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authorMaarten Lankhorst <maarten.lankhorst@linux.intel.com>2020-06-29 12:15:51 +0200
committerMaarten Lankhorst <maarten.lankhorst@linux.intel.com>2020-06-29 12:16:26 +0200
commit60e9eabf41fa916d2ef68c5bf929197975917578 (patch)
tree39ce456390ed34d2624aed1260203f43fff94d38 /drivers/md/dm-mpath.c
parent84e543bc9d1dc550132ba25b72df28d40cc44333 (diff)
parent0a19b068acc47d05212f03e494381926dc0381e2 (diff)
Backmerge remote-tracking branch 'drm/drm-next' into drm-misc-next
Some conflicts with ttm_bo->offset removal, but drm-misc-next needs updating to v5.8. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Diffstat (limited to 'drivers/md/dm-mpath.c')
-rw-r--r--drivers/md/dm-mpath.c129
1 files changed, 77 insertions, 52 deletions
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 58fd137b6ae1..78cff42d987e 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -439,7 +439,7 @@ failed:
}
/*
- * dm_report_EIO() is a macro instead of a function to make pr_debug()
+ * dm_report_EIO() is a macro instead of a function to make pr_debug_ratelimited()
* report the function name and line number of the function from which
* it has been invoked.
*/
@@ -447,43 +447,25 @@ failed:
do { \
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)); \
+ DMDEBUG_LIMIT("%s: returning EIO; QIFNP = %d; SQIFNP = %d; DNFS = %d", \
+ 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)); \
} while (0)
/*
* Check whether bios must be queued in the device-mapper core rather
* than here in the target.
- *
- * If MPATHF_QUEUE_IF_NO_PATH and MPATHF_SAVED_QUEUE_IF_NO_PATH hold
- * the same value then we are not between multipath_presuspend()
- * and multipath_resume() calls and we have no need to check
- * for the DMF_NOFLUSH_SUSPENDING flag.
*/
-static bool __must_push_back(struct multipath *m, unsigned long flags)
+static bool __must_push_back(struct multipath *m)
{
- return ((test_bit(MPATHF_QUEUE_IF_NO_PATH, &flags) !=
- test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &flags)) &&
- dm_noflush_suspending(m->ti));
+ return dm_noflush_suspending(m->ti);
}
-/*
- * Following functions use READ_ONCE to get atomic access to
- * all m->flags to avoid taking spinlock
- */
static bool must_push_back_rq(struct multipath *m)
{
- unsigned long flags = READ_ONCE(m->flags);
- return test_bit(MPATHF_QUEUE_IF_NO_PATH, &flags) || __must_push_back(m, flags);
-}
-
-static bool must_push_back_bio(struct multipath *m)
-{
- unsigned long flags = READ_ONCE(m->flags);
- return __must_push_back(m, flags);
+ return test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags) || __must_push_back(m);
}
/*
@@ -567,7 +549,8 @@ static void multipath_release_clone(struct request *clone,
if (pgpath && pgpath->pg->ps.type->end_io)
pgpath->pg->ps.type->end_io(&pgpath->pg->ps,
&pgpath->path,
- mpio->nr_bytes);
+ mpio->nr_bytes,
+ clone->io_start_time_ns);
}
blk_put_request(clone);
@@ -585,10 +568,12 @@ static struct pgpath *__map_bio(struct multipath *m, struct bio *bio)
/* Do we need to select a new pgpath? */
pgpath = READ_ONCE(m->current_pgpath);
- queue_io = test_bit(MPATHF_QUEUE_IO, &m->flags);
- if (!pgpath || !queue_io)
+ if (!pgpath || !test_bit(MPATHF_QUEUE_IO, &m->flags))
pgpath = choose_pgpath(m, bio->bi_iter.bi_size);
+ /* MPATHF_QUEUE_IO might have been cleared by choose_pgpath. */
+ queue_io = test_bit(MPATHF_QUEUE_IO, &m->flags);
+
if ((pgpath && queue_io) ||
(!pgpath && test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags))) {
/* Queue for the daemon to resubmit */
@@ -617,7 +602,7 @@ static int __multipath_map_bio(struct multipath *m, struct bio *bio,
return DM_MAPIO_SUBMITTED;
if (!pgpath) {
- if (must_push_back_bio(m))
+ if (__must_push_back(m))
return DM_MAPIO_REQUEUE;
dm_report_EIO(m);
return DM_MAPIO_KILL;
@@ -707,15 +692,38 @@ static void process_queued_bios(struct work_struct *work)
* If we run out of usable paths, should we queue I/O or error it?
*/
static int queue_if_no_path(struct multipath *m, bool queue_if_no_path,
- bool save_old_value)
+ bool save_old_value, const char *caller)
{
unsigned long flags;
+ bool queue_if_no_path_bit, saved_queue_if_no_path_bit;
+ const char *dm_dev_name = dm_device_name(dm_table_get_md(m->ti->table));
+
+ DMDEBUG("%s: %s caller=%s queue_if_no_path=%d save_old_value=%d",
+ dm_dev_name, __func__, caller, queue_if_no_path, save_old_value);
spin_lock_irqsave(&m->lock, flags);
- assign_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags,
- (save_old_value && test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) ||
- (!save_old_value && queue_if_no_path));
+
+ queue_if_no_path_bit = test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags);
+ saved_queue_if_no_path_bit = test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags);
+
+ if (save_old_value) {
+ if (unlikely(!queue_if_no_path_bit && saved_queue_if_no_path_bit)) {
+ DMERR("%s: QIFNP disabled but saved as enabled, saving again loses state, not saving!",
+ dm_dev_name);
+ } else
+ assign_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags, queue_if_no_path_bit);
+ } else if (!queue_if_no_path && saved_queue_if_no_path_bit) {
+ /* due to "fail_if_no_path" message, need to honor it. */
+ clear_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags);
+ }
assign_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags, queue_if_no_path);
+
+ DMDEBUG("%s: after %s changes; QIFNP = %d; SQIFNP = %d; DNFS = %d",
+ dm_dev_name, __func__,
+ test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags),
+ test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags),
+ dm_noflush_suspending(m->ti));
+
spin_unlock_irqrestore(&m->lock, flags);
if (!queue_if_no_path) {
@@ -736,7 +744,7 @@ static void queue_if_no_path_timeout_work(struct timer_list *t)
struct mapped_device *md = dm_table_get_md(m->ti->table);
DMWARN("queue_if_no_path timeout on %s, failing queued IO", dm_device_name(md));
- queue_if_no_path(m, false, false);
+ queue_if_no_path(m, false, false, __func__);
}
/*
@@ -1076,7 +1084,7 @@ static int parse_features(struct dm_arg_set *as, struct multipath *m)
argc--;
if (!strcasecmp(arg_name, "queue_if_no_path")) {
- r = queue_if_no_path(m, true, false);
+ r = queue_if_no_path(m, true, false, __func__);
continue;
}
@@ -1277,7 +1285,9 @@ static int fail_path(struct pgpath *pgpath)
if (!pgpath->is_active)
goto out;
- DMWARN("Failing path %s.", pgpath->path.dev->name);
+ DMWARN("%s: Failing path %s.",
+ dm_device_name(dm_table_get_md(m->ti->table)),
+ pgpath->path.dev->name);
pgpath->pg->ps.type->fail_path(&pgpath->pg->ps, &pgpath->path);
pgpath->is_active = false;
@@ -1316,7 +1326,9 @@ static int reinstate_path(struct pgpath *pgpath)
if (pgpath->is_active)
goto out;
- DMWARN("Reinstating path %s.", pgpath->path.dev->name);
+ DMWARN("%s: Reinstating path %s.",
+ dm_device_name(dm_table_get_md(m->ti->table)),
+ pgpath->path.dev->name);
r = pgpath->pg->ps.type->reinstate_path(&pgpath->pg->ps, &pgpath->path);
if (r)
@@ -1615,7 +1627,8 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone,
struct path_selector *ps = &pgpath->pg->ps;
if (ps->type->end_io)
- ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
+ ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes,
+ clone->io_start_time_ns);
}
return r;
@@ -1638,7 +1651,7 @@ static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone,
if (atomic_read(&m->nr_valid_paths) == 0 &&
!test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
- if (must_push_back_bio(m)) {
+ if (__must_push_back(m)) {
r = DM_ENDIO_REQUEUE;
} else {
dm_report_EIO(m);
@@ -1659,23 +1672,27 @@ done:
struct path_selector *ps = &pgpath->pg->ps;
if (ps->type->end_io)
- ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
+ ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes,
+ dm_start_time_ns_from_clone(clone));
}
return r;
}
/*
- * Suspend can't complete until all the I/O is processed so if
- * the last path fails we must error any remaining I/O.
- * Note that if the freeze_bdev fails while suspending, the
- * queue_if_no_path state is lost - userspace should reset it.
+ * Suspend with flush can't complete until all the I/O is processed
+ * so if the last path fails we must error any remaining I/O.
+ * - Note that if the freeze_bdev fails while suspending, the
+ * queue_if_no_path state is lost - userspace should reset it.
+ * Otherwise, during noflush suspend, queue_if_no_path will not change.
*/
static void multipath_presuspend(struct dm_target *ti)
{
struct multipath *m = ti->private;
- queue_if_no_path(m, false, true);
+ /* FIXME: bio-based shouldn't need to always disable queue_if_no_path */
+ if (m->queue_mode == DM_TYPE_BIO_BASED || !dm_noflush_suspending(m->ti))
+ queue_if_no_path(m, false, true, __func__);
}
static void multipath_postsuspend(struct dm_target *ti)
@@ -1696,8 +1713,16 @@ static void multipath_resume(struct dm_target *ti)
unsigned long flags;
spin_lock_irqsave(&m->lock, flags);
- assign_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags,
- test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags));
+ if (test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags)) {
+ set_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags);
+ clear_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags);
+ }
+
+ DMDEBUG("%s: %s finished; QIFNP = %d; SQIFNP = %d",
+ dm_device_name(dm_table_get_md(m->ti->table)), __func__,
+ test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags),
+ test_bit(MPATHF_SAVED_QUEUE_IF_NO_PATH, &m->flags));
+
spin_unlock_irqrestore(&m->lock, flags);
}
@@ -1857,13 +1882,13 @@ static int multipath_message(struct dm_target *ti, unsigned argc, char **argv,
if (argc == 1) {
if (!strcasecmp(argv[0], "queue_if_no_path")) {
- r = queue_if_no_path(m, true, false);
+ r = queue_if_no_path(m, true, false, __func__);
spin_lock_irqsave(&m->lock, flags);
enable_nopath_timeout(m);
spin_unlock_irqrestore(&m->lock, flags);
goto out;
} else if (!strcasecmp(argv[0], "fail_if_no_path")) {
- r = queue_if_no_path(m, false, false);
+ r = queue_if_no_path(m, false, false, __func__);
disable_nopath_timeout(m);
goto out;
}
@@ -1916,7 +1941,7 @@ static int multipath_prepare_ioctl(struct dm_target *ti,
int r;
current_pgpath = READ_ONCE(m->current_pgpath);
- if (!current_pgpath)
+ if (!current_pgpath || !test_bit(MPATHF_QUEUE_IO, &m->flags))
current_pgpath = choose_pgpath(m, 0);
if (current_pgpath) {