nfs: setattr can only change regular file sizes

[firefly-linux-kernel-4.4.55.git] / fs / nfs / inode.c

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 68921b01b792634be15cb8c213319b0ae1ecd02d..141c9f4a40de31b3237f50a4e5bf8d02e49cce80 100644 (file)
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -505,7 +505,9 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
                attr->ia_valid &= ~ATTR_MODE;
 
        if (attr->ia_valid & ATTR_SIZE) {
-               if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
+               BUG_ON(!S_ISREG(inode->i_mode));
+
+               if (attr->ia_size == i_size_read(inode))
                        attr->ia_valid &= ~ATTR_SIZE;
        }
 
@@ -1002,6 +1004,15 @@ int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
 }
 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
 
+int nfs_revalidate_inode_rcu(struct nfs_server *server, struct inode *inode)
+{
+       if (!(NFS_I(inode)->cache_validity &
+                       (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
+                       && !nfs_attribute_cache_expired(inode))
+               return NFS_STALE(inode) ? -ESTALE : 0;
+       return -ECHILD;
+}
+
 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
 {
        struct nfs_inode *nfsi = NFS_I(inode);