#define SD_OP_CREATE_AND_WRITE_OBJ 0x01
#define SD_OP_READ_OBJ 0x02
#define SD_OP_WRITE_OBJ 0x03
+/* 0x04 is used internally by Sheepdog */
+#define SD_OP_DISCARD_OBJ 0x05
#define SD_OP_NEW_VDI 0x11
#define SD_OP_LOCK_VDI 0x12
#define SD_OP_GET_VDI_INFO 0x14
#define SD_OP_READ_VDIS 0x15
#define SD_OP_FLUSH_VDI 0x16
+#define SD_OP_DEL_VDI 0x17
#define SD_FLAG_CMD_WRITE 0x01
#define SD_FLAG_CMD_COW 0x02
#define SD_RES_WAIT_FOR_FORMAT 0x16 /* Waiting for a format operation */
#define SD_RES_WAIT_FOR_JOIN 0x17 /* Waiting for other nodes joining */
#define SD_RES_JOIN_FAILED 0x18 /* Target node had failed to join sheepdog */
+#define SD_RES_HALT 0x19 /* Sheepdog is stopped serving IO request */
+#define SD_RES_READONLY 0x1A /* Object is read-only */
/*
* Object ID rules
#define SD_NR_VDIS (1U << 24)
#define SD_DATA_OBJ_SIZE (UINT64_C(1) << 22)
#define SD_MAX_VDI_SIZE (SD_DATA_OBJ_SIZE * MAX_DATA_OBJS)
-#define SECTOR_SIZE 512
#define SD_INODE_SIZE (sizeof(SheepdogInode))
#define CURRENT_VDI_ID 0
AIOCB_WRITE_UDATA,
AIOCB_READ_UDATA,
AIOCB_FLUSH_CACHE,
+ AIOCB_DISCARD_OBJ,
};
struct SheepdogAIOCB {
char name[SD_MAX_VDI_LEN];
bool is_snapshot;
uint32_t cache_flags;
+ bool discard_supported;
char *host_spec;
bool is_unix;
{SD_RES_WAIT_FOR_FORMAT, "Sheepdog is waiting for a format operation"},
{SD_RES_WAIT_FOR_JOIN, "Sheepdog is waiting for other nodes joining"},
{SD_RES_JOIN_FAILED, "Target node had failed to join sheepdog"},
+ {SD_RES_HALT, "Sheepdog is stopped serving IO request"},
+ {SD_RES_READONLY, "Object is read-only"},
};
for (i = 0; i < ARRAY_SIZE(errors); ++i) {
if (err != NULL) {
qerror_report_err(err);
error_free(err);
+ } else {
+ qemu_set_nonblock(fd);
}
return fd;
qemu_coroutine_enter(co, NULL);
}
+static int have_co_req(void *opaque)
+{
+ /* this handler is set only when there is a pending request, so
+ * always returns 1. */
+ return 1;
+}
+
typedef struct SheepdogReqCo {
int sockfd;
SheepdogReq *hdr;
unsigned int *rlen = srco->rlen;
co = qemu_coroutine_self();
- qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, NULL, co);
+ qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, have_co_req, co);
- socket_set_block(sockfd);
ret = send_co_req(sockfd, hdr, data, wlen);
if (ret < 0) {
goto out;
}
- qemu_aio_set_fd_handler(sockfd, restart_co_req, NULL, NULL, co);
+ qemu_aio_set_fd_handler(sockfd, restart_co_req, NULL, have_co_req, co);
ret = qemu_co_recv(sockfd, hdr, sizeof(*hdr));
if (ret < sizeof(*hdr)) {
}
ret = 0;
out:
+ /* there is at most one request for this sockfd, so it is safe to
+ * set each handler to NULL. */
qemu_aio_set_fd_handler(sockfd, NULL, NULL, NULL, NULL);
- socket_set_nonblock(sockfd);
srco->ret = ret;
srco->finished = true;
static int coroutine_fn add_aio_request(BDRVSheepdogState *s, AIOReq *aio_req,
struct iovec *iov, int niov, bool create,
enum AIOCBState aiocb_type);
+static int coroutine_fn resend_aioreq(BDRVSheepdogState *s, AIOReq *aio_req);
static AIOReq *find_pending_req(BDRVSheepdogState *s, uint64_t oid)
int ret;
AIOReq *aio_req = NULL;
SheepdogAIOCB *acb;
- unsigned long idx;
+ uint64_t idx;
if (QLIST_EMPTY(&s->inflight_aio_head)) {
goto out;
rsp.result = SD_RES_SUCCESS;
}
break;
+ case AIOCB_DISCARD_OBJ:
+ switch (rsp.result) {
+ case SD_RES_INVALID_PARMS:
+ error_report("sheep(%s) doesn't support discard command",
+ s->host_spec);
+ rsp.result = SD_RES_SUCCESS;
+ s->discard_supported = false;
+ break;
+ case SD_RES_SUCCESS:
+ idx = data_oid_to_idx(aio_req->oid);
+ s->inode.data_vdi_id[idx] = 0;
+ break;
+ default:
+ break;
+ }
}
- if (rsp.result != SD_RES_SUCCESS) {
+ switch (rsp.result) {
+ case SD_RES_SUCCESS:
+ break;
+ case SD_RES_READONLY:
+ ret = resend_aioreq(s, aio_req);
+ if (ret == SD_RES_SUCCESS) {
+ goto out;
+ }
+ /* fall through */
+ default:
acb->ret = -EIO;
error_report("%s", sd_strerror(rsp.result));
+ break;
}
free_aio_req(s, aio_req);
return fd;
}
- socket_set_nonblock(fd);
-
qemu_aio_set_fd_handler(fd, co_read_response, NULL, aio_flush_request, s);
return fd;
}
return ret;
}
-static int find_vdi_name(BDRVSheepdogState *s, char *filename, uint32_t snapid,
- char *tag, uint32_t *vid, int for_snapshot)
+static int find_vdi_name(BDRVSheepdogState *s, const char *filename,
+ uint32_t snapid, const char *tag, uint32_t *vid,
+ bool lock)
{
int ret, fd;
SheepdogVdiReq hdr;
strncpy(buf + SD_MAX_VDI_LEN, tag, SD_MAX_VDI_TAG_LEN);
memset(&hdr, 0, sizeof(hdr));
- if (for_snapshot) {
- hdr.opcode = SD_OP_GET_VDI_INFO;
- } else {
+ if (lock) {
hdr.opcode = SD_OP_LOCK_VDI;
+ } else {
+ hdr.opcode = SD_OP_GET_VDI_INFO;
}
wlen = SD_MAX_VDI_LEN + SD_MAX_VDI_TAG_LEN;
hdr.proto_ver = SD_PROTO_VER;
wlen = datalen;
hdr.flags = SD_FLAG_CMD_WRITE | flags;
break;
+ case AIOCB_DISCARD_OBJ:
+ hdr.opcode = SD_OP_DISCARD_OBJ;
+ break;
}
if (s->cache_flags) {
create, cache_flags);
}
-static int sd_open(BlockDriverState *bs, const char *filename, int flags)
+/* update inode with the latest state */
+static int reload_inode(BDRVSheepdogState *s, uint32_t snapid, const char *tag)
+{
+ SheepdogInode *inode;
+ int ret = 0, fd;
+ uint32_t vid = 0;
+
+ fd = connect_to_sdog(s);
+ if (fd < 0) {
+ return -EIO;
+ }
+
+ inode = g_malloc(sizeof(s->inode));
+
+ ret = find_vdi_name(s, s->name, snapid, tag, &vid, false);
+ if (ret) {
+ goto out;
+ }
+
+ ret = read_object(fd, (char *)inode, vid_to_vdi_oid(vid),
+ s->inode.nr_copies, sizeof(*inode), 0, s->cache_flags);
+ if (ret < 0) {
+ goto out;
+ }
+
+ if (inode->vdi_id != s->inode.vdi_id) {
+ memcpy(&s->inode, inode, sizeof(s->inode));
+ }
+
+out:
+ g_free(inode);
+ closesocket(fd);
+
+ return ret;
+}
+
+static int coroutine_fn resend_aioreq(BDRVSheepdogState *s, AIOReq *aio_req)
+{
+ SheepdogAIOCB *acb = aio_req->aiocb;
+ bool create = false;
+ int ret;
+
+ ret = reload_inode(s, 0, "");
+ if (ret < 0) {
+ return ret;
+ }
+
+ aio_req->oid = vid_to_data_oid(s->inode.vdi_id,
+ data_oid_to_idx(aio_req->oid));
+
+ /* check whether this request becomes a CoW one */
+ if (acb->aiocb_type == AIOCB_WRITE_UDATA) {
+ int idx = data_oid_to_idx(aio_req->oid);
+ AIOReq *areq;
+
+ if (s->inode.data_vdi_id[idx] == 0) {
+ create = true;
+ goto out;
+ }
+ if (is_data_obj_writable(&s->inode, idx)) {
+ goto out;
+ }
+
+ /* link to the pending list if there is another CoW request to
+ * the same object */
+ QLIST_FOREACH(areq, &s->inflight_aio_head, aio_siblings) {
+ if (areq != aio_req && areq->oid == aio_req->oid) {
+ dprintf("simultaneous CoW to %" PRIx64 "\n", aio_req->oid);
+ QLIST_REMOVE(aio_req, aio_siblings);
+ QLIST_INSERT_HEAD(&s->pending_aio_head, aio_req, aio_siblings);
+ return SD_RES_SUCCESS;
+ }
+ }
+
+ aio_req->base_oid = vid_to_data_oid(s->inode.data_vdi_id[idx], idx);
+ aio_req->flags |= SD_FLAG_CMD_COW;
+ create = true;
+ }
+out:
+ return add_aio_request(s, aio_req, acb->qiov->iov, acb->qiov->niov,
+ create, acb->aiocb_type);
+}
+
+/* TODO Convert to fine grained options */
+static QemuOptsList runtime_opts = {
+ .name = "sheepdog",
+ .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
+ .desc = {
+ {
+ .name = "filename",
+ .type = QEMU_OPT_STRING,
+ .help = "URL to the sheepdog image",
+ },
+ { /* end of list */ }
+ },
+};
+
+static int sd_open(BlockDriverState *bs, QDict *options, int flags)
{
int ret, fd;
uint32_t vid = 0;
char vdi[SD_MAX_VDI_LEN], tag[SD_MAX_VDI_TAG_LEN];
uint32_t snapid;
char *buf = NULL;
+ QemuOpts *opts;
+ Error *local_err = NULL;
+ const char *filename;
+
+ opts = qemu_opts_create_nofail(&runtime_opts);
+ qemu_opts_absorb_qdict(opts, options, &local_err);
+ if (error_is_set(&local_err)) {
+ qerror_report_err(local_err);
+ error_free(local_err);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ filename = qemu_opt_get(opts, "filename");
QLIST_INIT(&s->inflight_aio_head);
QLIST_INIT(&s->pending_aio_head);
goto out;
}
- ret = find_vdi_name(s, vdi, snapid, tag, &vid, 0);
+ ret = find_vdi_name(s, vdi, snapid, tag, &vid, true);
if (ret) {
goto out;
}
if (flags & BDRV_O_NOCACHE) {
s->cache_flags = SD_FLAG_CMD_DIRECT;
}
+ s->discard_supported = true;
if (snapid || tag[0] != '\0') {
dprintf("%" PRIx32 " snapshot inode was open.\n", vid);
s->min_dirty_data_idx = UINT32_MAX;
s->max_dirty_data_idx = 0;
- bs->total_sectors = s->inode.vdi_size / SECTOR_SIZE;
+ bs->total_sectors = s->inode.vdi_size / BDRV_SECTOR_SIZE;
pstrcpy(s->name, sizeof(s->name), vdi);
qemu_co_mutex_init(&s->lock);
+ qemu_opts_del(opts);
g_free(buf);
return 0;
out:
if (s->fd >= 0) {
closesocket(s->fd);
}
+ qemu_opts_del(opts);
g_free(buf);
return ret;
}
void *buf = g_malloc0(SD_DATA_OBJ_SIZE);
int ret;
- ret = bdrv_file_open(&bs, filename, BDRV_O_RDWR);
+ ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR);
if (ret < 0) {
goto out;
}
goto out;
}
- ret = bdrv_file_open(&bs, backing_file, 0);
+ ret = bdrv_file_open(&bs, backing_file, NULL, 0);
if (ret < 0) {
goto out;
}
sd_finish_aiocb(acb);
}
+/* Delete current working VDI on the snapshot chain */
+static bool sd_delete(BDRVSheepdogState *s)
+{
+ unsigned int wlen = SD_MAX_VDI_LEN, rlen = 0;
+ SheepdogVdiReq hdr = {
+ .opcode = SD_OP_DEL_VDI,
+ .vdi_id = s->inode.vdi_id,
+ .data_length = wlen,
+ .flags = SD_FLAG_CMD_WRITE,
+ };
+ SheepdogVdiRsp *rsp = (SheepdogVdiRsp *)&hdr;
+ int fd, ret;
+
+ fd = connect_to_sdog(s);
+ if (fd < 0) {
+ return false;
+ }
+
+ ret = do_req(fd, (SheepdogReq *)&hdr, s->name, &wlen, &rlen);
+ closesocket(fd);
+ if (ret) {
+ return false;
+ }
+ switch (rsp->result) {
+ case SD_RES_NO_VDI:
+ error_report("%s was already deleted", s->name);
+ /* fall through */
+ case SD_RES_SUCCESS:
+ break;
+ default:
+ error_report("%s, %s", sd_strerror(rsp->result), s->name);
+ return false;
+ }
+
+ return true;
+}
+
/*
* Create a writable VDI from a snapshot
*/
int ret, fd;
uint32_t vid;
char *buf;
+ bool deleted;
dprintf("%" PRIx32 " is snapshot.\n", s->inode.vdi_id);
buf = g_malloc(SD_INODE_SIZE);
- ret = do_sd_create(s, s->name, s->inode.vdi_size, s->inode.vdi_id, &vid, 1);
+ /*
+ * Even If deletion fails, we will just create extra snapshot based on
+ * the workding VDI which was supposed to be deleted. So no need to
+ * false bail out.
+ */
+ deleted = sd_delete(s);
+ ret = do_sd_create(s, s->name, s->inode.vdi_size, s->inode.vdi_id, &vid,
+ !deleted);
if (ret) {
goto out;
}
{
SheepdogAIOCB *acb = p;
int ret = 0;
- unsigned long len, done = 0, total = acb->nb_sectors * SECTOR_SIZE;
- unsigned long idx = acb->sector_num * SECTOR_SIZE / SD_DATA_OBJ_SIZE;
+ unsigned long len, done = 0, total = acb->nb_sectors * BDRV_SECTOR_SIZE;
+ unsigned long idx = acb->sector_num * BDRV_SECTOR_SIZE / SD_DATA_OBJ_SIZE;
uint64_t oid;
- uint64_t offset = (acb->sector_num * SECTOR_SIZE) % SD_DATA_OBJ_SIZE;
+ uint64_t offset = (acb->sector_num * BDRV_SECTOR_SIZE) % SD_DATA_OBJ_SIZE;
BDRVSheepdogState *s = acb->common.bs->opaque;
SheepdogInode *inode = &s->inode;
AIOReq *aio_req;
flags = SD_FLAG_CMD_COW;
}
break;
+ case AIOCB_DISCARD_OBJ:
+ /*
+ * We discard the object only when the whole object is
+ * 1) allocated 2) trimmed. Otherwise, simply skip it.
+ */
+ if (len != SD_DATA_OBJ_SIZE || inode->data_vdi_id[idx] == 0) {
+ goto done;
+ }
+ break;
default:
break;
}
int ret;
if (bs->growable && sector_num + nb_sectors > bs->total_sectors) {
- ret = sd_truncate(bs, (sector_num + nb_sectors) * SECTOR_SIZE);
+ ret = sd_truncate(bs, (sector_num + nb_sectors) * BDRV_SECTOR_SIZE);
if (ret < 0) {
return ret;
}
return ret;
}
+/*
+ * We implement rollback(loadvm) operation to the specified snapshot by
+ * 1) switch to the snapshot
+ * 2) rely on sd_create_branch to delete working VDI and
+ * 3) create a new working VDI based on the speicified snapshot
+ */
static int sd_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
{
BDRVSheepdogState *s = bs->opaque;
BDRVSheepdogState *old_s;
- char vdi[SD_MAX_VDI_LEN], tag[SD_MAX_VDI_TAG_LEN];
- char *buf = NULL;
- uint32_t vid;
+ char tag[SD_MAX_VDI_TAG_LEN];
uint32_t snapid = 0;
- int ret = 0, fd;
+ int ret = 0;
old_s = g_malloc(sizeof(BDRVSheepdogState));
memcpy(old_s, s, sizeof(BDRVSheepdogState));
- pstrcpy(vdi, sizeof(vdi), s->name);
-
snapid = strtoul(snapshot_id, NULL, 10);
if (snapid) {
tag[0] = 0;
} else {
- pstrcpy(tag, sizeof(tag), s->name);
+ pstrcpy(tag, sizeof(tag), snapshot_id);
}
- ret = find_vdi_name(s, vdi, snapid, tag, &vid, 1);
+ ret = reload_inode(s, snapid, tag);
if (ret) {
- error_report("Failed to find_vdi_name");
- goto out;
- }
-
- fd = connect_to_sdog(s);
- if (fd < 0) {
- ret = fd;
goto out;
}
- buf = g_malloc(SD_INODE_SIZE);
- ret = read_object(fd, buf, vid_to_vdi_oid(vid), s->inode.nr_copies,
- SD_INODE_SIZE, 0, s->cache_flags);
-
- closesocket(fd);
-
+ ret = sd_create_branch(s);
if (ret) {
goto out;
}
- memcpy(&s->inode, buf, sizeof(s->inode));
-
- if (!s->inode.vm_state_size) {
- error_report("Invalid snapshot");
- ret = -ENOENT;
- goto out;
- }
-
- s->is_snapshot = true;
-
- g_free(buf);
g_free(old_s);
return 0;
out:
/* recover bdrv_sd_state */
memcpy(s, old_s, sizeof(BDRVSheepdogState));
- g_free(buf);
g_free(old_s);
error_report("failed to open. recover old bdrv_sd_state.");
int fd, ret = 0, remaining = size;
unsigned int data_len;
uint64_t vmstate_oid;
- uint32_t vdi_index;
uint64_t offset;
+ uint32_t vdi_index;
+ uint32_t vdi_id = load ? s->inode.parent_vdi_id : s->inode.vdi_id;
fd = connect_to_sdog(s);
if (fd < 0) {
data_len = MIN(remaining, SD_DATA_OBJ_SIZE - offset);
- vmstate_oid = vid_to_vmstate_oid(s->inode.vdi_id, vdi_index);
+ vmstate_oid = vid_to_vmstate_oid(vdi_id, vdi_index);
create = (offset == 0);
if (load) {
return ret;
}
-static int sd_save_vmstate(BlockDriverState *bs, const uint8_t *data,
- int64_t pos, int size)
+static int sd_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov,
+ int64_t pos)
{
BDRVSheepdogState *s = bs->opaque;
+ void *buf;
+ int ret;
+
+ buf = qemu_blockalign(bs, qiov->size);
+ qemu_iovec_to_buf(qiov, 0, buf, qiov->size);
+ ret = do_load_save_vmstate(s, (uint8_t *) buf, pos, qiov->size, 0);
+ qemu_vfree(buf);
- return do_load_save_vmstate(s, (uint8_t *)data, pos, size, 0);
+ return ret;
}
static int sd_load_vmstate(BlockDriverState *bs, uint8_t *data,
}
+static coroutine_fn int sd_co_discard(BlockDriverState *bs, int64_t sector_num,
+ int nb_sectors)
+{
+ SheepdogAIOCB *acb;
+ QEMUIOVector dummy;
+ BDRVSheepdogState *s = bs->opaque;
+ int ret;
+
+ if (!s->discard_supported) {
+ return 0;
+ }
+
+ acb = sd_aio_setup(bs, &dummy, sector_num, nb_sectors);
+ acb->aiocb_type = AIOCB_DISCARD_OBJ;
+ acb->aio_done_func = sd_finish_aiocb;
+
+ ret = sd_co_rw_vector(acb);
+ if (ret <= 0) {
+ qemu_aio_release(acb);
+ return ret;
+ }
+
+ qemu_coroutine_yield();
+
+ return acb->ret;
+}
+
+static coroutine_fn int
+sd_co_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
+ int *pnum)
+{
+ BDRVSheepdogState *s = bs->opaque;
+ SheepdogInode *inode = &s->inode;
+ unsigned long start = sector_num * BDRV_SECTOR_SIZE / SD_DATA_OBJ_SIZE,
+ end = DIV_ROUND_UP((sector_num + nb_sectors) *
+ BDRV_SECTOR_SIZE, SD_DATA_OBJ_SIZE);
+ unsigned long idx;
+ int ret = 1;
+
+ for (idx = start; idx < end; idx++) {
+ if (inode->data_vdi_id[idx] == 0) {
+ break;
+ }
+ }
+ if (idx == start) {
+ /* Get the longest length of unallocated sectors */
+ ret = 0;
+ for (idx = start + 1; idx < end; idx++) {
+ if (inode->data_vdi_id[idx] != 0) {
+ break;
+ }
+ }
+ }
+
+ *pnum = (idx - start) * SD_DATA_OBJ_SIZE / BDRV_SECTOR_SIZE;
+ if (*pnum > nb_sectors) {
+ *pnum = nb_sectors;
+ }
+ return ret;
+}
+
static QEMUOptionParameter sd_create_options[] = {
{
.name = BLOCK_OPT_SIZE,
.bdrv_co_readv = sd_co_readv,
.bdrv_co_writev = sd_co_writev,
.bdrv_co_flush_to_disk = sd_co_flush_to_disk,
+ .bdrv_co_discard = sd_co_discard,
+ .bdrv_co_is_allocated = sd_co_is_allocated,
.bdrv_snapshot_create = sd_snapshot_create,
.bdrv_snapshot_goto = sd_snapshot_goto,
.bdrv_co_readv = sd_co_readv,
.bdrv_co_writev = sd_co_writev,
.bdrv_co_flush_to_disk = sd_co_flush_to_disk,
+ .bdrv_co_discard = sd_co_discard,
+ .bdrv_co_is_allocated = sd_co_is_allocated,
.bdrv_snapshot_create = sd_snapshot_create,
.bdrv_snapshot_goto = sd_snapshot_goto,
.bdrv_co_readv = sd_co_readv,
.bdrv_co_writev = sd_co_writev,
.bdrv_co_flush_to_disk = sd_co_flush_to_disk,
+ .bdrv_co_discard = sd_co_discard,
+ .bdrv_co_is_allocated = sd_co_is_allocated,
.bdrv_snapshot_create = sd_snapshot_create,
.bdrv_snapshot_goto = sd_snapshot_goto,