#include "qemu/cutils.h"
#include "sysemu/block-backend.h"
#include "qemu/bitmap.h"
+#include "qemu/error-report.h"
#define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16)
-#define SLICE_TIME 100000000ULL /* ns */
typedef struct BackupBlockJob {
BlockJob common;
/* bitmap for sync=incremental */
BdrvDirtyBitmap *sync_bitmap;
MirrorSyncMode sync_mode;
- RateLimit limit;
BlockdevOnError on_source_error;
BlockdevOnError on_target_error;
CoRwlock flush_rwlock;
- uint64_t sectors_read;
- unsigned long *done_bitmap;
+ uint64_t len;
+ uint64_t bytes_read;
int64_t cluster_size;
bool compress;
NotifierWithReturn before_write;
QLIST_HEAD(, CowRequest) inflight_reqs;
+
+ HBitmap *copy_bitmap;
} BackupBlockJob;
-/* Size of a cluster in sectors, instead of bytes. */
-static inline int64_t cluster_size_sectors(BackupBlockJob *job)
-{
- return job->cluster_size / BDRV_SECTOR_SIZE;
-}
+static const BlockJobDriver backup_job_driver;
/* See if in-flight requests overlap and wait for them to complete */
static void coroutine_fn wait_for_overlapping_requests(BackupBlockJob *job,
do {
retry = false;
QLIST_FOREACH(req, &job->inflight_reqs, list) {
- if (end > req->start && start < req->end) {
+ if (end > req->start_byte && start < req->end_byte) {
qemu_co_queue_wait(&req->wait_queue, NULL);
retry = true;
break;
/* Keep track of an in-flight request */
static void cow_request_begin(CowRequest *req, BackupBlockJob *job,
- int64_t start, int64_t end)
+ int64_t start, int64_t end)
{
- req->start = start;
- req->end = end;
+ req->start_byte = start;
+ req->end_byte = end;
qemu_co_queue_init(&req->wait_queue);
QLIST_INSERT_HEAD(&job->inflight_reqs, req, list);
}
}
static int coroutine_fn backup_do_cow(BackupBlockJob *job,
- int64_t sector_num, int nb_sectors,
+ int64_t offset, uint64_t bytes,
bool *error_is_read,
bool is_write_notifier)
{
QEMUIOVector bounce_qiov;
void *bounce_buffer = NULL;
int ret = 0;
- int64_t sectors_per_cluster = cluster_size_sectors(job);
- int64_t start, end;
- int n;
+ int64_t start, end; /* bytes */
+ int n; /* bytes */
qemu_co_rwlock_rdlock(&job->flush_rwlock);
- start = sector_num / sectors_per_cluster;
- end = DIV_ROUND_UP(sector_num + nb_sectors, sectors_per_cluster);
+ start = QEMU_ALIGN_DOWN(offset, job->cluster_size);
+ end = QEMU_ALIGN_UP(bytes + offset, job->cluster_size);
- trace_backup_do_cow_enter(job, start, sector_num, nb_sectors);
+ trace_backup_do_cow_enter(job, start, offset, bytes);
wait_for_overlapping_requests(job, start, end);
cow_request_begin(&cow_request, job, start, end);
- for (; start < end; start++) {
- if (test_bit(start, job->done_bitmap)) {
+ for (; start < end; start += job->cluster_size) {
+ if (!hbitmap_get(job->copy_bitmap, start / job->cluster_size)) {
trace_backup_do_cow_skip(job, start);
continue; /* already copied */
}
+ hbitmap_reset(job->copy_bitmap, start / job->cluster_size, 1);
trace_backup_do_cow_process(job, start);
- n = MIN(sectors_per_cluster,
- job->common.len / BDRV_SECTOR_SIZE -
- start * sectors_per_cluster);
+ 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 * BDRV_SECTOR_SIZE;
+ iov.iov_len = n;
qemu_iovec_init_external(&bounce_qiov, &iov, 1);
- ret = blk_co_preadv(blk, start * job->cluster_size,
- bounce_qiov.size, &bounce_qiov,
+ 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;
}
+ 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 * job->cluster_size,
+ ret = blk_co_pwrite_zeroes(job->target, start,
bounce_qiov.size, BDRV_REQ_MAY_UNMAP);
} else {
- ret = blk_co_pwritev(job->target, start * job->cluster_size,
+ ret = blk_co_pwritev(job->target, start,
bounce_qiov.size, &bounce_qiov,
job->compress ? BDRV_REQ_WRITE_COMPRESSED : 0);
}
if (error_is_read) {
*error_is_read = false;
}
+ hbitmap_set(job->copy_bitmap, start / job->cluster_size, 1);
goto out;
}
- set_bit(start, job->done_bitmap);
-
/* 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->sectors_read += n;
- job->common.offset += n * BDRV_SECTOR_SIZE;
+ job->bytes_read += n;
+ block_job_progress_update(&job->common, n);
}
out:
cow_request_end(&cow_request);
- trace_backup_do_cow_return(job, sector_num, nb_sectors, ret);
+ trace_backup_do_cow_return(job, offset, bytes, ret);
qemu_co_rwlock_unlock(&job->flush_rwlock);
{
BackupBlockJob *job = container_of(notifier, BackupBlockJob, before_write);
BdrvTrackedRequest *req = opaque;
- int64_t sector_num = req->offset >> BDRV_SECTOR_BITS;
- int nb_sectors = req->bytes >> BDRV_SECTOR_BITS;
assert(req->bs == blk_bs(job->common.blk));
- assert((req->offset & (BDRV_SECTOR_SIZE - 1)) == 0);
- assert((req->bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
-
- return backup_do_cow(job, sector_num, nb_sectors, NULL, true);
-}
-
-static void backup_set_speed(BlockJob *job, int64_t speed, Error **errp)
-{
- BackupBlockJob *s = container_of(job, BackupBlockJob, common);
+ assert(QEMU_IS_ALIGNED(req->offset, BDRV_SECTOR_SIZE));
+ assert(QEMU_IS_ALIGNED(req->bytes, BDRV_SECTOR_SIZE));
- if (speed < 0) {
- error_setg(errp, QERR_INVALID_PARAMETER, "speed");
- return;
- }
- ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE, SLICE_TIME);
+ return backup_do_cow(job, req->offset, req->bytes, NULL, true);
}
static void backup_cleanup_sync_bitmap(BackupBlockJob *job, int ret)
BdrvDirtyBitmap *bm;
BlockDriverState *bs = blk_bs(job->common.blk);
- if (ret < 0 || block_job_is_cancelled(&job->common)) {
+ if (ret < 0) {
/* Merge the successor back into the parent, delete nothing. */
bm = bdrv_reclaim_dirty_bitmap(bs, job->sync_bitmap, NULL);
assert(bm);
BackupBlockJob *backup_job = container_of(job, BackupBlockJob, common);
int64_t len;
- assert(job->driver->job_type == BLOCK_JOB_TYPE_BACKUP);
+ assert(block_job_driver(job) == &backup_job_driver);
if (backup_job->sync_mode != MIRROR_SYNC_MODE_NONE) {
error_setg(errp, "The backup job only supports block checkpoint in"
return;
}
- len = DIV_ROUND_UP(backup_job->common.len, backup_job->cluster_size);
- bitmap_zero(backup_job->done_bitmap, len);
+ len = DIV_ROUND_UP(backup_job->len, backup_job->cluster_size);
+ hbitmap_set(backup_job->copy_bitmap, 0, len);
}
-void backup_wait_for_overlapping_requests(BlockJob *job, int64_t sector_num,
- int nb_sectors)
+void backup_wait_for_overlapping_requests(BlockJob *job, int64_t offset,
+ uint64_t bytes)
{
BackupBlockJob *backup_job = container_of(job, BackupBlockJob, common);
- int64_t sectors_per_cluster = cluster_size_sectors(backup_job);
int64_t start, end;
- assert(job->driver->job_type == BLOCK_JOB_TYPE_BACKUP);
+ assert(block_job_driver(job) == &backup_job_driver);
- start = sector_num / sectors_per_cluster;
- end = DIV_ROUND_UP(sector_num + nb_sectors, sectors_per_cluster);
+ start = QEMU_ALIGN_DOWN(offset, backup_job->cluster_size);
+ end = QEMU_ALIGN_UP(offset + bytes, backup_job->cluster_size);
wait_for_overlapping_requests(backup_job, start, end);
}
void backup_cow_request_begin(CowRequest *req, BlockJob *job,
- int64_t sector_num,
- int nb_sectors)
+ int64_t offset, uint64_t bytes)
{
BackupBlockJob *backup_job = container_of(job, BackupBlockJob, common);
- int64_t sectors_per_cluster = cluster_size_sectors(backup_job);
int64_t start, end;
- assert(job->driver->job_type == BLOCK_JOB_TYPE_BACKUP);
+ assert(block_job_driver(job) == &backup_job_driver);
- start = sector_num / sectors_per_cluster;
- end = DIV_ROUND_UP(sector_num + nb_sectors, sectors_per_cluster);
+ start = QEMU_ALIGN_DOWN(offset, backup_job->cluster_size);
+ end = QEMU_ALIGN_UP(offset + bytes, backup_job->cluster_size);
cow_request_begin(req, backup_job, start, end);
}
static bool coroutine_fn yield_and_check(BackupBlockJob *job)
{
+ uint64_t delay_ns;
+
if (block_job_is_cancelled(&job->common)) {
return true;
}
- /* we need to yield so that bdrv_drain_all() returns.
- * (without, VM does not reboot)
- */
- if (job->common.speed) {
- uint64_t delay_ns = ratelimit_calculate_delay(&job->limit,
- job->sectors_read);
- job->sectors_read = 0;
- block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, delay_ns);
- } else {
- block_job_sleep_ns(&job->common, QEMU_CLOCK_REALTIME, 0);
- }
+ /* We need to yield even for delay_ns = 0 so that bdrv_drain_all() can
+ * 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);
if (block_job_is_cancelled(&job->common)) {
return true;
static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
{
+ int ret;
bool error_is_read;
- int ret = 0;
- int clusters_per_iter;
- uint32_t granularity;
- int64_t sector;
int64_t cluster;
- int64_t end;
- int64_t last_cluster = -1;
- int64_t sectors_per_cluster = cluster_size_sectors(job);
- BdrvDirtyBitmapIter *dbi;
+ HBitmapIter hbi;
- granularity = bdrv_dirty_bitmap_granularity(job->sync_bitmap);
- clusters_per_iter = MAX((granularity / job->cluster_size), 1);
- dbi = bdrv_dirty_iter_new(job->sync_bitmap, 0);
+ hbitmap_iter_init(&hbi, job->copy_bitmap, 0);
+ while ((cluster = hbitmap_iter_next(&hbi)) != -1) {
+ do {
+ if (yield_and_check(job)) {
+ return 0;
+ }
+ ret = backup_do_cow(job, cluster * job->cluster_size,
+ job->cluster_size, &error_is_read, false);
+ if (ret < 0 && backup_error_action(job, error_is_read, -ret) ==
+ BLOCK_ERROR_ACTION_REPORT)
+ {
+ return ret;
+ }
+ } while (ret < 0);
+ }
- /* Find the next dirty sector(s) */
- while ((sector = bdrv_dirty_iter_next(dbi)) != -1) {
- cluster = sector / sectors_per_cluster;
+ return 0;
+}
- /* Fake progress updates for any clusters we skipped */
- if (cluster != last_cluster + 1) {
- job->common.offset += ((cluster - last_cluster - 1) *
- job->cluster_size);
+/* init copy_bitmap from sync_bitmap */
+static void backup_incremental_init_copy_bitmap(BackupBlockJob *job)
+{
+ BdrvDirtyBitmapIter *dbi;
+ int64_t offset;
+ int64_t end = DIV_ROUND_UP(bdrv_dirty_bitmap_size(job->sync_bitmap),
+ job->cluster_size);
+
+ dbi = bdrv_dirty_iter_new(job->sync_bitmap);
+ while ((offset = bdrv_dirty_iter_next(dbi)) != -1) {
+ int64_t cluster = offset / job->cluster_size;
+ int64_t next_cluster;
+
+ offset += bdrv_dirty_bitmap_granularity(job->sync_bitmap);
+ if (offset >= bdrv_dirty_bitmap_size(job->sync_bitmap)) {
+ hbitmap_set(job->copy_bitmap, cluster, end - cluster);
+ break;
}
- for (end = cluster + clusters_per_iter; cluster < end; cluster++) {
- do {
- if (yield_and_check(job)) {
- goto out;
- }
- ret = backup_do_cow(job, cluster * sectors_per_cluster,
- sectors_per_cluster, &error_is_read,
- false);
- if ((ret < 0) &&
- backup_error_action(job, error_is_read, -ret) ==
- BLOCK_ERROR_ACTION_REPORT) {
- goto out;
- }
- } while (ret < 0);
+ offset = bdrv_dirty_bitmap_next_zero(job->sync_bitmap, offset);
+ if (offset == -1) {
+ hbitmap_set(job->copy_bitmap, cluster, end - cluster);
+ break;
}
- /* If the bitmap granularity is smaller than the backup granularity,
- * we need to advance the iterator pointer to the next cluster. */
- if (granularity < job->cluster_size) {
- bdrv_set_dirty_iter(dbi, cluster * sectors_per_cluster);
+ next_cluster = DIV_ROUND_UP(offset, job->cluster_size);
+ hbitmap_set(job->copy_bitmap, cluster, next_cluster - cluster);
+ if (next_cluster >= end) {
+ break;
}
- last_cluster = cluster - 1;
+ bdrv_set_dirty_iter(dbi, next_cluster * job->cluster_size);
}
- /* Play some final catchup with the progress meter */
- end = DIV_ROUND_UP(job->common.len, job->cluster_size);
- if (last_cluster + 1 < end) {
- job->common.offset += ((end - last_cluster - 1) * job->cluster_size);
- }
+ /* TODO block_job_progress_set_remaining() would make more sense */
+ block_job_progress_update(&job->common,
+ job->len - hbitmap_count(job->copy_bitmap) * job->cluster_size);
-out:
bdrv_dirty_iter_free(dbi);
- return ret;
}
static void coroutine_fn backup_run(void *opaque)
BackupBlockJob *job = opaque;
BackupCompleteData *data;
BlockDriverState *bs = blk_bs(job->common.blk);
- int64_t start, end;
- int64_t sectors_per_cluster = cluster_size_sectors(job);
+ int64_t offset, nb_clusters;
int ret = 0;
QLIST_INIT(&job->inflight_reqs);
qemu_co_rwlock_init(&job->flush_rwlock);
- start = 0;
- end = DIV_ROUND_UP(job->common.len, job->cluster_size);
+ nb_clusters = DIV_ROUND_UP(job->len, job->cluster_size);
+ block_job_progress_set_remaining(&job->common, job->len);
+
+ job->copy_bitmap = hbitmap_alloc(nb_clusters, 0);
+ if (job->sync_mode == MIRROR_SYNC_MODE_INCREMENTAL) {
+ backup_incremental_init_copy_bitmap(job);
+ } else {
+ hbitmap_set(job->copy_bitmap, 0, nb_clusters);
+ }
- job->done_bitmap = bitmap_new(end);
job->before_write.notify = backup_before_write_notify;
bdrv_add_before_write_notifier(bs, &job->before_write);
if (job->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 (!block_job_is_cancelled(&job->common)) {
/* Yield until the job is cancelled. We just let our before_write
* notify callback service CoW requests. */
ret = backup_run_incremental(job);
} else {
/* Both FULL and TOP SYNC_MODE's require copying.. */
- for (; start < end; start++) {
+ for (offset = 0; offset < job->len;
+ offset += job->cluster_size) {
bool error_is_read;
+ int alloced = 0;
+
if (yield_and_check(job)) {
break;
}
if (job->sync_mode == MIRROR_SYNC_MODE_TOP) {
- int i, n;
- int alloced = 0;
+ int i;
+ int64_t n;
/* Check to see if these blocks are already in the
* backing file. */
- for (i = 0; i < sectors_per_cluster;) {
+ for (i = 0; i < job->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.
* backup cluster length. We end up copying more than
* needed but at some point that is always the case. */
alloced =
- bdrv_is_allocated(bs,
- start * sectors_per_cluster + i,
- sectors_per_cluster - i, &n);
+ bdrv_is_allocated(bs, offset + i,
+ job->cluster_size - i, &n);
i += n;
- if (alloced == 1 || n == 0) {
+ if (alloced || n == 0) {
break;
}
}
}
}
/* FULL sync mode we copy the whole drive. */
- ret = backup_do_cow(job, start * sectors_per_cluster,
- sectors_per_cluster, &error_is_read, false);
+ if (alloced < 0) {
+ ret = alloced;
+ } else {
+ ret = backup_do_cow(job, offset, job->cluster_size,
+ &error_is_read, false);
+ }
if (ret < 0) {
/* Depending on error action, fail now or retry cluster */
BlockErrorAction action =
if (action == BLOCK_ERROR_ACTION_REPORT) {
break;
} else {
- start--;
+ offset -= job->cluster_size;
continue;
}
}
/* wait until pending backup_do_cow() calls have completed */
qemu_co_rwlock_wrlock(&job->flush_rwlock);
qemu_co_rwlock_unlock(&job->flush_rwlock);
- g_free(job->done_bitmap);
+ hbitmap_free(job->copy_bitmap);
data = g_malloc(sizeof(*data));
data->ret = ret;
}
static const BlockJobDriver backup_job_driver = {
- .instance_size = sizeof(BackupBlockJob),
- .job_type = BLOCK_JOB_TYPE_BACKUP,
+ .job_driver = {
+ .instance_size = sizeof(BackupBlockJob),
+ },
+ .job_type = JOB_TYPE_BACKUP,
.start = backup_run,
- .set_speed = backup_set_speed,
.commit = backup_commit,
.abort = backup_abort,
.clean = backup_clean,
error_setg(errp,
"a sync_bitmap was provided to backup_run, "
"but received an incompatible sync_mode (%s)",
- MirrorSyncMode_lookup[sync_mode]);
+ MirrorSyncMode_str(sync_mode));
return NULL;
}
goto error;
}
- /* job->common.len is fixed, so we can't allow resize */
- job = block_job_create(job_id, &backup_job_driver, bs,
+ /* job->len is fixed, so we can't allow resize */
+ job = block_job_create(job_id, &backup_job_driver, txn, bs,
BLK_PERM_CONSISTENT_READ,
BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE |
BLK_PERM_WRITE_UNCHANGED | BLK_PERM_GRAPH_MOD,
* backup cluster size is smaller than the target cluster size. Even for
* targets with a backing file, try to avoid COW if possible. */
ret = bdrv_get_info(target, &bdi);
- if (ret < 0 && !target->backing) {
+ if (ret == -ENOTSUP && !target->backing) {
+ /* Cluster size is not defined */
+ warn_report("The target block device doesn't provide "
+ "information about the block size and it doesn't have a "
+ "backing file. The default block size of %u bytes is "
+ "used. If the actual block size of the target exceeds "
+ "this default, the backup may be unusable",
+ BACKUP_CLUSTER_SIZE_DEFAULT);
+ job->cluster_size = BACKUP_CLUSTER_SIZE_DEFAULT;
+ } else if (ret < 0 && !target->backing) {
error_setg_errno(errp, -ret,
"Couldn't determine the cluster size of the target image, "
"which has no backing file");
/* Required permissions are already taken with target's blk_new() */
block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
&error_abort);
- job->common.len = len;
- block_job_txn_add_job(txn, &job->common);
+ job->len = len;
return &job->common;
}
if (job) {
backup_clean(&job->common);
- block_job_unref(&job->common);
+ block_job_early_fail(&job->common);
}
return NULL;
projects / qemu.git / blobdiff