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/mutex.h>
  47 #include <sys/proc.h>
  48 #include <sys/sbuf.h>
  49 #include <sys/uio.h>
  50 #include <sys/vnode.h>
  51
  52 #include <fs/pseudofs/pseudofs.h>
  53 #include <fs/procfs/procfs.h>
  54
  55 #include <vm/vm.h>
  56 #include <vm/vm_extern.h>
  57 #include <vm/pmap.h>
  58 #include <vm/vm_map.h>
  59 #include <vm/vm_page.h>
  60 #include <vm/vm_object.h>
  61
  62 #ifdef COMPAT_IA32
  63 #include <sys/procfs.h>
  64 #include <machine/fpu.h>
  65 #include <compat/ia32/ia32_reg.h>
  66
  67 extern struct sysentvec ia32_freebsd_sysvec;
  68 #endif
  69
  70
  71 #define MEBUFFERSIZE 256
  72
  73 /*
  74  * The map entries can *almost* be read with programs like cat.  However,
  75  * large maps need special programs to read.  It is not easy to implement
  76  * a program that can sense the required size of the buffer, and then
  77  * subsequently do a read with the appropriate size.  This operation cannot
  78  * be atomic.  The best that we can do is to allow the program to do a read
  79  * with an arbitrarily large buffer, and return as much as we can.  We can
  80  * return an error code if the buffer is too small (EFBIG), then the program
  81  * can try a bigger buffer.
  82  */
  83 int
  84 procfs_doprocmap(PFS_FILL_ARGS)
  85 {
  86         struct vmspace *vm;
  87         vm_map_t map;
  88         vm_map_entry_t entry, tmp_entry;
  89         struct vnode *vp;
  90         char *fullpath, *freepath;
  91         int error, vfslocked;
  92         unsigned int last_timestamp;
  93 #ifdef COMPAT_IA32
  94         int wrap32 = 0;
  95 #endif
  96
  97         PROC_LOCK(p);
  98         error = p_candebug(td, p);
  99         PROC_UNLOCK(p);
 100         if (error)
 101                 return (error);
 102
 103         if (uio->uio_rw != UIO_READ)
 104                 return (EOPNOTSUPP);
 105
 106 #ifdef COMPAT_IA32
 107         if (curthread->td_proc->p_sysent == &ia32_freebsd_sysvec) {
 108                 if (p->p_sysent != &ia32_freebsd_sysvec)
 109                         return (EOPNOTSUPP);
 110                 wrap32 = 1;
 111         }
 112 #endif
 113
 114         vm = vmspace_acquire_ref(p);
 115         if (vm == NULL)
 116                 return (ESRCH);
 117         map = &vm->vm_map;
 118         vm_map_lock_read(map);
 119         for (entry = map->header.next; entry != &map->header;
 120              entry = entry->next) {
 121                 vm_object_t obj, tobj, lobj;
 122                 int ref_count, shadow_count, flags;
 123                 vm_offset_t e_start, e_end, addr;
 124                 int resident, privateresident;
 125                 char *type;
 126                 vm_eflags_t e_eflags;
 127                 vm_prot_t e_prot;
 128
 129                 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP)
 130                         continue;
 131
 132                 e_eflags = entry->eflags;
 133                 e_prot = entry->protection;
 134                 e_start = entry->start;
 135                 e_end = entry->end;
 136                 privateresident = 0;
 137                 obj = entry->object.vm_object;
 138                 if (obj != NULL) {
 139                         VM_OBJECT_LOCK(obj);
 140                         if (obj->shadow_count == 1)
 141                                 privateresident = obj->resident_page_count;
 142                 }
 143
 144                 resident = 0;
 145                 addr = entry->start;
 146                 while (addr < entry->end) {
 147                         if (pmap_extract(map->pmap, addr))
 148                                 resident++;
 149                         addr += PAGE_SIZE;
 150                 }
 151
 152                 for (lobj = tobj = obj; tobj; tobj = tobj->backing_object) {
 153                         if (tobj != obj)
 154                                 VM_OBJECT_LOCK(tobj);
 155                         if (lobj != obj)
 156                                 VM_OBJECT_UNLOCK(lobj);
 157                         lobj = tobj;
 158                 }
 159                 last_timestamp = map->timestamp;
 160                 vm_map_unlock_read(map);
 161
 162                 freepath = NULL;
 163                 fullpath = "-";
 164                 if (lobj) {
 165                         switch (lobj->type) {
 166                         default:
 167                         case OBJT_DEFAULT:
 168                                 type = "default";
 169                                 vp = NULL;
 170                                 break;
 171                         case OBJT_VNODE:
 172                                 type = "vnode";
 173                                 vp = lobj->handle;
 174                                 vref(vp);
 175                                 break;
 176                         case OBJT_SWAP:
 177                                 type = "swap";
 178                                 vp = NULL;
 179                                 break;
 180                         case OBJT_DEVICE:
 181                                 type = "device";
 182                                 vp = NULL;
 183                                 break;
 184                         }
 185                         if (lobj != obj)
 186                                 VM_OBJECT_UNLOCK(lobj);
 187
 188                         flags = obj->flags;
 189                         ref_count = obj->ref_count;
 190                         shadow_count = obj->shadow_count;
 191                         VM_OBJECT_UNLOCK(obj);
 192                         if (vp != NULL) {
 193                                 vn_fullpath(td, vp, &fullpath, &freepath);
 194                                 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 195                                 vrele(vp);
 196                                 VFS_UNLOCK_GIANT(vfslocked);
 197                         }
 198                 } else {
 199                         type = "none";
 200                         flags = 0;
 201                         ref_count = 0;
 202                         shadow_count = 0;
 203                 }
 204
 205                 /*
 206                  * format:
 207                  *  start, end, resident, private resident, cow, access, type.
 208                  */
 209                 error = sbuf_printf(sb,
 210                     "0x%lx 0x%lx %d %d %p %s%s%s %d %d 0x%x %s %s %s %s\n",
 211                         (u_long)e_start, (u_long)e_end,
 212                         resident, privateresident,
 213 #ifdef COMPAT_IA32
 214                         wrap32 ? NULL : obj,    /* Hide 64 bit value */
 215 #else
 216                         obj,
 217 #endif
 218                         (e_prot & VM_PROT_READ)?"r":"-",
 219                         (e_prot & VM_PROT_WRITE)?"w":"-",
 220                         (e_prot & VM_PROT_EXECUTE)?"x":"-",
 221                         ref_count, shadow_count, flags,
 222                         (e_eflags & MAP_ENTRY_COW)?"COW":"NCOW",
 223                         (e_eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC",
 224                         type, fullpath);
 225
 226                 if (freepath != NULL)
 227                         free(freepath, M_TEMP);
 228                 vm_map_lock_read(map);
 229                 if (error == -1) {
 230                         error = 0;
 231                         break;
 232                 }
 233                 if (last_timestamp != map->timestamp) {
 234                         /*
 235                          * Look again for the entry because the map was
 236                          * modified while it was unlocked.  Specifically,
 237                          * the entry may have been clipped, merged, or deleted.
 238                          */
 239                         vm_map_lookup_entry(map, e_end - 1, &tmp_entry);
 240                         entry = tmp_entry;
 241                 }
 242         }
 243         vm_map_unlock_read(map);
 244         vmspace_free(vm);
 245         return (error);
 246 }