libzfs_compat.c revision 322079 
1227935Sfjoe/*
2227935Sfjoe * CDDL HEADER SART
3227935Sfjoe *
4227935Sfjoe * The contents of this file are subject to the terms of the
5227935Sfjoe * Common Development and Distribution License (the "License").
6227935Sfjoe * You may not use this file except in compliance with the License.
7227935Sfjoe *
8227935Sfjoe * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9227935Sfjoe * or http://www.opensolaris.org/os/licensing.
10227935Sfjoe * See the License for the specific language governing permissions
11227935Sfjoe * and limitations under the License.
12227935Sfjoe *
13227935Sfjoe * When distributing Covered Code, include this CDDL HEADER in each
14227935Sfjoe * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15227935Sfjoe * If applicable, add the following below this CDDL HEADER, with the
16227935Sfjoe * fields enclosed by brackets "[]" replaced with your own identifying
17227935Sfjoe * information: Portions Copyright [yyyy] [name of copyright owner]
18227935Sfjoe *
19227935Sfjoe * CDDL HEADER END
20227935Sfjoe */
21227935Sfjoe
22227935Sfjoe/*
23227935Sfjoe * Copyright (c) 2013 Martin Matuska <mm@FreeBSD.org>. All rights reserved.
24227935Sfjoe */
25227935Sfjoe
26227935Sfjoe#include "libzfs_compat.h"
27227935Sfjoe
28227935Sfjoeint zfs_ioctl_version = ZFS_IOCVER_UNDEF;
29227935Sfjoestatic int zfs_spa_version = -1;
30227935Sfjoe
31227935Sfjoe/*
32227935Sfjoe * Get zfs_ioctl_version
33227935Sfjoe */
34227935Sfjoeint
35227935Sfjoeget_zfs_ioctl_version(void)
36227935Sfjoe{
37227935Sfjoe	size_t ver_size;
38227935Sfjoe	int ver = ZFS_IOCVER_NONE;
39227935Sfjoe
40228066Sfjoe	ver_size = sizeof(ver);
41228066Sfjoe	sysctlbyname("vfs.zfs.version.ioctl", &ver, &ver_size, NULL, 0);
42227935Sfjoe
43227935Sfjoe	return (ver);
44227935Sfjoe}
45227935Sfjoe
46227935Sfjoe/*
47227935Sfjoe * Get the SPA version
48227935Sfjoe */
49227935Sfjoestatic int
50227935Sfjoeget_zfs_spa_version(void)
51227935Sfjoe{
52227935Sfjoe	size_t ver_size;
53227935Sfjoe	int ver = 0;
54227935Sfjoe
55227935Sfjoe	ver_size = sizeof(ver);
56227935Sfjoe	sysctlbyname("vfs.zfs.version.spa", &ver, &ver_size, NULL, 0);
57227935Sfjoe
58227937Sfjoe	return (ver);
59227935Sfjoe}
60227935Sfjoe
61227935Sfjoe/*
62 * This is FreeBSD version of ioctl, because Solaris' ioctl() updates
63 * zc_nvlist_dst_size even if an error is returned, on FreeBSD if an
64 * error is returned zc_nvlist_dst_size won't be updated.
65 */
66int
67zcmd_ioctl(int fd, int request, zfs_cmd_t *zc)
68{
69	size_t oldsize;
70	int ret, cflag = ZFS_CMD_COMPAT_NONE;
71
72	if (zfs_ioctl_version == ZFS_IOCVER_UNDEF)
73		zfs_ioctl_version = get_zfs_ioctl_version();
74
75	if (zfs_ioctl_version >= ZFS_IOCVER_DEADMAN) {
76		switch (zfs_ioctl_version) {
77		case ZFS_IOCVER_INLANES:
78			cflag = ZFS_CMD_COMPAT_INLANES;
79			break;
80		case ZFS_IOCVER_RESUME:
81			cflag = ZFS_CMD_COMPAT_RESUME;
82			break;
83		case ZFS_IOCVER_EDBP:
84			cflag = ZFS_CMD_COMPAT_EDBP;
85			break;
86		case ZFS_IOCVER_ZCMD:
87			cflag = ZFS_CMD_COMPAT_ZCMD;
88			break;
89		case ZFS_IOCVER_LZC:
90			cflag = ZFS_CMD_COMPAT_LZC;
91			break;
92		case ZFS_IOCVER_DEADMAN:
93			cflag = ZFS_CMD_COMPAT_DEADMAN;
94			break;
95		}
96	} else {
97		/*
98		 * If vfs.zfs.version.ioctl is not defined, assume we have v28
99		 * compatible binaries and use vfs.zfs.version.spa to test for v15
100		 */
101		cflag = ZFS_CMD_COMPAT_V28;
102
103		if (zfs_spa_version < 0)
104			zfs_spa_version = get_zfs_spa_version();
105
106		if (zfs_spa_version == SPA_VERSION_15 ||
107		    zfs_spa_version == SPA_VERSION_14 ||
108		    zfs_spa_version == SPA_VERSION_13)
109			cflag = ZFS_CMD_COMPAT_V15;
110	}
111
112	oldsize = zc->zc_nvlist_dst_size;
113	ret = zcmd_ioctl_compat(fd, request, zc, cflag);
114
115	if (ret == 0 && oldsize < zc->zc_nvlist_dst_size) {
116		ret = -1;
117		errno = ENOMEM;
118	}
119
120	return (ret);
121}
122