diff options
Diffstat (limited to 'block/qcow2.c')
| -rw-r--r-- | block/qcow2.c | 154 |
1 files changed, 90 insertions, 64 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 6feb169f7c..164b22e4a2 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2242,6 +2242,88 @@ 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_pwritev_task() 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_in_cluster, + 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) @@ -2251,15 +2333,10 @@ 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; @@ -2273,6 +2350,8 @@ 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) { @@ -2290,73 +2369,20 @@ 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_bytes); - - if (qcow2_co_encrypt(bs, cluster_offset + offset_in_cluster, offset, - cluster_data, cur_bytes) < 0) { - ret = -EIO; - goto out_unlocked; - } - - qemu_iovec_init_buf(&encrypted_qiov, cluster_data, cur_bytes); - } - - /* Try to efficiently initialize the physical space with zeroes */ - ret = handle_alloc_space(bs, l2meta); + ret = qcow2_co_pwritev_task(bs, cluster_offset, offset, cur_bytes, + qiov, qiov_offset, l2meta); + l2meta = NULL; /* l2meta is consumed by qcow2_co_pwritev_task() */ 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, cur_bytes, - bs->encrypted ? &encrypted_qiov : qiov, - bs->encrypted ? 0 : qiov_offset + bytes_done, l2meta)) - { - BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO); - trace_qcow2_writev_data(qemu_coroutine_self(), - cluster_offset + offset_in_cluster); - ret = bdrv_co_pwritev_part( - s->data_file, cluster_offset + offset_in_cluster, cur_bytes, - bs->encrypted ? &encrypted_qiov : qiov, - bs->encrypted ? 0 : qiov_offset + bytes_done, 0); - if (ret < 0) { - goto out_unlocked; - } - } - - qemu_co_mutex_lock(&s->lock); - - ret = qcow2_handle_l2meta(bs, &l2meta, true); - if (ret) { - goto out_locked; + goto fail_nometa; } bytes -= cur_bytes; offset += cur_bytes; - bytes_done += cur_bytes; + qiov_offset += cur_bytes; trace_qcow2_writev_done_part(qemu_coroutine_self(), cur_bytes); } ret = 0; - goto out_locked; -out_unlocked: qemu_co_mutex_lock(&s->lock); out_locked: @@ -2364,7 +2390,7 @@ out_locked: qemu_co_mutex_unlock(&s->lock); - qemu_vfree(cluster_data); +fail_nometa: trace_qcow2_writev_done_req(qemu_coroutine_self(), ret); return ret; |