diff options
| author | Mikulas Patocka <mpatocka@redhat.com> | 2009-12-10 23:52:06 +0000 |
|---|---|---|
| committer | Alasdair G Kergon <agk@redhat.com> | 2009-12-10 23:52:06 +0000 |
| commit | 929be8fcb4b4b65d038e73d3bb34715851a95ca2 (patch) | |
| tree | 7c008317d90232b5b2d3869b9fa68c1ec023d7f6 /drivers/md | |
| parent | 60f355ead31e2be8d06ac8acb163df91a1c64e3b (diff) | |
dm raid1: hold all write bios when leg fails
Hold all write bios when leg fails and errors are handled
When using a userspace daemon such as dmeventd to handle errors, we must
delay completing bios until it has done its job.
This patch prevents the following race:
- primary leg fails
- write "1" fail, the write is held, secondary leg is set default
- write "2" goes straight to the secondary leg
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Takahiro Yasui <tyasui@redhat.com>
Tested-by: Takahiro Yasui <tyasui@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-raid1.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c index e363335e8d8..f8d7b3aa46c 100644 --- a/drivers/md/dm-raid1.c +++ b/drivers/md/dm-raid1.c @@ -69,6 +69,7 @@ struct mirror_set { region_t nr_regions; int in_sync; int log_failure; + int leg_failure; atomic_t suspend; atomic_t default_mirror; /* Default mirror */ @@ -211,6 +212,8 @@ static void fail_mirror(struct mirror *m, enum dm_raid1_error error_type) struct mirror_set *ms = m->ms; struct mirror *new; + ms->leg_failure = 1; + /* * error_count is used for nothing more than a * simple way to tell if a device has encountered @@ -734,8 +737,12 @@ static void do_writes(struct mirror_set *ms, struct bio_list *writes) dm_rh_delay(ms->rh, bio); while ((bio = bio_list_pop(&nosync))) { - map_bio(get_default_mirror(ms), bio); - generic_make_request(bio); + if (unlikely(ms->leg_failure) && errors_handled(ms)) + hold_bio(ms, bio); + else { + map_bio(get_default_mirror(ms), bio); + generic_make_request(bio); + } } } @@ -848,6 +855,7 @@ static struct mirror_set *alloc_context(unsigned int nr_mirrors, ms->nr_regions = dm_sector_div_up(ti->len, region_size); ms->in_sync = 0; ms->log_failure = 0; + ms->leg_failure = 0; atomic_set(&ms->suspend, 0); atomic_set(&ms->default_mirror, DEFAULT_MIRROR); |