diff --git a/config/kernel-acl.m4 b/config/kernel-acl.m4
index 6e92da97d0..be08c3c607 100644
--- a/config/kernel-acl.m4
+++ b/config/kernel-acl.m4
@@ -236,7 +236,22 @@ dnl #
 dnl # 6.2 API change,
 dnl # set_acl() second paramter changed to a struct dentry *
 dnl #
+dnl # 6.3 API change,
+dnl # set_acl() first parameter changed to struct mnt_idmap *
+dnl #
 AC_DEFUN([ZFS_AC_KERNEL_SRC_INODE_OPERATIONS_SET_ACL], [
+	ZFS_LINUX_TEST_SRC([inode_operations_set_acl_mnt_idmap_dentry], [
+		#include <linux/fs.h>
+
+		int set_acl_fn(struct mnt_idmap *idmap,
+		    struct dentry *dent, struct posix_acl *acl,
+		    int type) { return 0; }
+
+		static const struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.set_acl = set_acl_fn,
+		};
+	],[])
 	ZFS_LINUX_TEST_SRC([inode_operations_set_acl_userns_dentry], [
 		#include <linux/fs.h>
 
@@ -281,17 +296,24 @@ AC_DEFUN([ZFS_AC_KERNEL_INODE_OPERATIONS_SET_ACL], [
 		AC_DEFINE(HAVE_SET_ACL, 1, [iops->set_acl() exists])
 		AC_DEFINE(HAVE_SET_ACL_USERNS, 1, [iops->set_acl() takes 4 args])
 	],[
-		ZFS_LINUX_TEST_RESULT([inode_operations_set_acl_userns_dentry], [
+		ZFS_LINUX_TEST_RESULT([inode_operations_set_acl_mnt_idmap_dentry], [
 			AC_MSG_RESULT(yes)
 			AC_DEFINE(HAVE_SET_ACL, 1, [iops->set_acl() exists])
-			AC_DEFINE(HAVE_SET_ACL_USERNS_DENTRY_ARG2, 1,
-			    [iops->set_acl() takes 4 args, arg2 is struct dentry *])
+			AC_DEFINE(HAVE_SET_ACL_IDMAP_DENTRY, 1,
+			    [iops->set_acl() takes 4 args, arg1 is struct mnt_idmap *])
 		],[
-			ZFS_LINUX_TEST_RESULT([inode_operations_set_acl], [
+			ZFS_LINUX_TEST_RESULT([inode_operations_set_acl_userns_dentry], [
 				AC_MSG_RESULT(yes)
-				AC_DEFINE(HAVE_SET_ACL, 1, [iops->set_acl() exists, takes 3 args])
+				AC_DEFINE(HAVE_SET_ACL, 1, [iops->set_acl() exists])
+				AC_DEFINE(HAVE_SET_ACL_USERNS_DENTRY_ARG2, 1,
+				    [iops->set_acl() takes 4 args, arg2 is struct dentry *])
 			],[
-				ZFS_LINUX_REQUIRE_API([i_op->set_acl()], [3.14])
+				ZFS_LINUX_TEST_RESULT([inode_operations_set_acl], [
+					AC_MSG_RESULT(yes)
+					AC_DEFINE(HAVE_SET_ACL, 1, [iops->set_acl() exists, takes 3 args])
+				],[
+					ZFS_LINUX_REQUIRE_API([i_op->set_acl()], [3.14])
+				])
 			])
 		])
 	])
diff --git a/config/kernel-generic_fillattr.m4 b/config/kernel-generic_fillattr.m4
index 0acd5d5310..02dee4d4c0 100644
--- a/config/kernel-generic_fillattr.m4
+++ b/config/kernel-generic_fillattr.m4
@@ -4,7 +4,10 @@ dnl #
 dnl # generic_fillattr in linux/fs.h now requires a struct user_namespace*
 dnl # as the first arg, to support idmapped mounts.
 dnl #
-AC_DEFUN([ZFS_AC_KERNEL_SRC_GENERIC_FILLATTR_USERNS], [
+dnl # 6.3 API
+dnl # generic_fillattr() now takes struct mnt_idmap* as the first argument
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_SRC_GENERIC_FILLATTR], [
 	ZFS_LINUX_TEST_SRC([generic_fillattr_userns], [
 		#include <linux/fs.h>
 	],[
@@ -13,16 +16,32 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_GENERIC_FILLATTR_USERNS], [
 		struct kstat *k = NULL;
 		generic_fillattr(userns, in, k);
 	])
-])
 
-AC_DEFUN([ZFS_AC_KERNEL_GENERIC_FILLATTR_USERNS], [
-	AC_MSG_CHECKING([whether generic_fillattr requires struct user_namespace*])
-	ZFS_LINUX_TEST_RESULT([generic_fillattr_userns], [
-		AC_MSG_RESULT([yes])
-		AC_DEFINE(HAVE_GENERIC_FILLATTR_USERNS, 1,
-		    [generic_fillattr requires struct user_namespace*])
+	ZFS_LINUX_TEST_SRC([generic_fillattr_mnt_idmap], [
+		#include <linux/fs.h>
 	],[
-		AC_MSG_RESULT([no])
+		struct mnt_idmap *idmap = NULL;
+		struct inode *in = NULL;
+		struct kstat *k = NULL;
+		generic_fillattr(idmap, in, k);
+	])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_GENERIC_FILLATTR], [
+	AC_MSG_CHECKING([whether generic_fillattr requires struct mnt_idmap*])
+	ZFS_LINUX_TEST_RESULT([generic_fillattr_mnt_idmap], [
+		AC_MSG_RESULT([yes])
+		AC_DEFINE(HAVE_GENERIC_FILLATTR_IDMAP, 1,
+		    [generic_fillattr requires struct mnt_idmap*])
+	],[
+		AC_MSG_CHECKING([whether generic_fillattr requires struct user_namespace*])
+		ZFS_LINUX_TEST_RESULT([generic_fillattr_userns], [
+			AC_MSG_RESULT([yes])
+			AC_DEFINE(HAVE_GENERIC_FILLATTR_USERNS, 1,
+			    [generic_fillattr requires struct user_namespace*])
+		],[
+			AC_MSG_RESULT([no])
+		])
 	])
 ])
 
diff --git a/config/kernel-inode-create.m4 b/config/kernel-inode-create.m4
index a6ea11fb61..9e9e431809 100644
--- a/config/kernel-inode-create.m4
+++ b/config/kernel-inode-create.m4
@@ -1,4 +1,22 @@
 AC_DEFUN([ZFS_AC_KERNEL_SRC_CREATE], [
+	dnl #
+	dnl # 6.3 API change
+	dnl # The first arg is changed to struct mnt_idmap *
+	dnl #
+	ZFS_LINUX_TEST_SRC([create_mnt_idmap], [
+		#include <linux/fs.h>
+		#include <linux/sched.h>
+
+		int inode_create(struct mnt_idmap *idmap,
+		    struct inode *inode ,struct dentry *dentry,
+		    umode_t umode, bool flag) { return 0; }
+
+		static const struct inode_operations
+			iops __attribute__ ((unused)) = {
+			.create         = inode_create,
+		};
+	],[])
+
 	dnl #
 	dnl # 5.12 API change that added the struct user_namespace* arg
 	dnl # to the front of this function type's arg list.
@@ -35,19 +53,28 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_CREATE], [
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_CREATE], [
-	AC_MSG_CHECKING([whether iops->create() takes struct user_namespace*])
-	ZFS_LINUX_TEST_RESULT([create_userns], [
+	AC_MSG_CHECKING([whether iops->create() takes struct mnt_idmap*])
+	ZFS_LINUX_TEST_RESULT([create_mnt_idmap], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_IOPS_CREATE_USERNS, 1,
-		   [iops->create() takes struct user_namespace*])
+		AC_DEFINE(HAVE_IOPS_CREATE_IDMAP, 1,
+		   [iops->create() takes struct mnt_idmap*])
 	],[
 		AC_MSG_RESULT(no)
 
-		AC_MSG_CHECKING([whether iops->create() passes flags])
-		ZFS_LINUX_TEST_RESULT([create_flags], [
+		AC_MSG_CHECKING([whether iops->create() takes struct user_namespace*])
+		ZFS_LINUX_TEST_RESULT([create_userns], [
 			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_IOPS_CREATE_USERNS, 1,
+			   [iops->create() takes struct user_namespace*])
 		],[
-			ZFS_LINUX_TEST_ERROR([iops->create()])
+			AC_MSG_RESULT(no)
+
+			AC_MSG_CHECKING([whether iops->create() passes flags])
+			ZFS_LINUX_TEST_RESULT([create_flags], [
+				AC_MSG_RESULT(yes)
+			],[
+				ZFS_LINUX_TEST_ERROR([iops->create()])
+			])
 		])
 	])
 ])
diff --git a/config/kernel-inode-getattr.m4 b/config/kernel-inode-getattr.m4
index f62e82f523..c8bfb07862 100644
--- a/config/kernel-inode-getattr.m4
+++ b/config/kernel-inode-getattr.m4
@@ -1,4 +1,24 @@
 AC_DEFUN([ZFS_AC_KERNEL_SRC_INODE_GETATTR], [
+	dnl #
+	dnl # Linux 6.3 API
+	dnl # The first arg of getattr I/O operations handler type
+	dnl # is changed to struct mnt_idmap*
+	dnl #
+	ZFS_LINUX_TEST_SRC([inode_operations_getattr_mnt_idmap], [
+		#include <linux/fs.h>
+
+		int test_getattr(
+		    struct mnt_idmap *idmap,
+		    const struct path *p, struct kstat *k,
+		    u32 request_mask, unsigned int query_flags)
+		    { return 0; }
+
+		static const struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.getattr = test_getattr,
+		};
+	],[])
+
 	dnl #
 	dnl # Linux 5.12 API
 	dnl # The getattr I/O operations handler type was extended to require
@@ -55,37 +75,48 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_INODE_GETATTR], [
 
 AC_DEFUN([ZFS_AC_KERNEL_INODE_GETATTR], [
 	dnl #
-	dnl # Kernel 5.12 test
+	dnl # Kernel 6.3 test
 	dnl #
-	AC_MSG_CHECKING([whether iops->getattr() takes user_namespace])
-	ZFS_LINUX_TEST_RESULT([inode_operations_getattr_userns], [
+	AC_MSG_CHECKING([whether iops->getattr() takes mnt_idmap])
+	ZFS_LINUX_TEST_RESULT([inode_operations_getattr_mnt_idmap], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_USERNS_IOPS_GETATTR, 1,
-		    [iops->getattr() takes struct user_namespace*])
+		AC_DEFINE(HAVE_IDMAP_IOPS_GETATTR, 1,
+		    [iops->getattr() takes struct mnt_idmap*])
 	],[
 		AC_MSG_RESULT(no)
-
 		dnl #
-		dnl # Kernel 4.11 test
+		dnl # Kernel 5.12 test
 		dnl #
-		AC_MSG_CHECKING([whether iops->getattr() takes a path])
-		ZFS_LINUX_TEST_RESULT([inode_operations_getattr_path], [
+		AC_MSG_CHECKING([whether iops->getattr() takes user_namespace])
+		ZFS_LINUX_TEST_RESULT([inode_operations_getattr_userns], [
 			AC_MSG_RESULT(yes)
-			AC_DEFINE(HAVE_PATH_IOPS_GETATTR, 1,
-				[iops->getattr() takes a path])
+			AC_DEFINE(HAVE_USERNS_IOPS_GETATTR, 1,
+			    [iops->getattr() takes struct user_namespace*])
 		],[
 			AC_MSG_RESULT(no)
 
 			dnl #
-			dnl # Kernel < 4.11 test
+			dnl # Kernel 4.11 test
 			dnl #
-			AC_MSG_CHECKING([whether iops->getattr() takes a vfsmount])
-			ZFS_LINUX_TEST_RESULT([inode_operations_getattr_vfsmount], [
+			AC_MSG_CHECKING([whether iops->getattr() takes a path])
+			ZFS_LINUX_TEST_RESULT([inode_operations_getattr_path], [
 				AC_MSG_RESULT(yes)
-				AC_DEFINE(HAVE_VFSMOUNT_IOPS_GETATTR, 1,
-					[iops->getattr() takes a vfsmount])
+				AC_DEFINE(HAVE_PATH_IOPS_GETATTR, 1,
+					[iops->getattr() takes a path])
 			],[
 				AC_MSG_RESULT(no)
+
+				dnl #
+				dnl # Kernel < 4.11 test
+				dnl #
+				AC_MSG_CHECKING([whether iops->getattr() takes a vfsmount])
+				ZFS_LINUX_TEST_RESULT([inode_operations_getattr_vfsmount], [
+					AC_MSG_RESULT(yes)
+					AC_DEFINE(HAVE_VFSMOUNT_IOPS_GETATTR, 1,
+						[iops->getattr() takes a vfsmount])
+				],[
+					AC_MSG_RESULT(no)
+				])
 			])
 		])
 	])
diff --git a/config/kernel-inode-setattr.m4 b/config/kernel-inode-setattr.m4
new file mode 100644
index 0000000000..45755b4eb2
--- /dev/null
+++ b/config/kernel-inode-setattr.m4
@@ -0,0 +1,87 @@
+AC_DEFUN([ZFS_AC_KERNEL_SRC_INODE_SETATTR], [
+	dnl #
+	dnl # Linux 6.3 API
+	dnl # The first arg of setattr I/O operations handler type
+	dnl # is changed to struct mnt_idmap*
+	dnl #
+	ZFS_LINUX_TEST_SRC([inode_operations_setattr_mnt_idmap], [
+		#include <linux/fs.h>
+
+		int test_setattr(
+		    struct mnt_idmap *idmap,
+		    struct dentry *de, struct iattr *ia)
+		    { return 0; }
+
+		static const struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.setattr = test_setattr,
+		};
+	],[])
+
+	dnl #
+	dnl # Linux 5.12 API
+	dnl # The setattr I/O operations handler type was extended to require
+	dnl # a struct user_namespace* as its first arg, to support idmapped
+	dnl # mounts.
+	dnl #
+	ZFS_LINUX_TEST_SRC([inode_operations_setattr_userns], [
+		#include <linux/fs.h>
+
+		int test_setattr(
+		    struct user_namespace *userns,
+		    struct dentry *de, struct iattr *ia)
+		    { return 0; }
+
+		static const struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.setattr = test_setattr,
+		};
+	],[])
+
+	ZFS_LINUX_TEST_SRC([inode_operations_setattr], [
+		#include <linux/fs.h>
+
+		int test_setattr(
+		    struct dentry *de, struct iattr *ia)
+		    { return 0; }
+
+		static const struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.setattr = test_setattr,
+		};
+	],[])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_INODE_SETATTR], [
+	dnl #
+	dnl # Kernel 6.3 test
+	dnl #
+	AC_MSG_CHECKING([whether iops->setattr() takes mnt_idmap])
+	ZFS_LINUX_TEST_RESULT([inode_operations_setattr_mnt_idmap], [
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_IDMAP_IOPS_SETATTR, 1,
+		    [iops->setattr() takes struct mnt_idmap*])
+	],[
+		AC_MSG_RESULT(no)
+		dnl #
+		dnl # Kernel 5.12 test
+		dnl #
+		AC_MSG_CHECKING([whether iops->setattr() takes user_namespace])
+		ZFS_LINUX_TEST_RESULT([inode_operations_setattr_userns], [
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_USERNS_IOPS_SETATTR, 1,
+			    [iops->setattr() takes struct user_namespace*])
+		],[
+			AC_MSG_RESULT(no)
+
+			AC_MSG_CHECKING([whether iops->setattr() exists])
+			ZFS_LINUX_TEST_RESULT([inode_operations_setattr], [
+				AC_MSG_RESULT(yes)
+				AC_DEFINE(HAVE_IOPS_SETATTR, 1,
+					[iops->setattr() exists])
+			],[
+				AC_MSG_RESULT(no)
+			])
+		])
+	])
+])
diff --git a/config/kernel-is_owner_or_cap.m4 b/config/kernel-is_owner_or_cap.m4
index a90cf3da64..4e9c002b77 100644
--- a/config/kernel-is_owner_or_cap.m4
+++ b/config/kernel-is_owner_or_cap.m4
@@ -16,12 +16,20 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_INODE_OWNER_OR_CAPABLE], [
 		(void) inode_owner_or_capable(ip);
 	])
 
-	ZFS_LINUX_TEST_SRC([inode_owner_or_capable_idmapped], [
+	ZFS_LINUX_TEST_SRC([inode_owner_or_capable_userns], [
 		#include <linux/fs.h>
 	],[
 		struct inode *ip = NULL;
 		(void) inode_owner_or_capable(&init_user_ns, ip);
 	])
+
+	ZFS_LINUX_TEST_SRC([inode_owner_or_capable_mnt_idmap], [
+		#include <linux/fs.h>
+		#include <linux/mnt_idmapping.h>
+	],[
+		struct inode *ip = NULL;
+		(void) inode_owner_or_capable(&nop_mnt_idmap, ip);
+	])
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_INODE_OWNER_OR_CAPABLE], [
@@ -35,12 +43,21 @@ AC_DEFUN([ZFS_AC_KERNEL_INODE_OWNER_OR_CAPABLE], [
 
 		AC_MSG_CHECKING(
 		    [whether inode_owner_or_capable() takes user_ns])
-		ZFS_LINUX_TEST_RESULT([inode_owner_or_capable_idmapped], [
+		ZFS_LINUX_TEST_RESULT([inode_owner_or_capable_userns], [
 			AC_MSG_RESULT(yes)
-			AC_DEFINE(HAVE_INODE_OWNER_OR_CAPABLE_IDMAPPED, 1,
+			AC_DEFINE(HAVE_INODE_OWNER_OR_CAPABLE_USERNS, 1,
 			    [inode_owner_or_capable() takes user_ns])
 		],[
-			ZFS_LINUX_TEST_ERROR([capability])
+			AC_MSG_RESULT(no)
+			AC_MSG_CHECKING(
+			    [whether inode_owner_or_capable() takes mnt_idmap])
+			ZFS_LINUX_TEST_RESULT([inode_owner_or_capable_mnt_idmap], [
+				AC_MSG_RESULT(yes)
+				AC_DEFINE(HAVE_INODE_OWNER_OR_CAPABLE_IDMAP, 1,
+				    [inode_owner_or_capable() takes mnt_idmap])
+			], [
+				ZFS_LINUX_TEST_ERROR([capability])
+			])
 		])
 	])
 ])
diff --git a/config/kernel-mkdir.m4 b/config/kernel-mkdir.m4
index 6667ed04fa..7407a791b8 100644
--- a/config/kernel-mkdir.m4
+++ b/config/kernel-mkdir.m4
@@ -2,6 +2,22 @@ dnl #
 dnl # Supported mkdir() interfaces checked newest to oldest.
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_SRC_MKDIR], [
+	dnl #
+	dnl # 6.3 API change
+	dnl # mkdir() takes struct mnt_idmap * as the first arg
+	dnl #
+	ZFS_LINUX_TEST_SRC([mkdir_mnt_idmap], [
+		#include <linux/fs.h>
+
+		int mkdir(struct mnt_idmap *idmap,
+			struct inode *inode, struct dentry *dentry,
+			umode_t umode) { return 0; }
+		static const struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.mkdir = mkdir,
+		};
+	],[])
+
 	dnl #
 	dnl # 5.12 API change
 	dnl # The struct user_namespace arg was added as the first argument to
@@ -43,25 +59,36 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_MKDIR], [
 
 AC_DEFUN([ZFS_AC_KERNEL_MKDIR], [
 	dnl #
-	dnl # 5.12 API change
-	dnl # The struct user_namespace arg was added as the first argument to
-	dnl # mkdir() of the iops structure.
+	dnl # 6.3 API change
+	dnl # mkdir() takes struct mnt_idmap * as the first arg
 	dnl #
-	AC_MSG_CHECKING([whether iops->mkdir() takes struct user_namespace*])
-	ZFS_LINUX_TEST_RESULT([mkdir_user_namespace], [
+	AC_MSG_CHECKING([whether iops->mkdir() takes struct mnt_idmap*])
+	ZFS_LINUX_TEST_RESULT([mkdir_mnt_idmap], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_IOPS_MKDIR_USERNS, 1,
-		    [iops->mkdir() takes struct user_namespace*])
+		AC_DEFINE(HAVE_IOPS_MKDIR_IDMAP, 1,
+		    [iops->mkdir() takes struct mnt_idmap*])
 	],[
-		AC_MSG_RESULT(no)
-
-		AC_MSG_CHECKING([whether iops->mkdir() takes umode_t])
-		ZFS_LINUX_TEST_RESULT([inode_operations_mkdir], [
+		dnl #
+		dnl # 5.12 API change
+		dnl # The struct user_namespace arg was added as the first argument to
+		dnl # mkdir() of the iops structure.
+		dnl #
+		AC_MSG_CHECKING([whether iops->mkdir() takes struct user_namespace*])
+		ZFS_LINUX_TEST_RESULT([mkdir_user_namespace], [
 			AC_MSG_RESULT(yes)
-			AC_DEFINE(HAVE_MKDIR_UMODE_T, 1,
-			    [iops->mkdir() takes umode_t])
+			AC_DEFINE(HAVE_IOPS_MKDIR_USERNS, 1,
+			    [iops->mkdir() takes struct user_namespace*])
 		],[
-			ZFS_LINUX_TEST_ERROR([mkdir()])
+			AC_MSG_RESULT(no)
+
+			AC_MSG_CHECKING([whether iops->mkdir() takes umode_t])
+			ZFS_LINUX_TEST_RESULT([inode_operations_mkdir], [
+				AC_MSG_RESULT(yes)
+				AC_DEFINE(HAVE_MKDIR_UMODE_T, 1,
+				    [iops->mkdir() takes umode_t])
+			],[
+				ZFS_LINUX_TEST_ERROR([mkdir()])
+			])
 		])
 	])
 ])
diff --git a/config/kernel-mknod.m4 b/config/kernel-mknod.m4
index ffe4510600..1494ec1ae4 100644
--- a/config/kernel-mknod.m4
+++ b/config/kernel-mknod.m4
@@ -1,4 +1,22 @@
 AC_DEFUN([ZFS_AC_KERNEL_SRC_MKNOD], [
+	dnl #
+	dnl # 6.3 API change
+	dnl # The first arg is now struct mnt_idmap*
+	dnl #
+	ZFS_LINUX_TEST_SRC([mknod_mnt_idmap], [
+		#include <linux/fs.h>
+		#include <linux/sched.h>
+
+		int tmp_mknod(struct mnt_idmap *idmap,
+		    struct inode *inode ,struct dentry *dentry,
+		    umode_t u, dev_t d) { return 0; }
+
+		static const struct inode_operations
+			iops __attribute__ ((unused)) = {
+			.mknod          = tmp_mknod,
+		};
+	],[])
+
 	dnl #
 	dnl # 5.12 API change that added the struct user_namespace* arg
 	dnl # to the front of this function type's arg list.
@@ -19,12 +37,20 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_MKNOD], [
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_MKNOD], [
-	AC_MSG_CHECKING([whether iops->mknod() takes struct user_namespace*])
-	ZFS_LINUX_TEST_RESULT([mknod_userns], [
+	AC_MSG_CHECKING([whether iops->mknod() takes struct mnt_idmap*])
+	ZFS_LINUX_TEST_RESULT([mknod_mnt_idmap], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_IOPS_MKNOD_USERNS, 1,
-		    [iops->mknod() takes struct user_namespace*])
+		AC_DEFINE(HAVE_IOPS_MKNOD_IDMAP, 1,
+		    [iops->mknod() takes struct mnt_idmap*])
 	],[
 		AC_MSG_RESULT(no)
+		AC_MSG_CHECKING([whether iops->mknod() takes struct user_namespace*])
+		ZFS_LINUX_TEST_RESULT([mknod_userns], [
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_IOPS_MKNOD_USERNS, 1,
+			    [iops->mknod() takes struct user_namespace*])
+		],[
+			AC_MSG_RESULT(no)
+		])
 	])
 ])
diff --git a/config/kernel-rename.m4 b/config/kernel-rename.m4
index 302db43f57..b33cd0bfb0 100644
--- a/config/kernel-rename.m4
+++ b/config/kernel-rename.m4
@@ -33,24 +33,48 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_RENAME], [
 			.rename = rename_fn,
 		};
 	],[])
+
+	dnl #
+	dnl # 6.3 API change - the first arg is now struct mnt_idmap*
+	dnl #
+	ZFS_LINUX_TEST_SRC([inode_operations_rename_mnt_idmap], [
+		#include <linux/fs.h>
+		int rename_fn(struct mnt_idmap *idmap, struct inode *sip,
+			struct dentry *sdp, struct inode *tip, struct dentry *tdp,
+			unsigned int flags) { return 0; }
+
+		static const struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.rename = rename_fn,
+		};
+	],[])
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_RENAME], [
-	AC_MSG_CHECKING([whether iops->rename() takes struct user_namespace*])
-	ZFS_LINUX_TEST_RESULT([inode_operations_rename_userns], [
+	AC_MSG_CHECKING([whether iops->rename() takes struct mnt_idmap*])
+	ZFS_LINUX_TEST_RESULT([inode_operations_rename_mnt_idmap], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_IOPS_RENAME_USERNS, 1,
-		    [iops->rename() takes struct user_namespace*])
+		AC_DEFINE(HAVE_IOPS_RENAME_IDMAP, 1,
+		    [iops->rename() takes struct mnt_idmap*])
 	],[
 		AC_MSG_RESULT(no)
 
-		AC_MSG_CHECKING([whether iop->rename() wants flags])
-		ZFS_LINUX_TEST_RESULT([inode_operations_rename_flags], [
+		AC_MSG_CHECKING([whether iops->rename() takes struct user_namespace*])
+		ZFS_LINUX_TEST_RESULT([inode_operations_rename_userns], [
 			AC_MSG_RESULT(yes)
-			AC_DEFINE(HAVE_RENAME_WANTS_FLAGS, 1,
-				[iops->rename() wants flags])
+			AC_DEFINE(HAVE_IOPS_RENAME_USERNS, 1,
+			    [iops->rename() takes struct user_namespace*])
 		],[
 			AC_MSG_RESULT(no)
+
+			AC_MSG_CHECKING([whether iops->rename() wants flags])
+			ZFS_LINUX_TEST_RESULT([inode_operations_rename_flags], [
+				AC_MSG_RESULT(yes)
+				AC_DEFINE(HAVE_RENAME_WANTS_FLAGS, 1,
+					[iops->rename() wants flags])
+			],[
+				AC_MSG_RESULT(no)
+			])
 		])
 	])
 ])
diff --git a/config/kernel-setattr-prepare.m4 b/config/kernel-setattr-prepare.m4
index 24245aa534..e02d6263e9 100644
--- a/config/kernel-setattr-prepare.m4
+++ b/config/kernel-setattr-prepare.m4
@@ -27,26 +27,48 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_SETATTR_PREPARE], [
 		int error __attribute__ ((unused)) =
 			setattr_prepare(userns, dentry, attr);
 	])
+
+	dnl #
+	dnl # 6.3 API change
+	dnl # The first arg of setattr_prepare() is changed to struct mnt_idmap*
+	dnl #
+	ZFS_LINUX_TEST_SRC([setattr_prepare_mnt_idmap], [
+		#include <linux/fs.h>
+	], [
+		struct dentry *dentry = NULL;
+		struct iattr *attr = NULL;
+		struct mnt_idmap *idmap = NULL;
+		int error __attribute__ ((unused)) =
+			setattr_prepare(idmap, dentry, attr);
+	])
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_SETATTR_PREPARE], [
-	AC_MSG_CHECKING([whether setattr_prepare() is available and accepts struct user_namespace*])
-	ZFS_LINUX_TEST_RESULT_SYMBOL([setattr_prepare_userns],
+	AC_MSG_CHECKING([whether setattr_prepare() is available and accepts struct mnt_idmap*])
+	ZFS_LINUX_TEST_RESULT_SYMBOL([setattr_prepare_mnt_idmap],
 	    [setattr_prepare], [fs/attr.c], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_SETATTR_PREPARE_USERNS, 1,
-		    [setattr_prepare() accepts user_namespace])
+		AC_DEFINE(HAVE_SETATTR_PREPARE_IDMAP, 1,
+		    [setattr_prepare() accepts mnt_idmap])
 	], [
-		AC_MSG_RESULT(no)
-
-		AC_MSG_CHECKING([whether setattr_prepare() is available, doesn't accept user_namespace])
-		ZFS_LINUX_TEST_RESULT_SYMBOL([setattr_prepare],
-			[setattr_prepare], [fs/attr.c], [
+		AC_MSG_CHECKING([whether setattr_prepare() is available and accepts struct user_namespace*])
+		ZFS_LINUX_TEST_RESULT_SYMBOL([setattr_prepare_userns],
+		    [setattr_prepare], [fs/attr.c], [
 			AC_MSG_RESULT(yes)
-			AC_DEFINE(HAVE_SETATTR_PREPARE_NO_USERNS, 1,
-				[setattr_prepare() is available, doesn't accept user_namespace])
+			AC_DEFINE(HAVE_SETATTR_PREPARE_USERNS, 1,
+			    [setattr_prepare() accepts user_namespace])
 		], [
 			AC_MSG_RESULT(no)
+
+			AC_MSG_CHECKING([whether setattr_prepare() is available, doesn't accept user_namespace])
+			ZFS_LINUX_TEST_RESULT_SYMBOL([setattr_prepare],
+				[setattr_prepare], [fs/attr.c], [
+				AC_MSG_RESULT(yes)
+				AC_DEFINE(HAVE_SETATTR_PREPARE_NO_USERNS, 1,
+					[setattr_prepare() is available, doesn't accept user_namespace])
+			], [
+				AC_MSG_RESULT(no)
+			])
 		])
 	])
 ])
diff --git a/config/kernel-symlink.m4 b/config/kernel-symlink.m4
index d90366d04b..a0333ed66a 100644
--- a/config/kernel-symlink.m4
+++ b/config/kernel-symlink.m4
@@ -1,4 +1,20 @@
 AC_DEFUN([ZFS_AC_KERNEL_SRC_SYMLINK], [
+	dnl #
+	dnl # 6.3 API change that changed the first arg
+	dnl # to struct mnt_idmap*
+	dnl #
+	ZFS_LINUX_TEST_SRC([symlink_mnt_idmap], [
+		#include <linux/fs.h>
+		#include <linux/sched.h>
+		int tmp_symlink(struct mnt_idmap *idmap,
+		    struct inode *inode ,struct dentry *dentry,
+		    const char *path) { return 0; }
+
+		static const struct inode_operations
+			iops __attribute__ ((unused)) = {
+			.symlink                = tmp_symlink,
+		};
+	],[])
 	dnl #
 	dnl # 5.12 API change that added the struct user_namespace* arg
 	dnl # to the front of this function type's arg list.
@@ -19,12 +35,19 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_SYMLINK], [
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_SYMLINK], [
-	AC_MSG_CHECKING([whether iops->symlink() takes struct user_namespace*])
-	ZFS_LINUX_TEST_RESULT([symlink_userns], [
+	AC_MSG_CHECKING([whether iops->symlink() takes struct mnt_idmap*])
+	ZFS_LINUX_TEST_RESULT([symlink_mnt_idmap], [
 		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_IOPS_SYMLINK_USERNS, 1,
-		    [iops->symlink() takes struct user_namespace*])
+		AC_DEFINE(HAVE_IOPS_SYMLINK_IDMAP, 1,
+		    [iops->symlink() takes struct mnt_idmap*])
 	],[
-		AC_MSG_RESULT(no)
+		AC_MSG_CHECKING([whether iops->symlink() takes struct user_namespace*])
+		ZFS_LINUX_TEST_RESULT([symlink_userns], [
+			AC_MSG_RESULT(yes)
+			AC_DEFINE(HAVE_IOPS_SYMLINK_USERNS, 1,
+			    [iops->symlink() takes struct user_namespace*])
+		],[
+			AC_MSG_RESULT(no)
+		])
 	])
 ])
diff --git a/config/kernel-tmpfile.m4 b/config/kernel-tmpfile.m4
index 0e1deb3612..cc18b8f65a 100644
--- a/config/kernel-tmpfile.m4
+++ b/config/kernel-tmpfile.m4
@@ -4,6 +4,19 @@ dnl # Add support for i_op->tmpfile
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_SRC_TMPFILE], [
 	dnl #
+	dnl # 6.3 API change
+	dnl # The first arg is now struct mnt_idmap * 
+	dnl #
+	ZFS_LINUX_TEST_SRC([inode_operations_tmpfile_mnt_idmap], [
+		#include <linux/fs.h>
+		int tmpfile(struct mnt_idmap *idmap,
+		    struct inode *inode, struct file *file,
+		    umode_t mode) { return 0; }
+		static struct inode_operations
+		    iops __attribute__ ((unused)) = {
+			.tmpfile = tmpfile,
+		};
+	],[])
 	dnl # 6.1 API change
 	dnl # use struct file instead of struct dentry
 	dnl #
@@ -44,23 +57,29 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_TMPFILE], [
 
 AC_DEFUN([ZFS_AC_KERNEL_TMPFILE], [
 	AC_MSG_CHECKING([whether i_op->tmpfile() exists])
-	ZFS_LINUX_TEST_RESULT([inode_operations_tmpfile], [
+	ZFS_LINUX_TEST_RESULT([inode_operations_tmpfile_mnt_idmap], [
 		AC_MSG_RESULT(yes)
 		AC_DEFINE(HAVE_TMPFILE, 1, [i_op->tmpfile() exists])
-		AC_DEFINE(HAVE_TMPFILE_USERNS, 1, [i_op->tmpfile() has userns])
-	],[
-		ZFS_LINUX_TEST_RESULT([inode_operations_tmpfile_dentry_userns], [
+		AC_DEFINE(HAVE_TMPFILE_IDMAP, 1, [i_op->tmpfile() has mnt_idmap])
+	], [
+		ZFS_LINUX_TEST_RESULT([inode_operations_tmpfile], [
 			AC_MSG_RESULT(yes)
 			AC_DEFINE(HAVE_TMPFILE, 1, [i_op->tmpfile() exists])
 			AC_DEFINE(HAVE_TMPFILE_USERNS, 1, [i_op->tmpfile() has userns])
-			AC_DEFINE(HAVE_TMPFILE_DENTRY, 1, [i_op->tmpfile() uses old dentry signature])
 		],[
-			ZFS_LINUX_TEST_RESULT([inode_operations_tmpfile_dentry], [
+			ZFS_LINUX_TEST_RESULT([inode_operations_tmpfile_dentry_userns], [
 				AC_MSG_RESULT(yes)
 				AC_DEFINE(HAVE_TMPFILE, 1, [i_op->tmpfile() exists])
+				AC_DEFINE(HAVE_TMPFILE_USERNS, 1, [i_op->tmpfile() has userns])
 				AC_DEFINE(HAVE_TMPFILE_DENTRY, 1, [i_op->tmpfile() uses old dentry signature])
 			],[
-				ZFS_LINUX_REQUIRE_API([i_op->tmpfile()], [3.11])
+				ZFS_LINUX_TEST_RESULT([inode_operations_tmpfile_dentry], [
+					AC_MSG_RESULT(yes)
+					AC_DEFINE(HAVE_TMPFILE, 1, [i_op->tmpfile() exists])
+					AC_DEFINE(HAVE_TMPFILE_DENTRY, 1, [i_op->tmpfile() uses old dentry signature])
+				],[
+					ZFS_LINUX_REQUIRE_API([i_op->tmpfile()], [3.11])
+				])
 			])
 		])
 	])
diff --git a/config/kernel-xattr-handler.m4 b/config/kernel-xattr-handler.m4
index b6cbfa1550..6b8a08dbcc 100644
--- a/config/kernel-xattr-handler.m4
+++ b/config/kernel-xattr-handler.m4
@@ -179,6 +179,21 @@ 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_mnt_idmap], [
+		#include <linux/xattr.h>
+
+		int set(const struct xattr_handler *handler,
+			struct mnt_idmap *idmap,
+			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_userns], [
 		#include <linux/xattr.h>
 
@@ -240,53 +255,63 @@ AC_DEFUN([ZFS_AC_KERNEL_XATTR_HANDLER_SET], [
 	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], [
+	dnl # 6.3 API change,
+	dnl # The xattr_handler->set() callback 2nd arg is now struct mnt_idmap *
+	dnl #
+	AC_MSG_CHECKING([whether xattr_handler->set() wants dentry, inode, and mnt_idmap])
+	ZFS_LINUX_TEST_RESULT([xattr_handler_set_mnt_idmap], [
 		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_DEFINE(HAVE_XATTR_SET_IDMAP, 1,
+		    [xattr_handler->set() takes mnt_idmap])
+	], [
+		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_DENTRY_INODE, 1,
-			    [xattr_handler->set() wants both dentry and inode])
+			AC_DEFINE(HAVE_XATTR_SET_USERNS, 1,
+			    [xattr_handler->set() takes user_namespace])
 		],[
 			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 # 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 xattr_handler])
-			ZFS_LINUX_TEST_RESULT([xattr_handler_set_xattr_handler], [
+			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_HANDLER, 1,
-				    [xattr_handler->set() wants xattr_handler])
+				AC_DEFINE(HAVE_XATTR_SET_DENTRY_INODE, 1,
+				    [xattr_handler->set() wants both dentry and inode])
 			],[
 				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 # 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 dentry])
-				ZFS_LINUX_TEST_RESULT([xattr_handler_set_dentry], [
+				    [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_DENTRY, 1,
-					    [xattr_handler->set() wants dentry])
+					AC_DEFINE(HAVE_XATTR_SET_HANDLER, 1,
+					    [xattr_handler->set() wants xattr_handler])
 				],[
-					ZFS_LINUX_TEST_ERROR([xattr set()])
+					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()])
+					])
 				])
 			])
 		])
diff --git a/config/kernel.m4 b/config/kernel.m4
index b0aff47485..f754e039c1 100644
--- a/config/kernel.m4
+++ b/config/kernel.m4
@@ -69,6 +69,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_SRC], [
 	ZFS_AC_KERNEL_SRC_INODE_OWNER_OR_CAPABLE
 	ZFS_AC_KERNEL_SRC_XATTR
 	ZFS_AC_KERNEL_SRC_ACL
+	ZFS_AC_KERNEL_SRC_INODE_SETATTR
 	ZFS_AC_KERNEL_SRC_INODE_GETATTR
 	ZFS_AC_KERNEL_SRC_INODE_SET_FLAGS
 	ZFS_AC_KERNEL_SRC_INODE_SET_IVERSION
@@ -130,7 +131,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_SRC], [
 	ZFS_AC_KERNEL_SRC_KSTRTOUL
 	ZFS_AC_KERNEL_SRC_PERCPU
 	ZFS_AC_KERNEL_SRC_CPU_HOTPLUG
-	ZFS_AC_KERNEL_SRC_GENERIC_FILLATTR_USERNS
+	ZFS_AC_KERNEL_SRC_GENERIC_FILLATTR
 	ZFS_AC_KERNEL_SRC_MKNOD
 	ZFS_AC_KERNEL_SRC_SYMLINK
 	ZFS_AC_KERNEL_SRC_BIO_MAX_SEGS
@@ -194,6 +195,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_RESULT], [
 	ZFS_AC_KERNEL_INODE_OWNER_OR_CAPABLE
 	ZFS_AC_KERNEL_XATTR
 	ZFS_AC_KERNEL_ACL
+	ZFS_AC_KERNEL_INODE_SETATTR
 	ZFS_AC_KERNEL_INODE_GETATTR
 	ZFS_AC_KERNEL_INODE_SET_FLAGS
 	ZFS_AC_KERNEL_INODE_SET_IVERSION
@@ -255,7 +257,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_RESULT], [
 	ZFS_AC_KERNEL_KSTRTOUL
 	ZFS_AC_KERNEL_PERCPU
 	ZFS_AC_KERNEL_CPU_HOTPLUG
-	ZFS_AC_KERNEL_GENERIC_FILLATTR_USERNS
+	ZFS_AC_KERNEL_GENERIC_FILLATTR
 	ZFS_AC_KERNEL_MKNOD
 	ZFS_AC_KERNEL_SYMLINK
 	ZFS_AC_KERNEL_BIO_MAX_SEGS
diff --git a/include/os/linux/kernel/linux/vfs_compat.h b/include/os/linux/kernel/linux/vfs_compat.h
index 91e908598f..e82bbf755d 100644
--- a/include/os/linux/kernel/linux/vfs_compat.h
+++ b/include/os/linux/kernel/linux/vfs_compat.h
@@ -344,7 +344,8 @@ static inline void zfs_gid_write(struct inode *ip, gid_t gid)
  * 4.9 API change
  */
 #if !(defined(HAVE_SETATTR_PREPARE_NO_USERNS) || \
-    defined(HAVE_SETATTR_PREPARE_USERNS))
+    defined(HAVE_SETATTR_PREPARE_USERNS) || \
+    defined(HAVE_SETATTR_PREPARE_IDMAP))
 static inline int
 setattr_prepare(struct dentry *dentry, struct iattr *ia)
 {
@@ -399,6 +400,15 @@ func(struct user_namespace *user_ns, const struct path *path,	\
 	return (func##_impl(user_ns, path, stat, request_mask, \
 	    query_flags));	\
 }
+#elif defined(HAVE_IDMAP_IOPS_GETATTR)
+#define	ZPL_GETATTR_WRAPPER(func)					\
+static int								\
+func(struct mnt_idmap *user_ns, const struct path *path,	\
+    struct kstat *stat, u32 request_mask, unsigned int query_flags)	\
+{									\
+	return (func##_impl(user_ns, path, stat, request_mask,	\
+	    query_flags));	\
+}
 #else
 #error
 #endif
@@ -450,8 +460,15 @@ zpl_is_32bit_api(void)
  * 5.12 API change
  * To support id-mapped mounts, generic_fillattr() was modified to
  * accept a new struct user_namespace* as its first arg.
+ *
+ * 6.3 API change
+ * generic_fillattr() first arg is changed to struct mnt_idmap *
+ *
  */
-#ifdef HAVE_GENERIC_FILLATTR_USERNS
+#ifdef HAVE_GENERIC_FILLATTR_IDMAP
+#define	zpl_generic_fillattr(idmap, ip, sp)	\
+    generic_fillattr(idmap, ip, sp)
+#elif defined(HAVE_GENERIC_FILLATTR_USERNS)
 #define	zpl_generic_fillattr(user_ns, ip, sp)	\
     generic_fillattr(user_ns, ip, sp)
 #else
diff --git a/include/os/linux/kernel/linux/xattr_compat.h b/include/os/linux/kernel/linux/xattr_compat.h
index 30403fe873..3ffd001691 100644
--- a/include/os/linux/kernel/linux/xattr_compat.h
+++ b/include/os/linux/kernel/linux/xattr_compat.h
@@ -133,20 +133,35 @@ fn(const struct xattr_handler *handler, struct dentry *dentry,		\
 #error "Unsupported kernel"
 #endif
 
+/*
+ * 6.3 API change,
+ * The xattr_handler->set() callback was changed to take the
+ * struct mnt_idmap* as the first arg, to support idmapped
+ * mounts.
+ */
+#if defined(HAVE_XATTR_SET_IDMAP)
+#define	ZPL_XATTR_SET_WRAPPER(fn)					\
+static int								\
+fn(const struct xattr_handler *handler, struct mnt_idmap *user_ns,	\
+    struct dentry *dentry, struct inode *inode, const char *name,	\
+    const void *buffer, size_t size, int flags)	\
+{									\
+	return (__ ## fn(user_ns, inode, name, buffer, size, flags));	\
+}
 /*
  * 5.12 API change,
  * The xattr_handler->set() callback was changed to take the
  * struct user_namespace* as the first arg, to support idmapped
  * mounts.
  */
-#if defined(HAVE_XATTR_SET_USERNS)
+#elif defined(HAVE_XATTR_SET_USERNS)
 #define	ZPL_XATTR_SET_WRAPPER(fn)					\
 static int								\
 fn(const struct xattr_handler *handler, struct user_namespace *user_ns, \
     struct dentry *dentry, struct inode *inode, const char *name,	\
     const void *buffer, size_t size, int flags)	\
 {									\
-	return (__ ## fn(inode, name, buffer, size, flags));		\
+	return (__ ## fn(user_ns, inode, name, buffer, size, flags));	\
 }
 /*
  * 4.7 API change,
@@ -160,7 +175,7 @@ fn(const struct xattr_handler *handler, struct dentry *dentry,		\
     struct inode *inode, const char *name, const void *buffer,		\
     size_t size, int flags)						\
 {									\
-	return (__ ## fn(inode, name, buffer, size, flags));		\
+	return (__ ## fn(kcred->user_ns, inode, name, buffer, size, flags));\
 }
 /*
  * 4.4 API change,
@@ -174,7 +189,8 @@ 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));	\
+	return (__ ## fn(kcred->user_ns, dentry->d_inode, name,		\
+	    buffer, size, flags));					\
 }
 /*
  * 2.6.33 API change,
@@ -187,7 +203,8 @@ static int								\
 fn(struct dentry *dentry, const char *name, const void *buffer,		\
     size_t size, int flags, int unused_handler_flags)			\
 {									\
-	return (__ ## fn(dentry->d_inode, name, buffer, size, flags));	\
+	return (__ ## fn(kcred->user_ns, dentry->d_inode, name, buffer, \
+	    size, flags));						\
 }
 #else
 #error "Unsupported kernel"
diff --git a/include/os/linux/spl/sys/cred.h b/include/os/linux/spl/sys/cred.h
index b7d3f38d70..501bd4566c 100644
--- a/include/os/linux/spl/sys/cred.h
+++ b/include/os/linux/spl/sys/cred.h
@@ -45,6 +45,8 @@ typedef struct cred cred_t;
 #define	SGID_TO_KGID(x)		(KGIDT_INIT(x))
 #define	KGIDP_TO_SGIDP(x)	(&(x)->val)
 
+extern zidmap_t *zfs_get_init_idmap(void);
+
 extern void crhold(cred_t *cr);
 extern void crfree(cred_t *cr);
 extern uid_t crgetuid(const cred_t *cr);
diff --git a/include/os/linux/spl/sys/types.h b/include/os/linux/spl/sys/types.h
index b44c945187..4d638efbbc 100644
--- a/include/os/linux/spl/sys/types.h
+++ b/include/os/linux/spl/sys/types.h
@@ -54,4 +54,18 @@ typedef ulong_t			pgcnt_t;
 typedef int			major_t;
 typedef int			minor_t;
 
+struct user_namespace;
+#ifdef HAVE_IOPS_CREATE_IDMAP
+#include <linux/refcount.h>
+struct mnt_idmap {
+	struct user_namespace *owner;
+	refcount_t count;
+};
+typedef struct mnt_idmap	zidmap_t;
+#else
+typedef struct user_namespace	zidmap_t;
+#endif
+
+extern zidmap_t *zfs_init_idmap;
+
 #endif	/* _SPL_TYPES_H */
diff --git a/include/os/linux/zfs/sys/zfs_vnops_os.h b/include/os/linux/zfs/sys/zfs_vnops_os.h
index f4b78bee60..331f2e2bcc 100644
--- a/include/os/linux/zfs/sys/zfs_vnops_os.h
+++ b/include/os/linux/zfs/sys/zfs_vnops_os.h
@@ -54,8 +54,7 @@ extern int zfs_mkdir(znode_t *dzp, char *dirname, vattr_t *vap,
 extern int zfs_rmdir(znode_t *dzp, char *name, znode_t *cwd,
     cred_t *cr, int flags);
 extern int zfs_readdir(struct inode *ip, zpl_dir_context_t *ctx, cred_t *cr);
-extern int zfs_getattr_fast(struct user_namespace *, struct inode *ip,
-	struct kstat *sp);
+extern int zfs_getattr_fast(zidmap_t *, struct inode *ip, struct kstat *sp);
 extern int zfs_setattr(znode_t *zp, vattr_t *vap, int flag, cred_t *cr);
 extern int zfs_rename(znode_t *sdzp, char *snm, znode_t *tdzp,
     char *tnm, cred_t *cr, int flags);
diff --git a/include/os/linux/zfs/sys/zpl.h b/include/os/linux/zfs/sys/zpl.h
index ac9815d4ee..4e08470e79 100644
--- a/include/os/linux/zfs/sys/zpl.h
+++ b/include/os/linux/zfs/sys/zpl.h
@@ -64,7 +64,10 @@ extern int zpl_xattr_security_init(struct inode *ip, struct inode *dip,
     const struct qstr *qstr);
 #if defined(CONFIG_FS_POSIX_ACL)
 #if defined(HAVE_SET_ACL)
-#if defined(HAVE_SET_ACL_USERNS)
+#if defined(HAVE_SET_ACL_IDMAP_DENTRY)
+extern int zpl_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
+    struct posix_acl *acl, int type);
+#elif defined(HAVE_SET_ACL_USERNS)
 extern int zpl_set_acl(struct user_namespace *userns, struct inode *ip,
     struct posix_acl *acl, int type);
 #elif defined(HAVE_SET_ACL_USERNS_DENTRY_ARG2)
@@ -186,13 +189,15 @@ zpl_dir_emit_dots(struct file *file, zpl_dir_context_t *ctx)
 
 #if defined(HAVE_INODE_OWNER_OR_CAPABLE)
 #define	zpl_inode_owner_or_capable(ns, ip)	inode_owner_or_capable(ip)
-#elif defined(HAVE_INODE_OWNER_OR_CAPABLE_IDMAPPED)
+#elif defined(HAVE_INODE_OWNER_OR_CAPABLE_USERNS)
 #define	zpl_inode_owner_or_capable(ns, ip)	inode_owner_or_capable(ns, ip)
+#elif defined(HAVE_INODE_OWNER_OR_CAPABLE_IDMAP)
+#define	zpl_inode_owner_or_capable(idmap, ip) inode_owner_or_capable(idmap, ip)
 #else
 #error "Unsupported kernel"
 #endif
 
-#ifdef HAVE_SETATTR_PREPARE_USERNS
+#if defined(HAVE_SETATTR_PREPARE_USERNS) || defined(HAVE_SETATTR_PREPARE_IDMAP)
 #define	zpl_setattr_prepare(ns, dentry, ia)	setattr_prepare(ns, dentry, ia)
 #else
 /*
diff --git a/module/os/linux/spl/spl-cred.c b/module/os/linux/spl/spl-cred.c
index f81b9540a6..d407fc66b2 100644
--- a/module/os/linux/spl/spl-cred.c
+++ b/module/os/linux/spl/spl-cred.c
@@ -145,6 +145,18 @@ crgetgid(const cred_t *cr)
 	return (KGID_TO_SGID(cr->fsgid));
 }
 
+/* Return the initial user ns or nop_mnt_idmap */
+zidmap_t *
+zfs_get_init_idmap(void)
+{
+#ifdef HAVE_IOPS_CREATE_IDMAP
+	return ((zidmap_t *)&nop_mnt_idmap);
+#else
+	return ((zidmap_t *)&init_user_ns);
+#endif
+}
+
+EXPORT_SYMBOL(zfs_get_init_idmap);
 EXPORT_SYMBOL(crhold);
 EXPORT_SYMBOL(crfree);
 EXPORT_SYMBOL(crgetuid);
diff --git a/module/os/linux/zfs/policy.c b/module/os/linux/zfs/policy.c
index 5a52092bb9..8d508bcb49 100644
--- a/module/os/linux/zfs/policy.c
+++ b/module/os/linux/zfs/policy.c
@@ -124,7 +124,7 @@ secpolicy_vnode_any_access(const cred_t *cr, struct inode *ip, uid_t owner)
 	if (crgetuid(cr) == owner)
 		return (0);
 
-	if (zpl_inode_owner_or_capable(kcred->user_ns, ip))
+	if (zpl_inode_owner_or_capable(zfs_init_idmap, ip))
 		return (0);
 
 #if defined(CONFIG_USER_NS)
diff --git a/module/os/linux/zfs/zfs_ioctl_os.c b/module/os/linux/zfs/zfs_ioctl_os.c
index 79b9d777dc..767d3a377d 100644
--- a/module/os/linux/zfs/zfs_ioctl_os.c
+++ b/module/os/linux/zfs/zfs_ioctl_os.c
@@ -288,6 +288,8 @@ zfsdev_detach(void)
 #define	ZFS_DEBUG_STR	""
 #endif
 
+zidmap_t *zfs_init_idmap;
+
 static int __init
 openzfs_init(void)
 {
@@ -311,6 +313,8 @@ openzfs_init(void)
 	printk(KERN_NOTICE "ZFS: Posix ACLs disabled by kernel\n");
 #endif /* CONFIG_FS_POSIX_ACL */
 
+	zfs_init_idmap = (zidmap_t *)zfs_get_init_idmap();
+
 	return (0);
 }
 
diff --git a/module/os/linux/zfs/zfs_vnops_os.c b/module/os/linux/zfs/zfs_vnops_os.c
index 8319011291..af0d553d51 100644
--- a/module/os/linux/zfs/zfs_vnops_os.c
+++ b/module/os/linux/zfs/zfs_vnops_os.c
@@ -1675,8 +1675,7 @@ out:
  */
 /* ARGSUSED */
 int
-zfs_getattr_fast(struct user_namespace *user_ns, struct inode *ip,
-    struct kstat *sp)
+zfs_getattr_fast(zidmap_t *user_ns, struct inode *ip, struct kstat *sp)
 {
 	znode_t *zp = ITOZ(ip);
 	zfsvfs_t *zfsvfs = ITOZSB(ip);
diff --git a/module/os/linux/zfs/zpl_ctldir.c b/module/os/linux/zfs/zpl_ctldir.c
index 9b526afd00..cf4da470f2 100644
--- a/module/os/linux/zfs/zpl_ctldir.c
+++ b/module/os/linux/zfs/zpl_ctldir.c
@@ -101,7 +101,11 @@ zpl_root_readdir(struct file *filp, void *dirent, filldir_t filldir)
  */
 /* ARGSUSED */
 static int
-#ifdef HAVE_USERNS_IOPS_GETATTR
+#ifdef HAVE_IDMAP_IOPS_GETATTR
+zpl_root_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
+#elif defined(HAVE_USERNS_IOPS_GETATTR)
 zpl_root_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
@@ -112,8 +116,14 @@ zpl_root_getattr_impl(const struct path *path, struct kstat *stat,
 {
 	struct inode *ip = path->dentry->d_inode;
 
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
+#ifdef HAVE_GENERIC_FILLATTR_USERNS
 	generic_fillattr(user_ns, ip, stat);
+#elif defined(HAVE_GENERIC_FILLATTR_IDMAP)
+	generic_fillattr(user_ns, ip, stat);
+#else
+	(void) user_ns;
+#endif
 #else
 	generic_fillattr(ip, stat);
 #endif
@@ -304,6 +314,10 @@ static int
 zpl_snapdir_rename2(struct user_namespace *user_ns, struct inode *sdip,
     struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
     unsigned int flags)
+#elif defined(HAVE_IOPS_RENAME_IDMAP)
+zpl_snapdir_rename2(struct mnt_idmap *user_ns, struct inode *sdip,
+    struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
+    unsigned int flags)
 #else
 zpl_snapdir_rename2(struct inode *sdip, struct dentry *sdentry,
     struct inode *tdip, struct dentry *tdentry, unsigned int flags)
@@ -325,7 +339,9 @@ zpl_snapdir_rename2(struct inode *sdip, struct dentry *sdentry,
 	return (error);
 }
 
-#if !defined(HAVE_RENAME_WANTS_FLAGS) && !defined(HAVE_IOPS_RENAME_USERNS)
+#if (!defined(HAVE_RENAME_WANTS_FLAGS) && \
+	!defined(HAVE_IOPS_RENAME_USERNS) && \
+	!defined(HAVE_IOPS_RENAME_IDMAP))
 static int
 zpl_snapdir_rename(struct inode *sdip, struct dentry *sdentry,
     struct inode *tdip, struct dentry *tdentry)
@@ -352,6 +368,9 @@ static int
 #ifdef HAVE_IOPS_MKDIR_USERNS
 zpl_snapdir_mkdir(struct user_namespace *user_ns, struct inode *dip,
     struct dentry *dentry, umode_t mode)
+#elif defined(HAVE_IOPS_MKDIR_IDMAP)
+zpl_snapdir_mkdir(struct mnt_idmap *user_ns, struct inode *dip,
+    struct dentry *dentry, umode_t mode)
 #else
 zpl_snapdir_mkdir(struct inode *dip, struct dentry *dentry, umode_t mode)
 #endif
@@ -384,7 +403,11 @@ zpl_snapdir_mkdir(struct inode *dip, struct dentry *dentry, umode_t mode)
  */
 /* ARGSUSED */
 static int
-#ifdef HAVE_USERNS_IOPS_GETATTR
+#ifdef HAVE_IDMAP_IOPS_GETATTR
+zpl_snapdir_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
+#elif defined(HAVE_USERNS_IOPS_GETATTR)
 zpl_snapdir_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
@@ -397,8 +420,14 @@ zpl_snapdir_getattr_impl(const struct path *path, struct kstat *stat,
 	zfsvfs_t *zfsvfs = ITOZSB(ip);
 
 	ZPL_ENTER(zfsvfs);
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
+#ifdef HAVE_GENERIC_FILLATTR_USERNS
 	generic_fillattr(user_ns, ip, stat);
+#elif defined(HAVE_GENERIC_FILLATTR_IDMAP)
+	generic_fillattr(user_ns, ip, stat);
+#else
+	(void) user_ns;
+#endif
 #else
 	generic_fillattr(ip, stat);
 #endif
@@ -439,7 +468,9 @@ const struct file_operations zpl_fops_snapdir = {
 const struct inode_operations zpl_ops_snapdir = {
 	.lookup		= zpl_snapdir_lookup,
 	.getattr	= zpl_snapdir_getattr,
-#if defined(HAVE_RENAME_WANTS_FLAGS) || defined(HAVE_IOPS_RENAME_USERNS)
+#if (defined(HAVE_RENAME_WANTS_FLAGS) || \
+	defined(HAVE_IOPS_RENAME_USERNS) || \
+	defined(HAVE_IOPS_RENAME_IDMAP))
 	.rename		= zpl_snapdir_rename2,
 #else
 	.rename		= zpl_snapdir_rename,
@@ -530,6 +561,10 @@ static int
 zpl_shares_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
+#elif defined(HAVE_IDMAP_IOPS_GETATTR)
+zpl_shares_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
 #else
 zpl_shares_getattr_impl(const struct path *path, struct kstat *stat,
     u32 request_mask, unsigned int query_flags)
@@ -543,8 +578,14 @@ zpl_shares_getattr_impl(const struct path *path, struct kstat *stat,
 	ZPL_ENTER(zfsvfs);
 
 	if (zfsvfs->z_shares_dir == 0) {
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
+#ifdef HAVE_GENERIC_FILLATTR_USERNS
 		generic_fillattr(user_ns, path->dentry->d_inode, stat);
+#elif defined(HAVE_GENERIC_FILLATTR_IDMAP)
+		generic_fillattr(user_ns, path->dentry->d_inode, stat);
+#else
+		(void) user_ns;
+#endif
 #else
 		generic_fillattr(path->dentry->d_inode, stat);
 #endif
@@ -556,7 +597,7 @@ zpl_shares_getattr_impl(const struct path *path, struct kstat *stat,
 
 	error = -zfs_zget(zfsvfs, zfsvfs->z_shares_dir, &dzp);
 	if (error == 0) {
-#if defined(HAVE_GENERIC_FILLATTR_USERNS) && defined(HAVE_USERNS_IOPS_GETATTR)
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
 		error = -zfs_getattr_fast(user_ns, ZTOI(dzp), stat);
 #else
 		error = -zfs_getattr_fast(kcred->user_ns, ZTOI(dzp), stat);
diff --git a/module/os/linux/zfs/zpl_file.c b/module/os/linux/zfs/zpl_file.c
index f7c254c167..d5d354db16 100644
--- a/module/os/linux/zfs/zpl_file.c
+++ b/module/os/linux/zfs/zpl_file.c
@@ -978,7 +978,7 @@ __zpl_ioctl_setflags(struct inode *ip, uint32_t ioctl_flags, xvattr_t *xva)
 	    !capable(CAP_LINUX_IMMUTABLE))
 		return (-EPERM);
 
-	if (!zpl_inode_owner_or_capable(kcred->user_ns, ip))
+	if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
 		return (-EACCES);
 
 	xva_init(xva);
diff --git a/module/os/linux/zfs/zpl_inode.c b/module/os/linux/zfs/zpl_inode.c
index dd634f70eb..6efaaf4388 100644
--- a/module/os/linux/zfs/zpl_inode.c
+++ b/module/os/linux/zfs/zpl_inode.c
@@ -131,6 +131,9 @@ static int
 #ifdef HAVE_IOPS_CREATE_USERNS
 zpl_create(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, umode_t mode, bool flag)
+#elif defined(HAVE_IOPS_CREATE_IDMAP)
+zpl_create(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, umode_t mode, bool flag)
 #else
 zpl_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool flag)
 #endif
@@ -174,6 +177,9 @@ static int
 #ifdef HAVE_IOPS_MKNOD_USERNS
 zpl_mknod(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, umode_t mode,
+#elif defined(HAVE_IOPS_MKNOD_IDMAP)
+zpl_mknod(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, umode_t mode,
 #else
 zpl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 #endif
@@ -224,7 +230,10 @@ zpl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
 
 #ifdef HAVE_TMPFILE
 static int
-#ifndef HAVE_TMPFILE_DENTRY
+#ifdef HAVE_TMPFILE_IDMAP
+zpl_tmpfile(struct mnt_idmap *userns, struct inode *dir,
+    struct file *file, umode_t mode)
+#elif !defined(HAVE_TMPFILE_DENTRY)
 zpl_tmpfile(struct user_namespace *userns, struct inode *dir,
     struct file *file, umode_t mode)
 #else
@@ -317,6 +326,9 @@ static int
 #ifdef HAVE_IOPS_MKDIR_USERNS
 zpl_mkdir(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, umode_t mode)
+#elif defined(HAVE_IOPS_MKDIR_IDMAP)
+zpl_mkdir(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, umode_t mode)
 #else
 zpl_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 #endif
@@ -386,6 +398,10 @@ static int
 zpl_getattr_impl(struct user_namespace *user_ns,
     const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
+#elif defined(HAVE_IDMAP_IOPS_GETATTR)
+zpl_getattr_impl(struct mnt_idmap *user_ns,
+    const struct path *path, struct kstat *stat, u32 request_mask,
+    unsigned int query_flags)
 #else
 zpl_getattr_impl(const struct path *path, struct kstat *stat, u32 request_mask,
     unsigned int query_flags)
@@ -402,7 +418,7 @@ zpl_getattr_impl(const struct path *path, struct kstat *stat, u32 request_mask,
 	 * XXX query_flags currently ignored.
 	 */
 
-#ifdef HAVE_USERNS_IOPS_GETATTR
+#if (defined(HAVE_USERNS_IOPS_GETATTR) || defined(HAVE_IDMAP_IOPS_GETATTR))
 	error = -zfs_getattr_fast(user_ns, ip, stat);
 #else
 	error = -zfs_getattr_fast(kcred->user_ns, ip, stat);
@@ -441,9 +457,12 @@ zpl_getattr_impl(const struct path *path, struct kstat *stat, u32 request_mask,
 ZPL_GETATTR_WRAPPER(zpl_getattr);
 
 static int
-#ifdef HAVE_SETATTR_PREPARE_USERNS
+#ifdef HAVE_USERNS_IOPS_SETATTR
 zpl_setattr(struct user_namespace *user_ns, struct dentry *dentry,
     struct iattr *ia)
+#elif defined(HAVE_IDMAP_IOPS_SETATTR)
+zpl_setattr(struct mnt_idmap *user_ns, struct dentry *dentry,
+    struct iattr *ia)
 #else
 zpl_setattr(struct dentry *dentry, struct iattr *ia)
 #endif
@@ -454,7 +473,13 @@ zpl_setattr(struct dentry *dentry, struct iattr *ia)
 	int error;
 	fstrans_cookie_t cookie;
 
-	error = zpl_setattr_prepare(kcred->user_ns, dentry, ia);
+#ifdef HAVE_SETATTR_PREPARE_USERNS
+	error = zpl_setattr_prepare(user_ns, dentry, ia);
+#elif defined(HAVE_SETATTR_PREPARE_IDMAP)
+	error = zpl_setattr_prepare(user_ns, dentry, ia);
+#else
+	error = zpl_setattr_prepare(zfs_init_idmap, dentry, ia);
+#endif
 	if (error)
 		return (error);
 
@@ -489,10 +514,14 @@ static int
 #ifdef HAVE_IOPS_RENAME_USERNS
 zpl_rename2(struct user_namespace *user_ns, struct inode *sdip,
     struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
-    unsigned int flags)
+    unsigned int rflags)
+#elif defined(HAVE_IOPS_RENAME_IDMAP)
+zpl_rename2(struct mnt_idmap *user_ns, struct inode *sdip,
+    struct dentry *sdentry, struct inode *tdip, struct dentry *tdentry,
+    unsigned int rflags)
 #else
 zpl_rename2(struct inode *sdip, struct dentry *sdentry,
-    struct inode *tdip, struct dentry *tdentry, unsigned int flags)
+    struct inode *tdip, struct dentry *tdentry, unsigned int rflags)
 #endif
 {
 	cred_t *cr = CRED();
@@ -500,7 +529,7 @@ zpl_rename2(struct inode *sdip, struct dentry *sdentry,
 	fstrans_cookie_t cookie;
 
 	/* We don't have renameat2(2) support */
-	if (flags)
+	if (rflags)
 		return (-EINVAL);
 
 	crhold(cr);
@@ -514,7 +543,9 @@ zpl_rename2(struct inode *sdip, struct dentry *sdentry,
 	return (error);
 }
 
-#if !defined(HAVE_RENAME_WANTS_FLAGS) && !defined(HAVE_IOPS_RENAME_USERNS)
+#if !defined(HAVE_IOPS_RENAME_USERNS) && \
+	!defined(HAVE_RENAME_WANTS_FLAGS) && \
+	!defined(HAVE_IOPS_RENAME_IDMAP)
 static int
 zpl_rename(struct inode *sdip, struct dentry *sdentry,
     struct inode *tdip, struct dentry *tdentry)
@@ -527,6 +558,9 @@ static int
 #ifdef HAVE_IOPS_SYMLINK_USERNS
 zpl_symlink(struct user_namespace *user_ns, struct inode *dir,
     struct dentry *dentry, const char *name)
+#elif defined(HAVE_IOPS_SYMLINK_IDMAP)
+zpl_symlink(struct mnt_idmap *user_ns, struct inode *dir,
+    struct dentry *dentry, const char *name)
 #else
 zpl_symlink(struct inode *dir, struct dentry *dentry, const char *name)
 #endif
@@ -745,6 +779,8 @@ const struct inode_operations zpl_dir_inode_operations = {
 	.mknod		= zpl_mknod,
 #if defined(HAVE_RENAME_WANTS_FLAGS) || defined(HAVE_IOPS_RENAME_USERNS)
 	.rename		= zpl_rename2,
+#elif defined(HAVE_IOPS_RENAME_IDMAP)
+	.rename		= zpl_rename2,
 #else
 	.rename		= zpl_rename,
 #endif
diff --git a/module/os/linux/zfs/zpl_xattr.c b/module/os/linux/zfs/zpl_xattr.c
index 364cd34c16..0848176098 100644
--- a/module/os/linux/zfs/zpl_xattr.c
+++ b/module/os/linux/zfs/zpl_xattr.c
@@ -725,9 +725,11 @@ __zpl_xattr_user_get(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_user_get);
 
 static int
-__zpl_xattr_user_set(struct inode *ip, const char *name,
+__zpl_xattr_user_set(zidmap_t *user_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
+	(void) user_ns;
 	char *xattr_name;
 	int error;
 	/* xattr_resolve_name will do this for us if this is defined */
@@ -794,9 +796,11 @@ __zpl_xattr_trusted_get(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_trusted_get);
 
 static int
-__zpl_xattr_trusted_set(struct inode *ip, const char *name,
+__zpl_xattr_trusted_set(zidmap_t *user_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
+	(void) user_ns;
 	char *xattr_name;
 	int error;
 
@@ -863,9 +867,11 @@ __zpl_xattr_security_get(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_security_get);
 
 static int
-__zpl_xattr_security_set(struct inode *ip, const char *name,
+__zpl_xattr_security_set(zidmap_t *user_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
+	(void) user_ns;
 	char *xattr_name;
 	int error;
 	/* xattr_resolve_name will do this for us if this is defined */
@@ -889,7 +895,7 @@ zpl_xattr_security_init_impl(struct inode *ip, const struct xattr *xattrs,
 	int error = 0;
 
 	for (xattr = xattrs; xattr->name != NULL; xattr++) {
-		error = __zpl_xattr_security_set(ip,
+		error = __zpl_xattr_security_set(NULL, ip,
 		    xattr->name, xattr->value, xattr->value_len, 0);
 
 		if (error < 0)
@@ -1004,6 +1010,9 @@ int
 #ifdef HAVE_SET_ACL_USERNS
 zpl_set_acl(struct user_namespace *userns, struct inode *ip,
     struct posix_acl *acl, int type)
+#elif defined(HAVE_SET_ACL_IDMAP_DENTRY)
+zpl_set_acl(struct mnt_idmap *userns, struct dentry *dentry,
+    struct posix_acl *acl, int type)
 #elif defined(HAVE_SET_ACL_USERNS_DENTRY_ARG2)
 zpl_set_acl(struct user_namespace *userns, struct dentry *dentry,
     struct posix_acl *acl, int type)
@@ -1013,6 +1022,8 @@ zpl_set_acl(struct inode *ip, struct posix_acl *acl, int type)
 {
 #ifdef HAVE_SET_ACL_USERNS_DENTRY_ARG2
 	return (zpl_set_acl_impl(d_inode(dentry), acl, type));
+#elif defined(HAVE_SET_ACL_IDMAP_DENTRY)
+	return (zpl_set_acl_impl(d_inode(dentry), acl, type));
 #else
 	return (zpl_set_acl_impl(ip, acl, type));
 #endif /* HAVE_SET_ACL_USERNS_DENTRY_ARG2 */
@@ -1256,7 +1267,8 @@ __zpl_xattr_acl_get_default(struct inode *ip, const char *name,
 ZPL_XATTR_GET_WRAPPER(zpl_xattr_acl_get_default);
 
 static int
-__zpl_xattr_acl_set_access(struct inode *ip, const char *name,
+__zpl_xattr_acl_set_access(zidmap_t *mnt_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
 	struct posix_acl *acl;
@@ -1270,8 +1282,14 @@ __zpl_xattr_acl_set_access(struct inode *ip, const char *name,
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIX)
 		return (-EOPNOTSUPP);
 
-	if (!zpl_inode_owner_or_capable(kcred->user_ns, ip))
+#if defined(HAVE_XATTR_SET_USERNS) || defined(HAVE_XATTR_SET_IDMAP)
+	if (!zpl_inode_owner_or_capable(mnt_ns, ip))
 		return (-EPERM);
+#else
+	(void) mnt_ns;
+	if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
+		return (-EPERM);
+#endif
 
 	if (value) {
 		acl = zpl_acl_from_xattr(value, size);
@@ -1295,7 +1313,8 @@ __zpl_xattr_acl_set_access(struct inode *ip, const char *name,
 ZPL_XATTR_SET_WRAPPER(zpl_xattr_acl_set_access);
 
 static int
-__zpl_xattr_acl_set_default(struct inode *ip, const char *name,
+__zpl_xattr_acl_set_default(zidmap_t *mnt_ns,
+    struct inode *ip, const char *name,
     const void *value, size_t size, int flags)
 {
 	struct posix_acl *acl;
@@ -1309,8 +1328,14 @@ __zpl_xattr_acl_set_default(struct inode *ip, const char *name,
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIX)
 		return (-EOPNOTSUPP);
 
-	if (!zpl_inode_owner_or_capable(kcred->user_ns, ip))
+#if defined(HAVE_XATTR_SET_USERNS) || defined(HAVE_XATTR_SET_IDMAP)
+	if (!zpl_inode_owner_or_capable(mnt_ns, ip))
 		return (-EPERM);
+#else
+	(void) mnt_ns;
+	if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
+		return (-EPERM);
+#endif
 
 	if (value) {
 		acl = zpl_acl_from_xattr(value, size);