ceph/src/librbd/watcher/RewatchRequest.cc

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3
   4 #include "librbd/watcher/RewatchRequest.h"
   5 #include "common/RWLock.h"
   6 #include "common/errno.h"
   7 #include "librbd/Utils.h"
   8
   9 #define dout_subsys ceph_subsys_rbd
  10 #undef dout_prefix
  11 #define dout_prefix *_dout << "librbd::watcher::RewatchRequest: " \
  12                            << this << " " << __func__ << " "
  13
  14 namespace librbd {
  15
  16 using util::create_context_callback;
  17 using util::create_rados_callback;
  18
  19 namespace watcher {
  20
  21 using std::string;
  22
  23 RewatchRequest::RewatchRequest(librados::IoCtx& ioctx, const string& oid,
  24                                RWLock &watch_lock,
  25                                librados::WatchCtx2 *watch_ctx,
  26                                uint64_t *watch_handle, Context *on_finish)
  27   : m_ioctx(ioctx), m_oid(oid), m_watch_lock(watch_lock),
  28     m_watch_ctx(watch_ctx), m_watch_handle(watch_handle),
  29     m_on_finish(on_finish) {
  30 }
  31
  32 void RewatchRequest::send() {
  33   unwatch();
  34 }
  35
  36 void RewatchRequest::unwatch() {
  37   ceph_assert(m_watch_lock.is_wlocked());
  38   if (*m_watch_handle == 0) {
  39     rewatch();
  40     return;
  41   }
  42
  43   CephContext *cct = reinterpret_cast<CephContext *>(m_ioctx.cct());
  44   ldout(cct, 10) << dendl;
  45
  46   uint64_t watch_handle = 0;
  47   std::swap(*m_watch_handle, watch_handle);
  48
  49   librados::AioCompletion *aio_comp = create_rados_callback<
  50                         RewatchRequest, &RewatchRequest::handle_unwatch>(this);
  51   int r = m_ioctx.aio_unwatch(watch_handle, aio_comp);
  52   ceph_assert(r == 0);
  53   aio_comp->release();
  54 }
  55
  56 void RewatchRequest::handle_unwatch(int r) {
  57   CephContext *cct = reinterpret_cast<CephContext *>(m_ioctx.cct());
  58   ldout(cct, 10) << "r=" << r << dendl;
  59
  60   if (r == -EBLACKLISTED) {
  61     lderr(cct) << "client blacklisted" << dendl;
  62     finish(r);
  63     return;
  64   } else if (r < 0) {
  65     lderr(cct) << "failed to unwatch: " << cpp_strerror(r) << dendl;
  66   }
  67   rewatch();
  68 }
  69
  70 void RewatchRequest::rewatch() {
  71   CephContext *cct = reinterpret_cast<CephContext *>(m_ioctx.cct());
  72   ldout(cct, 10) << dendl;
  73
  74   librados::AioCompletion *aio_comp = create_rados_callback<
  75                         RewatchRequest, &RewatchRequest::handle_rewatch>(this);
  76   int r = m_ioctx.aio_watch(m_oid, aio_comp, &m_rewatch_handle, m_watch_ctx);
  77   ceph_assert(r == 0);
  78   aio_comp->release();
  79 }
  80
  81 void RewatchRequest::handle_rewatch(int r) {
  82   CephContext *cct = reinterpret_cast<CephContext *>(m_ioctx.cct());
  83   ldout(cct, 10) << "r=" << r << dendl;
  84   if (r < 0) {
  85     lderr(cct) << "failed to watch object: " << cpp_strerror(r)
  86                << dendl;
  87     m_rewatch_handle = 0;
  88   }
  89
  90   {
  91     RWLock::WLocker watch_locker(m_watch_lock);
  92     *m_watch_handle = m_rewatch_handle;
  93   }
  94
  95   finish(r);
  96 }
  97
  98 void RewatchRequest::finish(int r) {
  99   CephContext *cct = reinterpret_cast<CephContext *>(m_ioctx.cct());
 100   ldout(cct, 10) << "r=" << r << dendl;
 101
 102   m_on_finish->complete(r);
 103   delete this;
 104 }
 105
 106 } // namespace watcher
 107 } // namespace librbd
 108