Use the number of pages in the pagecache mapping instead of the
number of pnfs requests which is only slightly related.
Reported-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
 
        /* Optimize common case that writes from 0 to end of file */
        end = DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE);
-       if (end != NFS_I(inode)->npages) {
+       if (end != inode->i_mapping->nrpages) {
                rcu_read_lock();
                end = page_cache_next_hole(mapping, idx + 1, ULONG_MAX);
                rcu_read_unlock();