From: Vasiliy Tolstov <v.tols...@selfip.ru>
This patch implements a blockdriver function bdrv_snapshot_delete() in
the sheepdog driver. With the new function, snapshots of sheepdog can
be deleted from libvirt.
Cc: Jeff Cody <jc...@redhat.com>
Signed-off-by: Hitoshi Mitake <mitake.hito...@lab.ntt.co.jp>
Signed-off-by: Vasiliy Tolstov <v.tols...@selfip.ru>
Message-id: 1450873346-22334-1-git-send-email-mitake.hito...@lab.ntt.co.jp
Signed-off-by: Jeff Cody <jc...@redhat.com>
---
block/sheepdog.c | 125 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 123 insertions(+), 2 deletions(-)
diff --git a/block/sheepdog.c b/block/sheepdog.c
index a0098c1..8739acc 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -284,6 +284,12 @@ static inline bool is_snapshot(struct SheepdogInode *inode)
return !!inode->snap_ctime;
}
+static inline size_t count_data_objs(const struct SheepdogInode *inode)
+{
+ return DIV_ROUND_UP(inode->vdi_size,
+ (1UL << inode->block_size_shift));
+}
+
#undef DPRINTF
#ifdef DEBUG_SDOG
#define DPRINTF(fmt, args...) \
@@ -2478,13 +2484,128 @@ out:
return ret;
}
+#define NR_BATCHED_DISCARD 128
+
+static bool remove_objects(BDRVSheepdogState *s)
+{
+ int fd, i = 0, nr_objs = 0;
+ Error *local_err = NULL;
+ int ret = 0;
+ bool result = true;
+ SheepdogInode *inode = &s->inode;
+
+ fd = connect_to_sdog(s, &local_err);
+ if (fd < 0) {
+ error_report_err(local_err);
+ return false;
+ }
+
+ nr_objs = count_data_objs(inode);
+ while (i < nr_objs) {
+ int start_idx, nr_filled_idx;
+
+ while (i < nr_objs && !inode->data_vdi_id[i]) {
+ i++;
+ }
+ start_idx = i;
+
+ nr_filled_idx = 0;
+ while (i < nr_objs && nr_filled_idx < NR_BATCHED_DISCARD) {
+ if (inode->data_vdi_id[i]) {
+ inode->data_vdi_id[i] = 0;
+ nr_filled_idx++;
+ }
+
+ i++;
+ }
+
+ ret = write_object(fd, s->aio_context,
+ (char *)&inode->data_vdi_id[start_idx],
+ vid_to_vdi_oid(s->inode.vdi_id), inode->nr_copies,
+ (i - start_idx) * sizeof(uint32_t),
+ offsetof(struct SheepdogInode,
+ data_vdi_id[start_idx]),
+ false, s->cache_flags);
+ if (ret < 0) {
+ error_report("failed to discard snapshot inode.");
+ result = false;
+ goto out;
+ }
+ }
+
+out:
+ closesocket(fd);
+ return result;
+}
+
static int sd_snapshot_delete(BlockDriverState *bs,
const char *snapshot_id,
const char *name,
Error **errp)
{
- /* FIXME: Delete specified snapshot id. */
- return 0;
+ uint32_t snap_id = 0;
+ char snap_tag[SD_MAX_VDI_TAG_LEN];
+ Error *local_err = NULL;
+ int fd, ret;
+ char buf[SD_MAX_VDI_LEN + SD_MAX_VDI_TAG_LEN];
+ BDRVSheepdogState *s = bs->opaque;
+ unsigned int wlen = SD_MAX_VDI_LEN + SD_MAX_VDI_TAG_LEN, rlen = 0;
+ uint32_t vid;
+ SheepdogVdiReq hdr = {
+ .opcode = SD_OP_DEL_VDI,
+ .data_length = wlen,
+ .flags = SD_FLAG_CMD_WRITE,
+ };
+ SheepdogVdiRsp *rsp = (SheepdogVdiRsp *)&hdr;
+
+ if (!remove_objects(s)) {
+ return -1;
+ }
+
+ memset(buf, 0, sizeof(buf));
+ memset(snap_tag, 0, sizeof(snap_tag));
+ pstrcpy(buf, SD_MAX_VDI_LEN, s->name);
+ if (qemu_strtoul(snapshot_id, NULL, 10, (unsigned long *)&snap_id)) {
+ return -1;
+ }
+
+ if (snap_id) {
+ hdr.snapid = snap_id;
+ } else {
+ pstrcpy(snap_tag, sizeof(snap_tag), snapshot_id);
+ pstrcpy(buf + SD_MAX_VDI_LEN, SD_MAX_VDI_TAG_LEN, snap_tag);
+ }
+
+ ret = find_vdi_name(s, s->name, snap_id, snap_tag, &vid, true,
+ &local_err);
+ if (ret) {
+ return ret;
+ }
+
+ fd = connect_to_sdog(s, &local_err);
+ if (fd < 0) {
+ error_report_err(local_err);
+ return -1;
+ }
+
+ ret = do_req(fd, s->aio_context, (SheepdogReq *)&hdr,
+ buf, &wlen, &rlen);
+ closesocket(fd);
+ if (ret) {
+ return ret;
+ }
+
+ switch (rsp->result) {
+ case SD_RES_NO_VDI:
+ error_report("%s was already deleted", s->name);
+ case SD_RES_SUCCESS:
+ break;
+ default:
+ error_report("%s, %s", sd_strerror(rsp->result), s->name);
+ return -1;
+ }
+
+ return ret;
}
static int sd_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab)
--
1.9.3
