---

yaml
---
r: 55934
b: refs/heads/master
c: 9c3060b
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: fdb902b1225e1668315f38e96d2f439452c03a15
+refs/heads/master: 9c3060bedd84144653a2ad7bea32389f65598d40

trunk/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>
@@ -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)
@@ -942,6 +946,14 @@ 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.
@@ -1526,8 +1538,7 @@ 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;
 	}
@@ -1551,6 +1562,19 @@ int fastcall io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 		fput(file);
 		return -EAGAIN;
 	}
+	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;
+		}
+	}
 
 	req->ki_filp = file;
 	ret = put_user(req->ki_key, &user_iocb->aio_key);

trunk/include/linux/aio.h

@@ -119,6 +119,12 @@ struct kiocb {
 
 	struct list_head	ki_list;	/* the aio core uses this
 						 * for cancellation */
+
+	/*
+	 * If the aio_resfd field of the userspace iocb is not zero,
+	 * this is the underlying file* to deliver event to.
+	 */
+	struct file		*ki_eventfd;
 };
 
 #define is_sync_kiocb(iocb)	((iocb)->ki_key == KIOCB_SYNC_KEY)

trunk/include/linux/aio_abi.h

@@ -45,6 +45,14 @@ enum {
 	IOCB_CMD_PWRITEV = 8,
 };
 
+/*
+ * Valid flags for the "aio_flags" member of the "struct iocb".
+ *
+ * IOCB_FLAG_RESFD - Set if the "aio_resfd" member of the "struct iocb"
+ *                   is valid.
+ */
+#define IOCB_FLAG_RESFD		(1 << 0)
+
 /* read() from /dev/aio returns these structures. */
 struct io_event {
 	__u64		data;		/* the data field from the iocb */
@@ -84,7 +92,15 @@ struct iocb {
 
 	/* extra parameters */
 	__u64	aio_reserved2;	/* TODO: use this for a (struct sigevent *) */
-	__u64	aio_reserved3;
+
+	/* flags for the "struct iocb" */
+	__u32	aio_flags;
+
+	/*
+	 * if the IOCB_FLAG_RESFD flag of "aio_flags" is set, this is an
+	 * eventfd to signal AIO readiness to
+	 */
+	__u32	aio_resfd;
 }; /* 64 bytes */
 
 #undef IFBIG