exec_aout.c revision 1.7
1 /* 2 * Copyright (c) 1993 Christopher G. Demetriou 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by Christopher G. Demetriou. 16 * 4. The name of the author may not be used to endorse or promote products 17 * derived from this software withough specific prior written permission 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * $Id: exec_aout.c,v 1.7 1994/01/13 02:33:28 cgd Exp $ 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/proc.h> 36 #include <sys/malloc.h> 37 #include <sys/vnode.h> 38 #include <sys/exec.h> 39 #include <sys/resourcevar.h> 40 #include <vm/vm.h> 41 42 #include <sys/exec_aout.h> 43 #include <machine/exec.h> 44 45 /* 46 * exec_aout_makecmds(): Check if it's an a.out-format executable. 47 * 48 * Given a proc pointer and an exec package pointer, see if the referent 49 * of the epp is in a.out format. First check 'standard' magic numbers for 50 * this architecture. If that fails, try a cpu-dependent hook. 51 * 52 * This function, in the former case, or the hook, in the latter, is 53 * responsible for creating a set of vmcmds which can be used to build 54 * the process's vm space and inserting them into the exec package. 55 */ 56 57 int 58 exec_aout_makecmds(p, epp) 59 struct proc *p; 60 struct exec_package *epp; 61 { 62 u_long midmag, magic; 63 u_short mid; 64 int error; 65 66 midmag = ntohl(epp->ep_execp->a_midmag); 67 mid = (midmag >> 16) & 0x3ff; 68 magic = midmag & 0xffff; 69 70 midmag = mid << 16 | magic; 71 72 switch (midmag) { 73 case (MID_MACHINE << 16) | ZMAGIC: 74 error = exec_aout_prep_zmagic(p, epp); 75 break; 76 case (MID_MACHINE << 16) | NMAGIC: 77 error = exec_aout_prep_nmagic(p, epp); 78 break; 79 case (MID_MACHINE << 16) | OMAGIC: 80 error = exec_aout_prep_omagic(p, epp); 81 break; 82 default: 83 error = cpu_exec_aout_makecmds(p, epp); 84 } 85 86 if (error) 87 kill_vmcmds(&epp->ep_vmcmds); 88 89 bad: 90 return error; 91 } 92 93 /* 94 * exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's exec package 95 * 96 * First, set of the various offsets/lengths in the exec package. 97 * 98 * Then, mark the text image busy (so it can be demand paged) or error 99 * out if this is not possible. Finally, set up vmcmds for the 100 * text, data, bss, and stack segments. 101 */ 102 103 int 104 exec_aout_prep_zmagic(p, epp) 105 struct proc *p; 106 struct exec_package *epp; 107 { 108 struct exec *execp = epp->ep_execp; 109 110 epp->ep_taddr = USRTEXT; 111 epp->ep_tsize = execp->a_text; 112 epp->ep_daddr = epp->ep_taddr + execp->a_text; 113 epp->ep_dsize = execp->a_data + execp->a_bss; 114 epp->ep_entry = execp->a_entry; 115 116 /* 117 * check if vnode is in open for writing, because we want to 118 * demand-page out of it. if it is, don't do it, for various 119 * reasons 120 */ 121 if ((execp->a_text != 0 || execp->a_data != 0) && 122 epp->ep_vp->v_writecount != 0) { 123 #ifdef DIAGNOSTIC 124 if (epp->ep_vp->v_flag & VTEXT) 125 panic("exec: a VTEXT vnode has writecount != 0\n"); 126 #endif 127 return ETXTBSY; 128 } 129 epp->ep_vp->v_flag |= VTEXT; 130 131 /* set up command for text segment */ 132 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text, 133 epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE); 134 135 /* set up command for data segment */ 136 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data, 137 epp->ep_daddr, epp->ep_vp, execp->a_text, 138 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 139 140 /* set up command for bss segment */ 141 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss, 142 epp->ep_daddr + execp->a_data, NULLVP, 0, 143 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 144 145 return exec_aout_setup_stack(p, epp); 146 } 147 148 /* 149 * exec_aout_prep_nmagic(): Prepare a 'native' NMAGIC binary's exec package 150 */ 151 152 int 153 exec_aout_prep_nmagic(p, epp) 154 struct proc *p; 155 struct exec_package *epp; 156 { 157 struct exec *execp = epp->ep_execp; 158 long bsize, baddr; 159 160 epp->ep_taddr = USRTEXT; 161 epp->ep_tsize = execp->a_text; 162 epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, __LDPGSZ); 163 epp->ep_dsize = execp->a_data + execp->a_bss; 164 epp->ep_entry = execp->a_entry; 165 166 /* set up command for text segment */ 167 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text, 168 epp->ep_taddr, epp->ep_vp, sizeof(struct exec), 169 VM_PROT_READ|VM_PROT_EXECUTE); 170 171 /* set up command for data segment */ 172 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data, 173 epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec), 174 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 175 176 /* set up command for bss segment */ 177 baddr = roundup(epp->ep_daddr + execp->a_data, NBPG); 178 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 179 if (bsize > 0) 180 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 181 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 182 183 return exec_aout_setup_stack(p, epp); 184 } 185 186 /* 187 * exec_aout_prep_omagic(): Prepare a 'native' OMAGIC binary's exec package 188 */ 189 190 int 191 exec_aout_prep_omagic(p, epp) 192 struct proc *p; 193 struct exec_package *epp; 194 { 195 struct exec *execp = epp->ep_execp; 196 long bsize, baddr; 197 198 epp->ep_taddr = USRTEXT; 199 epp->ep_tsize = execp->a_text; 200 epp->ep_daddr = epp->ep_taddr + execp->a_text; 201 epp->ep_dsize = execp->a_data + execp->a_bss; 202 epp->ep_entry = execp->a_entry; 203 204 /* set up command for text and data segments */ 205 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, 206 execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp, 207 sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 208 209 /* set up command for bss segment */ 210 baddr = roundup(epp->ep_daddr + execp->a_data, NBPG); 211 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 212 if (bsize > 0) 213 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 214 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 215 216 return exec_aout_setup_stack(p, epp); 217 } 218 219 /* 220 * exec_aout_setup_stack(): Set up the stack segment for an a.out 221 * executable. 222 * 223 * Note that the ep_ssize parameter must be set to be the current stack 224 * limit; this is adjusted in the body of execve() to yield the 225 * appropriate stack segment usage once the argument length is 226 * calculated. 227 * 228 * This function returns an int for uniformity with other (future) formats' 229 * stack setup functions. They might have errors to return. 230 */ 231 232 int 233 exec_aout_setup_stack(p, epp) 234 struct proc *p; 235 struct exec_package *epp; 236 { 237 238 epp->ep_maxsaddr = USRSTACK - MAXSSIZ; 239 epp->ep_minsaddr = USRSTACK; 240 epp->ep_ssize = p->p_rlimit[RLIMIT_STACK].rlim_cur; 241 242 /* 243 * set up commands for stack. note that this takes *two*, one to 244 * map the part of the stack which we can access, and one to map 245 * the part which we can't. 246 * 247 * arguably, it could be made into one, but that would require the 248 * addition of another mapping proc, which is unnecessary 249 * 250 * note that in memory, things assumed to be: 0 ....... ep_maxsaddr 251 * <stack> ep_minsaddr 252 */ 253 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, 254 ((epp->ep_minsaddr - epp->ep_ssize) - epp->ep_maxsaddr), 255 epp->ep_maxsaddr, NULLVP, 0, VM_PROT_NONE); 256 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, epp->ep_ssize, 257 (epp->ep_minsaddr - epp->ep_ssize), NULLVP, 0, 258 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 259 260 return 0; 261 } 262
Indexes created Tue Sep 30 20:09:53 GMT 2025