ceph-immutable-object-cache: don't return empty path for older clients

They would crash. Now they will try to read a non-existing file.

Signed-off-by: Mykola Golub <mgolub@suse.com>

8 files changed, 45 insertions, 5 deletions

diff --git a/src/tools/immutable_object_cache/CacheClient.cc b/src/tools/immutable_object_cache/CacheClient.cc
index bbacf5e208f..e31713cd507 100644
--- a/src/tools/immutable_object_cache/CacheClient.cc
+++ b/src/tools/immutable_object_cache/CacheClient.cc
@@ -4,6 +4,7 @@
 #include <boost/bind/bind.hpp>
 #include "CacheClient.h"
 #include "common/Cond.h"
+#include "common/version.h"
 
 #define dout_context g_ceph_context
 #define dout_subsys ceph_subsys_immutable_obj_cache
@@ -378,7 +379,8 @@ namespace immutable_obj_cache {
   // TODO : re-implement this method
   int CacheClient::register_client(Context* on_finish) {
     ObjectCacheRequest* reg_req = new ObjectCacheRegData(RBDSC_REGISTER,
-                                                         m_sequence_id++);
+                                                         m_sequence_id++,
+                                                         ceph_version_to_str());
     reg_req->encode();
 
     bufferlist bl;
diff --git a/src/tools/immutable_object_cache/CacheController.cc b/src/tools/immutable_object_cache/CacheController.cc
index c033ca49b61..1fade8f84b4 100644
--- a/src/tools/immutable_object_cache/CacheController.cc
+++ b/src/tools/immutable_object_cache/CacheController.cc
@@ -102,6 +102,9 @@ void CacheController::handle_request(CacheSession* session,
     case RBDSC_REGISTER: {
       // TODO(dehao): skip register and allow clients to lookup directly
 
+      auto req_reg_data = reinterpret_cast <ObjectCacheRegData*> (req);
+      session->set_client_version(req_reg_data->version);
+
       ObjectCacheRequest* reply = new ObjectCacheRegReplyData(
         RBDSC_REGISTER_REPLY, req->seq);
       session->send(reply);
@@ -112,9 +115,11 @@ void CacheController::handle_request(CacheSession* session,
       std::string cache_path;
       ObjectCacheReadData* req_read_data =
         reinterpret_cast <ObjectCacheReadData*> (req);
+      bool return_dne_path = session->client_version().empty();
       int ret = m_object_cache_store->lookup_object(
         req_read_data->pool_namespace, req_read_data->pool_id,
-        req_read_data->snap_id, req_read_data->oid, cache_path);
+        req_read_data->snap_id, req_read_data->oid, return_dne_path,
+        cache_path);
       ObjectCacheRequest* reply = nullptr;
       if (ret != OBJ_CACHE_PROMOTED && ret != OBJ_CACHE_DNE) {
         reply = new ObjectCacheReadRadosData(RBDSC_READ_RADOS, req->seq);
diff --git a/src/tools/immutable_object_cache/CacheSession.cc b/src/tools/immutable_object_cache/CacheSession.cc
index 6d8daf05be1..38c38c97d44 100644
--- a/src/tools/immutable_object_cache/CacheSession.cc
+++ b/src/tools/immutable_object_cache/CacheSession.cc
@@ -32,6 +32,14 @@ stream_protocol::socket& CacheSession::socket() {
   return m_dm_socket;
 }
 
+void CacheSession::set_client_version(const std::string &version) {
+  m_client_version = version;
+}
+
+const std::string &CacheSession::client_version() const {
+  return m_client_version;
+}
+
 void CacheSession::close() {
   if (m_dm_socket.is_open()) {
     boost::system::error_code close_ec;
diff --git a/src/tools/immutable_object_cache/CacheSession.h b/src/tools/immutable_object_cache/CacheSession.h
index 3cc4d9ed800..0826e8a2b9a 100644
--- a/src/tools/immutable_object_cache/CacheSession.h
+++ b/src/tools/immutable_object_cache/CacheSession.h
@@ -35,11 +35,16 @@ class CacheSession : public std::enable_shared_from_this<CacheSession> {
   void fault(const boost::system::error_code& ec);
   void send(ObjectCacheRequest* msg);
 
+  void set_client_version(const std::string &version);
+  const std::string &client_version() const;
+
  private:
   stream_protocol::socket m_dm_socket;
   ProcessMsg m_server_process_msg;
   CephContext* m_cct;
 
+  std::string m_client_version;
+
   bufferptr m_bp_header;
 };
 
diff --git a/src/tools/immutable_object_cache/ObjectCacheStore.cc b/src/tools/immutable_object_cache/ObjectCacheStore.cc
index aec72f3aa50..a0b2b27ce16 100644
--- a/src/tools/immutable_object_cache/ObjectCacheStore.cc
+++ b/src/tools/immutable_object_cache/ObjectCacheStore.cc
@@ -181,6 +181,7 @@ int ObjectCacheStore::handle_promote_callback(int ret, bufferlist* read_buf,
 int ObjectCacheStore::lookup_object(std::string pool_nspace,
                                     uint64_t pool_id, uint64_t snap_id,
                                     std::string object_name,
+                                    bool return_dne_path,
                                     std::string& target_cache_file_path) {
   ldout(m_cct, 20) << "object name = " << object_name
                    << " in pool ID : " << pool_id << dendl;
@@ -202,6 +203,10 @@ int ObjectCacheStore::lookup_object(std::string pool_nspace,
       target_cache_file_path = get_cache_file_path(cache_file_name);
       return ret;
     case OBJ_CACHE_DNE:
+      if (return_dne_path) {
+        target_cache_file_path = get_cache_file_path(cache_file_name);
+      }
+      return ret;
     case OBJ_CACHE_SKIP:
       return ret;
     default:
diff --git a/src/tools/immutable_object_cache/ObjectCacheStore.h b/src/tools/immutable_object_cache/ObjectCacheStore.h
index eba003412e0..270a93be452 100644
--- a/src/tools/immutable_object_cache/ObjectCacheStore.h
+++ b/src/tools/immutable_object_cache/ObjectCacheStore.h
@@ -31,6 +31,7 @@ class ObjectCacheStore {
   int lookup_object(std::string pool_nspace,
                     uint64_t pool_id, uint64_t snap_id,
                     std::string object_name,
+                    bool return_dne_path,
                     std::string& target_cache_file_path);
 
  private:
diff --git a/src/tools/immutable_object_cache/Types.cc b/src/tools/immutable_object_cache/Types.cc
index a0a4c6352aa..e65e94bee1e 100644
--- a/src/tools/immutable_object_cache/Types.cc
+++ b/src/tools/immutable_object_cache/Types.cc
@@ -40,12 +40,24 @@ void ObjectCacheRequest::decode(bufferlist& bl) {
 ObjectCacheRegData::ObjectCacheRegData() {}
 ObjectCacheRegData::ObjectCacheRegData(uint16_t t, uint64_t s)
   : ObjectCacheRequest(t, s) {}
+ObjectCacheRegData::ObjectCacheRegData(uint16_t t, uint64_t s,
+                                       const std::string &version)
+  : ObjectCacheRequest(t, s),
+    version(version) {
+}
 
 ObjectCacheRegData::~ObjectCacheRegData() {}
 
-void ObjectCacheRegData::encode_payload() {}
+void ObjectCacheRegData::encode_payload() {
+  ceph::encode(version, payload);
+}
 
-void ObjectCacheRegData::decode_payload(bufferlist::const_iterator i) {}
+void ObjectCacheRegData::decode_payload(bufferlist::const_iterator i) {
+  if (i.end()) {
+    return;
+  }
+  ceph::decode(version, i);
+}
 
 ObjectCacheRegReplyData::ObjectCacheRegReplyData() {}
 ObjectCacheRegReplyData::ObjectCacheRegReplyData(uint16_t t, uint64_t s)
diff --git a/src/tools/immutable_object_cache/Types.h b/src/tools/immutable_object_cache/Types.h
index 7967d16564f..5fab1ec4897 100644
--- a/src/tools/immutable_object_cache/Types.h
+++ b/src/tools/immutable_object_cache/Types.h
@@ -57,13 +57,15 @@ class ObjectCacheRequest {
 
 class ObjectCacheRegData : public ObjectCacheRequest {
  public:
+  std::string version;
   ObjectCacheRegData();
+  ObjectCacheRegData(uint16_t t, uint64_t s, const std::string &version);
   ObjectCacheRegData(uint16_t t, uint64_t s);
   ~ObjectCacheRegData() override;
   void encode_payload() override;
   void decode_payload(bufferlist::const_iterator bl) override;
   uint16_t get_request_type() override { return RBDSC_REGISTER; }
-  bool payload_empty() override { return true; }
+  bool payload_empty() override { return false; }
 };
 
 class ObjectCacheRegReplyData : public ObjectCacheRequest {