diff options
author | Mike Snitzer <snitzer@redhat.com> | 2013-12-05 15:47:24 -0500 |
---|---|---|
committer | Mike Snitzer <snitzer@redhat.com> | 2014-01-07 10:14:29 -0500 |
commit | 8c0f0e8c9f07e6554b2281f86f00e769cf805fd9 (patch) | |
tree | 06e1aac7a4705eb7cb5c494c50cd8852a5415f60 | |
parent | 399caddfb16f5fa30c66056a32477cf95c947e2b (diff) |
dm thin: requeue bios to DM core if no_free_space and in read-only mode
Now that we switch the pool to read-only mode when the data device runs
out of space it causes active writers to get IO errors once we resume
after resizing the data device.
If no_free_space is set, save bios to the 'retry_on_resume_list' and
requeue them on resume (once the data or metadata device may have been
resized).
With this patch the resize_io test passes again (on slower storage):
dmtest run --suite thin-provisioning -n /resize_io/
Later patches fix some subtle races associated with the pool mode
transitions done as part of the pool's -ENOSPC handling. These races
are exposed on fast storage (e.g. PCIe SSD).
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
-rw-r--r-- | drivers/md/dm-thin.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 96ce36a1a764..53252d2af249 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -164,7 +164,7 @@ struct pool { struct pool_features pf; bool low_water_triggered:1; /* A dm event has been sent */ - bool no_free_space:1; /* A -ENOSPC warning has been issued */ + bool no_free_space:1; /* bios will be requeued if set */ struct dm_bio_prison *prison; struct dm_kcopyd_client *copier; @@ -982,6 +982,20 @@ static void retry_on_resume(struct bio *bio) spin_unlock_irqrestore(&pool->lock, flags); } +static void handle_unserviceable_bio(struct pool *pool, struct bio *bio) +{ + /* + * When pool is read-only, no cell locking is needed because + * nothing is changing. + */ + WARN_ON_ONCE(get_pool_mode(pool) != PM_READ_ONLY); + + if (pool->no_free_space) + retry_on_resume(bio); + else + bio_io_error(bio); +} + static void retry_bios_on_resume(struct pool *pool, struct dm_bio_prison_cell *cell) { struct bio *bio; @@ -991,7 +1005,7 @@ static void retry_bios_on_resume(struct pool *pool, struct dm_bio_prison_cell *c cell_release(pool, cell, &bios); while ((bio = bio_list_pop(&bios))) - retry_on_resume(bio); + handle_unserviceable_bio(pool, bio); } static void process_discard(struct thin_c *tc, struct bio *bio) @@ -1245,7 +1259,7 @@ static void process_bio_read_only(struct thin_c *tc, struct bio *bio) switch (r) { case 0: if (lookup_result.shared && (rw == WRITE) && bio->bi_size) - bio_io_error(bio); + handle_unserviceable_bio(tc->pool, bio); else { inc_all_io_entry(tc->pool, bio); remap_and_issue(tc, bio, lookup_result.block); @@ -1254,7 +1268,7 @@ static void process_bio_read_only(struct thin_c *tc, struct bio *bio) case -ENODATA: if (rw != READ) { - bio_io_error(bio); + handle_unserviceable_bio(tc->pool, bio); break; } @@ -1565,9 +1579,9 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio) if (get_pool_mode(tc->pool) == PM_READ_ONLY) { /* * This block isn't provisioned, and we have no way - * of doing so. Just error it. + * of doing so. */ - bio_io_error(bio); + handle_unserviceable_bio(tc->pool, bio); return DM_MAPIO_SUBMITTED; } /* fall through */ |