untangling do_lookup() - isolate !dentry stuff from the rest of it.

Duplicate the revalidation-related parts into if (!dentry) branch.
Next step will be to pull them under i_mutex.

This and the next 8 commits are more or less a splitup of patch
by Miklos; folks, when you are working with something that convoluted,
carve your patches up into easily reviewed steps, especially when
a lot of codepaths involved are rarely hit...

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

1 files changed, 16 insertions, 1 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 907e24785576..157f3debbf98 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1194,6 +1194,21 @@ retry:
                         status = 1;
                 }
                 mutex_unlock(&dir->i_mutex);
+                if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE) && need_reval)
+                        status = d_revalidate(dentry, nd);
+                if (unlikely(status <= 0)) {
+                        if (status < 0) {
+                                dput(dentry);
+                                return status;
+                        }
+                        if (!d_invalidate(dentry)) {
+                                dput(dentry);
+                                dentry = NULL;
+                                need_reval = 1;
+                                goto retry;
+                        }
+                }
+                goto done;
         }
         if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE) && need_reval)
                 status = d_revalidate(dentry, nd);
@@ -1209,7 +1224,7 @@ retry:
                         goto retry;
                 }
         }
-
+done:
         path->mnt = mnt;
         path->dentry = dentry;
         err = follow_managed(path, nd->flags);