Revert "bio: limit bio max size"block-5.13-2021-05-09

This reverts commit cd2c7545ae1beac3b6aae033c7f31193b3255946.

Alex reports that the commit causes corruption with LUKS on ext4. Revert
it for now so that this can be investigated properly.

Link: https://lore.kernel.org/linux-block/1620493841.bxdq8r5haw.none@localhost/
Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

4 files changed, 3 insertions, 21 deletions

diff --git a/block/bio.c b/block/bio.c
index 221dc56ba22f..44205dfb6b60 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -255,13 +255,6 @@ void bio_init(struct bio *bio, struct bio_vec *table,
 }
 EXPORT_SYMBOL(bio_init);
 
-unsigned int bio_max_size(struct bio *bio)
-{
-	struct block_device *bdev = bio->bi_bdev;
-
-	return bdev ? bdev->bd_disk->queue->limits.bio_max_bytes : UINT_MAX;
-}
-
 /**
  * bio_reset - reinitialize a bio
  * @bio:	bio to reset
@@ -873,7 +866,7 @@ bool __bio_try_merge_page(struct bio *bio, struct page *page,
 		struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
 
 		if (page_is_mergeable(bv, page, len, off, same_page)) {
-			if (bio->bi_iter.bi_size > bio_max_size(bio) - len) {
+			if (bio->bi_iter.bi_size > UINT_MAX - len) {
 				*same_page = false;
 				return false;
 			}
@@ -1002,7 +995,6 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
 {
 	unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt;
 	unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt;
-	unsigned int bytes_left = bio_max_size(bio) - bio->bi_iter.bi_size;
 	struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt;
 	struct page **pages = (struct page **)bv;
 	bool same_page = false;
@@ -1018,8 +1010,7 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
 	BUILD_BUG_ON(PAGE_PTRS_PER_BVEC < 2);
 	pages += entries_left * (PAGE_PTRS_PER_BVEC - 1);
 
-	size = iov_iter_get_pages(iter, pages, bytes_left, nr_pages,
-				  &offset);
+	size = iov_iter_get_pages(iter, pages, LONG_MAX, nr_pages, &offset);
 	if (unlikely(size <= 0))
 		return size ? size : -EFAULT;
 
diff --git a/block/blk-settings.c b/block/blk-settings.c
index c646503e55d2..9c009090c4b5 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -31,7 +31,6 @@ EXPORT_SYMBOL_GPL(blk_queue_rq_timeout);
  */
 void blk_set_default_limits(struct queue_limits *lim)
 {
-	lim->bio_max_bytes = UINT_MAX;
 	lim->max_segments = BLK_MAX_SEGMENTS;
 	lim->max_discard_segments = 1;
 	lim->max_integrity_segments = 0;
@@ -140,10 +139,6 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto
 				 limits->logical_block_size >> SECTOR_SHIFT);
 	limits->max_sectors = max_sectors;
 
-	if (check_shl_overflow(max_sectors, SECTOR_SHIFT,
-				&limits->bio_max_bytes))
-		limits->bio_max_bytes = UINT_MAX;
-
 	q->backing_dev_info->io_pages = max_sectors >> (PAGE_SHIFT - 9);
 }
 EXPORT_SYMBOL(blk_queue_max_hw_sectors);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index f1a99f0a240c..a0b4cfdf62a4 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -106,8 +106,6 @@ static inline void *bio_data(struct bio *bio)
 	return NULL;
 }
 
-extern unsigned int bio_max_size(struct bio *bio);
-
 /**
  * bio_full - check if the bio is full
  * @bio:	bio to check
@@ -121,7 +119,7 @@ static inline bool bio_full(struct bio *bio, unsigned len)
 	if (bio->bi_vcnt >= bio->bi_max_vecs)
 		return true;
 
-	if (bio->bi_iter.bi_size > bio_max_size(bio) - len)
+	if (bio->bi_iter.bi_size > UINT_MAX - len)
 		return true;
 
 	return false;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 40c7c4d87aa1..b91ba6207365 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -327,8 +327,6 @@ enum blk_bounce {
 };
 
 struct queue_limits {
-	unsigned int		bio_max_bytes;
-
 	enum blk_bounce		bounce;
 	unsigned long		seg_boundary_mask;
 	unsigned long		virt_boundary_mask;