@@ -104,87 +104,61 @@ static void cow_request_end(CowRequest *req)
* error occurred, return a negative error number
*
* @bounce_buffer is assumed to enough to store
- * MIN(BACKUP_MAX_BOUNCE_BUFFER, @end - @start) bytes
+ * MIN(BACKUP_MAX_BOUNCE_BUFFER, @bytes) bytes
*/
-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)
+static int coroutine_fn backup_cow_with_bounce_buffer(
+ BackupBlockJob *job, int64_t offset, int64_t bytes,
+ BdrvRequestFlags read_flags, bool *error_is_read, void *bounce_buffer)
{
- int ret;
BlockBackend *blk = job->common.blk;
- int nbytes, remaining_bytes;
- int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
-
- assert(QEMU_IS_ALIGNED(start, job->cluster_size));
- bdrv_reset_dirty_bitmap(job->copy_bitmap, start, end - start);
- nbytes = MIN(end - start, job->len - start);
-
- remaining_bytes = nbytes;
- while (remaining_bytes) {
- int chunk = MIN(BACKUP_MAX_BOUNCE_BUFFER, remaining_bytes);
+ while (bytes) {
+ int ret;
+ int chunk = MIN(BACKUP_MAX_BOUNCE_BUFFER, bytes);
- ret = blk_co_pread(blk, start, chunk, bounce_buffer, read_flags);
+ ret = blk_co_pread(blk, offset, chunk, bounce_buffer, read_flags);
if (ret < 0) {
- trace_backup_do_cow_read_fail(job, start, ret);
+ trace_backup_do_cow_read_fail(job, offset, ret);
if (error_is_read) {
*error_is_read = true;
}
- goto fail;
+ return ret;
}
- ret = blk_co_pwrite(job->target, start, chunk, bounce_buffer,
+ ret = blk_co_pwrite(job->target, offset, chunk, bounce_buffer,
job->write_flags);
if (ret < 0) {
- trace_backup_do_cow_write_fail(job, start, ret);
+ trace_backup_do_cow_write_fail(job, offset, ret);
if (error_is_read) {
*error_is_read = false;
}
- goto fail;
+ return ret;
}
- start += chunk;
- remaining_bytes -= chunk;
+ offset += chunk;
+ bytes -= chunk;
}
- return nbytes;
-fail:
- bdrv_set_dirty_bitmap(job->copy_bitmap, start, job->cluster_size);
- return ret;
-
+ return 0;
}
/* 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)
+ int64_t offset,
+ int64_t bytes,
+ BdrvRequestFlags read_flags)
{
int ret;
- int nr_clusters;
BlockBackend *blk = job->common.blk;
- int nbytes = MIN(end - start, job->len - start);
- int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
-
- assert(end - start < INT_MAX);
- assert(QEMU_IS_ALIGNED(start, job->cluster_size));
- nr_clusters = DIV_ROUND_UP(nbytes, job->cluster_size);
- bdrv_reset_dirty_bitmap(job->copy_bitmap, start,
- job->cluster_size * nr_clusters);
- ret = blk_co_copy_range(blk, start, job->target, start, nbytes,
+
+ ret = blk_co_copy_range(blk, offset, job->target, offset, bytes,
read_flags, job->write_flags);
if (ret < 0) {
- trace_backup_do_cow_copy_range_fail(job, start, ret);
- bdrv_set_dirty_bitmap(job->copy_bitmap, start,
- job->cluster_size * nr_clusters);
- return ret;
+ trace_backup_do_cow_copy_range_fail(job, offset, ret);
}
- return nbytes;
+ return ret;
}
/*
@@ -268,6 +242,8 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
int64_t start, end; /* bytes */
void *bounce_buffer = NULL;
int64_t skip_bytes;
+ BdrvRequestFlags read_flags =
+ is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
qemu_co_rwlock_rdlock(&job->flush_rwlock);
@@ -281,6 +257,7 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
while (start < end) {
int64_t dirty_end;
+ int64_t cur_bytes;
if (!bdrv_dirty_bitmap_get(job->copy_bitmap, start)) {
trace_backup_do_cow_skip(job, start);
@@ -304,10 +281,11 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
}
trace_backup_do_cow_process(job, start);
+ cur_bytes = MIN(dirty_end - start, job->len - start);
+ bdrv_reset_dirty_bitmap(job->copy_bitmap, start, dirty_end - start);
if (job->use_copy_range) {
- ret = backup_cow_with_offload(job, start, dirty_end,
- is_write_notifier);
+ ret = backup_cow_with_offload(job, start, cur_bytes, read_flags);
if (ret < 0) {
job->use_copy_range = false;
}
@@ -315,24 +293,25 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
if (!job->use_copy_range) {
if (!bounce_buffer) {
size_t len = MIN(BACKUP_MAX_BOUNCE_BUFFER,
- MAX(dirty_end - start, end - dirty_end));
+ MAX(cur_bytes,
+ end - start - cur_bytes));
bounce_buffer = blk_try_blockalign(job->common.blk, len);
}
- ret = backup_cow_with_bounce_buffer(job, start, dirty_end,
- is_write_notifier,
- error_is_read, bounce_buffer);
+ ret = backup_cow_with_bounce_buffer(job, start, cur_bytes,
+ read_flags, error_is_read,
+ bounce_buffer);
}
if (ret < 0) {
+ bdrv_set_dirty_bitmap(job->copy_bitmap, start, dirty_end - start);
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.
*/
- start += ret;
- job->bytes_read += ret;
- job_progress_update(&job->common.job, ret);
- ret = 0;
+ start += cur_bytes;
+ job->bytes_read += cur_bytes;
+ job_progress_update(&job->common.job, cur_bytes);
}
if (bounce_buffer) {