/*
* FreeBSD sysctl() and sysarch() system call emulation
*
* Copyright (c) 2013-15 Stacey D. Son
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see .
*/
#include "qemu/osdep.h"
#include "qemu.h"
#include "target_arch_sysarch.h"
#include
/*
* Length for the fixed length types.
* 0 means variable length for strings and structures
* Compare with sys/kern_sysctl.c ctl_size
* Note: Not all types appear to be used in-tree.
*/
static const int guest_ctl_size[CTLTYPE + 1] = {
[CTLTYPE_INT] = sizeof(abi_int),
[CTLTYPE_UINT] = sizeof(abi_uint),
[CTLTYPE_LONG] = sizeof(abi_long),
[CTLTYPE_ULONG] = sizeof(abi_ulong),
[CTLTYPE_S8] = sizeof(int8_t),
[CTLTYPE_S16] = sizeof(int16_t),
[CTLTYPE_S32] = sizeof(int32_t),
[CTLTYPE_S64] = sizeof(int64_t),
[CTLTYPE_U8] = sizeof(uint8_t),
[CTLTYPE_U16] = sizeof(uint16_t),
[CTLTYPE_U32] = sizeof(uint32_t),
[CTLTYPE_U64] = sizeof(uint64_t),
};
static const int host_ctl_size[CTLTYPE + 1] = {
[CTLTYPE_INT] = sizeof(int),
[CTLTYPE_UINT] = sizeof(u_int),
[CTLTYPE_LONG] = sizeof(long),
[CTLTYPE_ULONG] = sizeof(u_long),
[CTLTYPE_S8] = sizeof(int8_t),
[CTLTYPE_S16] = sizeof(int16_t),
[CTLTYPE_S32] = sizeof(int32_t),
[CTLTYPE_S64] = sizeof(int64_t),
[CTLTYPE_U8] = sizeof(uint8_t),
[CTLTYPE_U16] = sizeof(uint16_t),
[CTLTYPE_U32] = sizeof(uint32_t),
[CTLTYPE_U64] = sizeof(uint64_t),
};
#ifdef TARGET_ABI32
/*
* Limit the amount of available memory to be most of the 32-bit address
* space. 0x100c000 was arrived at through trial and error as a good
* definition of 'most'.
*/
static const abi_ulong guest_max_mem = UINT32_MAX - 0x100c000 + 1;
static abi_ulong G_GNUC_UNUSED cap_memory(uint64_t mem)
{
return MIN(guest_max_mem, mem);
}
#endif
static abi_ulong G_GNUC_UNUSED scale_to_guest_pages(uint64_t pages)
{
/* Scale pages from host to guest */
pages = muldiv64(pages, qemu_real_host_page_size(), TARGET_PAGE_SIZE);
#ifdef TARGET_ABI32
/* cap pages if need be */
pages = MIN(pages, guest_max_mem / (abi_ulong)TARGET_PAGE_SIZE);
#endif
return pages;
}
#ifdef TARGET_ABI32
/* Used only for TARGET_ABI32 */
static abi_long h2g_long_sat(long l)
{
if (l > INT32_MAX) {
l = INT32_MAX;
} else if (l < INT32_MIN) {
l = INT32_MIN;
}
return l;
}
static abi_ulong h2g_ulong_sat(u_long ul)
{
return MIN(ul, UINT32_MAX);
}
#endif
/*
* placeholder until bsd-user downstream upstreams this with its thread support
*/
#define bsd_get_ncpu() 1
/*
* This uses the undocumented oidfmt interface to find the kind of a requested
* sysctl, see /sys/kern/kern_sysctl.c:sysctl_sysctl_oidfmt() (compare to
* src/sbin/sysctl/sysctl.c)
*/
static int G_GNUC_UNUSED oidfmt(int *oid, int len, char *fmt, uint32_t *kind)
{
int qoid[CTL_MAXNAME + 2];
uint8_t buf[BUFSIZ];
int i;
size_t j;
qoid[0] = CTL_SYSCTL;
qoid[1] = CTL_SYSCTL_OIDFMT;
memcpy(qoid + 2, oid, len * sizeof(int));
j = sizeof(buf);
i = sysctl(qoid, len + 2, buf, &j, 0, 0);
if (i) {
return i;
}
if (kind) {
*kind = *(uint32_t *)buf;
}
if (fmt) {
strcpy(fmt, (char *)(buf + sizeof(uint32_t)));
}
return 0;
}
/*
* Convert the old value from host to guest.
*
* For LONG and ULONG on ABI32, we need to 'down convert' the 8 byte quantities
* to 4 bytes. The caller setup a buffer in host memory to get this data from
* the kernel and pass it to us. We do the down conversion and adjust the length
* so the caller knows what to write as the returned length into the target when
* it copies the down converted values into the target.
*
* For normal integral types, we just need to byte swap. No size changes.
*
* For strings and node data, there's no conversion needed.
*
* For opaque data, per sysctl OID converts take care of it.
*/
static void G_GNUC_UNUSED h2g_old_sysctl(void *holdp, size_t *holdlen, uint32_t kind)
{
size_t len;
int hlen, glen;
uint8_t *hp, *gp;
/*
* Although rare, we can have arrays of sysctl. Both sysctl_old_ddb in
* kern_sysctl.c and show_var in sbin/sysctl/sysctl.c have code that loops
* this way. *holdlen has been set by the kernel to the host's length.
* Only LONG and ULONG on ABI32 have different sizes: see below.
*/
gp = hp = (uint8_t *)holdp;
len = 0;
hlen = host_ctl_size[kind & CTLTYPE];
glen = guest_ctl_size[kind & CTLTYPE];
/*
* hlen == 0 for CTLTYPE_STRING and CTLTYPE_NODE, which need no conversion
* as well as CTLTYPE_OPAQUE, which needs special converters.
*/
if (hlen == 0) {
return;
}
while (len < *holdlen) {
if (hlen == glen) {
switch (hlen) {
case 1:
/* Nothing needed: no byteswapping and assigning in place */
break;
case 2:
*(uint16_t *)gp = tswap16(*(uint16_t *)hp);
break;
case 4:
*(uint32_t *)gp = tswap32(*(uint32_t *)hp);
break;
case 8:
*(uint64_t *)gp = tswap64(*(uint64_t *)hp);
break;
default:
g_assert_not_reached();
}
} else {
#ifdef TARGET_ABI32
/*
* Saturating assignment for the only two types that differ between
* 32-bit and 64-bit machines. All other integral types have the
* same, fixed size and will be converted w/o loss of precision
* in the above switch.
*/
switch (kind & CTLTYPE) {
case CTLTYPE_LONG:
*(abi_long *)gp = tswap32(h2g_long_sat(*(long *)hp));
break;
case CTLTYPE_ULONG:
*(abi_ulong *)gp = tswap32(h2g_ulong_sat(*(u_long *)hp));
break;
default:
g_assert_not_reached();
}
#else
g_assert_not_reached();
#endif
}
gp += glen;
hp += hlen;
len += hlen;
}
#ifdef TARGET_ABI32
if (hlen != glen) {
*holdlen = (*holdlen / hlen) * glen;
}
#endif
}
/* sysarch() is architecture dependent. */
abi_long do_freebsd_sysarch(void *cpu_env, abi_long arg1, abi_long arg2)
{
return do_freebsd_arch_sysarch(cpu_env, arg1, arg2);
}