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[Qemu-devel] [PATCHv2] migration: move ram migration support
|
From: |
Michael S. Tsirkin |
|
Subject: |
[Qemu-devel] [PATCHv2] migration: move ram migration support |
|
Date: |
Thu, 7 Mar 2013 15:32:48 +0200 |
Move RAM migration code from arch_init to savevm-ram.
Signed-off-by: Michael S. Tsirkin <address@hidden>
---
Note: this is on top of Juan's pull request
Changes from v1:
- renamed source file, rebased on top of migration.next as
suggested by Paolo
Makefile.target | 2 +-
arch_init.c | 763 -----------------------------------------------------
savevm-ram.c | 804 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 805 insertions(+), 764 deletions(-)
create mode 100644 savevm-ram.c
diff --git a/Makefile.target b/Makefile.target
index ca657b3..54bc21b 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -108,7 +108,7 @@ CONFIG_NO_XEN = $(if $(subst n,,$(CONFIG_XEN)),n,y)
CONFIG_NO_GET_MEMORY_MAPPING = $(if $(subst
n,,$(CONFIG_HAVE_GET_MEMORY_MAPPING)),n,y)
CONFIG_NO_CORE_DUMP = $(if $(subst n,,$(CONFIG_HAVE_CORE_DUMP)),n,y)
-obj-y += arch_init.o cpus.o monitor.o gdbstub.o balloon.o ioport.o
+obj-y += arch_init.o cpus.o monitor.o gdbstub.o balloon.o ioport.o savevm-ram.o
obj-y += qtest.o
obj-y += hw/
obj-$(CONFIG_KVM) += kvm-all.o
diff --git a/arch_init.c b/arch_init.c
index 98e2bc6..9943ed4 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -31,20 +31,15 @@
#include "config.h"
#include "monitor/monitor.h"
#include "sysemu/sysemu.h"
-#include "qemu/bitops.h"
-#include "qemu/bitmap.h"
#include "sysemu/arch_init.h"
#include "audio/audio.h"
#include "hw/pc.h"
#include "hw/pci/pci.h"
#include "hw/audiodev.h"
#include "sysemu/kvm.h"
-#include "migration/migration.h"
#include "exec/gdbstub.h"
#include "hw/smbios.h"
-#include "exec/address-spaces.h"
#include "hw/pcspk.h"
-#include "migration/page_cache.h"
#include "qemu/config-file.h"
#include "qmp-commands.h"
#include "trace.h"
@@ -103,38 +98,6 @@ int graphic_depth = 15;
const uint32_t arch_type = QEMU_ARCH;
-/***********************************************************/
-/* ram save/restore */
-
-#define RAM_SAVE_FLAG_FULL 0x01 /* Obsolete, not used anymore */
-#define RAM_SAVE_FLAG_COMPRESS 0x02
-#define RAM_SAVE_FLAG_MEM_SIZE 0x04
-#define RAM_SAVE_FLAG_PAGE 0x08
-#define RAM_SAVE_FLAG_EOS 0x10
-#define RAM_SAVE_FLAG_CONTINUE 0x20
-#define RAM_SAVE_FLAG_XBZRLE 0x40
-
-#ifdef __ALTIVEC__
-#include <altivec.h>
-#define VECTYPE vector unsigned char
-#define SPLAT(p) vec_splat(vec_ld(0, p), 0)
-#define ALL_EQ(v1, v2) vec_all_eq(v1, v2)
-/* altivec.h may redefine the bool macro as vector type.
- * Reset it to POSIX semantics. */
-#undef bool
-#define bool _Bool
-#elif defined __SSE2__
-#include <emmintrin.h>
-#define VECTYPE __m128i
-#define SPLAT(p) _mm_set1_epi8(*(p))
-#define ALL_EQ(v1, v2) (_mm_movemask_epi8(_mm_cmpeq_epi8(v1, v2)) == 0xFFFF)
-#else
-#define VECTYPE unsigned long
-#define SPLAT(p) (*(p) * (~0UL / 255))
-#define ALL_EQ(v1, v2) ((v1) == (v2))
-#endif
-
-
static struct defconfig_file {
const char *filename;
/* Indicates it is an user config file (disabled by -no-user-config) */
@@ -145,7 +108,6 @@ static struct defconfig_file {
{ NULL }, /* end of list */
};
-
int qemu_read_default_config_files(bool userconfig)
{
int ret;
@@ -164,731 +126,6 @@ int qemu_read_default_config_files(bool userconfig)
return 0;
}
-static int is_dup_page(uint8_t *page)
-{
- VECTYPE *p = (VECTYPE *)page;
- VECTYPE val = SPLAT(page);
- int i;
-
- for (i = 0; i < TARGET_PAGE_SIZE / sizeof(VECTYPE); i++) {
- if (!ALL_EQ(val, p[i])) {
- return 0;
- }
- }
-
- return 1;
-}
-
-/* struct contains XBZRLE cache and a static page
- used by the compression */
-static struct {
- /* buffer used for XBZRLE encoding */
- uint8_t *encoded_buf;
- /* buffer for storing page content */
- uint8_t *current_buf;
- /* buffer used for XBZRLE decoding */
- uint8_t *decoded_buf;
- /* Cache for XBZRLE */
- PageCache *cache;
-} XBZRLE = {
- .encoded_buf = NULL,
- .current_buf = NULL,
- .decoded_buf = NULL,
- .cache = NULL,
-};
-
-
-int64_t xbzrle_cache_resize(int64_t new_size)
-{
- if (XBZRLE.cache != NULL) {
- return cache_resize(XBZRLE.cache, new_size / TARGET_PAGE_SIZE) *
- TARGET_PAGE_SIZE;
- }
- return pow2floor(new_size);
-}
-
-/* accounting for migration statistics */
-typedef struct AccountingInfo {
- uint64_t dup_pages;
- uint64_t norm_pages;
- uint64_t iterations;
- uint64_t xbzrle_bytes;
- uint64_t xbzrle_pages;
- uint64_t xbzrle_cache_miss;
- uint64_t xbzrle_overflows;
-} AccountingInfo;
-
-static AccountingInfo acct_info;
-
-static void acct_clear(void)
-{
- memset(&acct_info, 0, sizeof(acct_info));
-}
-
-uint64_t dup_mig_bytes_transferred(void)
-{
- return acct_info.dup_pages * TARGET_PAGE_SIZE;
-}
-
-uint64_t dup_mig_pages_transferred(void)
-{
- return acct_info.dup_pages;
-}
-
-uint64_t norm_mig_bytes_transferred(void)
-{
- return acct_info.norm_pages * TARGET_PAGE_SIZE;
-}
-
-uint64_t norm_mig_pages_transferred(void)
-{
- return acct_info.norm_pages;
-}
-
-uint64_t xbzrle_mig_bytes_transferred(void)
-{
- return acct_info.xbzrle_bytes;
-}
-
-uint64_t xbzrle_mig_pages_transferred(void)
-{
- return acct_info.xbzrle_pages;
-}
-
-uint64_t xbzrle_mig_pages_cache_miss(void)
-{
- return acct_info.xbzrle_cache_miss;
-}
-
-uint64_t xbzrle_mig_pages_overflow(void)
-{
- return acct_info.xbzrle_overflows;
-}
-
-static size_t save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
- int cont, int flag)
-{
- size_t size;
-
- qemu_put_be64(f, offset | cont | flag);
- size = 8;
-
- if (!cont) {
- qemu_put_byte(f, strlen(block->idstr));
- qemu_put_buffer(f, (uint8_t *)block->idstr,
- strlen(block->idstr));
- size += 1 + strlen(block->idstr);
- }
- return size;
-}
-
-#define ENCODING_FLAG_XBZRLE 0x1
-
-static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,
- ram_addr_t current_addr, RAMBlock *block,
- ram_addr_t offset, int cont, bool last_stage)
-{
- int encoded_len = 0, bytes_sent = -1;
- uint8_t *prev_cached_page;
-
- if (!cache_is_cached(XBZRLE.cache, current_addr)) {
- if (!last_stage) {
- cache_insert(XBZRLE.cache, current_addr, current_data);
- }
- acct_info.xbzrle_cache_miss++;
- return -1;
- }
-
- prev_cached_page = get_cached_data(XBZRLE.cache, current_addr);
-
- /* save current buffer into memory */
- memcpy(XBZRLE.current_buf, current_data, TARGET_PAGE_SIZE);
-
- /* XBZRLE encoding (if there is no overflow) */
- encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf,
- TARGET_PAGE_SIZE, XBZRLE.encoded_buf,
- TARGET_PAGE_SIZE);
- if (encoded_len == 0) {
- DPRINTF("Skipping unmodified page\n");
- return 0;
- } else if (encoded_len == -1) {
- DPRINTF("Overflow\n");
- acct_info.xbzrle_overflows++;
- /* update data in the cache */
- memcpy(prev_cached_page, current_data, TARGET_PAGE_SIZE);
- return -1;
- }
-
- /* we need to update the data in the cache, in order to get the same data
*/
- if (!last_stage) {
- memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE);
- }
-
- /* Send XBZRLE based compressed page */
- bytes_sent = save_block_hdr(f, block, offset, cont, RAM_SAVE_FLAG_XBZRLE);
- qemu_put_byte(f, ENCODING_FLAG_XBZRLE);
- qemu_put_be16(f, encoded_len);
- qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len);
- bytes_sent += encoded_len + 1 + 2;
- acct_info.xbzrle_pages++;
- acct_info.xbzrle_bytes += bytes_sent;
-
- return bytes_sent;
-}
-
-
-/* This is the last block that we have visited serching for dirty pages
- */
-static RAMBlock *last_seen_block;
-/* This is the last block from where we have sent data */
-static RAMBlock *last_sent_block;
-static ram_addr_t last_offset;
-static unsigned long *migration_bitmap;
-static uint64_t migration_dirty_pages;
-static uint32_t last_version;
-
-static inline
-ram_addr_t migration_bitmap_find_and_reset_dirty(MemoryRegion *mr,
- ram_addr_t start)
-{
- unsigned long base = mr->ram_addr >> TARGET_PAGE_BITS;
- unsigned long nr = base + (start >> TARGET_PAGE_BITS);
- unsigned long size = base + (int128_get64(mr->size) >> TARGET_PAGE_BITS);
-
- unsigned long next = find_next_bit(migration_bitmap, size, nr);
-
- if (next < size) {
- clear_bit(next, migration_bitmap);
- migration_dirty_pages--;
- }
- return (next - base) << TARGET_PAGE_BITS;
-}
-
-static inline bool migration_bitmap_set_dirty(MemoryRegion *mr,
- ram_addr_t offset)
-{
- bool ret;
- int nr = (mr->ram_addr + offset) >> TARGET_PAGE_BITS;
-
- ret = test_and_set_bit(nr, migration_bitmap);
-
- if (!ret) {
- migration_dirty_pages++;
- }
- return ret;
-}
-
-/* Needs iothread lock! */
-
-static void migration_bitmap_sync(void)
-{
- RAMBlock *block;
- ram_addr_t addr;
- uint64_t num_dirty_pages_init = migration_dirty_pages;
- MigrationState *s = migrate_get_current();
- static int64_t start_time;
- static int64_t num_dirty_pages_period;
- int64_t end_time;
-
- if (!start_time) {
- start_time = qemu_get_clock_ms(rt_clock);
- }
-
- trace_migration_bitmap_sync_start();
- memory_global_sync_dirty_bitmap(get_system_memory());
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
- for (addr = 0; addr < block->length; addr += TARGET_PAGE_SIZE) {
- if (memory_region_test_and_clear_dirty(block->mr,
- addr, TARGET_PAGE_SIZE,
- DIRTY_MEMORY_MIGRATION)) {
- migration_bitmap_set_dirty(block->mr, addr);
- }
- }
- }
- trace_migration_bitmap_sync_end(migration_dirty_pages
- - num_dirty_pages_init);
- num_dirty_pages_period += migration_dirty_pages - num_dirty_pages_init;
- end_time = qemu_get_clock_ms(rt_clock);
-
- /* more than 1 second = 1000 millisecons */
- if (end_time > start_time + 1000) {
- s->dirty_pages_rate = num_dirty_pages_period * 1000
- / (end_time - start_time);
- s->dirty_bytes_rate = s->dirty_pages_rate * TARGET_PAGE_SIZE;
- start_time = end_time;
- num_dirty_pages_period = 0;
- }
-}
-
-/*
- * ram_save_block: Writes a page of memory to the stream f
- *
- * Returns: The number of bytes written.
- * 0 means no dirty pages
- */
-
-static int ram_save_block(QEMUFile *f, bool last_stage)
-{
- RAMBlock *block = last_seen_block;
- ram_addr_t offset = last_offset;
- bool complete_round = false;
- int bytes_sent = 0;
- MemoryRegion *mr;
- ram_addr_t current_addr;
-
- if (!block)
- block = QTAILQ_FIRST(&ram_list.blocks);
-
- while (true) {
- mr = block->mr;
- offset = migration_bitmap_find_and_reset_dirty(mr, offset);
- if (complete_round && block == last_seen_block &&
- offset >= last_offset) {
- break;
- }
- if (offset >= block->length) {
- offset = 0;
- block = QTAILQ_NEXT(block, next);
- if (!block) {
- block = QTAILQ_FIRST(&ram_list.blocks);
- complete_round = true;
- }
- } else {
- uint8_t *p;
- int cont = (block == last_sent_block) ?
- RAM_SAVE_FLAG_CONTINUE : 0;
-
- p = memory_region_get_ram_ptr(mr) + offset;
-
- /* In doubt sent page as normal */
- bytes_sent = -1;
- if (is_dup_page(p)) {
- acct_info.dup_pages++;
- bytes_sent = save_block_hdr(f, block, offset, cont,
- RAM_SAVE_FLAG_COMPRESS);
- qemu_put_byte(f, *p);
- bytes_sent += 1;
- } else if (migrate_use_xbzrle()) {
- current_addr = block->offset + offset;
- bytes_sent = save_xbzrle_page(f, p, current_addr, block,
- offset, cont, last_stage);
- if (!last_stage) {
- p = get_cached_data(XBZRLE.cache, current_addr);
- }
- }
-
- /* XBZRLE overflow or normal page */
- if (bytes_sent == -1) {
- bytes_sent = save_block_hdr(f, block, offset, cont,
RAM_SAVE_FLAG_PAGE);
- qemu_put_buffer(f, p, TARGET_PAGE_SIZE);
- bytes_sent += TARGET_PAGE_SIZE;
- acct_info.norm_pages++;
- }
-
- /* if page is unmodified, continue to the next */
- if (bytes_sent > 0) {
- last_sent_block = block;
- break;
- }
- }
- }
- last_seen_block = block;
- last_offset = offset;
-
- return bytes_sent;
-}
-
-static uint64_t bytes_transferred;
-
-static ram_addr_t ram_save_remaining(void)
-{
- return migration_dirty_pages;
-}
-
-uint64_t ram_bytes_remaining(void)
-{
- return ram_save_remaining() * TARGET_PAGE_SIZE;
-}
-
-uint64_t ram_bytes_transferred(void)
-{
- return bytes_transferred;
-}
-
-uint64_t ram_bytes_total(void)
-{
- RAMBlock *block;
- uint64_t total = 0;
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next)
- total += block->length;
-
- return total;
-}
-
-static void migration_end(void)
-{
- if (migration_bitmap) {
- memory_global_dirty_log_stop();
- g_free(migration_bitmap);
- migration_bitmap = NULL;
- }
-
- if (XBZRLE.cache) {
- cache_fini(XBZRLE.cache);
- g_free(XBZRLE.cache);
- g_free(XBZRLE.encoded_buf);
- g_free(XBZRLE.current_buf);
- g_free(XBZRLE.decoded_buf);
- XBZRLE.cache = NULL;
- }
-}
-
-static void ram_migration_cancel(void *opaque)
-{
- migration_end();
-}
-
-static void reset_ram_globals(void)
-{
- last_seen_block = NULL;
- last_sent_block = NULL;
- last_offset = 0;
- last_version = ram_list.version;
-}
-
-#define MAX_WAIT 50 /* ms, half buffered_file limit */
-
-static int ram_save_setup(QEMUFile *f, void *opaque)
-{
- RAMBlock *block;
- int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS;
-
- migration_bitmap = bitmap_new(ram_pages);
- bitmap_set(migration_bitmap, 0, ram_pages);
- migration_dirty_pages = ram_pages;
-
- if (migrate_use_xbzrle()) {
- XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() /
- TARGET_PAGE_SIZE,
- TARGET_PAGE_SIZE);
- if (!XBZRLE.cache) {
- DPRINTF("Error creating cache\n");
- return -1;
- }
- XBZRLE.encoded_buf = g_malloc0(TARGET_PAGE_SIZE);
- XBZRLE.current_buf = g_malloc(TARGET_PAGE_SIZE);
- acct_clear();
- }
-
- qemu_mutex_lock_iothread();
- qemu_mutex_lock_ramlist();
- bytes_transferred = 0;
- reset_ram_globals();
-
- memory_global_dirty_log_start();
- migration_bitmap_sync();
- qemu_mutex_unlock_iothread();
-
- qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE);
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
- qemu_put_byte(f, strlen(block->idstr));
- qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr));
- qemu_put_be64(f, block->length);
- }
-
- qemu_mutex_unlock_ramlist();
- qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
-
- return 0;
-}
-
-static int ram_save_iterate(QEMUFile *f, void *opaque)
-{
- int ret;
- int i;
- int64_t t0;
- int total_sent = 0;
-
- qemu_mutex_lock_ramlist();
-
- if (ram_list.version != last_version) {
- reset_ram_globals();
- }
-
- t0 = qemu_get_clock_ns(rt_clock);
- i = 0;
- while ((ret = qemu_file_rate_limit(f)) == 0) {
- int bytes_sent;
-
- bytes_sent = ram_save_block(f, false);
- /* no more blocks to sent */
- if (bytes_sent == 0) {
- break;
- }
- total_sent += bytes_sent;
- acct_info.iterations++;
- /* we want to check in the 1st loop, just in case it was the 1st time
- and we had to sync the dirty bitmap.
- qemu_get_clock_ns() is a bit expensive, so we only check each some
- iterations
- */
- if ((i & 63) == 0) {
- uint64_t t1 = (qemu_get_clock_ns(rt_clock) - t0) / 1000000;
- if (t1 > MAX_WAIT) {
- DPRINTF("big wait: %" PRIu64 " milliseconds, %d iterations\n",
- t1, i);
- break;
- }
- }
- i++;
- }
-
- qemu_mutex_unlock_ramlist();
-
- if (ret < 0) {
- bytes_transferred += total_sent;
- return ret;
- }
-
- qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
- total_sent += 8;
- bytes_transferred += total_sent;
-
- return total_sent;
-}
-
-static int ram_save_complete(QEMUFile *f, void *opaque)
-{
- qemu_mutex_lock_ramlist();
- migration_bitmap_sync();
-
- /* try transferring iterative blocks of memory */
-
- /* flush all remaining blocks regardless of rate limiting */
- while (true) {
- int bytes_sent;
-
- bytes_sent = ram_save_block(f, true);
- /* no more blocks to sent */
- if (bytes_sent == 0) {
- break;
- }
- bytes_transferred += bytes_sent;
- }
- migration_end();
-
- qemu_mutex_unlock_ramlist();
- qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
-
- return 0;
-}
-
-static uint64_t ram_save_pending(QEMUFile *f, void *opaque, uint64_t max_size)
-{
- uint64_t remaining_size;
-
- remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE;
-
- if (remaining_size < max_size) {
- qemu_mutex_lock_iothread();
- migration_bitmap_sync();
- qemu_mutex_unlock_iothread();
- remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE;
- }
- return remaining_size;
-}
-
-static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host)
-{
- int ret, rc = 0;
- unsigned int xh_len;
- int xh_flags;
-
- if (!XBZRLE.decoded_buf) {
- XBZRLE.decoded_buf = g_malloc(TARGET_PAGE_SIZE);
- }
-
- /* extract RLE header */
- xh_flags = qemu_get_byte(f);
- xh_len = qemu_get_be16(f);
-
- if (xh_flags != ENCODING_FLAG_XBZRLE) {
- fprintf(stderr, "Failed to load XBZRLE page - wrong compression!\n");
- return -1;
- }
-
- if (xh_len > TARGET_PAGE_SIZE) {
- fprintf(stderr, "Failed to load XBZRLE page - len overflow!\n");
- return -1;
- }
- /* load data and decode */
- qemu_get_buffer(f, XBZRLE.decoded_buf, xh_len);
-
- /* decode RLE */
- ret = xbzrle_decode_buffer(XBZRLE.decoded_buf, xh_len, host,
- TARGET_PAGE_SIZE);
- if (ret == -1) {
- fprintf(stderr, "Failed to load XBZRLE page - decode error!\n");
- rc = -1;
- } else if (ret > TARGET_PAGE_SIZE) {
- fprintf(stderr, "Failed to load XBZRLE page - size %d exceeds %d!\n",
- ret, TARGET_PAGE_SIZE);
- abort();
- }
-
- return rc;
-}
-
-static inline void *host_from_stream_offset(QEMUFile *f,
- ram_addr_t offset,
- int flags)
-{
- static RAMBlock *block = NULL;
- char id[256];
- uint8_t len;
-
- if (flags & RAM_SAVE_FLAG_CONTINUE) {
- if (!block) {
- fprintf(stderr, "Ack, bad migration stream!\n");
- return NULL;
- }
-
- return memory_region_get_ram_ptr(block->mr) + offset;
- }
-
- len = qemu_get_byte(f);
- qemu_get_buffer(f, (uint8_t *)id, len);
- id[len] = 0;
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
- if (!strncmp(id, block->idstr, sizeof(id)))
- return memory_region_get_ram_ptr(block->mr) + offset;
- }
-
- fprintf(stderr, "Can't find block %s!\n", id);
- return NULL;
-}
-
-static int ram_load(QEMUFile *f, void *opaque, int version_id)
-{
- ram_addr_t addr;
- int flags, ret = 0;
- int error;
- static uint64_t seq_iter;
-
- seq_iter++;
-
- if (version_id < 4 || version_id > 4) {
- return -EINVAL;
- }
-
- do {
- addr = qemu_get_be64(f);
-
- flags = addr & ~TARGET_PAGE_MASK;
- addr &= TARGET_PAGE_MASK;
-
- if (flags & RAM_SAVE_FLAG_MEM_SIZE) {
- if (version_id == 4) {
- /* Synchronize RAM block list */
- char id[256];
- ram_addr_t length;
- ram_addr_t total_ram_bytes = addr;
-
- while (total_ram_bytes) {
- RAMBlock *block;
- uint8_t len;
-
- len = qemu_get_byte(f);
- qemu_get_buffer(f, (uint8_t *)id, len);
- id[len] = 0;
- length = qemu_get_be64(f);
-
- QTAILQ_FOREACH(block, &ram_list.blocks, next) {
- if (!strncmp(id, block->idstr, sizeof(id))) {
- if (block->length != length) {
- ret = -EINVAL;
- goto done;
- }
- break;
- }
- }
-
- if (!block) {
- fprintf(stderr, "Unknown ramblock \"%s\", cannot "
- "accept migration\n", id);
- ret = -EINVAL;
- goto done;
- }
-
- total_ram_bytes -= length;
- }
- }
- }
-
- if (flags & RAM_SAVE_FLAG_COMPRESS) {
- void *host;
- uint8_t ch;
-
- host = host_from_stream_offset(f, addr, flags);
- if (!host) {
- return -EINVAL;
- }
-
- ch = qemu_get_byte(f);
- memset(host, ch, TARGET_PAGE_SIZE);
-#ifndef _WIN32
- if (ch == 0 &&
- (!kvm_enabled() || kvm_has_sync_mmu()) &&
- getpagesize() <= TARGET_PAGE_SIZE) {
- qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED);
- }
-#endif
- } else if (flags & RAM_SAVE_FLAG_PAGE) {
- void *host;
-
- host = host_from_stream_offset(f, addr, flags);
- if (!host) {
- return -EINVAL;
- }
-
- qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
- } else if (flags & RAM_SAVE_FLAG_XBZRLE) {
- void *host = host_from_stream_offset(f, addr, flags);
- if (!host) {
- return -EINVAL;
- }
-
- if (load_xbzrle(f, addr, host) < 0) {
- ret = -EINVAL;
- goto done;
- }
- }
- error = qemu_file_get_error(f);
- if (error) {
- ret = error;
- goto done;
- }
- } while (!(flags & RAM_SAVE_FLAG_EOS));
-
-done:
- DPRINTF("Completed load of VM with exit code %d seq iteration "
- "%" PRIu64 "\n", ret, seq_iter);
- return ret;
-}
-
-SaveVMHandlers savevm_ram_handlers = {
- .save_live_setup = ram_save_setup,
- .save_live_iterate = ram_save_iterate,
- .save_live_complete = ram_save_complete,
- .save_live_pending = ram_save_pending,
- .load_state = ram_load,
- .cancel = ram_migration_cancel,
-};
-
#ifdef HAS_AUDIO
struct soundhw {
const char *name;
diff --git a/savevm-ram.c b/savevm-ram.c
new file mode 100644
index 0000000..cea656c
--- /dev/null
+++ b/savevm-ram.c
@@ -0,0 +1,804 @@
+/*
+ * RAM Migration support
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include <stdint.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#ifndef _WIN32
+#include <sys/types.h>
+#include <sys/mman.h>
+#endif
+#include "sysemu/sysemu.h"
+#include "qemu/bitops.h"
+#include "qemu/bitmap.h"
+#include "sysemu/kvm.h"
+#include "migration/migration.h"
+#include "exec/address-spaces.h"
+#include "migration/page_cache.h"
+#include "migration/qemu-file.h"
+#include "trace.h"
+#include "exec/cpu-all.h"
+
+#ifdef DEBUG_ARCH_INIT
+#define DPRINTF(fmt, ...) \
+ do { fprintf(stdout, "arch_init: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+/***********************************************************/
+/* ram save/restore */
+
+#define RAM_SAVE_FLAG_FULL 0x01 /* Obsolete, not used anymore */
+#define RAM_SAVE_FLAG_COMPRESS 0x02
+#define RAM_SAVE_FLAG_MEM_SIZE 0x04
+#define RAM_SAVE_FLAG_PAGE 0x08
+#define RAM_SAVE_FLAG_EOS 0x10
+#define RAM_SAVE_FLAG_CONTINUE 0x20
+#define RAM_SAVE_FLAG_XBZRLE 0x40
+
+#ifdef __ALTIVEC__
+#include <altivec.h>
+#define VECTYPE vector unsigned char
+#define SPLAT(p) vec_splat(vec_ld(0, p), 0)
+#define ALL_EQ(v1, v2) vec_all_eq(v1, v2)
+/* altivec.h may redefine the bool macro as vector type.
+ * Reset it to POSIX semantics. */
+#undef bool
+#define bool _Bool
+#elif defined __SSE2__
+#include <emmintrin.h>
+#define VECTYPE __m128i
+#define SPLAT(p) _mm_set1_epi8(*(p))
+#define ALL_EQ(v1, v2) (_mm_movemask_epi8(_mm_cmpeq_epi8(v1, v2)) == 0xFFFF)
+#else
+#define VECTYPE unsigned long
+#define SPLAT(p) (*(p) * (~0UL / 255))
+#define ALL_EQ(v1, v2) ((v1) == (v2))
+#endif
+
+static int is_dup_page(uint8_t *page)
+{
+ VECTYPE *p = (VECTYPE *)page;
+ VECTYPE val = SPLAT(page);
+ int i;
+
+ for (i = 0; i < TARGET_PAGE_SIZE / sizeof(VECTYPE); i++) {
+ if (!ALL_EQ(val, p[i])) {
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+/* struct contains XBZRLE cache and a static page
+ used by the compression */
+static struct {
+ /* buffer used for XBZRLE encoding */
+ uint8_t *encoded_buf;
+ /* buffer for storing page content */
+ uint8_t *current_buf;
+ /* buffer used for XBZRLE decoding */
+ uint8_t *decoded_buf;
+ /* Cache for XBZRLE */
+ PageCache *cache;
+} XBZRLE = {
+ .encoded_buf = NULL,
+ .current_buf = NULL,
+ .decoded_buf = NULL,
+ .cache = NULL,
+};
+
+
+int64_t xbzrle_cache_resize(int64_t new_size)
+{
+ if (XBZRLE.cache != NULL) {
+ return cache_resize(XBZRLE.cache, new_size / TARGET_PAGE_SIZE) *
+ TARGET_PAGE_SIZE;
+ }
+ return pow2floor(new_size);
+}
+
+/* accounting for migration statistics */
+typedef struct AccountingInfo {
+ uint64_t dup_pages;
+ uint64_t norm_pages;
+ uint64_t iterations;
+ uint64_t xbzrle_bytes;
+ uint64_t xbzrle_pages;
+ uint64_t xbzrle_cache_miss;
+ uint64_t xbzrle_overflows;
+} AccountingInfo;
+
+static AccountingInfo acct_info;
+
+static void acct_clear(void)
+{
+ memset(&acct_info, 0, sizeof(acct_info));
+}
+
+uint64_t dup_mig_bytes_transferred(void)
+{
+ return acct_info.dup_pages * TARGET_PAGE_SIZE;
+}
+
+uint64_t dup_mig_pages_transferred(void)
+{
+ return acct_info.dup_pages;
+}
+
+uint64_t norm_mig_bytes_transferred(void)
+{
+ return acct_info.norm_pages * TARGET_PAGE_SIZE;
+}
+
+uint64_t norm_mig_pages_transferred(void)
+{
+ return acct_info.norm_pages;
+}
+
+uint64_t xbzrle_mig_bytes_transferred(void)
+{
+ return acct_info.xbzrle_bytes;
+}
+
+uint64_t xbzrle_mig_pages_transferred(void)
+{
+ return acct_info.xbzrle_pages;
+}
+
+uint64_t xbzrle_mig_pages_cache_miss(void)
+{
+ return acct_info.xbzrle_cache_miss;
+}
+
+uint64_t xbzrle_mig_pages_overflow(void)
+{
+ return acct_info.xbzrle_overflows;
+}
+
+static size_t save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
+ int cont, int flag)
+{
+ size_t size;
+
+ qemu_put_be64(f, offset | cont | flag);
+ size = 8;
+
+ if (!cont) {
+ qemu_put_byte(f, strlen(block->idstr));
+ qemu_put_buffer(f, (uint8_t *)block->idstr,
+ strlen(block->idstr));
+ size += 1 + strlen(block->idstr);
+ }
+ return size;
+}
+
+#define ENCODING_FLAG_XBZRLE 0x1
+
+static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,
+ ram_addr_t current_addr, RAMBlock *block,
+ ram_addr_t offset, int cont, bool last_stage)
+{
+ int encoded_len = 0, bytes_sent = -1;
+ uint8_t *prev_cached_page;
+
+ if (!cache_is_cached(XBZRLE.cache, current_addr)) {
+ if (!last_stage) {
+ cache_insert(XBZRLE.cache, current_addr, current_data);
+ }
+ acct_info.xbzrle_cache_miss++;
+ return -1;
+ }
+
+ prev_cached_page = get_cached_data(XBZRLE.cache, current_addr);
+
+ /* save current buffer into memory */
+ memcpy(XBZRLE.current_buf, current_data, TARGET_PAGE_SIZE);
+
+ /* XBZRLE encoding (if there is no overflow) */
+ encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf,
+ TARGET_PAGE_SIZE, XBZRLE.encoded_buf,
+ TARGET_PAGE_SIZE);
+ if (encoded_len == 0) {
+ DPRINTF("Skipping unmodified page\n");
+ return 0;
+ } else if (encoded_len == -1) {
+ DPRINTF("Overflow\n");
+ acct_info.xbzrle_overflows++;
+ /* update data in the cache */
+ memcpy(prev_cached_page, current_data, TARGET_PAGE_SIZE);
+ return -1;
+ }
+
+ /* we need to update the data in the cache, in order to get the same data
*/
+ if (!last_stage) {
+ memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE);
+ }
+
+ /* Send XBZRLE based compressed page */
+ bytes_sent = save_block_hdr(f, block, offset, cont, RAM_SAVE_FLAG_XBZRLE);
+ qemu_put_byte(f, ENCODING_FLAG_XBZRLE);
+ qemu_put_be16(f, encoded_len);
+ qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len);
+ bytes_sent += encoded_len + 1 + 2;
+ acct_info.xbzrle_pages++;
+ acct_info.xbzrle_bytes += bytes_sent;
+
+ return bytes_sent;
+}
+
+
+/* This is the last block that we have visited serching for dirty pages
+ */
+static RAMBlock *last_seen_block;
+/* This is the last block from where we have sent data */
+static RAMBlock *last_sent_block;
+static ram_addr_t last_offset;
+static unsigned long *migration_bitmap;
+static uint64_t migration_dirty_pages;
+static uint32_t last_version;
+
+static inline
+ram_addr_t migration_bitmap_find_and_reset_dirty(MemoryRegion *mr,
+ ram_addr_t start)
+{
+ unsigned long base = mr->ram_addr >> TARGET_PAGE_BITS;
+ unsigned long nr = base + (start >> TARGET_PAGE_BITS);
+ unsigned long size = base + (int128_get64(mr->size) >> TARGET_PAGE_BITS);
+
+ unsigned long next = find_next_bit(migration_bitmap, size, nr);
+
+ if (next < size) {
+ clear_bit(next, migration_bitmap);
+ migration_dirty_pages--;
+ }
+ return (next - base) << TARGET_PAGE_BITS;
+}
+
+static inline bool migration_bitmap_set_dirty(MemoryRegion *mr,
+ ram_addr_t offset)
+{
+ bool ret;
+ int nr = (mr->ram_addr + offset) >> TARGET_PAGE_BITS;
+
+ ret = test_and_set_bit(nr, migration_bitmap);
+
+ if (!ret) {
+ migration_dirty_pages++;
+ }
+ return ret;
+}
+
+/* Needs iothread lock! */
+
+static void migration_bitmap_sync(void)
+{
+ RAMBlock *block;
+ ram_addr_t addr;
+ uint64_t num_dirty_pages_init = migration_dirty_pages;
+ MigrationState *s = migrate_get_current();
+ static int64_t start_time;
+ static int64_t num_dirty_pages_period;
+ int64_t end_time;
+
+ if (!start_time) {
+ start_time = qemu_get_clock_ms(rt_clock);
+ }
+
+ trace_migration_bitmap_sync_start();
+ memory_global_sync_dirty_bitmap(get_system_memory());
+
+ QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ for (addr = 0; addr < block->length; addr += TARGET_PAGE_SIZE) {
+ if (memory_region_test_and_clear_dirty(block->mr,
+ addr, TARGET_PAGE_SIZE,
+ DIRTY_MEMORY_MIGRATION)) {
+ migration_bitmap_set_dirty(block->mr, addr);
+ }
+ }
+ }
+ trace_migration_bitmap_sync_end(migration_dirty_pages
+ - num_dirty_pages_init);
+ num_dirty_pages_period += migration_dirty_pages - num_dirty_pages_init;
+ end_time = qemu_get_clock_ms(rt_clock);
+
+ /* more than 1 second = 1000 millisecons */
+ if (end_time > start_time + 1000) {
+ s->dirty_pages_rate = num_dirty_pages_period * 1000
+ / (end_time - start_time);
+ s->dirty_bytes_rate = s->dirty_pages_rate * TARGET_PAGE_SIZE;
+ start_time = end_time;
+ num_dirty_pages_period = 0;
+ }
+}
+
+/*
+ * ram_save_block: Writes a page of memory to the stream f
+ *
+ * Returns: The number of bytes written.
+ * 0 means no dirty pages
+ */
+
+static int ram_save_block(QEMUFile *f, bool last_stage)
+{
+ RAMBlock *block = last_seen_block;
+ ram_addr_t offset = last_offset;
+ bool complete_round = false;
+ int bytes_sent = 0;
+ MemoryRegion *mr;
+ ram_addr_t current_addr;
+
+ if (!block)
+ block = QTAILQ_FIRST(&ram_list.blocks);
+
+ while (true) {
+ mr = block->mr;
+ offset = migration_bitmap_find_and_reset_dirty(mr, offset);
+ if (complete_round && block == last_seen_block &&
+ offset >= last_offset) {
+ break;
+ }
+ if (offset >= block->length) {
+ offset = 0;
+ block = QTAILQ_NEXT(block, next);
+ if (!block) {
+ block = QTAILQ_FIRST(&ram_list.blocks);
+ complete_round = true;
+ }
+ } else {
+ uint8_t *p;
+ int cont = (block == last_sent_block) ?
+ RAM_SAVE_FLAG_CONTINUE : 0;
+
+ p = memory_region_get_ram_ptr(mr) + offset;
+
+ /* In doubt sent page as normal */
+ bytes_sent = -1;
+ if (is_dup_page(p)) {
+ acct_info.dup_pages++;
+ bytes_sent = save_block_hdr(f, block, offset, cont,
+ RAM_SAVE_FLAG_COMPRESS);
+ qemu_put_byte(f, *p);
+ bytes_sent += 1;
+ } else if (migrate_use_xbzrle()) {
+ current_addr = block->offset + offset;
+ bytes_sent = save_xbzrle_page(f, p, current_addr, block,
+ offset, cont, last_stage);
+ if (!last_stage) {
+ p = get_cached_data(XBZRLE.cache, current_addr);
+ }
+ }
+
+ /* XBZRLE overflow or normal page */
+ if (bytes_sent == -1) {
+ bytes_sent = save_block_hdr(f, block, offset, cont,
RAM_SAVE_FLAG_PAGE);
+ qemu_put_buffer(f, p, TARGET_PAGE_SIZE);
+ bytes_sent += TARGET_PAGE_SIZE;
+ acct_info.norm_pages++;
+ }
+
+ /* if page is unmodified, continue to the next */
+ if (bytes_sent > 0) {
+ last_sent_block = block;
+ break;
+ }
+ }
+ }
+ last_seen_block = block;
+ last_offset = offset;
+
+ return bytes_sent;
+}
+
+static uint64_t bytes_transferred;
+
+static ram_addr_t ram_save_remaining(void)
+{
+ return migration_dirty_pages;
+}
+
+uint64_t ram_bytes_remaining(void)
+{
+ return ram_save_remaining() * TARGET_PAGE_SIZE;
+}
+
+uint64_t ram_bytes_transferred(void)
+{
+ return bytes_transferred;
+}
+
+uint64_t ram_bytes_total(void)
+{
+ RAMBlock *block;
+ uint64_t total = 0;
+
+ QTAILQ_FOREACH(block, &ram_list.blocks, next)
+ total += block->length;
+
+ return total;
+}
+
+static void migration_end(void)
+{
+ if (migration_bitmap) {
+ memory_global_dirty_log_stop();
+ g_free(migration_bitmap);
+ migration_bitmap = NULL;
+ }
+
+ if (XBZRLE.cache) {
+ cache_fini(XBZRLE.cache);
+ g_free(XBZRLE.cache);
+ g_free(XBZRLE.encoded_buf);
+ g_free(XBZRLE.current_buf);
+ g_free(XBZRLE.decoded_buf);
+ XBZRLE.cache = NULL;
+ }
+}
+
+static void ram_migration_cancel(void *opaque)
+{
+ migration_end();
+}
+
+static void reset_ram_globals(void)
+{
+ last_seen_block = NULL;
+ last_sent_block = NULL;
+ last_offset = 0;
+ last_version = ram_list.version;
+}
+
+#define MAX_WAIT 50 /* ms, half buffered_file limit */
+
+static int ram_save_setup(QEMUFile *f, void *opaque)
+{
+ RAMBlock *block;
+ int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS;
+
+ migration_bitmap = bitmap_new(ram_pages);
+ bitmap_set(migration_bitmap, 0, ram_pages);
+ migration_dirty_pages = ram_pages;
+
+ if (migrate_use_xbzrle()) {
+ XBZRLE.cache = cache_init(migrate_xbzrle_cache_size() /
+ TARGET_PAGE_SIZE,
+ TARGET_PAGE_SIZE);
+ if (!XBZRLE.cache) {
+ DPRINTF("Error creating cache\n");
+ return -1;
+ }
+ XBZRLE.encoded_buf = g_malloc0(TARGET_PAGE_SIZE);
+ XBZRLE.current_buf = g_malloc(TARGET_PAGE_SIZE);
+ acct_clear();
+ }
+
+ qemu_mutex_lock_iothread();
+ qemu_mutex_lock_ramlist();
+ bytes_transferred = 0;
+ reset_ram_globals();
+
+ memory_global_dirty_log_start();
+ migration_bitmap_sync();
+ qemu_mutex_unlock_iothread();
+
+ qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE);
+
+ QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ qemu_put_byte(f, strlen(block->idstr));
+ qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr));
+ qemu_put_be64(f, block->length);
+ }
+
+ qemu_mutex_unlock_ramlist();
+ qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
+
+ return 0;
+}
+
+static int ram_save_iterate(QEMUFile *f, void *opaque)
+{
+ int ret;
+ int i;
+ int64_t t0;
+ int total_sent = 0;
+
+ qemu_mutex_lock_ramlist();
+
+ if (ram_list.version != last_version) {
+ reset_ram_globals();
+ }
+
+ t0 = qemu_get_clock_ns(rt_clock);
+ i = 0;
+ while ((ret = qemu_file_rate_limit(f)) == 0) {
+ int bytes_sent;
+
+ bytes_sent = ram_save_block(f, false);
+ /* no more blocks to sent */
+ if (bytes_sent == 0) {
+ break;
+ }
+ total_sent += bytes_sent;
+ acct_info.iterations++;
+ /* we want to check in the 1st loop, just in case it was the 1st time
+ and we had to sync the dirty bitmap.
+ qemu_get_clock_ns() is a bit expensive, so we only check each some
+ iterations
+ */
+ if ((i & 63) == 0) {
+ uint64_t t1 = (qemu_get_clock_ns(rt_clock) - t0) / 1000000;
+ if (t1 > MAX_WAIT) {
+ DPRINTF("big wait: %" PRIu64 " milliseconds, %d iterations\n",
+ t1, i);
+ break;
+ }
+ }
+ i++;
+ }
+
+ qemu_mutex_unlock_ramlist();
+
+ if (ret < 0) {
+ bytes_transferred += total_sent;
+ return ret;
+ }
+
+ qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
+ total_sent += 8;
+ bytes_transferred += total_sent;
+
+ return total_sent;
+}
+
+static int ram_save_complete(QEMUFile *f, void *opaque)
+{
+ qemu_mutex_lock_ramlist();
+ migration_bitmap_sync();
+
+ /* try transferring iterative blocks of memory */
+
+ /* flush all remaining blocks regardless of rate limiting */
+ while (true) {
+ int bytes_sent;
+
+ bytes_sent = ram_save_block(f, true);
+ /* no more blocks to sent */
+ if (bytes_sent == 0) {
+ break;
+ }
+ bytes_transferred += bytes_sent;
+ }
+ migration_end();
+
+ qemu_mutex_unlock_ramlist();
+ qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
+
+ return 0;
+}
+
+static uint64_t ram_save_pending(QEMUFile *f, void *opaque, uint64_t max_size)
+{
+ uint64_t remaining_size;
+
+ remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE;
+
+ if (remaining_size < max_size) {
+ qemu_mutex_lock_iothread();
+ migration_bitmap_sync();
+ qemu_mutex_unlock_iothread();
+ remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE;
+ }
+ return remaining_size;
+}
+
+static int load_xbzrle(QEMUFile *f, ram_addr_t addr, void *host)
+{
+ int ret, rc = 0;
+ unsigned int xh_len;
+ int xh_flags;
+
+ if (!XBZRLE.decoded_buf) {
+ XBZRLE.decoded_buf = g_malloc(TARGET_PAGE_SIZE);
+ }
+
+ /* extract RLE header */
+ xh_flags = qemu_get_byte(f);
+ xh_len = qemu_get_be16(f);
+
+ if (xh_flags != ENCODING_FLAG_XBZRLE) {
+ fprintf(stderr, "Failed to load XBZRLE page - wrong compression!\n");
+ return -1;
+ }
+
+ if (xh_len > TARGET_PAGE_SIZE) {
+ fprintf(stderr, "Failed to load XBZRLE page - len overflow!\n");
+ return -1;
+ }
+ /* load data and decode */
+ qemu_get_buffer(f, XBZRLE.decoded_buf, xh_len);
+
+ /* decode RLE */
+ ret = xbzrle_decode_buffer(XBZRLE.decoded_buf, xh_len, host,
+ TARGET_PAGE_SIZE);
+ if (ret == -1) {
+ fprintf(stderr, "Failed to load XBZRLE page - decode error!\n");
+ rc = -1;
+ } else if (ret > TARGET_PAGE_SIZE) {
+ fprintf(stderr, "Failed to load XBZRLE page - size %d exceeds %d!\n",
+ ret, TARGET_PAGE_SIZE);
+ abort();
+ }
+
+ return rc;
+}
+
+static inline void *host_from_stream_offset(QEMUFile *f,
+ ram_addr_t offset,
+ int flags)
+{
+ static RAMBlock *block = NULL;
+ char id[256];
+ uint8_t len;
+
+ if (flags & RAM_SAVE_FLAG_CONTINUE) {
+ if (!block) {
+ fprintf(stderr, "Ack, bad migration stream!\n");
+ return NULL;
+ }
+
+ return memory_region_get_ram_ptr(block->mr) + offset;
+ }
+
+ len = qemu_get_byte(f);
+ qemu_get_buffer(f, (uint8_t *)id, len);
+ id[len] = 0;
+
+ QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ if (!strncmp(id, block->idstr, sizeof(id)))
+ return memory_region_get_ram_ptr(block->mr) + offset;
+ }
+
+ fprintf(stderr, "Can't find block %s!\n", id);
+ return NULL;
+}
+
+static int ram_load(QEMUFile *f, void *opaque, int version_id)
+{
+ ram_addr_t addr;
+ int flags, ret = 0;
+ int error;
+ static uint64_t seq_iter;
+
+ seq_iter++;
+
+ if (version_id < 4 || version_id > 4) {
+ return -EINVAL;
+ }
+
+ do {
+ addr = qemu_get_be64(f);
+
+ flags = addr & ~TARGET_PAGE_MASK;
+ addr &= TARGET_PAGE_MASK;
+
+ if (flags & RAM_SAVE_FLAG_MEM_SIZE) {
+ if (version_id == 4) {
+ /* Synchronize RAM block list */
+ char id[256];
+ ram_addr_t length;
+ ram_addr_t total_ram_bytes = addr;
+
+ while (total_ram_bytes) {
+ RAMBlock *block;
+ uint8_t len;
+
+ len = qemu_get_byte(f);
+ qemu_get_buffer(f, (uint8_t *)id, len);
+ id[len] = 0;
+ length = qemu_get_be64(f);
+
+ QTAILQ_FOREACH(block, &ram_list.blocks, next) {
+ if (!strncmp(id, block->idstr, sizeof(id))) {
+ if (block->length != length) {
+ ret = -EINVAL;
+ goto done;
+ }
+ break;
+ }
+ }
+
+ if (!block) {
+ fprintf(stderr, "Unknown ramblock \"%s\", cannot "
+ "accept migration\n", id);
+ ret = -EINVAL;
+ goto done;
+ }
+
+ total_ram_bytes -= length;
+ }
+ }
+ }
+
+ if (flags & RAM_SAVE_FLAG_COMPRESS) {
+ void *host;
+ uint8_t ch;
+
+ host = host_from_stream_offset(f, addr, flags);
+ if (!host) {
+ return -EINVAL;
+ }
+
+ ch = qemu_get_byte(f);
+ memset(host, ch, TARGET_PAGE_SIZE);
+#ifndef _WIN32
+ if (ch == 0 &&
+ (!kvm_enabled() || kvm_has_sync_mmu()) &&
+ getpagesize() <= TARGET_PAGE_SIZE) {
+ qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED);
+ }
+#endif
+ } else if (flags & RAM_SAVE_FLAG_PAGE) {
+ void *host;
+
+ host = host_from_stream_offset(f, addr, flags);
+ if (!host) {
+ return -EINVAL;
+ }
+
+ qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
+ } else if (flags & RAM_SAVE_FLAG_XBZRLE) {
+ void *host = host_from_stream_offset(f, addr, flags);
+ if (!host) {
+ return -EINVAL;
+ }
+
+ if (load_xbzrle(f, addr, host) < 0) {
+ ret = -EINVAL;
+ goto done;
+ }
+ }
+ error = qemu_file_get_error(f);
+ if (error) {
+ ret = error;
+ goto done;
+ }
+ } while (!(flags & RAM_SAVE_FLAG_EOS));
+
+done:
+ DPRINTF("Completed load of VM with exit code %d seq iteration "
+ "%" PRIu64 "\n", ret, seq_iter);
+ return ret;
+}
+
+SaveVMHandlers savevm_ram_handlers = {
+ .save_live_setup = ram_save_setup,
+ .save_live_iterate = ram_save_iterate,
+ .save_live_complete = ram_save_complete,
+ .save_live_pending = ram_save_pending,
+ .load_state = ram_load,
+ .cancel = ram_migration_cancel,
+};
--
MST
- [Qemu-devel] [PATCHv2] migration: move ram migration support,
Michael S. Tsirkin <=