@@ -19,8 +19,8 @@
#include "qemu/co-shared-resource.h"
typedef struct BlockCopyInFlightReq {
- int64_t start_byte;
- int64_t end_byte;
+ int64_t start;
+ int64_t bytes;
QLIST_ENTRY(BlockCopyInFlightReq) list;
CoQueue wait_queue; /* coroutines blocked on this request */
} BlockCopyInFlightReq;
@@ -26,12 +26,12 @@
static BlockCopyInFlightReq *block_copy_find_inflight_req(BlockCopyState *s,
int64_t start,
- int64_t end)
+ int64_t bytes)
{
BlockCopyInFlightReq *req;
QLIST_FOREACH(req, &s->inflight_reqs, list) {
- if (end > req->start_byte && start < req->end_byte) {
+ if (start + bytes > req->start && start < req->start + req->bytes) {
return req;
}
}
@@ -41,21 +41,21 @@ static BlockCopyInFlightReq *block_copy_find_inflight_req(BlockCopyState *s,
static void coroutine_fn block_copy_wait_inflight_reqs(BlockCopyState *s,
int64_t start,
- int64_t end)
+ int64_t bytes)
{
BlockCopyInFlightReq *req;
- while ((req = block_copy_find_inflight_req(s, start, end))) {
+ while ((req = block_copy_find_inflight_req(s, start, bytes))) {
qemu_co_queue_wait(&req->wait_queue, NULL);
}
}
static void block_copy_inflight_req_begin(BlockCopyState *s,
BlockCopyInFlightReq *req,
- int64_t start, int64_t end)
+ int64_t start, int64_t bytes)
{
- req->start_byte = start;
- req->end_byte = end;
+ req->start = start;
+ req->bytes = bytes;
qemu_co_queue_init(&req->wait_queue);
QLIST_INSERT_HEAD(&s->inflight_reqs, req, list);
}
@@ -150,24 +150,26 @@ void block_copy_set_callbacks(
/*
* block_copy_do_copy
*
- * Do copy of cluser-aligned chunk. @end is allowed to exceed s->len only to
- * cover last cluster when s->len is not aligned to clusters.
+ * Do copy of cluser-aligned chunk. Requested region is allowed to exceed s->len
+ * only to cover last cluster when s->len is not aligned to clusters.
*
* No sync here: nor bitmap neighter intersecting requests handling, only copy.
*
* Returns 0 on success.
*/
static int coroutine_fn block_copy_do_copy(BlockCopyState *s,
- int64_t start, int64_t end,
+ int64_t start, int64_t bytes,
bool zeroes, bool *error_is_read)
{
int ret;
- int nbytes = MIN(end, s->len) - start;
+ int nbytes = MIN(start + bytes, s->len) - start;
void *bounce_buffer = NULL;
+ assert(start >= 0 && bytes > 0 && INT64_MAX - start >= bytes);
assert(QEMU_IS_ALIGNED(start, s->cluster_size));
- assert(QEMU_IS_ALIGNED(end, s->cluster_size));
- assert(end < s->len || end == QEMU_ALIGN_UP(s->len, s->cluster_size));
+ assert(QEMU_IS_ALIGNED(bytes, s->cluster_size));
+ assert(start + bytes <= s->len ||
+ start + bytes == QEMU_ALIGN_UP(s->len, s->cluster_size));
if (zeroes) {
ret = bdrv_co_pwrite_zeroes(s->target, start, nbytes, s->write_flags &
@@ -347,7 +349,6 @@ int coroutine_fn block_copy(BlockCopyState *s,
bool *error_is_read)
{
int ret = 0;
- int64_t end = bytes + start; /* bytes */
BlockCopyInFlightReq req;
/*
@@ -358,58 +359,59 @@ int coroutine_fn block_copy(BlockCopyState *s,
bdrv_get_aio_context(s->target->bs));
assert(QEMU_IS_ALIGNED(start, s->cluster_size));
- assert(QEMU_IS_ALIGNED(end, s->cluster_size));
+ assert(QEMU_IS_ALIGNED(bytes, s->cluster_size));
block_copy_wait_inflight_reqs(s, start, bytes);
- block_copy_inflight_req_begin(s, &req, start, end);
+ block_copy_inflight_req_begin(s, &req, start, bytes);
- while (start < end) {
- int64_t next_zero, chunk_end, status_bytes;
+ while (bytes) {
+ int64_t next_zero, cur_bytes, status_bytes;
if (!bdrv_dirty_bitmap_get(s->copy_bitmap, start)) {
trace_block_copy_skip(s, start);
start += s->cluster_size;
+ bytes -= s->cluster_size;
continue; /* already copied */
}
- chunk_end = MIN(end, start + s->copy_size);
+ cur_bytes = MIN(bytes, s->copy_size);
next_zero = bdrv_dirty_bitmap_next_zero(s->copy_bitmap, start,
- chunk_end - start);
+ cur_bytes);
if (next_zero >= 0) {
assert(next_zero > start); /* start is dirty */
- assert(next_zero < chunk_end); /* no need to do MIN() */
- chunk_end = next_zero;
+ assert(next_zero < start + cur_bytes); /* no need to do MIN() */
+ cur_bytes = next_zero - start;
}
- ret = block_copy_block_status(s, start, chunk_end - start,
- &status_bytes);
+ ret = block_copy_block_status(s, start, cur_bytes, &status_bytes);
if (s->skip_unallocated && !(ret & BDRV_BLOCK_ALLOCATED)) {
bdrv_reset_dirty_bitmap(s->copy_bitmap, start, status_bytes);
s->progress_reset_callback(s->progress_opaque);
trace_block_copy_skip_range(s, start, status_bytes);
start += status_bytes;
+ bytes -= status_bytes;
continue;
}
- chunk_end = MIN(chunk_end, start + status_bytes);
+ cur_bytes = MIN(cur_bytes, status_bytes);
trace_block_copy_process(s, start);
- bdrv_reset_dirty_bitmap(s->copy_bitmap, start, chunk_end - start);
+ bdrv_reset_dirty_bitmap(s->copy_bitmap, start, cur_bytes);
- co_get_from_shres(s->mem, chunk_end - start);
- ret = block_copy_do_copy(s, start, chunk_end, ret & BDRV_BLOCK_ZERO,
+ co_get_from_shres(s->mem, cur_bytes);
+ ret = block_copy_do_copy(s, start, cur_bytes, ret & BDRV_BLOCK_ZERO,
error_is_read);
- co_put_to_shres(s->mem, chunk_end - start);
+ co_put_to_shres(s->mem, cur_bytes);
if (ret < 0) {
- bdrv_set_dirty_bitmap(s->copy_bitmap, start, chunk_end - start);
+ bdrv_set_dirty_bitmap(s->copy_bitmap, start, cur_bytes);
break;
}
- s->progress_bytes_callback(chunk_end - start, s->progress_opaque);
- start = chunk_end;
- ret = 0;
+ s->progress_bytes_callback(cur_bytes, s->progress_opaque);
+ start += cur_bytes;
+ bytes -= cur_bytes;
}
block_copy_inflight_req_end(&req);
We have a lot of "chunk_end - start" invocations, let's switch to bytes/cur_bytes scheme instead. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> --- include/block/block-copy.h | 4 +-- block/block-copy.c | 68 ++++++++++++++++++++------------------ 2 files changed, 37 insertions(+), 35 deletions(-)