static int kvm_physical_sync_dirty_bitmap(MemoryRegionSection *section) { KVMState *s = kvm_state; unsigned long size, allocated_size = 0; KVMDirtyLog d; KVMSlot *mem; int ret = 0; hwaddr start_addr = section->offset_within_address_space; hwaddr end_addr = start_addr + int128_get64(section->size); d.dirty_bitmap = NULL; while (start_addr < end_addr) { mem = kvm_lookup_overlapping_slot(s, start_addr, end_addr); if (mem == NULL) { break; } /* XXX bad kernel interface alert * For dirty bitmap, kernel allocates array of size aligned to * bits-per-long. But for case when the kernel is 64bits and * the userspace is 32bits, userspace can't align to the same * bits-per-long, since sizeof(long) is different between kernel * and user space. This way, userspace will provide buffer which * may be 4 bytes less than the kernel will use, resulting in * userspace memory corruption (which is not detectable by valgrind * too, in most cases). * So for now, let's align to 64 instead of HOST_LONG_BITS here, in * a hope that sizeof(long) wont become >8 any time soon. */ size = ALIGN(((mem->memory_size) >> TARGET_PAGE_BITS), /*HOST_LONG_BITS*/ 64) / 8; if (!d.dirty_bitmap) { d.dirty_bitmap = g_malloc(size); } else if (size > allocated_size) { d.dirty_bitmap = g_realloc(d.dirty_bitmap, size); } allocated_size = size; memset(d.dirty_bitmap, 0, allocated_size); d.slot = mem->slot; if (kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d) == -1) { DPRINTF("ioctl failed %d\n", errno); ret = -1; break; } kvm_get_dirty_pages_log_range(section, d.dirty_bitmap); start_addr = mem->start_addr + mem->memory_size; } g_free(d.dirty_bitmap); return ret; }
static int kvm_physical_sync_dirty_bitmap(MemoryRegionSection *section) { KVMState *s = kvm_state; unsigned long size, allocated_size = 0; KVMDirtyLog d; KVMSlot *mem; int ret = 0; hwaddr start_addr = section->offset_within_address_space; hwaddr end_addr = start_addr + int128_get64(section->size); d.dirty_bitmap = NULL; while (start_addr < end_addr) { mem = kvm_lookup_overlapping_slot(s, start_addr, end_addr); if (mem == NULL) { break; }   size = ALIGN(((mem->memory_size) >> TARGET_PAGE_BITS),   64) / 8; if (!d.dirty_bitmap) { d.dirty_bitmap = g_malloc(size); } else if (size > allocated_size) { d.dirty_bitmap = g_realloc(d.dirty_bitmap, size); } allocated_size = size; memset(d.dirty_bitmap, 0, allocated_size); d.slot = mem->slot; if (kvm_vm_ioctl(s, KVM_GET_DIRTY_LOG, &d) == -1) { DPRINTF("ioctl failed %d\n", errno); ret = -1; break; } kvm_get_dirty_pages_log_range(section, d.dirty_bitmap); start_addr = mem->start_addr + mem->memory_size; } g_free(d.dirty_bitmap); return ret; }