diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/backup.c | 79 | ||||
| -rw-r--r-- | block/trace-events | 1 |
2 files changed, 71 insertions, 9 deletions
diff --git a/block/backup.c b/block/backup.c index f6bf32c..9e1382e 100644 --- a/block/backup.c +++ b/block/backup.c @@ -58,6 +58,7 @@ typedef struct BackupBlockJob { int64_t copy_range_size; bool serialize_target_writes; + bool initializing_bitmap; } BackupBlockJob; static const BlockJobDriver backup_job_driver; @@ -227,6 +228,35 @@ static int backup_is_cluster_allocated(BackupBlockJob *s, int64_t offset, } } +/** + * Reset bits in copy_bitmap starting at offset if they represent unallocated + * data in the image. May reset subsequent contiguous bits. + * @return 0 when the cluster at @offset was unallocated, + * 1 otherwise, and -ret on error. + */ +static int64_t backup_bitmap_reset_unallocated(BackupBlockJob *s, + int64_t offset, int64_t *count) +{ + int ret; + int64_t clusters, bytes, estimate; + + ret = backup_is_cluster_allocated(s, offset, &clusters); + if (ret < 0) { + return ret; + } + + bytes = clusters * s->cluster_size; + + if (!ret) { + bdrv_reset_dirty_bitmap(s->copy_bitmap, offset, bytes); + estimate = bdrv_get_dirty_count(s->copy_bitmap); + job_progress_set_remaining(&s->common.job, estimate); + } + + *count = bytes; + return ret; +} + static int coroutine_fn backup_do_cow(BackupBlockJob *job, int64_t offset, uint64_t bytes, bool *error_is_read, @@ -236,6 +266,7 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job, int ret = 0; int64_t start, end; /* bytes */ void *bounce_buffer = NULL; + int64_t status_bytes; qemu_co_rwlock_rdlock(&job->flush_rwlock); @@ -262,6 +293,17 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job, dirty_end = end; } + if (job->initializing_bitmap) { + ret = backup_bitmap_reset_unallocated(job, start, &status_bytes); + if (ret == 0) { + trace_backup_do_cow_skip_range(job, start, status_bytes); + start += status_bytes; + continue; + } + /* Clamp to known allocated region */ + dirty_end = MIN(dirty_end, start + status_bytes); + } + trace_backup_do_cow_process(job, start); if (job->use_copy_range) { @@ -446,18 +488,9 @@ static int coroutine_fn backup_loop(BackupBlockJob *job) int64_t offset; BdrvDirtyBitmapIter *bdbi; int ret = 0; - int64_t dummy; bdbi = bdrv_dirty_iter_new(job->copy_bitmap); while ((offset = bdrv_dirty_iter_next(bdbi)) != -1) { - if (job->sync_mode == MIRROR_SYNC_MODE_TOP && - !backup_is_cluster_allocated(job, offset, &dummy)) - { - bdrv_reset_dirty_bitmap(job->copy_bitmap, offset, - job->cluster_size); - continue; - } - do { if (yield_and_check(job)) { goto out; @@ -488,6 +521,13 @@ static void backup_init_copy_bitmap(BackupBlockJob *job) NULL, true); assert(ret); } else { + if (job->sync_mode == MIRROR_SYNC_MODE_TOP) { + /* + * We can't hog the coroutine to initialize this thoroughly. + * Set a flag and resume work when we are able to yield safely. + */ + job->initializing_bitmap = true; + } bdrv_set_dirty_bitmap(job->copy_bitmap, 0, job->len); } @@ -509,6 +549,26 @@ static int coroutine_fn backup_run(Job *job, Error **errp) s->before_write.notify = backup_before_write_notify; bdrv_add_before_write_notifier(bs, &s->before_write); + if (s->sync_mode == MIRROR_SYNC_MODE_TOP) { + int64_t offset = 0; + int64_t count; + + for (offset = 0; offset < s->len; ) { + if (yield_and_check(s)) { + ret = -ECANCELED; + goto out; + } + + ret = backup_bitmap_reset_unallocated(s, offset, &count); + if (ret < 0) { + goto out; + } + + offset += count; + } + s->initializing_bitmap = false; + } + 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. */ @@ -521,6 +581,7 @@ static int coroutine_fn backup_run(Job *job, Error **errp) ret = backup_loop(s); } + out: notifier_with_return_remove(&s->before_write); /* wait until pending backup_do_cow() calls have completed */ diff --git a/block/trace-events b/block/trace-events index d724df0..04209f0 100644 --- a/block/trace-events +++ b/block/trace-events @@ -41,6 +41,7 @@ mirror_yield_in_flight(void *s, int64_t offset, int in_flight) "s %p offset %" P backup_do_cow_enter(void *job, int64_t start, int64_t offset, uint64_t bytes) "job %p start %" PRId64 " offset %" PRId64 " bytes %" PRIu64 backup_do_cow_return(void *job, int64_t offset, uint64_t bytes, int ret) "job %p offset %" PRId64 " bytes %" PRIu64 " ret %d" backup_do_cow_skip(void *job, int64_t start) "job %p start %"PRId64 +backup_do_cow_skip_range(void *job, int64_t start, uint64_t bytes) "job %p start %"PRId64" bytes %"PRId64 backup_do_cow_process(void *job, int64_t start) "job %p start %"PRId64 backup_do_cow_read_fail(void *job, int64_t start, int ret) "job %p start %"PRId64" ret %d" backup_do_cow_write_fail(void *job, int64_t start, int ret) "job %p start %"PRId64" ret %d" |