Linux 4.4 compat: xattr operations takes xattr_handler

The xattr_hander->{list,get,set} were changed to take a xattr_handler,
and handler_flags argument was removed and should be accessed by
handler->flags.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4021

config/kernel-xattr-handler.m4

@@ -37,6 +37,11 @@ dnl # 2.6.33 API change,
 dnl # The xattr_hander->get() callback was changed to take a dentry
 dnl # instead of an inode, and a handler_flags argument was added.
 dnl #
+dnl # 4.4 API change,
+dnl # The xattr_hander->get() callback was changed to take a xattr_handler,
+dnl # and handler_flags argument was removed and should be accessed by
+dnl # handler->flags.
+dnl #
 AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_GET], [
 	AC_MSG_CHECKING([whether xattr_handler->get() wants dentry])
 	ZFS_LINUX_TRY_COMPILE([
@@ -55,6 +60,24 @@ AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_GET], [
 		    [xattr_handler->get() wants dentry])
 	],[
 		AC_MSG_RESULT(no)
+		AC_MSG_CHECKING([whether xattr_handler->get() wants xattr_handler])
+		ZFS_LINUX_TRY_COMPILE([
+			#include <linux/xattr.h>
+
+			int get(const struct xattr_handler *handler, struct dentry *dentry,
+			    const char *name, void *buffer, size_t size) { return 0; }
+			static const struct xattr_handler
+			    xops __attribute__ ((unused)) = {
+				.get = get,
+			};
+		],[
+		],[
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_HANDLER_XATTR_GET, 1,
+			    [xattr_handler->get() wants xattr_handler])
+		],[
+			AC_MSG_RESULT(no)
+		])
 	])
 ])
 
@@ -63,6 +86,11 @@ dnl # 2.6.33 API change,
 dnl # The xattr_hander->set() callback was changed to take a dentry
 dnl # instead of an inode, and a handler_flags argument was added.
 dnl #
+dnl # 4.4 API change,
+dnl # The xattr_hander->set() callback was changed to take a xattr_handler,
+dnl # and handler_flags argument was removed and should be accessed by
+dnl # handler->flags.
+dnl #
 AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_SET], [
 	AC_MSG_CHECKING([whether xattr_handler->set() wants dentry])
 	ZFS_LINUX_TRY_COMPILE([
@@ -82,6 +110,24 @@ AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_SET], [
 		    [xattr_handler->set() wants dentry])
 	],[
 		AC_MSG_RESULT(no)
+		AC_MSG_CHECKING([whether xattr_handler->set() wants xattr_handler])
+		ZFS_LINUX_TRY_COMPILE([
+			#include <linux/xattr.h>
+
+			int set(const struct xattr_handler *handler, struct dentry *dentry,
+			    const char *name, const void *buffer, size_t size, int flags) { return 0; }
+			static const struct xattr_handler
+			    xops __attribute__ ((unused)) = {
+				.set = set,
+			};
+		],[
+		],[
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_HANDLER_XATTR_SET, 1,
+			    [xattr_handler->set() wants xattr_handler])
+		],[
+			AC_MSG_RESULT(no)
+		])
 	])
 ])
 
@@ -90,6 +136,11 @@ dnl # 2.6.33 API change,
 dnl # The xattr_hander->list() callback was changed to take a dentry
 dnl # instead of an inode, and a handler_flags argument was added.
 dnl #
+dnl # 4.4 API change,
+dnl # The xattr_hander->list() callback was changed to take a xattr_handler,
+dnl # and handler_flags argument was removed and should be accessed by
+dnl # handler->flags.
+dnl #
 AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_LIST], [
 	AC_MSG_CHECKING([whether xattr_handler->list() wants dentry])
 	ZFS_LINUX_TRY_COMPILE([
@@ -109,6 +160,24 @@ AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_LIST], [
 		    [xattr_handler->list() wants dentry])
 	],[
 		AC_MSG_RESULT(no)
+		AC_MSG_CHECKING([whether xattr_handler->list() wants xattr_handler])
+		ZFS_LINUX_TRY_COMPILE([
+			#include <linux/xattr.h>
+
+			size_t list(const struct xattr_handler *handler, struct dentry *dentry,
+			    char *list, size_t list_size, const char *name, size_t name_len) { return 0; }
+			static const struct xattr_handler
+			    xops __attribute__ ((unused)) = {
+				.list = list,
+			};
+		],[
+		],[
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_HANDLER_XATTR_LIST, 1,
+			    [xattr_handler->list() wants xattr_handler])
+		],[
+			AC_MSG_RESULT(no)
+		])
 	])
 ])
 

include/linux/xattr_compat.h

@@ -54,6 +54,20 @@ fn(struct dentry *dentry, const char *name, void *buffer, size_t size,	\
 {									\
 	return (__ ## fn(dentry->d_inode, name, buffer, size));		\
 }
+/*
+ * 4.4 API change,
+ * The xattr_hander->get() callback was changed to take a xattr_handler,
+ * and handler_flags argument was removed and should be accessed by
+ * handler->flags.
+ */
+#elif defined(HAVE_HANDLER_XATTR_GET)
+#define	ZPL_XATTR_GET_WRAPPER(fn)					\
+static int								\
+fn(const struct xattr_handler *handler, struct dentry *dentry,		\
+    const char *name, void *buffer, size_t size)			\
+{									\
+	return (__ ## fn(dentry->d_inode, name, buffer, size));		\
+}
 #else
 #define	ZPL_XATTR_GET_WRAPPER(fn)					\
 static int								\
@@ -76,6 +90,20 @@ fn(struct dentry *dentry, const char *name, const void *buffer,		\
 {									\
 	return (__ ## fn(dentry->d_inode, name, buffer, size, flags));	\
 }
+/*
+ * 4.4 API change,
+ * The xattr_hander->set() callback was changed to take a xattr_handler,
+ * and handler_flags argument was removed and should be accessed by
+ * handler->flags.
+ */
+#elif defined(HAVE_HANDLER_XATTR_SET)
+#define	ZPL_XATTR_SET_WRAPPER(fn)					\
+static int								\
+fn(const struct xattr_handler *handler, struct dentry *dentry,		\
+    const char *name, const void *buffer, size_t size, int flags)	\
+{									\
+	return (__ ## fn(dentry->d_inode, name, buffer, size, flags));	\
+}
 #else
 #define	ZPL_XATTR_SET_WRAPPER(fn)					\
 static int								\

module/zfs/zpl_xattr.c

@@ -1022,6 +1022,29 @@ zpl_xattr_acl_list_default(struct dentry *dentry, char *list,
 	    list, list_size, name, name_len, type);
 }
 
+#elif defined(HAVE_HANDLER_XATTR_LIST)
+static size_t
+zpl_xattr_acl_list_access(const struct xattr_handler *handler,
+    struct dentry *dentry, char *list, size_t list_size, const char *name,
+    size_t name_len)
+{
+	int type = handler->flags;
+	ASSERT3S(type, ==, ACL_TYPE_ACCESS);
+	return zpl_xattr_acl_list(dentry->d_inode,
+	    list, list_size, name, name_len, type);
+}
+
+static size_t
+zpl_xattr_acl_list_default(const struct xattr_handler *handler,
+    struct dentry *dentry, char *list, size_t list_size, const char *name,
+    size_t name_len)
+{
+	int type = handler->flags;
+	ASSERT3S(type, ==, ACL_TYPE_DEFAULT);
+	return zpl_xattr_acl_list(dentry->d_inode,
+	    list, list_size, name, name_len, type);
+}
+
 #else
 
 static size_t
@@ -1083,6 +1106,25 @@ zpl_xattr_acl_get_default(struct dentry *dentry, const char *name,
 	return (zpl_xattr_acl_get(dentry->d_inode, name, buffer, size, type));
 }
 
+#elif defined(HAVE_HANDLER_XATTR_GET)
+static int
+zpl_xattr_acl_get_access(const struct xattr_handler *handler,
+    struct dentry *dentry, const char *name, void *buffer, size_t size)
+{
+	int type = handler->flags;
+	ASSERT3S(type, ==, ACL_TYPE_ACCESS);
+	return (zpl_xattr_acl_get(dentry->d_inode, name, buffer, size, type));
+}
+
+static int
+zpl_xattr_acl_get_default(const struct xattr_handler *handler,
+    struct dentry *dentry, const char *name, void *buffer, size_t size)
+{
+	int type = handler->flags;
+	ASSERT3S(type, ==, ACL_TYPE_DEFAULT);
+	return (zpl_xattr_acl_get(dentry->d_inode, name, buffer, size, type));
+}
+
 #else
 
 static int
@@ -1156,6 +1198,29 @@ zpl_xattr_acl_set_default(struct dentry *dentry, const char *name,
 	    name, value, size, flags, type);
 }
 
+#elif defined(HAVE_HANDLER_XATTR_SET)
+static int
+zpl_xattr_acl_set_access(const struct xattr_handler *handler,
+    struct dentry *dentry, const char *name, const void *value, size_t size,
+    int flags)
+{
+	int type = handler->flags;
+	ASSERT3S(type, ==, ACL_TYPE_ACCESS);
+	return (zpl_xattr_acl_set(dentry->d_inode,
+	    name, value, size, flags, type));
+}
+
+static int
+zpl_xattr_acl_set_default(const struct xattr_handler *handler,
+    struct dentry *dentry, const char *name, const void *value, size_t size,
+    int flags)
+{
+	int type = handler->flags;
+	ASSERT3S(type, ==, ACL_TYPE_DEFAULT);
+	return zpl_xattr_acl_set(dentry->d_inode,
+	    name, value, size, flags, type);
+}
+
 #else
 
 static int
@@ -1181,7 +1246,7 @@ struct xattr_handler zpl_xattr_acl_access_handler =
 	.list	= zpl_xattr_acl_list_access,
 	.get	= zpl_xattr_acl_get_access,
 	.set	= zpl_xattr_acl_set_access,
-#ifdef HAVE_DENTRY_XATTR_LIST
+#if defined(HAVE_DENTRY_XATTR_LIST) || defined(HAVE_HANDLER_XATTR_LIST)
 	.flags	= ACL_TYPE_ACCESS,
 #endif /* HAVE_DENTRY_XATTR_LIST */
 };
@@ -1192,7 +1257,7 @@ struct xattr_handler zpl_xattr_acl_default_handler =
 	.list	= zpl_xattr_acl_list_default,
 	.get	= zpl_xattr_acl_get_default,
 	.set	= zpl_xattr_acl_set_default,
-#ifdef HAVE_DENTRY_XATTR_LIST
+#if defined(HAVE_DENTRY_XATTR_LIST) || defined(HAVE_HANDLER_XATTR_LIST)
 	.flags	= ACL_TYPE_DEFAULT,
 #endif /* HAVE_DENTRY_XATTR_LIST */
 };