sys/compat/vax1k/vax1k_exec.c

   1 /*      $NetBSD: vax1k_exec.c,v 1.15 2008/02/13 17:41:09 matt 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 vax1k exectuables.
  35  *
  36  * Because NetBSD/vax now uses 4k page size, older binaries (that started
  37  * on an 1k boundary) cannot be mmap'ed. Therefore they are read in
  38  * (via vn_rdwr) as OMAGIC binaries and executed. This will use a little
  39  * bit more memory, but otherwise won't affect the execution speed.
  40  */
  41
  42 #include <sys/cdefs.h>
  43 __KERNEL_RCSID(0, "$NetBSD: vax1k_exec.c,v 1.15 2008/02/13 17:41:09 matt Exp $");
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #include <sys/proc.h>
  48 #include <sys/malloc.h>
  49 #include <sys/vnode.h>
  50 #include <sys/exec.h>
  51 #include <sys/resourcevar.h>
  52 #include <sys/module.h>
  53
  54 #include <compat/vax1k/vax1k_exec.h>
  55
  56 #if defined(_KERNEL_OPT)
  57 #include "opt_compat_43.h"
  58 #include "opt_coredump.h"
  59 #else
  60 #define COMPAT_43       /* enable 4.3BSD binaries for lkm */
  61 #endif
  62
  63 #ifdef COREDUMP
  64 MODULE(MODULE_CLASS_MISC, exec_vax1k, "coredump");
  65 #else
  66 MODULE(MODULE_CLASS_MISC, exec_vax1k, NULL);
  67 #endif
  68
  69 int     exec_vax1k_prep_anymagic(struct lwp *, struct exec_package *,
  70             size_t, bool);
  71
  72 static struct execsw exec_vax1k_execsw[] = {
  73         /* NetBSD vax1k a.out */
  74         { sizeof(struct exec),
  75           exec_vax1k_makecmds,
  76           { NULL },
  77           &emul_netbsd,
  78           EXECSW_PRIO_ANY,
  79           0,
  80           copyargs,
  81           NULL,
  82           coredump_netbsd,
  83           exec_setup_stack },
  84 };
  85
  86 static int
  87 exec_vax1k_modcmd(modcmd_t cmd, void *arg)
  88 {
  89
  90         switch (cmd) {
  91         case MODULE_CMD_INIT:
  92                 return exec_add(exec_vax1k_execsw,
  93                     __arraycount(exec_vax1k_execsw));
  94
  95         case MODULE_CMD_FINI:
  96                 return exec_remove(exec_vax1k_execsw,
  97                     __arraycount(exec_vax1k_execsw));
  98
  99         default:
 100                 return ENOTTY;
 101         }
 102 }
 103
 104 /*
 105  * exec_vax1k_makecmds(): Check if it's an a.out-format executable
 106  * with an vax1k 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_vax1k_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         if (epp->ep_hdrvalid < sizeof(struct exec))
 126                 return ENOEXEC;
 127
 128         midmag = ntohl(execp->a_midmag);
 129         mid = (midmag >> 16) & 0x3ff;
 130         magic = midmag & 0xffff;
 131
 132         midmag = mid << 16 | magic;
 133
 134         switch (midmag) {
 135         case (MID_VAX1K << 16) | ZMAGIC:
 136                 error = exec_vax1k_prep_anymagic(l, epp, 0, false);
 137                 goto done;
 138
 139         case (MID_VAX1K << 16) | NMAGIC:
 140                 error = exec_vax1k_prep_anymagic(l, epp,
 141                                                  sizeof(struct exec), true);
 142                 goto done;
 143
 144         case (MID_VAX1K << 16) | OMAGIC:
 145                 error = exec_vax1k_prep_anymagic(l, epp,
 146                                                  sizeof(struct exec), false);
 147                 goto done;
 148         }
 149
 150 #ifdef COMPAT_43
 151         /*
 152          * 4.3BSD pre-dates CPU midmag (e.g. MID_VAX1K).   instead, we
 153          * expect a magic number in native byte order.
 154          */
 155         switch (execp->a_midmag) {
 156         case ZMAGIC:
 157                 error = exec_vax1k_prep_anymagic(l, epp, VAX1K_LDPGSZ, false);
 158                 goto done;
 159
 160         case NMAGIC:
 161                 error = exec_vax1k_prep_anymagic(l, epp,
 162                                                 sizeof(struct exec), true);
 163                 goto done;
 164
 165         case OMAGIC:
 166                 error = exec_vax1k_prep_anymagic(l, epp,
 167                                                 sizeof(struct exec), false);
 168                 goto done;
 169         }
 170 #endif
 171
 172         /* failed... */
 173         error = ENOEXEC;
 174
 175 done:
 176         if (error)
 177                 kill_vmcmds(&epp->ep_vmcmds);
 178
 179         return error;
 180 }
 181
 182 /*
 183  * exec_vax1k_prep_anymagic(): Prepare an vax1k ?MAGIC binary's exec package
 184  *
 185  * First, set of the various offsets/lengths in the exec package.
 186  * Note that all code is mapped RW; no protection, but because it is
 187  * only used for compatibility it won't hurt.
 188  *
 189  */
 190 int
 191 exec_vax1k_prep_anymagic(struct lwp *l, struct exec_package *epp,
 192         size_t text_foffset, bool textpad)
 193 {
 194         struct exec *execp = epp->ep_hdr;
 195
 196         epp->ep_taddr = execp->a_entry & ~(VAX1K_USRTEXT - 1);
 197         epp->ep_tsize = execp->a_text;
 198         epp->ep_daddr = epp->ep_taddr + epp->ep_tsize;
 199         if (textpad)                    /* pad for NMAGIC? */
 200                 epp->ep_daddr = (epp->ep_daddr + (VAX1K_LDPGSZ - 1)) &
 201                                                 ~(VAX1K_LDPGSZ - 1);
 202         epp->ep_dsize = execp->a_data;
 203         epp->ep_entry = execp->a_entry;
 204
 205         /* first allocate memory for text+data+bss */
 206         NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero,
 207                 round_page(epp->ep_daddr + epp->ep_dsize + execp->a_bss) -
 208                         trunc_page(epp->ep_taddr),      /* size */
 209                 trunc_page(epp->ep_taddr), NULLVP,      /* addr, vnode */
 210                 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
 211
 212         /* then read the text in the area we just allocated */
 213         NEW_VMCMD(&epp->ep_vmcmds, vmcmd_readvn,
 214                 epp->ep_tsize, epp->ep_taddr, epp->ep_vp, text_foffset,
 215         VM_PROT_WRITE|VM_PROT_READ|VM_PROT_EXECUTE);
 216
 217         /* next read the data */
 218         if (epp->ep_dsize) {
 219                 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_readvn,
 220                         epp->ep_dsize, epp->ep_daddr, epp->ep_vp,
 221                         text_foffset + epp->ep_tsize,
 222                         VM_PROT_WRITE|VM_PROT_READ|VM_PROT_EXECUTE);
 223         }
 224
 225         /* now bump up the dsize to include the bss so that sbrk works */
 226         epp->ep_dsize += execp->a_bss;
 227
 228         /* finally, setup the stack ... */
 229         return (*epp->ep_esch->es_setup_stack)(l, epp);
 230 }