1 files changed, 75 insertions, 24 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index ce8cb926526b..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;
@@ -450,7 +450,8 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 			nfs_refresh_inode(dentry->d_inode, entry->fattr);
 			goto out;
 		} else {
-			d_drop(dentry);
+			if (d_invalidate(dentry) != 0)
+				goto out;
 			dput(dentry);
 		}
 	}
@@ -628,7 +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);
@@ -659,7 +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);
 }
 
@@ -763,7 +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",
@@ -870,7 +871,7 @@ out:
 	return res;
 }
 
-static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
+static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int whence)
 {
 	struct dentry *dentry = filp->f_path.dentry;
 	struct inode *inode = dentry->d_inode;
@@ -879,10 +880,10 @@ static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
 	dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
 			dentry->d_parent->d_name.name,
 			dentry->d_name.name,
-			offset, origin);
+			offset, whence);
 
 	mutex_lock(&inode->i_mutex);
-	switch (origin) {
+	switch (whence) {
 		case 1:
 			offset += filp->f_pos;
 		case 0:
@@ -978,10 +979,11 @@ static int nfs_is_exclusive_create(struct inode *dir, unsigned int flags)
  * particular file and the "nocto" mount flag is not set.
  *
  */
-static inline
+static
 int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags)
 {
 	struct nfs_server *server = NFS_SERVER(inode);
+	int ret;
 
 	if (IS_AUTOMOUNT(inode))
 		return 0;
@@ -992,9 +994,13 @@ int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags)
 	if ((flags & LOOKUP_OPEN) && !(server->flags & NFS_MOUNT_NOCTO) &&
 	    (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
 		goto out_force;
-	return 0;
+out:
+	return (inode->i_nlink == 0) ? -ENOENT : 0;
 out_force:
-	return __nfs_revalidate_inode(server, inode);
+	ret = __nfs_revalidate_inode(server, inode);
+	if (ret != 0)
+		return ret;
+	goto out;
 }
 
 /*
@@ -1100,6 +1106,8 @@ out_set_verifier:
 out_zap_parent:
 	nfs_zap_caches(dir);
  out_bad:
+	nfs_free_fattr(fattr);
+	nfs_free_fhandle(fhandle);
 	nfs_mark_for_revalidate(dir);
 	if (inode && S_ISDIR(inode->i_mode)) {
 		/* Purge readdir caches. */
@@ -1112,8 +1120,6 @@ out_zap_parent:
 		shrink_dcache_parent(dentry);
 	}
 	d_drop(dentry);
-	nfs_free_fattr(fattr);
-	nfs_free_fhandle(fhandle);
 	dput(parent);
 	dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n",
 			__func__, dentry->d_parent->d_name.name,
@@ -1130,6 +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)
@@ -1155,11 +1200,14 @@ static int nfs_dentry_delete(const struct dentry *dentry)
 
 }
 
+/* Ensure that we revalidate inode->i_nlink */
 static void nfs_drop_nlink(struct inode *inode)
 {
 	spin_lock(&inode->i_lock);
-	if (inode->i_nlink > 0)
-		drop_nlink(inode);
+	/* drop the inode if we're reasonably sure this is the last link */
+	if (inode->i_nlink == 1)
+		clear_nlink(inode);
+	NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATTR;
 	spin_unlock(&inode->i_lock);
 }
 
@@ -1174,8 +1222,8 @@ static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
 		NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
 
 	if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
-		drop_nlink(inode);
 		nfs_complete_unlink(dentry, inode);
+		nfs_drop_nlink(inode);
 	}
 	iput(inode);
 }
@@ -1193,6 +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,
@@ -1646,10 +1695,8 @@ static int nfs_safe_remove(struct dentry *dentry)
 	if (inode != NULL) {
 		NFS_PROTO(inode)->return_delegation(inode);
 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
-		/* The VFS may want to delete this inode */
 		if (error == 0)
 			nfs_drop_nlink(inode);
-		nfs_mark_for_revalidate(inode);
 	} else
 		error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
 	if (error == -ENOENT)
@@ -2146,12 +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;
 }