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authorAlasdair G Kergon <agk@redhat.com>2006-03-27 11:17:50 +0200
committerLinus Torvalds <torvalds@g5.osdl.org>2006-03-27 18:44:59 +0200
commit138728dc96529f20dfe970c470e51885a60e329f (patch)
treea0369a9de402cd8b9a123129c5e8ba7c69ba1a95 /drivers/md/dm-snap.c
parent[PATCH] dm: make sure QUEUE_FLAG_CLUSTER is set properly (diff)
downloadlinux-138728dc96529f20dfe970c470e51885a60e329f.tar.xz
linux-138728dc96529f20dfe970c470e51885a60e329f.zip
[PATCH] dm snapshot: fix kcopyd destructor
Before removing a snapshot, wait for the completion of any kcopyd jobs using it. Do this by maintaining a count (nr_jobs) of how many outstanding jobs each kcopyd_client has. The snapshot destructor first unregisters the snapshot so that no new kcopyd jobs (created by writes to the origin) will reference that particular snapshot. kcopyd_client_destroy() is now run next to wait for the completion of any outstanding jobs before the snapshot exception structures (that those jobs reference) are freed. Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/md/dm-snap.c')
-rw-r--r--drivers/md/dm-snap.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index a5765f9fbe02..08312b46463a 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -559,8 +559,12 @@ static void snapshot_dtr(struct dm_target *ti)
{
struct dm_snapshot *s = (struct dm_snapshot *) ti->private;
+ /* Prevent further origin writes from using this snapshot. */
+ /* After this returns there can be no new kcopyd jobs. */
unregister_snapshot(s);
+ kcopyd_client_destroy(s->kcopyd_client);
+
exit_exception_table(&s->pending, pending_cache);
exit_exception_table(&s->complete, exception_cache);
@@ -569,7 +573,7 @@ static void snapshot_dtr(struct dm_target *ti)
dm_put_device(ti, s->origin);
dm_put_device(ti, s->cow);
- kcopyd_client_destroy(s->kcopyd_client);
+
kfree(s);
}