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 <bart.vanass...@sandisk.com>
Reviewed-by: Hannes Reinecke <h...@suse.com>
---
drivers/md/dm-mpath.c | 25 +++++++++++++++++++++----
drivers/md/dm.c | 3 +++
2 files changed, 24 insertions(+), 4 deletions(-)
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 6cab04a0e565..1971952396cf 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -442,6 +442,23 @@ static struct pgpath *choose_pgpath(struct multipath *m,
size_t nr_bytes)
}
/*
+ * Note: 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)
*/
static int multipath_clone_and_map(struct dm_target *ti, struct request *rq,
@@ -466,7 +483,7 @@ static int multipath_clone_and_map(struct dm_target *ti,
struct request *rq,
pr_debug("no path - requeueing\n");
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)) {
return pg_init_all_paths(m) == 0 ? DM_MAPIO_REQUEUE :
@@ -542,7 +559,7 @@ 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;
@@ -1484,7 +1501,7 @@ 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;
}
@@ -1527,7 +1544,7 @@ 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);
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 7161c7804363..9f0aed0e1bf0 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2158,6 +2158,9 @@ static int __dm_suspend(struct mapped_device *md, struct
dm_table *map,
*/
if (noflush)
set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
+ else
+ pr_debug("%s: suspending without no-flush flag\n",
+ dm_device_name(md));
/*
* This gets reverted if there's an error later and the targets
--
2.12.2
--
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