Commit f9bd67f6 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: only !null ptr to io_issue_sqe() 



Pass only non-null @nxt to io_issue_sqe() and handle it at the caller's
side. And propagate it.

- kiocb_done() is only called from io_read() and io_write(), which are
only called from io_issue_sqe(), so it's @nxt != NULL

- io_put_req_find_next() is called either with explicitly non-null local
nxt, or from one of the functions in io_issue_sqe() switch (or their
callees).

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent b18fdf71

fs/io_uring.c

+12 −16
Original line number Diff line number Diff line
@@ -990,21 +990,13 @@ static void io_free_req(struct io_kiocb *req) 
 * Drop reference to request, return next in chain (if there is one) if this

 * was the last reference to this request.

 */

__attribute__((nonnull))

static void io_put_req_find_next(struct io_kiocb *req, struct io_kiocb **nxtptr)

{

	struct io_kiocb *nxt = NULL;



	io_req_find_next(req, &nxt);

	io_req_find_next(req, nxtptr);



	if (refcount_dec_and_test(&req->refs))

		__io_free_req(req);



	if (nxt) {

		if (nxtptr)

			*nxtptr = nxt;

		else

			io_queue_async_work(nxt);

	}

}



static void io_put_req(struct io_kiocb *req)
@@ -1488,7 +1480,7 @@ static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret) 
static void kiocb_done(struct kiocb *kiocb, ssize_t ret, struct io_kiocb **nxt,

		       bool in_async)

{

	if (in_async && ret >= 0 && nxt && kiocb->ki_complete == io_complete_rw)

	if (in_async && ret >= 0 && kiocb->ki_complete == io_complete_rw)

		*nxt = __io_complete_rw(kiocb, ret);

	else

		io_rw_done(kiocb, ret);
@@ -2585,6 +2577,7 @@ static int io_req_defer(struct io_kiocb *req) 
	return -EIOCBQUEUED;

}



__attribute__((nonnull))

static int io_issue_sqe(struct io_kiocb *req, struct io_kiocb **nxt,

			bool force_nonblock)

{
@@ -2901,10 +2894,13 @@ static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) 


static void __io_queue_sqe(struct io_kiocb *req)

{

	struct io_kiocb *nxt = io_prep_linked_timeout(req);

	struct io_kiocb *linked_timeout = io_prep_linked_timeout(req);

	struct io_kiocb *nxt = NULL;

	int ret;



	ret = io_issue_sqe(req, NULL, true);

	ret = io_issue_sqe(req, &nxt, true);

	if (nxt)

		io_queue_async_work(nxt);



	/*

	 * We async punt it if the file wasn't marked NOWAIT, or if the file
@@ -2940,11 +2936,11 @@ err: 
	/* drop submission reference */

	io_put_req(req);



	if (nxt) {

	if (linked_timeout) {

		if (!ret)

			io_queue_linked_timeout(nxt);

			io_queue_linked_timeout(linked_timeout);

		else

			io_put_req(nxt);

			io_put_req(linked_timeout);

	}



	/* and drop final reference, if we failed */

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