dnl #
dnl # 2.6.35 API change,
dnl # The 'struct xattr_handler' was constified in the generic
dnl # super_block structure.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_CONST_XATTR_HANDLER], [
	ZFS_LINUX_TEST_SRC([const_xattr_handler], [
		#include <linux/fs.h>
		#include <linux/xattr.h>

		const struct xattr_handler xattr_test_handler = {
			.prefix	= "test",
			.get	= NULL,
			.set	= NULL,
		};

		const struct xattr_handler *xattr_handlers[] = {
			&xattr_test_handler,
		};

		const struct super_block sb __attribute__ ((unused)) = {
			.s_xattr = xattr_handlers,
		};
	],[])
])

AC_DEFUN([ZFS_AC_KERNEL_CONST_XATTR_HANDLER], [
	AC_MSG_CHECKING([whether super_block uses const struct xattr_handler])
	ZFS_LINUX_TEST_RESULT([const_xattr_handler], [
		AC_MSG_RESULT([yes])
	],[
		ZFS_LINUX_TEST_ERROR([const xattr_handler])
	])
])

dnl #
dnl # 4.5 API change,
dnl # struct xattr_handler added new member "name".
dnl # xattr_handler which matches to whole name rather than prefix should use
dnl # "name" instead of "prefix", e.g. "system.posix_acl_access"
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_XATTR_HANDLER_NAME], [
	ZFS_LINUX_TEST_SRC([xattr_handler_name], [
		#include <linux/xattr.h>

		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.name = XATTR_NAME_POSIX_ACL_ACCESS,
		};
	],[])
])

AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_NAME], [
	AC_MSG_CHECKING([whether xattr_handler has name])
	ZFS_LINUX_TEST_RESULT([xattr_handler_name], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_XATTR_HANDLER_NAME, 1,
		    [xattr_handler has name])
	],[
		AC_MSG_RESULT(no)
	])
])

dnl #
dnl # Supported xattr handler get() interfaces checked newest to oldest.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_XATTR_HANDLER_GET], [
	ZFS_LINUX_TEST_SRC([xattr_handler_get_dentry_inode], [
		#include <linux/xattr.h>

		int get(const struct xattr_handler *handler,
		    struct dentry *dentry, struct inode *inode,
		    const char *name, void *buffer, size_t size) { return 0; }
		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.get = get,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_get_xattr_handler], [
		#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,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_get_dentry], [
		#include <linux/xattr.h>

		int get(struct dentry *dentry, const char *name,
		    void *buffer, size_t size, int handler_flags)
		    { return 0; }
		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.get = get,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_get_dentry_inode_flags], [
		#include <linux/xattr.h>

		int get(const struct xattr_handler *handler,
		    struct dentry *dentry, struct inode *inode,
		    const char *name, void *buffer,
		    size_t size, int flags) { return 0; }
		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.get = get,
		};
	],[])
])

AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_GET], [
	dnl #
	dnl # 4.7 API change,
	dnl # The xattr_handler->get() callback was changed to take both
	dnl # dentry and inode.
	dnl #
	AC_MSG_CHECKING([whether xattr_handler->get() wants dentry and inode])
	ZFS_LINUX_TEST_RESULT([xattr_handler_get_dentry_inode], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_XATTR_GET_DENTRY_INODE, 1,
		    [xattr_handler->get() wants both dentry and inode])
	],[
		dnl #
		dnl # 4.4 API change,
		dnl # The xattr_handler->get() callback was changed to take a
		dnl # attr_handler, and handler_flags argument was removed and
		dnl # should be accessed by handler->flags.
		dnl #
		AC_MSG_RESULT(no)
		AC_MSG_CHECKING(
		    [whether xattr_handler->get() wants xattr_handler])
		ZFS_LINUX_TEST_RESULT([xattr_handler_get_xattr_handler], [
			AC_MSG_RESULT(yes)
			AC_DEFINE(HAVE_XATTR_GET_HANDLER, 1,
			    [xattr_handler->get() wants xattr_handler])
		],[
			dnl #
			dnl # 2.6.33 API change,
			dnl # The xattr_handler->get() callback was changed
			dnl # to take a dentry instead of an inode, and a
			dnl # handler_flags argument was added.
			dnl #
			AC_MSG_RESULT(no)
			AC_MSG_CHECKING(
			    [whether xattr_handler->get() wants dentry])
			ZFS_LINUX_TEST_RESULT([xattr_handler_get_dentry], [
				AC_MSG_RESULT(yes)
				AC_DEFINE(HAVE_XATTR_GET_DENTRY, 1,
				    [xattr_handler->get() wants dentry])
			],[
				dnl #
				dnl # Android API change,
				dnl # The xattr_handler->get() callback was
				dnl # changed to take dentry, inode and flags.
				dnl #
				AC_MSG_RESULT(no)
				AC_MSG_CHECKING(
				    [whether xattr_handler->get() wants dentry and inode and flags])
				ZFS_LINUX_TEST_RESULT([xattr_handler_get_dentry_inode_flags], [
					AC_MSG_RESULT(yes)
					AC_DEFINE(HAVE_XATTR_GET_DENTRY_INODE_FLAGS, 1,
					    [xattr_handler->get() wants dentry and inode and flags])
				],[
					ZFS_LINUX_TEST_ERROR([xattr get()])
				])
			])
		])
	])
])

dnl #
dnl # Supported xattr handler set() interfaces checked newest to oldest.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_XATTR_HANDLER_SET], [
	ZFS_LINUX_TEST_SRC([xattr_handler_set_userns], [
		#include <linux/xattr.h>

		int set(const struct xattr_handler *handler,
			struct user_namespace *mnt_userns,
			struct dentry *dentry, struct inode *inode,
			const char *name, const void *buffer,
			size_t size, int flags)
			{ return 0; }
		static const struct xattr_handler
			xops __attribute__ ((unused)) = {
			.set = set,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_set_dentry_inode], [
		#include <linux/xattr.h>

		int set(const struct xattr_handler *handler,
		    struct dentry *dentry, struct inode *inode,
		    const char *name, const void *buffer,
		    size_t size, int flags)
		    { return 0; }
		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.set = set,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_set_xattr_handler], [
		#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,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_set_dentry], [
		#include <linux/xattr.h>

		int set(struct dentry *dentry, const char *name,
		    const void *buffer, size_t size, int flags,
		    int handler_flags) { return 0; }
		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.set = set,
		};
	],[])
])

AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_SET], [
	dnl #
	dnl # 5.12 API change,
	dnl # The xattr_handler->set() callback was changed to 8 arguments, and
	dnl # struct user_namespace* was inserted as arg #2
	dnl #
	AC_MSG_CHECKING([whether xattr_handler->set() wants dentry, inode, and user_namespace])
	ZFS_LINUX_TEST_RESULT([xattr_handler_set_userns], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_XATTR_SET_USERNS, 1,
		    [xattr_handler->set() takes user_namespace])
	],[
		dnl #
		dnl # 4.7 API change,
		dnl # The xattr_handler->set() callback was changed to take both
		dnl # dentry and inode.
		dnl #
		AC_MSG_RESULT(no)
		AC_MSG_CHECKING([whether xattr_handler->set() wants dentry and inode])
		ZFS_LINUX_TEST_RESULT([xattr_handler_set_dentry_inode], [
			AC_MSG_RESULT(yes)
			AC_DEFINE(HAVE_XATTR_SET_DENTRY_INODE, 1,
			    [xattr_handler->set() wants both dentry and inode])
		],[
			dnl #
			dnl # 4.4 API change,
			dnl # The xattr_handler->set() callback was changed to take a
			dnl # xattr_handler, and handler_flags argument was removed and
			dnl # should be accessed by handler->flags.
			dnl #
			AC_MSG_RESULT(no)
			AC_MSG_CHECKING(
			    [whether xattr_handler->set() wants xattr_handler])
			ZFS_LINUX_TEST_RESULT([xattr_handler_set_xattr_handler], [
				AC_MSG_RESULT(yes)
				AC_DEFINE(HAVE_XATTR_SET_HANDLER, 1,
				    [xattr_handler->set() wants xattr_handler])
			],[
				dnl #
				dnl # 2.6.33 API change,
				dnl # The xattr_handler->set() callback was changed
				dnl # to take a dentry instead of an inode, and a
				dnl # handler_flags argument was added.
				dnl #
				AC_MSG_RESULT(no)
				AC_MSG_CHECKING(
				    [whether xattr_handler->set() wants dentry])
				ZFS_LINUX_TEST_RESULT([xattr_handler_set_dentry], [
					AC_MSG_RESULT(yes)
					AC_DEFINE(HAVE_XATTR_SET_DENTRY, 1,
					    [xattr_handler->set() wants dentry])
				],[
					ZFS_LINUX_TEST_ERROR([xattr set()])
				])
			])
		])
	])
])

dnl #
dnl # Supported xattr handler list() interfaces checked newest to oldest.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_XATTR_HANDLER_LIST], [
	ZFS_LINUX_TEST_SRC([xattr_handler_list_simple], [
		#include <linux/xattr.h>

		bool list(struct dentry *dentry) { return 0; }
		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.list = list,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_list_xattr_handler], [
		#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,
		};
	],[])

	ZFS_LINUX_TEST_SRC([xattr_handler_list_dentry], [
		#include <linux/xattr.h>

		size_t list(struct dentry *dentry,
		    char *list, size_t list_size,
		    const char *name, size_t name_len,
		    int handler_flags) { return 0; }
		static const struct xattr_handler
		    xops __attribute__ ((unused)) = {
			.list = list,
		};
	],[])
])

AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_LIST], [
	dnl # 4.5 API change,
	dnl # The xattr_handler->list() callback was changed to take only a
	dnl # dentry and it only needs to return if it's accessible.
	AC_MSG_CHECKING([whether xattr_handler->list() wants simple])
	ZFS_LINUX_TEST_RESULT([xattr_handler_list_simple], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_XATTR_LIST_SIMPLE, 1,
		    [xattr_handler->list() wants simple])
	],[
		dnl #
		dnl # 4.4 API change,
		dnl # The xattr_handler->list() callback was changed to take a
		dnl # xattr_handler, and handler_flags argument was removed
		dnl # and should be accessed by handler->flags.
		dnl #
		AC_MSG_RESULT(no)
		AC_MSG_CHECKING(
		    [whether xattr_handler->list() wants xattr_handler])
		ZFS_LINUX_TEST_RESULT([xattr_handler_list_xattr_handler], [
			AC_MSG_RESULT(yes)
			AC_DEFINE(HAVE_XATTR_LIST_HANDLER, 1,
			    [xattr_handler->list() wants xattr_handler])
		],[
			dnl #
			dnl # 2.6.33 API change,
			dnl # The xattr_handler->list() callback was changed
			dnl # to take a dentry instead of an inode, and a
			dnl # handler_flags argument was added.
			dnl #
			AC_MSG_RESULT(no)
			AC_MSG_CHECKING(
			    [whether xattr_handler->list() wants dentry])
			ZFS_LINUX_TEST_RESULT([xattr_handler_list_dentry], [
				AC_MSG_RESULT(yes)
				AC_DEFINE(HAVE_XATTR_LIST_DENTRY, 1,
				    [xattr_handler->list() wants dentry])
			],[
				ZFS_LINUX_TEST_ERROR([xattr list()])
			])
		])
	])
])

dnl #
dnl # 3.7 API change,
dnl # The posix_acl_{from,to}_xattr functions gained a new
dnl # parameter: user_ns
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_POSIX_ACL_FROM_XATTR_USERNS], [
	ZFS_LINUX_TEST_SRC([posix_acl_from_xattr_userns], [
		#include <linux/cred.h>
		#include <linux/fs.h>
		#include <linux/posix_acl_xattr.h>
	],[
		posix_acl_from_xattr(&init_user_ns, NULL, 0);
	])
])

AC_DEFUN([ZFS_AC_KERNEL_POSIX_ACL_FROM_XATTR_USERNS], [
	AC_MSG_CHECKING([whether posix_acl_from_xattr() needs user_ns])
	ZFS_LINUX_TEST_RESULT([posix_acl_from_xattr_userns], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_POSIX_ACL_FROM_XATTR_USERNS, 1,
		    [posix_acl_from_xattr() needs user_ns])
	],[
		ZFS_LINUX_TEST_ERROR([posix_acl_from_xattr()])
	])
])

dnl #
dnl # 4.9 API change,
dnl # iops->{set,get,remove}xattr and generic_{set,get,remove}xattr are
dnl # removed. xattr operations will directly go through sb->s_xattr.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_GENERIC_SETXATTR], [
	ZFS_LINUX_TEST_SRC([have_generic_setxattr], [
		#include <linux/fs.h>
		#include <linux/xattr.h>

		static const struct inode_operations
		    iops __attribute__ ((unused)) = {
			.setxattr = generic_setxattr
		};
	],[])
])

AC_DEFUN([ZFS_AC_KERNEL_GENERIC_SETXATTR], [
	AC_MSG_CHECKING([whether generic_setxattr() exists])
	ZFS_LINUX_TEST_RESULT([have_generic_setxattr], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_GENERIC_SETXATTR, 1,
		    [generic_setxattr() exists])
	],[
		AC_MSG_RESULT(no)
	])
])

AC_DEFUN([ZFS_AC_KERNEL_SRC_XATTR], [
	ZFS_AC_KERNEL_SRC_CONST_XATTR_HANDLER
	ZFS_AC_KERNEL_SRC_XATTR_HANDLER_NAME
	ZFS_AC_KERNEL_SRC_XATTR_HANDLER_GET
	ZFS_AC_KERNEL_SRC_XATTR_HANDLER_SET
	ZFS_AC_KERNEL_SRC_XATTR_HANDLER_LIST
	ZFS_AC_KERNEL_SRC_POSIX_ACL_FROM_XATTR_USERNS
	ZFS_AC_KERNEL_SRC_GENERIC_SETXATTR
])

AC_DEFUN([ZFS_AC_KERNEL_XATTR], [
	ZFS_AC_KERNEL_CONST_XATTR_HANDLER
	ZFS_AC_KERNEL_XATTR_HANDLER_NAME
	ZFS_AC_KERNEL_XATTR_HANDLER_GET
	ZFS_AC_KERNEL_XATTR_HANDLER_SET
	ZFS_AC_KERNEL_XATTR_HANDLER_LIST
	ZFS_AC_KERNEL_POSIX_ACL_FROM_XATTR_USERNS
	ZFS_AC_KERNEL_GENERIC_SETXATTR
])