaque;
int r;
if (sn_info->name[0] == '\0') {
return -EINVAL; /* we need a name for rbd snapshots */
}
/*
* rbd snapshots are using the name as the user controlled unique identifier
* we can't use the rbd snapid for that purpose, as it can't be set
*/
if (sn_info->id_str[0] != '\0' &&
strcmp(sn_info->id_str, sn_info->name) != 0) {
return -EINVAL;
}
if (strlen(sn_info->name) >= sizeof(sn_info->id_str)) {
return -ERANGE;
}
r = rbd_snap_create(s->image, sn_info->name);
if (r < 0) {
error_report("failed to create snap: %s", strerror(-r));
return r;
}
return 0;
}
static int qemu_rbd_snap_remove(BlockDriverState *bs,
const char *snapshot_id,
const char *snapshot_name,
Error **errp)
{
BDRVRBDState *s = bs->opaque;
int r;
if (!snapshot_name) {
error_setg(errp, "rbd need a valid snapshot name");
return -EINVAL;
}
/* If snapshot_id is specified, it must be equal to name, see
qemu_rbd_snap_list() */
if (snapshot_id && strcmp(snapshot_id, snapshot_name)) {
error_setg(errp,
"rbd do not support snapshot id, it should be NULL or "
"equal to snapshot name");
return -EINVAL;
}
r = rbd_snap_remove(s->image, snapshot_name);
if (r < 0) {
error_setg_errno(errp, -r, "Failed to remove the snapshot");
}
return r;
}
static int qemu_rbd_snap_rollback(BlockDriverState *bs,
const char *snapshot_name)
{
BDRVRBDState *s = bs->opaque;
return rbd_snap_rollback(s->image, snapshot_name);
}
static int qemu_rbd_snap_list(BlockDriverState *bs,
QEMUSnapshotInfo **psn_tab)
{
BDRVRBDState *s = bs->opaque;
QEMUSnapshotInfo *sn_info, *sn_tab = NULL;
int i, snap_count;
rbd_snap_info_t *snaps;
int max_snaps = RBD_MAX_SNAPS;
do {
snaps = g_new(rbd_snap_info_t, max_snaps);
snap_count = rbd_snap_list(s->image, snaps, &max_snaps);
if (snap_count <= 0) {
g_free(snaps);
}
} while (snap_count == -ERANGE);
if (snap_count <= 0) {
goto done;
}
sn_tab = g_new0(QEMUSnapshotInfo, snap_count);
for (i = 0; i < snap_count; i++) {
const char *snap_name = snaps[i].name;
sn_info = sn_tab + i;
pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), snap_name);
pstrcpy(sn_info->name, sizeof(sn_info->name), snap_name);
sn_info->vm_state_size = snaps[i].size;
sn_info->date_sec = 0;
sn_info->date_nsec = 0;
sn_info->vm_clock_nsec = 0;
}
rbd_snap_list_end(snaps);
g_free(snaps);
done:
*psn_tab = sn_tab;
return snap_count;
}
static void coroutine_fn qemu_rbd_co_invalidate_cache(BlockDriverState *bs,
Error **errp)
{
BDRVRBDState *s = bs->opaque;
int r = rbd_invalidate_cache(s->image);
if (r < 0) {
error_setg_errno(errp, -r, "Failed to invalidate the cache");
}
}
static QemuOptsList qemu_rbd_create_opts = {
.name = "rbd-create-opts",
.head = QTAILQ_HEAD_INITIALIZER(qemu_rbd_create_opts.head),
.desc = {
{
.name = BLOCK_OPT_SIZE,
.type = QEMU_OPT_SIZE,
.help = "Virtual disk size"
},
{
.name = BLOCK_OPT_CLUSTER_SIZE,
.type = QEMU_OPT_SIZE,
.help = "RBD object size"
},
{
.name = "password-secret",
.type = QEMU_OPT_STRING,
.help = "ID of secret providing the password",
},
{
.name = "encrypt.format",
.type = QEMU_OPT_STRING,
.help = "Encrypt the image, format choices: 'luks', 'luks2'",
},
{
.name = "encrypt.cipher-alg",
.type = QEMU_OPT_STRING,
.help = "Name of encryption cipher algorithm"
" (allowed values: aes-128, aes-256)",
},
{
.name = "encrypt.key-secret",
.type = QEMU_OPT_STRING,
.help = "ID of secret providing LUKS passphrase",
},
{ /* end of list */ }
}
};
static const char *const qemu_rbd_strong_runtime_opts[] = {
"pool",
"namespace",
"image",
"conf",
"snapshot",
"user",
"server.",
"password-secret",
NULL
};
static BlockDriver bdrv_rbd = {
.format_name = "rbd",
.instance_size = sizeof(BDRVRBDState),
.bdrv_parse_filename = qemu_rbd_parse_filename,
.bdrv_file_open = qemu_rbd_open,
.bdrv_close = qemu_rbd_close,
.bdrv_reopen_prepare = qemu_rbd_reopen_prepare,
.bdrv_co_create = qemu_rbd_co_create,
.bdrv_co_create_opts = qemu_rbd_co_create_opts,
.bdrv_has_zero_init = bdrv_has_zero_init_1,
.bdrv_co_get_info = qemu_rbd_co_get_info,
.bdrv_get_specific_info = qemu_rbd_get_specific_info,
.create_opts = &qemu_rbd_create_opts,
.bdrv_co_getlength = qemu_rbd_co_getlength,
.bdrv_co_truncate = qemu_rbd_co_truncate,
.protocol_name = "rbd",
.bdrv_co_preadv = qemu_rbd_co_preadv,
.bdrv_co_pwritev = qemu_rbd_co_pwritev,
.bdrv_co_flush_to_disk = qemu_rbd_co_flush,
.bdrv_co_pdiscard = qemu_rbd_co_pdiscard,
#ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
.bdrv_co_pwrite_zeroes = qemu_rbd_co_pwrite_zeroes,
#endif
.bdrv_co_block_status = qemu_rbd_co_block_status,
.bdrv_snapshot_create = qemu_rbd_snap_create,
.bdrv_snapshot_delete = qemu_rbd_snap_remove,
.bdrv_snapshot_list = qemu_rbd_snap_list,
.bdrv_snapshot_goto = qemu_rbd_snap_rollback,
.bdrv_co_invalidate_cache = qemu_rbd_co_invalidate_cache,
.strong_runtime_opts = qemu_rbd_strong_runtime_opts,
};
static void bdrv_rbd_init(void)
{
bdrv_register(&bdrv_rbd);
}
block_init(bdrv_rbd_init);