/*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2016 Flavius Anton * Copyright (c) 2016 Mihai Tiganus * Copyright (c) 2016-2019 Mihai Carabas * Copyright (c) 2017-2019 Darius Mihai * Copyright (c) 2017-2019 Elena Mihailescu * Copyright (c) 2018-2019 Sergiu Weisz * All rights reserved. * The bhyve-snapshot feature was developed under sponsorships * from Matthew Grooms. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #ifndef WITHOUT_CAPSICUM #include #endif #include #include #include #include #include #include #include #ifndef WITHOUT_CAPSICUM #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef WITHOUT_CAPSICUM #include #endif #include #include #include "bhyverun.h" #include "acpi.h" #include "atkbdc.h" #include "debug.h" #include "inout.h" #include "ipc.h" #include "fwctl.h" #include "ioapic.h" #include "mem.h" #include "mevent.h" #include "mptbl.h" #include "pci_emul.h" #include "pci_irq.h" #include "pci_lpc.h" #include "smbiostbl.h" #include "snapshot.h" #include "xmsr.h" #include "spinup_ap.h" #include "rtc.h" #include #include struct spinner_info { const size_t *crtval; const size_t maxval; const size_t total; }; extern int guest_ncpus; static struct winsize winsize; static sig_t old_winch_handler; #define KB (1024UL) #define MB (1024UL * KB) #define GB (1024UL * MB) #define SNAPSHOT_CHUNK (4 * MB) #define PROG_BUF_SZ (8192) #define SNAPSHOT_BUFFER_SIZE (20 * MB) #define JSON_STRUCT_ARR_KEY "structs" #define JSON_DEV_ARR_KEY "devices" #define JSON_BASIC_METADATA_KEY "basic metadata" #define JSON_SNAPSHOT_REQ_KEY "snapshot_req" #define JSON_SIZE_KEY "size" #define JSON_FILE_OFFSET_KEY "file_offset" #define JSON_NCPUS_KEY "ncpus" #define JSON_VMNAME_KEY "vmname" #define JSON_MEMSIZE_KEY "memsize" #define JSON_MEMFLAGS_KEY "memflags" #define min(a,b) \ ({ \ __typeof__ (a) _a = (a); \ __typeof__ (b) _b = (b); \ _a < _b ? _a : _b; \ }) static const struct vm_snapshot_dev_info snapshot_devs[] = { { "atkbdc", atkbdc_snapshot, NULL, NULL }, { "virtio-net", pci_snapshot, pci_pause, pci_resume }, { "virtio-blk", pci_snapshot, pci_pause, pci_resume }, { "virtio-rnd", pci_snapshot, NULL, NULL }, { "lpc", pci_snapshot, NULL, NULL }, { "fbuf", pci_snapshot, NULL, NULL }, { "xhci", pci_snapshot, NULL, NULL }, { "e1000", pci_snapshot, NULL, NULL }, { "ahci", pci_snapshot, pci_pause, pci_resume }, { "ahci-hd", pci_snapshot, pci_pause, pci_resume }, { "ahci-cd", pci_snapshot, pci_pause, pci_resume }, }; static const struct vm_snapshot_kern_info snapshot_kern_structs[] = { { "vhpet", STRUCT_VHPET }, { "vm", STRUCT_VM }, { "vioapic", STRUCT_VIOAPIC }, { "vlapic", STRUCT_VLAPIC }, { "vmcx", STRUCT_VMCX }, { "vatpit", STRUCT_VATPIT }, { "vatpic", STRUCT_VATPIC }, { "vpmtmr", STRUCT_VPMTMR }, { "vrtc", STRUCT_VRTC }, }; static cpuset_t vcpus_active, vcpus_suspended; static pthread_mutex_t vcpu_lock; static pthread_cond_t vcpus_idle, vcpus_can_run; static bool checkpoint_active; /* * TODO: Harden this function and all of its callers since 'base_str' is a user * provided string. */ static char * strcat_extension(const char *base_str, const char *ext) { char *res; size_t base_len, ext_len; base_len = strnlen(base_str, NAME_MAX); ext_len = strnlen(ext, NAME_MAX); if (base_len + ext_len > NAME_MAX) { fprintf(stderr, "Filename exceeds maximum length.\n"); return (NULL); } res = malloc(base_len + ext_len + 1); if (res == NULL) { perror("Failed to allocate memory."); return (NULL); } memcpy(res, base_str, base_len); memcpy(res + base_len, ext, ext_len); res[base_len + ext_len] = 0; return (res); } void destroy_restore_state(struct restore_state *rstate) { if (rstate == NULL) { fprintf(stderr, "Attempting to destroy NULL restore struct.\n"); return; } if (rstate->kdata_map != MAP_FAILED) munmap(rstate->kdata_map, rstate->kdata_len); if (rstate->kdata_fd > 0) close(rstate->kdata_fd); if (rstate->vmmem_fd > 0) close(rstate->vmmem_fd); if (rstate->meta_root_obj != NULL) ucl_object_unref(rstate->meta_root_obj); if (rstate->meta_parser != NULL) ucl_parser_free(rstate->meta_parser); } static int load_vmmem_file(const char *filename, struct restore_state *rstate) { struct stat sb; int err; rstate->vmmem_fd = open(filename, O_RDONLY); if (rstate->vmmem_fd < 0) { perror("Failed to open restore file"); return (-1); } err = fstat(rstate->vmmem_fd, &sb); if (err < 0) { perror("Failed to stat restore file"); goto err_load_vmmem; } if (sb.st_size == 0) { fprintf(stderr, "Restore file is empty.\n"); goto err_load_vmmem; } rstate->vmmem_len = sb.st_size; return (0); err_load_vmmem: if (rstate->vmmem_fd > 0) close(rstate->vmmem_fd); return (-1); } static int load_kdata_file(const char *filename, struct restore_state *rstate) { struct stat sb; int err; rstate->kdata_fd = open(filename, O_RDONLY); if (rstate->kdata_fd < 0) { perror("Failed to open kernel data file"); return (-1); } err = fstat(rstate->kdata_fd, &sb); if (err < 0) { perror("Failed to stat kernel data file"); goto err_load_kdata; } if (sb.st_size == 0) { fprintf(stderr, "Kernel data file is empty.\n"); goto err_load_kdata; } rstate->kdata_len = sb.st_size; rstate->kdata_map = mmap(NULL, rstate->kdata_len, PROT_READ, MAP_SHARED, rstate->kdata_fd, 0); if (rstate->kdata_map == MAP_FAILED) { perror("Failed to map restore file"); goto err_load_kdata; } return (0); err_load_kdata: if (rstate->kdata_fd > 0) close(rstate->kdata_fd); return (-1); } static int load_metadata_file(const char *filename, struct restore_state *rstate) { ucl_object_t *obj; struct ucl_parser *parser; int err; parser = ucl_parser_new(UCL_PARSER_DEFAULT); if (parser == NULL) { fprintf(stderr, "Failed to initialize UCL parser.\n"); err = -1; goto err_load_metadata; } err = ucl_parser_add_file(parser, filename); if (err == 0) { fprintf(stderr, "Failed to parse metadata file: '%s'\n", filename); err = -1; goto err_load_metadata; } obj = ucl_parser_get_object(parser); if (obj == NULL) { fprintf(stderr, "Failed to parse object.\n"); err = -1; goto err_load_metadata; } rstate->meta_parser = parser; rstate->meta_root_obj = (ucl_object_t *)obj; return (0); err_load_metadata: if (parser != NULL) ucl_parser_free(parser); return (err); } int load_restore_file(const char *filename, struct restore_state *rstate) { int err = 0; char *kdata_filename = NULL, *meta_filename = NULL; assert(filename != NULL); assert(rstate != NULL); memset(rstate, 0, sizeof(*rstate)); rstate->kdata_map = MAP_FAILED; err = load_vmmem_file(filename, rstate); if (err != 0) { fprintf(stderr, "Failed to load guest RAM file.\n"); goto err_restore; } kdata_filename = strcat_extension(filename, ".kern"); if (kdata_filename == NULL) { fprintf(stderr, "Failed to construct kernel data filename.\n"); goto err_restore; } err = load_kdata_file(kdata_filename, rstate); if (err != 0) { fprintf(stderr, "Failed to load guest kernel data file.\n"); goto err_restore; } meta_filename = strcat_extension(filename, ".meta"); if (meta_filename == NULL) { fprintf(stderr, "Failed to construct kernel metadata filename.\n"); goto err_restore; } err = load_metadata_file(meta_filename, rstate); if (err != 0) { fprintf(stderr, "Failed to load guest metadata file.\n"); goto err_restore; } return (0); err_restore: destroy_restore_state(rstate); if (kdata_filename != NULL) free(kdata_filename); if (meta_filename != NULL) free(meta_filename); return (-1); } #define JSON_GET_INT_OR_RETURN(key, obj, result_ptr, ret) \ do { \ const ucl_object_t *obj__; \ obj__ = ucl_object_lookup(obj, key); \ if (obj__ == NULL) { \ fprintf(stderr, "Missing key: '%s'", key); \ return (ret); \ } \ if (!ucl_object_toint_safe(obj__, result_ptr)) { \ fprintf(stderr, "Cannot convert '%s' value to int.", key); \ return (ret); \ } \ } while(0) #define JSON_GET_STRING_OR_RETURN(key, obj, result_ptr, ret) \ do { \ const ucl_object_t *obj__; \ obj__ = ucl_object_lookup(obj, key); \ if (obj__ == NULL) { \ fprintf(stderr, "Missing key: '%s'", key); \ return (ret); \ } \ if (!ucl_object_tostring_safe(obj__, result_ptr)) { \ fprintf(stderr, "Cannot convert '%s' value to string.", key); \ return (ret); \ } \ } while(0) static void * lookup_struct(enum snapshot_req struct_id, struct restore_state *rstate, size_t *struct_size) { const ucl_object_t *structs = NULL, *obj = NULL; ucl_object_iter_t it = NULL; int64_t snapshot_req, size, file_offset; structs = ucl_object_lookup(rstate->meta_root_obj, JSON_STRUCT_ARR_KEY); if (structs == NULL) { fprintf(stderr, "Failed to find '%s' object.\n", JSON_STRUCT_ARR_KEY); return (NULL); } if (ucl_object_type(structs) != UCL_ARRAY) { fprintf(stderr, "Object '%s' is not an array.\n", JSON_STRUCT_ARR_KEY); return (NULL); } while ((obj = ucl_object_iterate(structs, &it, true)) != NULL) { snapshot_req = -1; JSON_GET_INT_OR_RETURN(JSON_SNAPSHOT_REQ_KEY, obj, &snapshot_req, NULL); assert(snapshot_req >= 0); if ((enum snapshot_req) snapshot_req == struct_id) { JSON_GET_INT_OR_RETURN(JSON_SIZE_KEY, obj, &size, NULL); assert(size >= 0); JSON_GET_INT_OR_RETURN(JSON_FILE_OFFSET_KEY, obj, &file_offset, NULL); assert(file_offset >= 0); assert((uint64_t)file_offset + size <= rstate->kdata_len); *struct_size = (size_t)size; return ((uint8_t *)rstate->kdata_map + file_offset); } } return (NULL); } static void * lookup_check_dev(const char *dev_name, struct restore_state *rstate, const ucl_object_t *obj, size_t *data_size) { const char *snapshot_req; int64_t size, file_offset; snapshot_req = NULL; JSON_GET_STRING_OR_RETURN(JSON_SNAPSHOT_REQ_KEY, obj, &snapshot_req, NULL); assert(snapshot_req != NULL); if (!strcmp(snapshot_req, dev_name)) { JSON_GET_INT_OR_RETURN(JSON_SIZE_KEY, obj, &size, NULL); assert(size >= 0); JSON_GET_INT_OR_RETURN(JSON_FILE_OFFSET_KEY, obj, &file_offset, NULL); assert(file_offset >= 0); assert((uint64_t)file_offset + size <= rstate->kdata_len); *data_size = (size_t)size; return ((uint8_t *)rstate->kdata_map + file_offset); } return (NULL); } static void* lookup_dev(const char *dev_name, struct restore_state *rstate, size_t *data_size) { const ucl_object_t *devs = NULL, *obj = NULL; ucl_object_iter_t it = NULL; void *ret; devs = ucl_object_lookup(rstate->meta_root_obj, JSON_DEV_ARR_KEY); if (devs == NULL) { fprintf(stderr, "Failed to find '%s' object.\n", JSON_DEV_ARR_KEY); return (NULL); } if (ucl_object_type(devs) != UCL_ARRAY) { fprintf(stderr, "Object '%s' is not an array.\n", JSON_DEV_ARR_KEY); return (NULL); } while ((obj = ucl_object_iterate(devs, &it, true)) != NULL) { ret = lookup_check_dev(dev_name, rstate, obj, data_size); if (ret != NULL) return (ret); } return (NULL); } static const ucl_object_t * lookup_basic_metadata_object(struct restore_state *rstate) { const ucl_object_t *basic_meta_obj = NULL; basic_meta_obj = ucl_object_lookup(rstate->meta_root_obj, JSON_BASIC_METADATA_KEY); if (basic_meta_obj == NULL) { fprintf(stderr, "Failed to find '%s' object.\n", JSON_BASIC_METADATA_KEY); return (NULL); } if (ucl_object_type(basic_meta_obj) != UCL_OBJECT) { fprintf(stderr, "Object '%s' is not a JSON object.\n", JSON_BASIC_METADATA_KEY); return (NULL); } return (basic_meta_obj); } const char * lookup_vmname(struct restore_state *rstate) { const char *vmname; const ucl_object_t *obj; obj = lookup_basic_metadata_object(rstate); if (obj == NULL) return (NULL); JSON_GET_STRING_OR_RETURN(JSON_VMNAME_KEY, obj, &vmname, NULL); return (vmname); } int lookup_memflags(struct restore_state *rstate) { int64_t memflags; const ucl_object_t *obj; obj = lookup_basic_metadata_object(rstate); if (obj == NULL) return (0); JSON_GET_INT_OR_RETURN(JSON_MEMFLAGS_KEY, obj, &memflags, 0); return ((int)memflags); } size_t lookup_memsize(struct restore_state *rstate) { int64_t memsize; const ucl_object_t *obj; obj = lookup_basic_metadata_object(rstate); if (obj == NULL) return (0); JSON_GET_INT_OR_RETURN(JSON_MEMSIZE_KEY, obj, &memsize, 0); if (memsize < 0) memsize = 0; return ((size_t)memsize); } int lookup_guest_ncpus(struct restore_state *rstate) { int64_t ncpus; const ucl_object_t *obj; obj = lookup_basic_metadata_object(rstate); if (obj == NULL) return (0); JSON_GET_INT_OR_RETURN(JSON_NCPUS_KEY, obj, &ncpus, 0); return ((int)ncpus); } static void winch_handler(int signal __unused) { #ifdef TIOCGWINSZ ioctl(STDOUT_FILENO, TIOCGWINSZ, &winsize); #endif /* TIOCGWINSZ */ } static int print_progress(size_t crtval, const size_t maxval) { size_t rc; double crtval_gb, maxval_gb; size_t i, win_width, prog_start, prog_done, prog_end; int mval_len; static char prog_buf[PROG_BUF_SZ]; static const size_t len = sizeof(prog_buf); static size_t div; static const char *div_str; static char wip_bar[] = { '/', '-', '\\', '|' }; static int wip_idx = 0; if (maxval == 0) { printf("[0B / 0B]\r\n"); return (0); } if (crtval > maxval) crtval = maxval; if (maxval > 10 * GB) { div = GB; div_str = "GiB"; } else if (maxval > 10 * MB) { div = MB; div_str = "MiB"; } else { div = KB; div_str = "KiB"; } crtval_gb = (double) crtval / div; maxval_gb = (double) maxval / div; rc = snprintf(prog_buf, len, "%.03lf", maxval_gb); if (rc == len) { fprintf(stderr, "Maxval too big\n"); return (-1); } mval_len = rc; rc = snprintf(prog_buf, len, "\r[%*.03lf%s / %.03lf%s] |", mval_len, crtval_gb, div_str, maxval_gb, div_str); if (rc == len) { fprintf(stderr, "Buffer too small to print progress\n"); return (-1); } win_width = min(winsize.ws_col, len); prog_start = rc; if (prog_start < (win_width - 2)) { prog_end = win_width - prog_start - 2; prog_done = prog_end * (crtval_gb / maxval_gb); for (i = prog_start; i < prog_start + prog_done; i++) prog_buf[i] = '#'; if (crtval != maxval) { prog_buf[i] = wip_bar[wip_idx]; wip_idx = (wip_idx + 1) % sizeof(wip_bar); i++; } else { prog_buf[i++] = '#'; } for (; i < win_width - 2; i++) prog_buf[i] = '_'; prog_buf[win_width - 2] = '|'; } prog_buf[win_width - 1] = '\0'; write(STDOUT_FILENO, prog_buf, win_width); return (0); } static void * snapshot_spinner_cb(void *arg) { int rc; size_t crtval, maxval, total; struct spinner_info *si; struct timespec ts; si = arg; if (si == NULL) pthread_exit(NULL); ts.tv_sec = 0; ts.tv_nsec = 50 * 1000 * 1000; /* 50 ms sleep time */ do { crtval = *si->crtval; maxval = si->maxval; total = si->total; rc = print_progress(crtval, total); if (rc < 0) { fprintf(stderr, "Failed to parse progress\n"); break; } nanosleep(&ts, NULL); } while (crtval < maxval); pthread_exit(NULL); return NULL; } static int vm_snapshot_mem_part(const int snapfd, const size_t foff, void *src, const size_t len, const size_t totalmem, const bool op_wr) { int rc; size_t part_done, todo, rem; ssize_t done; bool show_progress; pthread_t spinner_th; struct spinner_info *si; if (lseek(snapfd, foff, SEEK_SET) < 0) { perror("Failed to change file offset"); return (-1); } show_progress = false; if (isatty(STDIN_FILENO) && (winsize.ws_col != 0)) show_progress = true; part_done = foff; rem = len; if (show_progress) { si = &(struct spinner_info) { .crtval = &part_done, .maxval = foff + len, .total = totalmem }; rc = pthread_create(&spinner_th, 0, snapshot_spinner_cb, si); if (rc) { perror("Unable to create spinner thread"); show_progress = false; } } while (rem > 0) { if (show_progress) todo = min(SNAPSHOT_CHUNK, rem); else todo = rem; if (op_wr) done = write(snapfd, src, todo); else done = read(snapfd, src, todo); if (done < 0) { perror("Failed to write in file"); return (-1); } src = (uint8_t *)src + done; part_done += done; rem -= done; } if (show_progress) { rc = pthread_join(spinner_th, NULL); if (rc) perror("Unable to end spinner thread"); } return (0); } static size_t vm_snapshot_mem(struct vmctx *ctx, int snapfd, size_t memsz, const bool op_wr) { int ret; size_t lowmem, highmem, totalmem; char *baseaddr; ret = vm_get_guestmem_from_ctx(ctx, &baseaddr, &lowmem, &highmem); if (ret) { fprintf(stderr, "%s: unable to retrieve guest memory size\r\n", __func__); return (0); } totalmem = lowmem + highmem; if ((op_wr == false) && (totalmem != memsz)) { fprintf(stderr, "%s: mem size mismatch: %ld vs %ld\r\n", __func__, totalmem, memsz); return (0); } winsize.ws_col = 80; #ifdef TIOCGWINSZ ioctl(STDOUT_FILENO, TIOCGWINSZ, &winsize); #endif /* TIOCGWINSZ */ old_winch_handler = signal(SIGWINCH, winch_handler); ret = vm_snapshot_mem_part(snapfd, 0, baseaddr, lowmem, totalmem, op_wr); if (ret) { fprintf(stderr, "%s: Could not %s lowmem\r\n", __func__, op_wr ? "write" : "read"); totalmem = 0; goto done; } if (highmem == 0) goto done; ret = vm_snapshot_mem_part(snapfd, lowmem, baseaddr + 4*GB, highmem, totalmem, op_wr); if (ret) { fprintf(stderr, "%s: Could not %s highmem\r\n", __func__, op_wr ? "write" : "read"); totalmem = 0; goto done; } done: printf("\r\n"); signal(SIGWINCH, old_winch_handler); return (totalmem); } int restore_vm_mem(struct vmctx *ctx, struct restore_state *rstate) { size_t restored; restored = vm_snapshot_mem(ctx, rstate->vmmem_fd, rstate->vmmem_len, false); if (restored != rstate->vmmem_len) return (-1); return (0); } static int vm_restore_kern_struct(struct vmctx *ctx, struct restore_state *rstate, const struct vm_snapshot_kern_info *info) { void *struct_ptr; size_t struct_size; int ret; struct vm_snapshot_meta *meta; struct_ptr = lookup_struct(info->req, rstate, &struct_size); if (struct_ptr == NULL) { fprintf(stderr, "%s: Failed to lookup struct %s\r\n", __func__, info->struct_name); ret = -1; goto done; } if (struct_size == 0) { fprintf(stderr, "%s: Kernel struct size was 0 for: %s\r\n", __func__, info->struct_name); ret = -1; goto done; } meta = &(struct vm_snapshot_meta) { .dev_name = info->struct_name, .dev_req = info->req, .buffer.buf_start = struct_ptr, .buffer.buf_size = struct_size, .buffer.buf = struct_ptr, .buffer.buf_rem = struct_size, .op = VM_SNAPSHOT_RESTORE, }; ret = vm_snapshot_req(ctx, meta); if (ret != 0) { fprintf(stderr, "%s: Failed to restore struct: %s\r\n", __func__, info->struct_name); goto done; } done: return (ret); } int vm_restore_kern_structs(struct vmctx *ctx, struct restore_state *rstate) { size_t i; int ret; for (i = 0; i < nitems(snapshot_kern_structs); i++) { ret = vm_restore_kern_struct(ctx, rstate, &snapshot_kern_structs[i]); if (ret != 0) return (ret); } return (0); } static int vm_restore_user_dev(struct restore_state *rstate, const struct vm_snapshot_dev_info *info) { void *dev_ptr; size_t dev_size; int ret; struct vm_snapshot_meta *meta; dev_ptr = lookup_dev(info->dev_name, rstate, &dev_size); if (dev_ptr == NULL) { fprintf(stderr, "Failed to lookup dev: %s\r\n", info->dev_name); fprintf(stderr, "Continuing the restore/migration process\r\n"); return (0); } if (dev_size == 0) { fprintf(stderr, "%s: Device size is 0. " "Assuming %s is not used\r\n", __func__, info->dev_name); return (0); } meta = &(struct vm_snapshot_meta) { .dev_name = info->dev_name, .buffer.buf_start = dev_ptr, .buffer.buf_size = dev_size, .buffer.buf = dev_ptr, .buffer.buf_rem = dev_size, .op = VM_SNAPSHOT_RESTORE, }; ret = (*info->snapshot_cb)(meta); if (ret != 0) { fprintf(stderr, "Failed to restore dev: %s\r\n", info->dev_name); return (-1); } return (0); } int vm_restore_user_devs(struct restore_state *rstate) { size_t i; int ret; for (i = 0; i < nitems(snapshot_devs); i++) { ret = vm_restore_user_dev(rstate, &snapshot_devs[i]); if (ret != 0) return (ret); } return 0; } int vm_pause_user_devs(void) { const struct vm_snapshot_dev_info *info; size_t i; int ret; for (i = 0; i < nitems(snapshot_devs); i++) { info = &snapshot_devs[i]; if (info->pause_cb == NULL) continue; ret = info->pause_cb(info->dev_name); if (ret != 0) return (ret); } return (0); } int vm_resume_user_devs(void) { const struct vm_snapshot_dev_info *info; size_t i; int ret; for (i = 0; i < nitems(snapshot_devs); i++) { info = &snapshot_devs[i]; if (info->resume_cb == NULL) continue; ret = info->resume_cb(info->dev_name); if (ret != 0) return (ret); } return (0); } static int vm_snapshot_kern_struct(struct vmctx *ctx, int data_fd, xo_handle_t *xop, const char *array_key, struct vm_snapshot_meta *meta, off_t *offset) { int ret; size_t data_size; ssize_t write_cnt; ret = vm_snapshot_req(ctx, meta); if (ret != 0) { fprintf(stderr, "%s: Failed to snapshot struct %s\r\n", __func__, meta->dev_name); ret = -1; goto done; } data_size = vm_get_snapshot_size(meta); /* XXX-MJ no handling for short writes. */ write_cnt = write(data_fd, meta->buffer.buf_start, data_size); if (write_cnt < 0 || (size_t)write_cnt != data_size) { perror("Failed to write all snapshotted data."); ret = -1; goto done; } /* Write metadata. */ xo_open_instance_h(xop, array_key); xo_emit_h(xop, "{:debug_name/%s}\n", meta->dev_name); xo_emit_h(xop, "{:" JSON_SNAPSHOT_REQ_KEY "/%d}\n", meta->dev_req); xo_emit_h(xop, "{:" JSON_SIZE_KEY "/%lu}\n", data_size); xo_emit_h(xop, "{:" JSON_FILE_OFFSET_KEY "/%lu}\n", *offset); xo_close_instance_h(xop, JSON_STRUCT_ARR_KEY); *offset += data_size; done: return (ret); } static int vm_snapshot_kern_structs(struct vmctx *ctx, int data_fd, xo_handle_t *xop) { int ret, error; size_t buf_size, i, offset; char *buffer; struct vm_snapshot_meta *meta; error = 0; offset = 0; buf_size = SNAPSHOT_BUFFER_SIZE; buffer = malloc(SNAPSHOT_BUFFER_SIZE * sizeof(char)); if (buffer == NULL) { error = ENOMEM; perror("Failed to allocate memory for snapshot buffer"); goto err_vm_snapshot_kern_data; } meta = &(struct vm_snapshot_meta) { .buffer.buf_start = buffer, .buffer.buf_size = buf_size, .op = VM_SNAPSHOT_SAVE, }; xo_open_list_h(xop, JSON_STRUCT_ARR_KEY); for (i = 0; i < nitems(snapshot_kern_structs); i++) { meta->dev_name = snapshot_kern_structs[i].struct_name; meta->dev_req = snapshot_kern_structs[i].req; memset(meta->buffer.buf_start, 0, meta->buffer.buf_size); meta->buffer.buf = meta->buffer.buf_start; meta->buffer.buf_rem = meta->buffer.buf_size; ret = vm_snapshot_kern_struct(ctx, data_fd, xop, JSON_DEV_ARR_KEY, meta, &offset); if (ret != 0) { error = -1; goto err_vm_snapshot_kern_data; } } xo_close_list_h(xop, JSON_STRUCT_ARR_KEY); err_vm_snapshot_kern_data: if (buffer != NULL) free(buffer); return (error); } static int vm_snapshot_basic_metadata(struct vmctx *ctx, xo_handle_t *xop, size_t memsz) { xo_open_container_h(xop, JSON_BASIC_METADATA_KEY); xo_emit_h(xop, "{:" JSON_NCPUS_KEY "/%ld}\n", guest_ncpus); xo_emit_h(xop, "{:" JSON_VMNAME_KEY "/%s}\n", vm_get_name(ctx)); xo_emit_h(xop, "{:" JSON_MEMSIZE_KEY "/%lu}\n", memsz); xo_emit_h(xop, "{:" JSON_MEMFLAGS_KEY "/%d}\n", vm_get_memflags(ctx)); xo_close_container_h(xop, JSON_BASIC_METADATA_KEY); return (0); } static int vm_snapshot_dev_write_data(int data_fd, xo_handle_t *xop, const char *array_key, struct vm_snapshot_meta *meta, off_t *offset) { ssize_t ret; size_t data_size; data_size = vm_get_snapshot_size(meta); /* XXX-MJ no handling for short writes. */ ret = write(data_fd, meta->buffer.buf_start, data_size); if (ret < 0 || (size_t)ret != data_size) { perror("Failed to write all snapshotted data."); return (-1); } /* Write metadata. */ xo_open_instance_h(xop, array_key); xo_emit_h(xop, "{:" JSON_SNAPSHOT_REQ_KEY "/%s}\n", meta->dev_name); xo_emit_h(xop, "{:" JSON_SIZE_KEY "/%lu}\n", data_size); xo_emit_h(xop, "{:" JSON_FILE_OFFSET_KEY "/%lu}\n", *offset); xo_close_instance_h(xop, array_key); *offset += data_size; return (0); } static int vm_snapshot_user_dev(const struct vm_snapshot_dev_info *info, int data_fd, xo_handle_t *xop, struct vm_snapshot_meta *meta, off_t *offset) { int ret; ret = (*info->snapshot_cb)(meta); if (ret != 0) { fprintf(stderr, "Failed to snapshot %s; ret=%d\r\n", meta->dev_name, ret); return (ret); } ret = vm_snapshot_dev_write_data(data_fd, xop, JSON_DEV_ARR_KEY, meta, offset); if (ret != 0) return (ret); return (0); } static int vm_snapshot_user_devs(int data_fd, xo_handle_t *xop) { int ret; off_t offset; void *buffer; size_t buf_size, i; struct vm_snapshot_meta *meta; buf_size = SNAPSHOT_BUFFER_SIZE; offset = lseek(data_fd, 0, SEEK_CUR); if (offset < 0) { perror("Failed to get data file current offset."); return (-1); } buffer = malloc(buf_size); if (buffer == NULL) { perror("Failed to allocate memory for snapshot buffer"); ret = ENOSPC; goto snapshot_err; } meta = &(struct vm_snapshot_meta) { .buffer.buf_start = buffer, .buffer.buf_size = buf_size, .op = VM_SNAPSHOT_SAVE, }; xo_open_list_h(xop, JSON_DEV_ARR_KEY); /* Restore other devices that support this feature */ for (i = 0; i < nitems(snapshot_devs); i++) { meta->dev_name = snapshot_devs[i].dev_name; memset(meta->buffer.buf_start, 0, meta->buffer.buf_size); meta->buffer.buf = meta->buffer.buf_start; meta->buffer.buf_rem = meta->buffer.buf_size; ret = vm_snapshot_user_dev(&snapshot_devs[i], data_fd, xop, meta, &offset); if (ret != 0) goto snapshot_err; } xo_close_list_h(xop, JSON_DEV_ARR_KEY); snapshot_err: if (buffer != NULL) free(buffer); return (ret); } void checkpoint_cpu_add(int vcpu) { pthread_mutex_lock(&vcpu_lock); CPU_SET(vcpu, &vcpus_active); if (checkpoint_active) { CPU_SET(vcpu, &vcpus_suspended); while (checkpoint_active) pthread_cond_wait(&vcpus_can_run, &vcpu_lock); CPU_CLR(vcpu, &vcpus_suspended); } pthread_mutex_unlock(&vcpu_lock); } /* * When a vCPU is suspended for any reason, it calls * checkpoint_cpu_suspend(). This records that the vCPU is idle. * Before returning from suspension, checkpoint_cpu_resume() is * called. In suspend we note that the vCPU is idle. In resume we * pause the vCPU thread until the checkpoint is complete. The reason * for the two-step process is that vCPUs might already be stopped in * the debug server when a checkpoint is requested. This approach * allows us to account for and handle those vCPUs. */ void checkpoint_cpu_suspend(int vcpu) { pthread_mutex_lock(&vcpu_lock); CPU_SET(vcpu, &vcpus_suspended); if (checkpoint_active && CPU_CMP(&vcpus_active, &vcpus_suspended) == 0) pthread_cond_signal(&vcpus_idle); pthread_mutex_unlock(&vcpu_lock); } void checkpoint_cpu_resume(int vcpu) { pthread_mutex_lock(&vcpu_lock); while (checkpoint_active) pthread_cond_wait(&vcpus_can_run, &vcpu_lock); CPU_CLR(vcpu, &vcpus_suspended); pthread_mutex_unlock(&vcpu_lock); } static void vm_vcpu_pause(struct vmctx *ctx) { pthread_mutex_lock(&vcpu_lock); checkpoint_active = true; vm_suspend_all_cpus(ctx); while (CPU_CMP(&vcpus_active, &vcpus_suspended) != 0) pthread_cond_wait(&vcpus_idle, &vcpu_lock); pthread_mutex_unlock(&vcpu_lock); } static void vm_vcpu_resume(struct vmctx *ctx) { pthread_mutex_lock(&vcpu_lock); checkpoint_active = false; pthread_mutex_unlock(&vcpu_lock); vm_resume_all_cpus(ctx); pthread_cond_broadcast(&vcpus_can_run); } static int vm_checkpoint(struct vmctx *ctx, int fddir, const char *checkpoint_file, bool stop_vm) { int fd_checkpoint = 0, kdata_fd = 0, fd_meta; int ret = 0; int error = 0; size_t memsz; xo_handle_t *xop = NULL; char *meta_filename = NULL; char *kdata_filename = NULL; FILE *meta_file = NULL; kdata_filename = strcat_extension(checkpoint_file, ".kern"); if (kdata_filename == NULL) { fprintf(stderr, "Failed to construct kernel data filename.\n"); return (-1); } kdata_fd = openat(fddir, kdata_filename, O_WRONLY | O_CREAT | O_TRUNC, 0700); if (kdata_fd < 0) { perror("Failed to open kernel data snapshot file."); error = -1; goto done; } fd_checkpoint = openat(fddir, checkpoint_file, O_RDWR | O_CREAT | O_TRUNC, 0700); if (fd_checkpoint < 0) { perror("Failed to create checkpoint file"); error = -1; goto done; } meta_filename = strcat_extension(checkpoint_file, ".meta"); if (meta_filename == NULL) { fprintf(stderr, "Failed to construct vm metadata filename.\n"); goto done; } fd_meta = openat(fddir, meta_filename, O_WRONLY | O_CREAT | O_TRUNC, 0700); if (fd_meta != -1) meta_file = fdopen(fd_meta, "w"); if (meta_file == NULL) { perror("Failed to open vm metadata snapshot file."); close(fd_meta); goto done; } xop = xo_create_to_file(meta_file, XO_STYLE_JSON, XOF_PRETTY); if (xop == NULL) { perror("Failed to get libxo handle on metadata file."); goto done; } vm_vcpu_pause(ctx); ret = vm_pause_user_devs(); if (ret != 0) { fprintf(stderr, "Could not pause devices\r\n"); error = ret; goto done; } memsz = vm_snapshot_mem(ctx, fd_checkpoint, 0, true); if (memsz == 0) { perror("Could not write guest memory to file"); error = -1; goto done; } ret = vm_snapshot_basic_metadata(ctx, xop, memsz); if (ret != 0) { fprintf(stderr, "Failed to snapshot vm basic metadata.\n"); error = -1; goto done; } ret = vm_snapshot_kern_structs(ctx, kdata_fd, xop); if (ret != 0) { fprintf(stderr, "Failed to snapshot vm kernel data.\n"); error = -1; goto done; } ret = vm_snapshot_user_devs(kdata_fd, xop); if (ret != 0) { fprintf(stderr, "Failed to snapshot device state.\n"); error = -1; goto done; } xo_finish_h(xop); if (stop_vm) { vm_destroy(ctx); exit(0); } done: ret = vm_resume_user_devs(); if (ret != 0) fprintf(stderr, "Could not resume devices\r\n"); vm_vcpu_resume(ctx); if (fd_checkpoint > 0) close(fd_checkpoint); if (meta_filename != NULL) free(meta_filename); if (kdata_filename != NULL) free(kdata_filename); if (xop != NULL) xo_destroy(xop); if (meta_file != NULL) fclose(meta_file); if (kdata_fd > 0) close(kdata_fd); return (error); } static int handle_message(struct vmctx *ctx, nvlist_t *nvl) { const char *cmd; struct ipc_command **ipc_cmd; if (!nvlist_exists_string(nvl, "cmd")) return (EINVAL); cmd = nvlist_get_string(nvl, "cmd"); IPC_COMMAND_FOREACH(ipc_cmd, ipc_cmd_set) { if (strcmp(cmd, (*ipc_cmd)->name) == 0) return ((*ipc_cmd)->handler(ctx, nvl)); } return (EOPNOTSUPP); } /* * Listen for commands from bhyvectl */ void * checkpoint_thread(void *param) { int fd; struct checkpoint_thread_info *thread_info; nvlist_t *nvl; pthread_set_name_np(pthread_self(), "checkpoint thread"); thread_info = (struct checkpoint_thread_info *)param; while ((fd = accept(thread_info->socket_fd, NULL, NULL)) != -1) { nvl = nvlist_recv(fd, 0); if (nvl != NULL) handle_message(thread_info->ctx, nvl); else EPRINTLN("nvlist_recv() failed: %s", strerror(errno)); close(fd); nvlist_destroy(nvl); } return (NULL); } static int vm_do_checkpoint(struct vmctx *ctx, const nvlist_t *nvl) { int error; if (!nvlist_exists_string(nvl, "filename") || !nvlist_exists_bool(nvl, "suspend") || !nvlist_exists_descriptor(nvl, "fddir")) error = EINVAL; else error = vm_checkpoint(ctx, nvlist_get_descriptor(nvl, "fddir"), nvlist_get_string(nvl, "filename"), nvlist_get_bool(nvl, "suspend")); return (error); } IPC_COMMAND(ipc_cmd_set, checkpoint, vm_do_checkpoint); void init_snapshot(void) { int err; err = pthread_mutex_init(&vcpu_lock, NULL); if (err != 0) errc(1, err, "checkpoint mutex init"); err = pthread_cond_init(&vcpus_idle, NULL); if (err != 0) errc(1, err, "checkpoint cv init (vcpus_idle)"); err = pthread_cond_init(&vcpus_can_run, NULL); if (err != 0) errc(1, err, "checkpoint cv init (vcpus_can_run)"); } /* * Create the listening socket for IPC with bhyvectl */ int init_checkpoint_thread(struct vmctx *ctx) { struct checkpoint_thread_info *checkpoint_info = NULL; struct sockaddr_un addr; int socket_fd; pthread_t checkpoint_pthread; int err; #ifndef WITHOUT_CAPSICUM cap_rights_t rights; #endif memset(&addr, 0, sizeof(addr)); socket_fd = socket(PF_UNIX, SOCK_STREAM, 0); if (socket_fd < 0) { EPRINTLN("Socket creation failed: %s", strerror(errno)); err = -1; goto fail; } addr.sun_family = AF_UNIX; snprintf(addr.sun_path, sizeof(addr.sun_path), "%s%s", BHYVE_RUN_DIR, vm_get_name(ctx)); addr.sun_len = SUN_LEN(&addr); unlink(addr.sun_path); if (bind(socket_fd, (struct sockaddr *)&addr, addr.sun_len) != 0) { EPRINTLN("Failed to bind socket \"%s\": %s\n", addr.sun_path, strerror(errno)); err = -1; goto fail; } if (listen(socket_fd, 10) < 0) { EPRINTLN("ipc socket listen: %s\n", strerror(errno)); err = errno; goto fail; } #ifndef WITHOUT_CAPSICUM cap_rights_init(&rights, CAP_ACCEPT, CAP_READ, CAP_RECV, CAP_WRITE, CAP_SEND, CAP_GETSOCKOPT); if (caph_rights_limit(socket_fd, &rights) == -1) errx(EX_OSERR, "Unable to apply rights for sandbox"); #endif checkpoint_info = calloc(1, sizeof(*checkpoint_info)); checkpoint_info->ctx = ctx; checkpoint_info->socket_fd = socket_fd; err = pthread_create(&checkpoint_pthread, NULL, checkpoint_thread, checkpoint_info); if (err != 0) goto fail; return (0); fail: free(checkpoint_info); if (socket_fd > 0) close(socket_fd); unlink(addr.sun_path); return (err); } void vm_snapshot_buf_err(const char *bufname, const enum vm_snapshot_op op) { const char *__op; if (op == VM_SNAPSHOT_SAVE) __op = "save"; else if (op == VM_SNAPSHOT_RESTORE) __op = "restore"; else __op = "unknown"; fprintf(stderr, "%s: snapshot-%s failed for %s\r\n", __func__, __op, bufname); } int vm_snapshot_buf(void *data, size_t data_size, struct vm_snapshot_meta *meta) { struct vm_snapshot_buffer *buffer; int op; buffer = &meta->buffer; op = meta->op; if (buffer->buf_rem < data_size) { fprintf(stderr, "%s: buffer too small\r\n", __func__); return (E2BIG); } if (op == VM_SNAPSHOT_SAVE) memcpy(buffer->buf, data, data_size); else if (op == VM_SNAPSHOT_RESTORE) memcpy(data, buffer->buf, data_size); else return (EINVAL); buffer->buf += data_size; buffer->buf_rem -= data_size; return (0); } size_t vm_get_snapshot_size(struct vm_snapshot_meta *meta) { size_t length; struct vm_snapshot_buffer *buffer; buffer = &meta->buffer; if (buffer->buf_size < buffer->buf_rem) { fprintf(stderr, "%s: Invalid buffer: size = %zu, rem = %zu\r\n", __func__, buffer->buf_size, buffer->buf_rem); length = 0; } else { length = buffer->buf_size - buffer->buf_rem; } return (length); } int vm_snapshot_guest2host_addr(struct vmctx *ctx, void **addrp, size_t len, bool restore_null, struct vm_snapshot_meta *meta) { int ret; vm_paddr_t gaddr; if (meta->op == VM_SNAPSHOT_SAVE) { gaddr = paddr_host2guest(ctx, *addrp); if (gaddr == (vm_paddr_t) -1) { if (!restore_null || (restore_null && (*addrp != NULL))) { ret = EFAULT; goto done; } } SNAPSHOT_VAR_OR_LEAVE(gaddr, meta, ret, done); } else if (meta->op == VM_SNAPSHOT_RESTORE) { SNAPSHOT_VAR_OR_LEAVE(gaddr, meta, ret, done); if (gaddr == (vm_paddr_t) -1) { if (!restore_null) { ret = EFAULT; goto done; } } *addrp = paddr_guest2host(ctx, gaddr, len); } else { ret = EINVAL; } done: return (ret); } int vm_snapshot_buf_cmp(void *data, size_t data_size, struct vm_snapshot_meta *meta) { struct vm_snapshot_buffer *buffer; int op; int ret; buffer = &meta->buffer; op = meta->op; if (buffer->buf_rem < data_size) { fprintf(stderr, "%s: buffer too small\r\n", __func__); ret = E2BIG; goto done; } if (op == VM_SNAPSHOT_SAVE) { ret = 0; memcpy(buffer->buf, data, data_size); } else if (op == VM_SNAPSHOT_RESTORE) { ret = memcmp(data, buffer->buf, data_size); } else { ret = EINVAL; goto done; } buffer->buf += data_size; buffer->buf_rem -= data_size; done: return (ret); }