dcache: extrace and use d_unlinked()

d_unlinked() will be used in middle-term to ban checkpointing when opened
but unlinked file is detected, and in long term, to detect such situation
and special case on it.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 7 insertions, 8 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index 75659a6fd1f8..9e5cd3c3a6ba 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1910,7 +1910,7 @@ char *__d_path(const struct path *path, struct path *root,
 
         spin_lock(&vfsmount_lock);
         prepend(&end, &buflen, "\0", 1);
-        if (!IS_ROOT(dentry) && d_unhashed(dentry) &&
+        if (d_unlinked(dentry) &&
                 (prepend(&end, &buflen, " (deleted)", 10) != 0))
                         goto Elong;
 
@@ -2035,7 +2035,7 @@ char *dentry_path(struct dentry *dentry, char *buf, int buflen)
 
         spin_lock(&dcache_lock);
         prepend(&end, &buflen, "\0", 1);
-        if (!IS_ROOT(dentry) && d_unhashed(dentry) &&
+        if (d_unlinked(dentry) &&
                 (prepend(&end, &buflen, "//deleted", 9) != 0))
                         goto Elong;
         if (buflen < 1)
@@ -2097,9 +2097,8 @@ SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size)
         read_unlock(&current->fs->lock);
 
         error = -ENOENT;
-        /* Has the current directory has been unlinked? */
         spin_lock(&dcache_lock);
-        if (IS_ROOT(pwd.dentry) || !d_unhashed(pwd.dentry)) {
+        if (!d_unlinked(pwd.dentry)) {
                 unsigned long len;
                 struct path tmp = root;
                 char * cwd;
diff --git a/fs/namespace.c b/fs/namespace.c
index 120b8a6b99ed..7e537f0393b5 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1384,7 +1384,7 @@ static int graft_tree(struct vfsmount *mnt, struct path *path)
                 goto out_unlock;
 
         err = -ENOENT;
-        if (IS_ROOT(path->dentry) || !d_unhashed(path->dentry))
+        if (!d_unlinked(path->dentry))
                 err = attach_recursive_mnt(mnt, path, NULL);
 out_unlock:
         mutex_unlock(&path->dentry->d_inode->i_mutex);
@@ -1566,7 +1566,7 @@ static int do_move_mount(struct path *path, char *old_name)
         if (IS_DEADDIR(path->dentry->d_inode))
                 goto out1;
 
-        if (!IS_ROOT(path->dentry) && d_unhashed(path->dentry))
+        if (d_unlinked(path->dentry))
                 goto out1;
 
         err = -EINVAL;
@@ -2129,9 +2129,9 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
         error = -ENOENT;
         if (IS_DEADDIR(new.dentry->d_inode))
                 goto out2;
-        if (d_unhashed(new.dentry) && !IS_ROOT(new.dentry))
+        if (d_unlinked(new.dentry))
                 goto out2;
-        if (d_unhashed(old.dentry) && !IS_ROOT(old.dentry))
+        if (d_unlinked(old.dentry))
                 goto out2;
         error = -EBUSY;
         if (new.mnt == root.mnt ||