Commit 32d5019e authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: pass a minsize argument to bio_iov_iter_bounce 



When bouncing for block size > PAGE_SIZE file systems that require
file system block size alignment (e.g. zoned XFS), the bio needs to
be big enough to fit an entire block.

Fixes: 8dd5e7c7 ("block: add helpers to bounce buffer an iov_iter into bios")
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarHannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260507050153.1298375-2-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 87d0740b

block/bio.c

+13 −10
Original line number Diff line number Diff line
@@ -1279,11 +1279,12 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter, 
	return bio_iov_iter_align_down(bio, iter, len_align_mask);

}



static struct folio *folio_alloc_greedy(gfp_t gfp, size_t *size)

static struct folio *folio_alloc_greedy(gfp_t gfp, size_t *size,

		size_t minsize)

{

	struct folio *folio;



	while (*size > PAGE_SIZE) {

	while (*size > minsize) {

		folio = folio_alloc(gfp | __GFP_NORETRY, get_order(*size));

		if (folio)

			return folio;
@@ -1307,7 +1308,7 @@ static void bio_free_folios(struct bio *bio) 
}



static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter,

		size_t maxlen)

		size_t maxlen, size_t minsize)

{

	size_t total_len = min(maxlen, iov_iter_count(iter));
@@ -1322,13 +1323,13 @@ static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter, 
		size_t this_len = min(total_len, SZ_1M);

		struct folio *folio;



		if (this_len > PAGE_SIZE * 2)

		if (this_len > minsize * 2)

			this_len = rounddown_pow_of_two(this_len);



		if (bio->bi_iter.bi_size > BIO_MAX_SIZE - this_len)

			break;



		folio = folio_alloc_greedy(GFP_KERNEL, &this_len);

		folio = folio_alloc_greedy(GFP_KERNEL, &this_len, minsize);

		if (!folio)

			break;

		bio_add_folio_nofail(bio, folio, this_len, 0);
@@ -1348,12 +1349,12 @@ static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter, 
}



static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter,

		size_t maxlen)

		size_t maxlen, size_t minsize)

{

	size_t len = min3(iov_iter_count(iter), maxlen, SZ_1M);

	struct folio *folio;



	folio = folio_alloc_greedy(GFP_KERNEL, &len);

	folio = folio_alloc_greedy(GFP_KERNEL, &len, minsize);

	if (!folio)

		return -ENOMEM;
@@ -1390,6 +1391,7 @@ static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter, 
 * @bio:	bio to send

 * @iter:	iter to read from / write into

 * @maxlen:	maximum size to bounce

 * @minsize:	minimum folio allocation size

 *

 * Helper for direct I/O implementations that need to bounce buffer because

 * we need to checksum the data or perform other operations that require
@@ -1397,11 +1399,12 @@ static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter, 
 * copies the data into it.  Needs to be paired with bio_iov_iter_unbounce()

 * called on completion.

 */

int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen)

int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen,

			size_t minsize)

{

	if (op_is_write(bio_op(bio)))

		return bio_iov_iter_bounce_write(bio, iter, maxlen);

	return bio_iov_iter_bounce_read(bio, iter, maxlen);

		return bio_iov_iter_bounce_write(bio, iter, maxlen, minsize);

	return bio_iov_iter_bounce_read(bio, iter, maxlen, minsize);

}



static void bvec_unpin(struct bio_vec *bv, bool mark_dirty)

fs/iomap/direct-io.c

+1 −1
Original line number Diff line number Diff line
@@ -355,7 +355,7 @@ static ssize_t iomap_dio_bio_iter_one(struct iomap_iter *iter, 


	if (dio->flags & IOMAP_DIO_BOUNCE)

		ret = bio_iov_iter_bounce(bio, dio->submit.iter,

				iomap_max_bio_size(&iter->iomap));

				iomap_max_bio_size(&iter->iomap), alignment);

	else

		ret = bio_iov_iter_get_pages(bio, dio->submit.iter,

					     alignment - 1);

include/linux/bio.h

+2 −1
Original line number Diff line number Diff line
@@ -475,7 +475,8 @@ void __bio_release_pages(struct bio *bio, bool mark_dirty); 
extern void bio_set_pages_dirty(struct bio *bio);

extern void bio_check_pages_dirty(struct bio *bio);



int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen);

int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen,

		size_t minsize);

void bio_iov_iter_unbounce(struct bio *bio, bool is_error, bool mark_dirty);



extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,