[PATCH] aio: avoid extra aio_{read,write} call when ki_left == 0
Recently aio_p{read,write} changed to perform retries internally rather
than returning -EIOCBRETRY. This inadvertantly resulted in always calling
aio_{read,write} with ki_left at 0 which would in turn immediately return
0. Harmless, but we can avoid this call by checking in the caller.
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/aio.c b/fs/aio.c
index 9edc0e4..d6b1551 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1347,7 +1347,7 @@
* regular files we retry till we complete the entire read or
* find that we can't read any more data (e.g short reads).
*/
- } while (ret > 0 &&
+ } while (ret > 0 && iocb->ki_left > 0 &&
!S_ISFIFO(inode->i_mode) && !S_ISSOCK(inode->i_mode));
/* This means we must have transferred all that we could */
@@ -1371,7 +1371,7 @@
iocb->ki_buf += ret;
iocb->ki_left -= ret;
}
- } while (ret > 0);
+ } while (ret > 0 && iocb->ki_left > 0);
if ((ret == 0) || (iocb->ki_left == 0))
ret = iocb->ki_nbytes - iocb->ki_left;