Unionfs: use page_offset() helper

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>

diff --git a/fs/unionfs/mmap.c b/fs/unionfs/mmap.c
index cf9545e54378eea483233d21858421cceff62406..8928e99905878fa1cc21a6e6c78e4e0a66ac0883 100644 (file)
--- a/fs/unionfs/mmap.c
+++ b/fs/unionfs/mmap.c
@@ -179,8 +179,7 @@ static int unionfs_do_readpage(struct file *file, struct page *page)
         * may be a little slower, but a lot safer, as the VFS does a lot of
         * the necessary magic for us.
         */
-       offset = lower_file->f_pos =
-               ((loff_t) page->index << PAGE_CACHE_SHIFT);
+       offset = lower_file->f_pos = page_offset(page);
        old_fs = get_fs();
        set_fs(KERNEL_DS);
        err = vfs_read(lower_file, page_data, PAGE_CACHE_SIZE,
@@ -290,7 +289,7 @@ static int unionfs_commit_write(struct file *file, struct page *page,
        BUG_ON(lower_file == NULL);
 
        page_data = (char *)kmap(page);
-       lower_file->f_pos = ((loff_t) page->index << PAGE_CACHE_SHIFT) + from;
+       lower_file->f_pos = page_offset(page) + from;
 
        /*
         * We use vfs_write instead of copying page data and the
@@ -312,7 +311,7 @@ static int unionfs_commit_write(struct file *file, struct page *page,
 
        inode->i_blocks = lower_inode->i_blocks;
        /* we may have to update i_size */
-       pos = ((loff_t) page->index << PAGE_CACHE_SHIFT) + to;
+       pos = page_offset(page) + to;
        if (pos > i_size_read(inode))
                i_size_write(inode, pos);
        /* if vfs_write succeeded above, sync up our times */