diff options
Diffstat (limited to 'src/librbd/mirror/DemoteRequest.cc')
| -rw-r--r-- | src/librbd/mirror/DemoteRequest.cc | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/src/librbd/mirror/DemoteRequest.cc b/src/librbd/mirror/DemoteRequest.cc new file mode 100644 index 000000000..350a76d83 --- /dev/null +++ b/src/librbd/mirror/DemoteRequest.cc @@ -0,0 +1,216 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +// vim: ts=8 sw=2 smarttab + +#include "librbd/mirror/DemoteRequest.h" +#include "common/dout.h" +#include "common/errno.h" +#include "cls/rbd/cls_rbd_client.h" +#include "librbd/ExclusiveLock.h" +#include "librbd/ImageCtx.h" +#include "librbd/ImageState.h" +#include "librbd/Journal.h" +#include "librbd/Utils.h" +#include "librbd/mirror/GetInfoRequest.h" +#include "librbd/mirror/snapshot/DemoteRequest.h" + +#define dout_subsys ceph_subsys_rbd +#undef dout_prefix +#define dout_prefix *_dout << "librbd::mirror::DemoteRequest: " << this \ + << " " << __func__ << ": " + +namespace librbd { +namespace mirror { + +using librbd::util::create_context_callback; + +template <typename I> +void DemoteRequest<I>::send() { + get_info(); +} + +template <typename I> +void DemoteRequest<I>::get_info() { + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << dendl; + + auto ctx = create_context_callback< + DemoteRequest<I>, &DemoteRequest<I>::handle_get_info>(this); + auto req = GetInfoRequest<I>::create(m_image_ctx, &m_mirror_image, + &m_promotion_state, + &m_primary_mirror_uuid, ctx); + req->send(); +} + +template <typename I> +void DemoteRequest<I>::handle_get_info(int r) { + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << "r=" << r << dendl; + + if (r < 0 && r != -ENOENT) { + lderr(cct) << "failed to retrieve mirroring state: " << cpp_strerror(r) + << dendl; + finish(r); + return; + } else if (m_mirror_image.state != cls::rbd::MIRROR_IMAGE_STATE_ENABLED) { + lderr(cct) << "mirroring is not currently enabled" << dendl; + finish(-EINVAL); + return; + } else if (m_promotion_state != PROMOTION_STATE_PRIMARY) { + lderr(cct) << "image is not primary" << dendl; + finish(-EINVAL); + return; + } + + acquire_lock(); +} + +template <typename I> +void DemoteRequest<I>::acquire_lock() { + CephContext *cct = m_image_ctx.cct; + + m_image_ctx.owner_lock.lock_shared(); + if (m_image_ctx.exclusive_lock == nullptr) { + m_image_ctx.owner_lock.unlock_shared(); + if (m_mirror_image.mode == cls::rbd::MIRROR_IMAGE_MODE_JOURNAL) { + lderr(cct) << "exclusive lock is not active" << dendl; + finish(-EINVAL); + } else { + demote(); + } + return; + } + + // avoid accepting new requests from peers while we demote + // the image + m_image_ctx.exclusive_lock->block_requests(0); + m_blocked_requests = true; + + if (m_image_ctx.exclusive_lock->is_lock_owner()) { + m_image_ctx.owner_lock.unlock_shared(); + demote(); + return; + } + + ldout(cct, 20) << dendl; + + auto ctx = create_context_callback< + DemoteRequest<I>, + &DemoteRequest<I>::handle_acquire_lock>(this, m_image_ctx.exclusive_lock); + m_image_ctx.exclusive_lock->acquire_lock(ctx); + m_image_ctx.owner_lock.unlock_shared(); +} + +template <typename I> +void DemoteRequest<I>::handle_acquire_lock(int r) { + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << "r=" << r << dendl; + + if (r < 0) { + lderr(cct) << "failed to lock image: " << cpp_strerror(r) << dendl; + finish(r); + return; + } + + m_image_ctx.owner_lock.lock_shared(); + if (m_image_ctx.exclusive_lock != nullptr && + !m_image_ctx.exclusive_lock->is_lock_owner()) { + r = m_image_ctx.exclusive_lock->get_unlocked_op_error(); + m_image_ctx.owner_lock.unlock_shared(); + lderr(cct) << "failed to acquire exclusive lock" << dendl; + finish(r); + return; + } + m_image_ctx.owner_lock.unlock_shared(); + + demote(); +} + +template <typename I> +void DemoteRequest<I>::demote() { + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << dendl; + + auto ctx = create_context_callback< + DemoteRequest<I>, &DemoteRequest<I>::handle_demote>(this); + if (m_mirror_image.mode == cls::rbd::MIRROR_IMAGE_MODE_JOURNAL) { + Journal<I>::demote(&m_image_ctx, ctx); + } else if (m_mirror_image.mode == cls::rbd::MIRROR_IMAGE_MODE_SNAPSHOT) { + auto req = mirror::snapshot::DemoteRequest<I>::create( + &m_image_ctx, m_mirror_image.global_image_id, ctx); + req->send(); + } else { + lderr(cct) << "unknown image mirror mode: " << m_mirror_image.mode << dendl; + m_ret_val = -EOPNOTSUPP; + release_lock(); + } +} + +template <typename I> +void DemoteRequest<I>::handle_demote(int r) { + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << "r=" << r << dendl; + + if (r < 0) { + m_ret_val = r; + lderr(cct) << "failed to demote image: " << cpp_strerror(r) << dendl; + } + + release_lock(); +} + +template <typename I> +void DemoteRequest<I>::release_lock() { + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << dendl; + + m_image_ctx.owner_lock.lock_shared(); + if (m_image_ctx.exclusive_lock == nullptr) { + m_image_ctx.owner_lock.unlock_shared(); + finish(0); + return; + } + + auto ctx = create_context_callback< + DemoteRequest<I>, + &DemoteRequest<I>::handle_release_lock>(this, m_image_ctx.exclusive_lock); + m_image_ctx.exclusive_lock->release_lock(ctx); + m_image_ctx.owner_lock.unlock_shared(); +} + +template <typename I> +void DemoteRequest<I>::handle_release_lock(int r) { + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << "r=" << r << dendl; + + if (r < 0) { + lderr(cct) << "failed to release exclusive lock: " << cpp_strerror(r) + << dendl; + } + + finish(r); +} + +template <typename I> +void DemoteRequest<I>::finish(int r) { + if (m_ret_val < 0) { + r = m_ret_val; + } + + { + std::shared_lock owner_locker{m_image_ctx.owner_lock}; + if (m_blocked_requests && m_image_ctx.exclusive_lock != nullptr) { + m_image_ctx.exclusive_lock->unblock_requests(); + } + } + + CephContext *cct = m_image_ctx.cct; + ldout(cct, 20) << "r=" << r << dendl; + + m_on_finish->complete(r); + delete this; +} + +} // namespace mirror +} // namespace librbd + +template class librbd::mirror::DemoteRequest<librbd::ImageCtx>; |