Merge tag 'fuse-update-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/mszered...

[linux-2.6-microblaze.git] / drivers / md / raid1.c

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 8550542..e2d8acb 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -929,8 +929,10 @@ static void lower_barrier(struct r1conf *conf, sector_t sector_nr)
        wake_up(&conf->wait_barrier);
 }
 
-static void _wait_barrier(struct r1conf *conf, int idx)
+static bool _wait_barrier(struct r1conf *conf, int idx, bool nowait)
 {
+       bool ret = true;
+
        /*
         * We need to increase conf->nr_pending[idx] very early here,
         * then raise_barrier() can be blocked when it waits for
@@ -961,7 +963,7 @@ static void _wait_barrier(struct r1conf *conf, int idx)
         */
        if (!READ_ONCE(conf->array_frozen) &&
            !atomic_read(&conf->barrier[idx]))
-               return;
+               return ret;
 
        /*
         * After holding conf->resync_lock, conf->nr_pending[idx]
@@ -979,18 +981,27 @@ static void _wait_barrier(struct r1conf *conf, int idx)
         */
        wake_up(&conf->wait_barrier);
        /* Wait for the barrier in same barrier unit bucket to drop. */
-       wait_event_lock_irq(conf->wait_barrier,
-                           !conf->array_frozen &&
-                            !atomic_read(&conf->barrier[idx]),
-                           conf->resync_lock);
-       atomic_inc(&conf->nr_pending[idx]);
+
+       /* Return false when nowait flag is set */
+       if (nowait) {
+               ret = false;
+       } else {
+               wait_event_lock_irq(conf->wait_barrier,
+                               !conf->array_frozen &&
+                               !atomic_read(&conf->barrier[idx]),
+                               conf->resync_lock);
+               atomic_inc(&conf->nr_pending[idx]);
+       }
+
        atomic_dec(&conf->nr_waiting[idx]);
        spin_unlock_irq(&conf->resync_lock);
+       return ret;
 }
 
-static void wait_read_barrier(struct r1conf *conf, sector_t sector_nr)
+static bool wait_read_barrier(struct r1conf *conf, sector_t sector_nr, bool nowait)
 {
        int idx = sector_to_idx(sector_nr);
+       bool ret = true;
 
        /*
         * Very similar to _wait_barrier(). The difference is, for read
@@ -1002,7 +1013,7 @@ static void wait_read_barrier(struct r1conf *conf, sector_t sector_nr)
        atomic_inc(&conf->nr_pending[idx]);
 
        if (!READ_ONCE(conf->array_frozen))
-               return;
+               return ret;
 
        spin_lock_irq(&conf->resync_lock);
        atomic_inc(&conf->nr_waiting[idx]);
@@ -1013,19 +1024,28 @@ static void wait_read_barrier(struct r1conf *conf, sector_t sector_nr)
         */
        wake_up(&conf->wait_barrier);
        /* Wait for array to be unfrozen */
-       wait_event_lock_irq(conf->wait_barrier,
-                           !conf->array_frozen,
-                           conf->resync_lock);
-       atomic_inc(&conf->nr_pending[idx]);
+
+       /* Return false when nowait flag is set */
+       if (nowait) {
+               /* Return false when nowait flag is set */
+               ret = false;
+       } else {
+               wait_event_lock_irq(conf->wait_barrier,
+                               !conf->array_frozen,
+                               conf->resync_lock);
+               atomic_inc(&conf->nr_pending[idx]);
+       }
+
        atomic_dec(&conf->nr_waiting[idx]);
        spin_unlock_irq(&conf->resync_lock);
+       return ret;
 }
 
-static void wait_barrier(struct r1conf *conf, sector_t sector_nr)
+static bool wait_barrier(struct r1conf *conf, sector_t sector_nr, bool nowait)
 {
        int idx = sector_to_idx(sector_nr);
 
-       _wait_barrier(conf, idx);
+       return _wait_barrier(conf, idx, nowait);
 }
 
 static void _allow_barrier(struct r1conf *conf, int idx)
@@ -1236,7 +1256,11 @@ static void raid1_read_request(struct mddev *mddev, struct bio *bio,
         * Still need barrier for READ in case that whole
         * array is frozen.
         */
-       wait_read_barrier(conf, bio->bi_iter.bi_sector);
+       if (!wait_read_barrier(conf, bio->bi_iter.bi_sector,
+                               bio->bi_opf & REQ_NOWAIT)) {
+               bio_wouldblock_error(bio);
+               return;
+       }
 
        if (!r1_bio)
                r1_bio = alloc_r1bio(mddev, bio);
@@ -1336,6 +1360,10 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
                     bio->bi_iter.bi_sector, bio_end_sector(bio))) {
 
                DEFINE_WAIT(w);
+               if (bio->bi_opf & REQ_NOWAIT) {
+                       bio_wouldblock_error(bio);
+                       return;
+               }
                for (;;) {
                        prepare_to_wait(&conf->wait_barrier,
                                        &w, TASK_IDLE);
@@ -1353,17 +1381,15 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
         * thread has put up a bar for new requests.
         * Continue immediately if no resync is active currently.
         */
-       wait_barrier(conf, bio->bi_iter.bi_sector);
+       if (!wait_barrier(conf, bio->bi_iter.bi_sector,
+                               bio->bi_opf & REQ_NOWAIT)) {
+               bio_wouldblock_error(bio);
+               return;
+       }
 
        r1_bio = alloc_r1bio(mddev, bio);
        r1_bio->sectors = max_write_sectors;
 
-       if (conf->pending_count >= max_queued_requests) {
-               md_wakeup_thread(mddev->thread);
-               raid1_log(mddev, "wait queued");
-               wait_event(conf->wait_barrier,
-                          conf->pending_count < max_queued_requests);
-       }
        /* first select target devices under rcu_lock and
         * inc refcount on their rdev.  Record them by setting
         * bios[x] to bio
@@ -1458,9 +1484,14 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
                                rdev_dec_pending(conf->mirrors[j].rdev, mddev);
                r1_bio->state = 0;
                allow_barrier(conf, bio->bi_iter.bi_sector);
+
+               if (bio->bi_opf & REQ_NOWAIT) {
+                       bio_wouldblock_error(bio);
+                       return;
+               }
                raid1_log(mddev, "wait rdev %d blocked", blocked_rdev->raid_disk);
                md_wait_for_blocked_rdev(blocked_rdev, mddev);
-               wait_barrier(conf, bio->bi_iter.bi_sector);
+               wait_barrier(conf, bio->bi_iter.bi_sector, false);
                goto retry_write;
        }
 
@@ -1688,7 +1719,7 @@ static void close_sync(struct r1conf *conf)
        int idx;
 
        for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++) {
-               _wait_barrier(conf, idx);
+               _wait_barrier(conf, idx, false);
                _allow_barrier(conf, idx);
        }
 
@@ -3410,5 +3441,3 @@ MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
 MODULE_ALIAS("md-personality-3"); /* RAID1 */
 MODULE_ALIAS("md-raid1");
 MODULE_ALIAS("md-level-1");
-
-module_param(max_queued_requests, int, S_IRUGO|S_IWUSR);