xref: /netbsd-src/sys/compat/linux/arch/powerpc/linux_exec_powerpc.c (revision aa73cae19608873cc4d1f712c4a0f8f8435f1ffa)
1 /* $NetBSD: linux_exec_powerpc.c,v 1.16 2005/02/26 23:10:19 perry Exp $ */
2 
3 /*-
4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Emmanuel Dreyfus.
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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by the NetBSD
21  *      Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * From NetBSD's sys/compat/arch/alpha/linux_exec_alpha.c, with some
41  * powerpc add-ons (ifdef LINUX_SHIFT).
42  *
43  * This code is to be common to alpha and powerpc. If it works on alpha, it
44  * should be moved to common/linux_exec_elf32.c. Beware that it needs
45  * LINUX_ELF_AUX_ENTRIES in arch/<arch>/linux_exec.h to also be moved to common
46  *
47  * Emmanuel Dreyfus <p99dreyf@criens.u-psud.fr>
48  */
49 
50 #include <sys/cdefs.h>
51 __KERNEL_RCSID(0, "$NetBSD: linux_exec_powerpc.c,v 1.16 2005/02/26 23:10:19 perry Exp $");
52 
53 #if defined (__alpha__)
54 #define ELFSIZE 64
55 #elif defined (__powerpc__)
56 #define ELFSIZE 32
57 #else
58 #error Unified linux_elf_{32|64}copyargs not tested for this platform
59 #endif
60 
61 #include <sys/param.h>
62 #include <sys/systm.h>
63 #include <sys/kernel.h>
64 #include <sys/malloc.h>
65 #include <sys/proc.h>
66 #include <sys/exec.h>
67 #include <sys/exec_elf.h>
68 #include <sys/resourcevar.h>
69 
70 #include <uvm/uvm_extern.h>
71 
72 #include <compat/linux/common/linux_exec.h>
73 
74 /*
75  * Alpha and PowerPC specific linux copyargs function.
76  */
77 int
78 ELFNAME2(linux,copyargs)(p, pack, arginfo, stackp, argp)
79 	struct proc *p;
80 	struct exec_package *pack;
81 	struct ps_strings *arginfo;
82 	char **stackp;
83 	void *argp;
84 {
85 	size_t len;
86 	AuxInfo ai[LINUX_ELF_AUX_ENTRIES], *a;
87 	struct elf_args *ap;
88 	int error;
89 
90 #ifdef LINUX_SHIFT
91 	/*
92 	 * Seems that PowerPC Linux binaries expect argc to start on a 16 bytes
93 	 * aligned address. And we need one more 16 byte shift if it was already
94 	 * 16 bytes aligned,
95 	 */
96 	*stackp = (char *)(((unsigned long)*stackp - 1) & ~LINUX_SHIFT);
97 #endif
98 
99 	if ((error = copyargs(p, pack, arginfo, stackp, argp)) != 0)
100 		return error;
101 
102 #ifdef LINUX_SHIFT
103 	/*
104 	 * From Linux's arch/ppc/kernel/process.c:shove_aux_table(). GNU ld.so
105 	 * expects the ELF auxiliary table to start on a 16 bytes boundary on
106 	 * the PowerPC.
107 	 */
108 	*stackp = (char *)(((unsigned long)(*stackp) + LINUX_SHIFT)
109 	    & ~LINUX_SHIFT);
110 #endif
111 
112 	memset(ai, 0, sizeof(AuxInfo) * LINUX_ELF_AUX_ENTRIES);
113 
114 	a = ai;
115 
116 	/*
117 	 * Push extra arguments on the stack needed by dynamically
118 	 * linked binaries.
119 	 */
120 	if ((ap = (struct elf_args *)pack->ep_emul_arg)) {
121 #if 1
122 		/*
123 		 * The exec_package doesn't have a proc pointer and it's not
124 		 * exactly trivial to add one since the credentials are
125 		 * changing. XXX Linux uses curlwp's credentials.
126 		 * Why can't we use them too?
127 		 */
128 		a->a_type = LINUX_AT_EGID;
129 		a->a_v = p->p_ucred->cr_gid;
130 		a++;
131 
132 		a->a_type = LINUX_AT_GID;
133 		a->a_v = p->p_cred->p_rgid;
134 		a++;
135 
136 		a->a_type = LINUX_AT_EUID;
137 		a->a_v = p->p_ucred->cr_uid;
138 		a++;
139 
140 		a->a_type = LINUX_AT_UID;
141 		a->a_v = p->p_cred->p_ruid;
142 		a++;
143 #endif
144 
145 		a->a_type = AT_ENTRY;
146 		a->a_v = ap->arg_entry;
147 		a++;
148 
149 		a->a_type = AT_FLAGS;
150 		a->a_v = 0;
151 		a++;
152 
153 		a->a_type = AT_BASE;
154 		a->a_v = ap->arg_interp;
155 		a++;
156 
157 		a->a_type = AT_PHNUM;
158 		a->a_v = ap->arg_phnum;
159 		a++;
160 
161 		a->a_type = AT_PHENT;
162 		a->a_v = ap->arg_phentsize;
163 		a++;
164 
165 		a->a_type = AT_PHDR;
166 		a->a_v = ap->arg_phaddr;
167 		a++;
168 
169 		a->a_type = LINUX_AT_CLKTCK;
170 		a->a_v = LINUX_CLOCKS_PER_SEC;
171 		a++;
172 
173 		a->a_type = AT_PAGESZ;
174 		a->a_v = PAGE_SIZE;
175 		a++;
176 
177 		a->a_type = LINUX_AT_HWCAP;
178 		a->a_v = LINUX_ELF_HWCAP;
179 		a++;
180 
181 		free((char *)ap, M_TEMP);
182 		pack->ep_emul_arg = NULL;
183 	}
184 
185 	a->a_type = AT_NULL;
186 	a->a_v = 0;
187 	a++;
188 
189 	len = (a - ai) * sizeof(AuxInfo);
190 
191 	if ((error = copyout(ai, *stackp, len)) != 0)
192 		return error;
193 	*stackp += len;
194 	return 0;
195 }
196