raid5-cache: fix journal hotadd

PATCH Applied Shaohua Li 2 participants 10 messages Jan 5, 2016 – Jan 6, 2016 MD RAID

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Shaohua Li

author

2016-01-05 21:26 UTC #0 lore raw

cover raid5-cache: fix journal hotadd

Hi Neil,

This patch set fix some issues for journal disk hotadd, mainly for raid array which isn't created with journal support. If there are write IO running in the array when journal disk is adding, the write IO isn't protected by journal (eg, expose write hole issue), but this is unavoidable.

Thanks,
Shaohua

Shaohua Li (4):
raid5-cache: use rcu api to access r5conf->log
raid5-cache: avoid write failure for journal hotadd
raid5-cache: handle flush request for journal hotadd
raid5-cache: handle batch stripe for journal hotadd

 drivers/md/md.c          | 10 +++++++-
 drivers/md/md.h          |  2 ++
 drivers/md/raid5-cache.c | 61 +++++++++++++++++++++++++++++++++++++++---------
 drivers/md/raid5.c       | 20 ++++++++--------
 drivers/md/raid5.h       | 10 ++++----
 5 files changed, 76 insertions(+), 27 deletions(-)

Signature · 1 line

2.4.6

Shaohua Li

author

2016-01-05 21:26 UTC #1 lore raw

PATCH 1/4 raid5-cache: use rcu api to access r5conf->log

If we add journal disk to an array which isn't created with journal, IO might be running in the array. We must be careful about the log checks to make sure log is fully initialized, which is the job of rcu_dereference(). Don't need rcu read lock protection here, as hotremove only happens when there is no write requests.

Signed-off-by Shaohua Li <[email protected]>

---
 drivers/md/raid5-cache.c | 19 +++++++++++++------
 drivers/md/raid5.c       | 20 ++++++++++----------
 drivers/md/raid5.h       | 10 +++++-----
 3 files changed, 28 insertions(+), 21 deletions(-)

drivers/md/raid5-cache.c +13 -6

index d242a36..31e0fad 100644
@@ -438,7 +438,7 @@ static void r5l_wake_reclaim(struct r5l_log *log, sector_t space);
  * running in raid5d, where reclaim could wait for raid5d too (when it flushes
  * data from log to raid disks), so we shouldn't wait for reclaim here
  */
-int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
+int r5l_write_stripe(struct r5conf *conf, struct stripe_head *sh)
 {
 	int write_disks = 0;
 	int data_pages, parity_pages;

@@ -446,6 +446,7 @@ int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
 	int reserve;
 	int i;
 	int ret = 0;
+	struct r5l_log *log = rcu_dereference(conf->log);
 
 	if (!log)
 		return -EAGAIN;

@@ -513,8 +514,9 @@ int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh)
 	return 0;
 }
 
-void r5l_write_stripe_run(struct r5l_log *log)
+void r5l_write_stripe_run(struct r5conf *conf)
 {
+	struct r5l_log *log = rcu_dereference(conf->log);
 	if (!log)
 		return;
 	mutex_lock(&log->io_mutex);

@@ -522,8 +524,10 @@ void r5l_write_stripe_run(struct r5l_log *log)
 	mutex_unlock(&log->io_mutex);
 }
 
-int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio)
+int r5l_handle_flush_request(struct r5conf *conf, struct bio *bio)
 {
+	struct r5l_log *log = ACCESS_ONCE(conf->log);
+
 	if (!log)
 		return -ENODEV;
 	/*

@@ -664,9 +668,10 @@ static void r5l_log_flush_endio(struct bio *bio)
  * only write stripes of an io_unit to raid disks till the io_unit is the first
  * one whose data/parity is in log.
  */
-void r5l_flush_stripe_to_raid(struct r5l_log *log)
+void r5l_flush_stripe_to_raid(struct r5conf *conf)
 {
 	bool do_flush;
+	struct r5l_log *log = rcu_dereference(conf->log);
 
 	if (!log || !log->need_cache_flush)
 		return;

@@ -800,7 +805,7 @@ static void r5l_reclaim_thread(struct md_thread *thread)
 {
 	struct mddev *mddev = thread->mddev;
 	struct r5conf *conf = mddev->private;
-	struct r5l_log *log = conf->log;
+	struct r5l_log *log = rcu_dereference(conf->log);
 
 	if (!log)
 		return;

@@ -820,9 +825,11 @@ static void r5l_wake_reclaim(struct r5l_log *log, sector_t space)
 	md_wakeup_thread(log->reclaim_thread);
 }
 
-void r5l_quiesce(struct r5l_log *log, int state)
+void r5l_quiesce(struct r5conf *conf, int state)
 {
 	struct mddev *mddev;
+	struct r5l_log *log = rcu_dereference(conf->log);
+
 	if (!log || state == 2)
 		return;
 	if (state == 0) {

drivers/md/raid5.c +10 ~~-10~~

index a086014..e74ead1 100644
@@ -757,7 +757,7 @@ static bool stripe_can_batch(struct stripe_head *sh)
 {
 	struct r5conf *conf = sh->raid_conf;
 
-	if (conf->log)
+	if (ACCESS_ONCE(conf->log))
 		return false;
 	return test_bit(STRIPE_BATCH_READY, &sh->state) &&
 		!test_bit(STRIPE_BITMAP_PENDING, &sh->state) &&

@@ -897,7 +897,7 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
 
 	might_sleep();
 
-	if (r5l_write_stripe(conf->log, sh) == 0)
+	if (r5l_write_stripe(conf, sh) == 0)
 		return;
 	for (i = disks; i--; ) {
 		int rw;

@@ -5148,7 +5148,7 @@ static void make_request(struct mddev *mddev, struct bio * bi)
 	bool do_prepare;
 
 	if (unlikely(bi->bi_rw & REQ_FLUSH)) {
-		int ret = r5l_handle_flush_request(conf->log, bi);
+		int ret = r5l_handle_flush_request(conf, bi);
 
 		if (ret == 0)
 			return;

@@ -5751,7 +5751,7 @@ static int handle_active_stripes(struct r5conf *conf, int group,
 				break;
 		if (i == NR_STRIPE_HASH_LOCKS) {
 			spin_unlock_irq(&conf->device_lock);
-			r5l_flush_stripe_to_raid(conf->log);
+			r5l_flush_stripe_to_raid(conf);
 			spin_lock_irq(&conf->device_lock);
 			return batch_size;
 		}

@@ -5762,7 +5762,7 @@ static int handle_active_stripes(struct r5conf *conf, int group,
 	release_inactive_stripe_list(conf, temp_inactive_list,
 				     NR_STRIPE_HASH_LOCKS);
 
-	r5l_flush_stripe_to_raid(conf->log);
+	r5l_flush_stripe_to_raid(conf);
 	if (release_inactive) {
 		spin_lock_irq(&conf->device_lock);
 		return 0;

@@ -5770,7 +5770,7 @@ static int handle_active_stripes(struct r5conf *conf, int group,
 
 	for (i = 0; i < batch_size; i++)
 		handle_stripe(batch[i]);
-	r5l_write_stripe_run(conf->log);
+	r5l_write_stripe_run(conf);
 
 	cond_resched();

@@ -5904,7 +5904,7 @@ static void raid5d(struct md_thread *thread)
 		mutex_unlock(&conf->cache_size_mutex);
 	}
 
-	r5l_flush_stripe_to_raid(conf->log);
+	r5l_flush_stripe_to_raid(conf);
 
 	async_tx_issue_pending_all();
 	blk_finish_plug(&plug);

@@ -7291,7 +7291,7 @@ static int raid5_resize(struct mddev *mddev, sector_t sectors)
 	sector_t newsize;
 	struct r5conf *conf = mddev->private;
 
-	if (conf->log)
+	if (ACCESS_ONCE(conf->log))
 		return -EINVAL;
 	sectors &= ~((sector_t)conf->chunk_sectors - 1);
 	newsize = raid5_size(mddev, sectors, mddev->raid_disks);

@@ -7344,7 +7344,7 @@ static int check_reshape(struct mddev *mddev)
 {
 	struct r5conf *conf = mddev->private;
 
-	if (conf->log)
+	if (ACCESS_ONCE(conf->log))
 		return -EINVAL;
 	if (mddev->delta_disks == 0 &&
 	    mddev->new_layout == mddev->layout &&

@@ -7622,7 +7622,7 @@ static void raid5_quiesce(struct mddev *mddev, int state)
 		unlock_all_device_hash_locks_irq(conf);
 		break;
 	}
-	r5l_quiesce(conf->log, state);
+	r5l_quiesce(conf, state);
 }
 
 static void *raid45_takeover_raid0(struct mddev *mddev, int level)

drivers/md/raid5.h +5 -5

index a415e1c..96969fb 100644
@@ -626,11 +626,11 @@ raid5_get_active_stripe(struct r5conf *conf, sector_t sector,
 			int previous, int noblock, int noquiesce);
 extern int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev);
 extern void r5l_exit_log(struct r5l_log *log);
-extern int r5l_write_stripe(struct r5l_log *log, struct stripe_head *head_sh);
-extern void r5l_write_stripe_run(struct r5l_log *log);
-extern void r5l_flush_stripe_to_raid(struct r5l_log *log);
+extern int r5l_write_stripe(struct r5conf *conf, struct stripe_head *head_sh);
+extern void r5l_write_stripe_run(struct r5conf *conf);
+extern void r5l_flush_stripe_to_raid(struct r5conf *conf);
 extern void r5l_stripe_write_finished(struct stripe_head *sh);
-extern int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio);
-extern void r5l_quiesce(struct r5l_log *log, int state);
+extern int r5l_handle_flush_request(struct r5conf *conf, struct bio *bio);
+extern void r5l_quiesce(struct r5conf *conf, int state);
 extern bool r5l_log_disk_error(struct r5conf *conf);
 #endif

Signature · 1 line

2.4.6

NeilBrown

Applied

2016-01-06 01:04 UTC #2 lore raw

Re: [PATCH 1/4] raid5-cache: use rcu api to access r5conf->log

Quoted 5 lines · Shaohua Li

If we add journal disk to an array which isn't created with journal, IO might be running in the array. We must be careful about the log checks to make sure log is fully initialized, which is the job of rcu_dereference(). Don't need rcu read lock protection here, as hotremove only happens when there is no write requests.

Very sensible, especially as conf->log is set using rcu_assign_ptr().

Applied, thanks
NeilBrown

Shaohua Li

author

2016-01-05 21:26 UTC #3 lore raw

PATCH 2/4 raid5-cache: avoid write failure for journal hotadd

In reply to Shaohua Li

r5l_log_disk_error() will make write request fail if there is no log, but MD_HAS_JOURNAL is set. When we hotadd journal, MD_HAS_JOURNAL is set but the r5l_log isn't fully initialized yet. Adding a new flag to indicate the situation and let r5l_log_disk_error() handle the situation.

Based on Song Liu's original patch

Signed-off-by Shaohua Li <[email protected]>

---
 drivers/md/md.c          | 10 +++++++++-
 drivers/md/md.h          |  2 ++
 drivers/md/raid5-cache.c | 16 +++++++++++++---
 3 files changed, 24 insertions(+), 4 deletions(-)

drivers/md/md.c +9 -1

index c0c3e6d..9f1d609 100644
@@ -6899,8 +6899,16 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode,
 			else if (!(info.state & (1<<MD_DISK_SYNC)))
 				/* Need to clear read-only for this */
 				break;
-			else
+			else {
+				if ((info.state & (1<<MD_DISK_JOURNAL)) &&
+				    !test_bit(MD_HAS_JOURNAL, &mddev->flags))
+					set_bit(MD_JOURNAL_NOT_INITIALIZED,
+						&mddev->flags);
 				err = add_new_disk(mddev, &info);
+				if (err)
+					clear_bit(MD_JOURNAL_NOT_INITIALIZED,
+						&mddev->flags);
+			}
 			goto unlock;
 		}
 		break;

drivers/md/md.h +2 -0

index e16a17c..d18e0d4 100644
@@ -238,6 +238,8 @@ struct mddev {
 #define MD_RELOAD_SB	7	/* Reload the superblock because another node
 				 * updated it.
 				 */
+#define MD_JOURNAL_NOT_INITIALIZED 8 /* hot add a journal, and journal isn't
+				      * ready to use yet */
 
 	int				suspended;
 	atomic_t			active_io;

drivers/md/raid5-cache.c +13 -3

index 31e0fad..5a0f680 100644
@@ -859,9 +859,17 @@ bool r5l_log_disk_error(struct r5conf *conf)
 	rcu_read_lock();
 	log = rcu_dereference(conf->log);
 
-	if (!log)
-		ret = test_bit(MD_HAS_JOURNAL, &conf->mddev->flags);
-	else
+	if (!log) {
+		ret = test_bit(MD_HAS_JOURNAL, &conf->mddev->flags) &&
+		      !test_bit(MD_JOURNAL_NOT_INITIALIZED, &conf->mddev->flags);
+		smp_mb__after_atomic();
+		/*
+		 * r5l_init_log sets ->log first and then clear INITIALIZED, we
+		 * check in reverse order to avoid race condition.
+		 */
+		log = rcu_dereference(conf->log);
+	}
+	if (log)
 		ret = test_bit(Faulty, &log->rdev->flags);
 	rcu_read_unlock();
 	return ret;

@@ -1242,6 +1250,8 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
 		goto error;
 
 	rcu_assign_pointer(conf->log, log);
+	smp_mb__before_atomic();
+	clear_bit(MD_JOURNAL_NOT_INITIALIZED, &conf->mddev->flags);
 	return 0;
 
 error:

Signature · 1 line

2.4.6

NeilBrown

2016-01-06 01:03 UTC #4 lore raw

Re: [PATCH 2/4] raid5-cache: avoid write failure for journal hotadd

Quoted 85 lines · Shaohua Li

Based on Song Liu's original patch

Signed-off-by Shaohua Li <[email protected]>

---
 drivers/md/md.c          | 10 +++++++++-
 drivers/md/md.h          |  2 ++
 drivers/md/raid5-cache.c | 16 +++++++++++++---
 3 files changed, 24 insertions(+), 4 deletions(-)

drivers/md/md.c +9 -1

index c0c3e6d..9f1d609 100644
@@ -6899,8 +6899,16 @@ static int md_ioctl(struct block_device *bdev, fmode_t mode,
 			else if (!(info.state & (1<<MD_DISK_SYNC)))
 				/* Need to clear read-only for this */
 				break;
-			else
+			else {
+				if ((info.state & (1<<MD_DISK_JOURNAL)) &&
+				    !test_bit(MD_HAS_JOURNAL, &mddev->flags))
+					set_bit(MD_JOURNAL_NOT_INITIALIZED,
+						&mddev->flags);
 				err = add_new_disk(mddev, &info);
+				if (err)
+					clear_bit(MD_JOURNAL_NOT_INITIALIZED,
+						&mddev->flags);
+			}
 			goto unlock;
 		}
 		break;

drivers/md/md.h +2 -0

index e16a17c..d18e0d4 100644
@@ -238,6 +238,8 @@ struct mddev {
 #define MD_RELOAD_SB	7	/* Reload the superblock because another node
 				 * updated it.
 				 */
+#define MD_JOURNAL_NOT_INITIALIZED 8 /* hot add a journal, and journal isn't
+				      * ready to use yet */
 
 	int				suspended;
 	atomic_t			active_io;

drivers/md/raid5-cache.c +13 -3

index 31e0fad..5a0f680 100644
@@ -859,9 +859,17 @@ bool r5l_log_disk_error(struct r5conf *conf)
 	rcu_read_lock();
 	log = rcu_dereference(conf->log);
 
-	if (!log)
-		ret = test_bit(MD_HAS_JOURNAL, &conf->mddev->flags);
-	else
+	if (!log) {
+		ret = test_bit(MD_HAS_JOURNAL, &conf->mddev->flags) &&
+		      !test_bit(MD_JOURNAL_NOT_INITIALIZED, &conf->mddev->flags);
+		smp_mb__after_atomic();
+		/*
+		 * r5l_init_log sets ->log first and then clear INITIALIZED, we
+		 * check in reverse order to avoid race condition.
+		 */
+		log = rcu_dereference(conf->log);
+	}
+	if (log)
 		ret = test_bit(Faulty, &log->rdev->flags);
 	rcu_read_unlock();
 	return ret;

@@ -1242,6 +1250,8 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
 		goto error;
 
 	rcu_assign_pointer(conf->log, log);
+	smp_mb__before_atomic();
+	clear_bit(MD_JOURNAL_NOT_INITIALIZED, &conf->mddev->flags);
 	return 0;
 
 error:

Signature · 1 line

2.4.6

I don't feel at all comfortable about this.
Having one flag saying "there is a journal" and another saying "actually, no there isn't" just isn't very clean.

So I wondered "why is MD_HAS_JOURNAL set so early", and discovered it being set in super_1_validate() - but in the wrong place.

super_1_validate should only make changes the mddev when mddev->raid_disks is zero. In that case all the array details are initialised from the metadata.
Other calls to super_1_validate should validate that the new metadata matches mddev, and may set some details in 'rdev'.
So:

			if (mddev->recovery_cp == MaxSector)
				set_bit(MD_JOURNAL_CLEAN, &mddev->flags);
and
		if (le32_to_cpu(sb->feature_map) & MD_FEATURE_JOURNAL)
			set_bit(MD_HAS_JOURNAL, &mddev->flags);

don't fit the pattern.

These should be moved to the "mddev->raid_disks == 0" section of super_1_validate.

Then when a journal is hot-added, the MD_HAS_JOURNAL flag should be set once the journal is actually active.

Thanks,
NeilBrown

Shaohua Li

author

2016-01-05 21:26 UTC #5 lore raw

PATCH 3/4 raid5-cache: handle flush request for journal hotadd

In reply to Shaohua Li

When we hotadd journal for array which isn't created with journal, the array might be running write requests. Such writes aren't protected by journal yet, so we can't skip disk flush. There is no easy way to know when all such writes are finished, but the time should be enough after reclaim runs once.

Signed-off-by Shaohua Li <[email protected]>

---
 drivers/md/raid5-cache.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

drivers/md/raid5-cache.c +24 -2

index 5a0f680..fcda2d2 100644
@@ -97,6 +97,7 @@ struct r5l_log {
 
 	bool need_cache_flush;
 	bool in_teardown;
+	bool force_flush_all_disks;
 };
 
 /*

@@ -526,10 +527,27 @@ void r5l_write_stripe_run(struct r5conf *conf)
 
 int r5l_handle_flush_request(struct r5conf *conf, struct bio *bio)
 {
-	struct r5l_log *log = ACCESS_ONCE(conf->log);
+	struct r5l_log *log;
 
-	if (!log)
+	/* raid5_remove_disk writes_pending check isn't helpful for flush */
+	rcu_read_lock();
+	log = rcu_dereference(conf->log);
+	if (!log) {
+		rcu_read_unlock();
 		return -ENODEV;
+	}
+
+	/*
+	 * If we add journal to array without journal before, the array might
+	 * run write requests before journal runs. such requests are not
+	 * protected by journal, so we can't skip flush.
+	 */
+	if (log->force_flush_all_disks) {
+		rcu_read_unlock();
+		md_flush_request(log->rdev->mddev, bio);
+		return 0;
+	}
+	rcu_read_unlock();
 	/*
 	 * we flush log disk cache first, then write stripe data to raid disks.
 	 * So if bio is finished, the log disk cache is flushed already. The

@@ -798,6 +816,8 @@ static void r5l_do_reclaim(struct r5l_log *log)
 	log->last_cp_seq = next_cp_seq;
 	mutex_unlock(&log->io_mutex);
 
+	log->force_flush_all_disks = false;
+
 	r5l_run_no_space_stripes(log);
 }

@@ -1246,6 +1266,8 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
 	INIT_LIST_HEAD(&log->no_space_stripes);
 	spin_lock_init(&log->no_space_stripes_lock);
 
+	if (test_bit(MD_JOURNAL_NOT_INITIALIZED, &conf->mddev->flags))
+		log->force_flush_all_disks = true;
 	if (r5l_load_log(log))
 		goto error;

Signature · 1 line

2.4.6

NeilBrown

2016-01-06 01:12 UTC #6 lore raw

Re: [PATCH 3/4] raid5-cache: handle flush request for journal hotadd

Quoted 5 lines · Shaohua Li

When we hotadd journal for array which isn't created with journal, the array might be running write requests. Such writes aren't protected by journal yet, so we can't skip disk flush. There is no easy way to know when all such writes are finished, but the time should be enough after reclaim runs once.

There is an easy way to know when such writes are finished. Call mddev_suspend(mddev). This is used for the more intrusive reconfiguration such as initiating a reshape.
I think it would be perfectly appropriate to
call mddev_suspend()
attach the journal
call mddev_resume()

Thanks,
NeilBrown

Shaohua Li

author

2016-01-06 01:47 UTC #7 lore raw

Re: [PATCH 3/4] raid5-cache: handle flush request for journal hotadd

Quoted 8 lines · NeilBrown

Quoted 5 lines · Shaohua Li
When we hotadd journal for array which isn't created with journal, the array might be running write requests. Such writes aren't protected by journal yet, so we can't skip disk flush. There is no easy way to know when all such writes are finished, but the time should be enough after reclaim runs once.

Quoted 7 lines

There is an easy way to know when such writes are finished. Call mddev_suspend(mddev). This is used for the more intrusive reconfiguration such as initiating a reshape.
I think it would be perfectly appropriate to
call mddev_suspend()
attach the journal
call mddev_resume()

hot add/remove disk is called in raid5d, we can't wait IO there. mddev_suspend() will wait IO. So we can't call mddev_suspend()

Thanks,
Shaohua

NeilBrown

2016-01-06 02:07 UTC #8 lore raw

Re: [PATCH 3/4] raid5-cache: handle flush request for journal hotadd

Quoted 17 lines · Shaohua Li

Quoted 8 lines · NeilBrown
Quoted 5 lines · Shaohua Li
When we hotadd journal for array which isn't created with journal, the array might be running write requests. Such writes aren't protected by journal yet, so we can't skip disk flush. There is no easy way to know when all such writes are finished, but the time should be enough after reclaim runs once.
Quoted 7 lines
There is an easy way to know when such writes are finished. Call mddev_suspend(mddev). This is used for the more intrusive reconfiguration such as initiating a reshape.
I think it would be perfectly appropriate to
call mddev_suspend()
attach the journal
call mddev_resume()

Quoted 2 lines

hot add/remove disk is called in raid5d, we can't wait IO there. mddev_suspend() will wait IO. So we can't call mddev_suspend()

Fair point. I wonder if it should be though.

Activating a spare is a very different thing to activating a journal. Activating a spare is just one small step on the way from being degraded to being optimal.
Activating a spare is a distinct change in how the array behaves, not unlike adding a bitmap.

So I think that adding a journal should happen a lot like adding a bitmap.
When you write "journal" to the 'state' file, or call ADD_NEW_DISK with MD_DISK_JOURNAL set, ->hot_add_disk() should be called directly, a bit like add_bound_rdev() does when adding a device to a 'linear' array.

Having remove_and_add_spares() add a journal certainly doesn't seem like a good idea.

Thanks,
NeilBrown

Shaohua Li

author

2016-01-05 21:26 UTC #9 lore raw

PATCH 4/4 raid5-cache: handle batch stripe for journal hotadd

In reply to Shaohua Li

Journal doesn't support batch stripe. If journal is hotadded, there might be pending requests which are already batched. When journal is enabled, such requests should be skipped.

Signed-off-by Shaohua Li <[email protected]>

---
 drivers/md/raid5-cache.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

drivers/md/raid5-cache.c +1 -1

index fcda2d2..560de57 100644
@@ -453,7 +453,7 @@ int r5l_write_stripe(struct r5conf *conf, struct stripe_head *sh)
 		return -EAGAIN;
 	/* Don't support stripe batch */
 	if (sh->log_io || !test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags) ||
-	    test_bit(STRIPE_SYNCING, &sh->state)) {
+	    test_bit(STRIPE_SYNCING, &sh->state) || sh->batch_head) {
 		/* the stripe is written to log, we start writing it to raid */
 		clear_bit(STRIPE_LOG_TRAPPED, &sh->state);
 		return -EAGAIN;

Signature · 1 line

2.4.6