[PATCH] ufs: handle truncated pages

ufs_get_locked_page is called twice in ufs code, one time in ufs_truncate
path(we allocated last block), and another time when fragments are
reallocated.  In ideal world in the second case on allocation/free block
layer we should not know that things like `truncate' exists, but now with
such crutch like ufs_get_locked_page we can (or should?) skip truncated
pages.

Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c
index b01804b..b823814 100644 (file)
--- a/fs/ufs/balloc.c
+++ b/fs/ufs/balloc.c
@@ -248,7 +248,7 @@ static void ufs_change_blocknr(struct inode *inode, unsigned int baseblk,
 
                if (likely(cur_index != index)) {
                        page = ufs_get_locked_page(mapping, index);
-                       if (IS_ERR(page))
+                       if (!page || IS_ERR(page)) /* it was truncated or EIO */
                                continue;
                } else
                        page = locked_page;

diff --git a/fs/ufs/util.c b/fs/ufs/util.c
index 005d681..22f820a 100644 (file)
--- a/fs/ufs/util.c
+++ b/fs/ufs/util.c
@@ -251,7 +251,6 @@ struct page *ufs_get_locked_page(struct address_space *mapping,
 {
        struct page *page;
 
-try_again:
        page = find_lock_page(mapping, index);
        if (!page) {
                page = read_cache_page(mapping, index,
@@ -271,7 +270,8 @@ try_again:
                        /* Truncate got there first */
                        unlock_page(page);
                        page_cache_release(page);
-                       goto try_again;
+                       page = NULL;
+                       goto out;
                }
 
                if (!PageUptodate(page) || PageError(page)) {