Commit 8da11c19 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: add interface for getting files 



Preparation without functional changes. Adds io_get_file(), that allows
to grab files not only into req->file.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 444ebb57

fs/io_uring.c

+43 −29
Original line number Diff line number Diff line
@@ -1253,6 +1253,15 @@ static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx, 
	return NULL;

}



static inline void io_put_file(struct io_kiocb *req, struct file *file,

			  bool fixed)

{

	if (fixed)

		percpu_ref_put(&req->ctx->file_data->refs);

	else

		fput(file);

}



static void __io_req_do_free(struct io_kiocb *req)

{

	if (likely(!io_is_fallback_req(req)))
@@ -1263,18 +1272,12 @@ static void __io_req_do_free(struct io_kiocb *req) 


static void __io_req_aux_free(struct io_kiocb *req)

{

	struct io_ring_ctx *ctx = req->ctx;



	if (req->flags & REQ_F_NEED_CLEANUP)

		io_cleanup_req(req);



	kfree(req->io);

	if (req->file) {

		if (req->flags & REQ_F_FIXED_FILE)

			percpu_ref_put(&ctx->file_data->refs);

		else

			fput(req->file);

	}

	if (req->file)

		io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE));



	io_req_work_drop_env(req);

}
@@ -1848,7 +1851,7 @@ static void io_file_put(struct io_submit_state *state) 
 * assuming most submissions are for one file, or at least that each file

 * has more than one submission.

 */

static struct file *io_file_get(struct io_submit_state *state, int fd)

static struct file *__io_file_get(struct io_submit_state *state, int fd)

{

	if (!state)

		return fget(fd);
@@ -4578,41 +4581,52 @@ static inline struct file *io_file_from_index(struct io_ring_ctx *ctx, 
	return table->files[index & IORING_FILE_TABLE_MASK];;

}



static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,

			   const struct io_uring_sqe *sqe)

static int io_file_get(struct io_submit_state *state, struct io_kiocb *req,

			int fd, struct file **out_file, bool fixed)

{

	struct io_ring_ctx *ctx = req->ctx;

	unsigned flags;

	int fd;



	flags = READ_ONCE(sqe->flags);

	fd = READ_ONCE(sqe->fd);



	if (!io_req_needs_file(req, fd))

		return 0;

	struct file *file;



	if (flags & IOSQE_FIXED_FILE) {

	if (fixed) {

		if (unlikely(!ctx->file_data ||

		    (unsigned) fd >= ctx->nr_user_files))

			return -EBADF;

		fd = array_index_nospec(fd, ctx->nr_user_files);

		req->file = io_file_from_index(ctx, fd);

		if (!req->file)

		file = io_file_from_index(ctx, fd);

		if (!file)

			return -EBADF;

		req->flags |= REQ_F_FIXED_FILE;

		percpu_ref_get(&ctx->file_data->refs);

	} else {

		if (req->needs_fixed_file)

			return -EBADF;

		trace_io_uring_file_get(ctx, fd);

		req->file = io_file_get(state, fd);

		if (unlikely(!req->file))

		file = __io_file_get(state, fd);

		if (unlikely(!file))

			return -EBADF;

	}



	*out_file = file;

	return 0;

}



static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,

			   const struct io_uring_sqe *sqe)

{

	unsigned flags;

	int fd;

	bool fixed;



	flags = READ_ONCE(sqe->flags);

	fd = READ_ONCE(sqe->fd);



	if (!io_req_needs_file(req, fd))

		return 0;



	fixed = (flags & IOSQE_FIXED_FILE);

	if (unlikely(!fixed && req->needs_fixed_file))

		return -EBADF;



	return io_file_get(state, req, fd, &req->file, fixed);

}



static int io_grab_files(struct io_kiocb *req)

{

	int ret = -EBADF;
@@ -4858,7 +4872,7 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, 


	/* same numerical values with corresponding REQ_F_*, safe to copy */

	req->flags |= sqe_flags & (IOSQE_IO_DRAIN | IOSQE_IO_HARDLINK |

					IOSQE_ASYNC);

					IOSQE_ASYNC | IOSQE_FIXED_FILE);



	ret = io_req_set_file(state, req, sqe);

	if (unlikely(ret)) {