diff options
author | Kevin Wolf <kwolf@redhat.com> | 2013-03-26 17:50:11 +0100 |
---|---|---|
committer | Stefan Hajnoczi <stefanha@redhat.com> | 2013-03-28 11:52:44 +0100 |
commit | 88c6588c5165da1526f735ed850861c5b74670bd (patch) | |
tree | 9ad34c64a0ead016b0c384a319e9721837d7f81a /block | |
parent | 710c2496d8cecc92568d439a3cf9d5874b3a55e2 (diff) | |
download | hqemu-88c6588c5165da1526f735ed850861c5b74670bd.zip hqemu-88c6588c5165da1526f735ed850861c5b74670bd.tar.gz |
qcow2: Allow requests with multiple l2metas
Instead of expecting a single l2meta, have a list of them. This allows
to still have a single I/O request for the guest data, even though
multiple l2meta may be needed in order to describe both a COW overwrite
and a new cluster allocation (typical sequential write case).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/qcow2-cluster.c | 3 | ||||
-rw-r--r-- | block/qcow2.c | 14 | ||||
-rw-r--r-- | block/qcow2.h | 3 |
3 files changed, 17 insertions, 3 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 78e7db9..6dc7f7f 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1069,10 +1069,13 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, int alloc_n_start = offset_into_cluster(s, guest_offset) >> BDRV_SECTOR_BITS; int nb_sectors = MIN(requested_sectors, avail_sectors); + QCowL2Meta *old_m = *m; *m = g_malloc0(sizeof(**m)); **m = (QCowL2Meta) { + .next = old_m, + .alloc_offset = alloc_cluster_offset, .offset = start_of_cluster(s, guest_offset), .nb_clusters = nb_clusters, diff --git a/block/qcow2.c b/block/qcow2.c index 3f7edf5..7e7d775 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -858,7 +858,9 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs, goto fail; } - if (l2meta != NULL) { + while (l2meta != NULL) { + QCowL2Meta *next; + ret = qcow2_alloc_cluster_link_l2(bs, l2meta); if (ret < 0) { goto fail; @@ -871,8 +873,9 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs, qemu_co_queue_restart_all(&l2meta->dependent_requests); + next = l2meta->next; g_free(l2meta); - l2meta = NULL; + l2meta = next; } remaining_sectors -= cur_nr_sectors; @@ -885,12 +888,17 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs, fail: qemu_co_mutex_unlock(&s->lock); - if (l2meta != NULL) { + while (l2meta != NULL) { + QCowL2Meta *next; + if (l2meta->nb_clusters != 0) { QLIST_REMOVE(l2meta, next_in_flight); } qemu_co_queue_restart_all(&l2meta->dependent_requests); + + next = l2meta->next; g_free(l2meta); + l2meta = next; } qemu_iovec_destroy(&hd_qiov); diff --git a/block/qcow2.h b/block/qcow2.h index 32806bd..bf8db2a 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -250,6 +250,9 @@ typedef struct QCowL2Meta */ Qcow2COWRegion cow_end; + /** Pointer to next L2Meta of the same write request */ + struct QCowL2Meta *next; + QLIST_ENTRY(QCowL2Meta) next_in_flight; } QCowL2Meta; |