From: Mikulas Patocka Date: Thu, 10 Dec 2009 23:52:33 +0000 (+0000) Subject: dm snapshot: delay merging a chunk until writes to it complete X-Git-Tag: v2.6.33-rc1~75^2~4 X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=17aa03326d40614db94bc51fbbc92df628a5c97c dm snapshot: delay merging a chunk until writes to it complete Track writes to chunks that are currently being merged and delay merging a chunk until all writes to that chunk finish. Signed-off-by: Mikulas Patocka Reviewed-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 91a47c5..bc52776 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -892,7 +892,7 @@ static void snapshot_merge_next_chunks(struct dm_snapshot *s) s->num_merging_chunks = 1; up_write(&s->lock); - /* !!! FIXME: wait until writes to this chunk drain */ + __check_for_conflicting_io(s, old_chunk); dm_kcopyd_copy(s->kcopyd_client, &src, 1, &dest, 0, merge_callback, s); return; @@ -1635,7 +1635,11 @@ static int snapshot_merge_map(struct dm_target *ti, struct bio *bio, r = DM_MAPIO_SUBMITTED; goto out_unlock; } + remap_exception(s, e, bio, chunk); + + if (bio_rw(bio) == WRITE) + map_context->ptr = track_chunk(s, chunk); goto out_unlock; }