--- /dev/null
+// -*- 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>;
Code Review / stor4nfv.git / blobdiff