From c000a15fedf1a45ab920d65c4f9c2427d375347e Mon Sep 17 00:00:00 2001
From: Orit Wasserman <owasserm@redhat.com>
Date: Tue, 18 Apr 2017 12:30:07 +0300
Subject: [PATCH] rgw: Add lock/unlock bucket instance and
 block_while_resharding methods

Signed-off-by: Orit Wasserman <owasserm@redhat.com>
---
 src/rgw/rgw_reshard.cc | 68 +++++++++++++++++++++++++++++++++++++++++-
 src/rgw/rgw_reshard.h  |  5 +++-
 2 files changed, 71 insertions(+), 2 deletions(-)

diff --git a/src/rgw/rgw_reshard.cc b/src/rgw/rgw_reshard.cc
index bae28de06ba20..ab7bc8c9c038b 100644
--- a/src/rgw/rgw_reshard.cc
+++ b/src/rgw/rgw_reshard.cc
@@ -14,7 +14,8 @@ const string reshard_oid = "reshard";
 const string reshard_lock_name = "reshard_process";
 const string bucket_instance_lock_name = "bucket_instance_lock";
 
-RGWReshard::RGWReshard(CephContext *_cct, RGWRados* _store):cct(_cct), store(_store)
+RGWReshard::RGWReshard(CephContext *_cct, RGWRados* _store):cct(_cct), store(_store),
+							    instance_lock(bucket_instance_lock_name)
 {
     max_jobs = cct->_conf->rgw_reshard_max_jobs;
 }
@@ -268,3 +269,68 @@ int RGWReshard::clear_bucket_resharding(const string& bucket_instance_oid, cls_r
 }
 
 
+int RGWReshard::lock_bucket_index_shared(const string& oid)
+{
+  int ret = get_io_ctx(io_ctx);
+  if (ret < 0)
+    return ret;
+
+  ret = instance_lock.lock_shared(&io_ctx, oid);
+  if (ret == -EBUSY) {
+    dout(0) << "RGWReshardLog::add failed to acquire lock on " << reshard_oid << dendl;
+    return 0;
+  }
+
+  return ret;
+}
+
+int RGWReshard::unlock_bucket_index(const string& oid)
+{
+  int ret = get_io_ctx(io_ctx);
+  if (ret < 0)
+    return ret;
+  instance_lock.unlock(&io_ctx, oid);
+  return 0;
+}
+
+
+const int num_retries = 10;
+const int default_reshard_sleep_duration = 30;
+
+int RGWReshard::block_while_resharding(const string& bucket_instance_oid)
+{
+  int ret = 0;
+  cls_rgw_bucket_instance_entry entry;
+  bool resharding = false;
+
+  for (int i=0; i< num_retries;i++) {
+    ret = lock_bucket_index_shared(bucket_instance_oid);
+    if (ret < 0) {
+      return ret;
+    }
+
+    ret = cls_rgw_get_bucket_resharding(io_ctx, bucket_instance_oid,
+					entry, resharding);
+    if (ret < 0) {
+      ldout(cct, 0) << "RGWReshard::" << __func__ << " ERROR: failed to get bucket resharding :"  <<
+	cpp_strerror(-ret)<< dendl;
+      return ret;
+    }
+
+    if (resharding) {
+      ret = unlock_bucket_index(bucket_instance_oid);
+      if (ret < 0) {
+	return ret;
+      }
+      sleep(default_reshard_sleep_duration);
+    } else {
+      return 0;
+    }
+  }
+  ldout(cct, 0) << "RGWReshard::" << __func__ << " ERROR: bucket is still resharding, please retry" << dendl;
+  ret = unlock_bucket_index(bucket_instance_oid);
+  if (ret < 0) {
+    return ret;
+  }
+  return -EAGAIN;
+}
diff --git a/src/rgw/rgw_reshard.h b/src/rgw/rgw_reshard.h
index 9a71e30788769..ddde84635ec46 100644
--- a/src/rgw/rgw_reshard.h
+++ b/src/rgw/rgw_reshard.h
@@ -7,6 +7,7 @@
 #include <vector>
 #include "include/rados/librados.hpp"
 #include "cls/rgw/cls_rgw_types.h"
+#include "cls/lock/cls_lock_client.h"
 
 class CephContext;
 class RGWRados;
@@ -16,8 +17,11 @@ class RGWReshard {
     RGWRados *store;
     string lock_name;
     int max_jobs;
+    rados::cls::lock::Lock instance_lock;
+    librados::IoCtx io_ctx;
 
     int get_io_ctx(librados::IoCtx& io_ctx);
+
   public:
     RGWReshard(CephContext* cct, RGWRados* _store);
     int add(cls_rgw_reshard_entry& entry);
@@ -27,7 +31,6 @@ class RGWReshard {
     int list(string& marker, uint32_t max, list<cls_rgw_reshard_entry>& entries, bool& is_truncated);
     int set_bucket_resharding(const string& bucket_instance_oid, cls_rgw_reshard_entry& entry);
     int clear_bucket_resharding(const string& bucket_instance_oid, cls_rgw_reshard_entry& entry);
-    int get_bucket_instance_info(const rgw_bucket& bucket, RGWBucketInfo& bucket_info);
 };
 
 #endif
-- 
2.39.5