xref: /netbsd-src/sys/compat/m68k4k/m68k4k_exec.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /*	$NetBSD: m68k4k_exec.c,v 1.21 2008/11/21 19:55:38 he 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 1.21 2008/11/21 19:55:38 he 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/resourcevar.h>
58 
59 #include <compat/m68k4k/m68k4k_exec.h>
60 
61 #ifdef COREDUMP
62 #define	DEP	"coredump"
63 #else
64 #define	DEP	NULL
65 #endif
66 
67 MODULE(MODULE_CLASS_MISC, exec_m68k4k, DEP);
68 
69 static struct execsw exec_m68k4k_execsw[] = {
70 	{ sizeof(struct exec),
71 	  exec_m68k4k_makecmds,
72 	  { NULL },
73 	  &emul_netbsd,
74 	  EXECSW_PRIO_ANY,
75 	  0,
76 	  copyargs,
77 	  NULL,
78 	  coredump_netbsd,
79 	  exec_setup_stack },
80 };
81 
82 static int
83 exec_m68k4k_modcmd(modcmd_t cmd, void *arg)
84 {
85 
86 	switch (cmd) {
87 	case MODULE_CMD_INIT:
88 		return exec_add(exec_m68k4k_execsw,
89 		    __arraycount(exec_m68k4k_execsw));
90 
91 	case MODULE_CMD_FINI:
92 		return exec_remove(exec_m68k4k_execsw,
93 		    __arraycount(exec_m68k4k_execsw));
94 
95 	default:
96 		return ENOTTY;
97         }
98 }
99 
100 int	exec_m68k4k_prep_zmagic(struct lwp *, struct exec_package *);
101 int	exec_m68k4k_prep_nmagic(struct lwp *, struct exec_package *);
102 int	exec_m68k4k_prep_omagic(struct lwp *, struct exec_package *);
103 
104 /*
105  * exec_m68k4k_makecmds(): Check if it's an a.out-format executable
106  * with an m68k4k magic number.
107  *
108  * Given a proc pointer and an exec package pointer, see if the referent
109  * of the epp is in a.out format.  Just check 'standard' magic numbers for
110  * this architecture.
111  *
112  * This function, in the former case, or the hook, in the latter, is
113  * responsible for creating a set of vmcmds which can be used to build
114  * the process's vm space and inserting them into the exec package.
115  */
116 
117 int
118 exec_m68k4k_makecmds(struct lwp *l, struct exec_package *epp)
119 {
120 	u_long midmag, magic;
121 	u_short mid;
122 	int error;
123 	struct exec *execp = epp->ep_hdr;
124 
125 	/* See note above... */
126 	if (M68K4K_LDPGSZ != PAGE_SIZE)
127 		return ENOEXEC;
128 
129 	if (epp->ep_hdrvalid < sizeof(struct exec))
130 		return ENOEXEC;
131 
132 	midmag = ntohl(execp->a_midmag);
133 	mid = (midmag >> 16) & 0x3ff;
134 	magic = midmag & 0xffff;
135 
136 	midmag = mid << 16 | magic;
137 
138 	switch (midmag) {
139 	case (MID_M68K4K << 16) | ZMAGIC:
140 		error = exec_m68k4k_prep_zmagic(l, epp);
141 		break;
142 	case (MID_M68K4K << 16) | NMAGIC:
143 		error = exec_m68k4k_prep_nmagic(l, epp);
144 		break;
145 	case (MID_M68K4K << 16) | OMAGIC:
146 		error = exec_m68k4k_prep_omagic(l, epp);
147 		break;
148 	default:
149 		error = ENOEXEC;
150 	}
151 
152 	if (error)
153 		kill_vmcmds(&epp->ep_vmcmds);
154 
155 	return error;
156 }
157 
158 /*
159  * exec_m68k4k_prep_zmagic(): Prepare an m68k4k ZMAGIC binary's exec package
160  *
161  * First, set of the various offsets/lengths in the exec package.
162  *
163  * Then, mark the text image busy (so it can be demand paged) or error
164  * out if this is not possible.  Finally, set up vmcmds for the
165  * text, data, bss, and stack segments.
166  */
167 
168 int
169 exec_m68k4k_prep_zmagic(struct lwp *l, struct exec_package *epp)
170 {
171 	struct exec *execp = epp->ep_hdr;
172 	int error;
173 
174 	epp->ep_taddr = M68K4K_USRTEXT;
175 	epp->ep_tsize = execp->a_text;
176 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
177 	epp->ep_dsize = execp->a_data + execp->a_bss;
178 	epp->ep_entry = execp->a_entry;
179 
180 	error = vn_marktext(epp->ep_vp);
181 	if (error)
182 		return (error);
183 
184 	/* set up command for text segment */
185 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
186 	    epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE);
187 
188 	/* set up command for data segment */
189 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
190 	    epp->ep_daddr, epp->ep_vp, execp->a_text,
191 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
192 
193 	/* set up command for bss segment */
194 	if (execp->a_bss)
195 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
196 		    epp->ep_daddr + execp->a_data, NULLVP, 0,
197 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
198 
199 	return (*epp->ep_esch->es_setup_stack)(l, epp);
200 }
201 
202 /*
203  * exec_m68k4k_prep_nmagic(): Prepare a m68k4k NMAGIC binary's exec package
204  */
205 
206 int
207 exec_m68k4k_prep_nmagic(struct lwp *l, struct exec_package *epp)
208 {
209 	struct exec *execp = epp->ep_hdr;
210 	long bsize, baddr;
211 
212 	epp->ep_taddr = M68K4K_USRTEXT;
213 	epp->ep_tsize = execp->a_text;
214 	epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text,
215 	    M68K4K_LDPGSZ);
216 	epp->ep_dsize = execp->a_data + execp->a_bss;
217 	epp->ep_entry = execp->a_entry;
218 
219 	/* set up command for text segment */
220 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
221 	    epp->ep_taddr, epp->ep_vp, sizeof(struct exec),
222 	    VM_PROT_READ|VM_PROT_EXECUTE);
223 
224 	/* set up command for data segment */
225 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
226 	    epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec),
227 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
228 
229 	/* set up command for bss segment */
230 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
231 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
232 	if (bsize > 0)
233 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
234 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
235 
236 	return (*epp->ep_esch->es_setup_stack)(l, epp);
237 }
238 
239 /*
240  * exec_m68k4k_prep_omagic(): Prepare a m68k4k OMAGIC binary's exec package
241  */
242 
243 int
244 exec_m68k4k_prep_omagic(struct lwp *l, struct exec_package *epp)
245 {
246 	struct exec *execp = epp->ep_hdr;
247 	long dsize, bsize, baddr;
248 
249 	epp->ep_taddr = M68K4K_USRTEXT;
250 	epp->ep_tsize = execp->a_text;
251 	epp->ep_daddr = epp->ep_taddr + execp->a_text;
252 	epp->ep_dsize = execp->a_data + execp->a_bss;
253 	epp->ep_entry = execp->a_entry;
254 
255 	/* set up command for text and data segments */
256 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
257 	    execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
258 	    sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
259 
260 	/* set up command for bss segment */
261 	baddr = roundup(epp->ep_daddr + execp->a_data, PAGE_SIZE);
262 	bsize = epp->ep_daddr + epp->ep_dsize - baddr;
263 	if (bsize > 0)
264 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
265 		    NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
266 
267 	/*
268 	 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
269 	 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
270 	 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
271 	 * respectively to page boundaries.
272 	 * Compensate `ep_dsize' for the amount of data covered by the last
273 	 * text page.
274 	 */
275 	dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text,
276 							PAGE_SIZE);
277 	epp->ep_dsize = (dsize > 0) ? dsize : 0;
278 	return (*epp->ep_esch->es_setup_stack)(l, epp);
279 }
280