1 files changed, 202 insertions, 88 deletions

diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
index 21df48e6c4fa..fa1d321a2fb8 100644
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -41,13 +41,17 @@ static bool bbio_has_ordered_extent(const struct btrfs_bio *bbio)
  * Initialize a btrfs_bio structure.  This skips the embedded bio itself as it
  * is already initialized by the block layer.
  */
-void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info,
+void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_inode *inode, u64 file_offset,
 		    btrfs_bio_end_io_t end_io, void *private)
 {
+	/* @inode parameter is mandatory. */
+	ASSERT(inode);
+
 	memset(bbio, 0, offsetof(struct btrfs_bio, bio));
-	bbio->fs_info = fs_info;
+	bbio->inode = inode;
 	bbio->end_io = end_io;
 	bbio->private = private;
+	bbio->file_offset = file_offset;
 	atomic_set(&bbio->pending_ios, 1);
 	WRITE_ONCE(bbio->status, BLK_STS_OK);
 }
@@ -60,7 +64,7 @@ void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info,
  * a mempool.
  */
 struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
-				  struct btrfs_fs_info *fs_info,
+				  struct btrfs_inode *inode, u64 file_offset,
 				  btrfs_bio_end_io_t end_io, void *private)
 {
 	struct btrfs_bio *bbio;
@@ -68,7 +72,7 @@ struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
 
 	bio = bio_alloc_bioset(NULL, nr_vecs, opf, GFP_NOFS, &btrfs_bioset);
 	bbio = btrfs_bio(bio);
-	btrfs_bio_init(bbio, fs_info, end_io, private);
+	btrfs_bio_init(bbio, inode, file_offset, end_io, private);
 	return bbio;
 }
 
@@ -85,13 +89,13 @@ static struct btrfs_bio *btrfs_split_bio(struct btrfs_fs_info *fs_info,
 		return ERR_CAST(bio);
 
 	bbio = btrfs_bio(bio);
-	btrfs_bio_init(bbio, fs_info, NULL, orig_bbio);
-	bbio->inode = orig_bbio->inode;
-	bbio->file_offset = orig_bbio->file_offset;
+	btrfs_bio_init(bbio, orig_bbio->inode, orig_bbio->file_offset, NULL, orig_bbio);
 	orig_bbio->file_offset += map_length;
 	if (bbio_has_ordered_extent(bbio)) {
 		refcount_inc(&orig_bbio->ordered->refs);
 		bbio->ordered = orig_bbio->ordered;
+		bbio->orig_logical = orig_bbio->orig_logical;
+		orig_bbio->orig_logical += map_length;
 	}
 	bbio->csum_search_commit_root = orig_bbio->csum_search_commit_root;
 	atomic_inc(&orig_bbio->pending_ios);
@@ -100,6 +104,12 @@ static struct btrfs_bio *btrfs_split_bio(struct btrfs_fs_info *fs_info,
 
 void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status)
 {
+	/* Make sure we're already in task context. */
+	ASSERT(in_task());
+
+	if (bbio->async_csum)
+		wait_for_completion(&bbio->csum_done);
+
 	bbio->bio.bi_status = status;
 	if (bbio->bio.bi_pool == &btrfs_clone_bioset) {
 		struct btrfs_bio *orig_bbio = bbio->private;
@@ -163,11 +173,30 @@ static void btrfs_end_repair_bio(struct btrfs_bio *repair_bbio,
 	struct btrfs_failed_bio *fbio = repair_bbio->private;
 	struct btrfs_inode *inode = repair_bbio->inode;
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
-	struct bio_vec *bv = bio_first_bvec_all(&repair_bbio->bio);
+	/*
+	 * We can not move forward the saved_iter, as it will be later
+	 * utilized by repair_bbio again.
+	 */
+	struct bvec_iter saved_iter = repair_bbio->saved_iter;
+	const u32 step = min(fs_info->sectorsize, PAGE_SIZE);
+	const u64 logical = repair_bbio->saved_iter.bi_sector << SECTOR_SHIFT;
+	const u32 nr_steps = repair_bbio->saved_iter.bi_size / step;
 	int mirror = repair_bbio->mirror_num;
+	phys_addr_t paddrs[BTRFS_MAX_BLOCKSIZE / PAGE_SIZE];
+	phys_addr_t paddr;
+	unsigned int slot = 0;
+
+	/* Repair bbio should be eaxctly one block sized. */
+	ASSERT(repair_bbio->saved_iter.bi_size == fs_info->sectorsize);
+
+	btrfs_bio_for_each_block(paddr, &repair_bbio->bio, &saved_iter, step) {
+		ASSERT(slot < nr_steps);
+		paddrs[slot] = paddr;
+		slot++;
+	}
 
 	if (repair_bbio->bio.bi_status ||
-	    !btrfs_data_csum_ok(repair_bbio, dev, 0, bvec_phys(bv))) {
+	    !btrfs_data_csum_ok(repair_bbio, dev, 0, paddrs)) {
 		bio_reset(&repair_bbio->bio, NULL, REQ_OP_READ);
 		repair_bbio->bio.bi_iter = repair_bbio->saved_iter;
 
@@ -186,8 +215,7 @@ static void btrfs_end_repair_bio(struct btrfs_bio *repair_bbio,
 		mirror = prev_repair_mirror(fbio, mirror);
 		btrfs_repair_io_failure(fs_info, btrfs_ino(inode),
 				  repair_bbio->file_offset, fs_info->sectorsize,
-				  repair_bbio->saved_iter.bi_sector << SECTOR_SHIFT,
-				  bvec_phys(bv), mirror);
+				  logical, paddrs, step, mirror);
 	} while (mirror != fbio->bbio->mirror_num);
 
 done:
@@ -204,21 +232,25 @@ done:
  */
 static struct btrfs_failed_bio *repair_one_sector(struct btrfs_bio *failed_bbio,
 						  u32 bio_offset,
-						  phys_addr_t paddr,
+						  phys_addr_t paddrs[],
 						  struct btrfs_failed_bio *fbio)
 {
 	struct btrfs_inode *inode = failed_bbio->inode;
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
-	struct folio *folio = page_folio(phys_to_page(paddr));
 	const u32 sectorsize = fs_info->sectorsize;
-	const u32 foff = offset_in_folio(folio, paddr);
-	const u64 logical = (failed_bbio->saved_iter.bi_sector << SECTOR_SHIFT);
+	const u32 step = min(fs_info->sectorsize, PAGE_SIZE);
+	const u32 nr_steps = sectorsize / step;
+	/*
+	 * For bs > ps cases, the saved_iter can be partially moved forward.
+	 * In that case we should round it down to the block boundary.
+	 */
+	const u64 logical = round_down(failed_bbio->saved_iter.bi_sector << SECTOR_SHIFT,
+				       sectorsize);
 	struct btrfs_bio *repair_bbio;
 	struct bio *repair_bio;
 	int num_copies;
 	int mirror;
 
-	ASSERT(foff + sectorsize <= folio_size(folio));
 	btrfs_debug(fs_info, "repair read error: read error at %llu",
 		    failed_bbio->file_offset + bio_offset);
 
@@ -238,15 +270,22 @@ static struct btrfs_failed_bio *repair_one_sector(struct btrfs_bio *failed_bbio,
 
 	atomic_inc(&fbio->repair_count);
 
-	repair_bio = bio_alloc_bioset(NULL, 1, REQ_OP_READ, GFP_NOFS,
+	repair_bio = bio_alloc_bioset(NULL, nr_steps, REQ_OP_READ, GFP_NOFS,
 				      &btrfs_repair_bioset);
-	repair_bio->bi_iter.bi_sector = failed_bbio->saved_iter.bi_sector;
-	bio_add_folio_nofail(repair_bio, folio, sectorsize, foff);
+	repair_bio->bi_iter.bi_sector = logical >> SECTOR_SHIFT;
+	for (int i = 0; i < nr_steps; i++) {
+		int ret;
+
+		ASSERT(offset_in_page(paddrs[i]) + step <= PAGE_SIZE);
+
+		ret = bio_add_page(repair_bio, phys_to_page(paddrs[i]), step,
+				   offset_in_page(paddrs[i]));
+		ASSERT(ret == step);
+	}
 
 	repair_bbio = btrfs_bio(repair_bio);
-	btrfs_bio_init(repair_bbio, fs_info, NULL, fbio);
-	repair_bbio->inode = failed_bbio->inode;
-	repair_bbio->file_offset = failed_bbio->file_offset + bio_offset;
+	btrfs_bio_init(repair_bbio, failed_bbio->inode, failed_bbio->file_offset + bio_offset,
+		       NULL, fbio);
 
 	mirror = next_repair_mirror(fbio, failed_bbio->mirror_num);
 	btrfs_debug(fs_info, "submitting repair read to mirror %d", mirror);
@@ -258,10 +297,13 @@ static void btrfs_check_read_bio(struct btrfs_bio *bbio, struct btrfs_device *de
 {
 	struct btrfs_inode *inode = bbio->inode;
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
-	u32 sectorsize = fs_info->sectorsize;
+	const u32 sectorsize = fs_info->sectorsize;
+	const u32 step = min(sectorsize, PAGE_SIZE);
+	const u32 nr_steps = sectorsize / step;
 	struct bvec_iter *iter = &bbio->saved_iter;
 	blk_status_t status = bbio->bio.bi_status;
 	struct btrfs_failed_bio *fbio = NULL;
+	phys_addr_t paddrs[BTRFS_MAX_BLOCKSIZE / PAGE_SIZE];
 	phys_addr_t paddr;
 	u32 offset = 0;
 
@@ -280,13 +322,19 @@ static void btrfs_check_read_bio(struct btrfs_bio *bbio, struct btrfs_device *de
 	/* Clear the I/O error. A failed repair will reset it. */
 	bbio->bio.bi_status = BLK_STS_OK;
 
-	btrfs_bio_for_each_block(paddr, &bbio->bio, iter, fs_info->sectorsize) {
-		if (status || !btrfs_data_csum_ok(bbio, dev, offset, paddr))
-			fbio = repair_one_sector(bbio, offset, paddr, fbio);
-		offset += sectorsize;
+	btrfs_bio_for_each_block(paddr, &bbio->bio, iter, step) {
+		paddrs[(offset / step) % nr_steps] = paddr;
+		offset += step;
+
+		if (IS_ALIGNED(offset, sectorsize)) {
+			if (status ||
+			    !btrfs_data_csum_ok(bbio, dev, offset - sectorsize, paddrs))
+				fbio = repair_one_sector(bbio, offset - sectorsize,
+							 paddrs, fbio);
+		}
 	}
 	if (bbio->csum != bbio->csum_inline)
-		kfree(bbio->csum);
+		kvfree(bbio->csum);
 
 	if (fbio)
 		btrfs_repair_done(fbio);
@@ -317,36 +365,35 @@ static struct workqueue_struct *btrfs_end_io_wq(const struct btrfs_fs_info *fs_i
 	return fs_info->endio_workers;
 }
 
-static void btrfs_end_bio_work(struct work_struct *work)
+static void simple_end_io_work(struct work_struct *work)
 {
 	struct btrfs_bio *bbio = container_of(work, struct btrfs_bio, end_io_work);
+	struct bio *bio = &bbio->bio;
 
-	/* Metadata reads are checked and repaired by the submitter. */
-	if (is_data_bbio(bbio))
-		btrfs_check_read_bio(bbio, bbio->bio.bi_private);
-	else
-		btrfs_bio_end_io(bbio, bbio->bio.bi_status);
+	if (bio_op(bio) == REQ_OP_READ) {
+		/* Metadata reads are checked and repaired by the submitter. */
+		if (is_data_bbio(bbio))
+			return btrfs_check_read_bio(bbio, bbio->bio.bi_private);
+		return btrfs_bio_end_io(bbio, bbio->bio.bi_status);
+	}
+	if (bio_is_zone_append(bio) && !bio->bi_status)
+		btrfs_record_physical_zoned(bbio);
+	btrfs_bio_end_io(bbio, bbio->bio.bi_status);
 }
 
 static void btrfs_simple_end_io(struct bio *bio)
 {
 	struct btrfs_bio *bbio = btrfs_bio(bio);
 	struct btrfs_device *dev = bio->bi_private;
-	struct btrfs_fs_info *fs_info = bbio->fs_info;
+	struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
 
 	btrfs_bio_counter_dec(fs_info);
 
 	if (bio->bi_status)
 		btrfs_log_dev_io_error(bio, dev);
 
-	if (bio_op(bio) == REQ_OP_READ) {
-		INIT_WORK(&bbio->end_io_work, btrfs_end_bio_work);
-		queue_work(btrfs_end_io_wq(fs_info, bio), &bbio->end_io_work);
-	} else {
-		if (bio_is_zone_append(bio) && !bio->bi_status)
-			btrfs_record_physical_zoned(bbio);
-		btrfs_bio_end_io(bbio, bbio->bio.bi_status);
-	}
+	INIT_WORK(&bbio->end_io_work, simple_end_io_work);
+	queue_work(btrfs_end_io_wq(fs_info, bio), &bbio->end_io_work);
 }
 
 static void btrfs_raid56_end_io(struct bio *bio)
@@ -354,6 +401,9 @@ static void btrfs_raid56_end_io(struct bio *bio)
 	struct btrfs_io_context *bioc = bio->bi_private;
 	struct btrfs_bio *bbio = btrfs_bio(bio);
 
+	/* RAID56 endio is always handled in workqueue. */
+	ASSERT(in_task());
+
 	btrfs_bio_counter_dec(bioc->fs_info);
 	bbio->mirror_num = bioc->mirror_num;
 	if (bio_op(bio) == REQ_OP_READ && is_data_bbio(bbio))
@@ -364,11 +414,12 @@ static void btrfs_raid56_end_io(struct bio *bio)
 	btrfs_put_bioc(bioc);
 }
 
-static void btrfs_orig_write_end_io(struct bio *bio)
+static void orig_write_end_io_work(struct work_struct *work)
 {
+	struct btrfs_bio *bbio = container_of(work, struct btrfs_bio, end_io_work);
+	struct bio *bio = &bbio->bio;
 	struct btrfs_io_stripe *stripe = bio->bi_private;
 	struct btrfs_io_context *bioc = stripe->bioc;
-	struct btrfs_bio *bbio = btrfs_bio(bio);
 
 	btrfs_bio_counter_dec(bioc->fs_info);
 
@@ -393,8 +444,18 @@ static void btrfs_orig_write_end_io(struct bio *bio)
 	btrfs_put_bioc(bioc);
 }
 
-static void btrfs_clone_write_end_io(struct bio *bio)
+static void btrfs_orig_write_end_io(struct bio *bio)
 {
+	struct btrfs_bio *bbio = btrfs_bio(bio);
+
+	INIT_WORK(&bbio->end_io_work, orig_write_end_io_work);
+	queue_work(btrfs_end_io_wq(bbio->inode->root->fs_info, bio), &bbio->end_io_work);
+}
+
+static void clone_write_end_io_work(struct work_struct *work)
+{
+	struct btrfs_bio *bbio = container_of(work, struct btrfs_bio, end_io_work);
+	struct bio *bio = &bbio->bio;
 	struct btrfs_io_stripe *stripe = bio->bi_private;
 
 	if (bio->bi_status) {
@@ -409,6 +470,14 @@ static void btrfs_clone_write_end_io(struct bio *bio)
 	bio_put(bio);
 }
 
+static void btrfs_clone_write_end_io(struct bio *bio)
+{
+	struct btrfs_bio *bbio = btrfs_bio(bio);
+
+	INIT_WORK(&bbio->end_io_work, clone_write_end_io_work);
+	queue_work(btrfs_end_io_wq(bbio->inode->root->fs_info, bio), &bbio->end_io_work);
+}
+
 static void btrfs_submit_dev_bio(struct btrfs_device *dev, struct bio *bio)
 {
 	if (!dev || !dev->bdev ||
@@ -455,6 +524,7 @@ static void btrfs_submit_dev_bio(struct btrfs_device *dev, struct bio *bio)
 static void btrfs_submit_mirrored_bio(struct btrfs_io_context *bioc, int dev_nr)
 {
 	struct bio *orig_bio = bioc->orig_bio, *bio;
+	struct btrfs_bio *orig_bbio = btrfs_bio(orig_bio);
 
 	ASSERT(bio_op(orig_bio) != REQ_OP_READ);
 
@@ -463,8 +533,11 @@ static void btrfs_submit_mirrored_bio(struct btrfs_io_context *bioc, int dev_nr)
 		bio = orig_bio;
 		bio->bi_end_io = btrfs_orig_write_end_io;
 	} else {
-		bio = bio_alloc_clone(NULL, orig_bio, GFP_NOFS, &fs_bio_set);
+		/* We need to use endio_work to run end_io in task context. */
+		bio = bio_alloc_clone(NULL, orig_bio, GFP_NOFS, &btrfs_bioset);
 		bio_inc_remaining(orig_bio);
+		btrfs_bio_init(btrfs_bio(bio), orig_bbio->inode,
+			       orig_bbio->file_offset, NULL, NULL);
 		bio->bi_end_io = btrfs_clone_write_end_io;
 	}
 
@@ -509,7 +582,11 @@ static int btrfs_bio_csum(struct btrfs_bio *bbio)
 {
 	if (bbio->bio.bi_opf & REQ_META)
 		return btree_csum_one_bio(bbio);
-	return btrfs_csum_one_bio(bbio);
+#ifdef CONFIG_BTRFS_EXPERIMENTAL
+	return btrfs_csum_one_bio(bbio, true);
+#else
+	return btrfs_csum_one_bio(bbio, false);
+#endif
 }
 
 /*
@@ -581,20 +658,25 @@ static void run_one_async_done(struct btrfs_work *work, bool do_free)
 
 static bool should_async_write(struct btrfs_bio *bbio)
 {
+	struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
 	bool auto_csum_mode = true;
 
 #ifdef CONFIG_BTRFS_EXPERIMENTAL
-	struct btrfs_fs_devices *fs_devices = bbio->fs_info->fs_devices;
+	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 	enum btrfs_offload_csum_mode csum_mode = READ_ONCE(fs_devices->offload_csum_mode);
 
-	if (csum_mode == BTRFS_OFFLOAD_CSUM_FORCE_OFF)
-		return false;
-
-	auto_csum_mode = (csum_mode == BTRFS_OFFLOAD_CSUM_AUTO);
+	if (csum_mode == BTRFS_OFFLOAD_CSUM_FORCE_ON)
+		return true;
+	/*
+	 * Write bios will calculate checksum and submit bio at the same time.
+	 * Unless explicitly required don't offload serial csum calculate and bio
+	 * submit into a workqueue.
+	 */
+	return false;
 #endif
 
 	/* Submit synchronously if the checksum implementation is fast. */
-	if (auto_csum_mode && test_bit(BTRFS_FS_CSUM_IMPL_FAST, &bbio->fs_info->flags))
+	if (auto_csum_mode && test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))
 		return false;
 
 	/*
@@ -605,7 +687,7 @@ static bool should_async_write(struct btrfs_bio *bbio)
 		return false;
 
 	/* Zoned devices require I/O to be submitted in order. */
-	if ((bbio->bio.bi_opf & REQ_META) && btrfs_is_zoned(bbio->fs_info))
+	if ((bbio->bio.bi_opf & REQ_META) && btrfs_is_zoned(fs_info))
 		return false;
 
 	return true;
@@ -620,7 +702,7 @@ static bool btrfs_wq_submit_bio(struct btrfs_bio *bbio,
 				struct btrfs_io_context *bioc,
 				struct btrfs_io_stripe *smap, int mirror_num)
 {
-	struct btrfs_fs_info *fs_info = bbio->fs_info;
+	struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
 	struct async_submit_bio *async;
 
 	async = kmalloc(sizeof(*async), GFP_NOFS);
@@ -639,11 +721,12 @@ static bool btrfs_wq_submit_bio(struct btrfs_bio *bbio,
 
 static u64 btrfs_append_map_length(struct btrfs_bio *bbio, u64 map_length)
 {
+	struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
 	unsigned int nr_segs;
 	int sector_offset;
 
-	map_length = min(map_length, bbio->fs_info->max_zone_append_size);
-	sector_offset = bio_split_rw_at(&bbio->bio, &bbio->fs_info->limits,
+	map_length = min(map_length, fs_info->max_zone_append_size);
+	sector_offset = bio_split_rw_at(&bbio->bio, &fs_info->limits,
 					&nr_segs, map_length);
 	if (sector_offset) {
 		/*
@@ -651,7 +734,7 @@ static u64 btrfs_append_map_length(struct btrfs_bio *bbio, u64 map_length)
 		 * sectorsize and thus cause unaligned I/Os.  Fix that by
 		 * always rounding down to the nearest boundary.
 		 */
-		return ALIGN_DOWN(sector_offset << SECTOR_SHIFT, bbio->fs_info->sectorsize);
+		return ALIGN_DOWN(sector_offset << SECTOR_SHIFT, fs_info->sectorsize);
 	}
 	return map_length;
 }
@@ -659,7 +742,7 @@ static u64 btrfs_append_map_length(struct btrfs_bio *bbio, u64 map_length)
 static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
 {
 	struct btrfs_inode *inode = bbio->inode;
-	struct btrfs_fs_info *fs_info = bbio->fs_info;
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	struct bio *bio = &bbio->bio;
 	u64 logical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
 	u64 length = bio->bi_iter.bi_size;
@@ -670,7 +753,7 @@ static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
 	blk_status_t status;
 	int ret;
 
-	if (!bbio->inode || btrfs_is_data_reloc_root(inode->root))
+	if (bbio->is_scrub || btrfs_is_data_reloc_root(inode->root))
 		smap.rst_search_commit_root = true;
 	else
 		smap.rst_search_commit_root = false;
@@ -684,6 +767,14 @@ static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
 		goto end_bbio;
 	}
 
+	/*
+	 * For fscrypt writes we will get the encrypted bio after we've remapped
+	 * our bio to the physical disk location, so we need to save the
+	 * original bytenr so we know what we're checksumming.
+	 */
+	if (bio_op(bio) == REQ_OP_WRITE && is_data_bbio(bbio))
+		bbio->orig_logical = logical;
+
 	map_length = min(map_length, length);
 	if (use_append)
 		map_length = btrfs_append_map_length(bbio, map_length);
@@ -734,7 +825,7 @@ static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
 		 * Csum items for reloc roots have already been cloned at this
 		 * point, so they are handled as part of the no-checksum case.
 		 */
-		if (inode && !(inode->flags & BTRFS_INODE_NODATASUM) &&
+		if (!(inode->flags & BTRFS_INODE_NODATASUM) &&
 		    !test_bit(BTRFS_FS_STATE_NO_DATA_CSUMS, &fs_info->fs_state) &&
 		    !btrfs_is_data_reloc_root(inode->root)) {
 			if (should_async_write(bbio) &&
@@ -782,25 +873,27 @@ end_bbio:
 static void assert_bbio_alignment(struct btrfs_bio *bbio)
 {
 #ifdef CONFIG_BTRFS_ASSERT
-	struct btrfs_fs_info *fs_info = bbio->fs_info;
+	struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
 	struct bio_vec bvec;
 	struct bvec_iter iter;
 	const u32 blocksize = fs_info->sectorsize;
+	const u32 alignment = min(blocksize, PAGE_SIZE);
+	const u64 logical = bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT;
+	const u32 length = bbio->bio.bi_iter.bi_size;
 
-	/* Metadata has no extra bs > ps alignment requirement. */
-	if (!is_data_bbio(bbio))
-		return;
+	/* The logical and length should still be aligned to blocksize. */
+	ASSERT(IS_ALIGNED(logical, blocksize) && IS_ALIGNED(length, blocksize) &&
+	       length != 0, "root=%llu inode=%llu logical=%llu length=%u",
+	       btrfs_root_id(bbio->inode->root),
+	       btrfs_ino(bbio->inode), logical, length);
 
 	bio_for_each_bvec(bvec, &bbio->bio, iter)
-		ASSERT(IS_ALIGNED(bvec.bv_offset, blocksize) &&
-		       IS_ALIGNED(bvec.bv_len, blocksize),
+		ASSERT(IS_ALIGNED(bvec.bv_offset, alignment) &&
+		       IS_ALIGNED(bvec.bv_len, alignment),
 		"root=%llu inode=%llu logical=%llu length=%u index=%u bv_offset=%u bv_len=%u",
 		btrfs_root_id(bbio->inode->root),
-		btrfs_ino(bbio->inode),
-		bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT,
-		bbio->bio.bi_iter.bi_size, iter.bi_idx,
-		bvec.bv_offset,
-		bvec.bv_len);
+		btrfs_ino(bbio->inode), logical, length, iter.bi_idx,
+		bvec.bv_offset, bvec.bv_len);
 #endif
 }
 
@@ -824,18 +917,36 @@ void btrfs_submit_bbio(struct btrfs_bio *bbio, int mirror_num)
  *
  * The I/O is issued synchronously to block the repair read completion from
  * freeing the bio.
+ *
+ * @ino:	Offending inode number
+ * @fileoff:	File offset inside the inode
+ * @length:	Length of the repair write
+ * @logical:	Logical address of the range
+ * @paddrs:	Physical address array of the content
+ * @step:	Length of for each paddrs
+ * @mirror_num: Mirror number to write to. Must not be zero
  */
-int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
-			    u64 length, u64 logical, phys_addr_t paddr, int mirror_num)
+int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 fileoff,
+			    u32 length, u64 logical, const phys_addr_t paddrs[],
+			    unsigned int step, int mirror_num)
 {
+	const u32 nr_steps = DIV_ROUND_UP_POW2(length, step);
 	struct btrfs_io_stripe smap = { 0 };
-	struct bio_vec bvec;
-	struct bio bio;
+	struct bio *bio = NULL;
 	int ret = 0;
 
 	ASSERT(!(fs_info->sb->s_flags & SB_RDONLY));
 	BUG_ON(!mirror_num);
 
+	/* Basic alignment checks. */
+	ASSERT(IS_ALIGNED(logical, fs_info->sectorsize));
+	ASSERT(IS_ALIGNED(length, fs_info->sectorsize));
+	ASSERT(IS_ALIGNED(fileoff, fs_info->sectorsize));
+	/* Either it's a single data or metadata block. */
+	ASSERT(length <= BTRFS_MAX_BLOCKSIZE);
+	ASSERT(step <= length);
+	ASSERT(is_power_of_2(step));
+
 	if (btrfs_repair_one_zone(fs_info, logical))
 		return 0;
 
@@ -855,24 +966,27 @@ int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
 		goto out_counter_dec;
 	}
 
-	bio_init(&bio, smap.dev->bdev, &bvec, 1, REQ_OP_WRITE | REQ_SYNC);
-	bio.bi_iter.bi_sector = smap.physical >> SECTOR_SHIFT;
-	__bio_add_page(&bio, phys_to_page(paddr), length, offset_in_page(paddr));
-	ret = submit_bio_wait(&bio);
+	bio = bio_alloc(smap.dev->bdev, nr_steps, REQ_OP_WRITE | REQ_SYNC, GFP_NOFS);
+	bio->bi_iter.bi_sector = smap.physical >> SECTOR_SHIFT;
+	for (int i = 0; i < nr_steps; i++) {
+		ret = bio_add_page(bio, phys_to_page(paddrs[i]), step, offset_in_page(paddrs[i]));
+		/* We should have allocated enough slots to contain all the different pages. */
+		ASSERT(ret == step);
+	}
+	ret = submit_bio_wait(bio);
+	bio_put(bio);
 	if (ret) {
 		/* try to remap that extent elsewhere? */
 		btrfs_dev_stat_inc_and_print(smap.dev, BTRFS_DEV_STAT_WRITE_ERRS);
-		goto out_bio_uninit;
+		goto out_counter_dec;
 	}
 
 	btrfs_info_rl(fs_info,
 		"read error corrected: ino %llu off %llu (dev %s sector %llu)",
-			     ino, start, btrfs_dev_name(smap.dev),
+			     ino, fileoff, btrfs_dev_name(smap.dev),
 			     smap.physical >> SECTOR_SHIFT);
 	ret = 0;
 
-out_bio_uninit:
-	bio_uninit(&bio);
 out_counter_dec:
 	btrfs_bio_counter_dec(fs_info);
 	return ret;
@@ -885,16 +999,16 @@ out_counter_dec:
  */
 void btrfs_submit_repair_write(struct btrfs_bio *bbio, int mirror_num, bool dev_replace)
 {
-	struct btrfs_fs_info *fs_info = bbio->fs_info;
+	struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
 	u64 logical = bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT;
 	u64 length = bbio->bio.bi_iter.bi_size;
 	struct btrfs_io_stripe smap = { 0 };
 	int ret;
 
-	ASSERT(fs_info);
 	ASSERT(mirror_num > 0);
 	ASSERT(btrfs_op(&bbio->bio) == BTRFS_MAP_WRITE);
-	ASSERT(!bbio->inode);
+	ASSERT(!is_data_inode(bbio->inode));
+	ASSERT(bbio->is_scrub);
 
 	btrfs_bio_counter_inc_blocked(fs_info);
 	ret = btrfs_map_repair_block(fs_info, &smap, logical, length, mirror_num);