initial code repo

[stor4nfv.git] / src / ceph / src / librbd / managed_lock / AcquireRequest.cc

diff --git a/src/ceph/src/librbd/managed_lock/AcquireRequest.cc b/src/ceph/src/librbd/managed_lock/AcquireRequest.cc
new file mode 100644 (file)
index 0000000..83f5dba
--- /dev/null
+++ b/src/ceph/src/librbd/managed_lock/AcquireRequest.cc
@@ -0,0 +1,181 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/managed_lock/AcquireRequest.h"
+#include "librbd/Watcher.h"
+#include "cls/lock/cls_lock_client.h"
+#include "cls/lock/cls_lock_types.h"
+#include "common/dout.h"
+#include "common/errno.h"
+#include "common/WorkQueue.h"
+#include "include/stringify.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/Utils.h"
+#include "librbd/managed_lock/BreakRequest.h"
+#include "librbd/managed_lock/GetLockerRequest.h"
+#include "librbd/managed_lock/Utils.h"
+
+#define dout_subsys ceph_subsys_rbd
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::managed_lock::AcquireRequest: " << this \
+                           << " " << __func__ << ": "
+
+using std::string;
+
+namespace librbd {
+
+using librbd::util::detail::C_AsyncCallback;
+using librbd::util::create_context_callback;
+using librbd::util::create_rados_callback;
+
+namespace managed_lock {
+
+template <typename I>
+AcquireRequest<I>* AcquireRequest<I>::create(librados::IoCtx& ioctx,
+                                             Watcher *watcher,
+                                             ContextWQ *work_queue,
+                                             const string& oid,
+                                             const string& cookie,
+                                             bool exclusive,
+                                            bool blacklist_on_break_lock,
+                                            uint32_t blacklist_expire_seconds,
+                                             Context *on_finish) {
+    return new AcquireRequest(ioctx, watcher, work_queue, oid, cookie,
+                              exclusive, blacklist_on_break_lock,
+                              blacklist_expire_seconds, on_finish);
+}
+
+template <typename I>
+AcquireRequest<I>::AcquireRequest(librados::IoCtx& ioctx, Watcher *watcher,
+                                  ContextWQ *work_queue, const string& oid,
+                                  const string& cookie, bool exclusive,
+                                  bool blacklist_on_break_lock,
+                                  uint32_t blacklist_expire_seconds,
+                                  Context *on_finish)
+  : m_ioctx(ioctx), m_watcher(watcher),
+    m_cct(reinterpret_cast<CephContext *>(m_ioctx.cct())),
+    m_work_queue(work_queue), m_oid(oid), m_cookie(cookie),
+    m_exclusive(exclusive),
+    m_blacklist_on_break_lock(blacklist_on_break_lock),
+    m_blacklist_expire_seconds(blacklist_expire_seconds),
+    m_on_finish(new C_AsyncCallback<ContextWQ>(work_queue, on_finish)) {
+}
+
+template <typename I>
+AcquireRequest<I>::~AcquireRequest() {
+}
+
+template <typename I>
+void AcquireRequest<I>::send() {
+  send_get_locker();
+}
+
+template <typename I>
+void AcquireRequest<I>::send_get_locker() {
+  ldout(m_cct, 10) << dendl;
+
+  Context *ctx = create_context_callback<
+    AcquireRequest<I>, &AcquireRequest<I>::handle_get_locker>(this);
+  auto req = GetLockerRequest<I>::create(m_ioctx, m_oid, m_exclusive,
+                                         &m_locker, ctx);
+  req->send();
+}
+
+template <typename I>
+void AcquireRequest<I>::handle_get_locker(int r) {
+  ldout(m_cct, 10) << "r=" << r << dendl;
+
+  if (r == -ENOENT) {
+    ldout(m_cct, 20) << "no lockers detected" << dendl;
+    m_locker = {};
+  } else if (r == -EBUSY) {
+    ldout(m_cct, 5) << "incompatible lock detected" << dendl;
+    finish(r);
+    return;
+  } else if (r < 0) {
+    lderr(m_cct) << "failed to retrieve lockers: " << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  send_lock();
+}
+
+template <typename I>
+void AcquireRequest<I>::send_lock() {
+  ldout(m_cct, 10) << "entity=client." << m_ioctx.get_instance_id() << ", "
+                   << "cookie=" << m_cookie << dendl;
+
+  librados::ObjectWriteOperation op;
+  rados::cls::lock::lock(&op, RBD_LOCK_NAME,
+                         m_exclusive ? LOCK_EXCLUSIVE : LOCK_SHARED, m_cookie,
+                         util::get_watcher_lock_tag(), "", utime_t(), 0);
+
+  using klass = AcquireRequest;
+  librados::AioCompletion *rados_completion =
+    create_rados_callback<klass, &klass::handle_lock>(this);
+  int r = m_ioctx.aio_operate(m_oid, rados_completion, &op);
+  assert(r == 0);
+  rados_completion->release();
+}
+
+template <typename I>
+void AcquireRequest<I>::handle_lock(int r) {
+  ldout(m_cct, 10) << "r=" << r << dendl;
+
+  if (r == 0) {
+    finish(0);
+    return;
+  } else if (r == -EBUSY && m_locker.cookie.empty()) {
+    ldout(m_cct, 5) << "already locked, refreshing locker" << dendl;
+    send_get_locker();
+    return;
+  } else if (r != -EBUSY) {
+    lderr(m_cct) << "failed to lock: " << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  send_break_lock();
+}
+
+template <typename I>
+void AcquireRequest<I>::send_break_lock() {
+  ldout(m_cct, 10) << dendl;
+
+  Context *ctx = create_context_callback<
+    AcquireRequest<I>, &AcquireRequest<I>::handle_break_lock>(this);
+  auto req = BreakRequest<I>::create(
+    m_ioctx, m_work_queue, m_oid, m_locker, m_exclusive,
+    m_blacklist_on_break_lock, m_blacklist_expire_seconds, false, ctx);
+  req->send();
+}
+
+template <typename I>
+void AcquireRequest<I>::handle_break_lock(int r) {
+  ldout(m_cct, 10) << "r=" << r << dendl;
+
+  if (r == -EAGAIN) {
+    ldout(m_cct, 5) << "lock owner is still alive" << dendl;
+    finish(r);
+    return;
+  } else if (r < 0) {
+    lderr(m_cct) << "failed to break lock : " << cpp_strerror(r) << dendl;
+    finish(r);
+    return;
+  }
+
+  m_locker = {};
+  send_lock();
+}
+
+template <typename I>
+void AcquireRequest<I>::finish(int r) {
+  m_on_finish->complete(r);
+  delete this;
+}
+
+} // namespace managed_lock
+} // namespace librbd
+
+template class librbd::managed_lock::AcquireRequest<librbd::ImageCtx>;