Commit f688944c authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring/rw: add separate prep handler for fixed read/write 



Rather than sprinkle opcode checks in the generic read/write prep handler,
have a separate prep handler for the vectored readv/writev operation.

Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 0e984ec8

io_uring/opdef.c

+2 −2
Original line number Diff line number Diff line
@@ -98,7 +98,7 @@ const struct io_issue_def io_issue_defs[] = { 
		.ioprio			= 1,

		.iopoll			= 1,

		.iopoll_queue		= 1,

		.prep			= io_prep_rw,

		.prep			= io_prep_rw_fixed,

		.issue			= io_read,

	},

	[IORING_OP_WRITE_FIXED] = {
@@ -111,7 +111,7 @@ const struct io_issue_def io_issue_defs[] = { 
		.ioprio			= 1,

		.iopoll			= 1,

		.iopoll_queue		= 1,

		.prep			= io_prep_rw,

		.prep			= io_prep_rw_fixed,

		.issue			= io_write,

	},

	[IORING_OP_POLL_ADD] = {

io_uring/rw.c

+18 −12
Original line number Diff line number Diff line
@@ -83,18 +83,6 @@ int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) 
	/* used for fixed read/write too - just read unconditionally */

	req->buf_index = READ_ONCE(sqe->buf_index);



	if (req->opcode == IORING_OP_READ_FIXED ||

	    req->opcode == IORING_OP_WRITE_FIXED) {

		struct io_ring_ctx *ctx = req->ctx;

		u16 index;



		if (unlikely(req->buf_index >= ctx->nr_user_bufs))

			return -EFAULT;

		index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);

		req->imu = ctx->user_bufs[index];

		io_req_set_rsrc_node(req, ctx, 0);

	}



	ioprio = READ_ONCE(sqe->ioprio);

	if (ioprio) {

		ret = ioprio_check_cap(ioprio);
@@ -131,6 +119,24 @@ int io_prep_rwv(struct io_kiocb *req, const struct io_uring_sqe *sqe) 
	return 0;

}



int io_prep_rw_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe)

{

	struct io_ring_ctx *ctx = req->ctx;

	u16 index;

	int ret;



	ret = io_prep_rw(req, sqe);

	if (unlikely(ret))

		return ret;



	if (unlikely(req->buf_index >= ctx->nr_user_bufs))

		return -EFAULT;

	index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);

	req->imu = ctx->user_bufs[index];

	io_req_set_rsrc_node(req, ctx, 0);

	return 0;

}



/*

 * Multishot read is prepared just like a normal read/write request, only

 * difference is that we set the MULTISHOT flag.

io_uring/rw.h

+1 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ struct io_async_rw { 


int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe);

int io_prep_rwv(struct io_kiocb *req, const struct io_uring_sqe *sqe);

int io_prep_rw_fixed(struct io_kiocb *req, const struct io_uring_sqe *sqe);

int io_read(struct io_kiocb *req, unsigned int issue_flags);

int io_readv_prep_async(struct io_kiocb *req);

int io_write(struct io_kiocb *req, unsigned int issue_flags);