sys/fs/procfs/procfs_map.c

   1 /*-
   2  * Copyright (c) 1993 Jan-Simon Pendry
   3  * Copyright (c) 1993
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * This code is derived from software contributed to Berkeley by
   7  * Jan-Simon Pendry.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)procfs_status.c     8.3 (Berkeley) 2/17/94
  34  *
  35  * $FreeBSD$
  36  */
  37
  38 #include "opt_compat.h"
  39
  40 #include <sys/param.h>
  41 #include <sys/systm.h>
  42 #include <sys/lock.h>
  43 #include <sys/filedesc.h>
  44 #include <sys/malloc.h>
  45 #include <sys/mount.h>
  46 #include <sys/proc.h>
  47 #include <sys/resourcevar.h>
  48 #include <sys/rwlock.h>
  49 #include <sys/sbuf.h>
  50 #ifdef COMPAT_FREEBSD32
  51 #include <sys/sysent.h>
  52 #endif
  53 #include <sys/uio.h>
  54 #include <sys/vnode.h>
  55
  56 #include <fs/pseudofs/pseudofs.h>
  57 #include <fs/procfs/procfs.h>
  58
  59 #include <vm/vm.h>
  60 #include <vm/vm_extern.h>
  61 #include <vm/pmap.h>
  62 #include <vm/vm_map.h>
  63 #include <vm/vm_page.h>
  64 #include <vm/vm_object.h>
  65
  66 #define MEBUFFERSIZE 256
  67
  68 /*
  69  * The map entries can *almost* be read with programs like cat.  However,
  70  * large maps need special programs to read.  It is not easy to implement
  71  * a program that can sense the required size of the buffer, and then
  72  * subsequently do a read with the appropriate size.  This operation cannot
  73  * be atomic.  The best that we can do is to allow the program to do a read
  74  * with an arbitrarily large buffer, and return as much as we can.  We can
  75  * return an error code if the buffer is too small (EFBIG), then the program
  76  * can try a bigger buffer.
  77  */
  78 int
  79 procfs_doprocmap(PFS_FILL_ARGS)
  80 {
  81         struct vmspace *vm;
  82         vm_map_t map;
  83         vm_map_entry_t entry, tmp_entry;
  84         struct vnode *vp;
  85         char *fullpath, *freepath;
  86         struct ucred *cred;
  87         int error;
  88         unsigned int last_timestamp;
  89 #ifdef COMPAT_FREEBSD32
  90         int wrap32 = 0;
  91 #endif
  92
  93         PROC_LOCK(p);
  94         error = p_candebug(td, p);
  95         PROC_UNLOCK(p);
  96         if (error)
  97                 return (error);
  98
  99         if (uio->uio_rw != UIO_READ)
 100                 return (EOPNOTSUPP);
 101
 102 #ifdef COMPAT_FREEBSD32
 103         if (SV_CURPROC_FLAG(SV_ILP32)) {
 104                 if (!(SV_PROC_FLAG(p, SV_ILP32)))
 105                         return (EOPNOTSUPP);
 106                 wrap32 = 1;
 107         }
 108 #endif
 109
 110         vm = vmspace_acquire_ref(p);
 111         if (vm == NULL)
 112                 return (ESRCH);
 113         map = &vm->vm_map;
 114         vm_map_lock_read(map);
 115         for (entry = map->header.next; entry != &map->header;
 116              entry = entry->next) {
 117                 vm_object_t obj, tobj, lobj;
 118                 int ref_count, shadow_count, flags;
 119                 vm_offset_t e_start, e_end, addr;
 120                 int resident, privateresident;
 121                 char *type;
 122                 vm_eflags_t e_eflags;
 123                 vm_prot_t e_prot;
 124
 125                 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP)
 126                         continue;
 127
 128                 e_eflags = entry->eflags;
 129                 e_prot = entry->protection;
 130                 e_start = entry->start;
 131                 e_end = entry->end;
 132                 privateresident = 0;
 133                 obj = entry->object.vm_object;
 134                 if (obj != NULL) {
 135                         VM_OBJECT_RLOCK(obj);
 136                         if (obj->shadow_count == 1)
 137                                 privateresident = obj->resident_page_count;
 138                 }
 139                 cred = (entry->cred) ? entry->cred : (obj ? obj->cred : NULL);
 140
 141                 resident = 0;
 142                 addr = entry->start;
 143                 while (addr < entry->end) {
 144                         if (pmap_extract(map->pmap, addr))
 145                                 resident++;
 146                         addr += PAGE_SIZE;
 147                 }
 148
 149                 for (lobj = tobj = obj; tobj; tobj = tobj->backing_object) {
 150                         if (tobj != obj)
 151                                 VM_OBJECT_RLOCK(tobj);
 152                         if (lobj != obj)
 153                                 VM_OBJECT_RUNLOCK(lobj);
 154                         lobj = tobj;
 155                 }
 156                 last_timestamp = map->timestamp;
 157                 vm_map_unlock_read(map);
 158
 159                 freepath = NULL;
 160                 fullpath = "-";
 161                 if (lobj) {
 162                         switch (lobj->type) {
 163                         default:
 164                         case OBJT_DEFAULT:
 165                                 type = "default";
 166                                 vp = NULL;
 167                                 break;
 168                         case OBJT_VNODE:
 169                                 type = "vnode";
 170                                 vp = lobj->handle;
 171                                 vref(vp);
 172                                 break;
 173                         case OBJT_SWAP:
 174                                 type = "swap";
 175                                 vp = NULL;
 176                                 break;
 177                         case OBJT_SG:
 178                         case OBJT_DEVICE:
 179                                 type = "device";
 180                                 vp = NULL;
 181                                 break;
 182                         }
 183                         if (lobj != obj)
 184                                 VM_OBJECT_RUNLOCK(lobj);
 185
 186                         flags = obj->flags;
 187                         ref_count = obj->ref_count;
 188                         shadow_count = obj->shadow_count;
 189                         VM_OBJECT_RUNLOCK(obj);
 190                         if (vp != NULL) {
 191                                 vn_fullpath(td, vp, &fullpath, &freepath);
 192                                 vrele(vp);
 193                         }
 194                 } else {
 195                         type = "none";
 196                         flags = 0;
 197                         ref_count = 0;
 198                         shadow_count = 0;
 199                 }
 200
 201                 /*
 202                  * format:
 203                  *  start, end, resident, private resident, cow, access, type,
 204                  *         charged, charged uid.
 205                  */
 206                 error = sbuf_printf(sb,
 207                     "0x%lx 0x%lx %d %d %p %s%s%s %d %d 0x%x %s %s %s %s %s %d\n",
 208                         (u_long)e_start, (u_long)e_end,
 209                         resident, privateresident,
 210 #ifdef COMPAT_FREEBSD32
 211                         wrap32 ? NULL : obj,    /* Hide 64 bit value */
 212 #else
 213                         obj,
 214 #endif
 215                         (e_prot & VM_PROT_READ)?"r":"-",
 216                         (e_prot & VM_PROT_WRITE)?"w":"-",
 217                         (e_prot & VM_PROT_EXECUTE)?"x":"-",
 218                         ref_count, shadow_count, flags,
 219                         (e_eflags & MAP_ENTRY_COW)?"COW":"NCOW",
 220                         (e_eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC",
 221                         type, fullpath,
 222                         cred ? "CH":"NCH", cred ? cred->cr_ruid : -1);
 223
 224                 if (freepath != NULL)
 225                         free(freepath, M_TEMP);
 226                 vm_map_lock_read(map);
 227                 if (error == -1) {
 228                         error = 0;
 229                         break;
 230                 }
 231                 if (last_timestamp != map->timestamp) {
 232                         /*
 233                          * Look again for the entry because the map was
 234                          * modified while it was unlocked.  Specifically,
 235                          * the entry may have been clipped, merged, or deleted.
 236                          */
 237                         vm_map_lookup_entry(map, e_end - 1, &tmp_entry);
 238                         entry = tmp_entry;
 239                 }
 240         }
 241         vm_map_unlock_read(map);
 242         vmspace_free(vm);
 243         return (error);
 244 }