6.17-stable review patch. If anyone has any objections, please let me know.
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From: Keith Busch kbusch@kernel.org
[ Upstream commit fec2e705729dc93de5399d8b139e4746805c3d81 ]
We're already iterating every segment, so check these for a valid IO lengths at the same time. Individual segment lengths will not be checked on passthrough commands. The read/write command segments must be sized to the dma alignment.
Signed-off-by: Keith Busch kbusch@kernel.org Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-map.c | 2 +- block/blk-merge.c | 21 +++++++++++++++++---- include/linux/bio.h | 4 ++-- include/linux/blkdev.h | 7 +++++++ 4 files changed, 27 insertions(+), 7 deletions(-)
diff --git a/block/blk-map.c b/block/blk-map.c index 23e5d5ebe59ec..6d1268aa82715 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -443,7 +443,7 @@ int blk_rq_append_bio(struct request *rq, struct bio *bio) int ret;
/* check that the data layout matches the hardware restrictions */ - ret = bio_split_rw_at(bio, lim, &nr_segs, max_bytes); + ret = bio_split_io_at(bio, lim, &nr_segs, max_bytes, 0); if (ret) { /* if we would have to split the bio, copy instead */ if (ret > 0) diff --git a/block/blk-merge.c b/block/blk-merge.c index 77488f11a9441..37864c5d287ef 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -303,25 +303,30 @@ static unsigned int bio_split_alignment(struct bio *bio, }
/** - * bio_split_rw_at - check if and where to split a read/write bio + * bio_split_io_at - check if and where to split a bio * @bio: [in] bio to be split * @lim: [in] queue limits to split based on * @segs: [out] number of segments in the bio with the first half of the sectors * @max_bytes: [in] maximum number of bytes per bio + * @len_align_mask: [in] length alignment mask for each vector * * Find out if @bio needs to be split to fit the queue limits in @lim and a * maximum size of @max_bytes. Returns a negative error number if @bio can't be * split, 0 if the bio doesn't have to be split, or a positive sector offset if * @bio needs to be split. */ -int bio_split_rw_at(struct bio *bio, const struct queue_limits *lim, - unsigned *segs, unsigned max_bytes) +int bio_split_io_at(struct bio *bio, const struct queue_limits *lim, + unsigned *segs, unsigned max_bytes, unsigned len_align_mask) { struct bio_vec bv, bvprv, *bvprvp = NULL; struct bvec_iter iter; unsigned nsegs = 0, bytes = 0;
bio_for_each_bvec(bv, bio, iter) { + if (bv.bv_offset & lim->dma_alignment || + bv.bv_len & len_align_mask) + return -EINVAL; + /* * If the queue doesn't support SG gaps and adding this * offset would create a gap, disallow it. @@ -363,8 +368,16 @@ int bio_split_rw_at(struct bio *bio, const struct queue_limits *lim, * Individual bvecs might not be logical block aligned. Round down the * split size so that each bio is properly block size aligned, even if * we do not use the full hardware limits. + * + * It is possible to submit a bio that can't be split into a valid io: + * there may either be too many discontiguous vectors for the max + * segments limit, or contain virtual boundary gaps without having a + * valid block sized split. A zero byte result means one of those + * conditions occured. */ bytes = ALIGN_DOWN(bytes, bio_split_alignment(bio, lim)); + if (!bytes) + return -EINVAL;
/* * Bio splitting may cause subtle trouble such as hang when doing sync @@ -374,7 +387,7 @@ int bio_split_rw_at(struct bio *bio, const struct queue_limits *lim, bio_clear_polled(bio); return bytes >> SECTOR_SHIFT; } -EXPORT_SYMBOL_GPL(bio_split_rw_at); +EXPORT_SYMBOL_GPL(bio_split_io_at);
struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, unsigned *nr_segs) diff --git a/include/linux/bio.h b/include/linux/bio.h index 46ffac5caab78..519a1d59805f8 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -322,8 +322,8 @@ static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio) void bio_trim(struct bio *bio, sector_t offset, sector_t size); extern struct bio *bio_split(struct bio *bio, int sectors, gfp_t gfp, struct bio_set *bs); -int bio_split_rw_at(struct bio *bio, const struct queue_limits *lim, - unsigned *segs, unsigned max_bytes); +int bio_split_io_at(struct bio *bio, const struct queue_limits *lim, + unsigned *segs, unsigned max_bytes, unsigned len_align);
/** * bio_next_split - get next @sectors from a bio, splitting if necessary diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index cc221318712e7..37fa7169fa9f4 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1872,6 +1872,13 @@ bdev_atomic_write_unit_max_bytes(struct block_device *bdev) return queue_atomic_write_unit_max_bytes(bdev_get_queue(bdev)); }
+static inline int bio_split_rw_at(struct bio *bio, + const struct queue_limits *lim, + unsigned *segs, unsigned max_bytes) +{ + return bio_split_io_at(bio, lim, segs, max_bytes, lim->dma_alignment); +} + #define DEFINE_IO_COMP_BATCH(name) struct io_comp_batch name = { }
#endif /* _LINUX_BLKDEV_H */