static int push_frame(struct del_stack *s, dm_block_t b, unsigned level)
{
int r;
uint32_t ref_count;
if (s->top >= MAX_SPINE_DEPTH - 1) {
DMERR("btree deletion stack out of memory");
return -ENOMEM;
}
r = dm_tm_ref(s->tm, b, &ref_count);
if (r)
return r;
if (ref_count > 1)
/*
* This is a shared node, so we can just decrement it's
* reference counter and leave the children.
*/
dm_tm_dec(s->tm, b);
else {
uint32_t flags;
struct frame *f = s->spine + ++s->top;
r = dm_tm_read_lock(s->tm, b, &btree_node_validator, &f->b);
if (r) {
s->top--;
return r;
}
f->n = dm_block_data(f->b);
f->level = level;
f->nr_children = le32_to_cpu(f->n->header.nr_entries);
f->current_child = 0;
flags = le32_to_cpu(f->n->header.flags);
if (flags & INTERNAL_NODE || is_internal_level(s->info, f))
prefetch_children(s, f);
}
return 0;
}
static void block_dec(void *context, const void *value)
{
int r;
uint64_t b;
__le64 block_le;
uint32_t ref_count;
struct dm_block *block;
struct array_block *ab;
struct dm_array_info *info = context;
memcpy(&block_le, value, sizeof(block_le));
b = le64_to_cpu(block_le);
r = dm_tm_ref(info->btree_info.tm, b, &ref_count);
if (r) {
DMERR_LIMIT("couldn't get reference count for block %llu",
(unsigned long long) b);
return;
}
if (ref_count == 1) {
/*
* We're about to drop the last reference to this ablock.
* So we need to decrement the ref count of the contents.
*/
r = get_ablock(info, b, &block, &ab);
if (r) {
DMERR_LIMIT("couldn't get array block %llu",
(unsigned long long) b);
return;
}
dec_ablock_entries(info, ab);
unlock_ablock(info, block);
}
dm_tm_dec(info->btree_info.tm, b);
}
