Merge tag 'io_uring-5.12-2021-04-02' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:
 "Nothing really major in here, and finally nothing really related to
  signals. A few minor fixups related to the threading changes, and some
  general fixes, that's it.

  There's the pending gdb-get-confused-about-arch, but that's more of a
  cosmetic issue, nothing that hinder use of it. And given that other
  archs will likely be affected by that oddity too, better to postpone
  any changes there until 5.13 imho"

* tag 'io_uring-5.12-2021-04-02' of git://git.kernel.dk/linux-block:
  io_uring: move reissue into regular IO path
  io_uring: fix EIOCBQUEUED iter revert
  io_uring/io-wq: protect against sprintf overflow
  io_uring: don't mark S_ISBLK async work as unbounded
  io_uring: drop sqd lock before handling signals for SQPOLL
  io_uring: handle setup-failed ctx in kill_timeouts
  io_uring: always go for cancellation spin on exec

fs/io-wq.c

@@ -484,7 +484,7 @@ static int io_wqe_worker(void *data)
 	worker->flags |= (IO_WORKER_F_UP | IO_WORKER_F_RUNNING);
 	io_wqe_inc_running(worker);
 
-	sprintf(buf, "iou-wrk-%d", wq->task_pid);
+	snprintf(buf, sizeof(buf), "iou-wrk-%d", wq->task_pid);
 	set_task_comm(current, buf);
 
 	while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
@@ -711,7 +711,7 @@ static int io_wq_manager(void *data)
 	char buf[TASK_COMM_LEN];
 	int node;
 
-	sprintf(buf, "iou-mgr-%d", wq->task_pid);
+	snprintf(buf, sizeof(buf), "iou-mgr-%d", wq->task_pid);
 	set_task_comm(current, buf);
 
 	do {

fs/io_uring.c

@@ -697,6 +697,7 @@ enum {
 	REQ_F_NO_FILE_TABLE_BIT,
 	REQ_F_LTIMEOUT_ACTIVE_BIT,
 	REQ_F_COMPLETE_INLINE_BIT,
+	REQ_F_REISSUE_BIT,
 
 	/* not a real bit, just to check we're not overflowing the space */
 	__REQ_F_LAST_BIT,
@@ -740,6 +741,8 @@ enum {
 	REQ_F_LTIMEOUT_ACTIVE	= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT),
 	/* completion is deferred through io_comp_state */
 	REQ_F_COMPLETE_INLINE	= BIT(REQ_F_COMPLETE_INLINE_BIT),
+	/* caller should reissue async */
+	REQ_F_REISSUE		= BIT(REQ_F_REISSUE_BIT),
 };
 
 struct async_poll {
@@ -1213,7 +1216,7 @@ static void io_prep_async_work(struct io_kiocb *req)
 	if (req->flags & REQ_F_ISREG) {
 		if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
 			io_wq_hash_work(&req->work, file_inode(req->file));
-	} else {
+	} else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
 		if (def->unbound_nonreg_file)
 			req->work.flags |= IO_WQ_WORK_UNBOUND;
 	}
@@ -2503,8 +2506,10 @@ static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
 
 	if (req->rw.kiocb.ki_flags & IOCB_WRITE)
 		kiocb_end_write(req);
-	if ((res == -EAGAIN || res == -EOPNOTSUPP) && io_rw_reissue(req))
+	if ((res == -EAGAIN || res == -EOPNOTSUPP) && io_rw_should_reissue(req)) {
+		req->flags |= REQ_F_REISSUE;
 		return;
+	}
 	if (res != req->result)
 		req_set_fail_links(req);
 	if (req->flags & REQ_F_BUFFER_SELECTED)
@@ -3283,11 +3288,7 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
 
 	ret = io_iter_do_read(req, iter);
 
-	if (ret == -EIOCBQUEUED) {
-		if (req->async_data)
-			iov_iter_revert(iter, io_size - iov_iter_count(iter));
-		goto out_free;
-	} else if (ret == -EAGAIN) {
+	if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
 		/* IOPOLL retry should happen for io-wq threads */
 		if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
 			goto done;
@@ -3297,6 +3298,8 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
 		/* some cases will consume bytes even on error returns */
 		iov_iter_revert(iter, io_size - iov_iter_count(iter));
 		ret = 0;
+	} else if (ret == -EIOCBQUEUED) {
+		goto out_free;
 	} else if (ret <= 0 || ret == io_size || !force_nonblock ||
 		   (req->flags & REQ_F_NOWAIT) || !(req->flags & REQ_F_ISREG)) {
 		/* read all, failed, already did sync or don't want to retry */
@@ -3409,6 +3412,9 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
 	else
 		ret2 = -EINVAL;
 
+	if (req->flags & REQ_F_REISSUE)
+		ret2 = -EAGAIN;
+
 	/*
 	 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
 	 * retry them without IOCB_NOWAIT.
@@ -3418,8 +3424,6 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
 	/* no retry on NONBLOCK nor RWF_NOWAIT */
 	if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
 		goto done;
-	if (ret2 == -EIOCBQUEUED && req->async_data)
-		iov_iter_revert(iter, io_size - iov_iter_count(iter));
 	if (!force_nonblock || ret2 != -EAGAIN) {
 		/* IOPOLL retry should happen for io-wq threads */
 		if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
@@ -6164,6 +6168,7 @@ static void io_wq_submit_work(struct io_wq_work *work)
 		ret = -ECANCELED;
 
 	if (!ret) {
+		req->flags &= ~REQ_F_REISSUE;
 		do {
 			ret = io_issue_sqe(req, 0);
 			/*
@@ -6718,7 +6723,7 @@ static int io_sq_thread(void *data)
 	char buf[TASK_COMM_LEN];
 	DEFINE_WAIT(wait);
 
-	sprintf(buf, "iou-sqp-%d", sqd->task_pid);
+	snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
 	set_task_comm(current, buf);
 	current->pf_io_worker = NULL;
 
@@ -6733,22 +6738,25 @@ static int io_sq_thread(void *data)
 		int ret;
 		bool cap_entries, sqt_spin, needs_sched;
 
-		if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state)) {
+		if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
+		    signal_pending(current)) {
+			bool did_sig = false;
+
 			mutex_unlock(&sqd->lock);
+			if (signal_pending(current)) {
+				struct ksignal ksig;
+
+				did_sig = get_signal(&ksig);
+			}
 			cond_resched();
 			mutex_lock(&sqd->lock);
+			if (did_sig)
+				break;
 			io_run_task_work();
 			io_run_task_work_head(&sqd->park_task_work);
 			timeout = jiffies + sqd->sq_thread_idle;
 			continue;
 		}
-		if (signal_pending(current)) {
-			struct ksignal ksig;
-
-			if (!get_signal(&ksig))
-				continue;
-			break;
-		}
 		sqt_spin = false;
 		cap_entries = !list_is_singular(&sqd->ctx_list);
 		list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
@@ -8603,9 +8611,9 @@ static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
 			canceled++;
 		}
 	}
+	if (canceled != 0)
 		io_commit_cqring(ctx);
 	spin_unlock_irq(&ctx->completion_lock);
-
 	if (canceled != 0)
 		io_cqring_ev_posted(ctx);
 	return canceled != 0;
@@ -9002,6 +9010,8 @@ void __io_uring_task_cancel(void)
 
 	/* make sure overflow events are dropped */
 	atomic_inc(&tctx->in_idle);
+	__io_uring_files_cancel(NULL);
+
 	do {
 		/* read completions before cancelations */
 		inflight = tctx_inflight(tctx);