+#if defined(_WIN32)
+
+void *qemu_vmalloc(size_t size)
+{
+ /* FIXME: this is not exactly optimal solution since VirtualAlloc
+ has 64Kb granularity, but at least it guarantees us that the
+ memory is page aligned. */
+ return VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
+}
+
+void qemu_vfree(void *ptr)
+{
+ VirtualFree(ptr, 0, MEM_RELEASE);
+}
+
+#elif defined(USE_KQEMU)
+
+#include <sys/vfs.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+
+void *qemu_vmalloc(size_t size)
+{
+ static int phys_ram_fd = -1;
+ static int phys_ram_size = 0;
+ const char *tmpdir;
+ char phys_ram_file[1024];
+ void *ptr;
+ struct statfs stfs;
+
+ if (phys_ram_fd < 0) {
+ tmpdir = getenv("QEMU_TMPDIR");
+ if (!tmpdir)
+ tmpdir = "/dev/shm";
+ if (statfs(tmpdir, &stfs) == 0) {
+ int64_t free_space;
+ int ram_mb;
+
+ extern int ram_size;
+ free_space = (int64_t)stfs.f_bavail * stfs.f_bsize;
+ if ((ram_size + 8192 * 1024) >= free_space) {
+ ram_mb = (ram_size / (1024 * 1024));
+ fprintf(stderr,
+ "You do not have enough space in '%s' for the %d MB of QEMU virtual RAM.\n",
+ tmpdir, ram_mb);
+ if (strcmp(tmpdir, "/dev/shm") == 0) {
+ fprintf(stderr, "To have more space available provided you have enough RAM and swap, do as root:\n"
+ "umount /dev/shm\n"
+ "mount -t tmpfs -o size=%dm none /dev/shm\n",
+ ram_mb + 16);
+ } else {
+ fprintf(stderr,
+ "Use the '-m' option of QEMU to diminish the amount of virtual RAM or use the\n"
+ "QEMU_TMPDIR environment variable to set another directory where the QEMU\n"
+ "temporary RAM file will be opened.\n");
+ }
+ exit(1);
+ }
+ }
+ snprintf(phys_ram_file, sizeof(phys_ram_file), "%s/qemuXXXXXX",
+ tmpdir);
+ if (mkstemp(phys_ram_file) < 0) {
+ fprintf(stderr,
+ "warning: could not create temporary file in '%s'.\n"
+ "Use QEMU_TMPDIR to select a directory in a tmpfs filesystem.\n"
+ "Using '/tmp' as fallback.\n",
+ tmpdir);
+ snprintf(phys_ram_file, sizeof(phys_ram_file), "%s/qemuXXXXXX",
+ "/tmp");
+ if (mkstemp(phys_ram_file) < 0) {
+ fprintf(stderr, "Could not create temporary memory file '%s'\n",
+ phys_ram_file);
+ exit(1);
+ }
+ }
+ phys_ram_fd = open(phys_ram_file, O_CREAT | O_TRUNC | O_RDWR, 0600);
+ if (phys_ram_fd < 0) {
+ fprintf(stderr, "Could not open temporary memory file '%s'\n",
+ phys_ram_file);
+ exit(1);
+ }
+ unlink(phys_ram_file);
+ }
+ size = (size + 4095) & ~4095;
+ ftruncate(phys_ram_fd, phys_ram_size + size);
+ ptr = mmap(NULL,
+ size,
+ PROT_WRITE | PROT_READ, MAP_SHARED,
+ phys_ram_fd, phys_ram_size);
+ if (ptr == MAP_FAILED) {
+ fprintf(stderr, "Could not map physical memory\n");
+ exit(1);
+ }
+ phys_ram_size += size;
+ return ptr;
+}
+
+void qemu_vfree(void *ptr)
+{
+ /* may be useful some day, but currently we do not need to free */
+}
+
+#else
+
+/* alloc shared memory pages */
+void *qemu_vmalloc(size_t size)
+{
+#ifdef _BSD
+ return valloc(size);
+#else
+ return memalign(4096, size);
+#endif
+}
+
+void qemu_vfree(void *ptr)
+{
+ free(ptr);
+}
+
+#endif
+