[KVPOOL]decode save kvcache (#5168)

### What this PR does / why we need it?

kvpool decode save kvcache
now only support mla

### Does this PR introduce _any_ user-facing change?

### How was this patch tested?

- vLLM version: v0.12.0
- vLLM main:
ad32e3e19c

---------

Signed-off-by: baxingpiaochong <771405853@qq.com>
Co-authored-by: Chao Lei <leichao139636@163.com>

vllm_ascend/distributed/kvpool/config_data.py

@@ -87,12 +87,14 @@ class LayerPoolKey(PoolKey):
 
 class ChunkedTokenDatabase():
 
-    def __init__(self, metadata: KeyMetadata, block_size: int, use_mla: bool):
+    def __init__(self, metadata: KeyMetadata, block_size: int, use_mla: bool,
+                 partitions: Optional[List[int]]):
         self.metadata = metadata
         self.block_size = block_size
         self.use_mla = use_mla
         self.kv_caches_base_addr: list[int] = []
         self.block_len: list[int] = []
+        self.partitions = partitions
 
     def _make_key_by_hash(self,
                           chunk_hash: str,
@@ -188,6 +190,28 @@ class ChunkedTokenDatabase():
             else:
                 yield start_idx, end_idx, self._make_key_by_hash(hash_val)
 
+    def decode_adaptor_prefill_pp(self, key, addr, size):
+        if self.partitions is None or len(self.partitions) == 1:
+            return key, addr, size
+
+        new_key = []
+        new_addr = []
+        new_size = []
+
+        for i, (addr_list, size_list) in enumerate(zip(addr, size)):
+            start = 0
+            for j, part in enumerate(self.partitions):
+                # part * 2 because addr and size contain both k and v
+                end = len(addr_list) if j == len(
+                    self.partitions) - 1 else start + part * 2
+                new_str = key[i].replace(  # type: ignore[attr-defined]
+                    "@pp_rank:0", f"@pp_rank:{j}", 1)
+                new_key.append(new_str)
+                new_addr.append(addr_list[start:end])
+                new_size.append(size_list[start:end])
+                start = end
+        return new_key, new_addr, new_size
+
 
 #Parameters related to the connector metadata
 @dataclass
@@ -247,15 +271,12 @@ class RequestTracker:
 
     def update(
         self,
-        new_token_ids: list[int],
         new_block_ids: Union[tuple[list[int], ...], list[int]],
     ) -> None:
         """Update the request tracker when a running request is
         scheduled again
         """
 
-        self.token_len = self.token_len + len(new_token_ids)
-
         if len(new_block_ids) == 0:
             new_block_ids = []
         elif isinstance(new_block_ids, tuple):
@@ -378,4 +399,4 @@ class LasyerMultiBlockReqMeta:
     block_ids: list[int]
     layer_id: int
     is_last_chunk: Optional[bool] = True
-    current_event: Optional[torch.npu.Event] = None
+    current_event: Optional[torch.npu.Event] = None