Allow the file system to limit the size processed in a single bounce operation. This is needed when generating integrity data so that the size of a single integrity segment can't overflow.
Signed-off-by: Christoph Hellwig <[email protected]> --- block/bio.c | 17 ++++++++++------- fs/iomap/direct-io.c | 2 +- include/linux/bio.h | 2 +- 3 files changed, 12 insertions(+), 9 deletions(-) diff --git a/block/bio.c b/block/bio.c index da795b1df52a..e89b24dc0283 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1293,9 +1293,10 @@ static void bio_free_folios(struct bio *bio) } } -static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter) +static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter, + size_t maxlen) { - size_t total_len = iov_iter_count(iter); + size_t total_len = min(maxlen, iov_iter_count(iter)); if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) return -EINVAL; @@ -1333,9 +1334,10 @@ static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter) return 0; } -static int bio_iov_iter_bounce_read(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 len = min(iov_iter_count(iter), SZ_1M); + size_t len = min3(iov_iter_count(iter), maxlen, SZ_1M); struct folio *folio; folio = folio_alloc_greedy(GFP_KERNEL, &len); @@ -1372,6 +1374,7 @@ static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter) * bio_iov_iter_bounce - bounce buffer data from an iter into a bio * @bio: bio to send * @iter: iter to read from / write into + * @maxlen: maximum size to bounce * * Helper for direct I/O implementations that need to bounce buffer because * we need to checksum the data or perform other operations that require @@ -1379,11 +1382,11 @@ 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) +int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen) { if (op_is_write(bio_op(bio))) - return bio_iov_iter_bounce_write(bio, iter); - return bio_iov_iter_bounce_read(bio, iter); + return bio_iov_iter_bounce_write(bio, iter, maxlen); + return bio_iov_iter_bounce_read(bio, iter, maxlen); } static void bvec_unpin(struct bio_vec *bv, bool mark_dirty) diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 9c572de0d596..842fc7fecb2d 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -326,7 +326,7 @@ static ssize_t iomap_dio_bio_iter_one(struct iomap_iter *iter, bio->bi_end_io = iomap_dio_bio_end_io; if (dio->flags & IOMAP_DIO_BOUNCE) - ret = bio_iov_iter_bounce(bio, dio->submit.iter); + ret = bio_iov_iter_bounce(bio, dio->submit.iter, UINT_MAX); else ret = bio_iov_iter_get_pages(bio, dio->submit.iter, alignment - 1); diff --git a/include/linux/bio.h b/include/linux/bio.h index 95cfc79b88b8..df0d7e71372a 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -479,7 +479,7 @@ 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); +int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen); 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, -- 2.47.3
