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: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2020-02-24 11:32:44 +03:00 committed by Jens Axboe
parent 444ebb5768
commit 8da11c1994

View File

@ -1253,6 +1253,15 @@ fallback:
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);
@ -4578,12 +4581,38 @@ static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
return table->files[index & IORING_FILE_TABLE_MASK];;
}
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;
struct file *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);
file = io_file_from_index(ctx, fd);
if (!file)
return -EBADF;
percpu_ref_get(&ctx->file_data->refs);
} else {
trace_io_uring_file_get(ctx, fd);
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)
{
struct io_ring_ctx *ctx = req->ctx;
unsigned flags;
int fd;
bool fixed;
flags = READ_ONCE(sqe->flags);
fd = READ_ONCE(sqe->fd);
@ -4591,26 +4620,11 @@ static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,
if (!io_req_needs_file(req, fd))
return 0;
if (flags & IOSQE_FIXED_FILE) {
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)
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))
return -EBADF;
}
fixed = (flags & IOSQE_FIXED_FILE);
if (unlikely(!fixed && req->needs_fixed_file))
return -EBADF;
return 0;
return io_file_get(state, req, fd, &req->file, fixed);
}
static int io_grab_files(struct io_kiocb *req)
@ -4857,8 +4871,8 @@ 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);
req->flags |= sqe_flags & (IOSQE_IO_DRAIN | IOSQE_IO_HARDLINK |
IOSQE_ASYNC | IOSQE_FIXED_FILE);
ret = io_req_set_file(state, req, sqe);
if (unlikely(ret)) {