>From a7332719d80dc94c11d1c1cb32c88b7f25e1ae61 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 24 Nov 2015 14:19:22 +0100 Subject: [PATCH] aio: Fix freeze protection of aio writes Currently we dropped freeze protection of aio writes just after IO was submitted. Thus aio write could be in flight while the filesystem was frozen and that could result in unexpected situation like aio completion wanting to convert extent type on frozen filesystem. Testcase from Dmitry triggering this is like: for ((i=0;i<60;i++));do fsfreeze -f /mnt ;sleep 1;fsfreeze -u /mnt;done & fio --bs=4k --ioengine=libaio --iodepth=128 --size=1g --direct=1 \ --runtime=60 --filename=/mnt/file --name=rand-write --rw=randwrite Fix the problem by dropping freeze protection only once IO is completed in aio_complete(). Reported-by: Dmitry Monakhov Signed-off-by: Jan Kara --- fs/aio.c | 10 +++++++--- include/linux/fs.h | 1 + 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index 155f84253f33..3775030053f7 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1065,6 +1065,9 @@ static void aio_complete(struct kiocb *kiocb, long res, long res2) unsigned tail, pos, head; unsigned long flags; + if (kiocb->ki_flags & IOCB_WRITE) + file_end_write(kiocb->ki_filp); + /* * Special case handling for sync iocbs: * - events go directly into the iocb for fast handling @@ -1449,13 +1452,14 @@ rw_common: len = ret; - if (rw == WRITE) + /* We drop freeze protection in aio_complete() */ + if (rw == WRITE) { file_start_write(file); + req->ki_flags |= IOCB_WRITE; + } ret = iter_op(req, &iter); - if (rw == WRITE) - file_end_write(file); kfree(iovec); break; diff --git a/include/linux/fs.h b/include/linux/fs.h index 3aa514254161..54af40ed6a26 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -319,6 +319,7 @@ struct writeback_control; #define IOCB_EVENTFD (1 << 0) #define IOCB_APPEND (1 << 1) #define IOCB_DIRECT (1 << 2) +#define IOCB_WRITE (1 << 3) struct kiocb { struct file *ki_filp; -- 2.1.4