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/data.c b/fs/f2fs/data.c
index eba7e84..2db9380 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -240,7 +240,7 @@
if (dn.data_blkaddr == NULL_ADDR)
return ERR_PTR(-ENOENT);
-
+repeat:
page = grab_cache_page(mapping, index);
if (!page)
return ERR_PTR(-ENOMEM);
@@ -260,6 +260,10 @@
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
+ if (page->mapping != mapping) {
+ f2fs_put_page(page, 1);
+ goto repeat;
+ }
return page;
}
@@ -291,7 +295,7 @@
}
}
f2fs_put_dnode(&dn);
-
+repeat:
page = grab_cache_page(mapping, index);
if (!page)
return ERR_PTR(-ENOMEM);
@@ -311,6 +315,10 @@
f2fs_put_page(page, 1);
return ERR_PTR(-EIO);
}
+ if (page->mapping != mapping) {
+ f2fs_put_page(page, 1);
+ goto repeat;
+ }
}
if (new_i_size &&
@@ -611,7 +619,7 @@
*fsdata = NULL;
f2fs_balance_fs(sbi);
-
+repeat:
page = grab_cache_page_write_begin(mapping, index, flags);
if (!page)
return -ENOMEM;
@@ -656,6 +664,10 @@
f2fs_put_page(page, 1);
return -EIO;
}
+ if (page->mapping != mapping) {
+ f2fs_put_page(page, 1);
+ goto repeat;
+ }
}
out:
SetPageUptodate(page);
