[patch 2/4] vfs: utimes cleanup

Untange the mess that is do_utimes().  Add kerneldoc comment to
do_utimes().

CC: Ulrich Drepper <drepper@redhat.com>
CC: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/utimes.c b/fs/utimes.c
index ecf8941..8e09dbd 100644 (file)
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -48,54 +48,15 @@ static bool nsec_valid(long nsec)
        return nsec >= 0 && nsec <= 999999999;
 }
 
-/* If times==NULL, set access and modification to current time,
- * must be owner or have write permission.
- * Else, update from *times, must be owner or super user.
- */
-long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags)
+static int utimes_common(struct path *path, struct timespec *times)
 {
        int error;
-       struct nameidata nd;
-       struct dentry *dentry;
-       struct inode *inode;
        struct iattr newattrs;
-       struct file *f = NULL;
-       struct vfsmount *mnt;
-
-       error = -EINVAL;
-       if (times && (!nsec_valid(times[0].tv_nsec) ||
-                     !nsec_valid(times[1].tv_nsec))) {
-               goto out;
-       }
-
-       if (flags & ~AT_SYMLINK_NOFOLLOW)
-               goto out;
-
-       if (filename == NULL && dfd != AT_FDCWD) {
-               error = -EINVAL;
-               if (flags & AT_SYMLINK_NOFOLLOW)
-                       goto out;
-
-               error = -EBADF;
-               f = fget(dfd);
-               if (!f)
-                       goto out;
-               dentry = f->f_path.dentry;
-               mnt = f->f_path.mnt;
-       } else {
-               error = __user_walk_fd(dfd, filename, (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW, &nd);
-               if (error)
-                       goto out;
-
-               dentry = nd.path.dentry;
-               mnt = nd.path.mnt;
-       }
-
-       inode = dentry->d_inode;
+       struct inode *inode = path->dentry->d_inode;
 
-       error = mnt_want_write(mnt);
+       error = mnt_want_write(path->mnt);
        if (error)
-               goto dput_and_out;
+               goto out;
 
        if (times && times[0].tv_nsec == UTIME_NOW &&
                     times[1].tv_nsec == UTIME_NOW)
@@ -145,15 +106,70 @@ long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags
                }
        }
        mutex_lock(&inode->i_mutex);
-       error = notify_change(dentry, &newattrs);
+       error = notify_change(path->dentry, &newattrs);
        mutex_unlock(&inode->i_mutex);
+
 mnt_drop_write_and_out:
-       mnt_drop_write(mnt);
-dput_and_out:
-       if (f)
-               fput(f);
-       else
+       mnt_drop_write(path->mnt);
+out:
+       return error;
+}
+
+/*
+ * do_utimes - change times on filename or file descriptor
+ * @dfd: open file descriptor, -1 or AT_FDCWD
+ * @filename: path name or NULL
+ * @times: new times or NULL
+ * @flags: zero or more flags (only AT_SYMLINK_NOFOLLOW for the moment)
+ *
+ * If filename is NULL and dfd refers to an open file, then operate on
+ * the file.  Otherwise look up filename, possibly using dfd as a
+ * starting point.
+ *
+ * If times==NULL, set access and modification to current time,
+ * must be owner or have write permission.
+ * Else, update from *times, must be owner or super user.
+ */
+long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags)
+{
+       int error = -EINVAL;
+
+       if (times && (!nsec_valid(times[0].tv_nsec) ||
+                     !nsec_valid(times[1].tv_nsec))) {
+               goto out;
+       }
+
+       if (flags & ~AT_SYMLINK_NOFOLLOW)
+               goto out;
+
+       if (filename == NULL && dfd != AT_FDCWD) {
+               struct file *file;
+
+               if (flags & AT_SYMLINK_NOFOLLOW)
+                       goto out;
+
+               file = fget(dfd);
+               error = -EBADF;
+               if (!file)
+                       goto out;
+
+               error = utimes_common(&file->f_path, times);
+               fput(file);
+       } else {
+               struct nameidata nd;
+               int lookup_flags = 0;
+
+               if (!(flags & AT_SYMLINK_NOFOLLOW))
+                       lookup_flags |= LOOKUP_FOLLOW;
+
+               error = __user_walk_fd(dfd, filename, lookup_flags, &nd);
+               if (error)
+                       goto out;
+
+               error = utimes_common(&nd.path, times);
                path_put(&nd.path);
+       }
+
 out:
        return error;
 }