-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-// vim: ts=8 sw=2 smarttab
-
-#include "librbd/image/SetSnapRequest.h"
-#include "common/dout.h"
-#include "common/errno.h"
-#include "librbd/ExclusiveLock.h"
-#include "librbd/ImageCtx.h"
-#include "librbd/ObjectMap.h"
-#include "librbd/Utils.h"
-#include "librbd/image/RefreshParentRequest.h"
-#include "librbd/io/ImageRequestWQ.h"
-
-#define dout_subsys ceph_subsys_rbd
-#undef dout_prefix
-#define dout_prefix *_dout << "librbd::image::SetSnapRequest: "
-
-namespace librbd {
-namespace image {
-
-using util::create_context_callback;
-
-template <typename I>
-SetSnapRequest<I>::SetSnapRequest(I &image_ctx, const cls::rbd::SnapshotNamespace& snap_namespace,
- const std::string &snap_name,
- Context *on_finish)
- : m_image_ctx(image_ctx), m_snap_namespace(snap_namespace),
- m_snap_name(snap_name), m_on_finish(on_finish),
- m_snap_id(CEPH_NOSNAP), m_exclusive_lock(nullptr), m_object_map(nullptr),
- m_refresh_parent(nullptr), m_writes_blocked(false) {
-}
-
-template <typename I>
-SetSnapRequest<I>::~SetSnapRequest() {
- assert(!m_writes_blocked);
- delete m_refresh_parent;
- delete m_object_map;
- delete m_exclusive_lock;
-}
-
-template <typename I>
-void SetSnapRequest<I>::send() {
- if (m_snap_name.empty()) {
- send_init_exclusive_lock();
- } else {
- send_block_writes();
- }
-}
-
-template <typename I>
-void SetSnapRequest<I>::send_init_exclusive_lock() {
- {
- RWLock::RLocker snap_locker(m_image_ctx.snap_lock);
- if (m_image_ctx.exclusive_lock != nullptr) {
- assert(m_image_ctx.snap_id == CEPH_NOSNAP);
- send_complete();
- return;
- }
- }
-
- if (m_image_ctx.read_only ||
- !m_image_ctx.test_features(RBD_FEATURE_EXCLUSIVE_LOCK)) {
- int r = 0;
- if (send_refresh_parent(&r) != nullptr) {
- send_complete();
- }
- return;
- }
-
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << dendl;
-
- m_exclusive_lock = ExclusiveLock<I>::create(m_image_ctx);
-
- using klass = SetSnapRequest<I>;
- Context *ctx = create_context_callback<
- klass, &klass::handle_init_exclusive_lock>(this);
-
- RWLock::RLocker owner_locker(m_image_ctx.owner_lock);
- m_exclusive_lock->init(m_image_ctx.features, ctx);
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::handle_init_exclusive_lock(int *result) {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << ": r=" << *result << dendl;
-
- if (*result < 0) {
- lderr(cct) << "failed to initialize exclusive lock: "
- << cpp_strerror(*result) << dendl;
- finalize();
- return m_on_finish;
- }
- return send_refresh_parent(result);
-}
-
-template <typename I>
-void SetSnapRequest<I>::send_block_writes() {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << dendl;
-
- m_writes_blocked = true;
-
- using klass = SetSnapRequest<I>;
- Context *ctx = create_context_callback<
- klass, &klass::handle_block_writes>(this);
-
- RWLock::RLocker owner_locker(m_image_ctx.owner_lock);
- m_image_ctx.io_work_queue->block_writes(ctx);
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::handle_block_writes(int *result) {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << ": r=" << *result << dendl;
-
- if (*result < 0) {
- lderr(cct) << "failed to block writes: " << cpp_strerror(*result)
- << dendl;
- finalize();
- return m_on_finish;
- }
-
- {
- RWLock::RLocker snap_locker(m_image_ctx.snap_lock);
- m_snap_id = m_image_ctx.get_snap_id(m_snap_namespace, m_snap_name);
- if (m_snap_id == CEPH_NOSNAP) {
- ldout(cct, 5) << "failed to locate snapshot '" << m_snap_name << "'"
- << dendl;
-
- *result = -ENOENT;
- finalize();
- return m_on_finish;
- }
- }
-
- return send_shut_down_exclusive_lock(result);
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::send_shut_down_exclusive_lock(int *result) {
- {
- RWLock::RLocker snap_locker(m_image_ctx.snap_lock);
- m_exclusive_lock = m_image_ctx.exclusive_lock;
- }
-
- if (m_exclusive_lock == nullptr) {
- return send_refresh_parent(result);
- }
-
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << dendl;
-
- using klass = SetSnapRequest<I>;
- Context *ctx = create_context_callback<
- klass, &klass::handle_shut_down_exclusive_lock>(this);
- m_exclusive_lock->shut_down(ctx);
- return nullptr;
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::handle_shut_down_exclusive_lock(int *result) {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << ": r=" << *result << dendl;
-
- if (*result < 0) {
- lderr(cct) << "failed to shut down exclusive lock: "
- << cpp_strerror(*result) << dendl;
- finalize();
- return m_on_finish;
- }
-
- return send_refresh_parent(result);
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::send_refresh_parent(int *result) {
- CephContext *cct = m_image_ctx.cct;
-
- ParentInfo parent_md;
- bool refresh_parent;
- {
- RWLock::RLocker snap_locker(m_image_ctx.snap_lock);
- RWLock::RLocker parent_locker(m_image_ctx.parent_lock);
-
- const ParentInfo *parent_info = m_image_ctx.get_parent_info(m_snap_id);
- if (parent_info == nullptr) {
- *result = -ENOENT;
- lderr(cct) << "failed to retrieve snapshot parent info" << dendl;
- finalize();
- return m_on_finish;
- }
-
- parent_md = *parent_info;
- refresh_parent = RefreshParentRequest<I>::is_refresh_required(m_image_ctx,
- parent_md);
- }
-
- if (!refresh_parent) {
- if (m_snap_id == CEPH_NOSNAP) {
- // object map is loaded when exclusive lock is acquired
- *result = apply();
- finalize();
- return m_on_finish;
- } else {
- // load snapshot object map
- return send_open_object_map(result);
- }
- }
-
- ldout(cct, 10) << __func__ << dendl;
-
- using klass = SetSnapRequest<I>;
- Context *ctx = create_context_callback<
- klass, &klass::handle_refresh_parent>(this);
- m_refresh_parent = RefreshParentRequest<I>::create(m_image_ctx, parent_md,
- ctx);
- m_refresh_parent->send();
- return nullptr;
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::handle_refresh_parent(int *result) {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << ": r=" << *result << dendl;
-
- if (*result < 0) {
- lderr(cct) << "failed to refresh snapshot parent: " << cpp_strerror(*result)
- << dendl;
- finalize();
- return m_on_finish;
- }
-
- if (m_snap_id == CEPH_NOSNAP) {
- // object map is loaded when exclusive lock is acquired
- *result = apply();
- if (*result < 0) {
- finalize();
- return m_on_finish;
- }
-
- return send_finalize_refresh_parent(result);
- } else {
- // load snapshot object map
- return send_open_object_map(result);
- }
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::send_open_object_map(int *result) {
- if (!m_image_ctx.test_features(RBD_FEATURE_OBJECT_MAP)) {
- *result = apply();
- if (*result < 0) {
- finalize();
- return m_on_finish;
- }
-
- return send_finalize_refresh_parent(result);
- }
-
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << dendl;
-
- using klass = SetSnapRequest<I>;
- Context *ctx = create_context_callback<
- klass, &klass::handle_open_object_map>(this);
- m_object_map = ObjectMap<I>::create(m_image_ctx, m_snap_id);
- m_object_map->open(ctx);
- return nullptr;
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::handle_open_object_map(int *result) {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << ": r=" << *result << dendl;
-
- if (*result < 0) {
- lderr(cct) << "failed to open object map: " << cpp_strerror(*result)
- << dendl;
- delete m_object_map;
- m_object_map = nullptr;
- }
-
- *result = apply();
- if (*result < 0) {
- finalize();
- return m_on_finish;
- }
-
- return send_finalize_refresh_parent(result);
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::send_finalize_refresh_parent(int *result) {
- if (m_refresh_parent == nullptr) {
- finalize();
- return m_on_finish;
- }
-
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << this << " " << __func__ << dendl;
-
- using klass = SetSnapRequest<I>;
- Context *ctx = create_context_callback<
- klass, &klass::handle_finalize_refresh_parent>(this);
- m_refresh_parent->finalize(ctx);
- return nullptr;
-}
-
-template <typename I>
-Context *SetSnapRequest<I>::handle_finalize_refresh_parent(int *result) {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << this << " " << __func__ << ": r=" << *result << dendl;
-
- if (*result < 0) {
- lderr(cct) << "failed to close parent image: " << cpp_strerror(*result)
- << dendl;
- }
- finalize();
- return m_on_finish;
-}
-
-template <typename I>
-int SetSnapRequest<I>::apply() {
- CephContext *cct = m_image_ctx.cct;
- ldout(cct, 10) << __func__ << dendl;
-
- RWLock::WLocker owner_locker(m_image_ctx.owner_lock);
- RWLock::WLocker snap_locker(m_image_ctx.snap_lock);
- RWLock::WLocker parent_locker(m_image_ctx.parent_lock);
- if (m_snap_id != CEPH_NOSNAP) {
- assert(m_image_ctx.exclusive_lock == nullptr);
- int r = m_image_ctx.snap_set(m_snap_namespace, m_snap_name);
- if (r < 0) {
- return r;
- }
- } else {
- std::swap(m_image_ctx.exclusive_lock, m_exclusive_lock);
- m_image_ctx.snap_unset();
- }
-
- if (m_refresh_parent != nullptr) {
- m_refresh_parent->apply();
- }
-
- std::swap(m_object_map, m_image_ctx.object_map);
- return 0;
-}
-
-template <typename I>
-void SetSnapRequest<I>::finalize() {
- if (m_writes_blocked) {
- m_image_ctx.io_work_queue->unblock_writes();
- m_writes_blocked = false;
- }
-}
-
-template <typename I>
-void SetSnapRequest<I>::send_complete() {
- finalize();
- m_on_finish->complete(0);
- delete this;
-}
-
-} // namespace image
-} // namespace librbd
-
-template class librbd::image::SetSnapRequest<librbd::ImageCtx>;