commit 5d6c31910bc0713e37628dc0ce677dcb13c8ccf4
author Andreas Gruenbacher <agruenba@redhat.com> Thu Sep 29 17:48:42 2016 +0200
committer Al Viro <viro@zeniv.linux.org.uk> Fri Oct 07 20:10:44 2016 -0400
tree a28f96e71f09da2fbbde50882d56e5d5657c0ede
parent f5c244383725a6de06bc62fa7c54c0ea0d942eec

xattr: Add __vfs_{get,set,remove}xattr helpers

Right now, various places in the kernel check for the existence of
getxattr, setxattr, and removexattr inode operations and directly call
those operations.  Switch to helper functions and test for the IOP_XATTR
flag instead.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/xattr.c

diff --git a/fs/xattr.c b/fs/xattr.c
index 1f5d0b4..54a4115 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -136,6 +136,16 @@
 	return inode_permission(inode, mask);
 }
 
+int
+__vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
+	       const void *value, size_t size, int flags)
+{
+	if (!inode->i_op->setxattr)
+		return -EOPNOTSUPP;
+	return inode->i_op->setxattr(dentry, inode, name, value, size, flags);
+}
+EXPORT_SYMBOL(__vfs_setxattr);
+
 /**
  *  __vfs_setxattr_noperm - perform setxattr operation without performing
  *  permission checks.
@@ -163,7 +173,7 @@
 	if (issec)
 		inode->i_flags &= ~S_NOSEC;
 	if (inode->i_op->setxattr) {
-		error = inode->i_op->setxattr(dentry, inode, name, value, size, flags);
+		error = __vfs_setxattr(dentry, inode, name, value, size, flags);
 		if (!error) {
 			fsnotify_xattr(dentry);
 			security_inode_post_setxattr(dentry, name, value,
@@ -275,6 +285,16 @@
 }
 
 ssize_t
+__vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name,
+	       void *value, size_t size)
+{
+	if (!inode->i_op->getxattr)
+		return -EOPNOTSUPP;
+	return inode->i_op->getxattr(dentry, inode, name, value, size);
+}
+EXPORT_SYMBOL(__vfs_getxattr);
+
+ssize_t
 vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size)
 {
 	struct inode *inode = dentry->d_inode;
@@ -301,13 +321,7 @@
 		return ret;
 	}
 nolsm:
-	if (inode->i_op->getxattr)
-		error = inode->i_op->getxattr(dentry, inode, name, value, size);
-	else
-		error = -EOPNOTSUPP;
-
-	return error;
-
+	return __vfs_getxattr(dentry, inode, name, value, size);
 }
 EXPORT_SYMBOL_GPL(vfs_getxattr);
 
@@ -332,14 +346,22 @@
 EXPORT_SYMBOL_GPL(vfs_listxattr);
 
 int
+__vfs_removexattr(struct dentry *dentry, const char *name)
+{
+	struct inode *inode = dentry->d_inode;
+
+	if (!inode->i_op->removexattr)
+		return -EOPNOTSUPP;
+	return inode->i_op->removexattr(dentry, name);
+}
+EXPORT_SYMBOL(__vfs_removexattr);
+
+int
 vfs_removexattr(struct dentry *dentry, const char *name)
 {
 	struct inode *inode = dentry->d_inode;
 	int error;
 
-	if (!inode->i_op->removexattr)
-		return -EOPNOTSUPP;
-
 	error = xattr_permission(inode, name, MAY_WRITE);
 	if (error)
 		return error;
@@ -349,7 +371,7 @@
 	if (error)
 		goto out;
 
-	error = inode->i_op->removexattr(dentry, name);
+	error = __vfs_removexattr(dentry, name);
 
 	if (!error) {
 		fsnotify_xattr(dentry);