xref: /netbsd/sys/compat/m68k4k/m68k4k_exec.c (revision 6550d01e)
1 /*	$NetBSD: m68k4k_exec.c,v 1.22 2009/08/17 06:00:05 cegger Exp $	*/
2 
3 /*
4  * Copyright (c) 1993, 1994 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by Christopher G. Demetriou.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * Exec glue to provide compatibility with older NetBSD m68k4k exectuables.
35  *
36  * Taken directly from kern/exec_aout.c and frobbed to map text and
37  * data as m68k4k executables expect.
38  *
39  * This module only works on machines with PAGE_SIZE == 4096.  It's not clear
40  * that making it work on other machines is worth the trouble.
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: m68k4k_exec.c,v 1.22 2009/08/17 06:00:05 cegger Exp $");
45 
46 #if !defined(__m68k__)
47 #error YOU GOTTA BE KIDDING!
48 #endif
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/proc.h>
53 #include <sys/malloc.h>
54 #include <sys/module.h>
55 #include <sys/vnode.h>
56 #include <sys/exec.h>
57 #include <sys/exec_aout.h>
58 #include <sys/resourcevar.h>
59 
60 #include <compat/m68k4k/m68k4k_exec.h>
61 
62 #ifdef COREDUMP
63 #define	DEP	"coredump"
64 #else
65 #define	DEP	NULL
66 #endif
67 
68 MODULE(MODULE_CLASS_MISC, exec_m68k4k, DEP);
69 
70 static struct execsw exec_m68k4k_execsw[] = {
71 	{ sizeof(struct exec),
72 	  exec_m68k4k_makecmds,
73 	  { NULL },
74 	  &emul_netbsd,
75 	  EXECSW_PRIO_ANY,
76 	  0,
77 	  copyargs,
78 	  NULL,
79 	  coredump_netbsd,
80 	  exec_setup_stack },
81 };
82 
83 static int
84 exec_m68k4k_modcmd(modcmd_t cmd, void *arg)
85 {
86 
87 	switch (cmd) {
88 	case MODULE_CMD_INIT:
89 		return exec_add(exec_m68k4k_execsw,
90 		    __arraycount(exec_m68k4k_execsw));
91 
92 	case MODULE_CMD_FINI:
93 		return exec_remove(exec_m68k4k_execsw,
94 		    __arraycount(exec_m68k4k_execsw));
95 
96 	default:
97 		return ENOTTY;
98         }
99 }
100 
101 int	exec_m68k4k_prep_zmagic(struct lwp *, struct exec_package *);
102 int	exec_m68k4k_prep_nmagic(struct lwp *, struct exec_package *);
103 int	exec_m68k4k_prep_omagic(struct lwp *, struct exec_package *);
104 
105 /*
106  * exec_m68k4k_makecmds(): Check if it's an a.out-format executable
107  * with an m68k4k magic number.
108  *
109  * Given a proc pointer and an exec package pointer, see if the referent
110  * of the epp is in a.out format.  Just check 'standard' magic numbers for
111  * this architecture.
112  *
113  * This function, in the former case, or the hook, in the latter, is
114  * responsible for creating a set of vmcmds which can be used to build
115  * the process's vm space and inserting them into the exec package.
116  */
117 
118 int
119 exec_m68k4k_makecmds(struct lwp *l, struct exec_package *epp)
120 {
121 	u_long midmag, magic;
122 	u_short mid;
123 	int error;
124 	struct exec *execp = epp->ep_hdr;
125 
126 	/* See note above... */
127 	if (M68K4K_LDPGSZ != PAGE_SIZE)
128 		return ENOEXEC;
129 
130 	if (epp->ep_hdrvalid < sizeof(struct exec))
131 		return ENOEXEC;
132 
133 	midmag = ntohl(execp->a_midmag);
134 	mid = (midmag >> 16) & 0x3ff;
135 	magic = midmag & 0xffff;
136 
137 	midmag = mid << 16 | magic;
138 
139 	switch (midmag) {
140 	case (MID_M68K4K << 16) | ZMAGIC:
141 		error = exec_m68k4k_prep_zmagic(l, epp);
142 		break;
143 	case (MID_M68K4K << 16) | NMAGIC:
144 		error = exec_m68k4k_prep_nmagic(l, epp);
145 		break;
146 	case (MID_M68K4K << 16) | OMAGIC:
147 		error = exec_m68k4k_prep_omagic(l, epp);
148 		break;
149 	default:
150 		error = ENOEXEC;
151 	}
152 
153 	if (error)
154 		kill_vmcmds(&epp->ep_vmcmds);
155 
156 	return error;
157 }
158 
159 /*
160  * exec_m68k4k_prep_zmagic(): Prepare an m68k4k ZMAGIC binary's exec package
161  *
162  * First, set of the various offsets/lengths in the exec package.
163  *
164  * Then, mark the text image busy (so it can be demand paged) or error
165  * out if this is not possible.  Finally, set up vmcmds for the
166  * text, data, bss, and stack segments.
167  */
168 
169 int
170 exec_m68k4k_prep_zmagic(struct lwp *l, struct exec_package *epp)
171 {
172 	struct exec *execp = epp->ep_hdr;
173 	int error;
174 
175 	epp->ep_taddr = M68K4K_USRTEXT;
176 	epp->ep_tsize = execp->a_text;
177 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
178 	epp->ep_dsize = execp->a_data + execp->a_bss;
179 	epp->ep_entry = execp->a_entry;
180 
181 	error = vn_marktext(epp->ep_vp);
182 	if (error)
183 		return (error);
184 
185 	/* set up command for text segment */
186 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
187 	    epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE);
188 
189 	/* set up command for data segment */
190 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
191 	    epp->ep_daddr, epp->ep_vp, execp->a_text,
192 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
193 
194 	/* set up command for bss segment */
195 	if (execp->a_bss)
196 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
197 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
198 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
199 
200 	return (*epp->ep_esch->es_setup_stack)(l, epp);
201 }
202 
203 /*
204  * exec_m68k4k_prep_nmagic(): Prepare a m68k4k NMAGIC binary's exec package
205  */
206 
207 int
208 exec_m68k4k_prep_nmagic(struct lwp *l, struct exec_package *epp)
209 {
210 	struct exec *execp = epp->ep_hdr;
211 	long bsize, baddr;
212 
213 	epp->ep_taddr = M68K4K_USRTEXT;
214 	epp->ep_tsize = execp->a_text;
215 	epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text,
216 	    M68K4K_LDPGSZ);
217 	epp->ep_dsize = execp->a_data + execp->a_bss;
218 	epp->ep_entry = execp->a_entry;
219 
220 	/* set up command for text segment */
221 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
222 	    epp->ep_taddr, epp->ep_vp, sizeof(struct exec),
223 	    VM_PROT_READ|VM_PROT_EXECUTE);
224 
225 	/* set up command for data segment */
226 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
227 	    epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec),
228 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
229 
230 	/* set up command for bss segment */
231 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
232 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
233 	if (bsize > 0)
234 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
235 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
236 
237 	return (*epp->ep_esch->es_setup_stack)(l, epp);
238 }
239 
240 /*
241  * exec_m68k4k_prep_omagic(): Prepare a m68k4k OMAGIC binary's exec package
242  */
243 
244 int
245 exec_m68k4k_prep_omagic(struct lwp *l, struct exec_package *epp)
246 {
247 	struct exec *execp = epp->ep_hdr;
248 	long dsize, bsize, baddr;
249 
250 	epp->ep_taddr = M68K4K_USRTEXT;
251 	epp->ep_tsize = execp->a_text;
252 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
253 	epp->ep_dsize = execp->a_data + execp->a_bss;
254 	epp->ep_entry = execp->a_entry;
255 
256 	/* set up command for text and data segments */
257 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
258 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
259 	    sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
260 
261 	/* set up command for bss segment */
262 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
263 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
264 	if (bsize > 0)
265 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
266 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
267 
268 	/*
269 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
270 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
271 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
272 	 * respectively to page boundaries.
273 	 * Compensate `ep_dsize' for the amount of data covered by the last
274 	 * text page.
275 	 */
276 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
277 							PAGE_SIZE);
278 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
279 	return (*epp->ep_esch->es_setup_stack)(l, epp);
280 }
281