X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Faio.c;h=9dec7d2d546e0e12e200898993f1b272111f5cee;hb=f6135d12db4bed3b992052020f1c50d749cd8dc6;hp=ac1c1587aa02dad4583b7a394cf1261e79a0c680;hpb=a9deecba19b8f384d97f82c75379da48bccb2588;p=linux-2.6-omap-h63xx.git

diff --git a/fs/aio.c b/fs/aio.c
index ac1c1587aa0..9dec7d2d546 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -30,6 +30,7 @@
 #include <linux/highmem.h>
 #include <linux/workqueue.h>
 #include <linux/security.h>
+#include <linux/eventfd.h>
 
 #include <asm/kmap_types.h>
 #include <asm/uaccess.h>
@@ -302,7 +303,7 @@ static void wait_for_all_aios(struct kioctx *ctx)
 	set_task_state(tsk, TASK_UNINTERRUPTIBLE);
 	while (ctx->reqs_active) {
 		spin_unlock_irq(&ctx->ctx_lock);
-		schedule();
+		io_schedule();
 		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
 		spin_lock_irq(&ctx->ctx_lock);
 	}
@@ -322,7 +323,7 @@ ssize_t fastcall wait_on_sync_kiocb(struct kiocb *iocb)
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		if (!iocb->ki_users)
 			break;
-		schedule();
+		io_schedule();
 	}
 	__set_current_state(TASK_RUNNING);
 	return iocb->ki_user_data;
@@ -417,6 +418,7 @@ static struct kiocb fastcall *__aio_get_req(struct kioctx *ctx)
 	req->private = NULL;
 	req->ki_iovec = NULL;
 	INIT_LIST_HEAD(&req->ki_run_list);
+	req->ki_eventfd = ERR_PTR(-EINVAL);
 
 	/* Check if the completion queue has enough free space to
 	 * accept an event from this io.
@@ -458,6 +460,8 @@ static inline void really_put_req(struct kioctx *ctx, struct kiocb *req)
 {
 	assert_spin_locked(&ctx->ctx_lock);
 
+	if (!IS_ERR(req->ki_eventfd))
+		fput(req->ki_eventfd);
 	if (req->ki_dtor)
 		req->ki_dtor(req);
 	if (req->ki_iovec != &req->ki_inline_vec)
@@ -706,18 +710,9 @@ static ssize_t aio_run_iocb(struct kiocb *iocb)
 
 	/*
 	 * Now we are all set to call the retry method in async
-	 * context. By setting this thread's io_wait context
-	 * to point to the wait queue entry inside the currently
-	 * running iocb for the duration of the retry, we ensure
-	 * that async notification wakeups are queued by the
-	 * operation instead of blocking waits, and when notified,
-	 * cause the iocb to be kicked for continuation (through
-	 * the aio_wake_function callback).
+	 * context.
 	 */
-	BUG_ON(current->io_wait != NULL);
-	current->io_wait = &iocb->ki_wait;
 	ret = retry(iocb);
-	current->io_wait = NULL;
 
 	if (ret != -EIOCBRETRY && ret != -EIOCBQUEUED) {
 		BUG_ON(!list_empty(&iocb->ki_wait.task_list));
@@ -942,6 +937,14 @@ int fastcall aio_complete(struct kiocb *iocb, long res, long res2)
 		return 1;
 	}
 
+	/*
+	 * Check if the user asked us to deliver the result through an
+	 * eventfd. The eventfd_signal() function is safe to be called
+	 * from IRQ context.
+	 */
+	if (!IS_ERR(iocb->ki_eventfd))
+		eventfd_signal(iocb->ki_eventfd, 1);
+
 	info = &ctx->ring_info;
 
 	/* add a completion event to the ring buffer.
@@ -1158,7 +1161,12 @@ retry:
 			ret = 0;
 			if (to.timed_out)	/* Only check after read evt */
 				break;
-			schedule();
+			/* Try to only show up in io wait if there are ops
+			 *  in flight */
+			if (ctx->reqs_active)
+				io_schedule();
+			else
+				schedule();
 			if (signal_pending(tsk)) {
 				ret = -EINTR;
 				break;
@@ -1496,10 +1504,7 @@ static ssize_t aio_setup_iocb(struct kiocb *kiocb)
  * 	Simply triggers a retry of the operation via kick_iocb.
  *
  * 	This callback is specified in the wait queue entry in
- *	a kiocb	(current->io_wait points to this wait queue
- *	entry when an aio operation executes; it is used
- * 	instead of a synchronous wait when an i/o blocking
- *	condition is encountered during aio).
+ *	a kiocb.
  *
  * Note:
  * This routine is executed with the wait queue lock held.
@@ -1526,8 +1531,7 @@ int fastcall io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 	ssize_t ret;
 
 	/* enforce forwards compatibility on users */
-	if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2 ||
-		     iocb->aio_reserved3)) {
+	if (unlikely(iocb->aio_reserved1 || iocb->aio_reserved2)) {
 		pr_debug("EINVAL: io_submit: reserve field set\n");
 		return -EINVAL;
 	}
@@ -1551,8 +1555,21 @@ int fastcall io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 		fput(file);
 		return -EAGAIN;
 	}
-
 	req->ki_filp = file;
+	if (iocb->aio_flags & IOCB_FLAG_RESFD) {
+		/*
+		 * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an
+		 * instance of the file* now. The file descriptor must be
+		 * an eventfd() fd, and will be signaled for each completed
+		 * event using the eventfd_signal() function.
+		 */
+		req->ki_eventfd = eventfd_fget((int) iocb->aio_resfd);
+		if (unlikely(IS_ERR(req->ki_eventfd))) {
+			ret = PTR_ERR(req->ki_eventfd);
+			goto out_put_req;
+		}
+	}
+
 	ret = put_user(req->ki_key, &user_iocb->aio_key);
 	if (unlikely(ret)) {
 		dprintk("EFAULT: aio_key\n");