mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

qcow2: Update qcow2_update_snapshot_refcount() to support L2 slices

Browse Source 
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 <berto@igalia.com>
Message-id: 5f4db199b9637f4833b58487135124d70add8cf0.1517840877.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Alberto Garcia 2018-02-05 16:33:27 +02:00 committed by Max Reitz
parent ca62dd5c2b
commit 83ad165be7
1 changed files with 18 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
block/qcow2-refcount.c
View File

@ -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;