From: Samuel Just <sam.just@inktank.com>
Date: Wed, 4 Dec 2013 00:25:07 +0000 (-0800)
Subject: PGBackend,ReplicatedBackend: add support for rolling back log entries
X-Git-Tag: v0.78~286^2~28
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=155b4b069f3627098fab0922aa256c9140d3df0d;p=ceph.git

PGBackend,ReplicatedBackend: add support for rolling back log entries

Signed-off-by: Samuel Just <sam.just@inktank.com>
---

diff --git a/src/osd/Makefile.am b/src/osd/Makefile.am
index 9076062fc866..9bbc7e4616e0 100644
--- a/src/osd/Makefile.am
+++ b/src/osd/Makefile.am
@@ -10,6 +10,7 @@ libosd_la_SOURCES = \
 	osd/PGLog.cc \
 	osd/ReplicatedPG.cc \
 	osd/ReplicatedBackend.cc \
+	osd/PGBackend.cc \
 	osd/Ager.cc \
 	osd/HitSet.cc \
 	osd/OSD.cc \
diff --git a/src/osd/PGBackend.cc b/src/osd/PGBackend.cc
new file mode 100644
index 000000000000..11c29cd8733c
--- /dev/null
+++ b/src/osd/PGBackend.cc
@@ -0,0 +1,66 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2013 Inktank Storage, Inc.
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation.  See file COPYING.
+ *
+ */
+
+
+#include "PGBackend.h"
+
+// -- ObjectModDesc --
+struct RollbackVisitor : public ObjectModDesc::Visitor {
+  const hobject_t &hoid;
+  PGBackend *pg;
+  ObjectStore::Transaction t;
+  RollbackVisitor(
+    const hobject_t &hoid,
+    PGBackend *pg) : hoid(hoid), pg(pg) {}
+  void append(uint64_t old_size) {
+    ObjectStore::Transaction temp;
+    pg->rollback_append(hoid, old_size, &temp);
+    temp.append(t);
+    temp.swap(t);
+  }
+  void setattrs(map<string, boost::optional<bufferlist> > &attrs) {
+    ObjectStore::Transaction temp;
+    pg->rollback_setattrs(hoid, attrs, &temp);
+    temp.append(t);
+    temp.swap(t);
+  }
+  void rmobject(version_t old_version) {
+    ObjectStore::Transaction temp;
+    pg->rollback_unstash(hoid, old_version, &temp);
+    temp.append(t);
+    temp.swap(t);
+  }
+  void create() {
+    ObjectStore::Transaction temp;
+    pg->rollback_create(hoid, &temp);
+    temp.append(t);
+    temp.swap(t);
+  }
+  void update_snaps(set<snapid_t> &snaps) {
+    // pass
+  }
+};
+
+void PGBackend::rollback(
+  const hobject_t &hoid,
+  const ObjectModDesc &desc,
+  ObjectStore::Transaction *t)
+{
+  assert(desc.can_rollback());
+  RollbackVisitor vis(hoid, this);
+  desc.visit(&vis);
+  t->append(vis.t);
+}
+
+
diff --git a/src/osd/PGBackend.h b/src/osd/PGBackend.h
index 1d7a682fdac9..fd2339ee39b6 100644
--- a/src/osd/PGBackend.h
+++ b/src/osd/PGBackend.h
@@ -15,8 +15,13 @@
 #ifndef PGBACKEND_H
 #define PGBACKEND_H
 
+#include "OSDMap.h"
+#include "PGLog.h"
+#include "osd_types.h"
+#include "common/WorkQueue.h"
 #include "osd_types.h"
 #include "include/Context.h"
+#include "os/ObjectStore.h"
 #include <string>
 
  /**
@@ -353,6 +358,40 @@
      OpRequestRef op                      ///< [in] op
      ) = 0;
 
+
+   void rollback(
+     const hobject_t &hoid,
+     const ObjectModDesc &desc,
+     ObjectStore::Transaction *t);
+
+   /// Rollback reset attrs
+   virtual void rollback_setattrs(
+     const hobject_t &hoid,
+     map<string, boost::optional<bufferlist> > &old_attrs,
+     ObjectStore::Transaction *t) { assert(0); }
+
+   /// Rollback truncate
+   virtual void rollback_append(
+     const hobject_t &hoid,
+     uint64_t old_size,
+     ObjectStore::Transaction *t) { assert(0); }
+
+   /// Rollback unstash
+   virtual void rollback_unstash(
+     const hobject_t &hoid,
+     version_t old_version,
+     ObjectStore::Transaction *t) { assert(0); }
+
+   /// Rollback create
+   virtual void rollback_create(
+     const hobject_t &hoid,
+     ObjectStore::Transaction *t) { assert(0); }
+
+   /// Trim object stashed at stashed_version
+   virtual void trim_stashed_object(
+     const hobject_t &hoid,
+     version_t stashed_version) { assert(0); }
+
    /// List objects in collection
    virtual int objects_list_partial(
      const hobject_t &begin,
diff --git a/src/osd/ReplicatedBackend.h b/src/osd/ReplicatedBackend.h
index 166826251e34..f05147110185 100644
--- a/src/osd/ReplicatedBackend.h
+++ b/src/osd/ReplicatedBackend.h
@@ -368,6 +368,49 @@ public:
     osd_reqid_t reqid,
     OpRequestRef op
     );
+
+  void rollback_setattrs(
+    const hobject_t &hoid,
+    map<string, boost::optional<bufferlist> > &old_attrs,
+    ObjectStore::Transaction *t) {
+    map<string, bufferlist> to_set;
+    set<string> to_remove;
+    for (map<string, boost::optional<bufferlist> >::iterator i = old_attrs.begin();
+	 i != old_attrs.end();
+	 ++i) {
+      if (i->second) {
+	to_set[i->first] = i->second.get();
+      } else {
+	t->rmattr(coll, hoid, i->first);
+      }
+    }
+    t->setattrs(coll, hoid, to_set);
+  }
+
+  void rollback_append(
+    const hobject_t &hoid,
+    uint64_t old_size,
+    ObjectStore::Transaction *t) {
+    t->truncate(coll, hoid, old_size);
+  }
+
+  void rollback_unstash(
+    const hobject_t &hoid,
+    version_t old_version,
+    ObjectStore::Transaction *t) {
+    t->remove(coll, hoid);
+    t->collection_move_rename(
+      coll,
+      ghobject_t(hoid, old_version, ghobject_t::NO_SHARD),
+      coll,
+      hoid);
+  }
+
+  void rollback_create(
+    const hobject_t &hoid,
+    ObjectStore::Transaction *t) {
+    t->remove(coll, hoid);
+  }
 private:
   void issue_op(
     const hobject_t &soid,