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path: root/drivers/md/raid1.c
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Diffstat (limited to 'drivers/md/raid1.c')
-rw-r--r--drivers/md/raid1.c83
1 files changed, 56 insertions, 27 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 7dc8026cf6ee..02db187090fa 100644
--- 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;
}
@@ -1687,7 +1718,7 @@ 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);
}
@@ -3409,5 +3440,3 @@ 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);