osdep.c

   1 /*
   2  * QEMU low level functions
   3  *
   4  * Copyright (c) 2003 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <stdarg.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <unistd.h>
  30
  31 #include "cpu.h"
  32
  33 #if defined(__i386__) && !defined(CONFIG_SOFTMMU) && !defined(CONFIG_USER_ONLY)
  34
  35 #include <sys/mman.h>
  36 #include <sys/ipc.h>
  37
  38 /* When not using soft mmu, libc independant functions are needed for
  39    the CPU core because it needs to use alternates stacks and
  40    libc/thread incompatibles settings */
  41
  42 #include <linux/unistd.h>
  43
  44 #define QEMU_SYSCALL0(name) \
  45 { \
  46 long __res; \
  47 __asm__ volatile ("int $0x80" \
  48         : "=a" (__res) \
  49         : "0" (__NR_##name)); \
  50 return __res; \
  51 }
  52
  53 #define QEMU_SYSCALL1(name,arg1) \
  54 { \
  55 long __res; \
  56 __asm__ volatile ("int $0x80" \
  57         : "=a" (__res) \
  58         : "0" (__NR_##name),"b" ((long)(arg1))); \
  59 return __res; \
  60 }
  61
  62 #define QEMU_SYSCALL2(name,arg1,arg2) \
  63 { \
  64 long __res; \
  65 __asm__ volatile ("int $0x80" \
  66         : "=a" (__res) \
  67         : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2))); \
  68 return __res; \
  69 }
  70
  71 #define QEMU_SYSCALL3(name,arg1,arg2,arg3) \
  72 { \
  73 long __res; \
  74 __asm__ volatile ("int $0x80" \
  75         : "=a" (__res) \
  76         : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \
  77                   "d" ((long)(arg3))); \
  78 return __res; \
  79 }
  80
  81 #define QEMU_SYSCALL4(name,arg1,arg2,arg3,arg4) \
  82 { \
  83 long __res; \
  84 __asm__ volatile ("int $0x80" \
  85         : "=a" (__res) \
  86         : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \
  87           "d" ((long)(arg3)),"S" ((long)(arg4))); \
  88 return __res; \
  89 }
  90
  91 #define QEMU_SYSCALL5(name,arg1,arg2,arg3,arg4,arg5) \
  92 { \
  93 long __res; \
  94 __asm__ volatile ("int $0x80" \
  95         : "=a" (__res) \
  96         : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \
  97           "d" ((long)(arg3)),"S" ((long)(arg4)),"D" ((long)(arg5))); \
  98 return __res; \
  99 }
 100
 101 #define QEMU_SYSCALL6(name,arg1,arg2,arg3,arg4,arg5,arg6) \
 102 { \
 103 long __res; \
 104 __asm__ volatile ("push %%ebp ; movl %%eax,%%ebp ; movl %1,%%eax ; int $0x80 ; pop %%ebp" \
 105         : "=a" (__res) \
 106         : "i" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \
 107           "d" ((long)(arg3)),"S" ((long)(arg4)),"D" ((long)(arg5)), \
 108           "0" ((long)(arg6))); \
 109 return __res; \
 110 }
 111
 112 int qemu_write(int fd, const void *buf, size_t n)
 113 {
 114     QEMU_SYSCALL3(write, fd, buf, n);
 115 }
 116
 117
 118
 119 /****************************************************************/
 120 /* shmat replacement */
 121
 122 int qemu_ipc(int call, unsigned long first,
 123             unsigned long second, unsigned long third,
 124             void *ptr, unsigned long fifth)
 125 {
 126     QEMU_SYSCALL6(ipc, call, first, second, third, ptr, fifth);
 127 }
 128
 129 #define SHMAT 21
 130
 131 /* we must define shmat so that a specific address will be used when
 132    mapping the X11 ximage */
 133 void *shmat(int shmid, const void *shmaddr, int shmflg)
 134 {
 135     void *ptr;
 136     int ret;
 137     /* we give an address in the right memory area */
 138     if (!shmaddr)
 139         shmaddr = get_mmap_addr(8192 * 1024);
 140     ret = qemu_ipc(SHMAT, shmid, shmflg, (unsigned long)&ptr, (void *)shmaddr, 0);
 141     if (ret < 0)
 142         return NULL;
 143     return ptr;
 144 }
 145
 146 /****************************************************************/
 147 /* sigaction bypassing the threads */
 148
 149 static int kernel_sigaction(int signum, const struct qemu_sigaction *act,
 150                             struct qemu_sigaction *oldact,
 151                             int sigsetsize)
 152 {
 153     QEMU_SYSCALL4(rt_sigaction, signum, act, oldact, sigsetsize);
 154 }
 155
 156 int qemu_sigaction(int signum, const struct qemu_sigaction *act,
 157                    struct qemu_sigaction *oldact)
 158 {
 159     return kernel_sigaction(signum, act, oldact, 8);
 160 }
 161
 162 /****************************************************************/
 163 /* memory allocation */
 164
 165 //#define DEBUG_MALLOC
 166
 167 #define MALLOC_BASE       0xab000000
 168 #define PHYS_RAM_BASE     0xac000000
 169
 170 #define MALLOC_ALIGN      16
 171 #define BLOCK_HEADER_SIZE 16
 172
 173 typedef struct MemoryBlock {
 174     struct MemoryBlock *next;
 175     unsigned long size; /* size of block, including header */
 176 } MemoryBlock;
 177
 178 static MemoryBlock *first_free_block;
 179 static unsigned long malloc_addr = MALLOC_BASE;
 180
 181 static void *malloc_get_space(size_t size)
 182 {
 183     void *ptr;
 184     size = TARGET_PAGE_ALIGN(size);
 185     ptr = mmap((void *)malloc_addr, size,
 186                PROT_WRITE | PROT_READ,
 187                MAP_PRIVATE | MAP_FIXED | MAP_ANON, -1, 0);
 188     if (ptr == MAP_FAILED)
 189         return NULL;
 190     malloc_addr += size;
 191     return ptr;
 192 }
 193
 194 void *qemu_malloc(size_t size)
 195 {
 196     MemoryBlock *mb, *mb1, **pmb;
 197     void *ptr;
 198     size_t size1, area_size;
 199
 200     if (size == 0)
 201         return NULL;
 202
 203     size = (size + BLOCK_HEADER_SIZE + MALLOC_ALIGN - 1) & ~(MALLOC_ALIGN - 1);
 204     pmb = &first_free_block;
 205     for(;;) {
 206         mb = *pmb;
 207         if (mb == NULL)
 208             break;
 209         if (size <= mb->size)
 210             goto found;
 211         pmb = &mb->next;
 212     }
 213     /* no big enough blocks found: get new space */
 214     area_size = TARGET_PAGE_ALIGN(size);
 215     mb = malloc_get_space(area_size);
 216     if (!mb)
 217         return NULL;
 218     size1 = area_size - size;
 219     if (size1 > 0) {
 220         /* create a new free block */
 221         mb1 = (MemoryBlock *)((uint8_t *)mb + size);
 222         mb1->next = NULL;
 223         mb1->size = size1;
 224         *pmb = mb1;
 225     }
 226     goto the_end;
 227  found:
 228     /* a free block was found: use it */
 229     size1 = mb->size - size;
 230     if (size1 > 0) {
 231         /* create a new free block */
 232         mb1 = (MemoryBlock *)((uint8_t *)mb + size);
 233         mb1->next = mb->next;
 234         mb1->size = size1;
 235         *pmb = mb1;
 236     } else {
 237         /* suppress the first block */
 238         *pmb = mb->next;
 239     }
 240  the_end:
 241     mb->size = size;
 242     mb->next = NULL;
 243     ptr = ((uint8_t *)mb + BLOCK_HEADER_SIZE);
 244 #ifdef DEBUG_MALLOC
 245     qemu_printf("malloc: size=0x%x ptr=0x%lx\n", size, (unsigned long)ptr);
 246 #endif
 247     return ptr;
 248 }
 249
 250 void qemu_free(void *ptr)
 251 {
 252     MemoryBlock *mb;
 253
 254     if (!ptr)
 255         return;
 256     mb = (MemoryBlock *)((uint8_t *)ptr - BLOCK_HEADER_SIZE);
 257     mb->next = first_free_block;
 258     first_free_block = mb;
 259 }
 260
 261 /****************************************************************/
 262 /* virtual memory allocation */
 263
 264 unsigned long mmap_addr = PHYS_RAM_BASE;
 265
 266 void *get_mmap_addr(unsigned long size)
 267 {
 268     unsigned long addr;
 269     addr = mmap_addr;
 270     mmap_addr += ((size + 4095) & ~4095) + 4096;
 271     return (void *)addr;
 272 }
 273
 274 #else
 275
 276 #ifdef _WIN32
 277 #include <windows.h>
 278 #elif defined(_BSD)
 279 #include <stdlib.h>
 280 #else
 281 #include <malloc.h>
 282 #endif
 283
 284 int qemu_write(int fd, const void *buf, size_t n)
 285 {
 286     int ret;
 287     ret = write(fd, buf, n);
 288     if (ret < 0)
 289         return -errno;
 290     else
 291         return ret;
 292 }
 293
 294 void *get_mmap_addr(unsigned long size)
 295 {
 296     return NULL;
 297 }
 298
 299 void qemu_free(void *ptr)
 300 {
 301     free(ptr);
 302 }
 303
 304 void *qemu_malloc(size_t size)
 305 {
 306     return malloc(size);
 307 }
 308
 309 #if defined(_WIN32)
 310
 311 void *qemu_vmalloc(size_t size)
 312 {
 313     /* FIXME: this is not exactly optimal solution since VirtualAlloc
 314        has 64Kb granularity, but at least it guarantees us that the
 315        memory is page aligned. */
 316     return VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
 317 }
 318
 319 void qemu_vfree(void *ptr)
 320 {
 321     VirtualFree(ptr, 0, MEM_RELEASE);
 322 }
 323
 324 #elif defined(USE_KQEMU)
 325
 326 #include <sys/vfs.h>
 327 #include <sys/mman.h>
 328 #include <fcntl.h>
 329
 330 void *qemu_vmalloc(size_t size)
 331 {
 332     static int phys_ram_fd = -1;
 333     static int phys_ram_size = 0;
 334     const char *tmpdir;
 335     char phys_ram_file[1024];
 336     void *ptr;
 337     struct statfs stfs;
 338
 339     if (phys_ram_fd < 0) {
 340         tmpdir = getenv("QEMU_TMPDIR");
 341         if (!tmpdir)
 342             tmpdir = "/dev/shm";
 343         if (statfs(tmpdir, &stfs) == 0) {
 344             int64_t free_space;
 345             int ram_mb;
 346
 347             extern int ram_size;
 348             free_space = (int64_t)stfs.f_bavail * stfs.f_bsize;
 349             if ((ram_size + 8192 * 1024) >= free_space) {
 350                 ram_mb = (ram_size / (1024 * 1024));
 351                 fprintf(stderr,
 352                         "You do not have enough space in '%s' for the %d MB of QEMU virtual RAM.\n",
 353                         tmpdir, ram_mb);
 354                 if (strcmp(tmpdir, "/dev/shm") == 0) {
 355                     fprintf(stderr, "To have more space available provided you have enough RAM and swap, do as root:\n"
 356                             "umount /dev/shm\n"
 357                             "mount -t tmpfs -o size=%dm none /dev/shm\n",
 358                             ram_mb + 16);
 359                 } else {
 360                     fprintf(stderr,
 361                             "Use the '-m' option of QEMU to diminish the amount of virtual RAM or use the\n"
 362                             "QEMU_TMPDIR environment variable to set another directory where the QEMU\n"
 363                             "temporary RAM file will be opened.\n");
 364                 }
 365                 exit(1);
 366             }
 367         }
 368         snprintf(phys_ram_file, sizeof(phys_ram_file), "%s/qemuXXXXXX",
 369                  tmpdir);
 370         if (mkstemp(phys_ram_file) < 0) {
 371             fprintf(stderr,
 372                     "warning: could not create temporary file in '%s'.\n"
 373                     "Use QEMU_TMPDIR to select a directory in a tmpfs filesystem.\n"
 374                     "Using '/tmp' as fallback.\n",
 375                     tmpdir);
 376             snprintf(phys_ram_file, sizeof(phys_ram_file), "%s/qemuXXXXXX",
 377                      "/tmp");
 378             if (mkstemp(phys_ram_file) < 0) {
 379                 fprintf(stderr, "Could not create temporary memory file '%s'\n",
 380                         phys_ram_file);
 381                 exit(1);
 382             }
 383         }
 384         phys_ram_fd = open(phys_ram_file, O_CREAT | O_TRUNC | O_RDWR, 0600);
 385         if (phys_ram_fd < 0) {
 386             fprintf(stderr, "Could not open temporary memory file '%s'\n",
 387                     phys_ram_file);
 388             exit(1);
 389         }
 390         unlink(phys_ram_file);
 391     }
 392     size = (size + 4095) & ~4095;
 393     ftruncate(phys_ram_fd, phys_ram_size + size);
 394     ptr = mmap(NULL,
 395                size,
 396                PROT_WRITE | PROT_READ, MAP_SHARED,
 397                phys_ram_fd, phys_ram_size);
 398     if (ptr == MAP_FAILED) {
 399         fprintf(stderr, "Could not map physical memory\n");
 400         exit(1);
 401     }
 402     phys_ram_size += size;
 403     return ptr;
 404 }
 405
 406 void qemu_vfree(void *ptr)
 407 {
 408     /* may be useful some day, but currently we do not need to free */
 409 }
 410
 411 #else
 412
 413 /* alloc shared memory pages */
 414 void *qemu_vmalloc(size_t size)
 415 {
 416 #ifdef _BSD
 417     return valloc(size);
 418 #else
 419     return memalign(4096, size);
 420 #endif
 421 }
 422
 423 void qemu_vfree(void *ptr)
 424 {
 425     free(ptr);
 426 }
 427
 428 #endif
 429
 430 #endif
 431
 432 void *qemu_mallocz(size_t size)
 433 {
 434     void *ptr;
 435     ptr = qemu_malloc(size);
 436     if (!ptr)
 437         return NULL;
 438     memset(ptr, 0, size);
 439     return ptr;
 440 }
 441
 442 char *qemu_strdup(const char *str)
 443 {
 444     char *ptr;
 445     ptr = qemu_malloc(strlen(str) + 1);
 446     if (!ptr)
 447         return NULL;
 448     strcpy(ptr, str);
 449     return ptr;
 450 }
 451
 452 /****************************************************************/
 453 /* printf support */
 454
 455 static inline int qemu_isdigit(int c)
 456 {
 457     return c >= '0' && c <= '9';
 458 }
 459
 460 #define OUTCHAR(c)      (buflen > 0? (--buflen, *buf++ = (c)): 0)
 461
 462 /* from BSD ppp sources */
 463 int qemu_vsnprintf(char *buf, int buflen, const char *fmt, va_list args)
 464 {
 465     int c, i, n;
 466     int width, prec, fillch;
 467     int base, len, neg;
 468     unsigned long val = 0;
 469     const char *f;
 470     char *str, *buf0;
 471     char num[32];
 472     static const char hexchars[] = "0123456789abcdef";
 473
 474     buf0 = buf;
 475     --buflen;
 476     while (buflen > 0) {
 477         for (f = fmt; *f != '%' && *f != 0; ++f)
 478             ;
 479         if (f > fmt) {
 480             len = f - fmt;
 481             if (len > buflen)
 482                 len = buflen;
 483             memcpy(buf, fmt, len);
 484             buf += len;
 485             buflen -= len;
 486             fmt = f;
 487         }
 488         if (*fmt == 0)
 489             break;
 490         c = *++fmt;
 491         width = prec = 0;
 492         fillch = ' ';
 493         if (c == '0') {
 494             fillch = '0';
 495             c = *++fmt;
 496         }
 497         if (c == '*') {
 498             width = va_arg(args, int);
 499             c = *++fmt;
 500         } else {
 501             while (qemu_isdigit(c)) {
 502                 width = width * 10 + c - '0';
 503                 c = *++fmt;
 504             }
 505         }
 506         if (c == '.') {
 507             c = *++fmt;
 508             if (c == '*') {
 509                 prec = va_arg(args, int);
 510                 c = *++fmt;
 511             } else {
 512                 while (qemu_isdigit(c)) {
 513                     prec = prec * 10 + c - '0';
 514                     c = *++fmt;
 515                 }
 516             }
 517         }
 518         /* modifiers */
 519         switch(c) {
 520         case 'l':
 521             c = *++fmt;
 522             break;
 523         default:
 524             break;
 525         }
 526         str = 0;
 527         base = 0;
 528         neg = 0;
 529         ++fmt;
 530         switch (c) {
 531         case 'd':
 532             i = va_arg(args, int);
 533             if (i < 0) {
 534                 neg = 1;
 535                 val = -i;
 536             } else
 537                 val = i;
 538             base = 10;
 539             break;
 540         case 'o':
 541             val = va_arg(args, unsigned int);
 542             base = 8;
 543             break;
 544         case 'x':
 545         case 'X':
 546             val = va_arg(args, unsigned int);
 547             base = 16;
 548             break;
 549         case 'p':
 550             val = (unsigned long) va_arg(args, void *);
 551             base = 16;
 552             neg = 2;
 553             break;
 554         case 's':
 555             str = va_arg(args, char *);
 556             break;
 557         case 'c':
 558             num[0] = va_arg(args, int);
 559             num[1] = 0;
 560             str = num;
 561             break;
 562         default:
 563             *buf++ = '%';
 564             if (c != '%')
 565                 --fmt;          /* so %z outputs %z etc. */
 566             --buflen;
 567             continue;
 568         }
 569         if (base != 0) {
 570             str = num + sizeof(num);
 571             *--str = 0;
 572             while (str > num + neg) {
 573                 *--str = hexchars[val % base];
 574                 val = val / base;
 575                 if (--prec <= 0 && val == 0)
 576                     break;
 577             }
 578             switch (neg) {
 579             case 1:
 580                 *--str = '-';
 581                 break;
 582             case 2:
 583                 *--str = 'x';
 584                 *--str = '0';
 585                 break;
 586             }
 587             len = num + sizeof(num) - 1 - str;
 588         } else {
 589             len = strlen(str);
 590             if (prec > 0 && len > prec)
 591                 len = prec;
 592         }
 593         if (width > 0) {
 594             if (width > buflen)
 595                 width = buflen;
 596             if ((n = width - len) > 0) {
 597                 buflen -= n;
 598                 for (; n > 0; --n)
 599                     *buf++ = fillch;
 600             }
 601         }
 602         if (len > buflen)
 603             len = buflen;
 604         memcpy(buf, str, len);
 605         buf += len;
 606         buflen -= len;
 607     }
 608     *buf = 0;
 609     return buf - buf0;
 610 }
 611
 612 void qemu_vprintf(const char *fmt, va_list ap)
 613 {
 614     char buf[1024];
 615     int len;
 616
 617     len = qemu_vsnprintf(buf, sizeof(buf), fmt, ap);
 618     qemu_write(1, buf, len);
 619 }
 620
 621 void qemu_printf(const char *fmt, ...)
 622 {
 623     va_list ap;
 624     va_start(ap, fmt);
 625     qemu_vprintf(fmt, ap);
 626     va_end(ap);
 627 }
 628