+int kvm_check_extension(KVMState *s, unsigned int extension)
+{
+ int ret;
+
+ ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, extension);
+ if (ret < 0) {
+ ret = 0;
+ }
+
+ return ret;
+}
+
+static void kvm_set_phys_mem(target_phys_addr_t start_addr,
+ ram_addr_t size,
+ ram_addr_t phys_offset)
+{
+ KVMState *s = kvm_state;
+ ram_addr_t flags = phys_offset & ~TARGET_PAGE_MASK;
+ KVMSlot *mem, old;
+ int err;
+
+ if (start_addr & ~TARGET_PAGE_MASK) {
+ if (flags >= IO_MEM_UNASSIGNED) {
+ if (!kvm_lookup_overlapping_slot(s, start_addr,
+ start_addr + size)) {
+ return;
+ }
+ fprintf(stderr, "Unaligned split of a KVM memory slot\n");
+ } else {
+ fprintf(stderr, "Only page-aligned memory slots supported\n");
+ }
+ abort();
+ }
+
+ /* KVM does not support read-only slots */
+ phys_offset &= ~IO_MEM_ROM;
+
+ while (1) {
+ mem = kvm_lookup_overlapping_slot(s, start_addr, start_addr + size);
+ if (!mem) {
+ break;
+ }
+
+ if (flags < IO_MEM_UNASSIGNED && start_addr >= mem->start_addr &&
+ (start_addr + size <= mem->start_addr + mem->memory_size) &&
+ (phys_offset - start_addr == mem->phys_offset - mem->start_addr)) {
+ /* The new slot fits into the existing one and comes with
+ * identical parameters - nothing to be done. */
+ return;
+ }
+
+ old = *mem;
+
+ /* unregister the overlapping slot */
+ mem->memory_size = 0;
+ err = kvm_set_user_memory_region(s, mem);
+ if (err) {
+ fprintf(stderr, "%s: error unregistering overlapping slot: %s\n",
+ __func__, strerror(-err));
+ abort();
+ }
+
+ /* Workaround for older KVM versions: we can't join slots, even not by
+ * unregistering the previous ones and then registering the larger
+ * slot. We have to maintain the existing fragmentation. Sigh.
+ *
+ * This workaround assumes that the new slot starts at the same
+ * address as the first existing one. If not or if some overlapping
+ * slot comes around later, we will fail (not seen in practice so far)
+ * - and actually require a recent KVM version. */
+ if (s->broken_set_mem_region &&
+ old.start_addr == start_addr && old.memory_size < size &&
+ flags < IO_MEM_UNASSIGNED) {
+ mem = kvm_alloc_slot(s);
+ mem->memory_size = old.memory_size;
+ mem->start_addr = old.start_addr;
+ mem->phys_offset = old.phys_offset;
+ mem->flags = 0;
+
+ err = kvm_set_user_memory_region(s, mem);
+ if (err) {
+ fprintf(stderr, "%s: error updating slot: %s\n", __func__,
+ strerror(-err));
+ abort();
+ }
+
+ start_addr += old.memory_size;
+ phys_offset += old.memory_size;
+ size -= old.memory_size;
+ continue;
+ }
+
+ /* register prefix slot */
+ if (old.start_addr < start_addr) {
+ mem = kvm_alloc_slot(s);
+ mem->memory_size = start_addr - old.start_addr;
+ mem->start_addr = old.start_addr;
+ mem->phys_offset = old.phys_offset;
+ mem->flags = 0;
+
+ err = kvm_set_user_memory_region(s, mem);
+ if (err) {
+ fprintf(stderr, "%s: error registering prefix slot: %s\n",
+ __func__, strerror(-err));
+ abort();
+ }
+ }
+
+ /* register suffix slot */
+ if (old.start_addr + old.memory_size > start_addr + size) {
+ ram_addr_t size_delta;
+
+ mem = kvm_alloc_slot(s);
+ mem->start_addr = start_addr + size;
+ size_delta = mem->start_addr - old.start_addr;
+ mem->memory_size = old.memory_size - size_delta;
+ mem->phys_offset = old.phys_offset + size_delta;
+ mem->flags = 0;
+
+ err = kvm_set_user_memory_region(s, mem);
+ if (err) {
+ fprintf(stderr, "%s: error registering suffix slot: %s\n",
+ __func__, strerror(-err));
+ abort();
+ }
+ }
+ }
+
+ /* in case the KVM bug workaround already "consumed" the new slot */
+ if (!size)
+ return;
+
+ /* KVM does not need to know about this memory */
+ if (flags >= IO_MEM_UNASSIGNED)
+ return;
+
+ mem = kvm_alloc_slot(s);
+ mem->memory_size = size;
+ mem->start_addr = start_addr;
+ mem->phys_offset = phys_offset;
+ mem->flags = 0;
+
+ err = kvm_set_user_memory_region(s, mem);
+ if (err) {
+ fprintf(stderr, "%s: error registering slot: %s\n", __func__,
+ strerror(-err));
+ abort();
+ }
+}
+
+static void kvm_client_set_memory(struct CPUPhysMemoryClient *client,
+ target_phys_addr_t start_addr,
+ ram_addr_t size,
+ ram_addr_t phys_offset)
+{
+ kvm_set_phys_mem(start_addr, size, phys_offset);
+}
+
+static int kvm_client_sync_dirty_bitmap(struct CPUPhysMemoryClient *client,
+ target_phys_addr_t start_addr,
+ target_phys_addr_t end_addr)
+{
+ return kvm_physical_sync_dirty_bitmap(start_addr, end_addr);
+}
+
+static int kvm_client_migration_log(struct CPUPhysMemoryClient *client,
+ int enable)
+{
+ return kvm_set_migration_log(enable);
+}
+
+static CPUPhysMemoryClient kvm_cpu_phys_memory_client = {
+ .set_memory = kvm_client_set_memory,
+ .sync_dirty_bitmap = kvm_client_sync_dirty_bitmap,
+ .migration_log = kvm_client_migration_log,
+};
+