From 83ad165be74420bc5bbf0fe4f62b6f53b1fb6004 Mon Sep 17 00:00:00 2001 From: Alberto Garcia Date: Mon, 5 Feb 2018 16:33:27 +0200 Subject: qcow2: Update qcow2_update_snapshot_refcount() to support L2 slices qcow2_update_snapshot_refcount() increases the refcount of all clusters of a given snapshot. In order to do that it needs to load all its L2 tables and iterate over their entries. Since we'll be loading L2 slices instead of full tables we need to add an extra loop that iterates over all slices of each L2 table. This function doesn't need any additional changes so apart from that this patch simply updates the variable name from l2_table to l2_slice. Signed-off-by: Alberto Garcia Message-id: 5f4db199b9637f4833b58487135124d70add8cf0.1517840877.git.berto@igalia.com Reviewed-by: Max Reitz Reviewed-by: Eric Blake Signed-off-by: Max Reitz --- block/qcow2-refcount.c | 32 ++++++++++++++++++-------------- 1 file changed, 18 insertions(+), 14 deletions(-) (limited to 'block/qcow2-refcount.c') diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index dfa28301c4..d46b69d7f3 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -1183,17 +1183,20 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, int64_t l1_table_offset, int l1_size, int addend) { BDRVQcow2State *s = bs->opaque; - uint64_t *l1_table, *l2_table, l2_offset, entry, l1_size2, refcount; + uint64_t *l1_table, *l2_slice, l2_offset, entry, l1_size2, refcount; bool l1_allocated = false; int64_t old_entry, old_l2_offset; + unsigned slice, slice_size2, n_slices; int i, j, l1_modified = 0, nb_csectors; int ret; assert(addend >= -1 && addend <= 1); - l2_table = NULL; + l2_slice = NULL; l1_table = NULL; l1_size2 = l1_size * sizeof(uint64_t); + slice_size2 = s->l2_slice_size * sizeof(uint64_t); + n_slices = s->cluster_size / slice_size2; s->cache_discards = true; @@ -1236,19 +1239,19 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, goto fail; } - { + for (slice = 0; slice < n_slices; slice++) { ret = qcow2_cache_get(bs, s->l2_table_cache, - l2_offset, - (void **) &l2_table); + l2_offset + slice * slice_size2, + (void **) &l2_slice); if (ret < 0) { goto fail; } - for (j = 0; j < s->l2_size; j++) { + for (j = 0; j < s->l2_slice_size; j++) { uint64_t cluster_index; uint64_t offset; - entry = be64_to_cpu(l2_table[j]); + entry = be64_to_cpu(l2_slice[j]); old_entry = entry; entry &= ~QCOW_OFLAG_COPIED; offset = entry & L2E_OFFSET_MASK; @@ -1273,12 +1276,14 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, case QCOW2_CLUSTER_NORMAL: case QCOW2_CLUSTER_ZERO_ALLOC: if (offset_into_cluster(s, offset)) { + /* Here l2_index means table (not slice) index */ + int l2_index = slice * s->l2_slice_size + j; qcow2_signal_corruption( bs, true, -1, -1, "Cluster " "allocation offset %#" PRIx64 " unaligned (L2 offset: %#" PRIx64 ", L2 index: %#x)", - offset, l2_offset, j); + offset, l2_offset, l2_index); ret = -EIO; goto fail; } @@ -1317,14 +1322,13 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, qcow2_cache_set_dependency(bs, s->l2_table_cache, s->refcount_block_cache); } - l2_table[j] = cpu_to_be64(entry); + l2_slice[j] = cpu_to_be64(entry); qcow2_cache_entry_mark_dirty(s->l2_table_cache, - l2_table); + l2_slice); } } - qcow2_cache_put(s->l2_table_cache, (void **) &l2_table); - + qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); } if (addend != 0) { @@ -1352,8 +1356,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, ret = bdrv_flush(bs); fail: - if (l2_table) { - qcow2_cache_put(s->l2_table_cache, (void **) &l2_table); + if (l2_slice) { + qcow2_cache_put(s->l2_table_cache, (void **) &l2_slice); } s->cache_discards = false; -- cgit v1.2.1