xref: /netbsd-src/sys/compat/linux/arch/powerpc/linux_exec_powerpc.c (revision 1ffa7b76c40339c17a0fb2a09fac93f287cfc046)
1 /* $NetBSD: linux_exec_powerpc.c,v 1.10 2003/04/01 14:45:09 thorpej 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 and LINUX_SP_WRAP).
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 1.10 2003/04/01 14:45:09 thorpej 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 
69 #include <uvm/uvm_extern.h>
70 
71 #include <compat/linux/common/linux_exec.h>
72 
73 #ifdef LINUX_SP_WRAP
74 extern int linux_sp_wrap_start;
75 extern int linux_sp_wrap_end;
76 extern int linux_sp_wrap_entry;
77 #endif
78 /*
79  * Alpha and PowerPC specific linux copyargs function.
80  */
81 int
82 ELFNAME2(linux,copyargs)(p, pack, arginfo, stackp, argp)
83 	struct proc *p;
84 	struct exec_package *pack;
85 	struct ps_strings *arginfo;
86 	char **stackp;
87 	void *argp;
88 {
89 	size_t len;
90 	AuxInfo ai[LINUX_ELF_AUX_ENTRIES], *a;
91 	struct elf_args *ap;
92 #ifdef LINUX_SP_WRAP
93 	AuxInfo *prog_entry = NULL;
94 	char	linux_sp_wrap_code[LINUX_SP_WRAP];
95 	unsigned long*	cga;
96 #endif
97 	int error;
98 
99 #ifdef LINUX_SHIFT
100 	/*
101 	 * Seems that PowerPC Linux binaries expect argc to start on a 16 bytes
102 	 * aligned address. And we need one more 16 byte shift if it was already
103 	 * 16 bytes aligned,
104 	 */
105 	*stackp = (char *)(((unsigned long)*stackp - 1) & ~LINUX_SHIFT);
106 #endif
107 
108 	if ((error = copyargs(p, pack, arginfo, stackp, argp)) != 0)
109 		return error;
110 
111 #ifdef LINUX_SHIFT
112 	/*
113 	 * From Linux's arch/ppc/kernel/process.c:shove_aux_table(). GNU ld.so
114 	 * expects the ELF auxiliary table to start on a 16 bytes boundary on
115 	 * the PowerPC.
116 	 */
117 	*stackp = (char *)(((unsigned long)(*stackp) + LINUX_SHIFT)
118 	    & ~LINUX_SHIFT);
119 #endif
120 
121 	memset(ai, 0, sizeof(AuxInfo) * LINUX_ELF_AUX_ENTRIES);
122 
123 	a = ai;
124 
125 	/*
126 	 * Push extra arguments on the stack needed by dynamically
127 	 * linked binaries.
128 	 */
129 	if ((ap = (struct elf_args *)pack->ep_emul_arg)) {
130 #ifdef LINUX_SP_WRAP
131 		memset(linux_sp_wrap_code, 0, LINUX_SP_WRAP);
132 		bcopy(&linux_sp_wrap_start, linux_sp_wrap_code,
133 		    (unsigned long)(&linux_sp_wrap_end)
134 		    - (unsigned long)(&linux_sp_wrap_start));
135 		(unsigned long)cga = ((unsigned long)linux_sp_wrap_code)
136 		    + ((unsigned long)(&linux_sp_wrap_entry))
137 		    - ((unsigned long)(&linux_sp_wrap_start));
138 		(*cga) = (unsigned long)(ap->arg_entry);
139 #endif
140 #if 1
141 		/*
142 		 * The exec_package doesn't have a proc pointer and it's not
143 		 * exactly trivial to add one since the credentials are
144 		 * changing. XXX Linux uses curlwp's credentials.
145 		 * Why can't we use them too?
146 		 */
147 		a->a_type = LINUX_AT_EGID;
148 		a->a_v = p->p_ucred->cr_gid;
149 		a++;
150 
151 		a->a_type = LINUX_AT_GID;
152 		a->a_v = p->p_cred->p_rgid;
153 		a++;
154 
155 		a->a_type = LINUX_AT_EUID;
156 		a->a_v = p->p_ucred->cr_uid;
157 		a++;
158 
159 		a->a_type = LINUX_AT_UID;
160 		a->a_v = p->p_cred->p_ruid;
161 		a++;
162 #endif
163 
164 		a->a_type = AT_ENTRY;
165 		a->a_v = ap->arg_entry;
166 #ifdef LINUX_SP_WRAP
167 		prog_entry = a;
168 #endif
169 		a++;
170 
171 		a->a_type = AT_FLAGS;
172 		a->a_v = 0;
173 		a++;
174 
175 		a->a_type = AT_BASE;
176 		a->a_v = ap->arg_interp;
177 		a++;
178 
179 		a->a_type = AT_PHNUM;
180 		a->a_v = ap->arg_phnum;
181 		a++;
182 
183 		a->a_type = AT_PHENT;
184 		a->a_v = ap->arg_phentsize;
185 		a++;
186 
187 		a->a_type = AT_PHDR;
188 		a->a_v = ap->arg_phaddr;
189 		a++;
190 
191 		a->a_type = LINUX_AT_CLKTCK;
192 		a->a_v = LINUX_CLOCKS_PER_SEC;
193 		a++;
194 
195 		a->a_type = AT_PAGESZ;
196 		a->a_v = PAGE_SIZE;
197 		a++;
198 
199 		a->a_type = LINUX_AT_HWCAP;
200 		a->a_v = LINUX_ELF_HWCAP;
201 		a++;
202 
203 		free((char *)ap, M_TEMP);
204 		pack->ep_emul_arg = NULL;
205 	}
206 
207 	a->a_type = AT_NULL;
208 	a->a_v = 0;
209 	a++;
210 
211 	len = (a - ai) * sizeof(AuxInfo);
212 
213 #ifdef LINUX_SP_WRAP
214 	if (prog_entry != NULL)
215 		prog_entry->a_v = (unsigned long)(*stackp) + len;
216 #endif
217 
218 	if ((error = copyout(ai, *stackp, len)) != 0)
219 		return error;
220 	*stackp += len;
221 
222 #ifdef LINUX_SP_WRAP
223 	if (prog_entry != NULL) {
224 		if ((error = copyout(linux_sp_wrap_code, *stackp,
225 		    LINUX_SP_WRAP)) != 0)
226 			return error;
227 		*stackp += LINUX_SP_WRAP;
228 	}
229 #endif
230 
231 	return 0;
232 }
233