On 11/17/21 10:47 AM, Yan, Zheng wrote:
On Wed, Nov 17, 2021 at 4:13 AM Jeff Layton <jlayton@xxxxxxxxxx> wrote:
On Tue, 2021-11-16 at 17:20 +0800, xiubli@xxxxxxxxxx wrote:
From: Xiubo Li <xiubli@xxxxxxxxxx>
In case truncating a file to a smaller sizeA, the sizeA will be kept
in truncate_size. And if truncate the file to a bigger sizeB, the
MDS will only increase the truncate_seq, but still using the sizeA as
the truncate_size.
Do you mean "kept in ci->i_truncate_size" ? If so, is this really the
correct fix? I'll note this in the sources:
u32 i_truncate_seq; /* last truncate to smaller size */
u64 i_truncate_size; /* and the size we last truncated down to */
Maybe the MDS ought not bump the truncate_seq unless it was truncating
to a smaller size? If not, then that comment seems wrong at least.
mds does not change truncate_{seq,size} when truncating file to bigger size
Yeah, right.
It was introduced by the fscrypt support related patch.
BRs
-- Xiubo
So when filling the inode it will truncate the pagecache by using
truncate_sizeA again, which makes no sense and will trim the inocent
pages.
Is there a reproducer for this? It would be nice to put something in
xfstests for it if so.
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
---
fs/ceph/inode.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 1b4ce453d397..b4f784684e64 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -738,10 +738,11 @@ int ceph_fill_file_size(struct inode *inode, int issued,
* don't hold those caps, then we need to check whether
* the file is either opened or mmaped
*/
- if ((issued & (CEPH_CAP_FILE_CACHE|
+ if (ci->i_truncate_size != truncate_size &&
+ ((issued & (CEPH_CAP_FILE_CACHE|
CEPH_CAP_FILE_BUFFER)) ||
mapping_mapped(inode->i_mapping) ||
- __ceph_is_file_opened(ci)) {
+ __ceph_is_file_opened(ci))) {
ci->i_truncate_pending++;
queue_trunc = 1;
}
--
Jeff Layton <jlayton@xxxxxxxxxx>
