xref: /netbsd-src/sys/kern/exec_ecoff.c (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: exec_ecoff.c,v 1.12 2000/06/27 17:41:08 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 1994 Adam Glass
5  * Copyright (c) 1993, 1994, 1996, 1999 Christopher G. Demetriou
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *      This product includes software developed by Christopher G. Demetriou
19  *      for the NetBSD Project.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/proc.h>
38 #include <sys/malloc.h>
39 #include <sys/vnode.h>
40 #include <sys/exec.h>
41 #include <sys/resourcevar.h>
42 
43 #include <sys/exec_ecoff.h>
44 
45 /*
46  * exec_ecoff_makecmds(): Check if it's an ecoff-format executable.
47  *
48  * Given a proc pointer and an exec package pointer, see if the referent
49  * of the epp is in ecoff format.  Check 'standard' magic numbers for
50  * this architecture.  If that fails, return failure.
51  *
52  * This function is  responsible for creating a set of vmcmds which can be
53  * used to build the process's vm space and inserting them into the exec
54  * package.
55  */
56 int
57 exec_ecoff_makecmds(p, epp)
58 	struct proc *p;
59 	struct exec_package *epp;
60 {
61 	int error;
62 	struct ecoff_exechdr *execp = epp->ep_hdr;
63 
64 	if (epp->ep_hdrvalid < ECOFF_HDR_SIZE)
65 		return ENOEXEC;
66 
67 	if (ECOFF_BADMAG(execp))
68 		return ENOEXEC;
69 
70 	error = cpu_exec_ecoff_hook(p, epp);
71 
72 	/*
73 	 * if there was an error or there are already vmcmds set up,
74 	 * we return.  (the latter can happen if cpu_exec_ecoff_hook()
75 	 * recursively invokes check_exec() to handle loading of a
76 	 * dynamically linked binary's shared loader.
77 	 */
78 	if (error || epp->ep_vmcmds.evs_cnt)
79 		return (error);
80 
81 	/*
82 	 * prepare the exec package to map the executable.
83 	 */
84 	switch (execp->a.magic) {
85 	case ECOFF_OMAGIC:
86 		error = exec_ecoff_prep_omagic(p, epp, epp->ep_hdr,
87 		   epp->ep_vp);
88 		break;
89 	case ECOFF_NMAGIC:
90 		error = exec_ecoff_prep_nmagic(p, epp, epp->ep_hdr,
91 		   epp->ep_vp);
92 		break;
93 	case ECOFF_ZMAGIC:
94 		error = exec_ecoff_prep_zmagic(p, epp, epp->ep_hdr,
95 		   epp->ep_vp);
96 		break;
97 	default:
98 		return ENOEXEC;
99 	}
100 
101 	/* set up the stack */
102 	if (!error)
103 		error = exec_ecoff_setup_stack(p, epp);
104 
105 	if (error)
106 		kill_vmcmds(&epp->ep_vmcmds);
107 
108 	return error;
109 }
110 
111 /*
112  * exec_ecoff_setup_stack(): Set up the stack segment for an ecoff
113  * executable.
114  *
115  * Note that the ep_ssize parameter must be set to be the current stack
116  * limit; this is adjusted in the body of execve() to yield the
117  * appropriate stack segment usage once the argument length is
118  * calculated.
119  *
120  * This function returns an int for uniformity with other (future) formats'
121  * stack setup functions.  They might have errors to return.
122  */
123 int
124 exec_ecoff_setup_stack(p, epp)
125 	struct proc *p;
126 	struct exec_package *epp;
127 {
128 
129 	epp->ep_maxsaddr = USRSTACK - MAXSSIZ;
130 	epp->ep_minsaddr = USRSTACK;
131 	epp->ep_ssize = p->p_rlimit[RLIMIT_STACK].rlim_cur;
132 
133 	/*
134 	 * set up commands for stack.  note that this takes *two*, one to
135 	 * map the part of the stack which we can access, and one to map
136 	 * the part which we can't.
137 	 *
138 	 * arguably, it could be made into one, but that would require the
139 	 * addition of another mapping proc, which is unnecessary
140 	 *
141 	 * note that in memory, things assumed to be: 0 ... ep_maxsaddr
142 	 * <stack> ep_minsaddr
143 	 */
144 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero,
145 	    ((epp->ep_minsaddr - epp->ep_ssize) - epp->ep_maxsaddr),
146 	    epp->ep_maxsaddr, NULLVP, 0, VM_PROT_NONE);
147 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, epp->ep_ssize,
148 	    (epp->ep_minsaddr - epp->ep_ssize), NULLVP, 0,
149 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
150 
151 	return 0;
152 }
153 
154 /*
155  * exec_ecoff_prep_omagic(): Prepare a ECOFF OMAGIC binary's exec package
156  */
157 int
158 exec_ecoff_prep_omagic(p, epp, execp, vp)
159 	struct proc *p;
160 	struct exec_package *epp;
161 	struct ecoff_exechdr *execp;
162 	struct vnode *vp;
163 {
164 	struct ecoff_aouthdr *eap = &execp->a;
165 
166 	epp->ep_taddr = ECOFF_SEGMENT_ALIGN(execp, eap->text_start);
167 	epp->ep_tsize = eap->tsize;
168 	epp->ep_daddr = ECOFF_SEGMENT_ALIGN(execp, eap->data_start);
169 	epp->ep_dsize = eap->dsize + eap->bsize;
170 	epp->ep_entry = eap->entry;
171 
172 	/* set up command for text and data segments */
173 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
174 	    eap->tsize + eap->dsize, epp->ep_taddr, vp,
175 	    ECOFF_TXTOFF(execp),
176 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
177 
178 	/* set up command for bss segment */
179 	if (eap->bsize > 0)
180 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, eap->bsize,
181 		    ECOFF_SEGMENT_ALIGN(execp, eap->bss_start), NULLVP, 0,
182 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
183 
184 	return 0;
185 }
186 
187 /*
188  * exec_ecoff_prep_nmagic(): Prepare a 'native' NMAGIC ECOFF binary's exec
189  *                           package.
190  */
191 int
192 exec_ecoff_prep_nmagic(p, epp, execp, vp)
193 	struct proc *p;
194 	struct exec_package *epp;
195 	struct ecoff_exechdr *execp;
196 	struct vnode *vp;
197 {
198 	struct ecoff_aouthdr *eap = &execp->a;
199 
200 	epp->ep_taddr = ECOFF_SEGMENT_ALIGN(execp, eap->text_start);
201 	epp->ep_tsize = eap->tsize;
202 	epp->ep_daddr = ECOFF_ROUND(eap->data_start, ECOFF_LDPGSZ);
203 	epp->ep_dsize = eap->dsize + eap->bsize;
204 	epp->ep_entry = eap->entry;
205 
206 	/* set up command for text segment */
207 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, epp->ep_tsize,
208 	    epp->ep_taddr, vp, ECOFF_TXTOFF(execp),
209 	    VM_PROT_READ|VM_PROT_EXECUTE);
210 
211 	/* set up command for data segment */
212 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, epp->ep_dsize,
213 	    epp->ep_daddr, vp, ECOFF_DATOFF(execp),
214 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
215 
216 	/* set up command for bss segment */
217 	if (eap->bsize > 0)
218 		NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, eap->bsize,
219 		    ECOFF_SEGMENT_ALIGN(execp, eap->bss_start), NULLVP, 0,
220 		    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
221 
222 	return 0;
223 }
224 
225 /*
226  * exec_ecoff_prep_zmagic(): Prepare a ECOFF ZMAGIC binary's exec package
227  *
228  * First, set the various offsets/lengths in the exec package.
229  *
230  * Then, mark the text image busy (so it can be demand paged) or error
231  * out if this is not possible.  Finally, set up vmcmds for the
232  * text, data, bss, and stack segments.
233  */
234 int
235 exec_ecoff_prep_zmagic(p, epp, execp, vp)
236 	struct proc *p;
237 	struct exec_package *epp;
238 	struct ecoff_exechdr *execp;
239 	struct vnode *vp;
240 {
241 	struct ecoff_aouthdr *eap = &execp->a;
242 
243 	epp->ep_taddr = ECOFF_SEGMENT_ALIGN(execp, eap->text_start);
244 	epp->ep_tsize = eap->tsize;
245 	epp->ep_daddr = ECOFF_SEGMENT_ALIGN(execp, eap->data_start);
246 	epp->ep_dsize = eap->dsize + eap->bsize;
247 	epp->ep_entry = eap->entry;
248 
249 	/*
250 	 * check if vnode is in open for writing, because we want to
251 	 * demand-page out of it.  if it is, don't do it, for various
252 	 * reasons
253 	 */
254 	if ((eap->tsize != 0 || eap->dsize != 0) &&
255 	    vp->v_writecount != 0) {
256 #ifdef DIAGNOSTIC
257 		if (vp->v_flag & VTEXT)
258 			panic("exec: a VTEXT vnode has writecount != 0\n");
259 #endif
260 		return ETXTBSY;
261 	}
262 	vn_marktext(vp);
263 
264 	/* set up command for text segment */
265 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, eap->tsize,
266 	    epp->ep_taddr, vp, ECOFF_TXTOFF(execp),
267 	    VM_PROT_READ|VM_PROT_EXECUTE);
268 
269 	/* set up command for data segment */
270 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, eap->dsize,
271 	    epp->ep_daddr, vp, ECOFF_DATOFF(execp),
272 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
273 
274 	/* set up command for bss segment */
275 	NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, eap->bsize,
276 	    ECOFF_SEGMENT_ALIGN(execp, eap->bss_start), NULLVP, 0,
277 	    VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
278 
279 	return 0;
280 }
281