__nd_alloc_stack(): make it return bool

... and adjust the caller (reserve_stack()).  Rename to nd_alloc_stack(),
while we are at it.

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

diff --git a/fs/namei.c b/fs/namei.c
index 0539a26..7a95a3f 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -529,24 +529,17 @@ static void restore_nameidata(void)
                kfree(now->stack);
 }
 
-static int __nd_alloc_stack(struct nameidata *nd)
+static bool nd_alloc_stack(struct nameidata *nd)
 {
        struct saved *p;
 
-       if (nd->flags & LOOKUP_RCU) {
-               p= kmalloc_array(MAXSYMLINKS, sizeof(struct saved),
-                                 GFP_ATOMIC);
-               if (unlikely(!p))
-                       return -ECHILD;
-       } else {
-               p= kmalloc_array(MAXSYMLINKS, sizeof(struct saved),
-                                 GFP_KERNEL);
-               if (unlikely(!p))
-                       return -ENOMEM;
-       }
+       p= kmalloc_array(MAXSYMLINKS, sizeof(struct saved),
+                        nd->flags & LOOKUP_RCU ? GFP_ATOMIC : GFP_KERNEL);
+       if (unlikely(!p))
+               return false;
        memcpy(p, nd->internal, sizeof(nd->internal));
        nd->stack = p;
-       return 0;
+       return true;
 }
 
 /**
@@ -1573,8 +1566,6 @@ static inline int may_lookup(struct nameidata *nd)
 
 static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq)
 {
-       int error;
-
        if (unlikely(nd->total_link_count++ >= MAXSYMLINKS))
                return -ELOOP;
 
@@ -1582,21 +1573,21 @@ static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq)
                return 0;
        if (likely(nd->stack != nd->internal))
                return 0;
-
-       error = __nd_alloc_stack(nd);
-       if (likely(!error))
+       if (likely(nd_alloc_stack(nd)))
                return 0;
-       if (error == -ECHILD) {
-               // we must grab link first
+
+       if (nd->flags & LOOKUP_RCU) {
+               // we need to grab link before we do unlazy.  And we can't skip
+               // unlazy even if we fail to grab the link - cleanup needs it
                bool grabbed_link = legitimize_path(nd, link, seq);
-               // ... and we must unlazy to be able to clean up
-               error = unlazy_walk(nd);
-               if (unlikely(!grabbed_link))
-                       error = -ECHILD;
-               if (!error)
-                       error = __nd_alloc_stack(nd);
+
+               if (unlazy_walk(nd) != 0 || !grabbed_link)
+                       return -ECHILD;
+
+               if (nd_alloc_stack(nd))
+                       return 0;
        }
-       return error;
+       return -ENOMEM;
 }
 
 enum {WALK_TRAILING = 1, WALK_MORE = 2, WALK_NOFOLLOW = 4};