summaryrefslogtreecommitdiff
path: root/fs/gfs2
diff options
context:
space:
mode:
authorAndreas Gruenbacher <agruenba@redhat.com>2019-09-06 11:02:38 +0100
committerAndreas Gruenbacher <agruenba@redhat.com>2019-09-06 22:54:23 +0200
commitb473bc2dcd5ad7c487f252d9d2b74ace70308b1f (patch)
treeb8c5b584423feb174c308cce5c51544cd95004b8 /fs/gfs2
parentad26967b9afa7faee22c3b79370cb5d9ab553493 (diff)
gfs2: Improve mmap write vs. truncate consistency
On filesystems with a block size smaller than PAGE_SIZE, page_mkwrite is called for each memory-mapped page before that page can be written to. When such a memory-mapped file is truncated down to size x which is not a multiple of the page size and then back to a larger size, the page straddling size x can end up with a partial block mapping. In that case, make sure to mark that page read-only so that page_mkwrite will be called before the page can be written to the next time. (There is no point in marking the page straddling size x read-only when truncating down as writing to memory beyond the end of the file will result in SIGBUS instead of growing the file.) Fixes xfstests generic/029, generic/030 on filesystems with a block size smaller than PAGE_SIZE. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Diffstat (limited to 'fs/gfs2')
-rw-r--r--fs/gfs2/bmap.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index 2043a728f281..9ef543dd38e2 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -2139,7 +2139,7 @@ static int do_grow(struct inode *inode, u64 size)
if (error)
goto do_end_trans;
- i_size_write(inode, size);
+ truncate_setsize(inode, size);
ip->i_inode.i_mtime = ip->i_inode.i_ctime = current_time(&ip->i_inode);
gfs2_trans_add_meta(ip->i_gl, dibh);
gfs2_dinode_out(ip, dibh->b_data);