scsi: dm: Remove WRITE_SAME support

There are no more end-users of REQ_OP_WRITE_SAME left, so we can start
deleting it.

Link: https://lore.kernel.org/r/20220209082828.2629273-7-hch@lst.deReviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/md/dm-core.h

@@ -141,7 +141,6 @@ struct mapped_device {
 #define DMF_EMULATE_ZONE_APPEND 9
 
 void disable_discard(struct mapped_device *md);
-void disable_write_same(struct mapped_device *md);
 void disable_write_zeroes(struct mapped_device *md);
 
 static inline sector_t dm_get_size(struct mapped_device *md)

drivers/md/dm-crypt.c

@@ -2006,7 +2006,6 @@ static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
 	 */
 	switch (bio_op(ctx->bio_in)) {
 	case REQ_OP_WRITE:
-	case REQ_OP_WRITE_SAME:
 	case REQ_OP_WRITE_ZEROES:
 		return true;
 	default:

drivers/md/dm-ebs-target.c

@@ -335,7 +335,6 @@ static int ebs_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	ti->num_flush_bios = 1;
 	ti->num_discard_bios = 1;
 	ti->num_secure_erase_bios = 0;
-	ti->num_write_same_bios = 0;
 	ti->num_write_zeroes_bios = 0;
 	return 0;
 bad:

drivers/md/dm-io.c

@@ -304,7 +304,6 @@ static void do_region(int op, int op_flags, unsigned region,
 	unsigned num_bvecs;
 	sector_t remaining = where->count;
 	struct request_queue *q = bdev_get_queue(where->bdev);
-	unsigned short logical_block_size = queue_logical_block_size(q);
 	sector_t num_sectors;
 	unsigned int special_cmd_max_sectors;
 
@@ -315,10 +314,8 @@ static void do_region(int op, int op_flags, unsigned region,
 		special_cmd_max_sectors = q->limits.max_discard_sectors;
 	else if (op == REQ_OP_WRITE_ZEROES)
 		special_cmd_max_sectors = q->limits.max_write_zeroes_sectors;
-	else if (op == REQ_OP_WRITE_SAME)
-		special_cmd_max_sectors = q->limits.max_write_same_sectors;
-	if ((op == REQ_OP_DISCARD || op == REQ_OP_WRITE_ZEROES ||
-	     op == REQ_OP_WRITE_SAME) && special_cmd_max_sectors == 0) {
+	if ((op == REQ_OP_DISCARD || op == REQ_OP_WRITE_ZEROES) &&
+	    special_cmd_max_sectors == 0) {
 		atomic_inc(&io->count);
 		dec_count(io, region, BLK_STS_NOTSUPP);
 		return;
@@ -337,9 +334,6 @@ static void do_region(int op, int op_flags, unsigned region,
 		case REQ_OP_WRITE_ZEROES:
 			num_bvecs = 0;
 			break;
-		case REQ_OP_WRITE_SAME:
-			num_bvecs = 1;
-			break;
 		default:
 			num_bvecs = bio_max_segs(dm_sector_div_up(remaining,
 						(PAGE_SIZE >> SECTOR_SHIFT)));
@@ -356,18 +350,6 @@ static void do_region(int op, int op_flags, unsigned region,
 			num_sectors = min_t(sector_t, special_cmd_max_sectors, remaining);
 			bio->bi_iter.bi_size = num_sectors << SECTOR_SHIFT;
 			remaining -= num_sectors;
-		} else if (op == REQ_OP_WRITE_SAME) {
-			/*
-			 * WRITE SAME only uses a single page.
-			 */
-			dp->get_page(dp, &page, &len, &offset);
-			bio_add_page(bio, page, logical_block_size, offset);
-			num_sectors = min_t(sector_t, special_cmd_max_sectors, remaining);
-			bio->bi_iter.bi_size = num_sectors << SECTOR_SHIFT;
-
-			offset = 0;
-			remaining -= num_sectors;
-			dp->next_page(dp);
 		} else while (remaining) {
 			/*
 			 * Try and add as many pages as possible.

drivers/md/dm-linear.c

@@ -60,7 +60,6 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	ti->num_flush_bios = 1;
 	ti->num_discard_bios = 1;
 	ti->num_secure_erase_bios = 1;
-	ti->num_write_same_bios = 1;
 	ti->num_write_zeroes_bios = 1;
 	ti->private = lc;
 	return 0;

drivers/md/dm-mpath.c

@@ -1252,7 +1252,6 @@ static int multipath_ctr(struct dm_target *ti, unsigned argc, char **argv)
 
 	ti->num_flush_bios = 1;
 	ti->num_discard_bios = 1;
-	ti->num_write_same_bios = 1;
 	ti->num_write_zeroes_bios = 1;
 	if (m->queue_mode == DM_TYPE_BIO_BASED)
 		ti->per_io_data_size = multipath_per_bio_data_size();

drivers/md/dm-rq.c

@@ -217,9 +217,6 @@ static void dm_done(struct request *clone, blk_status_t error, bool mapped)
 		if (req_op(clone) == REQ_OP_DISCARD &&
 		    !clone->q->limits.max_discard_sectors)
 			disable_discard(tio->md);
-		else if (req_op(clone) == REQ_OP_WRITE_SAME &&
-			 !clone->q->limits.max_write_same_sectors)
-			disable_write_same(tio->md);
 		else if (req_op(clone) == REQ_OP_WRITE_ZEROES &&
 			 !clone->q->limits.max_write_zeroes_sectors)
 			disable_write_zeroes(tio->md);

drivers/md/dm-stripe.c

@@ -157,7 +157,6 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	ti->num_flush_bios = stripes;
 	ti->num_discard_bios = stripes;
 	ti->num_secure_erase_bios = stripes;
-	ti->num_write_same_bios = stripes;
 	ti->num_write_zeroes_bios = stripes;
 
 	sc->chunk_size = chunk_size;
@@ -284,8 +283,7 @@ static int stripe_map(struct dm_target *ti, struct bio *bio)
 	}
 	if (unlikely(bio_op(bio) == REQ_OP_DISCARD) ||
 	    unlikely(bio_op(bio) == REQ_OP_SECURE_ERASE) ||
-	    unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES) ||
-	    unlikely(bio_op(bio) == REQ_OP_WRITE_SAME)) {
+	    unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES)) {
 		target_bio_nr = dm_bio_get_target_bio_nr(bio);
 		BUG_ON(target_bio_nr >= sc->stripes);
 		return stripe_map_range(sc, bio, target_bio_nr);

drivers/md/dm-table.c

@@ -1822,33 +1822,6 @@ static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
 	return !blk_queue_add_random(q);
 }
 
-static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev,
-					 sector_t start, sector_t len, void *data)
-{
-	struct request_queue *q = bdev_get_queue(dev->bdev);
-
-	return !q->limits.max_write_same_sectors;
-}
-
-static bool dm_table_supports_write_same(struct dm_table *t)
-{
-	struct dm_target *ti;
-	unsigned i;
-
-	for (i = 0; i < dm_table_get_num_targets(t); i++) {
-		ti = dm_table_get_target(t, i);
-
-		if (!ti->num_write_same_bios)
-			return false;
-
-		if (!ti->type->iterate_devices ||
-		    ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
-			return false;
-	}
-
-	return true;
-}
-
 static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
 					   sector_t start, sector_t len, void *data)
 {
@@ -2027,8 +2000,6 @@ int dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
 	else
 		blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
 
-	if (!dm_table_supports_write_same(t))
-		q->limits.max_write_same_sectors = 0;
 	if (!dm_table_supports_write_zeroes(t))
 		q->limits.max_write_zeroes_sectors = 0;
 

drivers/md/dm-zone.c

@@ -130,7 +130,6 @@ bool dm_is_zone_write(struct mapped_device *md, struct bio *bio)
 
 	switch (bio_op(bio)) {
 	case REQ_OP_WRITE_ZEROES:
-	case REQ_OP_WRITE_SAME:
 	case REQ_OP_WRITE:
 		return !op_is_flush(bio->bi_opf) && bio_sectors(bio);
 	default:
@@ -390,7 +389,6 @@ static bool dm_zone_map_bio_begin(struct mapped_device *md,
 	case REQ_OP_ZONE_FINISH:
 		return true;
 	case REQ_OP_WRITE_ZEROES:
-	case REQ_OP_WRITE_SAME:
 	case REQ_OP_WRITE:
 		/* Writes must be aligned to the zone write pointer */
 		if ((clone->bi_iter.bi_sector & (zsectors - 1)) != zwp_offset)
@@ -446,7 +444,6 @@ static blk_status_t dm_zone_map_bio_end(struct mapped_device *md,
 			   blk_queue_zone_sectors(md->queue));
 		return BLK_STS_OK;
 	case REQ_OP_WRITE_ZEROES:
-	case REQ_OP_WRITE_SAME:
 	case REQ_OP_WRITE:
 		WRITE_ONCE(md->zwp_offset[zno], zwp_offset + nr_sectors);
 		return BLK_STS_OK;
@@ -503,7 +500,6 @@ static bool dm_need_zone_wp_tracking(struct bio *orig_bio)
 		return false;
 	switch (bio_op(orig_bio)) {
 	case REQ_OP_WRITE_ZEROES:
-	case REQ_OP_WRITE_SAME:
 	case REQ_OP_WRITE:
 	case REQ_OP_ZONE_RESET:
 	case REQ_OP_ZONE_FINISH:

drivers/md/dm.c

@@ -855,14 +855,6 @@ void disable_discard(struct mapped_device *md)
 	blk_queue_flag_clear(QUEUE_FLAG_DISCARD, md->queue);
 }
 
-void disable_write_same(struct mapped_device *md)
-{
-	struct queue_limits *limits = dm_get_queue_limits(md);
-
-	/* device doesn't really support WRITE SAME, disable it */
-	limits->max_write_same_sectors = 0;
-}
-
 void disable_write_zeroes(struct mapped_device *md)
 {
 	struct queue_limits *limits = dm_get_queue_limits(md);
@@ -889,9 +881,6 @@ static void clone_endio(struct bio *bio)
 		if (bio_op(bio) == REQ_OP_DISCARD &&
 		    !q->limits.max_discard_sectors)
 			disable_discard(md);
-		else if (bio_op(bio) == REQ_OP_WRITE_SAME &&
-			 !q->limits.max_write_same_sectors)
-			disable_write_same(md);
 		else if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
 			 !q->limits.max_write_zeroes_sectors)
 			disable_write_zeroes(md);
@@ -1370,7 +1359,6 @@ static bool is_abnormal_io(struct bio *bio)
 	switch (bio_op(bio)) {
 	case REQ_OP_DISCARD:
 	case REQ_OP_SECURE_ERASE:
-	case REQ_OP_WRITE_SAME:
 	case REQ_OP_WRITE_ZEROES:
 		r = true;
 		break;
@@ -1392,9 +1380,6 @@ static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti,
 	case REQ_OP_SECURE_ERASE:
 		num_bios = ti->num_secure_erase_bios;
 		break;
-	case REQ_OP_WRITE_SAME:
-		num_bios = ti->num_write_same_bios;
-		break;
 	case REQ_OP_WRITE_ZEROES:
 		num_bios = ti->num_write_zeroes_bios;
 		break;

include/linux/device-mapper.h

@@ -316,12 +316,6 @@ struct dm_target {
 	 */
 	unsigned num_secure_erase_bios;
 
-	/*
-	 * The number of WRITE SAME bios that will be submitted to the target.
-	 * The bio number can be accessed with dm_bio_get_target_bio_nr.
-	 */
-	unsigned num_write_same_bios;
-
 	/*
 	 * The number of WRITE ZEROES bios that will be submitted to the target.
 	 * The bio number can be accessed with dm_bio_get_target_bio_nr.