diff options
Diffstat (limited to 'drivers/md/dm-snap.c')
| -rw-r--r-- | drivers/md/dm-snap.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 87727d84dbb..f3759dd7828 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -373,16 +373,11 @@ static inline ulong round_up(ulong n, ulong size) static void read_snapshot_metadata(struct dm_snapshot *s) { - if (s->have_metadata) - return; - if (s->store.read_metadata(&s->store)) { down_write(&s->lock); s->valid = 0; up_write(&s->lock); } - - s->have_metadata = 1; } /* @@ -471,7 +466,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) s->chunk_shift = ffs(chunk_size) - 1; s->valid = 1; - s->have_metadata = 0; + s->active = 0; s->last_percent = 0; init_rwsem(&s->lock); s->table = ti->table; @@ -506,7 +501,11 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv) goto bad5; } + /* Metadata must only be loaded into one table at once */ + read_snapshot_metadata(s); + /* Add snapshot to the list of snapshots for this origin */ + /* Exceptions aren't triggered till snapshot_resume() is called */ if (register_snapshot(s)) { r = -EINVAL; ti->error = "Cannot register snapshot origin"; @@ -793,6 +792,9 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio, if (!s->valid) return -EIO; + if (unlikely(bio_barrier(bio))) + return -EOPNOTSUPP; + /* * Write to snapshot - higher level takes care of RW/RO * flags so we should only get this if we are @@ -862,7 +864,9 @@ static void snapshot_resume(struct dm_target *ti) { struct dm_snapshot *s = (struct dm_snapshot *) ti->private; - read_snapshot_metadata(s); + down_write(&s->lock); + s->active = 1; + up_write(&s->lock); } static int snapshot_status(struct dm_target *ti, status_type_t type, @@ -932,8 +936,8 @@ static int __origin_write(struct list_head *snapshots, struct bio *bio) /* Do all the snapshots on this origin */ list_for_each_entry (snap, snapshots, list) { - /* Only deal with valid snapshots */ - if (!snap->valid) + /* Only deal with valid and active snapshots */ + if (!snap->valid || !snap->active) continue; /* Nothing to do if writing beyond end of snapshot */ @@ -1057,6 +1061,9 @@ static int origin_map(struct dm_target *ti, struct bio *bio, struct dm_dev *dev = (struct dm_dev *) ti->private; bio->bi_bdev = dev->bdev; + if (unlikely(bio_barrier(bio))) + return -EOPNOTSUPP; + /* Only tell snapshots if this is a write */ return (bio_rw(bio) == WRITE) ? do_origin(dev, bio) : 1; } @@ -1104,7 +1111,7 @@ static int origin_status(struct dm_target *ti, status_type_t type, char *result, static struct target_type origin_target = { .name = "snapshot-origin", - .version = {1, 0, 1}, + .version = {1, 1, 0}, .module = THIS_MODULE, .ctr = origin_ctr, .dtr = origin_dtr, @@ -1115,7 +1122,7 @@ static struct target_type origin_target = { static struct target_type snapshot_target = { .name = "snapshot", - .version = {1, 0, 1}, + .version = {1, 1, 0}, .module = THIS_MODULE, .ctr = snapshot_ctr, .dtr = snapshot_dtr, |