[PATCH] v9fs: add readpage support

v9fs mmap support was originally removed from v9fs at Al Viro's request,
but recently there have been requests from folks who want readpage
functionality (primarily to enable execution of files mounted via 9P).
This patch adds readpage support (but not writepage which contained most of
the objectionable code).  It passes fsx-linux (and other regressions) so it
should be relatively safe.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 6852f0eb96ed..c7e14d917215 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -289,6 +289,9 @@ v9fs_file_write(struct file *filp, const char __user * data,
                 total += result;
         } while (count);
 
+        if(inode->i_mapping->nrpages)
+                invalidate_inode_pages2(inode->i_mapping);
+
         return total;
 }
 
@@ -299,4 +302,5 @@ struct file_operations v9fs_file_operations = {
         .open = v9fs_file_open,
         .release = v9fs_dir_release,
         .lock = v9fs_file_lock,
+        .mmap = generic_file_mmap,
 };