+void qemu_flush_coalesced_mmio_buffer(void)
+{
+ if (kvm_enabled())
+ kvm_flush_coalesced_mmio_buffer();
+}
+
+#if defined(__linux__) && !defined(TARGET_S390X)
+
+#include <sys/vfs.h>
+
+#define HUGETLBFS_MAGIC 0x958458f6
+
+static long gethugepagesize(const char *path)
+{
+ struct statfs fs;
+ int ret;
+
+ do {
+ ret = statfs(path, &fs);
+ } while (ret != 0 && errno == EINTR);
+
+ if (ret != 0) {
+ perror(path);
+ return 0;
+ }
+
+ if (fs.f_type != HUGETLBFS_MAGIC)
+ fprintf(stderr, "Warning: path not on HugeTLBFS: %s\n", path);
+
+ return fs.f_bsize;
+}
+
+static void *file_ram_alloc(RAMBlock *block,
+ ram_addr_t memory,
+ const char *path)
+{
+ char *filename;
+ void *area;
+ int fd;
+#ifdef MAP_POPULATE
+ int flags;
+#endif
+ unsigned long hpagesize;
+
+ hpagesize = gethugepagesize(path);
+ if (!hpagesize) {
+ return NULL;
+ }
+
+ if (memory < hpagesize) {
+ return NULL;
+ }
+
+ if (kvm_enabled() && !kvm_has_sync_mmu()) {
+ fprintf(stderr, "host lacks kvm mmu notifiers, -mem-path unsupported\n");
+ return NULL;
+ }
+
+ if (asprintf(&filename, "%s/qemu_back_mem.XXXXXX", path) == -1) {
+ return NULL;
+ }
+
+ fd = mkstemp(filename);
+ if (fd < 0) {
+ perror("unable to create backing store for hugepages");
+ free(filename);
+ return NULL;
+ }
+ unlink(filename);
+ free(filename);
+
+ memory = (memory+hpagesize-1) & ~(hpagesize-1);
+
+ /*
+ * ftruncate is not supported by hugetlbfs in older
+ * hosts, so don't bother bailing out on errors.
+ * If anything goes wrong with it under other filesystems,
+ * mmap will fail.
+ */
+ if (ftruncate(fd, memory))
+ perror("ftruncate");
+
+#ifdef MAP_POPULATE
+ /* NB: MAP_POPULATE won't exhaustively alloc all phys pages in the case
+ * MAP_PRIVATE is requested. For mem_prealloc we mmap as MAP_SHARED
+ * to sidestep this quirk.
+ */
+ flags = mem_prealloc ? MAP_POPULATE | MAP_SHARED : MAP_PRIVATE;
+ area = mmap(0, memory, PROT_READ | PROT_WRITE, flags, fd, 0);
+#else
+ area = mmap(0, memory, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+#endif
+ if (area == MAP_FAILED) {
+ perror("file_ram_alloc: can't mmap RAM pages");
+ close(fd);
+ return (NULL);
+ }
+ block->fd = fd;
+ return area;
+}
+#endif
+
+static ram_addr_t find_ram_offset(ram_addr_t size)
+{
+ RAMBlock *block, *next_block;
+ ram_addr_t offset = 0, mingap = ULONG_MAX;
+
+ if (QLIST_EMPTY(&ram_list.blocks))
+ return 0;
+
+ QLIST_FOREACH(block, &ram_list.blocks, next) {
+ ram_addr_t end, next = ULONG_MAX;
+
+ end = block->offset + block->length;
+
+ QLIST_FOREACH(next_block, &ram_list.blocks, next) {
+ if (next_block->offset >= end) {
+ next = MIN(next, next_block->offset);
+ }
+ }
+ if (next - end >= size && next - end < mingap) {
+ offset = end;
+ mingap = next - end;
+ }
+ }
+ return offset;
+}
+
+static ram_addr_t last_ram_offset(void)
+{
+ RAMBlock *block;
+ ram_addr_t last = 0;
+
+ QLIST_FOREACH(block, &ram_list.blocks, next)
+ last = MAX(last, block->offset + block->length);
+
+ return last;
projects / qemu.git / blobdiff