diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 3f7272441d..4aa9ea7b29 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -263,11 +263,12 @@ int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index) * */ -static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table) +static int l2_allocate(BlockDriverState *bs, int l1_index) { BDRVQcow2State *s = bs->opaque; uint64_t old_l2_offset; - uint64_t *l2_table = NULL; + uint64_t *l2_slice = NULL; + unsigned slice, slice_size2, n_slices; int64_t l2_offset; int ret; @@ -298,42 +299,45 @@ static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table) /* allocate a new entry in the l2 cache */ + slice_size2 = s->l2_slice_size * sizeof(uint64_t); + n_slices = s->cluster_size / slice_size2; + trace_qcow2_l2_allocate_get_empty(bs, l1_index); - { + for (slice = 0; slice < n_slices; slice++) { ret = qcow2_cache_get_empty(bs, s->l2_table_cache, - l2_offset, - (void **) table); + l2_offset + slice * slice_size2, + (void **) &l2_slice); if (ret < 0) { goto fail; } - l2_table = *table; - if ((old_l2_offset & L1E_OFFSET_MASK) == 0) { - /* if there was no old l2 table, clear the new table */ - memset(l2_table, 0, s->l2_size * sizeof(uint64_t)); + /* if there was no old l2 table, clear the new slice */ + memset(l2_slice, 0, slice_size2); } else { - uint64_t *old_table; + uint64_t *old_slice; + uint64_t old_l2_slice_offset = + (old_l2_offset & L1E_OFFSET_MASK) + slice * slice_size2; - /* if there was an old l2 table, read it from the disk */ + /* if there was an old l2 table, read a slice from the disk */ BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_COW_READ); - ret = qcow2_cache_get(bs, s->l2_table_cache, - old_l2_offset & L1E_OFFSET_MASK, - (void **) &old_table); + ret = qcow2_cache_get(bs, s->l2_table_cache, old_l2_slice_offset, + (void **) &old_slice); if (ret < 0) { goto fail; } - memcpy(l2_table, old_table, s->cluster_size); + memcpy(l2_slice, old_slice, slice_size2); - qcow2_cache_put(s->l2_table_cache, (void **) &old_table); + qcow2_cache_put(s->l2_table_cache, (void **) &old_slice); } - /* write the l2 table to the file */ + /* write the l2 slice to the file */ BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_WRITE); trace_qcow2_l2_allocate_write_l2(bs, l1_index); - qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table); + qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_slice); + qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); } ret = qcow2_cache_flush(bs, s->l2_table_cache); @@ -349,14 +353,13 @@ static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table) goto fail; } - *table = l2_table; trace_qcow2_l2_allocate_done(bs, l1_index, 0); return 0; fail: trace_qcow2_l2_allocate_done(bs, l1_index, ret); - if (l2_table != NULL) { - qcow2_cache_put(s->l2_table_cache, (void **) table); + if (l2_slice != NULL) { + qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); } s->l1_table[l1_index] = old_l2_offset; if (l2_offset > 0) { @@ -701,7 +704,7 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset, } } else { /* First allocate a new L2 table (and do COW if needed) */ - ret = l2_allocate(bs, l1_index, &l2_table); + ret = l2_allocate(bs, l1_index); if (ret < 0) { return ret; } @@ -711,6 +714,15 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset, qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t), QCOW2_DISCARD_OTHER); } + + /* Get the offset of the newly-allocated l2 table */ + l2_offset = s->l1_table[l1_index] & L1E_OFFSET_MASK; + assert(offset_into_cluster(s, l2_offset) == 0); + /* Load the l2 table in memory */ + ret = l2_load(bs, offset, l2_offset, &l2_table); + if (ret < 0) { + return ret; + } } /* find the cluster offset for the given disk offset */