Merge branch 'for-rc' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux

[deliverable/linux.git] / fs / xfs / xfs_file.c

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index ed95e5bb04e692b614983ea83bf870ac373a9b0c..e612a0233710850f34eae93540b098c3ae7cda8c 100644 (file)
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -741,9 +741,20 @@ xfs_file_dax_write(
         * page is inserted into the pagecache when we have to serve a write
         * fault on a hole.  It should never be dirtied and can simply be
         * dropped from the pagecache once we get real data for the page.
+        *
+        * XXX: This is racy against mmap, and there's nothing we can do about
+        * it. dax_do_io() should really do this invalidation internally as
+        * it will know if we've allocated over a holei for this specific IO and
+        * if so it needs to update the mapping tree and invalidate existing
+        * PTEs over the newly allocated range. Remove this invalidation when
+        * dax_do_io() is fixed up.
         */
        if (mapping->nrpages) {
-               ret = invalidate_inode_pages2(mapping);
+               loff_t end = iocb->ki_pos + iov_iter_count(from) - 1;
+
+               ret = invalidate_inode_pages2_range(mapping,
+                                                   iocb->ki_pos >> PAGE_SHIFT,
+                                                   end >> PAGE_SHIFT);
                WARN_ON_ONCE(ret);
        }