diff options
| author | Christoph Hellwig <hch@lst.de> | 2025-05-07 14:04:26 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-05-07 07:31:07 -0600 |
| commit | 10b1e59cdadabff16fc78eb2ca4c341b1502293c (patch) | |
| tree | b3b028ec44f1eb48b8ac5fec40d309c2f59a9d1a | |
| parent | 850e210d5ad21b94b55b97d4d82b4cdeb0bb05df (diff) | |
block: add a bdev_rw_virt helper
Add a helper to perform synchronous I/O on a kernel direct map range.
Currently this is implemented in various places in usually not very
efficient ways, so provide a generic helper instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250507120451.4000627-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/bio.c | 30 | ||||
| -rw-r--r-- | include/linux/bio.h | 5 |
2 files changed, 34 insertions, 1 deletions
diff --git a/block/bio.c b/block/bio.c index bd3d048d0a72..26782ff85dbf 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1319,6 +1319,36 @@ int submit_bio_wait(struct bio *bio) } EXPORT_SYMBOL(submit_bio_wait); +/** + * bdev_rw_virt - synchronously read into / write from kernel mapping + * @bdev: block device to access + * @sector: sector to access + * @data: data to read/write + * @len: length in byte to read/write + * @op: operation (e.g. REQ_OP_READ/REQ_OP_WRITE) + * + * Performs synchronous I/O to @bdev for @data/@len. @data must be in + * the kernel direct mapping and not a vmalloc address. + */ +int bdev_rw_virt(struct block_device *bdev, sector_t sector, void *data, + size_t len, enum req_op op) +{ + struct bio_vec bv; + struct bio bio; + int error; + + if (WARN_ON_ONCE(is_vmalloc_addr(data))) + return -EIO; + + bio_init(&bio, bdev, &bv, 1, op); + bio.bi_iter.bi_sector = sector; + bio_add_virt_nofail(&bio, data, len); + error = submit_bio_wait(&bio); + bio_uninit(&bio); + return error; +} +EXPORT_SYMBOL_GPL(bdev_rw_virt); + static void bio_wait_end_io(struct bio *bio) { complete(bio->bi_private); diff --git a/include/linux/bio.h b/include/linux/bio.h index acca7464080c..ad54e6af20dc 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -402,7 +402,6 @@ static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs) struct request_queue; -extern int submit_bio_wait(struct bio *bio); void bio_init(struct bio *bio, struct block_device *bdev, struct bio_vec *table, unsigned short max_vecs, blk_opf_t opf); extern void bio_uninit(struct bio *); @@ -419,6 +418,10 @@ void bio_add_folio_nofail(struct bio *bio, struct folio *folio, size_t len, size_t off); void bio_add_virt_nofail(struct bio *bio, void *vaddr, unsigned len); +int submit_bio_wait(struct bio *bio); +int bdev_rw_virt(struct block_device *bdev, sector_t sector, void *data, + size_t len, enum req_op op); + int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); void bio_iov_bvec_set(struct bio *bio, const struct iov_iter *iter); void __bio_release_pages(struct bio *bio, bool mark_dirty); |