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-rw-r--r--drivers/md/dm-raid.c11
-rw-r--r--drivers/md/md.c20
-rw-r--r--drivers/md/md.h2
-rw-r--r--drivers/md/raid0.c14
-rw-r--r--drivers/md/raid10.c423
-rw-r--r--drivers/md/raid10.h1
6 files changed, 80 insertions, 391 deletions
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 9c1f7c4de65b..dc8568ab96f2 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3728,6 +3728,17 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
blk_limits_io_min(limits, chunk_size_bytes);
blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));
+
+ /*
+ * RAID10 personality requires bio splitting,
+ * RAID0/1/4/5/6 don't and process large discard bios properly.
+ */
+ if (rs_is_raid10(rs)) {
+ limits->discard_granularity = max(chunk_size_bytes,
+ limits->discard_granularity);
+ limits->max_discard_sectors = min_not_zero(rs->md.chunk_sectors,
+ limits->max_discard_sectors);
+ }
}
static void raid_postsuspend(struct dm_target *ti)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 98bac4f304ae..0037c6ecab65 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8582,26 +8582,6 @@ void md_write_end(struct mddev *mddev)
EXPORT_SYMBOL(md_write_end);
-/* This is used by raid0 and raid10 */
-void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
- struct bio *bio, sector_t start, sector_t size)
-{
- struct bio *discard_bio = NULL;
-
- if (__blkdev_issue_discard(rdev->bdev, start, size,
- GFP_NOIO, 0, &discard_bio) || !discard_bio)
- return;
-
- bio_chain(discard_bio, bio);
- bio_clone_blkg_association(discard_bio, bio);
- if (mddev->gendisk)
- trace_block_bio_remap(bdev_get_queue(rdev->bdev),
- discard_bio, disk_devt(mddev->gendisk),
- bio->bi_iter.bi_sector);
- submit_bio_noacct(discard_bio);
-}
-EXPORT_SYMBOL(md_submit_discard_bio);
-
/* md_allow_write(mddev)
* Calling this ensures that the array is marked 'active' so that writes
* may proceed without blocking. It is important to call this before
diff --git a/drivers/md/md.h b/drivers/md/md.h
index ccfb69868c2e..2175a5ac4f7c 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -713,8 +713,6 @@ extern void md_write_end(struct mddev *mddev);
extern void md_done_sync(struct mddev *mddev, int blocks, int ok);
extern void md_error(struct mddev *mddev, struct md_rdev *rdev);
extern void md_finish_reshape(struct mddev *mddev);
-extern void md_submit_discard_bio(struct mddev *mddev, struct md_rdev *rdev,
- struct bio *bio, sector_t start, sector_t size);
extern bool __must_check md_flush_request(struct mddev *mddev, struct bio *bio);
extern void md_super_write(struct mddev *mddev, struct md_rdev *rdev,
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index 6f44177593a5..35843df15b5e 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -477,6 +477,7 @@ static void raid0_handle_discard(struct mddev *mddev, struct bio *bio)
for (disk = 0; disk < zone->nb_dev; disk++) {
sector_t dev_start, dev_end;
+ struct bio *discard_bio = NULL;
struct md_rdev *rdev;
if (disk < start_disk_index)
@@ -499,9 +500,18 @@ static void raid0_handle_discard(struct mddev *mddev, struct bio *bio)
rdev = conf->devlist[(zone - conf->strip_zone) *
conf->strip_zone[0].nb_dev + disk];
- md_submit_discard_bio(mddev, rdev, bio,
+ if (__blkdev_issue_discard(rdev->bdev,
dev_start + zone->dev_start + rdev->data_offset,
- dev_end - dev_start);
+ dev_end - dev_start, GFP_NOIO, 0, &discard_bio) ||
+ !discard_bio)
+ continue;
+ bio_chain(discard_bio, bio);
+ bio_clone_blkg_association(discard_bio, bio);
+ if (mddev->gendisk)
+ trace_block_bio_remap(bdev_get_queue(rdev->bdev),
+ discard_bio, disk_devt(mddev->gendisk),
+ bio->bi_iter.bi_sector);
+ submit_bio_noacct(discard_bio);
}
bio_endio(bio);
}
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index b7bca6703df8..3b598a3cb462 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -91,7 +91,7 @@ static inline struct r10bio *get_resync_r10bio(struct bio *bio)
static void * r10bio_pool_alloc(gfp_t gfp_flags, void *data)
{
struct r10conf *conf = data;
- int size = offsetof(struct r10bio, devs[conf->geo.raid_disks]);
+ int size = offsetof(struct r10bio, devs[conf->copies]);
/* allocate a r10bio with room for raid_disks entries in the
* bios array */
@@ -238,7 +238,7 @@ static void put_all_bios(struct r10conf *conf, struct r10bio *r10_bio)
{
int i;
- for (i = 0; i < conf->geo.raid_disks; i++) {
+ for (i = 0; i < conf->copies; i++) {
struct bio **bio = & r10_bio->devs[i].bio;
if (!BIO_SPECIAL(*bio))
bio_put(*bio);
@@ -327,7 +327,7 @@ static int find_bio_disk(struct r10conf *conf, struct r10bio *r10_bio,
int slot;
int repl = 0;
- for (slot = 0; slot < conf->geo.raid_disks; slot++) {
+ for (slot = 0; slot < conf->copies; slot++) {
if (r10_bio->devs[slot].bio == bio)
break;
if (r10_bio->devs[slot].repl_bio == bio) {
@@ -336,6 +336,7 @@ static int find_bio_disk(struct r10conf *conf, struct r10bio *r10_bio,
}
}
+ BUG_ON(slot == conf->copies);
update_head_pos(slot, r10_bio);
if (slotp)
@@ -1275,75 +1276,12 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio,
}
}
-static void wait_blocked_dev(struct mddev *mddev, struct r10bio *r10_bio)
-{
- int i;
- struct r10conf *conf = mddev->private;
- struct md_rdev *blocked_rdev;
-
-retry_wait:
- blocked_rdev = NULL;
- rcu_read_lock();
- for (i = 0; i < conf->copies; i++) {
- struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
- struct md_rdev *rrdev = rcu_dereference(
- conf->mirrors[i].replacement);
- if (rdev == rrdev)
- rrdev = NULL;
- if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
- atomic_inc(&rdev->nr_pending);
- blocked_rdev = rdev;
- break;
- }
- if (rrdev && unlikely(test_bit(Blocked, &rrdev->flags))) {
- atomic_inc(&rrdev->nr_pending);
- blocked_rdev = rrdev;
- break;
- }
-
- if (rdev && test_bit(WriteErrorSeen, &rdev->flags)) {
- sector_t first_bad;
- sector_t dev_sector = r10_bio->devs[i].addr;
- int bad_sectors;
- int is_bad;
-
- /* Discard request doesn't care the write result
- * so it doesn't need to wait blocked disk here.
- */
- if (!r10_bio->sectors)
- continue;
-
- is_bad = is_badblock(rdev, dev_sector, r10_bio->sectors,
- &first_bad, &bad_sectors);
- if (is_bad < 0) {
- /* Mustn't write here until the bad block
- * is acknowledged
- */
- atomic_inc(&rdev->nr_pending);
- set_bit(BlockedBadBlocks, &rdev->flags);
- blocked_rdev = rdev;
- break;
- }
- }
- }
- rcu_read_unlock();
-
- if (unlikely(blocked_rdev)) {
- /* Have to wait for this device to get unblocked, then retry */
- allow_barrier(conf);
- raid10_log(conf->mddev, "%s wait rdev %d blocked",
- __func__, blocked_rdev->raid_disk);
- md_wait_for_blocked_rdev(blocked_rdev, mddev);
- wait_barrier(conf);
- goto retry_wait;
- }
-}
-
static void raid10_write_request(struct mddev *mddev, struct bio *bio,
struct r10bio *r10_bio)
{
struct r10conf *conf = mddev->private;
int i;
+ struct md_rdev *blocked_rdev;
sector_t sectors;
int max_sectors;
@@ -1401,9 +1339,8 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
r10_bio->read_slot = -1; /* make sure repl_bio gets freed */
raid10_find_phys(conf, r10_bio);
-
- wait_blocked_dev(mddev, r10_bio);
-
+retry_write:
+ blocked_rdev = NULL;
rcu_read_lock();
max_sectors = r10_bio->sectors;
@@ -1414,6 +1351,16 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
conf->mirrors[d].replacement);
if (rdev == rrdev)
rrdev = NULL;
+ if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
+ atomic_inc(&rdev->nr_pending);
+ blocked_rdev = rdev;
+ break;
+ }
+ if (rrdev && unlikely(test_bit(Blocked, &rrdev->flags))) {
+ atomic_inc(&rrdev->nr_pending);
+ blocked_rdev = rrdev;
+ break;
+ }
if (rdev && (test_bit(Faulty, &rdev->flags)))
rdev = NULL;
if (rrdev && (test_bit(Faulty, &rrdev->flags)))
@@ -1434,6 +1381,15 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
is_bad = is_badblock(rdev, dev_sector, max_sectors,
&first_bad, &bad_sectors);
+ if (is_bad < 0) {
+ /* Mustn't write here until the bad block
+ * is acknowledged
+ */
+ atomic_inc(&rdev->nr_pending);
+ set_bit(BlockedBadBlocks, &rdev->flags);
+ blocked_rdev = rdev;
+ break;
+ }
if (is_bad && first_bad <= dev_sector) {
/* Cannot write here at all */
bad_sectors -= (dev_sector - first_bad);
@@ -1469,6 +1425,35 @@ static void raid10_write_request(struct mddev *mddev, struct bio *bio,
}
rcu_read_unlock();
+ if (unlikely(blocked_rdev)) {
+ /* Have to wait for this device to get unblocked, then retry */
+ int j;
+ int d;
+
+ for (j = 0; j < i; j++) {
+ if (r10_bio->devs[j].bio) {
+ d = r10_bio->devs[j].devnum;
+ rdev_dec_pending(conf->mirrors[d].rdev, mddev);
+ }
+ if (r10_bio->devs[j].repl_bio) {
+ struct md_rdev *rdev;
+ d = r10_bio->devs[j].devnum;
+ rdev = conf->mirrors[d].replacement;
+ if (!rdev) {
+ /* Race with remove_disk */
+ smp_mb();
+ rdev = conf->mirrors[d].rdev;
+ }
+ rdev_dec_pending(rdev, mddev);
+ }
+ }
+ allow_barrier(conf);
+ raid10_log(conf->mddev, "wait rdev %d blocked", blocked_rdev->raid_disk);
+ md_wait_for_blocked_rdev(blocked_rdev, mddev);
+ wait_barrier(conf);
+ goto retry_write;
+ }
+
if (max_sectors < r10_bio->sectors)
r10_bio->sectors = max_sectors;
@@ -1508,7 +1493,7 @@ static void __make_request(struct mddev *mddev, struct bio *bio, int sectors)
r10_bio->mddev = mddev;
r10_bio->sector = bio->bi_iter.bi_sector;
r10_bio->state = 0;
- memset(r10_bio->devs, 0, sizeof(r10_bio->devs[0]) * conf->geo.raid_disks);
+ memset(r10_bio->devs, 0, sizeof(r10_bio->devs[0]) * conf->copies);
if (bio_data_dir(bio) == READ)
raid10_read_request(mddev, bio, r10_bio);
@@ -1516,296 +1501,6 @@ static void __make_request(struct mddev *mddev, struct bio *bio, int sectors)
raid10_write_request(mddev, bio, r10_bio);
}
-static struct bio *raid10_split_bio(struct r10conf *conf,
- struct bio *bio, sector_t sectors, bool want_first)
-{
- struct bio *split;
-
- split = bio_split(bio, sectors, GFP_NOIO, &conf->bio_split);
- bio_chain(split, bio);
- allow_barrier(conf);
- if (want_first) {
- submit_bio_noacct(bio);
- bio = split;
- } else
- submit_bio_noacct(split);
- wait_barrier(conf);
-
- return bio;
-}
-
-static void raid_end_discard_bio(struct r10bio *r10bio)
-{
- struct r10conf *conf = r10bio->mddev->private;
- struct r10bio *first_r10bio;
-
- while (atomic_dec_and_test(&r10bio->remaining)) {
-
- allow_barrier(conf);
-
- if (!test_bit(R10BIO_Discard, &r10bio->state)) {
- first_r10bio = (struct r10bio *)r10bio->master_bio;
- free_r10bio(r10bio);
- r10bio = first_r10bio;
- } else {
- md_write_end(r10bio->mddev);
- bio_endio(r10bio->master_bio);
- free_r10bio(r10bio);
- break;
- }
- }
-}
-
-static void raid10_end_discard_request(struct bio *bio)
-{
- struct r10bio *r10_bio = bio->bi_private;
- struct r10conf *conf = r10_bio->mddev->private;
- struct md_rdev *rdev = NULL;
- int dev;
- int slot, repl;
-
- /*
- * We don't care the return value of discard bio
- */
- if (!test_bit(R10BIO_Uptodate, &r10_bio->state))
- set_bit(R10BIO_Uptodate, &r10_bio->state);
-
- dev = find_bio_disk(conf, r10_bio, bio, &slot, &repl);
- if (repl)
- rdev = conf->mirrors[dev].replacement;
- if (!rdev) {
- /* raid10_remove_disk uses smp_mb to make sure rdev is set to
- * replacement before setting replacement to NULL. It can read
- * rdev first without barrier protect even replacment is NULL
- */
- smp_rmb();
- rdev = conf->mirrors[dev].rdev;
- }
-
- raid_end_discard_bio(r10_bio);
- rdev_dec_pending(rdev, conf->mddev);
-}
-
-/* There are some limitations to handle discard bio
- * 1st, the discard size is bigger than stripe_size*2.
- * 2st, if the discard bio spans reshape progress, we use the old way to
- * handle discard bio
- */
-static int raid10_handle_discard(struct mddev *mddev, struct bio *bio)
-{
- struct r10conf *conf = mddev->private;
- struct geom *geo = &conf->geo;
- struct r10bio *r10_bio, *first_r10bio;
- int far_copies = geo->far_copies;
- bool first_copy = true;
-
- int disk;
- sector_t chunk;
- unsigned int stripe_size;
- sector_t split_size;
-
- sector_t bio_start, bio_end;
- sector_t first_stripe_index, last_stripe_index;
- sector_t start_disk_offset;
- unsigned int start_disk_index;
- sector_t end_disk_offset;
- unsigned int end_disk_index;
- unsigned int remainder;
-
- if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
- return -EAGAIN;
-
- wait_barrier(conf);
-
- /* Check reshape again to avoid reshape happens after checking
- * MD_RECOVERY_RESHAPE and before wait_barrier
- */
- if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
- goto out;
-
- stripe_size = geo->raid_disks << geo->chunk_shift;
- bio_start = bio->bi_iter.bi_sector;
- bio_end = bio_end_sector(bio);
-
- /* Maybe one discard bio is smaller than strip size or across one stripe
- * and discard region is larger than one stripe size. For far offset layout,
- * if the discard region is not aligned with stripe size, there is hole
- * when we submit discard bio to member disk. For simplicity, we only
- * handle discard bio which discard region is bigger than stripe_size*2
- */
- if (bio_sectors(bio) < stripe_size*2)
- goto out;
-
- /* For far and far offset layout, if bio is not aligned with stripe size,
- * it splits the part that is not aligned with strip size.
- */
- div_u64_rem(bio_start, stripe_size, &remainder);
- if ((far_copies > 1) && remainder) {
- split_size = stripe_size - remainder;
- bio = raid10_split_bio(conf, bio, split_size, false);
- }
- div_u64_rem(bio_end, stripe_size, &remainder);
- if ((far_copies > 1) && remainder) {
- split_size = bio_sectors(bio) - remainder;
- bio = raid10_split_bio(conf, bio, split_size, true);
- }
-
- bio_start = bio->bi_iter.bi_sector;
- bio_end = bio_end_sector(bio);
-
- /* raid10 uses chunk as the unit to store data. It's similar like raid0.
- * One stripe contains the chunks from all member disk (one chunk from
- * one disk at the same HBA address). For layout detail, see 'man md 4'
- */
- chunk = bio_start >> geo->chunk_shift;
- chunk *= geo->near_copies;
- first_stripe_index = chunk;
- start_disk_index = sector_div(first_stripe_index, geo->raid_disks);
- if (geo->far_offset)
- first_stripe_index *= geo->far_copies;
- start_disk_offset = (bio_start & geo->chunk_mask) +
- (first_stripe_index << geo->chunk_shift);
-
- chunk = bio_end >> geo->chunk_shift;
- chunk *= geo->near_copies;
- last_stripe_index = chunk;
- end_disk_index = sector_div(last_stripe_index, geo->raid_disks);
- if (geo->far_offset)
- last_stripe_index *= geo->far_copies;
- end_disk_offset = (bio_end & geo->chunk_mask) +
- (last_stripe_index << geo->chunk_shift);
-
-retry_discard:
- r10_bio = mempool_alloc(&conf->r10bio_pool, GFP_NOIO);
- r10_bio->mddev = mddev;
- r10_bio->state = 0;
- r10_bio->sectors = 0;
- memset(r10_bio->devs, 0, sizeof(r10_bio->devs[0]) * geo->raid_disks);
- wait_blocked_dev(mddev, r10_bio);
-
- /* For far layout it needs more than one r10bio to cover all regions.
- * Inspired by raid10_sync_request, we can use the first r10bio->master_bio
- * to record the discard bio. Other r10bio->master_bio record the first
- * r10bio. The first r10bio only release after all other r10bios finish.
- * The discard bio returns only first r10bio finishes
- */
- if (first_copy) {
- r10_bio->master_bio = bio;
- set_bit(R10BIO_Discard, &r10_bio->state);
- first_copy = false;
- first_r10bio = r10_bio;
- } else
- r10_bio->master_bio = (struct bio *)first_r10bio;
-
- rcu_read_lock();
- for (disk = 0; disk < geo->raid_disks; disk++) {
- struct md_rdev *rdev = rcu_dereference(conf->mirrors[disk].rdev);
- struct md_rdev *rrdev = rcu_dereference(
- conf->mirrors[disk].replacement);
-
- r10_bio->devs[disk].bio = NULL;
- r10_bio->devs[disk].repl_bio = NULL;
-
- if (rdev && (test_bit(Faulty, &rdev->flags)))
- rdev = NULL;
- if (rrdev && (test_bit(Faulty, &rrdev->flags)))
- rrdev = NULL;
- if (!rdev && !rrdev)
- continue;
-
- if (rdev) {
- r10_bio->devs[disk].bio = bio;
- atomic_inc(&rdev->nr_pending);
- }
- if (rrdev) {
- r10_bio->devs[disk].repl_bio = bio;
- atomic_inc(&rrdev->nr_pending);
- }
- }
- rcu_read_unlock();
-
- atomic_set(&r10_bio->remaining, 1);
- for (disk = 0; disk < geo->raid_disks; disk++) {
- sector_t dev_start, dev_end;
- struct bio *mbio, *rbio = NULL;
- struct md_rdev *rdev = rcu_dereference(conf->mirrors[disk].rdev);
- struct md_rdev *rrdev = rcu_dereference(
- conf->mirrors[disk].replacement);
-
- /*
- * Now start to calculate the start and end address for each disk.
- * The space between dev_start and dev_end is the discard region.
- *
- * For dev_start, it needs to consider three conditions:
- * 1st, the disk is before start_disk, you can imagine the disk in
- * the next stripe. So the dev_start is the start address of next
- * stripe.
- * 2st, the disk is after start_disk, it means the disk is at the
- * same stripe of first disk
- * 3st, the first disk itself, we can use start_disk_offset directly
- */
- if (disk < start_disk_index)
- dev_start = (first_stripe_index + 1) * mddev->chunk_sectors;
- else if (disk > start_disk_index)
- dev_start = first_stripe_index * mddev->chunk_sectors;
- else
- dev_start = start_disk_offset;
-
- if (disk < end_disk_index)
- dev_end = (last_stripe_index + 1) * mddev->chunk_sectors;
- else if (disk > end_disk_index)
- dev_end = last_stripe_index * mddev->chunk_sectors;
- else
- dev_end = end_disk_offset;
-
- /* It only handles discard bio which size is >= stripe size, so
- * dev_end > dev_start all the time
- */
- if (r10_bio->devs[disk].bio) {
- mbio = bio_clone_fast(bio, GFP_NOIO, &mddev->bio_set);
- mbio->bi_end_io = raid10_end_discard_request;
- mbio->bi_private = r10_bio;
- r10_bio->devs[disk].bio = mbio;
- r10_bio->devs[disk].devnum = disk;
- atomic_inc(&r10_bio->remaining);
- md_submit_discard_bio(mddev, rdev, mbio,
- dev_start + choose_data_offset(r10_bio, rdev),
- dev_end - dev_start);
- bio_endio(mbio);
- }
- if (r10_bio->devs[disk].repl_bio) {
- rbio = bio_clone_fast(bio, GFP_NOIO, &mddev->bio_set);
- rbio->bi_end_io = raid10_end_discard_request;
- rbio->bi_private = r10_bio;
- r10_bio->devs[disk].repl_bio = rbio;
- r10_bio->devs[disk].devnum = disk;
- atomic_inc(&r10_bio->remaining);
- md_submit_discard_bio(mddev, rrdev, rbio,
- dev_start + choose_data_offset(r10_bio, rrdev),
- dev_end - dev_start);
- bio_endio(rbio);
- }
- }
-
- if (!geo->far_offset && --far_copies) {
- first_stripe_index += geo->stride >> geo->chunk_shift;
- start_disk_offset += geo->stride;
- last_stripe_index += geo->stride >> geo->chunk_shift;
- end_disk_offset += geo->stride;
- atomic_inc(&first_r10bio->remaining);
- raid_end_discard_bio(r10_bio);
- wait_barrier(conf);
- goto retry_discard;
- }
-
- raid_end_discard_bio(r10_bio);
-
- return 0;
-out:
- allow_barrier(conf);
- return -EAGAIN;
-}
-
static bool raid10_make_request(struct mddev *mddev, struct bio *bio)
{
struct r10conf *conf = mddev->private;
@@ -1820,10 +1515,6 @@ static bool raid10_make_request(struct mddev *mddev, struct bio *bio)
if (!md_write_start(mddev, bio))
return false;
- if (unlikely(bio_op(bio) == REQ_OP_DISCARD))
- if (!raid10_handle_discard(mddev, bio))
- return true;
-
/*
* If this request crosses a chunk boundary, we need to split
* it.
@@ -4063,7 +3754,7 @@ static int raid10_run(struct mddev *mddev)
if (mddev->queue) {
blk_queue_max_discard_sectors(mddev->queue,
- UINT_MAX);
+ mddev->chunk_sectors);
blk_queue_max_write_same_sectors(mddev->queue, 0);
blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9);
diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h
index 1461fd55311b..79cd2b7d3128 100644
--- a/drivers/md/raid10.h
+++ b/drivers/md/raid10.h
@@ -179,6 +179,5 @@ enum r10bio_state {
R10BIO_Previous,
/* failfast devices did receive failfast requests. */
R10BIO_FailFast,
- R10BIO_Discard,
};
#endif