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 #include <fcntl.h>
  31 #ifdef HOST_SOLARIS
  32 #include <sys/types.h>
  33 #include <sys/statvfs.h>
  34 #endif
  35
  36 #include "qemu-common.h"
  37 #include "sysemu.h"
  38
  39 #ifdef _WIN32
  40 #define WIN32_LEAN_AND_MEAN
  41 #include <windows.h>
  42 #elif defined(_BSD)
  43 #include <stdlib.h>
  44 #else
  45 #include <malloc.h>
  46 #endif
  47
  48 #if defined(_WIN32)
  49 void *qemu_memalign(size_t alignment, size_t size)
  50 {
  51     return VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
  52 }
  53
  54 void *qemu_vmalloc(size_t size)
  55 {
  56     /* FIXME: this is not exactly optimal solution since VirtualAlloc
  57        has 64Kb granularity, but at least it guarantees us that the
  58        memory is page aligned. */
  59     return VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
  60 }
  61
  62 void qemu_vfree(void *ptr)
  63 {
  64     VirtualFree(ptr, 0, MEM_RELEASE);
  65 }
  66
  67 #else
  68
  69 #if defined(USE_KQEMU)
  70
  71 #include <sys/vfs.h>
  72 #include <sys/mman.h>
  73 #include <fcntl.h>
  74
  75 static void *kqemu_vmalloc(size_t size)
  76 {
  77     static int phys_ram_fd = -1;
  78     static int phys_ram_size = 0;
  79     const char *tmpdir;
  80     char phys_ram_file[1024];
  81     void *ptr;
  82 #ifdef HOST_SOLARIS
  83     struct statvfs stfs;
  84 #else
  85     struct statfs stfs;
  86 #endif
  87
  88     if (phys_ram_fd < 0) {
  89         tmpdir = getenv("QEMU_TMPDIR");
  90         if (!tmpdir)
  91 #ifdef HOST_SOLARIS
  92             tmpdir = "/tmp";
  93         if (statvfs(tmpdir, &stfs) == 0) {
  94 #else
  95             tmpdir = "/dev/shm";
  96         if (statfs(tmpdir, &stfs) == 0) {
  97 #endif
  98             int64_t free_space;
  99             int ram_mb;
 100
 101             extern int ram_size;
 102             free_space = (int64_t)stfs.f_bavail * stfs.f_bsize;
 103             if ((ram_size + 8192 * 1024) >= free_space) {
 104                 ram_mb = (ram_size / (1024 * 1024));
 105                 fprintf(stderr,
 106                         "You do not have enough space in '%s' for the %d MB of QEMU virtual RAM.\n",
 107                         tmpdir, ram_mb);
 108                 if (strcmp(tmpdir, "/dev/shm") == 0) {
 109                     fprintf(stderr, "To have more space available provided you have enough RAM and swap, do as root:\n"
 110                             "umount /dev/shm\n"
 111                             "mount -t tmpfs -o size=%dm none /dev/shm\n",
 112                             ram_mb + 16);
 113                 } else {
 114                     fprintf(stderr,
 115                             "Use the '-m' option of QEMU to diminish the amount of virtual RAM or use the\n"
 116                             "QEMU_TMPDIR environment variable to set another directory where the QEMU\n"
 117                             "temporary RAM file will be opened.\n");
 118                 }
 119                 fprintf(stderr, "Or disable the accelerator module with -no-kqemu\n");
 120                 exit(1);
 121             }
 122         }
 123         snprintf(phys_ram_file, sizeof(phys_ram_file), "%s/qemuXXXXXX",
 124                  tmpdir);
 125         phys_ram_fd = mkstemp(phys_ram_file);
 126         if (phys_ram_fd < 0) {
 127             fprintf(stderr,
 128                     "warning: could not create temporary file in '%s'.\n"
 129                     "Use QEMU_TMPDIR to select a directory in a tmpfs filesystem.\n"
 130                     "Using '/tmp' as fallback.\n",
 131                     tmpdir);
 132             snprintf(phys_ram_file, sizeof(phys_ram_file), "%s/qemuXXXXXX",
 133                      "/tmp");
 134             phys_ram_fd = mkstemp(phys_ram_file);
 135             if (phys_ram_fd < 0) {
 136                 fprintf(stderr, "Could not create temporary memory file '%s'\n",
 137                         phys_ram_file);
 138                 exit(1);
 139             }
 140         }
 141         unlink(phys_ram_file);
 142     }
 143     size = (size + 4095) & ~4095;
 144     ftruncate(phys_ram_fd, phys_ram_size + size);
 145     ptr = mmap(NULL,
 146                size,
 147                PROT_WRITE | PROT_READ, MAP_SHARED,
 148                phys_ram_fd, phys_ram_size);
 149     if (ptr == MAP_FAILED) {
 150         fprintf(stderr, "Could not map physical memory\n");
 151         exit(1);
 152     }
 153     phys_ram_size += size;
 154     return ptr;
 155 }
 156
 157 static void kqemu_vfree(void *ptr)
 158 {
 159     /* may be useful some day, but currently we do not need to free */
 160 }
 161
 162 #endif
 163
 164 void *qemu_memalign(size_t alignment, size_t size)
 165 {
 166 #if defined(_POSIX_C_SOURCE)
 167     int ret;
 168     void *ptr;
 169     ret = posix_memalign(&ptr, alignment, size);
 170     if (ret != 0)
 171         return NULL;
 172     return ptr;
 173 #elif defined(_BSD)
 174     return valloc(size);
 175 #else
 176     return memalign(alignment, size);
 177 #endif
 178 }
 179
 180 /* alloc shared memory pages */
 181 void *qemu_vmalloc(size_t size)
 182 {
 183 #if defined(USE_KQEMU)
 184     if (kqemu_allowed)
 185         return kqemu_vmalloc(size);
 186 #endif
 187 #ifdef _BSD
 188     return valloc(size);
 189 #else
 190     return memalign(4096, size);
 191 #endif
 192 }
 193
 194 void qemu_vfree(void *ptr)
 195 {
 196 #if defined(USE_KQEMU)
 197     if (kqemu_allowed)
 198         kqemu_vfree(ptr);
 199 #endif
 200     free(ptr);
 201 }
 202
 203 #endif
 204
 205 int qemu_create_pidfile(const char *filename)
 206 {
 207     char buffer[128];
 208     int len;
 209 #ifndef _WIN32
 210     int fd;
 211
 212     fd = open(filename, O_RDWR | O_CREAT, 0600);
 213     if (fd == -1)
 214         return -1;
 215
 216     if (lockf(fd, F_TLOCK, 0) == -1)
 217         return -1;
 218
 219     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 220     if (write(fd, buffer, len) != len)
 221         return -1;
 222 #else
 223     HANDLE file;
 224     DWORD flags;
 225     OVERLAPPED overlap;
 226     BOOL ret;
 227
 228     /* Open for writing with no sharing. */
 229     file = CreateFile(filename, GENERIC_WRITE, 0, NULL,
 230                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 231
 232     if (file == INVALID_HANDLE_VALUE)
 233       return -1;
 234
 235     flags = LOCKFILE_EXCLUSIVE_LOCK | LOCKFILE_FAIL_IMMEDIATELY;
 236     overlap.hEvent = 0;
 237     /* Lock 1 byte. */
 238     ret = LockFileEx(file, flags, 0, 0, 1, &overlap);
 239     if (ret == 0)
 240       return -1;
 241
 242     /* Write PID to file. */
 243     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 244     ret = WriteFileEx(file, (LPCVOID)buffer, (DWORD)len,
 245                       &overlap, NULL);
 246     if (ret == 0)
 247       return -1;
 248 #endif
 249     return 0;
 250 }
 251
 252 #ifdef _WIN32
 253
 254 /* Offset between 1/1/1601 and 1/1/1970 in 100 nanosec units */
 255 #define _W32_FT_OFFSET (116444736000000000ULL)
 256
 257 int qemu_gettimeofday(qemu_timeval *tp)
 258 {
 259   union {
 260     unsigned long long ns100; /*time since 1 Jan 1601 in 100ns units */
 261     FILETIME ft;
 262   }  _now;
 263
 264   if(tp)
 265     {
 266       GetSystemTimeAsFileTime (&_now.ft);
 267       tp->tv_usec=(long)((_now.ns100 / 10ULL) % 1000000ULL );
 268       tp->tv_sec= (long)((_now.ns100 - _W32_FT_OFFSET) / 10000000ULL);
 269     }
 270   /* Always return 0 as per Open Group Base Specifications Issue 6.
 271      Do not set errno on error.  */
 272   return 0;
 273 }
 274 #endif /* _WIN32 */