fuse: allow kernel to access "direct_io" files
Allow the kernel read and write on "direct_io" files. This is
necessary for nfs export and execute support.
The implementation is simple: if an access from the kernel is
detected, don't perform get_user_pages(), just use the kernel address
provided by the requester to copy from/to the userspace filesystem.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 06da052..8b8eebc 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1032,6 +1032,7 @@
fuse_put_request(fc, req);
return -ENOMEM;
}
+ req->out.argpages = 1;
req->num_pages = 1;
req->pages[0] = page;
fuse_read_fill(req, file, inode, file->f_pos, PAGE_SIZE, FUSE_READDIR);