[PATCH 5/5] Make wait_on_retry_sync_kiocb killable

[Matthew Wilcox <matthew@wil.cx>]

Use TASK_KILLABLE to allow wait_on_retry_sync_kiocb to return -EINTR.
All callers then check the return value and break out of their loops.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
---
 fs/read_write.c |   17 ++++++++++++-----
 1 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/fs/read_write.c b/fs/read_write.c
index 124693e..3196a3b 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -218,14 +218,15 @@ Einval:
 	return -EINVAL;
 }
 
-static void wait_on_retry_sync_kiocb(struct kiocb *iocb)
+static int wait_on_retry_sync_kiocb(struct kiocb *iocb)
 {
-	set_current_state(TASK_UNINTERRUPTIBLE);
+	set_current_state(TASK_KILLABLE);
 	if (!kiocbIsKicked(iocb))
 		schedule();
 	else
 		kiocbClearKicked(iocb);
 	__set_current_state(TASK_RUNNING);
+	return fatal_signal_pending(current) ? -EINTR : 0;
 }
 
 ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
@@ -242,7 +243,9 @@ ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *pp
 		ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
 		if (ret != -EIOCBRETRY)
 			break;
-		wait_on_retry_sync_kiocb(&kiocb);
+		ret = wait_on_retry_sync_kiocb(&kiocb);
+		if (ret)
+			break;
 	}
 
 	if (-EIOCBQUEUED == ret)
@@ -300,7 +303,9 @@ ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, lof
 		ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
 		if (ret != -EIOCBRETRY)
 			break;
-		wait_on_retry_sync_kiocb(&kiocb);
+		ret = wait_on_retry_sync_kiocb(&kiocb);
+		if (ret)
+			break;
 	}
 
 	if (-EIOCBQUEUED == ret)
@@ -466,7 +471,9 @@ ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
 		ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos);
 		if (ret != -EIOCBRETRY)
 			break;
-		wait_on_retry_sync_kiocb(&kiocb);
+		ret = wait_on_retry_sync_kiocb(&kiocb);
+		if (ret)
+			break;
 	}
 
 	if (ret == -EIOCBQUEUED)
-- 
1.4.4.2