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-rw-r--r--block/backup.c150
-rw-r--r--block/io.c35
-rw-r--r--block/trace-events1
-rw-r--r--include/block/block.h5
4 files changed, 132 insertions, 59 deletions
diff --git a/block/backup.c b/block/backup.c
index d18be40caf..81895ddbe2 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -45,6 +45,8 @@ typedef struct BackupBlockJob {
QLIST_HEAD(, CowRequest) inflight_reqs;
HBitmap *copy_bitmap;
+ bool use_copy_range;
+ int64_t copy_range_size;
} BackupBlockJob;
static const BlockJobDriver backup_job_driver;
@@ -86,19 +88,101 @@ static void cow_request_end(CowRequest *req)
qemu_co_queue_restart_all(&req->wait_queue);
}
+/* Copy range to target with a bounce buffer and return the bytes copied. If
+ * error occured, 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;
+
+ 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,
+ 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;
+ }
+ goto fail;
+ }
+
+ if (qemu_iovec_is_zero(&qiov)) {
+ ret = blk_co_pwrite_zeroes(job->target, start,
+ qiov.size, BDRV_REQ_MAY_UNMAP);
+ } else {
+ ret = blk_co_pwritev(job->target, start,
+ qiov.size, &qiov,
+ 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 occured, 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;
+
+ 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,
+ is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0);
+ 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);
@@ -110,60 +194,38 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
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;
- job_progress_update(&job->common.job, n);
+ start += ret;
+ job->bytes_read += ret;
+ job_progress_update(&job->common.job, ret);
+ ret = 0;
}
-out:
if (bounce_buffer) {
qemu_vfree(bounce_buffer);
}
@@ -665,6 +727,12 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
} 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,
diff --git a/block/io.c b/block/io.c
index 7035b78a20..1a2272fad3 100644
--- a/block/io.c
+++ b/block/io.c
@@ -2897,18 +2897,11 @@ static int coroutine_fn bdrv_co_copy_range_internal(BdrvChild *src,
bool recurse_src)
{
BdrvTrackedRequest src_req, dst_req;
- BlockDriverState *src_bs = src->bs;
- BlockDriverState *dst_bs = dst->bs;
int ret;
- if (!src || !dst || !src->bs || !dst->bs) {
+ if (!dst || !dst->bs) {
return -ENOMEDIUM;
}
- ret = bdrv_check_byte_request(src->bs, src_offset, bytes);
- if (ret) {
- return ret;
- }
-
ret = bdrv_check_byte_request(dst->bs, dst_offset, bytes);
if (ret) {
return ret;
@@ -2917,20 +2910,30 @@ static int coroutine_fn bdrv_co_copy_range_internal(BdrvChild *src,
return bdrv_co_pwrite_zeroes(dst, dst_offset, bytes, flags);
}
+ if (!src || !src->bs) {
+ return -ENOMEDIUM;
+ }
+ ret = bdrv_check_byte_request(src->bs, src_offset, bytes);
+ if (ret) {
+ return ret;
+ }
+
if (!src->bs->drv->bdrv_co_copy_range_from
|| !dst->bs->drv->bdrv_co_copy_range_to
|| src->bs->encrypted || dst->bs->encrypted) {
return -ENOTSUP;
}
- bdrv_inc_in_flight(src_bs);
- bdrv_inc_in_flight(dst_bs);
- tracked_request_begin(&src_req, src_bs, src_offset,
+ bdrv_inc_in_flight(src->bs);
+ bdrv_inc_in_flight(dst->bs);
+ tracked_request_begin(&src_req, src->bs, src_offset,
bytes, BDRV_TRACKED_READ);
- tracked_request_begin(&dst_req, dst_bs, dst_offset,
+ tracked_request_begin(&dst_req, dst->bs, dst_offset,
bytes, BDRV_TRACKED_WRITE);
- wait_serialising_requests(&src_req);
- wait_serialising_requests(&dst_req);
+ if (!(flags & BDRV_REQ_NO_SERIALISING)) {
+ wait_serialising_requests(&src_req);
+ wait_serialising_requests(&dst_req);
+ }
if (recurse_src) {
ret = src->bs->drv->bdrv_co_copy_range_from(src->bs,
src, src_offset,
@@ -2944,8 +2947,8 @@ static int coroutine_fn bdrv_co_copy_range_internal(BdrvChild *src,
}
tracked_request_end(&src_req);
tracked_request_end(&dst_req);
- bdrv_dec_in_flight(src_bs);
- bdrv_dec_in_flight(dst_bs);
+ bdrv_dec_in_flight(src->bs);
+ bdrv_dec_in_flight(dst->bs);
return ret;
}
diff --git a/block/trace-events b/block/trace-events
index 2d59b53fd3..c35287b48a 100644
--- a/block/trace-events
+++ b/block/trace-events
@@ -42,6 +42,7 @@ backup_do_cow_skip(void *job, int64_t start) "job %p start %"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"
+backup_do_cow_copy_range_fail(void *job, int64_t start, int ret) "job %p start %"PRId64" ret %d"
# blockdev.c
qmp_block_job_cancel(void *job) "job %p"
diff --git a/include/block/block.h b/include/block/block.h
index 2ffc1c64c6..e5c7759a0c 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -659,13 +659,14 @@ void bdrv_unregister_buf(BlockDriverState *bs, void *host);
* @dst: Destination child to copy data to
* @dst_offset: offset in @dst image to write data
* @bytes: number of bytes to copy
- * @flags: request flags. Must be one of:
- * 0 - actually read data from src;
+ * @flags: request flags. Supported flags:
* BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero
* write on @dst as if bdrv_co_pwrite_zeroes is
* called. Used to simplify caller code, or
* during BlockDriver.bdrv_co_copy_range_from()
* recursion.
+ * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping
+ * requests currently in flight.
*
* Returns: 0 if succeeded; negative error code if failed.
**/
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-23 07:28:54 +0000