diff options
| -rw-r--r-- | block/qcow2-cluster.c | 9 | ||||
| -rw-r--r-- | block/qcow2.c | 60 | ||||
| -rw-r--r-- | block/qcow2.h | 1 | ||||
| -rw-r--r-- | include/qemu/iov.h | 1 | ||||
| -rw-r--r-- | util/iov.c | 10 |
5 files changed, 48 insertions, 33 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 0e4524d..f09cc99 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -829,7 +829,6 @@ static int perform_cow(BlockDriverState *bs, QCowL2Meta *m) assert(start->nb_bytes <= UINT_MAX - end->nb_bytes); assert(start->nb_bytes + end->nb_bytes <= UINT_MAX - data_bytes); assert(start->offset + start->nb_bytes <= end->offset); - assert(!m->data_qiov || m->data_qiov->size == data_bytes); if ((start->nb_bytes == 0 && end->nb_bytes == 0) || m->skip_cow) { return 0; @@ -861,7 +860,11 @@ static int perform_cow(BlockDriverState *bs, QCowL2Meta *m) /* The part of the buffer where the end region is located */ end_buffer = start_buffer + buffer_size - end->nb_bytes; - qemu_iovec_init(&qiov, 2 + (m->data_qiov ? m->data_qiov->niov : 0)); + qemu_iovec_init(&qiov, 2 + (m->data_qiov ? + qemu_iovec_subvec_niov(m->data_qiov, + m->data_qiov_offset, + data_bytes) + : 0)); qemu_co_mutex_unlock(&s->lock); /* First we read the existing data from both COW regions. We @@ -904,7 +907,7 @@ static int perform_cow(BlockDriverState *bs, QCowL2Meta *m) if (start->nb_bytes) { qemu_iovec_add(&qiov, start_buffer, start->nb_bytes); } - qemu_iovec_concat(&qiov, m->data_qiov, 0, data_bytes); + qemu_iovec_concat(&qiov, m->data_qiov, m->data_qiov_offset, data_bytes); if (end->nb_bytes) { qemu_iovec_add(&qiov, end_buffer, end->nb_bytes); } diff --git a/block/qcow2.c b/block/qcow2.c index ec1fff9..0882ff6 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2103,7 +2103,8 @@ fail: /* Check if it's possible to merge a write request with the writing of * the data from the COW regions */ static bool merge_cow(uint64_t offset, unsigned bytes, - QEMUIOVector *hd_qiov, QCowL2Meta *l2meta) + QEMUIOVector *qiov, size_t qiov_offset, + QCowL2Meta *l2meta) { QCowL2Meta *m; @@ -2132,11 +2133,12 @@ static bool merge_cow(uint64_t offset, unsigned bytes, /* Make sure that adding both COW regions to the QEMUIOVector * does not exceed IOV_MAX */ - if (hd_qiov->niov > IOV_MAX - 2) { + if (qemu_iovec_subvec_niov(qiov, qiov_offset, bytes) > IOV_MAX - 2) { continue; } - m->data_qiov = hd_qiov; + m->data_qiov = qiov; + m->data_qiov_offset = qiov_offset; return true; } @@ -2218,24 +2220,22 @@ static int handle_alloc_space(BlockDriverState *bs, QCowL2Meta *l2meta) return 0; } -static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset, - uint64_t bytes, QEMUIOVector *qiov, - int flags) +static coroutine_fn int qcow2_co_pwritev_part( + BlockDriverState *bs, uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, size_t qiov_offset, int flags) { BDRVQcow2State *s = bs->opaque; int offset_in_cluster; int ret; unsigned int cur_bytes; /* number of sectors in current iteration */ uint64_t cluster_offset; - QEMUIOVector hd_qiov; + 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_iovec_init(&hd_qiov, qiov->niov); - qemu_co_mutex_lock(&s->lock); while (bytes != 0) { @@ -2268,9 +2268,6 @@ static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset, qemu_co_mutex_unlock(&s->lock); - qemu_iovec_reset(&hd_qiov); - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, cur_bytes); - if (bs->encrypted) { assert(s->crypto); if (!cluster_data) { @@ -2283,9 +2280,9 @@ static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset, } } - assert(hd_qiov.size <= - QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size); - qemu_iovec_to_buf(&hd_qiov, 0, cluster_data, hd_qiov.size); + 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, cluster_data, cur_bytes) < 0) { @@ -2293,8 +2290,7 @@ static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset, goto out_unlocked; } - qemu_iovec_reset(&hd_qiov); - qemu_iovec_add(&hd_qiov, cluster_data, cur_bytes); + qemu_iovec_init_buf(&encrypted_qiov, cluster_data, cur_bytes); } /* Try to efficiently initialize the physical space with zeroes */ @@ -2307,13 +2303,17 @@ static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset, * 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, &hd_qiov, l2meta)) { + 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(s->data_file, - cluster_offset + offset_in_cluster, - cur_bytes, &hd_qiov, 0); + 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; } @@ -2342,7 +2342,6 @@ out_locked: qemu_co_mutex_unlock(&s->lock); - qemu_iovec_destroy(&hd_qiov); qemu_vfree(cluster_data); trace_qcow2_writev_done_req(qemu_coroutine_self(), ret); @@ -4007,8 +4006,9 @@ fail: /* XXX: put compressed sectors first, then all the cluster aligned tables to avoid losing bytes in alignment */ static coroutine_fn int -qcow2_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset, - uint64_t bytes, QEMUIOVector *qiov) +qcow2_co_pwritev_compressed_part(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, size_t qiov_offset) { BDRVQcow2State *s = bs->opaque; int ret; @@ -4045,7 +4045,7 @@ qcow2_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset, /* Zero-pad last write if image size is not cluster aligned */ memset(buf + bytes, 0, s->cluster_size - bytes); } - qemu_iovec_to_buf(qiov, 0, buf, bytes); + qemu_iovec_to_buf(qiov, qiov_offset, buf, bytes); out_buf = g_malloc(s->cluster_size); @@ -4053,7 +4053,7 @@ qcow2_co_pwritev_compressed(BlockDriverState *bs, uint64_t offset, buf, s->cluster_size); if (out_len == -ENOMEM) { /* could not compress: write normal cluster */ - ret = qcow2_co_pwritev(bs, offset, bytes, qiov, 0); + ret = qcow2_co_pwritev_part(bs, offset, bytes, qiov, qiov_offset, 0); if (ret < 0) { goto fail; } @@ -4664,8 +4664,8 @@ static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, BDRVQcow2State *s = bs->opaque; BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE); - return bs->drv->bdrv_co_pwritev(bs, qcow2_vm_state_offset(s) + pos, - qiov->size, qiov, 0); + return bs->drv->bdrv_co_pwritev_part(bs, qcow2_vm_state_offset(s) + pos, + qiov->size, qiov, 0, 0); } static int qcow2_load_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, @@ -5218,7 +5218,7 @@ BlockDriver bdrv_qcow2 = { .bdrv_co_block_status = qcow2_co_block_status, .bdrv_co_preadv_part = qcow2_co_preadv_part, - .bdrv_co_pwritev = qcow2_co_pwritev, + .bdrv_co_pwritev_part = qcow2_co_pwritev_part, .bdrv_co_flush_to_os = qcow2_co_flush_to_os, .bdrv_co_pwrite_zeroes = qcow2_co_pwrite_zeroes, @@ -5226,7 +5226,7 @@ BlockDriver bdrv_qcow2 = { .bdrv_co_copy_range_from = qcow2_co_copy_range_from, .bdrv_co_copy_range_to = qcow2_co_copy_range_to, .bdrv_co_truncate = qcow2_co_truncate, - .bdrv_co_pwritev_compressed = qcow2_co_pwritev_compressed, + .bdrv_co_pwritev_compressed_part = qcow2_co_pwritev_compressed_part, .bdrv_make_empty = qcow2_make_empty, .bdrv_snapshot_create = qcow2_snapshot_create, diff --git a/block/qcow2.h b/block/qcow2.h index fc1b0d3..998bcda 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -420,6 +420,7 @@ typedef struct QCowL2Meta * from @cow_start and @cow_end into one single write operation. */ QEMUIOVector *data_qiov; + size_t data_qiov_offset; /** Pointer to next L2Meta of the same write request */ struct QCowL2Meta *next; diff --git a/include/qemu/iov.h b/include/qemu/iov.h index 29957c8..bffc151 100644 --- a/include/qemu/iov.h +++ b/include/qemu/iov.h @@ -206,6 +206,7 @@ void qemu_iovec_init_extended( void *tail_buf, size_t tail_len); void qemu_iovec_init_slice(QEMUIOVector *qiov, QEMUIOVector *source, size_t offset, size_t len); +int qemu_iovec_subvec_niov(QEMUIOVector *qiov, size_t offset, size_t len); void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len); void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t soffset, size_t sbytes); @@ -401,6 +401,16 @@ static struct iovec *qiov_slice(QEMUIOVector *qiov, return iov; } +int qemu_iovec_subvec_niov(QEMUIOVector *qiov, size_t offset, size_t len) +{ + size_t head, tail; + int niov; + + qiov_slice(qiov, offset, len, &head, &tail, &niov); + + return niov; +} + /* * Compile new iovec, combining @head_buf buffer, sub-qiov of @mid_qiov, * and @tail_buf buffer into new qiov. |