1 files changed, 54 insertions, 10 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 32e6c53520e2..f23f455be42b 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -281,7 +281,7 @@ int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, nfs_readdir_des
 
         for (i = 0; i < array->size; i++) {
                 if (array->array[i].cookie == *desc->dir_cookie) {
-                        struct nfs_inode *nfsi = NFS_I(desc->file->f_path.dentry->d_inode);
+                        struct nfs_inode *nfsi = NFS_I(file_inode(desc->file));
                         struct nfs_open_dir_context *ctx = desc->file->private_data;
 
                         new_pos = desc->current_index + i;
@@ -629,7 +629,7 @@ out:
 static
 int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page* page)
 {
-        struct inode    *inode = desc->file->f_path.dentry->d_inode;
+        struct inode    *inode = file_inode(desc->file);
         int ret;
 
         ret = nfs_readdir_xdr_to_array(desc, page, inode);
@@ -660,7 +660,7 @@ void cache_page_release(nfs_readdir_descriptor_t *desc)
 static
 struct page *get_cache_page(nfs_readdir_descriptor_t *desc)
 {
-        return read_cache_page(desc->file->f_path.dentry->d_inode->i_mapping,
+        return read_cache_page(file_inode(desc->file)->i_mapping,
                         desc->page_index, (filler_t *)nfs_readdir_filler, desc);
 }
 
@@ -764,7 +764,7 @@ int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
 {
         struct page     *page = NULL;
         int             status;
-        struct inode *inode = desc->file->f_path.dentry->d_inode;
+        struct inode *inode = file_inode(desc->file);
         struct nfs_open_dir_context *ctx = desc->file->private_data;
 
         dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n",
@@ -1136,6 +1136,45 @@ out_error:
 }
 
 /*
+ * A weaker form of d_revalidate for revalidating just the dentry->d_inode
+ * when we don't really care about the dentry name. This is called when a
+ * pathwalk ends on a dentry that was not found via a normal lookup in the
+ * parent dir (e.g.: ".", "..", procfs symlinks or mountpoint traversals).
+ *
+ * In this situation, we just want to verify that the inode itself is OK
+ * since the dentry might have changed on the server.
+ */
+static int nfs_weak_revalidate(struct dentry *dentry, unsigned int flags)
+{
+        int error;
+        struct inode *inode = dentry->d_inode;
+
+        /*
+         * I believe we can only get a negative dentry here in the case of a
+         * procfs-style symlink. Just assume it's correct for now, but we may
+         * eventually need to do something more here.
+         */
+        if (!inode) {
+                dfprintk(LOOKUPCACHE, "%s: %s/%s has negative inode\n",
+                                __func__, dentry->d_parent->d_name.name,
+                                dentry->d_name.name);
+                return 1;
+        }
+
+        if (is_bad_inode(inode)) {
+                dfprintk(LOOKUPCACHE, "%s: %s/%s has dud inode\n",
+                                __func__, dentry->d_parent->d_name.name,
+                                dentry->d_name.name);
+                return 0;
+        }
+
+        error = nfs_revalidate_inode(NFS_SERVER(inode), inode);
+        dfprintk(LOOKUPCACHE, "NFS: %s: inode %lu is %s\n",
+                        __func__, inode->i_ino, error ? "invalid" : "valid");
+        return !error;
+}
+
+/*
  * This is called from dput() when d_count is going to 0.
  */
 static int nfs_dentry_delete(const struct dentry *dentry)
@@ -1202,6 +1241,7 @@ static void nfs_d_release(struct dentry *dentry)
 
 const struct dentry_operations nfs_dentry_operations = {
         .d_revalidate   = nfs_lookup_revalidate,
+        .d_weak_revalidate      = nfs_weak_revalidate,
         .d_delete       = nfs_dentry_delete,
         .d_iput         = nfs_dentry_iput,
         .d_automount    = nfs_d_automount,
@@ -2153,12 +2193,16 @@ static int nfs_open_permission_mask(int openflags)
 {
         int mask = 0;
 
-        if ((openflags & O_ACCMODE) != O_WRONLY)
-                mask |= MAY_READ;
-        if ((openflags & O_ACCMODE) != O_RDONLY)
-                mask |= MAY_WRITE;
-        if (openflags & __FMODE_EXEC)
-                mask |= MAY_EXEC;
+        if (openflags & __FMODE_EXEC) {
+                /* ONLY check exec rights */
+                mask = MAY_EXEC;
+        } else {
+                if ((openflags & O_ACCMODE) != O_WRONLY)
+                        mask |= MAY_READ;
+                if ((openflags & O_ACCMODE) != O_RDONLY)
+                        mask |= MAY_WRITE;
+        }
+
         return mask;
 }