diff options
| author | Mike Snitzer <snitzer@kernel.org> | 2022-04-14 11:52:54 -0400 |
|---|---|---|
| committer | Mike Snitzer <snitzer@kernel.org> | 2022-04-14 20:01:54 -0400 |
| commit | 7dd06a2548b2bf516ef2e79873a9cdd00b354b99 (patch) | |
| tree | 1383e1cbfb0755d97b8fabca747438d374f5b03a /drivers/md | |
| parent | 73d7b06e902dd294e1f61554f7c403d0f705cf92 (diff) | |
dm: allow dm_accept_partial_bio() for dm_io without duplicate bios
The intent behind commit e6fc9f62ce6e ("dm: flag clones created by
__send_duplicate_bios") was to formally disallow the use of
dm_accept_partial_bio() where it simply isn't possible -- due to
constraint that multiple bios cannot meaningfully update a shared
tio->len_ptr.
But that commit went too far and disallowed the case where "abormal"
IO (e.g. WRITE_ZEROES) is only using a single bio. Fix this by
not marking a dm_io with a single dm_target_io (and bio), that happens
to be created by __send_duplicate_bios, as DM_TIO_IS_DUPLICATE_BIO.
Also remove 'unsigned *len' parameter from alloc_multiple_bios().
This commit fixes a dm_accept_partial_bio() BUG_ON() with dm-zoned
when a WRITE_ZEROES bio is issued.
Fixes: 655f3aad7aa4 ("dm: switch dm_target_io booleans over to proper flags")
Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm.c | 17 |
1 files changed, 6 insertions, 11 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 3c5fad7c4ee6..fc1f9583a271 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1323,8 +1323,7 @@ static void __map_bio(struct bio *clone) } static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, - struct dm_target *ti, unsigned num_bios, - unsigned *len) + struct dm_target *ti, unsigned num_bios) { struct bio *bio; int try; @@ -1335,7 +1334,7 @@ static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, if (try) mutex_lock(&ci->io->md->table_devices_lock); for (bio_nr = 0; bio_nr < num_bios; bio_nr++) { - bio = alloc_tio(ci, ti, bio_nr, len, + bio = alloc_tio(ci, ti, bio_nr, NULL, try ? GFP_NOIO : GFP_NOWAIT); if (!bio) break; @@ -1363,11 +1362,11 @@ static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, break; case 1: clone = alloc_tio(ci, ti, 0, len, GFP_NOIO); - dm_tio_set_flag(clone_to_tio(clone), DM_TIO_IS_DUPLICATE_BIO); __map_bio(clone); break; default: - alloc_multiple_bios(&blist, ci, ti, num_bios, len); + /* dm_accept_partial_bio() is not supported with shared tio->len_ptr */ + alloc_multiple_bios(&blist, ci, ti, num_bios); while ((clone = bio_list_pop(&blist))) { dm_tio_set_flag(clone_to_tio(clone), DM_TIO_IS_DUPLICATE_BIO); __map_bio(clone); @@ -1407,14 +1406,10 @@ static void __send_changing_extent_only(struct clone_info *ci, struct dm_target len = min_t(sector_t, ci->sector_count, max_io_len_target_boundary(ti, dm_target_offset(ti, ci->sector))); - /* - * dm_accept_partial_bio cannot be used with duplicate bios, - * so update clone_info cursor before __send_duplicate_bios(). - */ + __send_duplicate_bios(ci, ti, num_bios, &len); + ci->sector += len; ci->sector_count -= len; - - __send_duplicate_bios(ci, ti, num_bios, &len); } static bool is_abnormal_io(struct bio *bio) |