1 files changed, 24 insertions, 30 deletions

diff --git a/fs/attr.c b/fs/attr.c
index 9caf63d20d03..795f231d00e8 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -230,7 +230,7 @@ EXPORT_SYMBOL(setattr_prepare);
  * @inode:	the inode to be truncated
  * @offset:	the new size to assign to the inode
  *
- * inode_newsize_ok must be called with i_mutex held.
+ * inode_newsize_ok must be called with i_rwsem held exclusively.
  *
  * inode_newsize_ok will check filesystem limits and ulimits to check that the
  * new inode size is within limits. inode_newsize_ok will also send SIGXFSZ
@@ -286,20 +286,12 @@ static void setattr_copy_mgtime(struct inode *inode, const struct iattr *attr)
 	unsigned int ia_valid = attr->ia_valid;
 	struct timespec64 now;
 
-	if (ia_valid & ATTR_CTIME) {
-		/*
-		 * In the case of an update for a write delegation, we must respect
-		 * the value in ia_ctime and not use the current time.
-		 */
-		if (ia_valid & ATTR_DELEG)
-			now = inode_set_ctime_deleg(inode, attr->ia_ctime);
-		else
-			now = inode_set_ctime_current(inode);
-	} else {
-		/* If ATTR_CTIME isn't set, then ATTR_MTIME shouldn't be either. */
-		WARN_ON_ONCE(ia_valid & ATTR_MTIME);
+	if (ia_valid & ATTR_CTIME_SET)
+		now = inode_set_ctime_deleg(inode, attr->ia_ctime);
+	else if (ia_valid & ATTR_CTIME)
+		now = inode_set_ctime_current(inode);
+	else
 		now = current_time(inode);
-	}
 
 	if (ia_valid & ATTR_ATIME_SET)
 		inode_set_atime_to_ts(inode, attr->ia_atime);
@@ -318,7 +310,7 @@ static void setattr_copy_mgtime(struct inode *inode, const struct iattr *attr)
  * @inode:	the inode to be updated
  * @attr:	the new attributes
  *
- * setattr_copy must be called with i_mutex held.
+ * setattr_copy must be called with i_rwsem held exclusively.
  *
  * setattr_copy updates the inode's metadata with that specified
  * in attr on idmapped mounts. Necessary permission checks to determine
@@ -359,12 +351,11 @@ void setattr_copy(struct mnt_idmap *idmap, struct inode *inode,
 		inode_set_atime_to_ts(inode, attr->ia_atime);
 	if (ia_valid & ATTR_MTIME)
 		inode_set_mtime_to_ts(inode, attr->ia_mtime);
-	if (ia_valid & ATTR_CTIME) {
-		if (ia_valid & ATTR_DELEG)
-			inode_set_ctime_deleg(inode, attr->ia_ctime);
-		else
-			inode_set_ctime_to_ts(inode, attr->ia_ctime);
-	}
+
+	if (ia_valid & ATTR_CTIME_SET)
+		inode_set_ctime_deleg(inode, attr->ia_ctime);
+	else if (ia_valid & ATTR_CTIME)
+		inode_set_ctime_to_ts(inode, attr->ia_ctime);
 }
 EXPORT_SYMBOL(setattr_copy);
 
@@ -403,13 +394,13 @@ EXPORT_SYMBOL(may_setattr);
  * @attr:	new attributes
  * @delegated_inode: returns inode, if the inode is delegated
  *
- * The caller must hold the i_mutex on the affected object.
+ * The caller must hold the i_rwsem exclusively 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.
+ * caller should drop the i_rwsem before doing so.
  *
  * Alternatively, a caller may pass NULL for delegated_inode.  This may
  * be appropriate for callers that expect the underlying filesystem not
@@ -456,22 +447,25 @@ int notify_change(struct mnt_idmap *idmap, struct dentry *dentry,
 		if (S_ISLNK(inode->i_mode))
 			return -EOPNOTSUPP;
 
-		/* Flag setting protected by i_mutex */
+		/* Flag setting protected by i_rwsem */
 		if (is_sxid(attr->ia_mode))
 			inode->i_flags &= ~S_NOSEC;
 	}
 
 	now = current_time(inode);
 
-	attr->ia_ctime = now;
-	if (!(ia_valid & ATTR_ATIME_SET))
-		attr->ia_atime = now;
-	else
+	if (ia_valid & ATTR_ATIME_SET)
 		attr->ia_atime = timestamp_truncate(attr->ia_atime, inode);
-	if (!(ia_valid & ATTR_MTIME_SET))
-		attr->ia_mtime = now;
 	else
+		attr->ia_atime = now;
+	if (ia_valid & ATTR_CTIME_SET)
+		attr->ia_ctime = timestamp_truncate(attr->ia_ctime, inode);
+	else
+		attr->ia_ctime = now;
+	if (ia_valid & ATTR_MTIME_SET)
 		attr->ia_mtime = timestamp_truncate(attr->ia_mtime, inode);
+	else
+		attr->ia_mtime = now;
 
 	if (ia_valid & ATTR_KILL_PRIV) {
 		error = security_inode_need_killpriv(dentry);