Commit 0f078896 authored by Jens Axboe's avatar Jens Axboe
Browse files

Merge branch 'io_uring-5.9' into for-5.10/io_uring 

* io_uring-5.9:
  io_uring: fix async buffered reads when readahead is disabled
  io_uring: fix potential ABBA deadlock in ->show_fdinfo()
  io_uring: always delete double poll wait entry on match
parents fb0155a0 c8d317aa

fs/io_uring.c

+18 −5
Original line number Diff line number Diff line
@@ -3049,6 +3049,7 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode, 
	if (!wake_page_match(wpq, key))

		return 0;



	req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;

	list_del_init(&wait->entry);



	init_task_work(&req->task_work, io_req_task_submit);
@@ -3106,6 +3107,7 @@ static bool io_rw_should_retry(struct io_kiocb *req) 
	wait->wait.flags = 0;

	INIT_LIST_HEAD(&wait->wait.entry);

	kiocb->ki_flags |= IOCB_WAITQ;

	kiocb->ki_flags &= ~IOCB_NOWAIT;

	kiocb->ki_waitq = wait;



	io_get_req_task(req);
@@ -4743,6 +4745,8 @@ static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode, 
	if (mask && !(mask & poll->events))

		return 0;



	list_del_init(&wait->entry);



	if (poll && poll->head) {

		bool done;
@@ -8412,11 +8416,19 @@ static int io_uring_show_cred(int id, void *p, void *data) 


static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)

{

	bool has_lock;

	int i;



	mutex_lock(&ctx->uring_lock);

	/*

	 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,

	 * since fdinfo case grabs it in the opposite direction of normal use

	 * cases. If we fail to get the lock, we just don't iterate any

	 * structures that could be going away outside the io_uring mutex.

	 */

	has_lock = mutex_trylock(&ctx->uring_lock);



	seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);

	for (i = 0; i < ctx->nr_user_files; i++) {

	for (i = 0; has_lock && i < ctx->nr_user_files; i++) {

		struct fixed_file_table *table;

		struct file *f;
@@ -8428,13 +8440,13 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) 
			seq_printf(m, "%5u: <none>\n", i);

	}

	seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);

	for (i = 0; i < ctx->nr_user_bufs; i++) {

	for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {

		struct io_mapped_ubuf *buf = &ctx->user_bufs[i];



		seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf,

						(unsigned int) buf->len);

	}

	if (!idr_is_empty(&ctx->personality_idr)) {

	if (has_lock && !idr_is_empty(&ctx->personality_idr)) {

		seq_printf(m, "Personalities:\n");

		idr_for_each(&ctx->personality_idr, io_uring_show_cred, m);

	}
@@ -8449,6 +8461,7 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) 
					req->task->task_works != NULL);

	}

	spin_unlock_irq(&ctx->completion_lock);

	if (has_lock)

		mutex_unlock(&ctx->uring_lock);

}

mm/filemap.c

+5 −1
Original line number Diff line number Diff line
@@ -2365,7 +2365,11 @@ ssize_t generic_file_buffered_read(struct kiocb *iocb, 
		}



		if (!PageUptodate(page)) {

			if (iocb->ki_flags & IOCB_WAITQ)

				error = lock_page_async(page, iocb->ki_waitq);

			else

				error = lock_page_killable(page);



			if (unlikely(error))

				goto readpage_error;

			if (!PageUptodate(page)) {