firmware: Kconfig: ROCKCHIP_SIP depends on HAVE_ARM_SMCCC and ARCH_ROCKCHIP

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

diff --git a/fs/attr.c b/fs/attr.c
index 66fa6251c398d7584042c7169967f54bfed4278e..11be2265a2d55cb0688231698770b29ee357b0f1 100644 (file)
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -167,7 +167,27 @@ void setattr_copy(struct inode *inode, const struct iattr *attr)
 }
 EXPORT_SYMBOL(setattr_copy);
 
-int notify_change(struct dentry * dentry, struct iattr * attr)
+/**
+ * notify_change - modify attributes of a filesytem object
+ * @dentry:    object affected
+ * @iattr:     new attributes
+ * @delegated_inode: returns inode, if the inode is delegated
+ *
+ * The caller must hold the i_mutex on the affected object.
+ *
+ * If notify_change discovers a delegation in need of breaking,
+ * it will return -EWOULDBLOCK and return a reference to the inode in
+ * delegated_inode.  The caller should then break the delegation and
+ * retry.  Because breaking a delegation may take a long time, the
+ * caller should drop the i_mutex before doing so.
+ *
+ * Alternatively, a caller may pass NULL for delegated_inode.  This may
+ * be appropriate for callers that expect the underlying filesystem not
+ * to be NFS exported.  Also, passing NULL is fine for callers holding
+ * the file open for write, as there can be no conflicting delegation in
+ * that case.
+ */
+int notify_change2(struct vfsmount *mnt, struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
 {
        struct inode *inode = dentry->d_inode;
        umode_t mode = inode->i_mode;
@@ -182,6 +202,21 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
                        return -EPERM;
        }
 
+       /*
+        * If utimes(2) and friends are called with times == NULL (or both
+        * times are UTIME_NOW), then we need to check for write permission
+        */
+       if (ia_valid & ATTR_TOUCH) {
+               if (IS_IMMUTABLE(inode))
+                       return -EPERM;
+
+               if (!inode_owner_or_capable(inode)) {
+                       error = inode_permission(inode, MAY_WRITE);
+                       if (error)
+                               return error;
+               }
+       }
+
        if ((ia_valid & ATTR_MODE)) {
                umode_t amode = attr->ia_mode;
                /* Flag setting protected by i_mutex */
@@ -236,10 +271,15 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
                return 0;
 
        error = security_inode_setattr(dentry, attr);
+       if (error)
+               return error;
+       error = try_break_deleg(inode, delegated_inode);
        if (error)
                return error;
 
-       if (inode->i_op->setattr)
+       if (mnt && inode->i_op->setattr2)
+               error = inode->i_op->setattr2(mnt, dentry, attr);
+       else if (inode->i_op->setattr)
                error = inode->i_op->setattr(dentry, attr);
        else
                error = simple_setattr(dentry, attr);
@@ -252,4 +292,10 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
 
        return error;
 }
+EXPORT_SYMBOL(notify_change2);
+
+int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
+{
+       return notify_change2(NULL, dentry, attr, delegated_inode);
+}
 EXPORT_SYMBOL(notify_change);