QLIST_HEAD(, CowRequest) inflight_reqs;
HBitmap *copy_bitmap;
+ bool use_copy_range;
+ int64_t copy_range_size;
+
+ bool serialize_target_writes;
} BackupBlockJob;
static const BlockJobDriver backup_job_driver;
qemu_co_queue_restart_all(&req->wait_queue);
}
+/* Copy range to target with a bounce buffer and return the bytes copied. If
+ * error occurred, return a negative error number */
+static int coroutine_fn backup_cow_with_bounce_buffer(BackupBlockJob *job,
+ int64_t start,
+ int64_t end,
+ bool is_write_notifier,
+ bool *error_is_read,
+ void **bounce_buffer)
+{
+ int ret;
+ struct iovec iov;
+ QEMUIOVector qiov;
+ BlockBackend *blk = job->common.blk;
+ int nbytes;
+ int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
+ int write_flags = job->serialize_target_writes ? BDRV_REQ_SERIALISING : 0;
+
+ hbitmap_reset(job->copy_bitmap, start / job->cluster_size, 1);
+ nbytes = MIN(job->cluster_size, job->len - start);
+ if (!*bounce_buffer) {
+ *bounce_buffer = blk_blockalign(blk, job->cluster_size);
+ }
+ iov.iov_base = *bounce_buffer;
+ iov.iov_len = nbytes;
+ qemu_iovec_init_external(&qiov, &iov, 1);
+
+ ret = blk_co_preadv(blk, start, qiov.size, &qiov, read_flags);
+ if (ret < 0) {
+ trace_backup_do_cow_read_fail(job, start, ret);
+ if (error_is_read) {
+ *error_is_read = true;
+ }
+ goto fail;
+ }
+
+ if (qemu_iovec_is_zero(&qiov)) {
+ ret = blk_co_pwrite_zeroes(job->target, start,
+ qiov.size, write_flags | BDRV_REQ_MAY_UNMAP);
+ } else {
+ ret = blk_co_pwritev(job->target, start,
+ qiov.size, &qiov, write_flags |
+ (job->compress ? BDRV_REQ_WRITE_COMPRESSED : 0));
+ }
+ if (ret < 0) {
+ trace_backup_do_cow_write_fail(job, start, ret);
+ if (error_is_read) {
+ *error_is_read = false;
+ }
+ goto fail;
+ }
+
+ return nbytes;
+fail:
+ hbitmap_set(job->copy_bitmap, start / job->cluster_size, 1);
+ return ret;
+
+}
+
+/* Copy range to target and return the bytes copied. If error occurred, return a
+ * negative error number. */
+static int coroutine_fn backup_cow_with_offload(BackupBlockJob *job,
+ int64_t start,
+ int64_t end,
+ bool is_write_notifier)
+{
+ int ret;
+ int nr_clusters;
+ BlockBackend *blk = job->common.blk;
+ int nbytes;
+ int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
+ int write_flags = job->serialize_target_writes ? BDRV_REQ_SERIALISING : 0;
+
+ assert(QEMU_IS_ALIGNED(job->copy_range_size, job->cluster_size));
+ nbytes = MIN(job->copy_range_size, end - start);
+ nr_clusters = DIV_ROUND_UP(nbytes, job->cluster_size);
+ hbitmap_reset(job->copy_bitmap, start / job->cluster_size,
+ nr_clusters);
+ ret = blk_co_copy_range(blk, start, job->target, start, nbytes,
+ read_flags, write_flags);
+ if (ret < 0) {
+ trace_backup_do_cow_copy_range_fail(job, start, ret);
+ hbitmap_set(job->copy_bitmap, start / job->cluster_size,
+ nr_clusters);
+ return ret;
+ }
+
+ return nbytes;
+}
+
static int coroutine_fn backup_do_cow(BackupBlockJob *job,
int64_t offset, uint64_t bytes,
bool *error_is_read,
bool is_write_notifier)
{
- BlockBackend *blk = job->common.blk;
CowRequest cow_request;
- struct iovec iov;
- QEMUIOVector bounce_qiov;
- void *bounce_buffer = NULL;
int ret = 0;
int64_t start, end; /* bytes */
- int n; /* bytes */
+ void *bounce_buffer = NULL;
qemu_co_rwlock_rdlock(&job->flush_rwlock);
wait_for_overlapping_requests(job, start, end);
cow_request_begin(&cow_request, job, start, end);
- for (; start < end; start += job->cluster_size) {
+ while (start < end) {
if (!hbitmap_get(job->copy_bitmap, start / job->cluster_size)) {
trace_backup_do_cow_skip(job, start);
+ start += job->cluster_size;
continue; /* already copied */
}
- hbitmap_reset(job->copy_bitmap, start / job->cluster_size, 1);
trace_backup_do_cow_process(job, start);
- n = MIN(job->cluster_size, job->len - start);
-
- if (!bounce_buffer) {
- bounce_buffer = blk_blockalign(blk, job->cluster_size);
- }
- iov.iov_base = bounce_buffer;
- iov.iov_len = n;
- qemu_iovec_init_external(&bounce_qiov, &iov, 1);
-
- ret = blk_co_preadv(blk, start, bounce_qiov.size, &bounce_qiov,
- is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0);
- if (ret < 0) {
- trace_backup_do_cow_read_fail(job, start, ret);
- if (error_is_read) {
- *error_is_read = true;
+ if (job->use_copy_range) {
+ ret = backup_cow_with_offload(job, start, end, is_write_notifier);
+ if (ret < 0) {
+ job->use_copy_range = false;
}
- hbitmap_set(job->copy_bitmap, start / job->cluster_size, 1);
- goto out;
}
-
- if (buffer_is_zero(iov.iov_base, iov.iov_len)) {
- ret = blk_co_pwrite_zeroes(job->target, start,
- bounce_qiov.size, BDRV_REQ_MAY_UNMAP);
- } else {
- ret = blk_co_pwritev(job->target, start,
- bounce_qiov.size, &bounce_qiov,
- job->compress ? BDRV_REQ_WRITE_COMPRESSED : 0);
+ if (!job->use_copy_range) {
+ ret = backup_cow_with_bounce_buffer(job, start, end, is_write_notifier,
+ error_is_read, &bounce_buffer);
}
if (ret < 0) {
- trace_backup_do_cow_write_fail(job, start, ret);
- if (error_is_read) {
- *error_is_read = false;
- }
- hbitmap_set(job->copy_bitmap, start / job->cluster_size, 1);
- goto out;
+ break;
}
/* Publish progress, guest I/O counts as progress too. Note that the
* offset field is an opaque progress value, it is not a disk offset.
*/
- job->bytes_read += n;
- block_job_progress_update(&job->common, n);
+ start += ret;
+ job->bytes_read += ret;
+ job_progress_update(&job->common.job, ret);
+ ret = 0;
}
-out:
if (bounce_buffer) {
qemu_vfree(bounce_buffer);
}
}
}
-static void backup_commit(BlockJob *job)
+static void backup_commit(Job *job)
{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
+ BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
if (s->sync_bitmap) {
backup_cleanup_sync_bitmap(s, 0);
}
}
-static void backup_abort(BlockJob *job)
+static void backup_abort(Job *job)
{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
+ BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
if (s->sync_bitmap) {
backup_cleanup_sync_bitmap(s, -1);
}
}
-static void backup_clean(BlockJob *job)
+static void backup_clean(Job *job)
{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
+ BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
assert(s->target);
blk_unref(s->target);
s->target = NULL;
}
}
-typedef struct {
- int ret;
-} BackupCompleteData;
-
-static void backup_complete(BlockJob *job, void *opaque)
-{
- BackupCompleteData *data = opaque;
-
- block_job_completed(job, data->ret);
- g_free(data);
-}
-
static bool coroutine_fn yield_and_check(BackupBlockJob *job)
{
uint64_t delay_ns;
* return. Without a yield, the VM would not reboot. */
delay_ns = block_job_ratelimit_get_delay(&job->common, job->bytes_read);
job->bytes_read = 0;
- block_job_sleep_ns(&job->common, delay_ns);
+ job_sleep_ns(&job->common.job, delay_ns);
if (job_is_cancelled(&job->common.job)) {
return true;
HBitmapIter hbi;
hbitmap_iter_init(&hbi, job->copy_bitmap, 0);
- while ((cluster = hbitmap_iter_next(&hbi)) != -1) {
+ while ((cluster = hbitmap_iter_next(&hbi, true)) != -1) {
do {
if (yield_and_check(job)) {
return 0;
bdrv_set_dirty_iter(dbi, next_cluster * job->cluster_size);
}
- /* TODO block_job_progress_set_remaining() would make more sense */
- block_job_progress_update(&job->common,
+ /* TODO job_progress_set_remaining() would make more sense */
+ job_progress_update(&job->common.job,
job->len - hbitmap_count(job->copy_bitmap) * job->cluster_size);
bdrv_dirty_iter_free(dbi);
}
-static void coroutine_fn backup_run(void *opaque)
+static int coroutine_fn backup_run(Job *job, Error **errp)
{
- BackupBlockJob *job = opaque;
- BackupCompleteData *data;
- BlockDriverState *bs = blk_bs(job->common.blk);
+ BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
+ BlockDriverState *bs = blk_bs(s->common.blk);
int64_t offset, nb_clusters;
int ret = 0;
- QLIST_INIT(&job->inflight_reqs);
- qemu_co_rwlock_init(&job->flush_rwlock);
+ QLIST_INIT(&s->inflight_reqs);
+ qemu_co_rwlock_init(&s->flush_rwlock);
- nb_clusters = DIV_ROUND_UP(job->len, job->cluster_size);
- block_job_progress_set_remaining(&job->common, job->len);
+ nb_clusters = DIV_ROUND_UP(s->len, s->cluster_size);
+ job_progress_set_remaining(job, s->len);
- job->copy_bitmap = hbitmap_alloc(nb_clusters, 0);
- if (job->sync_mode == MIRROR_SYNC_MODE_INCREMENTAL) {
- backup_incremental_init_copy_bitmap(job);
+ s->copy_bitmap = hbitmap_alloc(nb_clusters, 0);
+ if (s->sync_mode == MIRROR_SYNC_MODE_INCREMENTAL) {
+ backup_incremental_init_copy_bitmap(s);
} else {
- hbitmap_set(job->copy_bitmap, 0, nb_clusters);
+ hbitmap_set(s->copy_bitmap, 0, nb_clusters);
}
- job->before_write.notify = backup_before_write_notify;
- bdrv_add_before_write_notifier(bs, &job->before_write);
+ s->before_write.notify = backup_before_write_notify;
+ bdrv_add_before_write_notifier(bs, &s->before_write);
- if (job->sync_mode == MIRROR_SYNC_MODE_NONE) {
+ if (s->sync_mode == MIRROR_SYNC_MODE_NONE) {
/* All bits are set in copy_bitmap to allow any cluster to be copied.
* This does not actually require them to be copied. */
- while (!job_is_cancelled(&job->common.job)) {
+ while (!job_is_cancelled(job)) {
/* Yield until the job is cancelled. We just let our before_write
* notify callback service CoW requests. */
- block_job_yield(&job->common);
+ job_yield(job);
}
- } else if (job->sync_mode == MIRROR_SYNC_MODE_INCREMENTAL) {
- ret = backup_run_incremental(job);
+ } else if (s->sync_mode == MIRROR_SYNC_MODE_INCREMENTAL) {
+ ret = backup_run_incremental(s);
} else {
/* Both FULL and TOP SYNC_MODE's require copying.. */
- for (offset = 0; offset < job->len;
- offset += job->cluster_size) {
+ for (offset = 0; offset < s->len;
+ offset += s->cluster_size) {
bool error_is_read;
int alloced = 0;
- if (yield_and_check(job)) {
+ if (yield_and_check(s)) {
break;
}
- if (job->sync_mode == MIRROR_SYNC_MODE_TOP) {
+ if (s->sync_mode == MIRROR_SYNC_MODE_TOP) {
int i;
int64_t n;
/* Check to see if these blocks are already in the
* backing file. */
- for (i = 0; i < job->cluster_size;) {
+ for (i = 0; i < s->cluster_size;) {
/* bdrv_is_allocated() only returns true/false based
* on the first set of sectors it comes across that
* are are all in the same state.
* needed but at some point that is always the case. */
alloced =
bdrv_is_allocated(bs, offset + i,
- job->cluster_size - i, &n);
+ s->cluster_size - i, &n);
i += n;
if (alloced || n == 0) {
if (alloced < 0) {
ret = alloced;
} else {
- ret = backup_do_cow(job, offset, job->cluster_size,
+ ret = backup_do_cow(s, offset, s->cluster_size,
&error_is_read, false);
}
if (ret < 0) {
/* Depending on error action, fail now or retry cluster */
BlockErrorAction action =
- backup_error_action(job, error_is_read, -ret);
+ backup_error_action(s, error_is_read, -ret);
if (action == BLOCK_ERROR_ACTION_REPORT) {
break;
} else {
- offset -= job->cluster_size;
+ offset -= s->cluster_size;
continue;
}
}
}
}
- notifier_with_return_remove(&job->before_write);
+ notifier_with_return_remove(&s->before_write);
/* wait until pending backup_do_cow() calls have completed */
- qemu_co_rwlock_wrlock(&job->flush_rwlock);
- qemu_co_rwlock_unlock(&job->flush_rwlock);
- hbitmap_free(job->copy_bitmap);
+ qemu_co_rwlock_wrlock(&s->flush_rwlock);
+ qemu_co_rwlock_unlock(&s->flush_rwlock);
+ hbitmap_free(s->copy_bitmap);
- data = g_malloc(sizeof(*data));
- data->ret = ret;
- block_job_defer_to_main_loop(&job->common, backup_complete, data);
+ return ret;
}
static const BlockJobDriver backup_job_driver = {
.instance_size = sizeof(BackupBlockJob),
.job_type = JOB_TYPE_BACKUP,
.free = block_job_free,
+ .user_resume = block_job_user_resume,
+ .drain = block_job_drain,
+ .run = backup_run,
+ .commit = backup_commit,
+ .abort = backup_abort,
+ .clean = backup_clean,
},
- .start = backup_run,
- .commit = backup_commit,
- .abort = backup_abort,
- .clean = backup_clean,
.attached_aio_context = backup_attached_aio_context,
.drain = backup_drain,
};
BlockdevOnError on_target_error,
int creation_flags,
BlockCompletionFunc *cb, void *opaque,
- BlockJobTxn *txn, Error **errp)
+ JobTxn *txn, Error **errp)
{
int64_t len;
BlockDriverInfo bdi;
sync_bitmap : NULL;
job->compress = compress;
+ /* Detect image-fleecing (and similar) schemes */
+ job->serialize_target_writes = bdrv_chain_contains(target, bs);
+
/* If there is no backing file on the target, we cannot rely on COW if our
* backup cluster size is smaller than the target cluster size. Even for
* targets with a backing file, try to avoid COW if possible. */
} else {
job->cluster_size = MAX(BACKUP_CLUSTER_SIZE_DEFAULT, bdi.cluster_size);
}
+ job->use_copy_range = true;
+ job->copy_range_size = MIN_NON_ZERO(blk_get_max_transfer(job->common.blk),
+ blk_get_max_transfer(job->target));
+ job->copy_range_size = MAX(job->cluster_size,
+ QEMU_ALIGN_UP(job->copy_range_size,
+ job->cluster_size));
/* Required permissions are already taken with target's blk_new() */
block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
bdrv_reclaim_dirty_bitmap(bs, sync_bitmap, NULL);
}
if (job) {
- backup_clean(&job->common);
- block_job_early_fail(&job->common);
+ backup_clean(&job->common.job);
+ job_early_fail(&job->common.job);
}
return NULL;
projects / qemu.git / blobdiff