diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2020-06-10 15:02:37 -0400 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2020-07-13 11:47:32 -0400 |
| commit | 69cea0d45a618ad4ae74f36386ef1af5128b2b19 (patch) | |
| tree | ecc2ec6341ec5e5c5339fba4075eafab467573fb | |
| parent | 11ba468877bb23f28956a35e896356252d63c983 (diff) | |
| download | linux-69cea0d45a618ad4ae74f36386ef1af5128b2b19.tar.bz2 | |
dm mpath: changes from initial m->flags locking audit
Fix locking in slow-paths where m->lock should be taken.
Signed-off-by: Mike Snitzer <snitzer@rredhat.com>
| -rw-r--r-- | drivers/md/dm-mpath.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 78cff42d987e..d7bb74bded8c 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -335,6 +335,8 @@ static int pg_init_all_paths(struct multipath *m) static void __switch_pg(struct multipath *m, struct priority_group *pg) { + lockdep_assert_held(&m->lock); + m->current_pg = pg; /* Must we initialise the PG first, and queue I/O till it's ready? */ @@ -382,7 +384,9 @@ static struct pgpath *choose_pgpath(struct multipath *m, size_t nr_bytes) unsigned bypassed = 1; if (!atomic_read(&m->nr_valid_paths)) { + spin_lock_irqsave(&m->lock, flags); clear_bit(MPATHF_QUEUE_IO, &m->flags); + spin_unlock_irqrestore(&m->lock, flags); goto failed; } @@ -422,8 +426,11 @@ check_current_pg: continue; pgpath = choose_path_in_pg(m, pg, nr_bytes); if (!IS_ERR_OR_NULL(pgpath)) { - if (!bypassed) + if (!bypassed) { + spin_lock_irqsave(&m->lock, flags); set_bit(MPATHF_PG_INIT_DELAY_RETRY, &m->flags); + spin_unlock_irqrestore(&m->lock, flags); + } return pgpath; } } @@ -1662,9 +1669,9 @@ static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, spin_lock_irqsave(&m->lock, flags); bio_list_add(&m->queued_bios, clone); - spin_unlock_irqrestore(&m->lock, flags); if (!test_bit(MPATHF_QUEUE_IO, &m->flags)) queue_work(kmultipathd, &m->process_queued_bios); + spin_unlock_irqrestore(&m->lock, flags); r = DM_ENDIO_INCOMPLETE; done: @@ -1938,6 +1945,7 @@ static int multipath_prepare_ioctl(struct dm_target *ti, { struct multipath *m = ti->private; struct pgpath *current_pgpath; + unsigned long flags; int r; current_pgpath = READ_ONCE(m->current_pgpath); @@ -1965,8 +1973,10 @@ static int multipath_prepare_ioctl(struct dm_target *ti, /* Path status changed, redo selection */ (void) choose_pgpath(m, 0); } + spin_lock_irqsave(&m->lock, flags); if (test_bit(MPATHF_PG_INIT_REQUIRED, &m->flags)) - pg_init_all_paths(m); + (void) __pg_init_all_paths(m); + spin_unlock_irqrestore(&m->lock, flags); dm_table_run_md_queue_async(m->ti->table); process_queued_io_list(m); } |