From: Pavel Begunkov <asml.silence@gmail.com> mainline inclusion from mainline-5.9-rc1 commit 9b0d911acce00b67f7e7336f838b732de7d917d6 category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA --------------------------- After pulling nxt from a request, it's no more a links head, so clear REQ_F_LINK_HEAD. Absence of this flag also indicates that there are no linked requests, so replacing REQ_F_LINK_NEXT, which can be killed. Linked timeouts also behave leaving the flag intact when necessary. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: yangerkun <yangerkun@huawei.com> Reviewed-by: zhangyi (F) <yi.zhang@huawei.com> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> --- fs/io_uring.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index b65669cc9850..36ea726a5c38 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -536,7 +536,6 @@ enum { REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT, REQ_F_LINK_HEAD_BIT, - REQ_F_LINK_NEXT_BIT, REQ_F_FAIL_LINK_BIT, REQ_F_INFLIGHT_BIT, REQ_F_CUR_POS_BIT, @@ -576,8 +575,6 @@ enum { /* head of a link */ REQ_F_LINK_HEAD = BIT(REQ_F_LINK_HEAD_BIT), - /* already grabbed next link */ - REQ_F_LINK_NEXT = BIT(REQ_F_LINK_NEXT_BIT), /* fail rest of links */ REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT), /* on inflight list */ @@ -1526,10 +1523,6 @@ static void io_req_link_next(struct io_kiocb *req, struct io_kiocb **nxtptr) struct io_ring_ctx *ctx = req->ctx; bool wake_ev = false; - /* Already got next link */ - if (req->flags & REQ_F_LINK_NEXT) - return; - /* * The list should never be empty when we are called here. But could * potentially happen if the chain is messed up, check to be on the @@ -1554,7 +1547,6 @@ static void io_req_link_next(struct io_kiocb *req, struct io_kiocb **nxtptr) break; } - req->flags |= REQ_F_LINK_NEXT; if (wake_ev) io_cqring_ev_posted(ctx); } @@ -1595,6 +1587,7 @@ static void io_req_find_next(struct io_kiocb *req, struct io_kiocb **nxt) { if (likely(!(req->flags & REQ_F_LINK_HEAD))) return; + req->flags &= ~REQ_F_LINK_HEAD; /* * If LINK is set, we have dependent requests in this chain. If we -- 2.25.1