xref: /netbsd-src/sys/compat/linux/arch/i386/linux_exec_machdep.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: linux_exec_machdep.c,v 1.19 2020/07/19 13:55:08 maxv 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 1.19 2020/07/19 13:55:08 maxv Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/resource.h>
38 #include <sys/proc.h>
39 #include <sys/conf.h>
40 #include <sys/exec.h>
41 #include <sys/exec_elf.h>
42 #include <sys/vnode.h>
43 #include <sys/lwp.h>
44 
45 #include <sys/cpu.h>
46 #include <machine/vmparam.h>
47 
48 #include <uvm/uvm.h>
49 
50 #include <sys/syscallargs.h>
51 
52 #ifndef DEBUG_LINUX
53 #define DPRINTF(a)
54 #else
55 #define DPRINTF(a)	uprintf a
56 #endif
57 
58 #include <compat/linux/common/linux_types.h>
59 #include <compat/linux/common/linux_signal.h>
60 #include <compat/linux/common/linux_machdep.h>
61 #include <compat/linux/common/linux_util.h>
62 #include <compat/linux/common/linux_ioctl.h>
63 #include <compat/linux/common/linux_hdio.h>
64 #include <compat/linux/common/linux_exec.h>
65 #include <compat/linux/common/linux_errno.h>
66 #include <compat/linux/linux_syscallargs.h>
67 
68 int
69 linux_exec_setup_stack(struct lwp *l, struct exec_package *epp)
70 {
71 	u_long max_stack_size;
72 	u_long access_linear_min, access_size;
73 	u_long noaccess_linear_min, noaccess_size;
74 
75 #ifndef	USRSTACK32
76 #define USRSTACK32	(0x00000000ffffffffL&~PGOFSET)
77 #endif
78 
79 	if (epp->ep_flags & EXEC_32) {
80 		epp->ep_minsaddr = USRSTACK32;
81 		max_stack_size = MAXSSIZ;
82 	} else {
83 		epp->ep_minsaddr = USRSTACK;
84 		max_stack_size = MAXSSIZ;
85 	}
86 
87 	if (epp->ep_minsaddr > LINUX_USRSTACK)
88 		epp->ep_minsaddr = LINUX_USRSTACK;
89 #ifdef DEBUG_LINUX
90 	else {
91 		/*
92 		 * Someone needs to make KERNBASE and TEXTADDR
93 		 * java versions < 1.4.2 need the stack to be
94 		 * at 0xC0000000
95 		 */
96 		uprintf("Cannot setup stack to 0xC0000000, "
97 		    "java will not work properly\n");
98 	}
99 #endif
100 	epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr,
101 		max_stack_size);
102 	epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur;
103 
104 	/*
105 	 * set up commands for stack.  note that this takes *two*, one to
106 	 * map the part of the stack which we can access, and one to map
107 	 * the part which we can't.
108 	 *
109 	 * arguably, it could be made into one, but that would require the
110 	 * addition of another mapping proc, which is unnecessary
111 	 */
112 	access_size = epp->ep_ssize;
113 	access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size);
114 	noaccess_size = max_stack_size - access_size;
115 	noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr,
116 	    access_size), noaccess_size);
117 	if (noaccess_size > 0) {
118 		NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size,
119 		    noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK);
120 	}
121 	KASSERT(access_size > 0);
122 	NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size,
123 	    access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE,
124 	    VMCMD_STACK);
125 
126 	return 0;
127 }
128 
129 int
130 linux_sys_set_thread_area(struct lwp *l,
131     const struct linux_sys_set_thread_area_args *uap, register_t *retval)
132 {
133 	/* {
134 		syscallarg(struct linux_user_desc *) desc;
135 	} */
136 
137 	return linux_lwp_setprivate(l, SCARG(uap, desc));
138 }
139 
140 int
141 linux_sys_get_thread_area(struct lwp *l,
142     const struct linux_sys_get_thread_area_args *uap, register_t *retval)
143 {
144 	/* {
145 		syscallarg(struct linux_user_desc *) desc;
146 	} */
147 
148 	/* glibc doesn't actually call this. */
149 	return ENOSYS;
150 }
151