From 86331f39a5935b092d3ea59446d416563ed05d16 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 27 Apr 2017 10:11:26 -0700 Subject: dm mpath: make it easier to detect unintended I/O request flushes I/O errors triggered by multipathd incorrectly not enabling the no-flush flag for DM_DEVICE_SUSPEND or DM_DEVICE_RESUME are hard to debug. Add more logging to make it easier to debug this. Signed-off-by: Bart Van Assche Reviewed-by: Hannes Reinecke Signed-off-by: Mike Snitzer --- drivers/md/dm-mpath.c | 25 +++++++++++++++++++++---- 1 file changed, 21 insertions(+), 4 deletions(-) (limited to 'drivers/md/dm-mpath.c') diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index cc529537c8ce..fd7cdc4ce2a5 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -441,6 +441,23 @@ failed: return NULL; } +/* + * dm_report_EIO() is a macro instead of a function to make pr_debug() + * report the function name and line number of the function from which + * it has been invoked. + */ +#define dm_report_EIO(m) \ +({ \ + struct mapped_device *md = dm_table_get_md((m)->ti->table); \ + \ + pr_debug("%s: returning EIO; QIFNP = %d; SQIFNP = %d; DNFS = %d\n", \ + dm_device_name(md), \ + test_bit(MPATHF_QUEUE_IF_NO_PATH, &(m)->flags), \ + test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &(m)->flags), \ + dm_noflush_suspending((m)->ti)); \ + -EIO; \ +}) + /* * Map cloned requests (request-based multipath) */ @@ -464,7 +481,7 @@ static int multipath_clone_and_map(struct dm_target *ti, struct request *rq, if (!pgpath) { if (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) return DM_MAPIO_DELAY_REQUEUE; - return -EIO; /* Failed */ + return dm_report_EIO(m); /* Failed */ } else if (test_bit(MPATHF_QUEUE_IO, &m->flags) || test_bit(MPATHF_PG_INIT_REQUIRED, &m->flags)) { if (pg_init_all_paths(m)) @@ -541,7 +558,7 @@ static int __multipath_map_bio(struct multipath *m, struct bio *bio, struct dm_m if (!pgpath) { if (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) return DM_MAPIO_REQUEUE; - return -EIO; + return dm_report_EIO(m); } mpio->pgpath = pgpath; @@ -1476,7 +1493,7 @@ static int do_end_io(struct multipath *m, struct request *clone, if (atomic_read(&m->nr_valid_paths) == 0 && !test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) - r = -EIO; + r = dm_report_EIO(m); return r; } @@ -1519,7 +1536,7 @@ static int do_end_io_bio(struct multipath *m, struct bio *clone, if (atomic_read(&m->nr_valid_paths) == 0 && !test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) - return -EIO; + return dm_report_EIO(m); /* Queue for the daemon to resubmit */ dm_bio_restore(get_bio_details_from_bio(clone), clone); -- cgit v1.2.3