servers/vm/mmap.c

   1
   2 #define _SYSTEM 1
   3
   4 #include <minix/callnr.h>
   5 #include <minix/com.h>
   6 #include <minix/config.h>
   7 #include <minix/const.h>
   8 #include <minix/ds.h>
   9 #include <minix/endpoint.h>
  10 #include <minix/keymap.h>
  11 #include <minix/minlib.h>
  12 #include <minix/type.h>
  13 #include <minix/ipc.h>
  14 #include <minix/sysutil.h>
  15 #include <minix/syslib.h>
  16 #include <minix/safecopies.h>
  17 #include <minix/bitmap.h>
  18 #include <minix/debug.h>
  19
  20 #include <sys/mman.h>
  21 #include <sys/param.h>
  22
  23 #include <errno.h>
  24 #include <assert.h>
  25 #include <string.h>
  26 #include <env.h>
  27 #include <stdio.h>
  28 #include <fcntl.h>
  29 #include <memory.h>
  30
  31 #include "glo.h"
  32 #include "proto.h"
  33 #include "util.h"
  34 #include "region.h"
  35
  36 /*===========================================================================*
  37  *                              do_mmap                                      *
  38  *===========================================================================*/
  39 int do_mmap(message *m)
  40 {
  41         int r, n;
  42         struct vmproc *vmp;
  43         int mfflags = 0;
  44         vir_bytes addr;
  45         struct vir_region *vr = NULL;
  46         int execpriv = 0;
  47
  48         /* RS and VFS can do slightly more special mmap() things */
  49         if(m->m_source == VFS_PROC_NR || m->m_source == RS_PROC_NR)
  50                 execpriv = 1;
  51
  52         if(m->VMM_FLAGS & MAP_THIRDPARTY) {
  53                 if(!execpriv) return EPERM;
  54                 if((r=vm_isokendpt(m->VMM_FORWHOM, &n)) != OK)
  55                         return ESRCH;
  56         } else {
  57                 /* regular mmap, i.e. for caller */
  58                 if((r=vm_isokendpt(m->m_source, &n)) != OK) {
  59                         panic("do_mmap: message from strange source: %d",
  60                                 m->m_source);
  61                 }
  62         }
  63
  64         vmp = &vmproc[n];
  65
  66         if(m->VMM_FD == -1 || (m->VMM_FLAGS & MAP_ANON)) {
  67                 u32_t vrflags = VR_ANON | VR_WRITABLE;
  68                 size_t len = (vir_bytes) m->VMM_LEN;
  69
  70                 if(m->VMM_FD != -1 || len <= 0) {
  71                         return EINVAL;
  72                 }
  73
  74                 /* Contiguous phys memory has to be preallocated. */
  75                 if((m->VMM_FLAGS & (MAP_CONTIG|MAP_PREALLOC)) == MAP_CONTIG) {
  76                         return EINVAL;
  77                 }
  78
  79                 if(m->VMM_FLAGS & MAP_PREALLOC) mfflags |= MF_PREALLOC;
  80                 if(m->VMM_FLAGS & MAP_LOWER16M) vrflags |= VR_LOWER16MB;
  81                 if(m->VMM_FLAGS & MAP_LOWER1M)  vrflags |= VR_LOWER1MB;
  82                 if(m->VMM_FLAGS & MAP_ALIGN64K) vrflags |= VR_PHYS64K;
  83                 if(m->VMM_FLAGS & MAP_UNINITIALIZED) {
  84                         if(!execpriv) return EPERM;
  85                         vrflags |= VR_UNINITIALIZED;
  86                 }
  87                 if(m->VMM_FLAGS & MAP_IPC_SHARED) {
  88                         vrflags |= VR_SHARED;
  89                         /* Shared memory has to be preallocated. */
  90                         if((m->VMM_FLAGS & (MAP_PREALLOC|MAP_ANON)) !=
  91                                 (MAP_PREALLOC|MAP_ANON)) {
  92                                 return EINVAL;
  93                         }
  94                 }
  95                 if(m->VMM_FLAGS & MAP_CONTIG) vrflags |= VR_CONTIG;
  96
  97                 if(len % VM_PAGE_SIZE)
  98                         len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
  99
 100                 vr = NULL;
 101                 if (m->VMM_ADDR || (m->VMM_FLAGS & MAP_FIXED)) {
 102                         /* An address is given, first try at that address. */
 103                         addr = m->VMM_ADDR;
 104                         vr = map_page_region(vmp, addr, 0, len, MAP_NONE,
 105                                 vrflags, mfflags);
 106                         if(!vr && (m->VMM_FLAGS & MAP_FIXED))
 107                                 return ENOMEM;
 108                 }
 109                 if (!vr) {
 110                         /* No address given or address already in use. */
 111                         vr = map_page_region(vmp, 0, VM_DATATOP, len,
 112                                 MAP_NONE, vrflags, mfflags);
 113                 }
 114                 if (!vr) {
 115                         return ENOMEM;
 116                 }
 117         } else {
 118                 return ENOSYS;
 119         }
 120
 121         /* Return mapping, as seen from process. */
 122         assert(vr);
 123         m->VMM_RETADDR = vr->vaddr;
 124
 125
 126         return OK;
 127 }
 128
 129 /*===========================================================================*
 130  *                              map_perm_check                               *
 131  *===========================================================================*/
 132 int map_perm_check(endpoint_t caller, endpoint_t target,
 133         phys_bytes physaddr, phys_bytes len)
 134 {
 135         int r;
 136
 137         /* TTY and memory are allowed to do anything.
 138          * They have to be special cases as they have to be able to do
 139          * anything; TTY even on behalf of anyone for the TIOCMAPMEM
 140          * ioctl. MEM just for itself.
 141          */
 142         if(caller == TTY_PROC_NR)
 143                 return OK;
 144         if(caller != target)
 145                 return EPERM;
 146         if(caller == MEM_PROC_NR)
 147                 return OK;
 148
 149         /* Anyone else needs explicit permission from the kernel (ultimately
 150          * set by PCI).
 151          */
 152         r = sys_privquery_mem(caller, physaddr, len);
 153
 154         return r;
 155 }
 156
 157 /*===========================================================================*
 158  *                              do_map_phys                                  *
 159  *===========================================================================*/
 160 int do_map_phys(message *m)
 161 {
 162         int r, n;
 163         struct vmproc *vmp;
 164         endpoint_t target;
 165         struct vir_region *vr;
 166         vir_bytes len;
 167         phys_bytes startaddr;
 168         size_t offset;
 169
 170         target = m->VMMP_EP;
 171         len = m->VMMP_LEN;
 172
 173         if (len <= 0) return EINVAL;
 174
 175         if(target == SELF)
 176                 target = m->m_source;
 177
 178         if((r=vm_isokendpt(target, &n)) != OK)
 179                 return EINVAL;
 180
 181         startaddr = (vir_bytes)m->VMMP_PHADDR;
 182
 183         /* First check permission, then round range down/up. Caller can't
 184          * help it if we can't map in lower than page granularity.
 185          */
 186         if(map_perm_check(m->m_source, target, startaddr, len) != OK) {
 187                 printf("VM: unauthorized mapping of 0x%lx by %d\n",
 188                         startaddr, m->m_source);
 189                 return EPERM;
 190         }
 191
 192         vmp = &vmproc[n];
 193
 194         offset = startaddr % VM_PAGE_SIZE;
 195         len += offset;
 196         startaddr -= offset;
 197
 198         if(len % VM_PAGE_SIZE)
 199                 len += VM_PAGE_SIZE - (len % VM_PAGE_SIZE);
 200
 201         if(!(vr = map_page_region(vmp, 0, VM_DATATOP, len, startaddr,
 202                 VR_DIRECT | VR_NOPF | VR_WRITABLE, 0))) {
 203                 return ENOMEM;
 204         }
 205
 206         m->VMMP_VADDR_REPLY = (void *) (vr->vaddr + offset);
 207
 208         return OK;
 209 }
 210
 211 /*===========================================================================*
 212  *                              do_unmap_phys                                *
 213  *===========================================================================*/
 214 int do_unmap_phys(message *m)
 215 {
 216         int r, n;
 217         struct vmproc *vmp;
 218         endpoint_t target;
 219         struct vir_region *region;
 220
 221         target = m->VMUP_EP;
 222         if(target == SELF)
 223                 target = m->m_source;
 224
 225         if((r=vm_isokendpt(target, &n)) != OK)
 226                 return EINVAL;
 227
 228         vmp = &vmproc[n];
 229
 230         if(!(region = map_lookup(vmp, (vir_bytes) m->VMUM_ADDR, NULL))) {
 231                 return EINVAL;
 232         }
 233
 234         if(!(region->flags & VR_DIRECT)) {
 235                 return EINVAL;
 236         }
 237
 238         if(map_unmap_region(vmp, region, 0, region->length) != OK) {
 239                 return EINVAL;
 240         }
 241
 242         return OK;
 243 }
 244
 245 /*===========================================================================*
 246  *                              do_remap                                     *
 247  *===========================================================================*/
 248 int do_remap(message *m)
 249 {
 250         int dn, sn;
 251         vir_bytes da, sa, startv;
 252         size_t size;
 253         struct vir_region *region;
 254         struct vmproc *dvmp, *svmp;
 255         int r;
 256         int readonly;
 257
 258         if(m->m_type == VM_REMAP)
 259                 readonly = 0;
 260         else if(m->m_type == VM_REMAP_RO)
 261                 readonly = 1;
 262         else panic("do_remap: can't be");
 263
 264         da = (vir_bytes) m->VMRE_DA;
 265         sa = (vir_bytes) m->VMRE_SA;
 266         size = m->VMRE_SIZE;
 267
 268         if (size <= 0) return EINVAL;
 269
 270         if ((r = vm_isokendpt((endpoint_t) m->VMRE_D, &dn)) != OK)
 271                 return EINVAL;
 272         if ((r = vm_isokendpt((endpoint_t) m->VMRE_S, &sn)) != OK)
 273                 return EINVAL;
 274
 275         dvmp = &vmproc[dn];
 276         svmp = &vmproc[sn];
 277
 278         /* da is not translated by arch_vir2map(),
 279          * it's handled a little differently,
 280          * since in map_remap(), we have to know
 281          * about whether the user needs to bind to
 282          * THAT address or be chosen by the system.
 283          */
 284         if (!(region = map_lookup(svmp, sa, NULL)))
 285                 return EINVAL;
 286
 287         if(region->vaddr != sa) {
 288                 printf("VM: do_remap: not start of region.\n");
 289                 return EFAULT;
 290         }
 291
 292         if(!(region->flags & VR_SHARED)) {
 293                 printf("VM: do_remap: not shared.\n");
 294                 return EFAULT;
 295         }
 296
 297         if (size % VM_PAGE_SIZE)
 298                 size += VM_PAGE_SIZE - size % VM_PAGE_SIZE;
 299
 300         if(size != region->length) {
 301                 printf("VM: do_remap: not size of region.\n");
 302                 return EFAULT;
 303         }
 304
 305         if ((r = map_remap(dvmp, da, size, region, &startv, readonly)) != OK)
 306                 return r;
 307
 308         m->VMRE_RETA = (char *) startv;
 309         return OK;
 310 }
 311
 312 /*===========================================================================*
 313  *                              do_shared_unmap                              *
 314  *===========================================================================*/
 315 int do_shared_unmap(message *m)
 316 {
 317         int r, n;
 318         struct vmproc *vmp;
 319         endpoint_t target;
 320         struct vir_region *vr;
 321         vir_bytes addr;
 322
 323         target = m->VMUN_ENDPT;
 324         if (target == SELF)
 325                 target = m->m_source;
 326
 327         if ((r = vm_isokendpt(target, &n)) != OK)
 328                 return EINVAL;
 329
 330         vmp = &vmproc[n];
 331
 332         addr = m->VMUN_ADDR;
 333
 334         if(!(vr = map_lookup(vmp, addr, NULL))) {
 335                 printf("VM: addr 0x%lx not found.\n", m->VMUN_ADDR);
 336                 return EFAULT;
 337         }
 338
 339         if(vr->vaddr != addr) {
 340                 printf("VM: wrong address for shared_unmap.\n");
 341                 return EFAULT;
 342         }
 343
 344         if(!(vr->flags & VR_SHARED)) {
 345                 printf("VM: address does not point to shared region.\n");
 346                 return EFAULT;
 347         }
 348
 349         if(map_unmap_region(vmp, vr, 0, vr->length) != OK)
 350                 panic("do_shared_unmap: map_unmap_region failed");
 351
 352         return OK;
 353 }
 354
 355 /*===========================================================================*
 356  *                              do_get_phys                                  *
 357  *===========================================================================*/
 358 int do_get_phys(message *m)
 359 {
 360         int r, n;
 361         struct vmproc *vmp;
 362         endpoint_t target;
 363         phys_bytes ret;
 364         vir_bytes addr;
 365
 366         target = m->VMPHYS_ENDPT;
 367         addr = m->VMPHYS_ADDR;
 368
 369         if ((r = vm_isokendpt(target, &n)) != OK)
 370                 return EINVAL;
 371
 372         vmp = &vmproc[n];
 373
 374         r = map_get_phys(vmp, addr, &ret);
 375
 376         m->VMPHYS_RETA = ret;
 377         return r;
 378 }
 379
 380 /*===========================================================================*
 381  *                              do_get_refcount                              *
 382  *===========================================================================*/
 383 int do_get_refcount(message *m)
 384 {
 385         int r, n;
 386         struct vmproc *vmp;
 387         endpoint_t target;
 388         u8_t cnt;
 389         vir_bytes addr;
 390
 391         target = m->VMREFCNT_ENDPT;
 392         addr = m->VMREFCNT_ADDR;
 393
 394         if ((r = vm_isokendpt(target, &n)) != OK)
 395                 return EINVAL;
 396
 397         vmp = &vmproc[n];
 398
 399         r = map_get_ref(vmp, addr, &cnt);
 400
 401         m->VMREFCNT_RETC = cnt;
 402         return r;
 403 }
 404
 405 /*===========================================================================*
 406  *                              do_munmap                                    *
 407  *===========================================================================*/
 408 int do_munmap(message *m)
 409 {
 410         int r, n;
 411         struct vmproc *vmp;
 412         vir_bytes addr, len, offset;
 413         struct vir_region *vr;
 414
 415         if((r=vm_isokendpt(m->m_source, &n)) != OK) {
 416                 panic("do_mmap: message from strange source: %d", m->m_source);
 417         }
 418
 419         vmp = &vmproc[n];
 420
 421         assert(m->m_type == VM_MUNMAP);
 422         addr = (vir_bytes) (vir_bytes) m->VMUM_ADDR;
 423
 424         if(!(vr = map_lookup(vmp, addr, NULL))) {
 425                 printf("VM: unmap: virtual address %p not found in %d\n",
 426                         m->VMUM_ADDR, vmp->vm_endpoint);
 427                 return EFAULT;
 428         }
 429
 430         if(addr % VM_PAGE_SIZE)
 431                 return EFAULT;
 432
 433         len = roundup(m->VMUM_LEN, VM_PAGE_SIZE);
 434
 435         offset = addr - vr->vaddr;
 436
 437         if(offset + len > vr->length) {
 438                 printf("munmap: addr 0x%lx len 0x%lx spills out of region\n",
 439                         addr, len);
 440                 return EFAULT;
 441         }
 442
 443         if(map_unmap_region(vmp, vr, offset, len) != OK)
 444                 panic("do_munmap: map_unmap_region failed");
 445
 446         return OK;
 447 }
 448