diff options
Diffstat (limited to 'io_uring/io_uring.c')
| -rw-r--r-- | io_uring/io_uring.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index ac8c488e3077..4a1e482747cc 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -176,6 +176,11 @@ static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx) return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head); } +static inline unsigned int __io_cqring_events_user(struct io_ring_ctx *ctx) +{ + return READ_ONCE(ctx->rings->cq.tail) - READ_ONCE(ctx->rings->cq.head); +} + static bool io_match_linked(struct io_kiocb *head) { struct io_kiocb *req; @@ -2315,7 +2320,7 @@ static inline bool io_has_work(struct io_ring_ctx *ctx) static inline bool io_should_wake(struct io_wait_queue *iowq) { struct io_ring_ctx *ctx = iowq->ctx; - int dist = ctx->cached_cq_tail - (int) iowq->cq_tail; + int dist = READ_ONCE(ctx->rings->cq.tail) - (int) iowq->cq_tail; /* * Wake up if we have enough events, or if a timeout occurred since we @@ -2399,7 +2404,8 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, return ret; io_cqring_overflow_flush(ctx); - if (io_cqring_events(ctx) >= min_events) + /* if user messes with these they will just get an early return */ + if (__io_cqring_events_user(ctx) >= min_events) return 0; } while (ret > 0); |