#include <palacios/vmm_dev_mgr.h>
+#ifdef V3_CONFIG_LIVE_MIGRATION
+#include <palacios/vmm_time.h>
+#include <palacios/vm_guest_mem.h>
+#include <palacios/vmm_shadow_paging.h>
+#endif
+
+#ifndef V3_CONFIG_DEBUG_CHECKPOINT
+#undef PrintDebug
+#define PrintDebug(fmt, args...)
+#endif
+
static struct hashtable * store_table = NULL;
return 0;
}
+#ifdef V3_CONFIG_LIVE_MIGRATION
+
+struct mem_migration_state {
+ struct v3_vm_info *vm;
+ struct v3_bitmap modified_pages;
+};
+
+static int paging_callback(struct guest_info *core,
+ struct v3_shdw_pg_event *event,
+ void *priv_data)
+{
+ struct mem_migration_state *m = (struct mem_migration_state *)priv_data;
+
+ if (event->event_type==SHADOW_PAGEFAULT &&
+ event->event_order==SHADOW_PREIMPL &&
+ event->error_code.write) {
+ addr_t gpa;
+ if (!v3_gva_to_gpa(core,event->gva,&gpa)) {
+ // write to this page
+ v3_bitmap_set(&(m->modified_pages),gpa>>12);
+ } else {
+ // no worries, this isn't physical memory
+ }
+ } else {
+ // we don't care about other events
+ }
+
+ return 0;
+}
+
+
+
+static struct mem_migration_state *start_page_tracking(struct v3_vm_info *vm)
+{
+ struct mem_migration_state *m;
+ int i;
+
+ m = (struct mem_migration_state *)V3_Malloc(sizeof(struct mem_migration_state));
+
+ if (!m) {
+ PrintError("Cannot allocate\n");
+ return NULL;
+ }
+
+ m->vm=vm;
+
+ if (v3_bitmap_init(&(m->modified_pages),vm->mem_size >> 12) == -1) {
+ PrintError("Failed to initialize modified_pages bit vector");
+ V3_Free(m);
+ }
+
+ v3_register_shadow_paging_event_callback(vm,paging_callback,m);
+
+ for (i=0;i<vm->num_cores;i++) {
+ v3_invalidate_shadow_pts(&(vm->cores[i]));
+ }
+
+ // and now we should get callbacks as writes happen
+
+ return m;
+}
+
+static void stop_page_tracking(struct mem_migration_state *m)
+{
+ v3_unregister_shadow_paging_event_callback(m->vm,paging_callback,m);
+
+ v3_bitmap_deinit(&(m->modified_pages));
+
+ V3_Free(m);
+}
+
+
+
+
+
+
+//
+// Returns
+// negative: error
+// zero: done with this round
+static int save_inc_memory(struct v3_vm_info * vm,
+ struct v3_bitmap * mod_pgs_to_send,
+ struct v3_chkpt * chkpt) {
+ int page_size_bytes = 1 << 12; // assuming 4k pages right now
+ void * ctx = NULL;
+ int i = 0;
+ void * guest_mem_base = NULL;
+ int bitmap_num_bytes = (mod_pgs_to_send->num_bits / 8)
+ + ((mod_pgs_to_send->num_bits % 8) > 0);
+
+
+ guest_mem_base = V3_VAddr((void *)vm->mem_map.base_region.host_addr);
+
+ PrintDebug("Saving incremental memory.\n");
+
+ ctx = v3_chkpt_open_ctx(chkpt, NULL,"memory_bitmap_bits");
+
+ if (!ctx) {
+ PrintError("Cannot open context for dirty memory bitmap\n");
+ return -1;
+ }
+
+
+ if (v3_chkpt_save(ctx,
+ "memory_bitmap_bits",
+ bitmap_num_bytes,
+ mod_pgs_to_send->bits) == -1) {
+ PrintError("Unable to write all of the dirty memory bitmap\n");
+ v3_chkpt_close_ctx(ctx);
+ return -1;
+ }
+
+ v3_chkpt_close_ctx(ctx);
+
+ PrintDebug("Sent bitmap bits.\n");
+
+ // Dirty memory pages are sent in bitmap order
+ for (i = 0; i < mod_pgs_to_send->num_bits; i++) {
+ if (v3_bitmap_check(mod_pgs_to_send, i)) {
+ // PrintDebug("Sending memory page %d.\n",i);
+ ctx = v3_chkpt_open_ctx(chkpt, NULL,"memory_page");
+ if (!ctx) {
+ PrintError("Unable to open context to send memory page\n");
+ return -1;
+ }
+ if (v3_chkpt_save(ctx,
+ "memory_page",
+ page_size_bytes,
+ guest_mem_base + (page_size_bytes * i)) == -1) {
+ PrintError("Unable to send a memory page\n");
+ v3_chkpt_close_ctx(ctx);
+ return -1;
+ }
+
+ v3_chkpt_close_ctx(ctx);
+ }
+ }
+
+ return 0;
+}
+
+
+//
+// returns:
+// negative: error
+// zero: ok, but not done
+// positive: ok, and also done
+static int load_inc_memory(struct v3_vm_info * vm,
+ struct v3_bitmap * mod_pgs,
+ struct v3_chkpt * chkpt) {
+ int page_size_bytes = 1 << 12; // assuming 4k pages right now
+ void * ctx = NULL;
+ int i = 0;
+ void * guest_mem_base = NULL;
+ bool empty_bitmap = true;
+ int bitmap_num_bytes = (mod_pgs->num_bits / 8)
+ + ((mod_pgs->num_bits % 8) > 0);
+
+
+ guest_mem_base = V3_VAddr((void *)vm->mem_map.base_region.host_addr);
+
+ ctx = v3_chkpt_open_ctx(chkpt, NULL,"memory_bitmap_bits");
+
+ if (!ctx) {
+ PrintError("Cannot open context to receive memory bitmap\n");
+ return -1;
+ }
+
+ if (v3_chkpt_load(ctx,
+ "memory_bitmap_bits",
+ bitmap_num_bytes,
+ mod_pgs->bits) == -1) {
+ PrintError("Did not receive all of memory bitmap\n");
+ v3_chkpt_close_ctx(ctx);
+ return -1;
+ }
+
+ v3_chkpt_close_ctx(ctx);
+
+ // Receive also follows bitmap order
+ for (i = 0; i < mod_pgs->num_bits; i ++) {
+ if (v3_bitmap_check(mod_pgs, i)) {
+ PrintDebug("Loading page %d\n", i);
+ empty_bitmap = false;
+ ctx = v3_chkpt_open_ctx(chkpt, NULL,"memory_page");
+ if (!ctx) {
+ PrintError("Cannot open context to receive memory page\n");
+ return -1;
+ }
+
+ if (v3_chkpt_load(ctx,
+ "memory_page",
+ page_size_bytes,
+ guest_mem_base + (page_size_bytes * i)) == -1) {
+ PrintError("Did not receive all of memory page\n");
+ v3_chkpt_close_ctx(ctx);
+ return -1;
+ }
+ v3_chkpt_close_ctx(ctx);
+ }
+ }
+
+ if (empty_bitmap) {
+ // signal end of receiving pages
+ PrintDebug("Finished receiving pages.\n");
+ return 1;
+ } else {
+ // need to run again
+ return 0;
+ }
+
+}
+
+#endif
+
int save_header(struct v3_vm_info * vm, struct v3_chkpt * chkpt) {
extern v3_cpu_arch_t v3_mach_type;
void * ctx = NULL;
struct v3_chkpt * chkpt = NULL;
int ret = 0;;
int i = 0;
-
+
+
chkpt = chkpt_open(vm, store, url, SAVE);
if (chkpt == NULL) {
chkpt_close(chkpt);
return ret;
+
+}
+
+
+#ifdef V3_CONFIG_LIVE_MIGRATION
+
+#define MOD_THRESHOLD 200 // pages below which we declare victory
+#define ITER_THRESHOLD 32 // iters below which we declare victory
+
+
+
+int v3_chkpt_send_vm(struct v3_vm_info * vm, char * store, char * url) {
+ struct v3_chkpt * chkpt = NULL;
+ int ret = 0;;
+ int iter = 0;
+ bool last_modpage_iteration=false;
+ struct v3_bitmap modified_pages_to_send;
+ uint64_t start_time;
+ uint64_t stop_time;
+ int num_mod_pages=0;
+ struct mem_migration_state *mm_state;
+ int i;
+
+ // Currently will work only for shadow paging
+ for (i=0;i<vm->num_cores;i++) {
+ if (vm->cores[i].shdw_pg_mode!=SHADOW_PAGING) {
+ PrintError("Cannot currently handle nested paging\n");
+ return -1;
+ }
+ }
+
+
+ chkpt = chkpt_open(vm, store, url, SAVE);
+
+ if (chkpt == NULL) {
+ PrintError("Error creating checkpoint store\n");
+ chkpt_close(chkpt);
+ return -1;
+ }
+
+ // In a send, the memory is copied incrementally first,
+ // followed by the remainder of the state
+
+ if (v3_bitmap_init(&modified_pages_to_send,
+ vm->mem_size>>12 // number of pages in main region
+ ) == -1) {
+ PrintError("Could not intialize bitmap.\n");
+ return -1;
+ }
+
+ // 0. Initialize bitmap to all 1s
+ for (i=0; i < modified_pages_to_send.num_bits; i++) {
+ v3_bitmap_set(&modified_pages_to_send,i);
+ }
+
+ iter = 0;
+ while (!last_modpage_iteration) {
+ PrintDebug("Modified memory page iteration %d\n",i++);
+
+ start_time = v3_get_host_time(&(vm->cores[0].time_state));
+
+ // We will pause the VM for a short while
+ // so that we can collect the set of changed pages
+ if (v3_pause_vm(vm) == -1) {
+ PrintError("Could not pause VM\n");
+ ret = -1;
+ goto out;
+ }
+
+ if (iter==0) {
+ // special case, we already have the pages to send (all of them)
+ // they are already in modified_pages_to_send
+ } else {
+ // normally, we are in the middle of a round
+ // We need to copy from the current tracking bitmap
+ // to our send bitmap
+ v3_bitmap_copy(&modified_pages_to_send,&(mm_state->modified_pages));
+ // and now we need to remove our tracking
+ stop_page_tracking(mm_state);
+ }
+
+ // are we done? (note that we are still paused)
+ num_mod_pages = v3_bitmap_count(&modified_pages_to_send);
+ if (num_mod_pages<MOD_THRESHOLD || iter>ITER_THRESHOLD) {
+ // we are done, so we will not restart page tracking
+ // the vm is paused, and so we should be able
+ // to just send the data
+ PrintDebug("Last modified memory page iteration.\n");
+ last_modpage_iteration = true;
+ } else {
+ // we are not done, so we will restart page tracking
+ // to prepare for a second round of pages
+ // we will resume the VM as this happens
+ if (!(mm_state=start_page_tracking(vm))) {
+ PrintError("Error enabling page tracking.\n");
+ ret = -1;
+ goto out;
+ }
+ if (v3_continue_vm(vm) == -1) {
+ PrintError("Error resuming the VM\n");
+ stop_page_tracking(mm_state);
+ ret = -1;
+ goto out;
+ }
+
+ stop_time = v3_get_host_time(&(vm->cores[0].time_state));
+ PrintDebug("num_mod_pages=%d\ndowntime=%llu\n",num_mod_pages,stop_time-start_time);
+ }
+
+
+ // At this point, we are either paused and about to copy
+ // the last chunk, or we are running, and will copy the last
+ // round in parallel with current execution
+ if (num_mod_pages>0) {
+ if (save_inc_memory(vm, &modified_pages_to_send, chkpt) == -1) {
+ PrintError("Error sending incremental memory.\n");
+ ret = -1;
+ goto out;
+ }
+ } // we don't want to copy an empty bitmap here
+
+ iter++;
+ }
+
+ if (v3_bitmap_reset(&modified_pages_to_send) == -1) {
+ PrintError("Error reseting bitmap.\n");
+ ret = -1;
+ goto out;
+ }
+
+ // send bitmap of 0s to signal end of modpages
+ if (save_inc_memory(vm, &modified_pages_to_send, chkpt) == -1) {
+ PrintError("Error sending incremental memory.\n");
+ ret = -1;
+ goto out;
+ }
+
+ // save the non-memory state
+ if ((ret = v3_save_vm_devices(vm, chkpt)) == -1) {
+ PrintError("Unable to save devices\n");
+ goto out;
+ }
+
+
+ if ((ret = save_header(vm, chkpt)) == -1) {
+ PrintError("Unable to save header\n");
+ goto out;
+ }
+
+ for (i = 0; i < vm->num_cores; i++){
+ if ((ret = save_core(&(vm->cores[i]), chkpt)) == -1) {
+ PrintError("chkpt of core %d failed\n", i);
+ goto out;
+ }
+ }
+
+ stop_time = v3_get_host_time(&(vm->cores[0].time_state));
+ PrintDebug("num_mod_pages=%d\ndowntime=%llu\n",num_mod_pages,stop_time-start_time);
+ PrintDebug("Done sending VM!\n");
+ out:
+ v3_bitmap_deinit(&modified_pages_to_send);
+ chkpt_close(chkpt);
+
+ return ret;
+
}
+int v3_chkpt_receive_vm(struct v3_vm_info * vm, char * store, char * url) {
+ struct v3_chkpt * chkpt = NULL;
+ int i = 0;
+ int ret = 0;
+ struct v3_bitmap mod_pgs;
+
+ // Currently will work only for shadow paging
+ for (i=0;i<vm->num_cores;i++) {
+ if (vm->cores[i].shdw_pg_mode!=SHADOW_PAGING) {
+ PrintError("Cannot currently handle nested paging\n");
+ return -1;
+ }
+ }
+
+ chkpt = chkpt_open(vm, store, url, LOAD);
+
+ if (chkpt == NULL) {
+ PrintError("Error creating checkpoint store\n");
+ chkpt_close(chkpt);
+ return -1;
+ }
+
+ if (v3_bitmap_init(&mod_pgs,vm->mem_size>>12) == -1) {
+ chkpt_close(chkpt);
+ PrintError("Could not intialize bitmap.\n");
+ return -1;
+ }
+
+ /* If this guest is running we need to block it while the checkpoint occurs */
+ if (vm->run_state == VM_RUNNING) {
+ while (v3_raise_barrier(vm, NULL) == -1);
+ }
+
+ i = 0;
+ while(true) {
+ // 1. Receive copy of bitmap
+ // 2. Receive pages
+ PrintDebug("Memory page iteration %d\n",i++);
+ int retval = load_inc_memory(vm, &mod_pgs, chkpt);
+ if (retval == 1) {
+ // end of receiving memory pages
+ break;
+ } else if (retval == -1) {
+ PrintError("Error receiving incremental memory.\n");
+ ret = -1;
+ goto out;
+ }
+ }
+
+ if ((ret = v3_load_vm_devices(vm, chkpt)) == -1) {
+ PrintError("Unable to load devices\n");
+ ret = -1;
+ goto out;
+ }
+
+
+ if ((ret = load_header(vm, chkpt)) == -1) {
+ PrintError("Unable to load header\n");
+ ret = -1;
+ goto out;
+ }
+
+ //per core cloning
+ for (i = 0; i < vm->num_cores; i++) {
+ if ((ret = load_core(&(vm->cores[i]), chkpt)) == -1) {
+ PrintError("Error loading core state (core=%d)\n", i);
+ goto out;
+ }
+ }
+
+ out:
+ if (ret==-1) {
+ PrintError("Unable to receive VM\n");
+ } else {
+ PrintDebug("Done receving the VM\n");
+ }
+
+
+ /* Resume the guest if it was running and we didn't just trash the state*/
+ if (vm->run_state == VM_RUNNING) {
+ if (ret == -1) {
+ PrintError("VM was previously running. It is now borked. Pausing it. \n");
+ vm->run_state = VM_STOPPED;
+ }
+
+ /* We check the run state of the VM after every barrier
+ So this will immediately halt the VM
+ */
+ v3_lower_barrier(vm);
+ }
+
+ v3_bitmap_deinit(&mod_pgs);
+ chkpt_close(chkpt);
+ return ret;
+}
+#endif
