1 files changed, 129 insertions, 39 deletions

diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index ce7a6a56cf73..d6c0bc76e837 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -29,7 +29,8 @@
 #define UNSUPPORTED_MDDEV_FLAGS		\
 	((1L << MD_HAS_JOURNAL) |	\
 	 (1L << MD_JOURNAL_CLEAN) |	\
-	 (1L << MD_FAILFAST_SUPPORTED))
+	 (1L << MD_FAILFAST_SUPPORTED) |\
+	 (1L << MD_HAS_PPL))
 
 static int raid0_congested(struct mddev *mddev, int bits)
 {
@@ -384,7 +385,7 @@ static int raid0_run(struct mddev *mddev)
 		blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors);
 		blk_queue_max_write_same_sectors(mddev->queue, mddev->chunk_sectors);
 		blk_queue_max_write_zeroes_sectors(mddev->queue, mddev->chunk_sectors);
-		blk_queue_max_discard_sectors(mddev->queue, mddev->chunk_sectors);
+		blk_queue_max_discard_sectors(mddev->queue, UINT_MAX);
 
 		blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9);
 		blk_queue_io_opt(mddev->queue,
@@ -458,57 +459,146 @@ static inline int is_io_in_chunk_boundary(struct mddev *mddev,
 	}
 }
 
+static void raid0_handle_discard(struct mddev *mddev, struct bio *bio)
+{
+	struct r0conf *conf = mddev->private;
+	struct strip_zone *zone;
+	sector_t start = bio->bi_iter.bi_sector;
+	sector_t end;
+	unsigned int stripe_size;
+	sector_t first_stripe_index, last_stripe_index;
+	sector_t start_disk_offset;
+	unsigned int start_disk_index;
+	sector_t end_disk_offset;
+	unsigned int end_disk_index;
+	unsigned int disk;
+
+	zone = find_zone(conf, &start);
+
+	if (bio_end_sector(bio) > zone->zone_end) {
+		struct bio *split = bio_split(bio,
+			zone->zone_end - bio->bi_iter.bi_sector, GFP_NOIO,
+			mddev->bio_set);
+		bio_chain(split, bio);
+		generic_make_request(bio);
+		bio = split;
+		end = zone->zone_end;
+	} else
+		end = bio_end_sector(bio);
+
+	if (zone != conf->strip_zone)
+		end = end - zone[-1].zone_end;
+
+	/* Now start and end is the offset in zone */
+	stripe_size = zone->nb_dev * mddev->chunk_sectors;
+
+	first_stripe_index = start;
+	sector_div(first_stripe_index, stripe_size);
+	last_stripe_index = end;
+	sector_div(last_stripe_index, stripe_size);
+
+	start_disk_index = (int)(start - first_stripe_index * stripe_size) /
+		mddev->chunk_sectors;
+	start_disk_offset = ((int)(start - first_stripe_index * stripe_size) %
+		mddev->chunk_sectors) +
+		first_stripe_index * mddev->chunk_sectors;
+	end_disk_index = (int)(end - last_stripe_index * stripe_size) /
+		mddev->chunk_sectors;
+	end_disk_offset = ((int)(end - last_stripe_index * stripe_size) %
+		mddev->chunk_sectors) +
+		last_stripe_index * mddev->chunk_sectors;
+
+	for (disk = 0; disk < zone->nb_dev; disk++) {
+		sector_t dev_start, dev_end;
+		struct bio *discard_bio = NULL;
+		struct md_rdev *rdev;
+
+		if (disk < start_disk_index)
+			dev_start = (first_stripe_index + 1) *
+				mddev->chunk_sectors;
+		else if (disk > start_disk_index)
+			dev_start = first_stripe_index * mddev->chunk_sectors;
+		else
+			dev_start = start_disk_offset;
+
+		if (disk < end_disk_index)
+			dev_end = (last_stripe_index + 1) * mddev->chunk_sectors;
+		else if (disk > end_disk_index)
+			dev_end = last_stripe_index * mddev->chunk_sectors;
+		else
+			dev_end = end_disk_offset;
+
+		if (dev_end <= dev_start)
+			continue;
+
+		rdev = conf->devlist[(zone - conf->strip_zone) *
+			conf->strip_zone[0].nb_dev + disk];
+		if (__blkdev_issue_discard(rdev->bdev,
+			dev_start + zone->dev_start + rdev->data_offset,
+			dev_end - dev_start, GFP_NOIO, 0, &discard_bio) ||
+		    !discard_bio)
+			continue;
+		bio_chain(discard_bio, bio);
+		if (mddev->gendisk)
+			trace_block_bio_remap(bdev_get_queue(rdev->bdev),
+				discard_bio, disk_devt(mddev->gendisk),
+				bio->bi_iter.bi_sector);
+		generic_make_request(discard_bio);
+	}
+	bio_endio(bio);
+}
+
 static void raid0_make_request(struct mddev *mddev, struct bio *bio)
 {
 	struct strip_zone *zone;
 	struct md_rdev *tmp_dev;
-	struct bio *split;
+	sector_t bio_sector;
+	sector_t sector;
+	unsigned chunk_sects;
+	unsigned sectors;
 
 	if (unlikely(bio->bi_opf & REQ_PREFLUSH)) {
 		md_flush_request(mddev, bio);
 		return;
 	}
 
-	do {
-		sector_t bio_sector = bio->bi_iter.bi_sector;
-		sector_t sector = bio_sector;
-		unsigned chunk_sects = mddev->chunk_sectors;
+	if (unlikely((bio_op(bio) == REQ_OP_DISCARD))) {
+		raid0_handle_discard(mddev, bio);
+		return;
+	}
+
+	bio_sector = bio->bi_iter.bi_sector;
+	sector = bio_sector;
+	chunk_sects = mddev->chunk_sectors;
 
-		unsigned sectors = chunk_sects -
-			(likely(is_power_of_2(chunk_sects))
-			 ? (sector & (chunk_sects-1))
-			 : sector_div(sector, chunk_sects));
+	sectors = chunk_sects -
+		(likely(is_power_of_2(chunk_sects))
+		 ? (sector & (chunk_sects-1))
+		 : sector_div(sector, chunk_sects));
 
-		/* Restore due to sector_div */
-		sector = bio_sector;
+	/* Restore due to sector_div */
+	sector = bio_sector;
 
-		if (sectors < bio_sectors(bio)) {
-			split = bio_split(bio, sectors, GFP_NOIO, fs_bio_set);
-			bio_chain(split, bio);
-		} else {
-			split = bio;
-		}
+	if (sectors < bio_sectors(bio)) {
+		struct bio *split = bio_split(bio, sectors, GFP_NOIO, mddev->bio_set);
+		bio_chain(split, bio);
+		generic_make_request(bio);
+		bio = split;
+	}
 
-		zone = find_zone(mddev->private, &sector);
-		tmp_dev = map_sector(mddev, zone, sector, &sector);
-		split->bi_bdev = tmp_dev->bdev;
-		split->bi_iter.bi_sector = sector + zone->dev_start +
-			tmp_dev->data_offset;
-
-		if (unlikely((bio_op(split) == REQ_OP_DISCARD) &&
-			 !blk_queue_discard(bdev_get_queue(split->bi_bdev)))) {
-			/* Just ignore it */
-			bio_endio(split);
-		} else {
-			if (mddev->gendisk)
-				trace_block_bio_remap(bdev_get_queue(split->bi_bdev),
-						      split, disk_devt(mddev->gendisk),
-						      bio_sector);
-			mddev_check_writesame(mddev, split);
-			mddev_check_write_zeroes(mddev, split);
-			generic_make_request(split);
-		}
-	} while (split != bio);
+	zone = find_zone(mddev->private, &sector);
+	tmp_dev = map_sector(mddev, zone, sector, &sector);
+	bio->bi_bdev = tmp_dev->bdev;
+	bio->bi_iter.bi_sector = sector + zone->dev_start +
+		tmp_dev->data_offset;
+
+	if (mddev->gendisk)
+		trace_block_bio_remap(bdev_get_queue(bio->bi_bdev),
+				      bio, disk_devt(mddev->gendisk),
+				      bio_sector);
+	mddev_check_writesame(mddev, bio);
+	mddev_check_write_zeroes(mddev, bio);
+	generic_make_request(bio);
 }
 
 static void raid0_status(struct seq_file *seq, struct mddev *mddev)