[PATCH 5.1 293/371] ceph: fix end offset in truncate_inode_pages_range call

From: Greg Kroah-Hartman
Date: Wed Jul 24 2019 - 15:57:23 EST

From: Luis Henriques <lhenriques@xxxxxxxx>

commit d31d07b97a5e76f41e00eb81dcca740e84aa7782 upstream.

Commit e450f4d1a5d6 ("ceph: pass inclusive lend parameter to
filemap_write_and_wait_range()") fixed the end offset parameter used to
call filemap_write_and_wait_range and invalidate_inode_pages2_range.
Unfortunately it missed truncate_inode_pages_range, introducing a
regression that is easily detected by xfstest generic/130.

The problem is that when doing direct IO it is possible that an extra page
is truncated from the page cache when the end offset is page aligned.
This can cause data loss if that page hasn't been sync'ed to the OSDs.

While there, change code to use PAGE_ALIGN macro instead.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: e450f4d1a5d6 ("ceph: pass inclusive lend parameter to filemap_write_and_wait_range()")
Signed-off-by: Luis Henriques <lhenriques@xxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

fs/ceph/file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1006,7 +1006,7 @@ ceph_direct_read_write(struct kiocb *ioc
* may block.
truncate_inode_pages_range(inode->i_mapping, pos,
- (pos+len) | (PAGE_SIZE - 1));
+ PAGE_ALIGN(pos + len) - 1);

req->r_mtime = mtime;