f2fs: check truncation of mapping after lock_page
We call lock_page when we need to update a page after readpage.
Between grab and lock page, the page can be truncated by other thread.
So, we should check the page after lock_page whether it was truncated or not.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index aede910..6ff0172 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -674,6 +674,7 @@
int truncate_inode_blocks(struct inode *inode, pgoff_t from)
{
struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
+ struct address_space *node_mapping = sbi->node_inode->i_mapping;
int err = 0, cont = 1;
int level, offset[4], noffset[4];
unsigned int nofs = 0;
@@ -684,7 +685,7 @@
trace_f2fs_truncate_inode_blocks_enter(inode, from);
level = get_node_path(from, offset, noffset);
-
+restart:
page = get_node_page(sbi, inode->i_ino);
if (IS_ERR(page)) {
trace_f2fs_truncate_inode_blocks_exit(inode, PTR_ERR(page));
@@ -748,6 +749,10 @@
if (offset[1] == 0 &&
rn->i.i_nid[offset[0] - NODE_DIR1_BLOCK]) {
lock_page(page);
+ if (page->mapping != node_mapping) {
+ f2fs_put_page(page, 1);
+ goto restart;
+ }
wait_on_page_writeback(page);
rn->i.i_nid[offset[0] - NODE_DIR1_BLOCK] = 0;
set_page_dirty(page);
@@ -916,7 +921,7 @@
struct address_space *mapping = sbi->node_inode->i_mapping;
struct page *page;
int err;
-
+repeat:
page = grab_cache_page(mapping, nid);
if (!page)
return ERR_PTR(-ENOMEM);
@@ -932,6 +937,10 @@
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
+ if (page->mapping != mapping) {
+ f2fs_put_page(page, 1);
+ goto repeat;
+ }
got_it:
BUG_ON(nid != nid_of_node(page));
mark_page_accessed(page);
@@ -955,7 +964,7 @@
nid = get_nid(parent, start, false);
if (!nid)
return ERR_PTR(-ENOENT);
-
+repeat:
page = grab_cache_page(mapping, nid);
if (!page)
return ERR_PTR(-ENOMEM);
@@ -981,7 +990,10 @@
blk_finish_plug(&plug);
lock_page(page);
-
+ if (page->mapping != mapping) {
+ f2fs_put_page(page, 1);
+ goto repeat;
+ }
page_hit:
if (!PageUptodate(page)) {
f2fs_put_page(page, 1);
