locking/barriers: Convert users of lockless_dereference() to READ_ONCE()

[linux-block.git] / drivers / md / dm-mpath.c

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 11f273d2f018e722b1e9480c5a5eb0e59b0f0048..3f88c9d32f7ecc9a66613d6eb0a3df26cf1dc788 100644 (file)
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -366,7 +366,7 @@ static struct pgpath *choose_path_in_pg(struct multipath *m,
 
        pgpath = path_to_pgpath(path);
 
-       if (unlikely(lockless_dereference(m->current_pg) != pg)) {
+       if (unlikely(READ_ONCE(m->current_pg) != pg)) {
                /* Only update current_pgpath if pg changed */
                spin_lock_irqsave(&m->lock, flags);
                m->current_pgpath = pgpath;
@@ -390,7 +390,7 @@ static struct pgpath *choose_pgpath(struct multipath *m, size_t nr_bytes)
        }
 
        /* Were we instructed to switch PG? */
-       if (lockless_dereference(m->next_pg)) {
+       if (READ_ONCE(m->next_pg)) {
                spin_lock_irqsave(&m->lock, flags);
                pg = m->next_pg;
                if (!pg) {
@@ -406,7 +406,7 @@ static struct pgpath *choose_pgpath(struct multipath *m, size_t nr_bytes)
 
        /* Don't change PG until it has no remaining paths */
 check_current_pg:
-       pg = lockless_dereference(m->current_pg);
+       pg = READ_ONCE(m->current_pg);
        if (pg) {
                pgpath = choose_path_in_pg(m, pg, nr_bytes);
                if (!IS_ERR_OR_NULL(pgpath))
@@ -473,7 +473,7 @@ static int multipath_clone_and_map(struct dm_target *ti, struct request *rq,
        struct request *clone;
 
        /* Do we need to select a new pgpath? */
-       pgpath = lockless_dereference(m->current_pgpath);
+       pgpath = READ_ONCE(m->current_pgpath);
        if (!pgpath || !test_bit(MPATHF_QUEUE_IO, &m->flags))
                pgpath = choose_pgpath(m, nr_bytes);
 
@@ -535,7 +535,7 @@ static int __multipath_map_bio(struct multipath *m, struct bio *bio, struct dm_m
        bool queue_io;
 
        /* Do we need to select a new pgpath? */
-       pgpath = lockless_dereference(m->current_pgpath);
+       pgpath = READ_ONCE(m->current_pgpath);
        queue_io = test_bit(MPATHF_QUEUE_IO, &m->flags);
        if (!pgpath || !queue_io)
                pgpath = choose_pgpath(m, nr_bytes);
@@ -1804,7 +1804,7 @@ static int multipath_prepare_ioctl(struct dm_target *ti,
        struct pgpath *current_pgpath;
        int r;
 
-       current_pgpath = lockless_dereference(m->current_pgpath);
+       current_pgpath = READ_ONCE(m->current_pgpath);
        if (!current_pgpath)
                current_pgpath = choose_pgpath(m, 0);
 
@@ -1826,7 +1826,7 @@ static int multipath_prepare_ioctl(struct dm_target *ti,
        }
 
        if (r == -ENOTCONN) {
-               if (!lockless_dereference(m->current_pg)) {
+               if (!READ_ONCE(m->current_pg)) {
                        /* Path status changed, redo selection */
                        (void) choose_pgpath(m, 0);
                }
@@ -1895,9 +1895,9 @@ static int multipath_busy(struct dm_target *ti)
                return (m->queue_mode != DM_TYPE_MQ_REQUEST_BASED);
 
        /* Guess which priority_group will be used at next mapping time */
-       pg = lockless_dereference(m->current_pg);
-       next_pg = lockless_dereference(m->next_pg);
-       if (unlikely(!lockless_dereference(m->current_pgpath) && next_pg))
+       pg = READ_ONCE(m->current_pg);
+       next_pg = READ_ONCE(m->next_pg);
+       if (unlikely(!READ_ONCE(m->current_pgpath) && next_pg))
                pg = next_pg;
 
        if (!pg) {