namei: change calling conventions for lookup_{fast,slow} and follow_managed()

Have lookup_fast() return 1 on success and 0 on "need to fall back";
lookup_slow() and follow_managed() return positive (1) on success.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index edec6b8..fc6c545 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1220,8 +1220,8 @@ static int follow_managed(struct path *path, struct nameidata *nd)
 
        if (need_mntput && path->mnt == mnt)
                mntput(path->mnt);
-       if (ret == -EISDIR)
-               ret = 0;
+       if (ret == -EISDIR || !ret)
+               ret = 1;
        if (need_mntput)
                nd->flags |= LOOKUP_JUMPED;
        if (unlikely(ret < 0))
@@ -1533,7 +1533,7 @@ static int lookup_fast(struct nameidata *nd,
                if (unlikely(!dentry)) {
                        if (unlazy_walk(nd, NULL, 0))
                                return -ECHILD;
-                       return 1;
+                       return 0;
                }
 
                /*
@@ -1573,22 +1573,20 @@ static int lookup_fast(struct nameidata *nd,
                        path->mnt = mnt;
                        path->dentry = dentry;
                        if (likely(__follow_mount_rcu(nd, path, inode, seqp)))
-                               return 0;
+                               return 1;
                        if (unlazy_walk(nd, dentry, seq))
                                return -ECHILD;
                }
        } else {
                dentry = __d_lookup(parent, &nd->last);
                if (unlikely(!dentry))
-                       return 1;
+                       return 0;
                if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE))
                        status = d_revalidate(dentry, nd->flags);
        }
        if (unlikely(status <= 0)) {
-               if (!status) {
+               if (!status)
                        d_invalidate(dentry);
-                       status = 1;
-               }
                dput(dentry);
                return status;
        }
@@ -1600,7 +1598,7 @@ static int lookup_fast(struct nameidata *nd,
        path->mnt = mnt;
        path->dentry = dentry;
        err = follow_managed(path, nd);
-       if (likely(!err))
+       if (likely(err > 0))
                *inode = d_backing_inode(path->dentry);
        return err;
 }
@@ -1724,7 +1722,7 @@ static int walk_component(struct nameidata *nd, int flags)
                return err;
        }
        err = lookup_fast(nd, &path, &inode, &seq);
-       if (unlikely(err)) {
+       if (unlikely(err <= 0)) {
                if (err < 0)
                        return err;
 
@@ -3101,7 +3099,7 @@ static int do_last(struct nameidata *nd,
                        nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
                /* we _can_ be in RCU mode here */
                error = lookup_fast(nd, &path, &inode, &seq);
-               if (likely(!error))
+               if (likely(error > 0))
                        goto finish_lookup;
 
                if (error < 0)