Commit 8d61ece1 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

ublk: add `union ublk_io_buf` with improved naming 



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: default avatarCaleb Sander Mateos <csander@purestorage.com>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 3035b9b4

drivers/block/ublk_drv.c

+22 −18
Original line number Diff line number Diff line
@@ -155,12 +155,13 @@ struct ublk_uring_cmd_pdu { 
 */

#define UBLK_REFCOUNT_INIT (REFCOUNT_MAX / 2)



struct ublk_io {

	/* userspace buffer address from io cmd */

	union {

union ublk_io_buf {

	__u64	addr;

		struct ublk_auto_buf_reg buf;

	struct ublk_auto_buf_reg auto_reg;

};



struct ublk_io {

	union ublk_io_buf buf;

	unsigned int flags;

	int res;
@@ -498,7 +499,7 @@ 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;

}
@@ -981,7 +982,7 @@ static unsigned int ublk_map_io(const struct ublk_queue *ubq, 
		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;
@@ -1002,7 +1003,7 @@ static unsigned 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;
@@ -1068,7 +1069,7 @@ 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;

}
@@ -1182,9 +1183,9 @@ 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;

		}
@@ -1473,7 +1474,7 @@ 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
@@ -2034,13 +2035,16 @@ 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;

}
@@ -2062,7 +2066,7 @@ 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);
@@ -2090,7 +2094,7 @@ 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;

}
@@ -2287,7 +2291,7 @@ 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);