--- /dev/null
+/*
+ * Image mirroring
+ *
+ * Copyright Red Hat, Inc. 2012
+ *
+ * Authors:
+ * Paolo Bonzini <pbonzini@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "trace.h"
+#include "block/blockjob.h"
+#include "block/block_int.h"
+#include "qapi/qmp/qerror.h"
+#include "qemu/ratelimit.h"
+#include "qemu/bitmap.h"
+
+#define SLICE_TIME 100000000ULL /* ns */
+#define MAX_IN_FLIGHT 16
+#define DEFAULT_MIRROR_BUF_SIZE (10 << 20)
+
+/* The mirroring buffer is a list of granularity-sized chunks.
+ * Free chunks are organized in a list.
+ */
+typedef struct MirrorBuffer {
+ QSIMPLEQ_ENTRY(MirrorBuffer) next;
+} MirrorBuffer;
+
+typedef struct MirrorBlockJob {
+ BlockJob common;
+ RateLimit limit;
+ BlockDriverState *target;
+ BlockDriverState *base;
+ /* The name of the graph node to replace */
+ char *replaces;
+ /* The BDS to replace */
+ BlockDriverState *to_replace;
+ /* Used to block operations on the drive-mirror-replace target */
+ Error *replace_blocker;
+ bool is_none_mode;
+ BlockdevOnError on_source_error, on_target_error;
+ bool synced;
+ bool should_complete;
+ int64_t sector_num;
+ int64_t granularity;
+ size_t buf_size;
+ int64_t bdev_length;
+ unsigned long *cow_bitmap;
+ BdrvDirtyBitmap *dirty_bitmap;
+ HBitmapIter hbi;
+ uint8_t *buf;
+ QSIMPLEQ_HEAD(, MirrorBuffer) buf_free;
+ int buf_free_count;
+
+ unsigned long *in_flight_bitmap;
+ int in_flight;
+ int sectors_in_flight;
+ int ret;
+ bool unmap;
+} MirrorBlockJob;
+
+typedef struct MirrorOp {
+ MirrorBlockJob *s;
+ QEMUIOVector qiov;
+ int64_t sector_num;
+ int nb_sectors;
+} MirrorOp;
+
+static BlockErrorAction mirror_error_action(MirrorBlockJob *s, bool read,
+ int error)
+{
+ s->synced = false;
+ if (read) {
+ return block_job_error_action(&s->common, s->common.bs,
+ s->on_source_error, true, error);
+ } else {
+ return block_job_error_action(&s->common, s->target,
+ s->on_target_error, false, error);
+ }
+}
+
+static void mirror_iteration_done(MirrorOp *op, int ret)
+{
+ MirrorBlockJob *s = op->s;
+ struct iovec *iov;
+ int64_t chunk_num;
+ int i, nb_chunks, sectors_per_chunk;
+
+ trace_mirror_iteration_done(s, op->sector_num, op->nb_sectors, ret);
+
+ s->in_flight--;
+ s->sectors_in_flight -= op->nb_sectors;
+ iov = op->qiov.iov;
+ for (i = 0; i < op->qiov.niov; i++) {
+ MirrorBuffer *buf = (MirrorBuffer *) iov[i].iov_base;
+ QSIMPLEQ_INSERT_TAIL(&s->buf_free, buf, next);
+ s->buf_free_count++;
+ }
+
+ sectors_per_chunk = s->granularity >> BDRV_SECTOR_BITS;
+ chunk_num = op->sector_num / sectors_per_chunk;
+ nb_chunks = op->nb_sectors / sectors_per_chunk;
+ bitmap_clear(s->in_flight_bitmap, chunk_num, nb_chunks);
+ if (ret >= 0) {
+ if (s->cow_bitmap) {
+ bitmap_set(s->cow_bitmap, chunk_num, nb_chunks);
+ }
+ s->common.offset += (uint64_t)op->nb_sectors * BDRV_SECTOR_SIZE;
+ }
+
+ qemu_iovec_destroy(&op->qiov);
+ g_slice_free(MirrorOp, op);
+
+ /* Enter coroutine when it is not sleeping. The coroutine sleeps to
+ * rate-limit itself. The coroutine will eventually resume since there is
+ * a sleep timeout so don't wake it early.
+ */
+ if (s->common.busy) {
+ qemu_coroutine_enter(s->common.co, NULL);
+ }
+}
+
+static void mirror_write_complete(void *opaque, int ret)
+{
+ MirrorOp *op = opaque;
+ MirrorBlockJob *s = op->s;
+ if (ret < 0) {
+ BlockErrorAction action;
+
+ bdrv_set_dirty_bitmap(s->dirty_bitmap, op->sector_num, op->nb_sectors);
+ action = mirror_error_action(s, false, -ret);
+ if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
+ s->ret = ret;
+ }
+ }
+ mirror_iteration_done(op, ret);
+}
+
+static void mirror_read_complete(void *opaque, int ret)
+{
+ MirrorOp *op = opaque;
+ MirrorBlockJob *s = op->s;
+ if (ret < 0) {
+ BlockErrorAction action;
+
+ bdrv_set_dirty_bitmap(s->dirty_bitmap, op->sector_num, op->nb_sectors);
+ action = mirror_error_action(s, true, -ret);
+ if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
+ s->ret = ret;
+ }
+
+ mirror_iteration_done(op, ret);
+ return;
+ }
+ bdrv_aio_writev(s->target, op->sector_num, &op->qiov, op->nb_sectors,
+ mirror_write_complete, op);
+}
+
+static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
+{
+ BlockDriverState *source = s->common.bs;
+ int nb_sectors, sectors_per_chunk, nb_chunks;
+ int64_t end, sector_num, next_chunk, next_sector, hbitmap_next_sector;
+ uint64_t delay_ns = 0;
+ MirrorOp *op;
+ int pnum;
+ int64_t ret;
+
+ s->sector_num = hbitmap_iter_next(&s->hbi);
+ if (s->sector_num < 0) {
+ bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi);
+ s->sector_num = hbitmap_iter_next(&s->hbi);
+ trace_mirror_restart_iter(s, bdrv_get_dirty_count(s->dirty_bitmap));
+ assert(s->sector_num >= 0);
+ }
+
+ hbitmap_next_sector = s->sector_num;
+ sector_num = s->sector_num;
+ sectors_per_chunk = s->granularity >> BDRV_SECTOR_BITS;
+ end = s->bdev_length / BDRV_SECTOR_SIZE;
+
+ /* Extend the QEMUIOVector to include all adjacent blocks that will
+ * be copied in this operation.
+ *
+ * We have to do this if we have no backing file yet in the destination,
+ * and the cluster size is very large. Then we need to do COW ourselves.
+ * The first time a cluster is copied, copy it entirely. Note that,
+ * because both the granularity and the cluster size are powers of two,
+ * the number of sectors to copy cannot exceed one cluster.
+ *
+ * We also want to extend the QEMUIOVector to include more adjacent
+ * dirty blocks if possible, to limit the number of I/O operations and
+ * run efficiently even with a small granularity.
+ */
+ nb_chunks = 0;
+ nb_sectors = 0;
+ next_sector = sector_num;
+ next_chunk = sector_num / sectors_per_chunk;
+
+ /* Wait for I/O to this cluster (from a previous iteration) to be done. */
+ while (test_bit(next_chunk, s->in_flight_bitmap)) {
+ trace_mirror_yield_in_flight(s, sector_num, s->in_flight);
+ qemu_coroutine_yield();
+ }
+
+ do {
+ int added_sectors, added_chunks;
+
+ if (!bdrv_get_dirty(source, s->dirty_bitmap, next_sector) ||
+ test_bit(next_chunk, s->in_flight_bitmap)) {
+ assert(nb_sectors > 0);
+ break;
+ }
+
+ added_sectors = sectors_per_chunk;
+ if (s->cow_bitmap && !test_bit(next_chunk, s->cow_bitmap)) {
+ bdrv_round_to_clusters(s->target,
+ next_sector, added_sectors,
+ &next_sector, &added_sectors);
+
+ /* On the first iteration, the rounding may make us copy
+ * sectors before the first dirty one.
+ */
+ if (next_sector < sector_num) {
+ assert(nb_sectors == 0);
+ sector_num = next_sector;
+ next_chunk = next_sector / sectors_per_chunk;
+ }
+ }
+
+ added_sectors = MIN(added_sectors, end - (sector_num + nb_sectors));
+ added_chunks = (added_sectors + sectors_per_chunk - 1) / sectors_per_chunk;
+
+ /* When doing COW, it may happen that there is not enough space for
+ * a full cluster. Wait if that is the case.
+ */
+ while (nb_chunks == 0 && s->buf_free_count < added_chunks) {
+ trace_mirror_yield_buf_busy(s, nb_chunks, s->in_flight);
+ qemu_coroutine_yield();
+ }
+ if (s->buf_free_count < nb_chunks + added_chunks) {
+ trace_mirror_break_buf_busy(s, nb_chunks, s->in_flight);
+ break;
+ }
+
+ /* We have enough free space to copy these sectors. */
+ bitmap_set(s->in_flight_bitmap, next_chunk, added_chunks);
+
+ nb_sectors += added_sectors;
+ nb_chunks += added_chunks;
+ next_sector += added_sectors;
+ next_chunk += added_chunks;
+ if (!s->synced && s->common.speed) {
+ delay_ns = ratelimit_calculate_delay(&s->limit, added_sectors);
+ }
+ } while (delay_ns == 0 && next_sector < end);
+
+ /* Allocate a MirrorOp that is used as an AIO callback. */
+ op = g_slice_new(MirrorOp);
+ op->s = s;
+ op->sector_num = sector_num;
+ op->nb_sectors = nb_sectors;
+
+ /* Now make a QEMUIOVector taking enough granularity-sized chunks
+ * from s->buf_free.
+ */
+ qemu_iovec_init(&op->qiov, nb_chunks);
+ next_sector = sector_num;
+ while (nb_chunks-- > 0) {
+ MirrorBuffer *buf = QSIMPLEQ_FIRST(&s->buf_free);
+ size_t remaining = (nb_sectors * BDRV_SECTOR_SIZE) - op->qiov.size;
+
+ QSIMPLEQ_REMOVE_HEAD(&s->buf_free, next);
+ s->buf_free_count--;
+ qemu_iovec_add(&op->qiov, buf, MIN(s->granularity, remaining));
+
+ /* Advance the HBitmapIter in parallel, so that we do not examine
+ * the same sector twice.
+ */
+ if (next_sector > hbitmap_next_sector
+ && bdrv_get_dirty(source, s->dirty_bitmap, next_sector)) {
+ hbitmap_next_sector = hbitmap_iter_next(&s->hbi);
+ }
+
+ next_sector += sectors_per_chunk;
+ }
+
+ bdrv_reset_dirty_bitmap(s->dirty_bitmap, sector_num, nb_sectors);
+
+ /* Copy the dirty cluster. */
+ s->in_flight++;
+ s->sectors_in_flight += nb_sectors;
+ trace_mirror_one_iteration(s, sector_num, nb_sectors);
+
+ ret = bdrv_get_block_status_above(source, NULL, sector_num,
+ nb_sectors, &pnum);
+ if (ret < 0 || pnum < nb_sectors ||
+ (ret & BDRV_BLOCK_DATA && !(ret & BDRV_BLOCK_ZERO))) {
+ bdrv_aio_readv(source, sector_num, &op->qiov, nb_sectors,
+ mirror_read_complete, op);
+ } else if (ret & BDRV_BLOCK_ZERO) {
+ bdrv_aio_write_zeroes(s->target, sector_num, op->nb_sectors,
+ s->unmap ? BDRV_REQ_MAY_UNMAP : 0,
+ mirror_write_complete, op);
+ } else {
+ assert(!(ret & BDRV_BLOCK_DATA));
+ bdrv_aio_discard(s->target, sector_num, op->nb_sectors,
+ mirror_write_complete, op);
+ }
+ return delay_ns;
+}
+
+static void mirror_free_init(MirrorBlockJob *s)
+{
+ int granularity = s->granularity;
+ size_t buf_size = s->buf_size;
+ uint8_t *buf = s->buf;
+
+ assert(s->buf_free_count == 0);
+ QSIMPLEQ_INIT(&s->buf_free);
+ while (buf_size != 0) {
+ MirrorBuffer *cur = (MirrorBuffer *)buf;
+ QSIMPLEQ_INSERT_TAIL(&s->buf_free, cur, next);
+ s->buf_free_count++;
+ buf_size -= granularity;
+ buf += granularity;
+ }
+}
+
+static void mirror_drain(MirrorBlockJob *s)
+{
+ while (s->in_flight > 0) {
+ qemu_coroutine_yield();
+ }
+}
+
+typedef struct {
+ int ret;
+} MirrorExitData;
+
+static void mirror_exit(BlockJob *job, void *opaque)
+{
+ MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
+ MirrorExitData *data = opaque;
+ AioContext *replace_aio_context = NULL;
+
+ if (s->to_replace) {
+ replace_aio_context = bdrv_get_aio_context(s->to_replace);
+ aio_context_acquire(replace_aio_context);
+ }
+
+ if (s->should_complete && data->ret == 0) {
+ BlockDriverState *to_replace = s->common.bs;
+ if (s->to_replace) {
+ to_replace = s->to_replace;
+ }
+ if (bdrv_get_flags(s->target) != bdrv_get_flags(to_replace)) {
+ bdrv_reopen(s->target, bdrv_get_flags(to_replace), NULL);
+ }
+ bdrv_swap(s->target, to_replace);
+ if (s->common.driver->job_type == BLOCK_JOB_TYPE_COMMIT) {
+ /* drop the bs loop chain formed by the swap: break the loop then
+ * trigger the unref from the top one */
+ BlockDriverState *p = s->base->backing_hd;
+ bdrv_set_backing_hd(s->base, NULL);
+ bdrv_unref(p);
+ }
+ }
+ if (s->to_replace) {
+ bdrv_op_unblock_all(s->to_replace, s->replace_blocker);
+ error_free(s->replace_blocker);
+ bdrv_unref(s->to_replace);
+ }
+ if (replace_aio_context) {
+ aio_context_release(replace_aio_context);
+ }
+ g_free(s->replaces);
+ bdrv_unref(s->target);
+ block_job_completed(&s->common, data->ret);
+ g_free(data);
+}
+
+static void coroutine_fn mirror_run(void *opaque)
+{
+ MirrorBlockJob *s = opaque;
+ MirrorExitData *data;
+ BlockDriverState *bs = s->common.bs;
+ int64_t sector_num, end, length;
+ uint64_t last_pause_ns;
+ BlockDriverInfo bdi;
+ char backing_filename[2]; /* we only need 2 characters because we are only
+ checking for a NULL string */
+ int ret = 0;
+ int n;
+
+ if (block_job_is_cancelled(&s->common)) {
+ goto immediate_exit;
+ }
+
+ s->bdev_length = bdrv_getlength(bs);
+ if (s->bdev_length < 0) {
+ ret = s->bdev_length;
+ goto immediate_exit;
+ } else if (s->bdev_length == 0) {
+ /* Report BLOCK_JOB_READY and wait for complete. */
+ block_job_event_ready(&s->common);
+ s->synced = true;
+ while (!block_job_is_cancelled(&s->common) && !s->should_complete) {
+ block_job_yield(&s->common);
+ }
+ s->common.cancelled = false;
+ goto immediate_exit;
+ }
+
+ length = DIV_ROUND_UP(s->bdev_length, s->granularity);
+ s->in_flight_bitmap = bitmap_new(length);
+
+ /* If we have no backing file yet in the destination, we cannot let
+ * the destination do COW. Instead, we copy sectors around the
+ * dirty data if needed. We need a bitmap to do that.
+ */
+ bdrv_get_backing_filename(s->target, backing_filename,
+ sizeof(backing_filename));
+ if (backing_filename[0] && !s->target->backing_hd) {
+ ret = bdrv_get_info(s->target, &bdi);
+ if (ret < 0) {
+ goto immediate_exit;
+ }
+ if (s->granularity < bdi.cluster_size) {
+ s->buf_size = MAX(s->buf_size, bdi.cluster_size);
+ s->cow_bitmap = bitmap_new(length);
+ }
+ }
+
+ end = s->bdev_length / BDRV_SECTOR_SIZE;
+ s->buf = qemu_try_blockalign(bs, s->buf_size);
+ if (s->buf == NULL) {
+ ret = -ENOMEM;
+ goto immediate_exit;
+ }
+
+ mirror_free_init(s);
+
+ last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+ if (!s->is_none_mode) {
+ /* First part, loop on the sectors and initialize the dirty bitmap. */
+ BlockDriverState *base = s->base;
+ for (sector_num = 0; sector_num < end; ) {
+ /* Just to make sure we are not exceeding int limit. */
+ int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS,
+ end - sector_num);
+ int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+
+ if (now - last_pause_ns > SLICE_TIME) {
+ last_pause_ns = now;
+ block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0);
+ }
+
+ if (block_job_is_cancelled(&s->common)) {
+ goto immediate_exit;
+ }
+
+ ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n);
+
+ if (ret < 0) {
+ goto immediate_exit;
+ }
+
+ assert(n > 0);
+ if (ret == 1) {
+ bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n);
+ }
+ sector_num += n;
+ }
+ }
+
+ bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi);
+ for (;;) {
+ uint64_t delay_ns = 0;
+ int64_t cnt;
+ bool should_complete;
+
+ if (s->ret < 0) {
+ ret = s->ret;
+ goto immediate_exit;
+ }
+
+ cnt = bdrv_get_dirty_count(s->dirty_bitmap);
+ /* s->common.offset contains the number of bytes already processed so
+ * far, cnt is the number of dirty sectors remaining and
+ * s->sectors_in_flight is the number of sectors currently being
+ * processed; together those are the current total operation length */
+ s->common.len = s->common.offset +
+ (cnt + s->sectors_in_flight) * BDRV_SECTOR_SIZE;
+
+ /* Note that even when no rate limit is applied we need to yield
+ * periodically with no pending I/O so that bdrv_drain_all() returns.
+ * We do so every SLICE_TIME nanoseconds, or when there is an error,
+ * or when the source is clean, whichever comes first.
+ */
+ if (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - last_pause_ns < SLICE_TIME &&
+ s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
+ if (s->in_flight == MAX_IN_FLIGHT || s->buf_free_count == 0 ||
+ (cnt == 0 && s->in_flight > 0)) {
+ trace_mirror_yield(s, s->in_flight, s->buf_free_count, cnt);
+ qemu_coroutine_yield();
+ continue;
+ } else if (cnt != 0) {
+ delay_ns = mirror_iteration(s);
+ }
+ }
+
+ should_complete = false;
+ if (s->in_flight == 0 && cnt == 0) {
+ trace_mirror_before_flush(s);
+ ret = bdrv_flush(s->target);
+ if (ret < 0) {
+ if (mirror_error_action(s, false, -ret) ==
+ BLOCK_ERROR_ACTION_REPORT) {
+ goto immediate_exit;
+ }
+ } else {
+ /* We're out of the streaming phase. From now on, if the job
+ * is cancelled we will actually complete all pending I/O and
+ * report completion. This way, block-job-cancel will leave
+ * the target in a consistent state.
+ */
+ if (!s->synced) {
+ block_job_event_ready(&s->common);
+ s->synced = true;
+ }
+
+ should_complete = s->should_complete ||
+ block_job_is_cancelled(&s->common);
+ cnt = bdrv_get_dirty_count(s->dirty_bitmap);
+ }
+ }
+
+ if (cnt == 0 && should_complete) {
+ /* The dirty bitmap is not updated while operations are pending.
+ * If we're about to exit, wait for pending operations before
+ * calling bdrv_get_dirty_count(bs), or we may exit while the
+ * source has dirty data to copy!
+ *
+ * Note that I/O can be submitted by the guest while
+ * mirror_populate runs.
+ */
+ trace_mirror_before_drain(s, cnt);
+ bdrv_drain(bs);
+ cnt = bdrv_get_dirty_count(s->dirty_bitmap);
+ }
+
+ ret = 0;
+ trace_mirror_before_sleep(s, cnt, s->synced, delay_ns);
+ if (!s->synced) {
+ block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
+ if (block_job_is_cancelled(&s->common)) {
+ break;
+ }
+ } else if (!should_complete) {
+ delay_ns = (s->in_flight == 0 && cnt == 0 ? SLICE_TIME : 0);
+ block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
+ } else if (cnt == 0) {
+ /* The two disks are in sync. Exit and report successful
+ * completion.
+ */
+ assert(QLIST_EMPTY(&bs->tracked_requests));
+ s->common.cancelled = false;
+ break;
+ }
+ last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+ }
+
+immediate_exit:
+ if (s->in_flight > 0) {
+ /* We get here only if something went wrong. Either the job failed,
+ * or it was cancelled prematurely so that we do not guarantee that
+ * the target is a copy of the source.
+ */
+ assert(ret < 0 || (!s->synced && block_job_is_cancelled(&s->common)));
+ mirror_drain(s);
+ }
+
+ assert(s->in_flight == 0);
+ qemu_vfree(s->buf);
+ g_free(s->cow_bitmap);
+ g_free(s->in_flight_bitmap);
+ bdrv_release_dirty_bitmap(bs, s->dirty_bitmap);
+ bdrv_iostatus_disable(s->target);
+
+ data = g_malloc(sizeof(*data));
+ data->ret = ret;
+ block_job_defer_to_main_loop(&s->common, mirror_exit, data);
+}
+
+static void mirror_set_speed(BlockJob *job, int64_t speed, Error **errp)
+{
+ MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
+
+ if (speed < 0) {
+ error_setg(errp, QERR_INVALID_PARAMETER, "speed");
+ return;
+ }
+ ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE, SLICE_TIME);
+}
+
+static void mirror_iostatus_reset(BlockJob *job)
+{
+ MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
+
+ bdrv_iostatus_reset(s->target);
+}
+
+static void mirror_complete(BlockJob *job, Error **errp)
+{
+ MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
+ Error *local_err = NULL;
+ int ret;
+
+ ret = bdrv_open_backing_file(s->target, NULL, &local_err);
+ if (ret < 0) {
+ error_propagate(errp, local_err);
+ return;
+ }
+ if (!s->synced) {
+ error_setg(errp, QERR_BLOCK_JOB_NOT_READY,
+ bdrv_get_device_name(job->bs));
+ return;
+ }
+
+ /* check the target bs is not blocked and block all operations on it */
+ if (s->replaces) {
+ AioContext *replace_aio_context;
+
+ s->to_replace = check_to_replace_node(s->replaces, &local_err);
+ if (!s->to_replace) {
+ error_propagate(errp, local_err);
+ return;
+ }
+
+ replace_aio_context = bdrv_get_aio_context(s->to_replace);
+ aio_context_acquire(replace_aio_context);
+
+ error_setg(&s->replace_blocker,
+ "block device is in use by block-job-complete");
+ bdrv_op_block_all(s->to_replace, s->replace_blocker);
+ bdrv_ref(s->to_replace);
+
+ aio_context_release(replace_aio_context);
+ }
+
+ s->should_complete = true;
+ block_job_enter(&s->common);
+}
+
+static const BlockJobDriver mirror_job_driver = {
+ .instance_size = sizeof(MirrorBlockJob),
+ .job_type = BLOCK_JOB_TYPE_MIRROR,
+ .set_speed = mirror_set_speed,
+ .iostatus_reset= mirror_iostatus_reset,
+ .complete = mirror_complete,
+};
+
+static const BlockJobDriver commit_active_job_driver = {
+ .instance_size = sizeof(MirrorBlockJob),
+ .job_type = BLOCK_JOB_TYPE_COMMIT,
+ .set_speed = mirror_set_speed,
+ .iostatus_reset
+ = mirror_iostatus_reset,
+ .complete = mirror_complete,
+};
+
+static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
+ const char *replaces,
+ int64_t speed, uint32_t granularity,
+ int64_t buf_size,
+ BlockdevOnError on_source_error,
+ BlockdevOnError on_target_error,
+ bool unmap,
+ BlockCompletionFunc *cb,
+ void *opaque, Error **errp,
+ const BlockJobDriver *driver,
+ bool is_none_mode, BlockDriverState *base)
+{
+ MirrorBlockJob *s;
+
+ if (granularity == 0) {
+ granularity = bdrv_get_default_bitmap_granularity(target);
+ }
+
+ assert ((granularity & (granularity - 1)) == 0);
+
+ if ((on_source_error == BLOCKDEV_ON_ERROR_STOP ||
+ on_source_error == BLOCKDEV_ON_ERROR_ENOSPC) &&
+ !bdrv_iostatus_is_enabled(bs)) {
+ error_setg(errp, QERR_INVALID_PARAMETER, "on-source-error");
+ return;
+ }
+
+ if (buf_size < 0) {
+ error_setg(errp, "Invalid parameter 'buf-size'");
+ return;
+ }
+
+ if (buf_size == 0) {
+ buf_size = DEFAULT_MIRROR_BUF_SIZE;
+ }
+
+ s = block_job_create(driver, bs, speed, cb, opaque, errp);
+ if (!s) {
+ return;
+ }
+
+ s->replaces = g_strdup(replaces);
+ s->on_source_error = on_source_error;
+ s->on_target_error = on_target_error;
+ s->target = target;
+ s->is_none_mode = is_none_mode;
+ s->base = base;
+ s->granularity = granularity;
+ s->buf_size = ROUND_UP(buf_size, granularity);
+ s->unmap = unmap;
+
+ s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp);
+ if (!s->dirty_bitmap) {
+ g_free(s->replaces);
+ block_job_release(bs);
+ return;
+ }
+ bdrv_set_enable_write_cache(s->target, true);
+ bdrv_set_on_error(s->target, on_target_error, on_target_error);
+ bdrv_iostatus_enable(s->target);
+ s->common.co = qemu_coroutine_create(mirror_run);
+ trace_mirror_start(bs, s, s->common.co, opaque);
+ qemu_coroutine_enter(s->common.co, s);
+}
+
+void mirror_start(BlockDriverState *bs, BlockDriverState *target,
+ const char *replaces,
+ int64_t speed, uint32_t granularity, int64_t buf_size,
+ MirrorSyncMode mode, BlockdevOnError on_source_error,
+ BlockdevOnError on_target_error,
+ bool unmap,
+ BlockCompletionFunc *cb,
+ void *opaque, Error **errp)
+{
+ bool is_none_mode;
+ BlockDriverState *base;
+
+ if (mode == MIRROR_SYNC_MODE_INCREMENTAL) {
+ error_setg(errp, "Sync mode 'incremental' not supported");
+ return;
+ }
+ is_none_mode = mode == MIRROR_SYNC_MODE_NONE;
+ base = mode == MIRROR_SYNC_MODE_TOP ? bs->backing_hd : NULL;
+ mirror_start_job(bs, target, replaces,
+ speed, granularity, buf_size,
+ on_source_error, on_target_error, unmap, cb, opaque, errp,
+ &mirror_job_driver, is_none_mode, base);
+}
+
+void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
+ int64_t speed,
+ BlockdevOnError on_error,
+ BlockCompletionFunc *cb,
+ void *opaque, Error **errp)
+{
+ int64_t length, base_length;
+ int orig_base_flags;
+ int ret;
+ Error *local_err = NULL;
+
+ orig_base_flags = bdrv_get_flags(base);
+
+ if (bdrv_reopen(base, bs->open_flags, errp)) {
+ return;
+ }
+
+ length = bdrv_getlength(bs);
+ if (length < 0) {
+ error_setg_errno(errp, -length,
+ "Unable to determine length of %s", bs->filename);
+ goto error_restore_flags;
+ }
+
+ base_length = bdrv_getlength(base);
+ if (base_length < 0) {
+ error_setg_errno(errp, -base_length,
+ "Unable to determine length of %s", base->filename);
+ goto error_restore_flags;
+ }
+
+ if (length > base_length) {
+ ret = bdrv_truncate(base, length);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret,
+ "Top image %s is larger than base image %s, and "
+ "resize of base image failed",
+ bs->filename, base->filename);
+ goto error_restore_flags;
+ }
+ }
+
+ bdrv_ref(base);
+ mirror_start_job(bs, base, NULL, speed, 0, 0,
+ on_error, on_error, false, cb, opaque, &local_err,
+ &commit_active_job_driver, false, base);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ goto error_restore_flags;
+ }
+
+ return;
+
+error_restore_flags:
+ /* ignore error and errp for bdrv_reopen, because we want to propagate
+ * the original error */
+ bdrv_reopen(base, orig_base_flags, NULL);
+ return;
+}
Code Review / kvmfornfv.git / blobdiff