Add zstd support to the boot loader.

Add support to the _STANDALONE environment enough bits of the kernel
that we can compile it. We still have a small zstd_shim.c since there
were 3 items that were a bit hard to nail down and may be cleaned up
in the future. These go hand in hand with a number of commits to
sys/sys in the past weeks, should this need be MFCd.

Discussed with: mmacy (in review and on IRC/Slack)
Reviewed by: freqlabs (on openzfs repo)
Differential Revision: https://reviews.freebsd.org/D26218

stand/efi/boot1/Makefile

@@ -40,6 +40,7 @@ CFLAGS.zfs_module.c+=	-I${SYSDIR}/contrib/openzfs/include
 CFLAGS.zfs_module.c+=	-I${SYSDIR}/contrib/openzfs/include/os/freebsd/spl
 CFLAGS.zfs_module.c+=	-I${SYSDIR}/contrib/openzfs/include/os/freebsd/zfs
 CFLAGS.zfs_module.c+=	-I${SYSDIR}/cddl/contrib/opensolaris/common/lz4
+CFLAGS.zfs_module.c+=	-include ${ZFSOSINC}/spl/sys/ccompile.h
 
 CFLAGS+=	-DEFI_ZFS_BOOT
 .endif

stand/libsa/zfs/Makefile.inc

@@ -1,17 +1,37 @@
 # $FreeBSD$
 
 .PATH:		${ZFSSRC}
-SRCS+=		zfs.c nvlist.c skein.c skein_block.c list.c
 .PATH:		${SYSDIR}/crypto/skein
-.PATH:		${SYSDIR}/cddl/contrib/opensolaris/uts/common/os
+.PATH:		${ZFSOSSRC}/spl
+.PATH:		${OZFS}/module/zstd/lib
+ZFSSRC=		zfs.c nvlist.c skein.c skein_block.c list.c zstd_shim.c zstd.c
+SRCS+=		${ZFSSRC}
 
 CFLAGS+=	-I${LDRSRC}
 CFLAGS+=	-I${SYSDIR}/cddl/boot/zfs
-CFLAGS+=	-I${SYSDIR}/cddl/contrib/opensolaris/uts/common
 CFLAGS+=	-I${SYSDIR}/crypto/skein
 
+ZFS_EARLY=	-I${ZFSOSINC}					\
+		-I${ZFSOSINC}/spl				\
+		-I${ZFSOSINC}/zfs
+
+.for i in ${ZFSSRC}
+CFLAGS.$i+=	-include ${ZFSOSINC}/spl/sys/ccompile.h
+.endfor
+
+CFLAGS_EARLY.list.c+= ${ZFS_EARLY}
+CFLAGS_EARLY.zstd_shim.c+= ${ZFS_EARLY}
+
+# Can't use the early flags because there's two conflicting definitions of boolean_t in
+# the zfs code that need to be unified.
+CFLAGS.nvlist.c+= -I${ZFSOSINC}/spl
+CFLAGS.zfs.c+=	-I${ZFSOSINC}/spl 				\
+		-I${SRCTOP}/sys/cddl/contrib/opensolaris/common/lz4
+CFLAGS.zstd_shim.c+= -DIN_BASE -I${OZFS}/include
+
 # Do not unroll skein loops, reduce code size
 CFLAGS.skein_block.c+=	-DSKEIN_LOOP=111
+
 CFLAGS+=	-I${SYSDIR}/contrib/openzfs/include
 CFLAGS+=	-I${SYSDIR}/contrib/openzfs/include/os/freebsd/zfs
 CFLAGS.zfs.c+=	-I${SYSDIR}/cddl/contrib/opensolaris/common/lz4

stand/libsa/zfs/zfsimpl.c

@@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$");
 #include "zfsimpl.h"
 #include "zfssubr.c"
 
+extern int zstd_init(void);
 
 struct zfsmount {
 	const spa_t	*spa;
@@ -170,6 +171,7 @@ zfs_init(void)
 	dnode_cache_buf = malloc(SPA_MAXBLOCKSIZE);
 
 	zfs_init_crc();
+	zstd_init();
 }
 
 static int

stand/libsa/zfs/zstd_shim.c

@@ -0,0 +1,40 @@
+/*-
+ * Copyright (c) 2020 M. Warner Losh <imp@FreeBSD.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * Small amount of shim code needed to get zfs_zstd.c to compile. These items
+ * here should all be defined in the SPL or as part of libstand somewhere, but
+ * aren't for reasons that haven't been tracked down yet. Ideally, they would
+ * all go away and we'd compile zfs_zstd.c directly. Based on an original by
+ * Matt Macey, but only the #include remains untouched from that.
+ */
+
+#define ZFS_MODULE_PARAM_ARGS void
+typedef int boolean_t;	/* This one may be tough to get rid of */
+
+#include <contrib/openzfs/module/zstd/zfs_zstd.c>

sys/cddl/boot/zfs/zfsimpl.h

@@ -611,9 +611,63 @@ enum zio_compress {
 	ZIO_COMPRESS_GZIP_9,
 	ZIO_COMPRESS_ZLE,
 	ZIO_COMPRESS_LZ4,
+	ZIO_COMPRESS_ZSTD,
 	ZIO_COMPRESS_FUNCTIONS
 };
 
+enum zio_zstd_levels {
+	ZIO_ZSTD_LEVEL_INHERIT = 0,
+	ZIO_ZSTD_LEVEL_1,
+#define	ZIO_ZSTD_LEVEL_MIN	ZIO_ZSTD_LEVEL_1
+	ZIO_ZSTD_LEVEL_2,
+	ZIO_ZSTD_LEVEL_3,
+#define	ZIO_ZSTD_LEVEL_DEFAULT	ZIO_ZSTD_LEVEL_3
+	ZIO_ZSTD_LEVEL_4,
+	ZIO_ZSTD_LEVEL_5,
+	ZIO_ZSTD_LEVEL_6,
+	ZIO_ZSTD_LEVEL_7,
+	ZIO_ZSTD_LEVEL_8,
+	ZIO_ZSTD_LEVEL_9,
+	ZIO_ZSTD_LEVEL_10,
+	ZIO_ZSTD_LEVEL_11,
+	ZIO_ZSTD_LEVEL_12,
+	ZIO_ZSTD_LEVEL_13,
+	ZIO_ZSTD_LEVEL_14,
+	ZIO_ZSTD_LEVEL_15,
+	ZIO_ZSTD_LEVEL_16,
+	ZIO_ZSTD_LEVEL_17,
+	ZIO_ZSTD_LEVEL_18,
+	ZIO_ZSTD_LEVEL_19,
+#define	ZIO_ZSTD_LEVEL_MAX	ZIO_ZSTD_LEVEL_19
+	ZIO_ZSTD_LEVEL_RESERVE = 101, /* Leave room for new positive levels */
+	ZIO_ZSTD_LEVEL_FAST, /* Fast levels are negative */
+	ZIO_ZSTD_LEVEL_FAST_1,
+#define	ZIO_ZSTD_LEVEL_FAST_DEFAULT	ZIO_ZSTD_LEVEL_FAST_1
+	ZIO_ZSTD_LEVEL_FAST_2,
+	ZIO_ZSTD_LEVEL_FAST_3,
+	ZIO_ZSTD_LEVEL_FAST_4,
+	ZIO_ZSTD_LEVEL_FAST_5,
+	ZIO_ZSTD_LEVEL_FAST_6,
+	ZIO_ZSTD_LEVEL_FAST_7,
+	ZIO_ZSTD_LEVEL_FAST_8,
+	ZIO_ZSTD_LEVEL_FAST_9,
+	ZIO_ZSTD_LEVEL_FAST_10,
+	ZIO_ZSTD_LEVEL_FAST_20,
+	ZIO_ZSTD_LEVEL_FAST_30,
+	ZIO_ZSTD_LEVEL_FAST_40,
+	ZIO_ZSTD_LEVEL_FAST_50,
+	ZIO_ZSTD_LEVEL_FAST_60,
+	ZIO_ZSTD_LEVEL_FAST_70,
+	ZIO_ZSTD_LEVEL_FAST_80,
+	ZIO_ZSTD_LEVEL_FAST_90,
+	ZIO_ZSTD_LEVEL_FAST_100,
+	ZIO_ZSTD_LEVEL_FAST_500,
+	ZIO_ZSTD_LEVEL_FAST_1000,
+#define	ZIO_ZSTD_LEVEL_FAST_MAX	ZIO_ZSTD_LEVEL_FAST_1000
+	ZIO_ZSTD_LEVEL_AUTO = 251, /* Reserved for future use */
+	ZIO_ZSTD_LEVEL_LEVELS
+};
+
 #define	ZIO_COMPRESS_ON_VALUE	ZIO_COMPRESS_LZJB
 #define	ZIO_COMPRESS_DEFAULT	ZIO_COMPRESS_OFF
 

sys/cddl/boot/zfs/zfssubr.c

@@ -30,8 +30,6 @@ __FBSDID("$FreeBSD$");
 
 static uint64_t zfs_crc64_table[256];
 
-#define	ECKSUM	666
-
 #define	ASSERT3S(x, y, z)	((void)0)
 #define	ASSERT3U(x, y, z)	((void)0)
 #define	ASSERT3P(x, y, z)	((void)0)
@@ -107,6 +105,10 @@ typedef struct zio_checksum_info {
 #include "sha256.c"
 #include "skein_zfs.c"
 
+extern int zfs_zstd_decompress(void *s_start, void *d_start, size_t s_len,
+    size_t d_len, int n);
+
+
 static zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = {
 	{{NULL, NULL}, NULL, NULL, 0, "inherit"},
 	{{NULL, NULL}, NULL, NULL, 0, "on"},
@@ -181,6 +183,7 @@ static zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS] = {
 	{NULL,			NULL,			9,	"gzip-9"},
 	{NULL,			zle_decompress,		64,	"zle"},
 	{NULL,			lz4_decompress,		0,	"lz4"},
+	{NULL,			zfs_zstd_decompress, ZIO_ZSTD_LEVEL_DEFAULT, "zstd"}
 };
 
 static void

sys/cddl/contrib/opensolaris/uts/common/os/list.c

@@ -1,243 +0,0 @@
-/*
- * CDDL HEADER START
- *
- * The contents of this file are subject to the terms of the
- * Common Development and Distribution License (the "License").
- * You may not use this file except in compliance with the License.
- *
- * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
- * or http://www.opensolaris.org/os/licensing.
- * See the License for the specific language governing permissions
- * and limitations under the License.
- *
- * When distributing Covered Code, include this CDDL HEADER in each
- * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
- * If applicable, add the following below this CDDL HEADER, with the
- * fields enclosed by brackets "[]" replaced with your own identifying
- * information: Portions Copyright [yyyy] [name of copyright owner]
- *
- * CDDL HEADER END
- */
-/*
- * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
- */
-
-/*
- * Generic doubly-linked list implementation
- */
-
-#include <sys/list.h>
-#include <sys/list_impl.h>
-#include <sys/types.h>
-#include <sys/sysmacros.h>
-#include <sys/debug.h>
-
-#define	list_d2l(a, obj) ((list_node_t *)(((char *)obj) + (a)->list_offset))
-#define	list_object(a, node) ((void *)(((char *)node) - (a)->list_offset))
-#define	list_empty(a) ((a)->list_head.list_next == &(a)->list_head)
-
-#define	list_insert_after_node(list, node, object) {	\
-	list_node_t *lnew = list_d2l(list, object);	\
-	lnew->list_prev = (node);			\
-	lnew->list_next = (node)->list_next;		\
-	(node)->list_next->list_prev = lnew;		\
-	(node)->list_next = lnew;			\
-}
-
-#define	list_insert_before_node(list, node, object) {	\
-	list_node_t *lnew = list_d2l(list, object);	\
-	lnew->list_next = (node);			\
-	lnew->list_prev = (node)->list_prev;		\
-	(node)->list_prev->list_next = lnew;		\
-	(node)->list_prev = lnew;			\
-}
-
-#define	list_remove_node(node)					\
-	(node)->list_prev->list_next = (node)->list_next;	\
-	(node)->list_next->list_prev = (node)->list_prev;	\
-	(node)->list_next = (node)->list_prev = NULL
-
-void
-list_create(list_t *list, size_t size, size_t offset)
-{
-	ASSERT(list);
-	ASSERT(size > 0);
-	ASSERT(size >= offset + sizeof (list_node_t));
-
-	list->list_size = size;
-	list->list_offset = offset;
-	list->list_head.list_next = list->list_head.list_prev =
-	    &list->list_head;
-}
-
-void
-list_destroy(list_t *list)
-{
-	list_node_t *node = &list->list_head;
-
-	ASSERT(list);
-	ASSERT(list->list_head.list_next == node);
-	ASSERT(list->list_head.list_prev == node);
-
-	node->list_next = node->list_prev = NULL;
-}
-
-void
-list_insert_after(list_t *list, void *object, void *nobject)
-{
-	if (object == NULL) {
-		list_insert_head(list, nobject);
-	} else {
-		list_node_t *lold = list_d2l(list, object);
-		list_insert_after_node(list, lold, nobject);
-	}
-}
-
-void
-list_insert_before(list_t *list, void *object, void *nobject)
-{
-	if (object == NULL) {
-		list_insert_tail(list, nobject);
-	} else {
-		list_node_t *lold = list_d2l(list, object);
-		list_insert_before_node(list, lold, nobject);
-	}
-}
-
-void
-list_insert_head(list_t *list, void *object)
-{
-	list_node_t *lold = &list->list_head;
-	list_insert_after_node(list, lold, object);
-}
-
-void
-list_insert_tail(list_t *list, void *object)
-{
-	list_node_t *lold = &list->list_head;
-	list_insert_before_node(list, lold, object);
-}
-
-void
-list_remove(list_t *list, void *object)
-{
-	list_node_t *lold = list_d2l(list, object);
-	ASSERT(!list_empty(list));
-	ASSERT(lold->list_next != NULL);
-	list_remove_node(lold);
-}
-
-void *
-list_remove_head(list_t *list)
-{
-	list_node_t *head = list->list_head.list_next;
-	if (head == &list->list_head)
-		return (NULL);
-	list_remove_node(head);
-	return (list_object(list, head));
-}
-
-void *
-list_remove_tail(list_t *list)
-{
-	list_node_t *tail = list->list_head.list_prev;
-	if (tail == &list->list_head)
-		return (NULL);
-	list_remove_node(tail);
-	return (list_object(list, tail));
-}
-
-void *
-list_head(list_t *list)
-{
-	if (list_empty(list))
-		return (NULL);
-	return (list_object(list, list->list_head.list_next));
-}
-
-void *
-list_tail(list_t *list)
-{
-	if (list_empty(list))
-		return (NULL);
-	return (list_object(list, list->list_head.list_prev));
-}
-
-void *
-list_next(list_t *list, void *object)
-{
-	list_node_t *node = list_d2l(list, object);
-
-	if (node->list_next != &list->list_head)
-		return (list_object(list, node->list_next));
-
-	return (NULL);
-}
-
-void *
-list_prev(list_t *list, void *object)
-{
-	list_node_t *node = list_d2l(list, object);
-
-	if (node->list_prev != &list->list_head)
-		return (list_object(list, node->list_prev));
-
-	return (NULL);
-}
-
-/*
- *  Insert src list after dst list. Empty src list thereafter.
- */
-void
-list_move_tail(list_t *dst, list_t *src)
-{
-	list_node_t *dstnode = &dst->list_head;
-	list_node_t *srcnode = &src->list_head;
-
-	ASSERT(dst->list_size == src->list_size);
-	ASSERT(dst->list_offset == src->list_offset);
-
-	if (list_empty(src))
-		return;
-
-	dstnode->list_prev->list_next = srcnode->list_next;
-	srcnode->list_next->list_prev = dstnode->list_prev;
-	dstnode->list_prev = srcnode->list_prev;
-	srcnode->list_prev->list_next = dstnode;
-
-	/* empty src list */
-	srcnode->list_next = srcnode->list_prev = srcnode;
-}
-
-void
-list_link_replace(list_node_t *lold, list_node_t *lnew)
-{
-	ASSERT(list_link_active(lold));
-	ASSERT(!list_link_active(lnew));
-
-	lnew->list_next = lold->list_next;
-	lnew->list_prev = lold->list_prev;
-	lold->list_prev->list_next = lnew;
-	lold->list_next->list_prev = lnew;
-	lold->list_next = lold->list_prev = NULL;
-}
-
-void
-list_link_init(list_node_t *link)
-{
-	link->list_next = NULL;
-	link->list_prev = NULL;
-}
-
-int
-list_link_active(list_node_t *link)
-{
-	return (link->list_next != NULL);
-}
-
-int
-list_is_empty(list_t *list)
-{
-	return (list_empty(list));
-}

sys/contrib/openzfs/include/os/freebsd/linux/compiler.h

@@ -68,7 +68,7 @@
 #define	noinline			__noinline
 #define	____cacheline_aligned		__aligned(CACHE_LINE_SIZE)
 
-#ifndef _KERNEL
+#if !defined(_KERNEL) && !defined(_STANDALONE)
 #define	likely(x)			__builtin_expect(!!(x), 1)
 #define	unlikely(x)			__builtin_expect(!!(x), 0)
 #endif

sys/contrib/openzfs/include/os/freebsd/spl/rpc/xdr.h

@@ -33,7 +33,7 @@
 #include <rpc/types.h>
 #include_next <rpc/xdr.h>
 
-#ifndef _KERNEL
+#if !defined(_KERNEL) && !defined(_STANDALONE)
 
 #include <assert.h>
 
@@ -66,6 +66,6 @@ xdrmem_control(XDR *xdrs, int request, void *info)
 	    xdrmem_control((xdrs), (req), (op)) :			\
 	    (*(xdrs)->x_ops->x_control)(xdrs, req, op))
 
-#endif	/* !_KERNEL */
+#endif	/* !_KERNEL && !_STANDALONE */
 
 #endif	/* !_OPENSOLARIS_RPC_XDR_H_ */

sys/contrib/openzfs/include/os/freebsd/spl/sys/atomic.h

@@ -29,6 +29,8 @@
 #ifndef _OPENSOLARIS_SYS_ATOMIC_H_
 #define	_OPENSOLARIS_SYS_ATOMIC_H_
 
+#ifndef _STANDALONE
+
 #include <sys/types.h>
 #include <machine/atomic.h>
 
@@ -179,4 +181,13 @@ atomic_cas_ptr(volatile void *target, void *cmp,  void *newval)
 }
 #endif	/* !defined(COMPAT_32BIT) && defined(__LP64__) */
 
+#else /* _STANDALONE */
+/*
+ * sometimes atomic_add_64 is defined, sometimes not, but the
+ * following is always right for the boot loader.
+ */
+#undef atomic_add_64
+#define	atomic_add_64(ptr, val) *(ptr) += val
+#endif /* !_STANDALONE */
+
 #endif	/* !_OPENSOLARIS_SYS_ATOMIC_H_ */

sys/contrib/openzfs/include/os/freebsd/spl/sys/byteorder.h

@@ -80,10 +80,11 @@
 #define	BE_64(x)	BSWAP_64(x)
 #endif
 
+#if !defined(_STANDALONE)
 #if BYTE_ORDER == _BIG_ENDIAN
 #define	htonll(x)	BMASK_64(x)
 #define	ntohll(x)	BMASK_64(x)
-#else
+#else /* BYTE_ORDER == _LITTLE_ENDIAN */
 #ifndef __LP64__
 static __inline__ uint64_t
 htonll(uint64_t n)
@@ -96,11 +97,12 @@ ntohll(uint64_t n)
 {
 	return ((((uint64_t)ntohl(n)) << 32) + ntohl(n >> 32));
 }
-#else
+#else	/* !__LP64__ */
 #define	htonll(x)	BSWAP_64(x)
 #define	ntohll(x)	BSWAP_64(x)
-#endif
+#endif	/* __LP64__ */
-#endif
+#endif	/* BYTE_ORDER */
+#endif	/* _STANDALONE */
 
 #define	BE_IN32(xa)	htonl(*((uint32_t *)(void *)(xa)))
 

sys/contrib/openzfs/include/os/freebsd/spl/sys/ccompile.h

@@ -113,9 +113,9 @@ extern "C" {
 #define	__VPRINTFLIKE(__n)	__sun_attr__((__VPRINTFLIKE__(__n)))
 #define	__KPRINTFLIKE(__n)	__sun_attr__((__KPRINTFLIKE__(__n)))
 #define	__KVPRINTFLIKE(__n)	__sun_attr__((__KVPRINTFLIKE__(__n)))
-#ifdef _KERNEL
+#if	defined(_KERNEL) || defined(_STANDALONE)
 #define	__NORETURN		__sun_attr__((__noreturn__))
-#endif
+#endif /* _KERNEL || _STANDALONE */
 #define	__CONST			__sun_attr__((__const__))
 #define	__PURE			__sun_attr__((__pure__))
 
@@ -174,7 +174,7 @@ typedef int enum_t;
 #define	__exit
 #endif
 
-#ifdef _KERNEL
+#if defined(_KERNEL) || defined(_STANDALONE)
 #define	param_set_charp(a, b) (0)
 #define	ATTR_UID AT_UID
 #define	ATTR_GID AT_GID
@@ -183,9 +183,15 @@ typedef int enum_t;
 #define	ATTR_CTIME	AT_CTIME
 #define	ATTR_MTIME	AT_MTIME
 #define	ATTR_ATIME	AT_ATIME
+#if defined(_STANDALONE)
+#define	vmem_free kmem_free
+#define	vmem_zalloc kmem_zalloc
+#define	vmem_alloc kmem_zalloc
+#else
 #define	vmem_free zfs_kmem_free
 #define	vmem_zalloc(size, flags) zfs_kmem_alloc(size, flags | M_ZERO)
 #define	vmem_alloc zfs_kmem_alloc
+#endif
 #define	MUTEX_NOLOCKDEP 0
 #define	RW_NOLOCKDEP 0
 

sys/contrib/openzfs/include/os/freebsd/spl/sys/cmn_err.h

@@ -52,42 +52,33 @@ extern "C" {
 /*PRINTFLIKE2*/
 extern void cmn_err(int, const char *, ...)
     __KPRINTFLIKE(2);
-#pragma rarely_called(cmn_err)
 
 extern void vzcmn_err(zoneid_t, int, const char *, __va_list)
     __KVPRINTFLIKE(3);
-#pragma rarely_called(vzcmn_err)
 
 extern void vcmn_err(int, const char *, __va_list)
     __KVPRINTFLIKE(2);
-#pragma rarely_called(vcmn_err)
 
 /*PRINTFLIKE3*/
 extern void zcmn_err(zoneid_t, int, const char *, ...)
     __KPRINTFLIKE(3);
-#pragma rarely_called(zcmn_err)
 
 extern void vzprintf(zoneid_t, const char *, __va_list)
     __KVPRINTFLIKE(2);
-#pragma rarely_called(vzprintf)
 
 /*PRINTFLIKE2*/
 extern void zprintf(zoneid_t, const char *, ...)
     __KPRINTFLIKE(2);
-#pragma rarely_called(zprintf)
 
 extern void vuprintf(const char *, __va_list)
     __KVPRINTFLIKE(1);
-#pragma rarely_called(vuprintf)
 
 /*PRINTFLIKE1*/
 extern void panic(const char *, ...)
     __KPRINTFLIKE(1) __NORETURN;
-#pragma rarely_called(panic)
 
 extern void vpanic(const char *, __va_list)
     __KVPRINTFLIKE(1) __NORETURN;
-#pragma rarely_called(vpanic)
 
 #endif /* !_ASM */
 

sys/contrib/openzfs/include/os/freebsd/spl/sys/condvar.h

@@ -36,6 +36,7 @@
 #include <sys/spl_condvar.h>
 #include <sys/mutex.h>
 #include <sys/time.h>
+#include <sys/errno.h>
 
 /*
  * cv_timedwait() is similar to cv_wait() except that it additionally expects

sys/contrib/openzfs/include/os/freebsd/spl/sys/kmem.h

@@ -29,6 +29,7 @@
 #ifndef _OPENSOLARIS_SYS_KMEM_H_
 #define	_OPENSOLARIS_SYS_KMEM_H_
 
+#ifdef _KERNEL
 #include <sys/param.h>
 #include <sys/malloc.h>
 #include <sys/vmem.h>
@@ -93,5 +94,14 @@ void *calloc(size_t n, size_t s);
 	zfs_kmem_alloc((size), (kmflags) | M_ZERO)
 #define	kmem_free(buf, size)		zfs_kmem_free((buf), (size))
 
+#endif	/* _KERNEL */
+
+#ifdef _STANDALONE
+/*
+ * At the moment, we just need it for the type. We redirect the alloc/free
+ * routines to the usual Free and Malloc in that environment.
+ */
+typedef int kmem_cache_t;
+#endif /* _STANDALONE */
 
 #endif	/* _OPENSOLARIS_SYS_KMEM_H_ */

sys/contrib/openzfs/include/os/freebsd/spl/sys/kmem_cache.h

@@ -30,6 +30,7 @@
 #ifndef _SPL_KMEM_CACHE_H
 #define	_SPL_KMEM_CACHE_H
 
+#ifdef _KERNEL
 #include <sys/taskq.h>
 
 /* kmem move callback return values */
@@ -46,4 +47,6 @@ extern void spl_kmem_cache_set_move(kmem_cache_t *,
 
 #define	kmem_cache_set_move(skc, move)	spl_kmem_cache_set_move(skc, move)
 
+#endif /* _KERNEL */
+
 #endif

sys/contrib/openzfs/include/os/freebsd/spl/sys/kstat.h

@@ -24,8 +24,11 @@
 
 #ifndef _SPL_KSTAT_H
 #define	_SPL_KSTAT_H
+
 #include <sys/types.h>
+#ifndef _STANDALONE
 #include <sys/sysctl.h>
+#endif
 struct list_head {};
 #include <sys/mutex.h>
 #include <sys/proc.h>
@@ -129,9 +132,10 @@ struct kstat_s {
 	kstat_raw_ops_t	ks_raw_ops;		/* ops table for raw type */
 	char		*ks_raw_buf;		/* buf used for raw ops */
 	size_t		ks_raw_bufsize;		/* size of raw ops buffer */
+#ifndef _STANDALONE
 	struct sysctl_ctx_list ks_sysctl_ctx;
 	struct sysctl_oid *ks_sysctl_root;
-
+#endif /* _STANDALONE */
 };
 
 typedef struct kstat_named_s {
@@ -216,10 +220,16 @@ extern void kstat_runq_exit(kstat_io_t *);
     __kstat_set_seq_raw_ops(k, h, d, a)
 #define	kstat_set_raw_ops(k, h, d, a) \
     __kstat_set_raw_ops(k, h, d, a)
+#ifndef _STANDALONE
 #define	kstat_create(m, i, n, c, t, s, f) \
     __kstat_create(m, i, n, c, t, s, f)
 
 #define	kstat_install(k)		__kstat_install(k)
 #define	kstat_delete(k)			__kstat_delete(k)
+#else
+#define	kstat_create(m, i, n, c, t, s, f)	((kstat_t *)0)
+#define	kstat_install(k)
+#define	kstat_delete(k)
+#endif
 
 #endif  /* _SPL_KSTAT_H */

sys/contrib/openzfs/include/os/freebsd/spl/sys/proc.h

@@ -41,7 +41,7 @@
 #include <sys/kmem.h>
 #include <sys/malloc.h>
 
-
+#ifdef _KERNEL
 #define	CPU		curcpu
 #define	minclsyspri	PRIBIO
 #define	defclsyspri minclsyspri
@@ -111,4 +111,5 @@ zfs_proc_is_caller(proc_t *p)
 	return (p == curproc);
 }
 
+#endif	/* _KERNEL */
 #endif	/* _OPENSOLARIS_SYS_PROC_H_ */

sys/contrib/openzfs/include/os/freebsd/spl/sys/procfs_list.h

@@ -25,6 +25,8 @@
 #ifndef	_SPL_PROCFS_LIST_H
 #define	_SPL_PROCFS_LIST_H
 
+#ifndef _STANDALONE
+
 #include <sys/kstat.h>
 #include <sys/mutex.h>
 
@@ -64,4 +66,8 @@ void procfs_list_uninstall(procfs_list_t *procfs_list);
 void procfs_list_destroy(procfs_list_t *procfs_list);
 void procfs_list_add(procfs_list_t *procfs_list, void *p);
 
+#else
+typedef int procfs_list_t;
+#endif /* !_STANDALONE */
+
 #endif	/* _SPL_PROCFS_LIST_H */

sys/contrib/openzfs/include/os/freebsd/spl/sys/sig.h

@@ -29,6 +29,8 @@
 #ifndef _OPENSOLARIS_SYS_SIG_H_
 #define	_OPENSOLARIS_SYS_SIG_H_
 
+#ifndef _STANDALONE
+
 #include_next <sys/signal.h>
 #include <sys/param.h>
 #include <sys/lock.h>
@@ -62,4 +64,7 @@ issig(int why)
 	}
 	return (0);
 }
+
+#endif /* !_STANDALONE */
+
 #endif	/* _OPENSOLARIS_SYS_SIG_H_ */

sys/contrib/openzfs/include/os/freebsd/spl/sys/sysmacros.h

@@ -31,6 +31,7 @@
 #define	_SYS_SYSMACROS_H
 
 #include <sys/param.h>
+#include <sys/systm.h>
 #include <sys/isa_defs.h>
 #include <sys/libkern.h>
 #include <sys/zone.h>
@@ -71,7 +72,11 @@ extern "C" {
 #define	DIV_ROUND_UP(n, d)	(((n) + (d) - 1) / (d))
 #endif
 
+#ifdef _STANDALONE
+#define	boot_ncpus 1
+#else /* _STANDALONE */
 #define	boot_ncpus mp_ncpus
+#endif /* _STANDALONE */
 #define	kpreempt_disable() critical_enter()
 #define	kpreempt_enable() critical_exit()
 #define	CPU_SEQID curcpu
@@ -319,7 +324,7 @@ extern unsigned char bcd_to_byte[256];
 
 /* avoid any possibility of clashing with <stddef.h> version */
 
-#define	offsetof(s, m)	((size_t)(&(((s *)0)->m)))
+#define	offsetof(type, field)	__offsetof(type, field)
 #endif
 
 /*

sys/contrib/openzfs/include/os/freebsd/spl/sys/taskq.h

@@ -26,6 +26,8 @@
 #ifndef	_SYS_TASKQ_H
 #define	_SYS_TASKQ_H
 
+#ifdef _KERNEL
+
 #include <sys/types.h>
 #include <sys/proc.h>
 #include <sys/taskqueue.h>
@@ -112,4 +114,11 @@ void	taskq_resume(taskq_t *);
 }
 #endif
 
+#endif /* _KERNEL */
+
+#ifdef _STANDALONE
+typedef int taskq_ent_t;
+#define	taskq_init_ent(x)
+#endif /* _STANDALONE */
+
 #endif	/* _SYS_TASKQ_H */

sys/contrib/openzfs/include/os/freebsd/spl/sys/uio.h

@@ -29,6 +29,8 @@
 #ifndef _OPENSOLARIS_SYS_UIO_H_
 #define	_OPENSOLARIS_SYS_UIO_H_
 
+#ifndef _STANDALONE
+
 #include_next <sys/uio.h>
 #include <sys/_uio.h>
 #include <sys/debug.h>
@@ -107,4 +109,6 @@ uio_index_at_offset(uio_t *uio, offset_t off, uint_t *vec_idx)
 	return (off);
 }
 
+#endif /* !_STANDALONE */
+
 #endif	/* !_OPENSOLARIS_SYS_UIO_H_ */

sys/contrib/openzfs/include/sys/nvpair.h

@@ -62,7 +62,7 @@ typedef enum {
 	DATA_TYPE_UINT8,
 	DATA_TYPE_BOOLEAN_ARRAY,
 	DATA_TYPE_INT8_ARRAY,
-#if !defined(_KERNEL)
+#if !defined(_KERNEL) && !defined(_STANDALONE)
 	DATA_TYPE_UINT8_ARRAY,
 	DATA_TYPE_DOUBLE
 #else
@@ -191,7 +191,7 @@ int nvlist_add_uint64_array(nvlist_t *, const char *, uint64_t *, uint_t);
 int nvlist_add_string_array(nvlist_t *, const char *, char *const *, uint_t);
 int nvlist_add_nvlist_array(nvlist_t *, const char *, nvlist_t **, uint_t);
 int nvlist_add_hrtime(nvlist_t *, const char *, hrtime_t);
-#if !defined(_KERNEL)
+#if !defined(_KERNEL) && !defined(_STANDALONE)
 int nvlist_add_double(nvlist_t *, const char *, double);
 #endif
 
@@ -228,7 +228,7 @@ int nvlist_lookup_nvlist_array(nvlist_t *, const char *,
     nvlist_t ***, uint_t *);
 int nvlist_lookup_hrtime(nvlist_t *, const char *, hrtime_t *);
 int nvlist_lookup_pairs(nvlist_t *, int, ...);
-#if !defined(_KERNEL)
+#if !defined(_KERNEL) && !defined(_STANDALONE)
 int nvlist_lookup_double(nvlist_t *, const char *, double *);
 #endif
 
@@ -269,7 +269,7 @@ int nvpair_value_uint64_array(nvpair_t *, uint64_t **, uint_t *);
 int nvpair_value_string_array(nvpair_t *, char ***, uint_t *);
 int nvpair_value_nvlist_array(nvpair_t *, nvlist_t ***, uint_t *);
 int nvpair_value_hrtime(nvpair_t *, hrtime_t *);
-#if !defined(_KERNEL)
+#if !defined(_KERNEL) && !defined(_STANDALONE)
 int nvpair_value_double(nvpair_t *, double *);
 #endif
 

sys/contrib/openzfs/include/sys/zfs_context.h

@@ -32,7 +32,15 @@
 extern "C" {
 #endif
 
-#ifdef __KERNEL__
+/*
+ * This code compiles in three different contexts. When __KERNEL__ is defined,
+ * the code uses "unix-like" kernel interfaces. When _STANDALONE is defined, the
+ * code is running in a reduced capacity environment of the boot loader which is
+ * generally a subset of both POSIX and kernel interfaces (with a few unique
+ * interfaces too). When neither are defined, it's in a userland POSIX or
+ * similar environment.
+ */
+#if defined(__KERNEL__) || defined(_STANDALONE)
 #include <sys/note.h>
 #include <sys/types.h>
 #include <sys/atomic.h>
@@ -65,7 +73,7 @@ extern "C" {
 #include <sys/procfs_list.h>
 #include <sys/mod.h>
 #include <sys/zfs_context_os.h>
-#else /* _KERNEL */
+#else /* _KERNEL || _STANDALONE */
 
 #define	_SYS_MUTEX_H
 #define	_SYS_RWLOCK_H
@@ -759,7 +767,7 @@ extern int kmem_cache_reap_active(void);
 #define	__init
 #define	__exit
 
-#endif /* _KERNEL */
+#endif  /* _KERNEL || _STANDALONE */
 
 #ifdef __cplusplus
 };

sys/contrib/openzfs/lib/libspl/include/os/freebsd/sys/param.h

@@ -45,10 +45,6 @@
  */
 #define	MAXNAMELEN	256
 
-#ifndef IN_BASE
-#define	UID_NOBODY	60001		/* user ID no body */
-#define	GID_NOBODY	UID_NOBODY
-#endif
 #define	UID_NOACCESS	60002		/* user ID no access */
 
 #define	MAXUID		UINT32_MAX	/* max user id */

sys/contrib/openzfs/module/os/freebsd/spl/list.c

@@ -27,10 +27,10 @@
  * Generic doubly-linked list implementation
  */
 
+#include <sys/param.h>
 #include <sys/list.h>
 #include <sys/list_impl.h>
 #include <sys/types.h>
-#include <sys/sysmacros.h>
 #include <sys/debug.h>
 
 #define	list_d2l(a, obj) ((list_node_t *)(((char *)obj) + (a)->list_offset))