Commit 4184153f authored by Mikulas Patocka's avatar Mikulas Patocka Committed by Alasdair G Kergon
Browse files

dm raid1: support flush 



Flush support for dm-raid1.

When it receives an empty barrier, submit it to all the devices via dm-io.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
parent f1e53987

drivers/md/dm-raid1.c

+11 −2
Original line number Diff line number Diff line
@@ -396,6 +396,8 @@ static int mirror_available(struct mirror_set *ms, struct bio *bio) 
 */

static sector_t map_sector(struct mirror *m, struct bio *bio)

{

	if (unlikely(!bio->bi_size))

		return 0;

	return m->offset + (bio->bi_sector - m->ms->ti->begin);

}
@@ -562,7 +564,7 @@ static void do_write(struct mirror_set *ms, struct bio *bio) 
	struct dm_io_region io[ms->nr_mirrors], *dest = io;

	struct mirror *m;

	struct dm_io_request io_req = {

		.bi_rw = WRITE,

		.bi_rw = WRITE | (bio->bi_rw & WRITE_BARRIER),

		.mem.type = DM_IO_BVEC,

		.mem.ptr.bvec = bio->bi_io_vec + bio->bi_idx,

		.notify.fn = write_callback,
@@ -603,6 +605,11 @@ static void do_writes(struct mirror_set *ms, struct bio_list *writes) 
	bio_list_init(&requeue);



	while ((bio = bio_list_pop(writes))) {

		if (unlikely(bio_empty_barrier(bio))) {

			bio_list_add(&sync, bio);

			continue;

		}



		region = dm_rh_bio_to_region(ms->rh, bio);



		if (log->type->is_remote_recovering &&
@@ -995,6 +1002,7 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv) 


	ti->private = ms;

	ti->split_io = dm_rh_get_region_size(ms->rh);

	ti->num_flush_requests = 1;



	ms->kmirrord_wq = create_singlethread_workqueue("kmirrord");

	if (!ms->kmirrord_wq) {
@@ -1122,6 +1130,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, 
	 * We need to dec pending if this was a write.

	 */

	if (rw == WRITE) {

		if (likely(!bio_empty_barrier(bio)))

			dm_rh_dec(ms->rh, map_context->ll);

		return error;

	}

drivers/md/dm-region-hash.c

+23 −2
Original line number Diff line number Diff line
@@ -79,6 +79,11 @@ struct dm_region_hash { 
	struct list_head recovered_regions;

	struct list_head failed_recovered_regions;



	/*

	 * If there was a barrier failure no regions can be marked clean.

	 */

	int barrier_failure;



	void *context;

	sector_t target_begin;
@@ -211,6 +216,7 @@ struct dm_region_hash *dm_region_hash_create( 
	INIT_LIST_HEAD(&rh->quiesced_regions);

	INIT_LIST_HEAD(&rh->recovered_regions);

	INIT_LIST_HEAD(&rh->failed_recovered_regions);

	rh->barrier_failure = 0;



	rh->region_pool = mempool_create_kmalloc_pool(MIN_REGIONS,

						      sizeof(struct dm_region));
@@ -395,6 +401,11 @@ void dm_rh_mark_nosync(struct dm_region_hash *rh, 
	region_t region = dm_rh_bio_to_region(rh, bio);

	int recovering = 0;



	if (bio_empty_barrier(bio)) {

		rh->barrier_failure = 1;

		return;

	}



	/* We must inform the log that the sync count has changed. */

	log->type->set_region_sync(log, region, 0);
@@ -515,9 +526,12 @@ void dm_rh_inc_pending(struct dm_region_hash *rh, struct bio_list *bios) 
{

	struct bio *bio;



	for (bio = bios->head; bio; bio = bio->bi_next)

	for (bio = bios->head; bio; bio = bio->bi_next) {

		if (bio_empty_barrier(bio))

			continue;

		rh_inc(rh, dm_rh_bio_to_region(rh, bio));

	}

}

EXPORT_SYMBOL_GPL(dm_rh_inc_pending);



void dm_rh_dec(struct dm_region_hash *rh, region_t region)
@@ -544,7 +558,14 @@ void dm_rh_dec(struct dm_region_hash *rh, region_t region) 
		 */



		/* do nothing for DM_RH_NOSYNC */

		if (reg->state == DM_RH_RECOVERING) {

		if (unlikely(rh->barrier_failure)) {

			/*

			 * If a write barrier failed some time ago, we

			 * don't know whether or not this write made it

			 * to the disk, so we must resync the device.

			 */

			reg->state = DM_RH_NOSYNC;

		} else if (reg->state == DM_RH_RECOVERING) {

			list_add_tail(&reg->list, &rh->quiesced_regions);

		} else if (reg->state == DM_RH_DIRTY) {

			reg->state = DM_RH_CLEAN;