[AIO] handle signals when running sync iocbs

For pipe iocbs, we need to have the ability to have signals interrupt 
the execution of a sync iocb read/write.  Allow iocbs to signal to the 
sync iocb path that an interruptible sleep should be performed instead 
of the normal uninterruptible sleep.

Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com>
diff -purN --exclude=description 52_aio_down_reset_wakefn/fs/read_write.c 55_iocb_intr/fs/read_write.c
--- 52_aio_down_reset_wakefn/fs/read_write.c	2005-08-04 15:55:57.000000000 -0400
+++ 55_iocb_intr/fs/read_write.c	2005-08-08 17:15:42.000000000 -0400
@@ -205,11 +205,13 @@ Einval:
 
 static void wait_on_retry_sync_kiocb(struct kiocb *iocb)
 {
-	set_current_state(TASK_UNINTERRUPTIBLE);
+	set_current_state(kiocbIsIntr(iocb) ? TASK_INTERRUPTIBLE
+					    : TASK_UNINTERRUPTIBLE);
 	if (!kiocbIsKicked(iocb))
 		schedule();
 	else
 		kiocbClearKicked(iocb);
+	kiocbClearIntr(iocb);
 	__set_current_state(TASK_RUNNING);
 }
 
diff -purN --exclude=description 52_aio_down_reset_wakefn/include/linux/aio.h 55_iocb_intr/include/linux/aio.h
--- 52_aio_down_reset_wakefn/include/linux/aio.h	2005-08-08 17:15:41.000000000 -0400
+++ 55_iocb_intr/include/linux/aio.h	2005-08-08 17:15:42.000000000 -0400
@@ -27,6 +27,7 @@ struct kioctx;
 #define KIF_LOCKED		0
 #define KIF_KICKED		1
 #define KIF_CANCELLED		2
+#define KIF_INTR		3	/* use TASK_INTERRUPTIBLE waits */
 
 #define kiocbTryLock(iocb)	test_and_set_bit(KIF_LOCKED, &(iocb)->ki_flags)
 #define kiocbTryKick(iocb)	test_and_set_bit(KIF_KICKED, &(iocb)->ki_flags)
@@ -34,14 +35,17 @@ struct kioctx;
 #define kiocbSetLocked(iocb)	set_bit(KIF_LOCKED, &(iocb)->ki_flags)
 #define kiocbSetKicked(iocb)	set_bit(KIF_KICKED, &(iocb)->ki_flags)
 #define kiocbSetCancelled(iocb)	set_bit(KIF_CANCELLED, &(iocb)->ki_flags)
+#define kiocbSetIntr(iocb)	set_bit(KIF_INTR, &(iocb)->ki_flags)
 
 #define kiocbClearLocked(iocb)	clear_bit(KIF_LOCKED, &(iocb)->ki_flags)
 #define kiocbClearKicked(iocb)	clear_bit(KIF_KICKED, &(iocb)->ki_flags)
 #define kiocbClearCancelled(iocb)	clear_bit(KIF_CANCELLED, &(iocb)->ki_flags)
+#define kiocbClearIntr(iocb)	clear_bit(KIF_INTR, &(iocb)->ki_flags)
 
 #define kiocbIsLocked(iocb)	test_bit(KIF_LOCKED, &(iocb)->ki_flags)
 #define kiocbIsKicked(iocb)	test_bit(KIF_KICKED, &(iocb)->ki_flags)
 #define kiocbIsCancelled(iocb)	test_bit(KIF_CANCELLED, &(iocb)->ki_flags)
+#define kiocbIsIntr(iocb)	test_bit(KIF_INTR, &(iocb)->ki_flags)
 
 struct kiocb {
 	struct list_head	ki_run_list;