1 files changed, 82 insertions, 75 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index c14cf2410365..dc2ea636d173 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2337,7 +2337,7 @@ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
 		for (i = disks; i--; ) {
 			struct r5dev *dev = &sh->dev[i];
 			if (test_and_clear_bit(R5_Overlap, &dev->flags))
-				wake_up(&sh->raid_conf->wait_for_overlap);
+				wake_up_bit(&dev->flags, R5_Overlap);
 		}
 	}
 	local_unlock(&conf->percpu->lock);
@@ -3473,7 +3473,7 @@ static bool stripe_bio_overlaps(struct stripe_head *sh, struct bio *bi,
 		 * With PPL only writes to consecutive data chunks within a
 		 * stripe are allowed because for a single stripe_head we can
 		 * only have one PPL entry at a time, which describes one data
-		 * range. Not really an overlap, but wait_for_overlap can be
+		 * range. Not really an overlap, but R5_Overlap can be
 		 * used to handle this.
 		 */
 		sector_t sector;
@@ -3563,8 +3563,8 @@ static void __add_stripe_bio(struct stripe_head *sh, struct bio *bi,
 		 */
 		set_bit(STRIPE_BITMAP_PENDING, &sh->state);
 		spin_unlock_irq(&sh->stripe_lock);
-		md_bitmap_startwrite(conf->mddev->bitmap, sh->sector,
-				     RAID5_STRIPE_SECTORS(conf), 0);
+		conf->mddev->bitmap_ops->startwrite(conf->mddev, sh->sector,
+					RAID5_STRIPE_SECTORS(conf), false);
 		spin_lock_irq(&sh->stripe_lock);
 		clear_bit(STRIPE_BITMAP_PENDING, &sh->state);
 		if (!sh->batch_head) {
@@ -3652,7 +3652,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 		log_stripe_write_finished(sh);
 
 		if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
-			wake_up(&conf->wait_for_overlap);
+			wake_up_bit(&sh->dev[i].flags, R5_Overlap);
 
 		while (bi && bi->bi_iter.bi_sector <
 			sh->dev[i].sector + RAID5_STRIPE_SECTORS(conf)) {
@@ -3663,8 +3663,9 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 			bi = nextbi;
 		}
 		if (bitmap_end)
-			md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
-					   RAID5_STRIPE_SECTORS(conf), 0, 0);
+			conf->mddev->bitmap_ops->endwrite(conf->mddev,
+					sh->sector, RAID5_STRIPE_SECTORS(conf),
+					false, false);
 		bitmap_end = 0;
 		/* and fail all 'written' */
 		bi = sh->dev[i].written;
@@ -3696,7 +3697,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 			sh->dev[i].toread = NULL;
 			spin_unlock_irq(&sh->stripe_lock);
 			if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
-				wake_up(&conf->wait_for_overlap);
+				wake_up_bit(&sh->dev[i].flags, R5_Overlap);
 			if (bi)
 				s->to_read--;
 			while (bi && bi->bi_iter.bi_sector <
@@ -3709,8 +3710,9 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
 			}
 		}
 		if (bitmap_end)
-			md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
-					   RAID5_STRIPE_SECTORS(conf), 0, 0);
+			conf->mddev->bitmap_ops->endwrite(conf->mddev,
+					sh->sector, RAID5_STRIPE_SECTORS(conf),
+					false, false);
 		/* If we were in the middle of a write the parity block might
 		 * still be locked - so just clear all R5_LOCKED flags
 		 */
@@ -3734,7 +3736,7 @@ handle_failed_sync(struct r5conf *conf, struct stripe_head *sh,
 	BUG_ON(sh->batch_head);
 	clear_bit(STRIPE_SYNCING, &sh->state);
 	if (test_and_clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags))
-		wake_up(&conf->wait_for_overlap);
+		wake_up_bit(&sh->dev[sh->pd_idx].flags, R5_Overlap);
 	s->syncing = 0;
 	s->replacing = 0;
 	/* There is nothing more to do for sync/check/repair.
@@ -4059,10 +4061,10 @@ returnbi:
 					bio_endio(wbi);
 					wbi = wbi2;
 				}
-				md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
-						   RAID5_STRIPE_SECTORS(conf),
-						   !test_bit(STRIPE_DEGRADED, &sh->state),
-						   0);
+				conf->mddev->bitmap_ops->endwrite(conf->mddev,
+					sh->sector, RAID5_STRIPE_SECTORS(conf),
+					!test_bit(STRIPE_DEGRADED, &sh->state),
+					false);
 				if (head_sh->batch_head) {
 					sh = list_first_entry(&sh->batch_list,
 							      struct stripe_head,
@@ -4875,7 +4877,6 @@ static void break_stripe_batch_list(struct stripe_head *head_sh,
 {
 	struct stripe_head *sh, *next;
 	int i;
-	int do_wakeup = 0;
 
 	list_for_each_entry_safe(sh, next, &head_sh->batch_list, batch_list) {
 
@@ -4911,7 +4912,7 @@ static void break_stripe_batch_list(struct stripe_head *head_sh,
 		spin_unlock_irq(&sh->stripe_lock);
 		for (i = 0; i < sh->disks; i++) {
 			if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
-				do_wakeup = 1;
+				wake_up_bit(&sh->dev[i].flags, R5_Overlap);
 			sh->dev[i].flags = head_sh->dev[i].flags &
 				(~((1 << R5_WriteError) | (1 << R5_Overlap)));
 		}
@@ -4925,12 +4926,9 @@ static void break_stripe_batch_list(struct stripe_head *head_sh,
 	spin_unlock_irq(&head_sh->stripe_lock);
 	for (i = 0; i < head_sh->disks; i++)
 		if (test_and_clear_bit(R5_Overlap, &head_sh->dev[i].flags))
-			do_wakeup = 1;
+			wake_up_bit(&head_sh->dev[i].flags, R5_Overlap);
 	if (head_sh->state & handle_flags)
 		set_bit(STRIPE_HANDLE, &head_sh->state);
-
-	if (do_wakeup)
-		wake_up(&head_sh->raid_conf->wait_for_overlap);
 }
 
 static void handle_stripe(struct stripe_head *sh)
@@ -5196,7 +5194,7 @@ static void handle_stripe(struct stripe_head *sh)
 		md_done_sync(conf->mddev, RAID5_STRIPE_SECTORS(conf), 1);
 		clear_bit(STRIPE_SYNCING, &sh->state);
 		if (test_and_clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags))
-			wake_up(&conf->wait_for_overlap);
+			wake_up_bit(&sh->dev[sh->pd_idx].flags, R5_Overlap);
 	}
 
 	/* If the failed drives are just a ReadError, then we might need
@@ -5259,7 +5257,7 @@ static void handle_stripe(struct stripe_head *sh)
 	} else if (s.expanded && !sh->reconstruct_state && s.locked == 0) {
 		clear_bit(STRIPE_EXPAND_READY, &sh->state);
 		atomic_dec(&conf->reshape_stripes);
-		wake_up(&conf->wait_for_overlap);
+		wake_up(&conf->wait_for_reshape);
 		md_done_sync(conf->mddev, RAID5_STRIPE_SECTORS(conf), 1);
 	}
 
@@ -5753,12 +5751,11 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi)
 		int d;
 	again:
 		sh = raid5_get_active_stripe(conf, NULL, logical_sector, 0);
-		prepare_to_wait(&conf->wait_for_overlap, &w,
-				TASK_UNINTERRUPTIBLE);
 		set_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags);
 		if (test_bit(STRIPE_SYNCING, &sh->state)) {
 			raid5_release_stripe(sh);
-			schedule();
+			wait_on_bit(&sh->dev[sh->pd_idx].flags, R5_Overlap,
+				    TASK_UNINTERRUPTIBLE);
 			goto again;
 		}
 		clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags);
@@ -5770,12 +5767,12 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi)
 				set_bit(R5_Overlap, &sh->dev[d].flags);
 				spin_unlock_irq(&sh->stripe_lock);
 				raid5_release_stripe(sh);
-				schedule();
+				wait_on_bit(&sh->dev[d].flags, R5_Overlap,
+					    TASK_UNINTERRUPTIBLE);
 				goto again;
 			}
 		}
 		set_bit(STRIPE_DISCARD, &sh->state);
-		finish_wait(&conf->wait_for_overlap, &w);
 		sh->overwrite_disks = 0;
 		for (d = 0; d < conf->raid_disks; d++) {
 			if (d == sh->pd_idx || d == sh->qd_idx)
@@ -5788,13 +5785,10 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi)
 		}
 		spin_unlock_irq(&sh->stripe_lock);
 		if (conf->mddev->bitmap) {
-			for (d = 0;
-			     d < conf->raid_disks - conf->max_degraded;
+			for (d = 0; d < conf->raid_disks - conf->max_degraded;
 			     d++)
-				md_bitmap_startwrite(mddev->bitmap,
-						     sh->sector,
-						     RAID5_STRIPE_SECTORS(conf),
-						     0);
+				mddev->bitmap_ops->startwrite(mddev, sh->sector,
+					RAID5_STRIPE_SECTORS(conf), false);
 			sh->bm_seq = conf->seq_flush + 1;
 			set_bit(STRIPE_BIT_DELAY, &sh->state);
 		}
@@ -5855,7 +5849,6 @@ static int add_all_stripe_bios(struct r5conf *conf,
 		struct bio *bi, int forwrite, int previous)
 {
 	int dd_idx;
-	int ret = 1;
 
 	spin_lock_irq(&sh->stripe_lock);
 
@@ -5871,14 +5864,19 @@ static int add_all_stripe_bios(struct r5conf *conf,
 
 		if (stripe_bio_overlaps(sh, bi, dd_idx, forwrite)) {
 			set_bit(R5_Overlap, &dev->flags);
-			ret = 0;
-			continue;
+			spin_unlock_irq(&sh->stripe_lock);
+			raid5_release_stripe(sh);
+			/* release batch_last before wait to avoid risk of deadlock */
+			if (ctx->batch_last) {
+				raid5_release_stripe(ctx->batch_last);
+				ctx->batch_last = NULL;
+			}
+			md_wakeup_thread(conf->mddev->thread);
+			wait_on_bit(&dev->flags, R5_Overlap, TASK_UNINTERRUPTIBLE);
+			return 0;
 		}
 	}
 
-	if (!ret)
-		goto out;
-
 	for (dd_idx = 0; dd_idx < sh->disks; dd_idx++) {
 		struct r5dev *dev = &sh->dev[dd_idx];
 
@@ -5894,9 +5892,8 @@ static int add_all_stripe_bios(struct r5conf *conf,
 			  RAID5_STRIPE_SHIFT(conf), ctx->sectors_to_do);
 	}
 
-out:
 	spin_unlock_irq(&sh->stripe_lock);
-	return ret;
+	return 1;
 }
 
 enum reshape_loc {
@@ -5992,17 +5989,17 @@ static enum stripe_result make_stripe_request(struct mddev *mddev,
 		goto out_release;
 	}
 
-	if (test_bit(STRIPE_EXPANDING, &sh->state) ||
-	    !add_all_stripe_bios(conf, ctx, sh, bi, rw, previous)) {
-		/*
-		 * Stripe is busy expanding or add failed due to
-		 * overlap. Flush everything and wait a while.
-		 */
+	if (test_bit(STRIPE_EXPANDING, &sh->state)) {
 		md_wakeup_thread(mddev->thread);
 		ret = STRIPE_SCHEDULE_AND_RETRY;
 		goto out_release;
 	}
 
+	if (!add_all_stripe_bios(conf, ctx, sh, bi, rw, previous)) {
+		ret = STRIPE_RETRY;
+		goto out;
+	}
+
 	if (stripe_can_batch(sh)) {
 		stripe_add_to_batch_list(conf, sh, ctx->batch_last);
 		if (ctx->batch_last)
@@ -6073,6 +6070,7 @@ static sector_t raid5_bio_lowest_chunk_sector(struct r5conf *conf,
 static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 {
 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
+	bool on_wq;
 	struct r5conf *conf = mddev->private;
 	sector_t logical_sector;
 	struct stripe_request_ctx ctx = {};
@@ -6146,11 +6144,15 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 	 * sequential IO pattern. We don't bother with the optimization when
 	 * reshaping as the performance benefit is not worth the complexity.
 	 */
-	if (likely(conf->reshape_progress == MaxSector))
+	if (likely(conf->reshape_progress == MaxSector)) {
 		logical_sector = raid5_bio_lowest_chunk_sector(conf, bi);
+		on_wq = false;
+	} else {
+		add_wait_queue(&conf->wait_for_reshape, &wait);
+		on_wq = true;
+	}
 	s = (logical_sector - ctx.first_sector) >> RAID5_STRIPE_SHIFT(conf);
 
-	add_wait_queue(&conf->wait_for_overlap, &wait);
 	while (1) {
 		res = make_stripe_request(mddev, conf, &ctx, logical_sector,
 					  bi);
@@ -6161,6 +6163,7 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 			continue;
 
 		if (res == STRIPE_SCHEDULE_AND_RETRY) {
+			WARN_ON_ONCE(!on_wq);
 			/*
 			 * Must release the reference to batch_last before
 			 * scheduling and waiting for work to be done,
@@ -6185,7 +6188,8 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 		logical_sector = ctx.first_sector +
 			(s << RAID5_STRIPE_SHIFT(conf));
 	}
-	remove_wait_queue(&conf->wait_for_overlap, &wait);
+	if (unlikely(on_wq))
+		remove_wait_queue(&conf->wait_for_reshape, &wait);
 
 	if (ctx.batch_last)
 		raid5_release_stripe(ctx.batch_last);
@@ -6338,7 +6342,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
 	     : (safepos < writepos && readpos > writepos)) ||
 	    time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) {
 		/* Cannot proceed until we've updated the superblock... */
-		wait_event(conf->wait_for_overlap,
+		wait_event(conf->wait_for_reshape,
 			   atomic_read(&conf->reshape_stripes)==0
 			   || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
 		if (atomic_read(&conf->reshape_stripes) != 0)
@@ -6364,7 +6368,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk
 		spin_lock_irq(&conf->device_lock);
 		conf->reshape_safe = mddev->reshape_position;
 		spin_unlock_irq(&conf->device_lock);
-		wake_up(&conf->wait_for_overlap);
+		wake_up(&conf->wait_for_reshape);
 		sysfs_notify_dirent_safe(mddev->sysfs_completed);
 	}
 
@@ -6447,7 +6451,7 @@ finish:
 	    (sector_nr - mddev->curr_resync_completed) * 2
 	    >= mddev->resync_max - mddev->curr_resync_completed) {
 		/* Cannot proceed until we've updated the superblock... */
-		wait_event(conf->wait_for_overlap,
+		wait_event(conf->wait_for_reshape,
 			   atomic_read(&conf->reshape_stripes) == 0
 			   || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
 		if (atomic_read(&conf->reshape_stripes) != 0)
@@ -6473,7 +6477,7 @@ finish:
 		spin_lock_irq(&conf->device_lock);
 		conf->reshape_safe = mddev->reshape_position;
 		spin_unlock_irq(&conf->device_lock);
-		wake_up(&conf->wait_for_overlap);
+		wake_up(&conf->wait_for_reshape);
 		sysfs_notify_dirent_safe(mddev->sysfs_completed);
 	}
 ret:
@@ -6486,7 +6490,7 @@ static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_n
 	struct r5conf *conf = mddev->private;
 	struct stripe_head *sh;
 	sector_t sync_blocks;
-	int still_degraded = 0;
+	bool still_degraded = false;
 	int i;
 
 	if (sector_nr >= max_sector) {
@@ -6498,17 +6502,17 @@ static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_n
 		}
 
 		if (mddev->curr_resync < max_sector) /* aborted */
-			md_bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
-					   &sync_blocks, 1);
+			mddev->bitmap_ops->end_sync(mddev, mddev->curr_resync,
+						    &sync_blocks);
 		else /* completed sync */
 			conf->fullsync = 0;
-		md_bitmap_close_sync(mddev->bitmap);
+		mddev->bitmap_ops->close_sync(mddev);
 
 		return 0;
 	}
 
 	/* Allow raid5_quiesce to complete */
-	wait_event(conf->wait_for_overlap, conf->quiesce != 2);
+	wait_event(conf->wait_for_reshape, conf->quiesce != 2);
 
 	if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
 		return reshape_request(mddev, sector_nr, skipped);
@@ -6531,7 +6535,8 @@ static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_n
 	}
 	if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
 	    !conf->fullsync &&
-	    !md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
+	    !mddev->bitmap_ops->start_sync(mddev, sector_nr, &sync_blocks,
+					   true) &&
 	    sync_blocks >= RAID5_STRIPE_SECTORS(conf)) {
 		/* we can skip this block, and probably more */
 		do_div(sync_blocks, RAID5_STRIPE_SECTORS(conf));
@@ -6540,7 +6545,7 @@ static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_n
 		return sync_blocks * RAID5_STRIPE_SECTORS(conf);
 	}
 
-	md_bitmap_cond_end_sync(mddev->bitmap, sector_nr, false);
+	mddev->bitmap_ops->cond_end_sync(mddev, sector_nr, false);
 
 	sh = raid5_get_active_stripe(conf, NULL, sector_nr,
 				     R5_GAS_NOBLOCK);
@@ -6559,10 +6564,11 @@ static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_n
 		struct md_rdev *rdev = conf->disks[i].rdev;
 
 		if (rdev == NULL || test_bit(Faulty, &rdev->flags))
-			still_degraded = 1;
+			still_degraded = true;
 	}
 
-	md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded);
+	mddev->bitmap_ops->start_sync(mddev, sector_nr, &sync_blocks,
+				      still_degraded);
 
 	set_bit(STRIPE_SYNC_REQUESTED, &sh->state);
 	set_bit(STRIPE_HANDLE, &sh->state);
@@ -6767,7 +6773,7 @@ static void raid5d(struct md_thread *thread)
 			/* Now is a good time to flush some bitmap updates */
 			conf->seq_flush++;
 			spin_unlock_irq(&conf->device_lock);
-			md_bitmap_unplug(mddev->bitmap);
+			mddev->bitmap_ops->unplug(mddev, true);
 			spin_lock_irq(&conf->device_lock);
 			conf->seq_write = conf->seq_flush;
 			activate_bit_delay(conf, conf->temp_inactive_list);
@@ -7492,7 +7498,7 @@ static struct r5conf *setup_conf(struct mddev *mddev)
 
 	init_waitqueue_head(&conf->wait_for_quiescent);
 	init_waitqueue_head(&conf->wait_for_stripe);
-	init_waitqueue_head(&conf->wait_for_overlap);
+	init_waitqueue_head(&conf->wait_for_reshape);
 	INIT_LIST_HEAD(&conf->handle_list);
 	INIT_LIST_HEAD(&conf->loprio_list);
 	INIT_LIST_HEAD(&conf->hold_list);
@@ -8312,6 +8318,7 @@ static int raid5_resize(struct mddev *mddev, sector_t sectors)
 	 */
 	sector_t newsize;
 	struct r5conf *conf = mddev->private;
+	int ret;
 
 	if (raid5_has_log(conf) || raid5_has_ppl(conf))
 		return -EINVAL;
@@ -8320,11 +8327,11 @@ static int raid5_resize(struct mddev *mddev, sector_t sectors)
 	if (mddev->external_size &&
 	    mddev->array_sectors > newsize)
 		return -EINVAL;
-	if (mddev->bitmap) {
-		int ret = md_bitmap_resize(mddev->bitmap, sectors, 0, 0);
-		if (ret)
-			return ret;
-	}
+
+	ret = mddev->bitmap_ops->resize(mddev, sectors, 0, false);
+	if (ret)
+		return ret;
+
 	md_set_array_sectors(mddev, newsize);
 	if (sectors > mddev->dev_sectors &&
 	    mddev->recovery_cp > mddev->dev_sectors) {
@@ -8550,7 +8557,7 @@ static void end_reshape(struct r5conf *conf)
 			    !test_bit(In_sync, &rdev->flags))
 				rdev->recovery_offset = MaxSector;
 		spin_unlock_irq(&conf->device_lock);
-		wake_up(&conf->wait_for_overlap);
+		wake_up(&conf->wait_for_reshape);
 
 		mddev_update_io_opt(conf->mddev,
 			conf->raid_disks - conf->max_degraded);
@@ -8614,13 +8621,13 @@ static void raid5_quiesce(struct mddev *mddev, int quiesce)
 		conf->quiesce = 1;
 		unlock_all_device_hash_locks_irq(conf);
 		/* allow reshape to continue */
-		wake_up(&conf->wait_for_overlap);
+		wake_up(&conf->wait_for_reshape);
 	} else {
 		/* re-enable writes */
 		lock_all_device_hash_locks_irq(conf);
 		conf->quiesce = 0;
 		wake_up(&conf->wait_for_quiescent);
-		wake_up(&conf->wait_for_overlap);
+		wake_up(&conf->wait_for_reshape);
 		unlock_all_device_hash_locks_irq(conf);
 	}
 	log_quiesce(conf, quiesce);
@@ -8939,7 +8946,7 @@ static void raid5_prepare_suspend(struct mddev *mddev)
 {
 	struct r5conf *conf = mddev->private;
 
-	wake_up(&conf->wait_for_overlap);
+	wake_up(&conf->wait_for_reshape);
 }
 
 static struct md_personality raid6_personality =