Commit 353fb07e authored Sep 30, 2005 by Zach Brown Committed by Linus Torvalds Sep 30, 2005

[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>

parent 897f15fb

fs/aio.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1347,7 +1347,7 @@ static ssize_t aio_pread(struct kiocb *iocb)
		* 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 @@ static ssize_t aio_pwrite(struct kiocb *iocb)
		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;