1/*	$NetBSD: linux_exec_machdep.c,v 1.16 2010/07/07 01:30:34 chs Exp $	*/
2
3/*-
4 * Copyright (c) 2004 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Christos Zoulas.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__KERNEL_RCSID(0, "$NetBSD: linux_exec_machdep.c,v 1.16 2010/07/07 01:30:34 chs Exp $");
34
35#if defined(_KERNEL_OPT)
36#include "opt_vm86.h"
37#include "opt_user_ldt.h"
38#endif
39
40#include <sys/param.h>
41#include <sys/systm.h>
42#include <sys/resource.h>
43#include <sys/proc.h>
44#include <sys/conf.h>
45#include <sys/exec.h>
46#include <sys/exec_elf.h>
47#include <sys/vnode.h>
48#include <sys/lwp.h>
49
50#include <sys/cpu.h>
51#include <machine/vmparam.h>
52
53#include <uvm/uvm.h>
54
55#include <sys/syscallargs.h>
56
57#ifndef DEBUG_LINUX
58#define DPRINTF(a)
59#else
60#define DPRINTF(a)	uprintf a
61#endif
62
63#include <compat/linux/common/linux_types.h>
64#include <compat/linux/common/linux_signal.h>
65#include <compat/linux/common/linux_machdep.h>
66#include <compat/linux/common/linux_util.h>
67#include <compat/linux/common/linux_ioctl.h>
68#include <compat/linux/common/linux_hdio.h>
69#include <compat/linux/common/linux_exec.h>
70#include <compat/linux/common/linux_errno.h>
71#include <compat/linux/linux_syscallargs.h>
72
73int
74linux_exec_setup_stack(struct lwp *l, struct exec_package *epp)
75{
76	u_long max_stack_size;
77	u_long access_linear_min, access_size;
78	u_long noaccess_linear_min, noaccess_size;
79
80#ifndef	USRSTACK32
81#define USRSTACK32	(0x00000000ffffffffL&~PGOFSET)
82#endif
83
84	if (epp->ep_flags & EXEC_32) {
85		epp->ep_minsaddr = USRSTACK32;
86		max_stack_size = MAXSSIZ;
87	} else {
88		epp->ep_minsaddr = USRSTACK;
89		max_stack_size = MAXSSIZ;
90	}
91
92	if (epp->ep_minsaddr > LINUX_USRSTACK)
93		epp->ep_minsaddr = LINUX_USRSTACK;
94#ifdef DEBUG_LINUX
95	else {
96		/*
97		 * Someone needs to make KERNBASE and TEXTADDR
98		 * java versions < 1.4.2 need the stack to be
99		 * at 0xC0000000
100		 */
101		uprintf("Cannot setup stack to 0xC0000000, "
102		    "java will not work properly\n");
103	}
104#endif
105	epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr,
106		max_stack_size);
107	epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur;
108
109	/*
110	 * set up commands for stack.  note that this takes *two*, one to
111	 * map the part of the stack which we can access, and one to map
112	 * the part which we can't.
113	 *
114	 * arguably, it could be made into one, but that would require the
115	 * addition of another mapping proc, which is unnecessary
116	 */
117	access_size = epp->ep_ssize;
118	access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size);
119	noaccess_size = max_stack_size - access_size;
120	noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr,
121	    access_size), noaccess_size);
122	if (noaccess_size > 0) {
123		NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size,
124		    noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK);
125	}
126	KASSERT(access_size > 0);
127	NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size,
128	    access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE,
129	    VMCMD_STACK);
130
131	return 0;
132}
133
134int
135linux_sys_set_thread_area(struct lwp *l,
136    const struct linux_sys_set_thread_area_args *uap, register_t *retval)
137{
138	/* {
139		syscallarg(struct linux_user_desc *) desc;
140	} */
141
142	return linux_lwp_setprivate(l, SCARG(uap, desc));
143}
144
145int
146linux_sys_get_thread_area(struct lwp *l,
147    const struct linux_sys_get_thread_area_args *uap, register_t *retval)
148{
149	/* {
150		syscallarg(struct linux_user_desc *) desc;
151	} */
152
153	/* glibc doesn't actually call this. */
154	return ENOSYS;
155}
156