zfs-builds-mm/zfs-2.0.0-rc6/lib/libzutil/os/freebsd/zutil_compat.c
2020-11-15 11:35:49 +01:00

124 lines
3 KiB
C

/*
* 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
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/zfs_ioctl.h>
#include <os/freebsd/zfs/sys/zfs_ioctl_compat.h>
#include <libzutil.h>
#include <err.h>
int zfs_ioctl_version = ZFS_IOCVER_UNDEF;
/*
* Get zfs_ioctl_version
*/
static int
get_zfs_ioctl_version(void)
{
size_t ver_size;
int ver = ZFS_IOCVER_NONE;
ver_size = sizeof (ver);
sysctlbyname("vfs.zfs.version.ioctl", &ver, &ver_size, NULL, 0);
return (ver);
}
static int
zcmd_ioctl_compat(int fd, int request, zfs_cmd_t *zc, const int cflag)
{
int newrequest, ret;
void *zc_c = NULL;
unsigned long ncmd;
zfs_iocparm_t zp;
switch (cflag) {
case ZFS_CMD_COMPAT_NONE:
ncmd = _IOWR('Z', request, zfs_iocparm_t);
zp.zfs_cmd = (uint64_t)(uintptr_t)zc;
zp.zfs_cmd_size = sizeof (zfs_cmd_t);
zp.zfs_ioctl_version = ZFS_IOCVER_OZFS;
break;
case ZFS_CMD_COMPAT_LEGACY:
newrequest = zfs_ioctl_ozfs_to_legacy(request);
ncmd = _IOWR('Z', newrequest, zfs_iocparm_t);
zc_c = malloc(sizeof (zfs_cmd_legacy_t));
zfs_cmd_ozfs_to_legacy(zc, zc_c);
zp.zfs_cmd = (uint64_t)(uintptr_t)zc_c;
zp.zfs_cmd_size = sizeof (zfs_cmd_legacy_t);
zp.zfs_ioctl_version = ZFS_IOCVER_LEGACY;
break;
default:
abort();
return (EINVAL);
}
ret = ioctl(fd, ncmd, &zp);
if (ret) {
if (zc_c)
free(zc_c);
return (ret);
}
if (zc_c) {
zfs_cmd_legacy_to_ozfs(zc_c, zc);
free(zc_c);
}
return (ret);
}
/*
* This is FreeBSD version of ioctl, because Solaris' ioctl() updates
* zc_nvlist_dst_size even if an error is returned, on FreeBSD if an
* error is returned zc_nvlist_dst_size won't be updated.
*/
int
zfs_ioctl_fd(int fd, unsigned long request, zfs_cmd_t *zc)
{
size_t oldsize;
int ret, cflag = ZFS_CMD_COMPAT_NONE;
if (zfs_ioctl_version == ZFS_IOCVER_UNDEF)
zfs_ioctl_version = get_zfs_ioctl_version();
switch (zfs_ioctl_version) {
case ZFS_IOCVER_LEGACY:
cflag = ZFS_CMD_COMPAT_LEGACY;
break;
case ZFS_IOCVER_OZFS:
cflag = ZFS_CMD_COMPAT_NONE;
break;
default:
errx(1, "unrecognized zfs ioctl version %d",
zfs_ioctl_version);
}
oldsize = zc->zc_nvlist_dst_size;
ret = zcmd_ioctl_compat(fd, request, zc, cflag);
if (ret == 0 && oldsize < zc->zc_nvlist_dst_size) {
ret = -1;
errno = ENOMEM;
}
return (ret);
}