vfs: add i_op->dentry_open()

Add a new inode operation i_op->dentry_open().  This is for stacked filesystems
that want to return a struct file from a different filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

1 files changed, 6 insertions, 3 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 43927d14db67..75306b3c9526 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3064,9 +3064,12 @@ finish_open_created:
         error = may_open(&nd->path, acc_mode, open_flag);
         if (error)
                 goto out;
-        file->f_path.mnt = nd->path.mnt;
-        error = finish_open(file, nd->path.dentry, NULL, opened);
-        if (error) {
+
+        BUG_ON(*opened & FILE_OPENED); /* once it's opened, it's opened */
+        error = vfs_open(&nd->path, file, current_cred());
+        if (!error) {
+                *opened |= FILE_OPENED;
+        } else {
                 if (error == -EOPENSTALE)
                         goto stale_open;
                 goto out;