Commit 7a87f434 authored by shli@kernel.org's avatar shli@kernel.org Committed by NeilBrown
Browse files

raid5: track overwrite disk count 



Track overwrite disk count, so we can know if a stripe is a full stripe write.

Signed-off-by: default avatarShaohua Li <shli@fusionio.com>
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
parent da41ba65

drivers/md/raid5.c

+13 −1
Original line number Diff line number Diff line
@@ -553,6 +553,7 @@ static void init_stripe(struct stripe_head *sh, sector_t sector, int previous) 
	}

	if (read_seqcount_retry(&conf->gen_lock, seq))

		goto retry;

	sh->overwrite_disks = 0;

	insert_hash(conf, sh);

	sh->cpu = smp_processor_id();

	set_bit(STRIPE_BATCH_READY, &sh->state);
@@ -710,6 +711,12 @@ get_active_stripe(struct r5conf *conf, sector_t sector, 
	return sh;

}



static bool is_full_stripe_write(struct stripe_head *sh)

{

	BUG_ON(sh->overwrite_disks > (sh->disks - sh->raid_conf->max_degraded));

	return sh->overwrite_disks == (sh->disks - sh->raid_conf->max_degraded);

}



/* Determine if 'data_offset' or 'new_data_offset' should be used

 * in this stripe_head.

 */
@@ -1413,6 +1420,7 @@ ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) 
			spin_lock_irq(&sh->stripe_lock);

			chosen = dev->towrite;

			dev->towrite = NULL;

			sh->overwrite_disks = 0;

			BUG_ON(dev->written);

			wbi = dev->written = chosen;

			spin_unlock_irq(&sh->stripe_lock);
@@ -2700,7 +2708,8 @@ static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, 
				sector = bio_end_sector(bi);

		}

		if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS)

			set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags);

			if (!test_and_set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags))

				sh->overwrite_disks++;

	}



	pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
@@ -2772,6 +2781,7 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh, 
		/* fail all writes first */

		bi = sh->dev[i].towrite;

		sh->dev[i].towrite = NULL;

		sh->overwrite_disks = 0;

		spin_unlock_irq(&sh->stripe_lock);

		if (bi)

			bitmap_end = 1;
@@ -4630,12 +4640,14 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi) 
		}

		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)

				continue;

			sh->dev[d].towrite = bi;

			set_bit(R5_OVERWRITE, &sh->dev[d].flags);

			raid5_inc_bi_active_stripes(bi);

			sh->overwrite_disks++;

		}

		spin_unlock_irq(&sh->stripe_lock);

		if (conf->mddev->bitmap) {

drivers/md/raid5.h

+4 −0
Original line number Diff line number Diff line
@@ -210,6 +210,10 @@ struct stripe_head { 
	atomic_t		count;	      /* nr of active thread/requests */

	int			bm_seq;	/* sequence number for bitmap flushes */

	int			disks;		/* disks in stripe */

	int			overwrite_disks; /* total overwrite disks in stripe,

						  * this is only checked when stripe

						  * has STRIPE_BATCH_READY

						  */

	enum check_states	check_state;

	enum reconstruct_states reconstruct_state;

	spinlock_t		stripe_lock;