Similarly to previous commit, prepare for parallelizing write-loop
iterations.
Signed-off-by: Vladimir Sementsov-Ogievskiy
---
block/qcow2.c | 153 +-
1 file changed, 89 insertions(+), 64 deletions(-)
diff --git a/block/qcow2.c b/block/qcow2.c
index 89afb4272e..3aaa180e2b 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2234,6 +2234,87 @@ static int handle_alloc_space(BlockDriverState *bs,
QCowL2Meta *l2meta)
return 0;
}
+/*
+ * qcow2_co_pwritev_task
+ * Called with s->lock unlocked
+ * l2meta - if not NULL, qcow2_co_do_pwritev() will consume it. Caller must
not
+ * use it somehow after qcow2_co_pwritev_task() call
+ */
+static coroutine_fn int qcow2_co_pwritev_task(BlockDriverState *bs,
+ uint64_t file_cluster_offset,
+ uint64_t offset, uint64_t bytes,
+ QEMUIOVector *qiov,
+ uint64_t qiov_offset,
+ QCowL2Meta *l2meta)
+{
+int ret;
+BDRVQcow2State *s = bs->opaque;
+void *crypt_buf = NULL;
+int offset_in_cluster = offset_into_cluster(s, offset);
+QEMUIOVector encrypted_qiov;
+
+if (bs->encrypted) {
+assert(s->crypto);
+assert(bytes <= QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
+crypt_buf = qemu_try_blockalign(bs->file->bs, bytes);
+if (crypt_buf == NULL) {
+ret = -ENOMEM;
+goto out_unlocked;
+}
+qemu_iovec_to_buf(qiov, qiov_offset, crypt_buf, bytes);
+
+if (qcow2_co_encrypt(bs, file_cluster_offset, offset,
+ crypt_buf, bytes) < 0) {
+ret = -EIO;
+goto out_unlocked;
+}
+
+qemu_iovec_init_buf(&encrypted_qiov, crypt_buf, bytes);
+qiov = &encrypted_qiov;
+qiov_offset = 0;
+}
+
+/* Try to efficiently initialize the physical space with zeroes */
+ret = handle_alloc_space(bs, l2meta);
+if (ret < 0) {
+goto out_unlocked;
+}
+
+/*
+ * If we need to do COW, check if it's possible to merge the
+ * writing of the guest data together with that of the COW regions.
+ * If it's not possible (or not necessary) then write the
+ * guest data now.
+ */
+if (!merge_cow(offset, bytes, qiov, qiov_offset, l2meta)) {
+BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
+trace_qcow2_writev_data(qemu_coroutine_self(),
+file_cluster_offset + offset_in_cluster);
+ret = bdrv_co_pwritev_part(s->data_file,
+ file_cluster_offset + offset_in_cluster,
+ bytes, qiov, qiov_offset, 0);
+if (ret < 0) {
+goto out_unlocked;
+}
+}
+
+qemu_co_mutex_lock(&s->lock);
+
+ret = qcow2_handle_l2meta(bs, &l2meta, true);
+goto out_locked;
+
+out_unlocked:
+qemu_co_mutex_lock(&s->lock);
+
+out_locked:
+qcow2_handle_l2meta(bs, &l2meta, false);
+qemu_co_mutex_unlock(&s->lock);
+
+qemu_vfree(crypt_buf);
+
+return ret;
+}
+
static coroutine_fn int qcow2_co_pwritev_part(
BlockDriverState *bs, uint64_t offset, uint64_t bytes,
QEMUIOVector *qiov, size_t qiov_offset, int flags)
@@ -2243,15 +2324,10 @@ static coroutine_fn int qcow2_co_pwritev_part(
int ret;
unsigned int cur_bytes; /* number of sectors in current iteration */
uint64_t cluster_offset;
-QEMUIOVector encrypted_qiov;
-uint64_t bytes_done = 0;
-uint8_t *cluster_data = NULL;
QCowL2Meta *l2meta = NULL;
trace_qcow2_writev_start_req(qemu_coroutine_self(), offset, bytes);
-qemu_co_mutex_lock(&s->lock);
-
while (bytes != 0) {
l2meta = NULL;
@@ -2265,6 +2341,8 @@ static coroutine_fn int qcow2_co_pwritev_part(
- offset_in_cluster);
}
+qemu_co_mutex_lock(&s->lock);
+
ret = qcow2_alloc_cluster_offset(bs, offset, &cur_bytes,
&cluster_offset, &l2meta);
if (ret < 0) {
@@ -2282,73 +2360,20 @@ static coroutine_fn int qcow2_co_pwritev_part(
qemu_co_mutex_unlock(&s->lock);
-if (bs->encrypted) {
-assert(s->crypto);
-if (!cluster_data) {
-cluster_data = qemu_try_blockalign(bs->file->bs,
- QCOW_MAX_CRYPT_CLUSTERS
- * s->cluster_size);
-if (cluster_data == NULL) {
-ret = -ENOMEM;
-goto out_unlocked;
-}
-}
-
-assert(cur_bytes <= QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
-qemu_iovec_to_buf(qiov, qiov_offset + bytes_done,
- cluster_data, cur_
