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-rw-r--r--src/block/rbd.c967
1 files changed, 967 insertions, 0 deletions
diff --git a/src/block/rbd.c b/src/block/rbd.c
new file mode 100644
index 0000000..a60a19d
--- /dev/null
+++ b/src/block/rbd.c
@@ -0,0 +1,967 @@
+/*
+ * 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 <inttypes.h>
+
+#include "qemu-common.h"
+#include "qemu/error-report.h"
+#include "block/block_int.h"
+
+#include <rbd/librbd.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 "\".
+ */
+
+/* rbd_aio_discard added in 0.1.2 */
+#if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 2)
+#define LIBRBD_SUPPORTS_DISCARD
+#else
+#undef LIBRBD_SUPPORTS_DISCARD
+#endif
+
+#define OBJ_MAX_SIZE (1UL << OBJ_DEFAULT_OBJ_ORDER)
+
+#define RBD_MAX_CONF_NAME_SIZE 128
+#define RBD_MAX_CONF_VAL_SIZE 512
+#define RBD_MAX_CONF_SIZE 1024
+#define RBD_MAX_POOL_NAME_SIZE 128
+#define RBD_MAX_SNAP_NAME_SIZE 128
+#define RBD_MAX_SNAPS 100
+
+typedef enum {
+ RBD_AIO_READ,
+ RBD_AIO_WRITE,
+ RBD_AIO_DISCARD,
+ RBD_AIO_FLUSH
+} RBDAIOCmd;
+
+typedef struct RBDAIOCB {
+ BlockAIOCB common;
+ QEMUBH *bh;
+ int64_t ret;
+ QEMUIOVector *qiov;
+ char *bounce;
+ RBDAIOCmd cmd;
+ int error;
+ struct BDRVRBDState *s;
+} RBDAIOCB;
+
+typedef struct RADOSCB {
+ RBDAIOCB *acb;
+ struct BDRVRBDState *s;
+ int64_t size;
+ char *buf;
+ int64_t ret;
+} RADOSCB;
+
+typedef struct BDRVRBDState {
+ rados_t cluster;
+ rados_ioctx_t io_ctx;
+ rbd_image_t image;
+ char name[RBD_MAX_IMAGE_NAME_SIZE];
+ char *snap;
+} BDRVRBDState;
+
+static int qemu_rbd_next_tok(char *dst, int dst_len,
+ char *src, char delim,
+ const char *name,
+ char **p, Error **errp)
+{
+ int l;
+ char *end;
+
+ *p = NULL;
+
+ if (delim != '\0') {
+ for (end = src; *end; ++end) {
+ if (*end == delim) {
+ break;
+ }
+ if (*end == '\\' && end[1] != '\0') {
+ end++;
+ }
+ }
+ if (*end == delim) {
+ *p = end + 1;
+ *end = '\0';
+ }
+ }
+ l = strlen(src);
+ if (l >= dst_len) {
+ error_setg(errp, "%s too long", name);
+ return -EINVAL;
+ } else if (l == 0) {
+ error_setg(errp, "%s too short", name);
+ return -EINVAL;
+ }
+
+ pstrcpy(dst, dst_len, src);
+
+ return 0;
+}
+
+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 int qemu_rbd_parsename(const char *filename,
+ char *pool, int pool_len,
+ char *snap, int snap_len,
+ char *name, int name_len,
+ char *conf, int conf_len,
+ Error **errp)
+{
+ const char *start;
+ char *p, *buf;
+ int ret;
+
+ if (!strstart(filename, "rbd:", &start)) {
+ error_setg(errp, "File name must start with 'rbd:'");
+ return -EINVAL;
+ }
+
+ buf = g_strdup(start);
+ p = buf;
+ *snap = '\0';
+ *conf = '\0';
+
+ ret = qemu_rbd_next_tok(pool, pool_len, p,
+ '/', "pool name", &p, errp);
+ if (ret < 0 || !p) {
+ ret = -EINVAL;
+ goto done;
+ }
+ qemu_rbd_unescape(pool);
+
+ if (strchr(p, '@')) {
+ ret = qemu_rbd_next_tok(name, name_len, p,
+ '@', "object name", &p, errp);
+ if (ret < 0) {
+ goto done;
+ }
+ ret = qemu_rbd_next_tok(snap, snap_len, p,
+ ':', "snap name", &p, errp);
+ qemu_rbd_unescape(snap);
+ } else {
+ ret = qemu_rbd_next_tok(name, name_len, p,
+ ':', "object name", &p, errp);
+ }
+ qemu_rbd_unescape(name);
+ if (ret < 0 || !p) {
+ goto done;
+ }
+
+ ret = qemu_rbd_next_tok(conf, conf_len, p,
+ '\0', "configuration", &p, errp);
+
+done:
+ g_free(buf);
+ return ret;
+}
+
+static char *qemu_rbd_parse_clientname(const char *conf, char *clientname)
+{
+ const char *p = conf;
+
+ while (*p) {
+ int len;
+ const char *end = strchr(p, ':');
+
+ if (end) {
+ len = end - p;
+ } else {
+ len = strlen(p);
+ }
+
+ if (strncmp(p, "id=", 3) == 0) {
+ len -= 3;
+ strncpy(clientname, p + 3, len);
+ clientname[len] = '\0';
+ return clientname;
+ }
+ if (end == NULL) {
+ break;
+ }
+ p = end + 1;
+ }
+ return NULL;
+}
+
+static int qemu_rbd_set_conf(rados_t cluster, const char *conf,
+ bool only_read_conf_file,
+ Error **errp)
+{
+ char *p, *buf;
+ char name[RBD_MAX_CONF_NAME_SIZE];
+ char value[RBD_MAX_CONF_VAL_SIZE];
+ int ret = 0;
+
+ buf = g_strdup(conf);
+ p = buf;
+
+ while (p) {
+ ret = qemu_rbd_next_tok(name, sizeof(name), p,
+ '=', "conf option name", &p, errp);
+ if (ret < 0) {
+ break;
+ }
+ qemu_rbd_unescape(name);
+
+ if (!p) {
+ error_setg(errp, "conf option %s has no value", name);
+ ret = -EINVAL;
+ break;
+ }
+
+ ret = qemu_rbd_next_tok(value, sizeof(value), p,
+ ':', "conf option value", &p, errp);
+ if (ret < 0) {
+ break;
+ }
+ qemu_rbd_unescape(value);
+
+ if (strcmp(name, "conf") == 0) {
+ /* read the conf file alone, so it doesn't override more
+ specific settings for a particular device */
+ if (only_read_conf_file) {
+ ret = rados_conf_read_file(cluster, value);
+ if (ret < 0) {
+ error_setg(errp, "error reading conf file %s", value);
+ break;
+ }
+ }
+ } else if (strcmp(name, "id") == 0) {
+ /* ignore, this is parsed by qemu_rbd_parse_clientname() */
+ } else if (!only_read_conf_file) {
+ ret = rados_conf_set(cluster, name, value);
+ if (ret < 0) {
+ error_setg(errp, "invalid conf option %s", name);
+ ret = -EINVAL;
+ break;
+ }
+ }
+ }
+
+ g_free(buf);
+ return ret;
+}
+
+static int qemu_rbd_create(const char *filename, QemuOpts *opts, Error **errp)
+{
+ Error *local_err = NULL;
+ int64_t bytes = 0;
+ int64_t objsize;
+ int obj_order = 0;
+ char pool[RBD_MAX_POOL_NAME_SIZE];
+ char name[RBD_MAX_IMAGE_NAME_SIZE];
+ char snap_buf[RBD_MAX_SNAP_NAME_SIZE];
+ char conf[RBD_MAX_CONF_SIZE];
+ char clientname_buf[RBD_MAX_CONF_SIZE];
+ char *clientname;
+ rados_t cluster;
+ rados_ioctx_t io_ctx;
+ int ret;
+
+ if (qemu_rbd_parsename(filename, pool, sizeof(pool),
+ snap_buf, sizeof(snap_buf),
+ name, sizeof(name),
+ conf, sizeof(conf), &local_err) < 0) {
+ error_propagate(errp, local_err);
+ return -EINVAL;
+ }
+
+ /* Read out options */
+ bytes = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
+ BDRV_SECTOR_SIZE);
+ objsize = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE, 0);
+ if (objsize) {
+ 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);
+ }
+
+ clientname = qemu_rbd_parse_clientname(conf, clientname_buf);
+ if (rados_create(&cluster, clientname) < 0) {
+ error_setg(errp, "error initializing");
+ return -EIO;
+ }
+
+ if (strstr(conf, "conf=") == NULL) {
+ /* try default location, but ignore failure */
+ rados_conf_read_file(cluster, NULL);
+ } else if (conf[0] != '\0' &&
+ qemu_rbd_set_conf(cluster, conf, true, &local_err) < 0) {
+ rados_shutdown(cluster);
+ error_propagate(errp, local_err);
+ return -EIO;
+ }
+
+ if (conf[0] != '\0' &&
+ qemu_rbd_set_conf(cluster, conf, false, &local_err) < 0) {
+ rados_shutdown(cluster);
+ error_propagate(errp, local_err);
+ return -EIO;
+ }
+
+ if (rados_connect(cluster) < 0) {
+ error_setg(errp, "error connecting");
+ rados_shutdown(cluster);
+ return -EIO;
+ }
+
+ if (rados_ioctx_create(cluster, pool, &io_ctx) < 0) {
+ error_setg(errp, "error opening pool %s", pool);
+ rados_shutdown(cluster);
+ return -EIO;
+ }
+
+ ret = rbd_create(io_ctx, name, bytes, &obj_order);
+ rados_ioctx_destroy(io_ctx);
+ rados_shutdown(cluster);
+
+ return ret;
+}
+
+/*
+ * This aio completion is being called from rbd_finish_bh() and runs in qemu
+ * BH context.
+ */
+static void qemu_rbd_complete_aio(RADOSCB *rcb)
+{
+ RBDAIOCB *acb = rcb->acb;
+ int64_t r;
+
+ r = rcb->ret;
+
+ if (acb->cmd != RBD_AIO_READ) {
+ if (r < 0) {
+ acb->ret = r;
+ acb->error = 1;
+ } else if (!acb->error) {
+ acb->ret = rcb->size;
+ }
+ } else {
+ if (r < 0) {
+ memset(rcb->buf, 0, rcb->size);
+ acb->ret = r;
+ acb->error = 1;
+ } else if (r < rcb->size) {
+ memset(rcb->buf + r, 0, rcb->size - r);
+ if (!acb->error) {
+ acb->ret = rcb->size;
+ }
+ } else if (!acb->error) {
+ acb->ret = r;
+ }
+ }
+
+ g_free(rcb);
+
+ if (acb->cmd == RBD_AIO_READ) {
+ qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size);
+ }
+ qemu_vfree(acb->bounce);
+ acb->common.cb(acb->common.opaque, (acb->ret > 0 ? 0 : acb->ret));
+
+ qemu_aio_unref(acb);
+}
+
+/* TODO Convert to fine grained options */
+static QemuOptsList runtime_opts = {
+ .name = "rbd",
+ .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
+ .desc = {
+ {
+ .name = "filename",
+ .type = QEMU_OPT_STRING,
+ .help = "Specification of the rbd image",
+ },
+ { /* end of list */ }
+ },
+};
+
+static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ BDRVRBDState *s = bs->opaque;
+ char pool[RBD_MAX_POOL_NAME_SIZE];
+ char snap_buf[RBD_MAX_SNAP_NAME_SIZE];
+ char conf[RBD_MAX_CONF_SIZE];
+ char clientname_buf[RBD_MAX_CONF_SIZE];
+ char *clientname;
+ QemuOpts *opts;
+ Error *local_err = NULL;
+ const char *filename;
+ int r;
+
+ opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
+ qemu_opts_absorb_qdict(opts, options, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ qemu_opts_del(opts);
+ return -EINVAL;
+ }
+
+ filename = qemu_opt_get(opts, "filename");
+
+ if (qemu_rbd_parsename(filename, pool, sizeof(pool),
+ snap_buf, sizeof(snap_buf),
+ s->name, sizeof(s->name),
+ conf, sizeof(conf), errp) < 0) {
+ r = -EINVAL;
+ goto failed_opts;
+ }
+
+ clientname = qemu_rbd_parse_clientname(conf, clientname_buf);
+ r = rados_create(&s->cluster, clientname);
+ if (r < 0) {
+ error_setg(errp, "error initializing");
+ goto failed_opts;
+ }
+
+ s->snap = NULL;
+ if (snap_buf[0] != '\0') {
+ s->snap = g_strdup(snap_buf);
+ }
+
+ if (strstr(conf, "conf=") == NULL) {
+ /* try default location, but ignore failure */
+ rados_conf_read_file(s->cluster, NULL);
+ } else if (conf[0] != '\0') {
+ r = qemu_rbd_set_conf(s->cluster, conf, true, errp);
+ if (r < 0) {
+ goto failed_shutdown;
+ }
+ }
+
+ if (conf[0] != '\0') {
+ r = qemu_rbd_set_conf(s->cluster, conf, false, 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 (flags & BDRV_O_NOCACHE) {
+ rados_conf_set(s->cluster, "rbd_cache", "false");
+ } else {
+ rados_conf_set(s->cluster, "rbd_cache", "true");
+ }
+
+ r = rados_connect(s->cluster);
+ if (r < 0) {
+ error_setg(errp, "error connecting");
+ goto failed_shutdown;
+ }
+
+ r = rados_ioctx_create(s->cluster, pool, &s->io_ctx);
+ if (r < 0) {
+ error_setg(errp, "error opening pool %s", pool);
+ goto failed_shutdown;
+ }
+
+ r = rbd_open(s->io_ctx, s->name, &s->image, s->snap);
+ if (r < 0) {
+ error_setg(errp, "error reading header from %s", s->name);
+ goto failed_open;
+ }
+
+ bs->read_only = (s->snap != NULL);
+
+ qemu_opts_del(opts);
+ return 0;
+
+failed_open:
+ rados_ioctx_destroy(s->io_ctx);
+failed_shutdown:
+ rados_shutdown(s->cluster);
+ g_free(s->snap);
+failed_opts:
+ qemu_opts_del(opts);
+ return r;
+}
+
+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);
+ rados_shutdown(s->cluster);
+}
+
+static const AIOCBInfo rbd_aiocb_info = {
+ .aiocb_size = sizeof(RBDAIOCB),
+};
+
+static void rbd_finish_bh(void *opaque)
+{
+ RADOSCB *rcb = opaque;
+ qemu_bh_delete(rcb->acb->bh);
+ qemu_rbd_complete_aio(rcb);
+}
+
+/*
+ * This is the callback function for rbd_aio_read and _write
+ *
+ * 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 rbd_finish_bh() which runs in a qemu context.
+ */
+static void rbd_finish_aiocb(rbd_completion_t c, RADOSCB *rcb)
+{
+ RBDAIOCB *acb = rcb->acb;
+
+ rcb->ret = rbd_aio_get_return_value(c);
+ rbd_aio_release(c);
+
+ acb->bh = aio_bh_new(bdrv_get_aio_context(acb->common.bs),
+ rbd_finish_bh, rcb);
+ qemu_bh_schedule(acb->bh);
+}
+
+static int rbd_aio_discard_wrapper(rbd_image_t image,
+ uint64_t off,
+ uint64_t len,
+ rbd_completion_t comp)
+{
+#ifdef LIBRBD_SUPPORTS_DISCARD
+ return rbd_aio_discard(image, off, len, comp);
+#else
+ return -ENOTSUP;
+#endif
+}
+
+static int rbd_aio_flush_wrapper(rbd_image_t image,
+ rbd_completion_t comp)
+{
+#ifdef LIBRBD_SUPPORTS_AIO_FLUSH
+ return rbd_aio_flush(image, comp);
+#else
+ return -ENOTSUP;
+#endif
+}
+
+static BlockAIOCB *rbd_start_aio(BlockDriverState *bs,
+ int64_t sector_num,
+ QEMUIOVector *qiov,
+ int nb_sectors,
+ BlockCompletionFunc *cb,
+ void *opaque,
+ RBDAIOCmd cmd)
+{
+ RBDAIOCB *acb;
+ RADOSCB *rcb = NULL;
+ rbd_completion_t c;
+ int64_t off, size;
+ char *buf;
+ int r;
+
+ BDRVRBDState *s = bs->opaque;
+
+ acb = qemu_aio_get(&rbd_aiocb_info, bs, cb, opaque);
+ acb->cmd = cmd;
+ acb->qiov = qiov;
+ if (cmd == RBD_AIO_DISCARD || cmd == RBD_AIO_FLUSH) {
+ acb->bounce = NULL;
+ } else {
+ acb->bounce = qemu_try_blockalign(bs, qiov->size);
+ if (acb->bounce == NULL) {
+ goto failed;
+ }
+ }
+ acb->ret = 0;
+ acb->error = 0;
+ acb->s = s;
+ acb->bh = NULL;
+
+ if (cmd == RBD_AIO_WRITE) {
+ qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size);
+ }
+
+ buf = acb->bounce;
+
+ off = sector_num * BDRV_SECTOR_SIZE;
+ size = nb_sectors * BDRV_SECTOR_SIZE;
+
+ rcb = g_new(RADOSCB, 1);
+ rcb->acb = acb;
+ rcb->buf = buf;
+ rcb->s = acb->s;
+ rcb->size = size;
+ r = rbd_aio_create_completion(rcb, (rbd_callback_t) rbd_finish_aiocb, &c);
+ if (r < 0) {
+ goto failed;
+ }
+
+ switch (cmd) {
+ case RBD_AIO_WRITE:
+ r = rbd_aio_write(s->image, off, size, buf, c);
+ break;
+ case RBD_AIO_READ:
+ r = rbd_aio_read(s->image, off, size, buf, c);
+ break;
+ case RBD_AIO_DISCARD:
+ r = rbd_aio_discard_wrapper(s->image, off, size, c);
+ break;
+ case RBD_AIO_FLUSH:
+ r = rbd_aio_flush_wrapper(s->image, c);
+ break;
+ default:
+ r = -EINVAL;
+ }
+
+ if (r < 0) {
+ goto failed_completion;
+ }
+
+ return &acb->common;
+
+failed_completion:
+ rbd_aio_release(c);
+failed:
+ g_free(rcb);
+ qemu_vfree(acb->bounce);
+ qemu_aio_unref(acb);
+ return NULL;
+}
+
+static BlockAIOCB *qemu_rbd_aio_readv(BlockDriverState *bs,
+ int64_t sector_num,
+ QEMUIOVector *qiov,
+ int nb_sectors,
+ BlockCompletionFunc *cb,
+ void *opaque)
+{
+ return rbd_start_aio(bs, sector_num, qiov, nb_sectors, cb, opaque,
+ RBD_AIO_READ);
+}
+
+static BlockAIOCB *qemu_rbd_aio_writev(BlockDriverState *bs,
+ int64_t sector_num,
+ QEMUIOVector *qiov,
+ int nb_sectors,
+ BlockCompletionFunc *cb,
+ void *opaque)
+{
+ return rbd_start_aio(bs, sector_num, qiov, nb_sectors, cb, opaque,
+ RBD_AIO_WRITE);
+}
+
+#ifdef LIBRBD_SUPPORTS_AIO_FLUSH
+static BlockAIOCB *qemu_rbd_aio_flush(BlockDriverState *bs,
+ BlockCompletionFunc *cb,
+ void *opaque)
+{
+ return rbd_start_aio(bs, 0, NULL, 0, cb, opaque, RBD_AIO_FLUSH);
+}
+
+#else
+
+static int qemu_rbd_co_flush(BlockDriverState *bs)
+{
+#if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 1)
+ /* rbd_flush added in 0.1.1 */
+ BDRVRBDState *s = bs->opaque;
+ return rbd_flush(s->image);
+#else
+ return 0;
+#endif
+}
+#endif
+
+static int qemu_rbd_getinfo(BlockDriverState *bs, BlockDriverInfo *bdi)
+{
+ BDRVRBDState *s = bs->opaque;
+ rbd_image_info_t info;
+ int r;
+
+ r = rbd_stat(s->image, &info, sizeof(info));
+ if (r < 0) {
+ return r;
+ }
+
+ bdi->cluster_size = info.obj_size;
+ return 0;
+}
+
+static int64_t qemu_rbd_getlength(BlockDriverState *bs)
+{
+ BDRVRBDState *s = bs->opaque;
+ rbd_image_info_t info;
+ int r;
+
+ r = rbd_stat(s->image, &info, sizeof(info));
+ if (r < 0) {
+ return r;
+ }
+
+ return info.size;
+}
+
+static int qemu_rbd_truncate(BlockDriverState *bs, int64_t offset)
+{
+ BDRVRBDState *s = bs->opaque;
+ int r;
+
+ r = rbd_resize(s->image, offset);
+ if (r < 0) {
+ 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;
+ int r;
+
+ r = rbd_snap_rollback(s->image, snapshot_name);
+ return r;
+}
+
+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;
+}
+
+#ifdef LIBRBD_SUPPORTS_DISCARD
+static BlockAIOCB* qemu_rbd_aio_discard(BlockDriverState *bs,
+ int64_t sector_num,
+ int nb_sectors,
+ BlockCompletionFunc *cb,
+ void *opaque)
+{
+ return rbd_start_aio(bs, sector_num, NULL, nb_sectors, cb, opaque,
+ RBD_AIO_DISCARD);
+}
+#endif
+
+#ifdef LIBRBD_SUPPORTS_INVALIDATE
+static void qemu_rbd_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");
+ }
+}
+#endif
+
+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"
+ },
+ { /* end of list */ }
+ }
+};
+
+static BlockDriver bdrv_rbd = {
+ .format_name = "rbd",
+ .instance_size = sizeof(BDRVRBDState),
+ .bdrv_needs_filename = true,
+ .bdrv_file_open = qemu_rbd_open,
+ .bdrv_close = qemu_rbd_close,
+ .bdrv_create = qemu_rbd_create,
+ .bdrv_has_zero_init = bdrv_has_zero_init_1,
+ .bdrv_get_info = qemu_rbd_getinfo,
+ .create_opts = &qemu_rbd_create_opts,
+ .bdrv_getlength = qemu_rbd_getlength,
+ .bdrv_truncate = qemu_rbd_truncate,
+ .protocol_name = "rbd",
+
+ .bdrv_aio_readv = qemu_rbd_aio_readv,
+ .bdrv_aio_writev = qemu_rbd_aio_writev,
+
+#ifdef LIBRBD_SUPPORTS_AIO_FLUSH
+ .bdrv_aio_flush = qemu_rbd_aio_flush,
+#else
+ .bdrv_co_flush_to_disk = qemu_rbd_co_flush,
+#endif
+
+#ifdef LIBRBD_SUPPORTS_DISCARD
+ .bdrv_aio_discard = qemu_rbd_aio_discard,
+#endif
+
+ .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,
+#ifdef LIBRBD_SUPPORTS_INVALIDATE
+ .bdrv_invalidate_cache = qemu_rbd_invalidate_cache,
+#endif
+};
+
+static void bdrv_rbd_init(void)
+{
+ bdrv_register(&bdrv_rbd);
+}
+
+block_init(bdrv_rbd_init);
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