From: Hannes Reinecke <hare@suse.de>
Date: Mon, 11 May 2020 10:24:20 +0200
Subject: [PATCH] dm zoned: store device in struct dmz_sb
Git-commit: bf28a3ba098676831bde49e8bc47849727d532a5
Patch-mainline: v5.8-rc1
References: bsc#1175995,jsc#SLE-15608

Store the device together with the superblock so that
we don't have to recur to the metadata to find it.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/md/dm-zoned-metadata.c | 90 +++++++++++++++++++++++++++---------------
 1 file changed, 59 insertions(+), 31 deletions(-)

diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c
index 900b1c1224f5..def836e12dd9 100644
--- a/drivers/md/dm-zoned-metadata.c
+++ b/drivers/md/dm-zoned-metadata.c
@@ -122,6 +122,7 @@ enum {
  */
 struct dmz_sb {
 	sector_t		block;
+	struct dmz_dev		*dev;
 	struct dmz_mblock	*mblk;
 	struct dmz_super	*sb;
 	struct dm_zone		*zone;
@@ -197,6 +198,11 @@ sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone)
 	return (sector_t)zone->id << zmd->dev->zone_nr_blocks_shift;
 }
 
+struct dmz_dev *dmz_zone_to_dev(struct dmz_metadata *zmd, struct dm_zone *zone)
+{
+	return &zmd->dev[0];
+}
+
 unsigned int dmz_nr_zones(struct dmz_metadata *zmd)
 {
 	return zmd->dev->nr_zones;
@@ -412,9 +418,10 @@ static struct dmz_mblock *dmz_get_mblock_slow(struct dmz_metadata *zmd,
 {
 	struct dmz_mblock *mblk, *m;
 	sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no;
+	struct dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev;
 	struct bio *bio;
 
-	if (dmz_bdev_is_dying(zmd->dev))
+	if (dmz_bdev_is_dying(dev))
 		return ERR_PTR(-EIO);
 
 	/* Get a new block and a BIO to read it */
@@ -450,7 +457,7 @@ static struct dmz_mblock *dmz_get_mblock_slow(struct dmz_metadata *zmd,
 
 	/* Submit read BIO */
 	bio->bi_iter.bi_sector = dmz_blk2sect(block);
-	bio_set_dev(bio, zmd->dev->bdev);
+	bio_set_dev(bio, dev->bdev);
 	bio->bi_private = mblk;
 	bio->bi_end_io = dmz_mblock_bio_end_io;
 	bio_set_op_attrs(bio, REQ_OP_READ, REQ_META | REQ_PRIO);
@@ -547,6 +554,7 @@ static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd,
 					 sector_t mblk_no)
 {
 	struct dmz_mblock *mblk;
+	struct dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev;
 
 	/* Check rbtree */
 	spin_lock(&zmd->mblk_lock);
@@ -565,7 +573,7 @@ static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd,
 		       TASK_UNINTERRUPTIBLE);
 	if (test_bit(DMZ_META_ERROR, &mblk->state)) {
 		dmz_release_mblock(zmd, mblk);
-		dmz_check_bdev(zmd->dev);
+		dmz_check_bdev(dev);
 		return ERR_PTR(-EIO);
 	}
 
@@ -589,10 +597,11 @@ static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
 static int dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
 			    unsigned int set)
 {
+	struct dmz_dev *dev = zmd->sb[set].dev;
 	sector_t block = zmd->sb[set].block + mblk->no;
 	struct bio *bio;
 
-	if (dmz_bdev_is_dying(zmd->dev))
+	if (dmz_bdev_is_dying(dev))
 		return -EIO;
 
 	bio = bio_alloc(GFP_NOIO, 1);
@@ -604,7 +613,7 @@ static int dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
 	set_bit(DMZ_META_WRITING, &mblk->state);
 
 	bio->bi_iter.bi_sector = dmz_blk2sect(block);
-	bio_set_dev(bio, zmd->dev->bdev);
+	bio_set_dev(bio, dev->bdev);
 	bio->bi_private = mblk;
 	bio->bi_end_io = dmz_mblock_bio_end_io;
 	bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO);
@@ -617,13 +626,13 @@ static int dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
 /*
  * Read/write a metadata block.
  */
-static int dmz_rdwr_block(struct dmz_metadata *zmd, int op, sector_t block,
-			  struct page *page)
+static int dmz_rdwr_block(struct dmz_dev *dev, int op,
+			  sector_t block, struct page *page)
 {
 	struct bio *bio;
 	int ret;
 
-	if (dmz_bdev_is_dying(zmd->dev))
+	if (dmz_bdev_is_dying(dev))
 		return -EIO;
 
 	bio = bio_alloc(GFP_NOIO, 1);
@@ -631,14 +640,14 @@ static int dmz_rdwr_block(struct dmz_metadata *zmd, int op, sector_t block,
 		return -ENOMEM;
 
 	bio->bi_iter.bi_sector = dmz_blk2sect(block);
-	bio_set_dev(bio, zmd->dev->bdev);
+	bio_set_dev(bio, dev->bdev);
 	bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO);
 	bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0);
 	ret = submit_bio_wait(bio);
 	bio_put(bio);
 
 	if (ret)
-		dmz_check_bdev(zmd->dev);
+		dmz_check_bdev(dev);
 	return ret;
 }
 
@@ -650,6 +659,7 @@ static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set)
 	sector_t block = zmd->sb[set].block;
 	struct dmz_mblock *mblk = zmd->sb[set].mblk;
 	struct dmz_super *sb = zmd->sb[set].sb;
+	struct dmz_dev *dev = zmd->sb[set].dev;
 	u64 sb_gen = zmd->sb_gen + 1;
 	int ret;
 
@@ -669,9 +679,9 @@ static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set)
 	sb->crc = 0;
 	sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE));
 
-	ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page);
+	ret = dmz_rdwr_block(dev, REQ_OP_WRITE, block, mblk->page);
 	if (ret == 0)
-		ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO);
+		ret = blkdev_issue_flush(dev->bdev, GFP_NOIO);
 
 	return ret;
 }
@@ -684,6 +694,7 @@ static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
 				   unsigned int set)
 {
 	struct dmz_mblock *mblk;
+	struct dmz_dev *dev = zmd->sb[set].dev;
 	struct blk_plug plug;
 	int ret = 0, nr_mblks_submitted = 0;
 
@@ -705,7 +716,7 @@ static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
 			       TASK_UNINTERRUPTIBLE);
 		if (test_bit(DMZ_META_ERROR, &mblk->state)) {
 			clear_bit(DMZ_META_ERROR, &mblk->state);
-			dmz_check_bdev(zmd->dev);
+			dmz_check_bdev(dev);
 			ret = -EIO;
 		}
 		nr_mblks_submitted--;
@@ -713,7 +724,7 @@ static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
 
 	/* Flush drive cache (this will also sync data) */
 	if (ret == 0)
-		ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO);
+		ret = blkdev_issue_flush(dev->bdev, GFP_NOIO);
 
 	return ret;
 }
@@ -750,6 +761,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd)
 {
 	struct dmz_mblock *mblk;
 	struct list_head write_list;
+	struct dmz_dev *dev;
 	int ret;
 
 	if (WARN_ON(!zmd))
@@ -763,6 +775,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd)
 	 * from modifying metadata.
 	 */
 	down_write(&zmd->mblk_sem);
+	dev = zmd->sb[zmd->mblk_primary].dev;
 
 	/*
 	 * This is called from the target flush work and reclaim work.
@@ -770,7 +783,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd)
 	 */
 	dmz_lock_flush(zmd);
 
-	if (dmz_bdev_is_dying(zmd->dev)) {
+	if (dmz_bdev_is_dying(dev)) {
 		ret = -EIO;
 		goto out;
 	}
@@ -782,7 +795,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd)
 
 	/* If there are no dirty metadata blocks, just flush the device cache */
 	if (list_empty(&write_list)) {
-		ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO);
+		ret = blkdev_issue_flush(dev->bdev, GFP_NOIO);
 		goto err;
 	}
 
@@ -831,7 +844,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd)
 		list_splice(&write_list, &zmd->mblk_dirty_list);
 		spin_unlock(&zmd->mblk_lock);
 	}
-	if (!dmz_check_bdev(zmd->dev))
+	if (!dmz_check_bdev(dev))
 		ret = -EIO;
 	goto out;
 }
@@ -842,8 +855,8 @@ int dmz_flush_metadata(struct dmz_metadata *zmd)
 static int dmz_check_sb(struct dmz_metadata *zmd, unsigned int set)
 {
 	struct dmz_super *sb = zmd->sb[set].sb;
+	struct dmz_dev *dev = zmd->sb[set].dev;
 	unsigned int nr_meta_zones, nr_data_zones;
-	struct dmz_dev *dev = zmd->dev;
 	u32 crc, stored_crc;
 	u64 gen;
 
@@ -908,8 +921,8 @@ static int dmz_check_sb(struct dmz_metadata *zmd, unsigned int set)
  */
 static int dmz_read_sb(struct dmz_metadata *zmd, unsigned int set)
 {
-	return dmz_rdwr_block(zmd, REQ_OP_READ, zmd->sb[set].block,
-			      zmd->sb[set].mblk->page);
+	return dmz_rdwr_block(zmd->sb[set].dev, REQ_OP_READ,
+			      zmd->sb[set].block, zmd->sb[set].mblk->page);
 }
 
 /*
@@ -934,6 +947,7 @@ static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
 	/* Bad first super block: search for the second one */
 	zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks;
 	zmd->sb[1].zone = zmd->sb[0].zone + 1;
+	zmd->sb[1].dev = dmz_zone_to_dev(zmd, zmd->sb[1].zone);
 	for (i = 0; i < zmd->nr_rnd_zones - 1; i++) {
 		if (dmz_read_sb(zmd, 1) != 0)
 			break;
@@ -942,11 +956,13 @@ static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
 			return 0;
 		}
 		zmd->sb[1].block += zone_nr_blocks;
+		zmd->sb[1].dev = dmz_zone_to_dev(zmd, zmd->sb[1].zone + i);
 	}
 
 	dmz_free_mblock(zmd, mblk);
 	zmd->sb[1].mblk = NULL;
 	zmd->sb[1].zone = NULL;
+	zmd->sb[1].dev = NULL;
 
 	return -EIO;
 }
@@ -987,7 +1003,8 @@ static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set)
 	struct page *page;
 	int i, ret;
 
-	dmz_dev_warn(zmd->dev, "Metadata set %u invalid: recovering", dst_set);
+	dmz_dev_warn(zmd->sb[dst_set].dev,
+		     "Metadata set %u invalid: recovering", dst_set);
 
 	if (dst_set == 0)
 		zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone);
@@ -1000,11 +1017,11 @@ static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set)
 
 	/* Copy metadata blocks */
 	for (i = 1; i < zmd->nr_meta_blocks; i++) {
-		ret = dmz_rdwr_block(zmd, REQ_OP_READ,
+		ret = dmz_rdwr_block(zmd->sb[src_set].dev, REQ_OP_READ,
 				     zmd->sb[src_set].block + i, page);
 		if (ret)
 			goto out;
-		ret = dmz_rdwr_block(zmd, REQ_OP_WRITE,
+		ret = dmz_rdwr_block(zmd->sb[dst_set].dev, REQ_OP_WRITE,
 				     zmd->sb[dst_set].block + i, page);
 		if (ret)
 			goto out;
@@ -1043,9 +1060,10 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
 
 	/* Read and check the primary super block */
 	zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone);
+	zmd->sb[0].dev = dmz_zone_to_dev(zmd, zmd->sb[0].zone);
 	ret = dmz_get_sb(zmd, 0);
 	if (ret) {
-		dmz_dev_err(zmd->dev, "Read primary super block failed");
+		dmz_dev_err(zmd->sb[0].dev, "Read primary super block failed");
 		return ret;
 	}
 
@@ -1057,12 +1075,13 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
 		if (!zmd->sb[1].zone)
 			zmd->sb[1].zone = zmd->sb[0].zone + zmd->nr_meta_zones;
 		zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone);
+		zmd->sb[1].dev = dmz_zone_to_dev(zmd, zmd->sb[1].zone);
 		ret = dmz_get_sb(zmd, 1);
 	} else
 		ret = dmz_lookup_secondary_sb(zmd);
 
 	if (ret) {
-		dmz_dev_err(zmd->dev, "Read secondary super block failed");
+		dmz_dev_err(zmd->sb[1].dev, "Read secondary super block failed");
 		return ret;
 	}
 
@@ -1078,17 +1097,25 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
 
 	if (sb_good[0])
 		sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen);
-	else
+	else {
 		ret = dmz_recover_mblocks(zmd, 0);
+		if (ret) {
+			dmz_dev_err(zmd->sb[0].dev,
+				    "Recovery of superblock 0 failed");
+			return -EIO;
+		}
+	}
 
 	if (sb_good[1])
 		sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen);
-	else
+	else {
 		ret = dmz_recover_mblocks(zmd, 1);
 
-	if (ret) {
-		dmz_dev_err(zmd->dev, "Recovery failed");
-		return -EIO;
+		if (ret) {
+			dmz_dev_err(zmd->sb[1].dev,
+				    "Recovery of superblock 1 failed");
+			return -EIO;
+		}
 	}
 
 	if (sb_gen[0] >= sb_gen[1]) {
@@ -1099,7 +1126,8 @@ static int dmz_load_sb(struct dmz_metadata *zmd)
 		zmd->mblk_primary = 1;
 	}
 
-	dmz_dev_debug(zmd->dev, "Using super block %u (gen %llu)",
+	dmz_dev_debug(zmd->sb[zmd->mblk_primary].dev,
+		      "Using super block %u (gen %llu)",
 		      zmd->mblk_primary, zmd->sb_gen);
 
 	return 0;
-- 
2.16.4

