From: Stanley Zhang stazhang@purestorage.com
Add a function ublk_copy_user_integrity() to copy integrity information between a request and a user iov_iter. This mirrors the existing ublk_copy_user_pages() but operates on request integrity data instead of regular data. Check UBLKSRV_IO_INTEGRITY_FLAG in iocb->ki_pos in ublk_user_copy() to choose between copying data or integrity data.
Signed-off-by: Stanley Zhang stazhang@purestorage.com [csander: change offset units from data bytes to integrity data bytes, fix CONFIG_BLK_DEV_INTEGRITY=n build, rebase on user copy refactor] Signed-off-by: Caleb Sander Mateos csander@purestorage.com --- drivers/block/ublk_drv.c | 53 +++++++++++++++++++++++++++++++++-- include/uapi/linux/ublk_cmd.h | 4 +++ 2 files changed, 55 insertions(+), 2 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 8eefb838b563..2a8a6a9c0281 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -1052,10 +1052,37 @@ static size_t ublk_copy_user_pages(const struct request *req, break; } return done; }
+#ifdef CONFIG_BLK_DEV_INTEGRITY +static size_t ublk_copy_user_integrity(const struct request *req, + unsigned offset, struct iov_iter *uiter, int dir) +{ + size_t done = 0; + struct bio *bio = req->bio; + struct bvec_iter iter; + struct bio_vec iv; + + if (!blk_integrity_rq(req)) + return 0; + + bio_for_each_integrity_vec(iv, bio, iter) { + if (!ublk_copy_user_bvec(&iv, &offset, uiter, dir, &done)) + break; + } + + return done; +} +#else /* #ifdef CONFIG_BLK_DEV_INTEGRITY */ +static size_t ublk_copy_user_integrity(const struct request *req, + unsigned offset, struct iov_iter *uiter, int dir) +{ + return 0; +} +#endif /* #ifdef CONFIG_BLK_DEV_INTEGRITY */ + static inline bool ublk_need_map_req(const struct request *req) { return ublk_rq_has_data(req) && req_op(req) == REQ_OP_WRITE; }
@@ -2659,10 +2686,12 @@ ublk_user_copy(struct kiocb *iocb, struct iov_iter *iter, int dir) { struct ublk_device *ub = iocb->ki_filp->private_data; struct ublk_queue *ubq; struct request *req; struct ublk_io *io; + unsigned data_len; + bool is_integrity; size_t buf_off; u16 tag, q_id; ssize_t ret;
if (!user_backed_iter(iter)) @@ -2672,10 +2701,14 @@ ublk_user_copy(struct kiocb *iocb, struct iov_iter *iter, int dir) return -EACCES;
tag = ublk_pos_to_tag(iocb->ki_pos); q_id = ublk_pos_to_hwq(iocb->ki_pos); buf_off = ublk_pos_to_buf_off(iocb->ki_pos); + is_integrity = !!(iocb->ki_pos & UBLKSRV_IO_INTEGRITY_FLAG); + + if (unlikely(!ublk_dev_support_integrity(ub) && is_integrity)) + return -EINVAL;
if (q_id >= ub->dev_info.nr_hw_queues) return -EINVAL;
ubq = ublk_get_queue(ub, q_id); @@ -2688,21 +2721,31 @@ ublk_user_copy(struct kiocb *iocb, struct iov_iter *iter, int dir) io = &ubq->ios[tag]; req = __ublk_check_and_get_req(ub, q_id, tag, io); if (!req) return -EINVAL;
- if (buf_off > blk_rq_bytes(req)) { + if (is_integrity) { + struct blk_integrity *bi = &req->q->limits.integrity; + + data_len = bio_integrity_bytes(bi, blk_rq_sectors(req)); + } else { + data_len = blk_rq_bytes(req); + } + if (buf_off > data_len) { ret = -EINVAL; goto out; }
if (!ublk_check_ubuf_dir(req, dir)) { ret = -EACCES; goto out; }
- ret = ublk_copy_user_pages(req, buf_off, iter, dir); + if (is_integrity) + ret = ublk_copy_user_integrity(req, buf_off, iter, dir); + else + ret = ublk_copy_user_pages(req, buf_off, iter, dir);
out: ublk_put_req_ref(io, req); return ret; } @@ -3939,10 +3982,16 @@ static int __init ublk_init(void) { int ret;
BUILD_BUG_ON((u64)UBLKSRV_IO_BUF_OFFSET + UBLKSRV_IO_BUF_TOTAL_SIZE < UBLKSRV_IO_BUF_OFFSET); + /* + * Ensure UBLKSRV_IO_BUF_OFFSET + UBLKSRV_IO_BUF_TOTAL_SIZE + * doesn't overflow into UBLKSRV_IO_INTEGRITY_FLAG + */ + BUILD_BUG_ON(UBLKSRV_IO_BUF_OFFSET + UBLKSRV_IO_BUF_TOTAL_SIZE >= + UBLKSRV_IO_INTEGRITY_FLAG); BUILD_BUG_ON(sizeof(struct ublk_auto_buf_reg) != 8);
init_waitqueue_head(&ublk_idr_wq);
ret = misc_register(&ublk_misc); diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h index dfde4aee39eb..61ac5d8e1078 100644 --- a/include/uapi/linux/ublk_cmd.h +++ b/include/uapi/linux/ublk_cmd.h @@ -132,10 +132,14 @@ #define UBLK_MAX_NR_QUEUES (1U << UBLK_QID_BITS)
#define UBLKSRV_IO_BUF_TOTAL_BITS (UBLK_QID_OFF + UBLK_QID_BITS) #define UBLKSRV_IO_BUF_TOTAL_SIZE (1ULL << UBLKSRV_IO_BUF_TOTAL_BITS)
+/* Copy to/from request integrity buffer instead of data buffer */ +#define UBLK_INTEGRITY_FLAG_OFF 62 +#define UBLKSRV_IO_INTEGRITY_FLAG (1ULL << UBLK_INTEGRITY_FLAG_OFF) + /* * ublk server can register data buffers for incoming I/O requests with a sparse * io_uring buffer table. The request buffer can then be used as the data buffer * for io_uring operations via the fixed buffer index. * Note that the ublk server can never directly access the request data memory.