Commit c5e9f6a9 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: unify getting ctx from passed in file descriptor 



io_uring_enter() and io_uring_register() end up having duplicated code
for getting a ctx from a passed in file descriptor, for either a
registered ring descriptor or a normal file descriptor. Move the
io_uring_register_get_file() into io_uring.c and name it a bit more
generically, and use it from both callsites rather than have that logic
and handling duplicated.

Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent b4d893d6

io_uring/bpf-ops.c

+1 −1
Original line number Diff line number Diff line
@@ -181,7 +181,7 @@ static int bpf_io_reg(void *kdata, struct bpf_link *link) 
	struct file *file;

	int ret = -EBUSY;



	file = io_uring_register_get_file(ops->ring_fd, false);

	file = io_uring_ctx_get_file(ops->ring_fd, false);

	if (IS_ERR(file))

		return PTR_ERR(file);

	ctx = file->private_data;

io_uring/io_uring.c

+36 −21
Original line number Diff line number Diff line
@@ -2543,39 +2543,54 @@ static int io_get_ext_arg(struct io_ring_ctx *ctx, unsigned flags, 
#endif

}



SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,

		u32, min_complete, u32, flags, const void __user *, argp,

		size_t, argsz)

/*

 * Given an 'fd' value, return the ctx associated with if. If 'registered' is

 * true, then the registered index is used. Otherwise, the normal fd table.

 * Caller must call fput() on the returned file if it isn't a registered file,

 * unless it's an ERR_PTR.

 */

struct file *io_uring_ctx_get_file(unsigned int fd, bool registered)

{

	struct io_ring_ctx *ctx;

	struct file *file;

	long ret;



	if (unlikely(flags & ~IORING_ENTER_FLAGS))

		return -EINVAL;



	if (registered) {

		/*

		 * Ring fd has been registered via IORING_REGISTER_RING_FDS, we

		 * need only dereference our task private array to find it.

		 */

	if (flags & IORING_ENTER_REGISTERED_RING) {

		struct io_uring_task *tctx = current->io_uring;



		if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX))

			return -EINVAL;

			return ERR_PTR(-EINVAL);

		fd = array_index_nospec(fd, IO_RINGFD_REG_MAX);

		file = tctx->registered_rings[fd];

		if (unlikely(!file))

			return -EBADF;

	} else {

		file = fget(fd);

	}



	if (unlikely(!file))

			return -EBADF;

		ret = -EOPNOTSUPP;

		if (unlikely(!io_is_uring_fops(file)))

			goto out;

		return ERR_PTR(-EBADF);

	if (io_is_uring_fops(file))

		return file;

	fput(file);

	return ERR_PTR(-EOPNOTSUPP);

}





SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,

		u32, min_complete, u32, flags, const void __user *, argp,

		size_t, argsz)

{

	struct io_ring_ctx *ctx;

	struct file *file;

	long ret;



	if (unlikely(flags & ~IORING_ENTER_FLAGS))

		return -EINVAL;



	file = io_uring_ctx_get_file(fd, flags & IORING_ENTER_REGISTERED_RING);

	if (IS_ERR(file))

		return PTR_ERR(file);

	ctx = file->private_data;

	ret = -EBADFD;

	/*

io_uring/io_uring.h

+1 −0
Original line number Diff line number Diff line
@@ -173,6 +173,7 @@ void io_req_track_inflight(struct io_kiocb *req); 
struct file *io_file_get_normal(struct io_kiocb *req, int fd);

struct file *io_file_get_fixed(struct io_kiocb *req, int fd,

			       unsigned issue_flags);

struct file *io_uring_ctx_get_file(unsigned int fd, bool registered);



void io_req_task_queue(struct io_kiocb *req);

void io_req_task_complete(struct io_tw_req tw_req, io_tw_token_t tw);

io_uring/register.c

+1 −34
Original line number Diff line number Diff line
@@ -938,39 +938,6 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, 
	return ret;

}



/*

 * Given an 'fd' value, return the ctx associated with if. If 'registered' is

 * true, then the registered index is used. Otherwise, the normal fd table.

 * Caller must call fput() on the returned file if it isn't a registered file,

 * unless it's an ERR_PTR.

 */

struct file *io_uring_register_get_file(unsigned int fd, bool registered)

{

	struct file *file;



	if (registered) {

		/*

		 * Ring fd has been registered via IORING_REGISTER_RING_FDS, we

		 * need only dereference our task private array to find it.

		 */

		struct io_uring_task *tctx = current->io_uring;



		if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX))

			return ERR_PTR(-EINVAL);

		fd = array_index_nospec(fd, IO_RINGFD_REG_MAX);

		file = tctx->registered_rings[fd];

	} else {

		file = fget(fd);

	}



	if (unlikely(!file))

		return ERR_PTR(-EBADF);

	if (io_is_uring_fops(file))

		return file;

	fput(file);

	return ERR_PTR(-EOPNOTSUPP);

}



static int io_uring_register_send_msg_ring(void __user *arg, unsigned int nr_args)

{

	struct io_uring_sqe sqe;
@@ -1025,7 +992,7 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, 
	if (fd == -1)

		return io_uring_register_blind(opcode, arg, nr_args);



	file = io_uring_register_get_file(fd, use_registered_ring);

	file = io_uring_ctx_get_file(fd, use_registered_ring);

	if (IS_ERR(file))

		return PTR_ERR(file);

	ctx = file->private_data;

io_uring/register.h

+0 −1
Original line number Diff line number Diff line
@@ -4,6 +4,5 @@ 


int io_eventfd_unregister(struct io_ring_ctx *ctx);

int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id);

struct file *io_uring_register_get_file(unsigned int fd, bool registered);



#endif