NetBSD-5.0.2/sys/compat/linux/arch/i386/linux_exec_machdep.c
/* $NetBSD: linux_exec_machdep.c,v 1.11.4.1 2009/04/01 00:25:22 snj Exp $ */
/*-
* Copyright (c) 2004 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
__KERNEL_RCSID(0, "$NetBSD: linux_exec_machdep.c,v 1.11.4.1 2009/04/01 00:25:22 snj Exp $");
#if defined(_KERNEL_OPT)
#include "opt_vm86.h"
#include "opt_user_ldt.h"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/resource.h>
#include <sys/proc.h>
#include <sys/conf.h>
#include <sys/exec.h>
#include <sys/exec_elf.h>
#include <sys/vnode.h>
#include <sys/lwp.h>
#include <sys/cpu.h>
#include <machine/vmparam.h>
#include <uvm/uvm.h>
#include <sys/syscallargs.h>
#ifndef DEBUG_LINUX
#define DPRINTF(a)
#else
#define DPRINTF(a) uprintf a
#endif
#include <compat/linux/common/linux_types.h>
#include <compat/linux/common/linux_signal.h>
#include <compat/linux/common/linux_machdep.h>
#include <compat/linux/common/linux_util.h>
#include <compat/linux/common/linux_ioctl.h>
#include <compat/linux/common/linux_hdio.h>
#include <compat/linux/common/linux_exec.h>
#include <compat/linux/common/linux_errno.h>
#include <compat/linux//linux_syscallargs.h>
int
linux_exec_setup_stack(struct lwp *l, struct exec_package *epp)
{
u_long max_stack_size;
u_long access_linear_min, access_size;
u_long noaccess_linear_min, noaccess_size;
#ifndef USRSTACK32
#define USRSTACK32 (0x00000000ffffffffL&~PGOFSET)
#endif
if (epp->ep_flags & EXEC_32) {
epp->ep_minsaddr = USRSTACK32;
max_stack_size = MAXSSIZ;
} else {
epp->ep_minsaddr = USRSTACK;
max_stack_size = MAXSSIZ;
}
if (epp->ep_minsaddr > LINUX_USRSTACK)
epp->ep_minsaddr = LINUX_USRSTACK;
#ifdef DEBUG_LINUX
else {
/*
* Someone needs to make KERNBASE and TEXTADDR
* java versions < 1.4.2 need the stack to be
* at 0xC0000000
*/
uprintf("Cannot setup stack to 0xC0000000, "
"java will not work properly\n");
}
#endif
epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr,
max_stack_size);
epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur;
/*
* set up commands for stack. note that this takes *two*, one to
* map the part of the stack which we can access, and one to map
* the part which we can't.
*
* arguably, it could be made into one, but that would require the
* addition of another mapping proc, which is unnecessary
*/
access_size = epp->ep_ssize;
access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size);
noaccess_size = max_stack_size - access_size;
noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr,
access_size), noaccess_size);
if (noaccess_size > 0) {
NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size,
noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK);
}
KASSERT(access_size > 0);
NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size,
access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE,
VMCMD_STACK);
return 0;
}
#ifdef LINUX_NPTL
static __inline void
load_gs(u_int sel)
{
__asm __volatile("movl %0,%%gs" : : "rm" (sel));
}
int
linux_init_thread_area(struct lwp *l, struct lwp *l2)
{
struct trapframe *tf = l->l_md.md_regs, *tf2 = l2->l_md.md_regs;
struct pcb *pcb2 = &l2->l_addr->u_pcb;
struct linux_user_desc info;
struct segment_descriptor sd;
int error, idx, a[2];
error = copyin((void *)tf->tf_esi, &info, sizeof(info));
if (error)
return error;
idx = info.entry_number;
/*
* looks like we're getting the idx we returned
* in the set_thread_area() syscall
*/
if (idx != LINUX_GLIBC_TLS_SEL && idx != GUGS_SEL) {
DPRINTF(("resetting idx %d to GUGS_SEL", idx));
idx = GUGS_SEL;
}
/* this doesnt happen in practice */
if (idx == LINUX_GLIBC_TLS_SEL) {
/* we might copy out the entry_number as 3 */
info.entry_number = GUGS_SEL;
error = copyout(&info, (void *)tf->tf_esi, sizeof(info));
if (error)
return error;
}
a[0] = LINUX_LDT_entry_a(&info);
a[1] = LINUX_LDT_entry_b(&info);
(void)memcpy(&sd, &a, sizeof(a));
KASSERT(ISMEMSDP((&sd)));
DPRINTF(("Segment created in clone with CLONE_SETTLS: lobase: %x, "
"hibase: %x, lolimit: %x, hilimit: %x, type: %i, dpl: %i, p: %i, "
"xx: %i, def32: %i, gran: %i\n", sd.sd_lobase,
sd.sd_hibase, sd.sd_lolimit, sd.sd_hilimit, sd.sd_type, sd.sd_dpl,
sd.sd_p, sd.sd_xx, sd.sd_def32, sd.sd_gran));
(void)memcpy(&pcb2->pcb_gsd, &sd, sizeof(sd));
tf2->tf_gs = GSEL(GUGS_SEL, SEL_UPL);
return 0;
}
int
linux_sys_set_thread_area(struct lwp *l,
const struct linux_sys_set_thread_area_args *uap, register_t *retval)
{
struct pcb *pcb = &l->l_addr->u_pcb;
struct linux_user_desc info;
struct segment_descriptor sd;
int error, idx, a[2];
*retval = 0;
error = copyin(SCARG(uap, desc), &info, sizeof(info));
if (error)
return error;
DPRINTF(("set thread area: %i, %x, %x, %i, %i, %i, %i, %i, %i\n",
info.entry_number, info.base_addr, info.limit, info.seg_32bit,
info.contents, info.read_exec_only, info.limit_in_pages,
info.seg_not_present, info.useable));
idx = info.entry_number;
/*
* Semantics of linux version: every thread in the system has array of
* 3 tls descriptors. 1st is GLIBC TLS, 2nd is WINE, 3rd unknown. This
* syscall loads one of the selected tls decriptors with a value and
* also loads GDT descriptors 6, 7 and 8 with the content of the
* per-thread descriptors.
*
* Semantics of fbsd version: I think we can ignore that linux has 3
* per-thread descriptors and use just the 1st one. The tls_array[]
* is used only in set/get-thread_area() syscalls and for loading the
* GDT descriptors. In fbsd we use just one GDT descriptor for TLS so
* we will load just one.
*
* XXX: this doesn't work when a user space process tries to use more
* than 1 TLS segment. Comment in the linux sources says wine might do
* this.
*/
/*
* we support just GLIBC TLS now
* we should let 3 proceed as well because we use this segment so
* if code does two subsequent calls it should succeed
*/
if (idx != LINUX_GLIBC_TLS_SEL && idx != -1 && idx != GUGS_SEL)
return EINVAL;
/*
* we have to copy out the GDT entry we use
* FreeBSD uses GDT entry #3 for storing %gs so load that
*
* XXX: what if a user space program doesn't check this value and tries
* to use 6, 7 or 8?
*/
idx = info.entry_number = GUGS_SEL;
error = copyout(&info, SCARG(uap, desc), sizeof(info));
if (error)
return error;
if (LINUX_LDT_empty(&info)) {
a[0] = 0;
a[1] = 0;
} else {
a[0] = LINUX_LDT_entry_a(&info);
a[1] = LINUX_LDT_entry_b(&info);
}
(void)memcpy(&sd, &a, sizeof(a));
KASSERT(ISMEMSDP((&sd)));
DPRINTF(("Segment created in set_thread_area: lobase: %x, hibase: %x, "
"lolimit: %x, hilimit: %x, type: %i, dpl: %i, p: %i, xx: %i, "
"def32: %i, gran: %i\n", sd.sd_lobase, sd.sd_hibase, sd.sd_lolimit,
sd.sd_hilimit, sd.sd_type, sd.sd_dpl, sd.sd_p, sd.sd_xx,
sd.sd_def32, sd.sd_gran));
kpreempt_disable();
(void)memcpy(&pcb->pcb_gsd, &sd, sizeof(sd));
(void)memcpy(&curcpu()->ci_gdt[GUGS_SEL], &sd, sizeof(sd));
load_gs(GSEL(GUGS_SEL, SEL_UPL));
kpreempt_enable();
return 0;
}
int
linux_sys_get_thread_area(struct lwp *l,
const struct linux_sys_get_thread_area_args *uap, register_t *retval)
{
struct pcb *pcb = &l->l_addr->u_pcb;
struct linux_user_desc info;
struct linux_desc_struct desc;
struct segment_descriptor sd;
int error, idx;
*retval = 0;
error = copyin(SCARG(uap, desc), &info, sizeof(info));
if (error)
return error;
idx = info.entry_number;
/* XXX: I am not sure if we want 3 to be allowed too. */
if (idx != LINUX_GLIBC_TLS_SEL && idx != GUGS_SEL)
return EINVAL;
idx = GUGS_SEL;
(void)memset(&info, 0, sizeof(info));
(void)memcpy(&sd, pcb->pcb_gsd, sizeof(sd));
(void)memcpy(&desc, &sd, sizeof(desc));
info.entry_number = idx;
info.base_addr = LINUX_GET_BASE(&desc);
info.limit = LINUX_GET_LIMIT(&desc);
info.seg_32bit = LINUX_GET_32BIT(&desc);
info.contents = LINUX_GET_CONTENTS(&desc);
info.read_exec_only = !LINUX_GET_WRITABLE(&desc);
info.limit_in_pages = LINUX_GET_LIMIT_PAGES(&desc);
info.seg_not_present = !LINUX_GET_PRESENT(&desc);
info.useable = LINUX_GET_USEABLE(&desc);
return copyout(&info, SCARG(uap, desc), sizeof(info));
}
#endif