6.18-stable review patch. If anyone has any objections, please let me know.
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From: Ming Lei ming.lei@redhat.com
[ Upstream commit 8d61ece156bd4f2b9e7d3b2a374a26d42c7a4a06 ]
Add `union ublk_io_buf` for naming the anonymous union of struct ublk_io's addr and buf fields, meantime apply it to `struct ublk_io` for storing either ublk auto buffer register data or ublk server io buffer address.
The union uses clear field names: - `addr`: for regular ublk server io buffer addresses - `auto_reg`: for ublk auto buffer registration data
This eliminates confusing access patterns and improves code readability.
Reviewed-by: Caleb Sander Mateos csander@purestorage.com Signed-off-by: Ming Lei ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Stable-dep-of: c258f5c4502c ("ublk: fix deadlock when reading partition table") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/ublk_drv.c | 40 ++++++++++++++++++++++------------------ 1 file changed, 22 insertions(+), 18 deletions(-)
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 599571634b7a..c9d258b99090 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -155,12 +155,13 @@ struct ublk_uring_cmd_pdu { */ #define UBLK_REFCOUNT_INIT (REFCOUNT_MAX / 2)
+union ublk_io_buf { + __u64 addr; + struct ublk_auto_buf_reg auto_reg; +}; + struct ublk_io { - /* userspace buffer address from io cmd */ - union { - __u64 addr; - struct ublk_auto_buf_reg buf; - }; + union ublk_io_buf buf; unsigned int flags; int res;
@@ -499,7 +500,7 @@ static blk_status_t ublk_setup_iod_zoned(struct ublk_queue *ubq, iod->op_flags = ublk_op | ublk_req_build_flags(req); iod->nr_sectors = blk_rq_sectors(req); iod->start_sector = blk_rq_pos(req); - iod->addr = io->addr; + iod->addr = io->buf.addr;
return BLK_STS_OK; } @@ -1047,7 +1048,7 @@ static int ublk_map_io(const struct ublk_queue *ubq, const struct request *req, struct iov_iter iter; const int dir = ITER_DEST;
- import_ubuf(dir, u64_to_user_ptr(io->addr), rq_bytes, &iter); + import_ubuf(dir, u64_to_user_ptr(io->buf.addr), rq_bytes, &iter); return ublk_copy_user_pages(req, 0, &iter, dir); } return rq_bytes; @@ -1068,7 +1069,7 @@ static int ublk_unmap_io(bool need_map,
WARN_ON_ONCE(io->res > rq_bytes);
- import_ubuf(dir, u64_to_user_ptr(io->addr), io->res, &iter); + import_ubuf(dir, u64_to_user_ptr(io->buf.addr), io->res, &iter); return ublk_copy_user_pages(req, 0, &iter, dir); } return rq_bytes; @@ -1134,7 +1135,7 @@ static blk_status_t ublk_setup_iod(struct ublk_queue *ubq, struct request *req) iod->op_flags = ublk_op | ublk_req_build_flags(req); iod->nr_sectors = blk_rq_sectors(req); iod->start_sector = blk_rq_pos(req); - iod->addr = io->addr; + iod->addr = io->buf.addr;
return BLK_STS_OK; } @@ -1248,9 +1249,9 @@ static bool ublk_auto_buf_reg(const struct ublk_queue *ubq, struct request *req, int ret;
ret = io_buffer_register_bvec(cmd, req, ublk_io_release, - io->buf.index, issue_flags); + io->buf.auto_reg.index, issue_flags); if (ret) { - if (io->buf.flags & UBLK_AUTO_BUF_REG_FALLBACK) { + if (io->buf.auto_reg.flags & UBLK_AUTO_BUF_REG_FALLBACK) { ublk_auto_buf_reg_fallback(ubq, io); return true; } @@ -1539,7 +1540,7 @@ static void ublk_queue_reinit(struct ublk_device *ub, struct ublk_queue *ubq) */ io->flags &= UBLK_IO_FLAG_CANCELED; io->cmd = NULL; - io->addr = 0; + io->buf.addr = 0;
/* * old task is PF_EXITING, put it now @@ -2100,13 +2101,16 @@ static inline int ublk_check_cmd_op(u32 cmd_op)
static inline int ublk_set_auto_buf_reg(struct ublk_io *io, struct io_uring_cmd *cmd) { - io->buf = ublk_sqe_addr_to_auto_buf_reg(READ_ONCE(cmd->sqe->addr)); + struct ublk_auto_buf_reg buf; + + buf = ublk_sqe_addr_to_auto_buf_reg(READ_ONCE(cmd->sqe->addr));
- if (io->buf.reserved0 || io->buf.reserved1) + if (buf.reserved0 || buf.reserved1) return -EINVAL;
- if (io->buf.flags & ~UBLK_AUTO_BUF_REG_F_MASK) + if (buf.flags & ~UBLK_AUTO_BUF_REG_F_MASK) return -EINVAL; + io->buf.auto_reg = buf; return 0; }
@@ -2128,7 +2132,7 @@ static int ublk_handle_auto_buf_reg(struct ublk_io *io, * this ublk request gets stuck. */ if (io->buf_ctx_handle == io_uring_cmd_ctx_handle(cmd)) - *buf_idx = io->buf.index; + *buf_idx = io->buf.auto_reg.index; }
return ublk_set_auto_buf_reg(io, cmd); @@ -2156,7 +2160,7 @@ ublk_config_io_buf(const struct ublk_device *ub, struct ublk_io *io, if (ublk_dev_support_auto_buf_reg(ub)) return ublk_handle_auto_buf_reg(io, cmd, buf_idx);
- io->addr = buf_addr; + io->buf.addr = buf_addr; return 0; }
@@ -2353,7 +2357,7 @@ static bool ublk_get_data(const struct ublk_queue *ubq, struct ublk_io *io, */ io->flags &= ~UBLK_IO_FLAG_NEED_GET_DATA; /* update iod->addr because ublksrv may have passed a new io buffer */ - ublk_get_iod(ubq, req->tag)->addr = io->addr; + ublk_get_iod(ubq, req->tag)->addr = io->buf.addr; pr_devel("%s: update iod->addr: qid %d tag %d io_flags %x addr %llx\n", __func__, ubq->q_id, req->tag, io->flags, ublk_get_iod(ubq, req->tag)->addr);