tools headers UAPI: Sync linux/prctl.h with the kernel sources
[linux-2.6-microblaze.git] / fs / io_uring.c
index c07913e..1f68105 100644 (file)
@@ -1026,6 +1026,7 @@ static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
                             const struct iovec *fast_iov,
                             struct iov_iter *iter, bool force);
 static void io_req_drop_files(struct io_kiocb *req);
+static void io_req_task_queue(struct io_kiocb *req);
 
 static struct kmem_cache *req_cachep;
 
@@ -1069,8 +1070,12 @@ static bool io_match_task(struct io_kiocb *head,
 {
        struct io_kiocb *req;
 
-       if (task && head->task != task)
+       if (task && head->task != task) {
+               /* in terms of cancelation, always match if req task is dead */
+               if (head->task->flags & PF_EXITING)
+                       return true;
                return false;
+       }
        if (!files)
                return true;
 
@@ -1630,18 +1635,11 @@ static void __io_queue_deferred(struct io_ring_ctx *ctx)
        do {
                struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
                                                struct io_defer_entry, list);
-               struct io_kiocb *link;
 
                if (req_need_defer(de->req, de->seq))
                        break;
                list_del_init(&de->list);
-               /* punt-init is done before queueing for defer */
-               link = __io_queue_async_work(de->req);
-               if (link) {
-                       __io_queue_linked_timeout(link);
-                       /* drop submission reference */
-                       io_put_req_deferred(link, 1);
-               }
+               io_req_task_queue(de->req);
                kfree(de);
        } while (!list_empty(&ctx->defer_list));
 }
@@ -1775,12 +1773,13 @@ static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
        struct io_kiocb *req, *tmp;
        struct io_uring_cqe *cqe;
        unsigned long flags;
-       bool all_flushed;
+       bool all_flushed, posted;
        LIST_HEAD(list);
 
        if (!force && __io_cqring_events(ctx) == rings->cq_ring_entries)
                return false;
 
+       posted = false;
        spin_lock_irqsave(&ctx->completion_lock, flags);
        list_for_each_entry_safe(req, tmp, &ctx->cq_overflow_list, compl.list) {
                if (!io_match_task(req, tsk, files))
@@ -1800,6 +1799,7 @@ static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
                        WRITE_ONCE(ctx->rings->cq_overflow,
                                   ctx->cached_cq_overflow);
                }
+               posted = true;
        }
 
        all_flushed = list_empty(&ctx->cq_overflow_list);
@@ -1809,9 +1809,11 @@ static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
                ctx->rings->sq_flags &= ~IORING_SQ_CQ_OVERFLOW;
        }
 
-       io_commit_cqring(ctx);
+       if (posted)
+               io_commit_cqring(ctx);
        spin_unlock_irqrestore(&ctx->completion_lock, flags);
-       io_cqring_ev_posted(ctx);
+       if (posted)
+               io_cqring_ev_posted(ctx);
 
        while (!list_empty(&list)) {
                req = list_first_entry(&list, struct io_kiocb, compl.list);
@@ -2203,6 +2205,9 @@ static void __io_req_task_submit(struct io_kiocb *req)
        else
                __io_req_task_cancel(req, -EFAULT);
        mutex_unlock(&ctx->uring_lock);
+
+       if (ctx->flags & IORING_SETUP_SQPOLL)
+               io_sq_thread_drop_mm_files();
 }
 
 static void io_req_task_submit(struct callback_head *cb)
@@ -6458,7 +6463,8 @@ static struct file *io_file_get(struct io_submit_state *state,
                file = __io_file_get(state, fd);
        }
 
-       if (file && file->f_op == &io_uring_fops) {
+       if (file && file->f_op == &io_uring_fops &&
+           !(req->flags & REQ_F_INFLIGHT)) {
                io_req_init_async(req);
                req->flags |= REQ_F_INFLIGHT;
 
@@ -7266,14 +7272,18 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
                                                TASK_INTERRUPTIBLE);
                /* make sure we run task_work before checking for signals */
                ret = io_run_task_work_sig();
-               if (ret > 0)
+               if (ret > 0) {
+                       finish_wait(&ctx->wait, &iowq.wq);
                        continue;
+               }
                else if (ret < 0)
                        break;
                if (io_should_wake(&iowq))
                        break;
-               if (test_bit(0, &ctx->cq_check_overflow))
+               if (test_bit(0, &ctx->cq_check_overflow)) {
+                       finish_wait(&ctx->wait, &iowq.wq);
                        continue;
+               }
                if (uts) {
                        timeout = schedule_timeout(timeout);
                        if (timeout == 0) {
@@ -8865,30 +8875,31 @@ static void io_cancel_defer_files(struct io_ring_ctx *ctx,
        }
 }
 
+static int io_uring_count_inflight(struct io_ring_ctx *ctx,
+                                  struct task_struct *task,
+                                  struct files_struct *files)
+{
+       struct io_kiocb *req;
+       int cnt = 0;
+
+       spin_lock_irq(&ctx->inflight_lock);
+       list_for_each_entry(req, &ctx->inflight_list, inflight_entry)
+               cnt += io_match_task(req, task, files);
+       spin_unlock_irq(&ctx->inflight_lock);
+       return cnt;
+}
+
 static void io_uring_cancel_files(struct io_ring_ctx *ctx,
                                  struct task_struct *task,
                                  struct files_struct *files)
 {
        while (!list_empty_careful(&ctx->inflight_list)) {
                struct io_task_cancel cancel = { .task = task, .files = files };
-               struct io_kiocb *req;
                DEFINE_WAIT(wait);
-               bool found = false;
+               int inflight;
 
-               spin_lock_irq(&ctx->inflight_lock);
-               list_for_each_entry(req, &ctx->inflight_list, inflight_entry) {
-                       if (!io_match_task(req, task, files))
-                               continue;
-                       found = true;
-                       break;
-               }
-               if (found)
-                       prepare_to_wait(&task->io_uring->wait, &wait,
-                                       TASK_UNINTERRUPTIBLE);
-               spin_unlock_irq(&ctx->inflight_lock);
-
-               /* We need to keep going until we don't find a matching req */
-               if (!found)
+               inflight = io_uring_count_inflight(ctx, task, files);
+               if (!inflight)
                        break;
 
                io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, &cancel, true);
@@ -8897,7 +8908,11 @@ static void io_uring_cancel_files(struct io_ring_ctx *ctx,
                io_cqring_overflow_flush(ctx, true, task, files);
                /* cancellations _may_ trigger task work */
                io_run_task_work();
-               schedule();
+
+               prepare_to_wait(&task->io_uring->wait, &wait,
+                               TASK_UNINTERRUPTIBLE);
+               if (inflight == io_uring_count_inflight(ctx, task, files))
+                       schedule();
                finish_wait(&task->io_uring->wait, &wait);
        }
 }
@@ -8955,8 +8970,6 @@ static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
        struct task_struct *task = current;
 
        if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
-               /* for SQPOLL only sqo_task has task notes */
-               WARN_ON_ONCE(ctx->sqo_task != current);
                io_disable_sqo_submit(ctx);
                task = ctx->sq_data->thread;
                atomic_inc(&task->io_uring->in_idle);
@@ -8966,19 +8979,12 @@ static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
        io_cancel_defer_files(ctx, task, files);
        io_cqring_overflow_flush(ctx, true, task, files);
 
+       io_uring_cancel_files(ctx, task, files);
        if (!files)
                __io_uring_cancel_task_requests(ctx, task);
-       else
-               io_uring_cancel_files(ctx, task, files);
 
        if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
                atomic_dec(&task->io_uring->in_idle);
-               /*
-                * If the files that are going away are the ones in the thread
-                * identity, clear them out.
-                */
-               if (task->io_uring->identity->files == files)
-                       task->io_uring->identity->files = NULL;
                io_sq_thread_unpark(ctx->sq_data);
        }
 }
@@ -9116,16 +9122,15 @@ void __io_uring_task_cancel(void)
                prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
 
                /*
-                * If we've seen completions, retry. This avoids a race where
-                * a completion comes in before we did prepare_to_wait().
+                * If we've seen completions, retry without waiting. This
+                * avoids a race where a completion comes in before we did
+                * prepare_to_wait().
                 */
-               if (inflight != tctx_inflight(tctx))
-                       continue;
-               schedule();
+               if (inflight == tctx_inflight(tctx))
+                       schedule();
                finish_wait(&tctx->wait, &wait);
        } while (1);
 
-       finish_wait(&tctx->wait, &wait);
        atomic_dec(&tctx->in_idle);
 
        io_uring_remove_task_files(tctx);
@@ -9136,6 +9141,9 @@ static int io_uring_flush(struct file *file, void *data)
        struct io_uring_task *tctx = current->io_uring;
        struct io_ring_ctx *ctx = file->private_data;
 
+       if (fatal_signal_pending(current) || (current->flags & PF_EXITING))
+               io_uring_cancel_task_requests(ctx, NULL);
+
        if (!tctx)
                return 0;