[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>

1 files changed, 65 insertions, 49 deletions

diff --git a/fs/utimes.c b/fs/utimes.c
index ecf8941ba34a..8e09dbdfd7f5 100644
--- 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;
 }