+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "SnapshotCopyRequest.h"
+#include "SnapshotCreateRequest.h"
+#include "common/errno.h"
+#include "common/WorkQueue.h"
+#include "journal/Journaler.h"
+#include "librbd/ExclusiveLock.h"
+#include "librbd/Operations.h"
+#include "librbd/Utils.h"
+#include "librbd/journal/Types.h"
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_rbd_mirror
+#undef dout_prefix
+#define dout_prefix *_dout << "rbd::mirror::image_sync::SnapshotCopyRequest: " \
+ << this << " " << __func__
+
+namespace rbd {
+namespace mirror {
+namespace image_sync {
+
+namespace {
+
+template <typename I>
+const std::string &get_snapshot_name(I *image_ctx, librados::snap_t snap_id) {
+ auto snap_it = std::find_if(image_ctx->snap_ids.begin(),
+ image_ctx->snap_ids.end(),
+ [snap_id](
+ const std::pair<
+ std::pair<cls::rbd::SnapshotNamespace,
+ std::string>,
+ librados::snap_t> &pair) {
+ return pair.second == snap_id;
+ });
+ assert(snap_it != image_ctx->snap_ids.end());
+ return snap_it->first.second;
+}
+
+} // anonymous namespace
+
+using librbd::util::create_context_callback;
+using librbd::util::unique_lock_name;
+
+template <typename I>
+SnapshotCopyRequest<I>::SnapshotCopyRequest(I *local_image_ctx,
+ I *remote_image_ctx,
+ SnapMap *snap_map,
+ Journaler *journaler,
+ librbd::journal::MirrorPeerClientMeta *meta,
+ ContextWQ *work_queue,
+ Context *on_finish)
+ : BaseRequest("rbd::mirror::image_sync::SnapshotCopyRequest",
+ local_image_ctx->cct, on_finish),
+ m_local_image_ctx(local_image_ctx), m_remote_image_ctx(remote_image_ctx),
+ m_snap_map(snap_map), m_journaler(journaler), m_client_meta(meta),
+ m_work_queue(work_queue), m_snap_seqs(meta->snap_seqs),
+ m_lock(unique_lock_name("SnapshotCopyRequest::m_lock", this)) {
+ m_snap_map->clear();
+
+ // snap ids ordered from oldest to newest
+ m_remote_snap_ids.insert(remote_image_ctx->snaps.begin(),
+ remote_image_ctx->snaps.end());
+ m_local_snap_ids.insert(local_image_ctx->snaps.begin(),
+ local_image_ctx->snaps.end());
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::send() {
+ librbd::ParentSpec remote_parent_spec;
+ int r = validate_parent(m_remote_image_ctx, &remote_parent_spec);
+ if (r < 0) {
+ derr << ": remote image parent spec mismatch" << dendl;
+ error(r);
+ return;
+ }
+
+ r = validate_parent(m_local_image_ctx, &m_local_parent_spec);
+ if (r < 0) {
+ derr << ": local image parent spec mismatch" << dendl;
+ error(r);
+ return;
+ }
+
+ send_snap_unprotect();
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::cancel() {
+ Mutex::Locker locker(m_lock);
+
+ dout(20) << dendl;
+ m_canceled = true;
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::send_snap_unprotect() {
+
+ SnapIdSet::iterator snap_id_it = m_local_snap_ids.begin();
+ if (m_prev_snap_id != CEPH_NOSNAP) {
+ snap_id_it = m_local_snap_ids.upper_bound(m_prev_snap_id);
+ }
+
+ for (; snap_id_it != m_local_snap_ids.end(); ++snap_id_it) {
+ librados::snap_t local_snap_id = *snap_id_it;
+
+ m_local_image_ctx->snap_lock.get_read();
+
+ bool local_unprotected;
+ int r = m_local_image_ctx->is_snap_unprotected(local_snap_id,
+ &local_unprotected);
+ if (r < 0) {
+ derr << ": failed to retrieve local snap unprotect status: "
+ << cpp_strerror(r) << dendl;
+ m_local_image_ctx->snap_lock.put_read();
+ finish(r);
+ return;
+ }
+ m_local_image_ctx->snap_lock.put_read();
+
+ if (local_unprotected) {
+ // snap is already unprotected -- check next snap
+ continue;
+ }
+
+ // if local snapshot is protected and (1) it isn't in our mapping
+ // table, or (2) the remote snapshot isn't protected, unprotect it
+ auto snap_seq_it = std::find_if(
+ m_snap_seqs.begin(), m_snap_seqs.end(),
+ [local_snap_id](const SnapSeqs::value_type& pair) {
+ return pair.second == local_snap_id;
+ });
+
+ if (snap_seq_it != m_snap_seqs.end()) {
+ m_remote_image_ctx->snap_lock.get_read();
+ bool remote_unprotected;
+ r = m_remote_image_ctx->is_snap_unprotected(snap_seq_it->first,
+ &remote_unprotected);
+ if (r < 0) {
+ derr << ": failed to retrieve remote snap unprotect status: "
+ << cpp_strerror(r) << dendl;
+ m_remote_image_ctx->snap_lock.put_read();
+ finish(r);
+ return;
+ }
+ m_remote_image_ctx->snap_lock.put_read();
+
+ if (remote_unprotected) {
+ // remote is unprotected -- unprotect local snap
+ break;
+ }
+ } else {
+ // remote snapshot doesn't exist -- unprotect local snap
+ break;
+ }
+ }
+
+ if (snap_id_it == m_local_snap_ids.end()) {
+ // no local snapshots to unprotect
+ m_prev_snap_id = CEPH_NOSNAP;
+ send_snap_remove();
+ return;
+ }
+
+ m_prev_snap_id = *snap_id_it;
+ m_snap_name = get_snapshot_name(m_local_image_ctx, m_prev_snap_id);
+
+ dout(20) << ": "
+ << "snap_name=" << m_snap_name << ", "
+ << "snap_id=" << m_prev_snap_id << dendl;
+
+ auto finish_op_ctx = start_local_op();
+ if (finish_op_ctx == nullptr) {
+ derr << ": lost exclusive lock" << dendl;
+ finish(-EROFS);
+ return;
+ }
+
+ auto ctx = new FunctionContext([this, finish_op_ctx](int r) {
+ handle_snap_unprotect(r);
+ finish_op_ctx->complete(0);
+ });
+ RWLock::RLocker owner_locker(m_local_image_ctx->owner_lock);
+ m_local_image_ctx->operations->execute_snap_unprotect(
+ cls::rbd::UserSnapshotNamespace(), m_snap_name.c_str(), ctx);
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::handle_snap_unprotect(int r) {
+ dout(20) << ": r=" << r << dendl;
+
+ if (r < 0) {
+ derr << ": failed to unprotect snapshot '" << m_snap_name << "': "
+ << cpp_strerror(r) << dendl;
+ finish(r);
+ return;
+ }
+ if (handle_cancellation())
+ {
+ return;
+ }
+
+ send_snap_unprotect();
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::send_snap_remove() {
+ SnapIdSet::iterator snap_id_it = m_local_snap_ids.begin();
+ if (m_prev_snap_id != CEPH_NOSNAP) {
+ snap_id_it = m_local_snap_ids.upper_bound(m_prev_snap_id);
+ }
+
+ for (; snap_id_it != m_local_snap_ids.end(); ++snap_id_it) {
+ librados::snap_t local_snap_id = *snap_id_it;
+
+ cls::rbd::SnapshotNamespace snap_namespace;
+ m_local_image_ctx->snap_lock.get_read();
+ int r = m_local_image_ctx->get_snap_namespace(local_snap_id,
+ &snap_namespace);
+ m_local_image_ctx->snap_lock.put_read();
+ if (r < 0) {
+ derr << ": failed to retrieve local snap namespace: " << m_snap_name
+ << dendl;
+ finish(r);
+ return;
+ }
+
+ if (boost::get<cls::rbd::UserSnapshotNamespace>(&snap_namespace) ==
+ nullptr) {
+ continue;
+ }
+
+ // if the local snapshot isn't in our mapping table, remove it
+ auto snap_seq_it = std::find_if(
+ m_snap_seqs.begin(), m_snap_seqs.end(),
+ [local_snap_id](const SnapSeqs::value_type& pair) {
+ return pair.second == local_snap_id;
+ });
+
+ if (snap_seq_it == m_snap_seqs.end()) {
+ break;
+ }
+ }
+
+ if (snap_id_it == m_local_snap_ids.end()) {
+ // no local snapshots to delete
+ m_prev_snap_id = CEPH_NOSNAP;
+ send_snap_create();
+ return;
+ }
+
+ m_prev_snap_id = *snap_id_it;
+ m_snap_name = get_snapshot_name(m_local_image_ctx, m_prev_snap_id);
+
+ dout(20) << ": "
+ << "snap_name=" << m_snap_name << ", "
+ << "snap_id=" << m_prev_snap_id << dendl;
+
+ auto finish_op_ctx = start_local_op();
+ if (finish_op_ctx == nullptr) {
+ derr << ": lost exclusive lock" << dendl;
+ finish(-EROFS);
+ return;
+ }
+
+ auto ctx = new FunctionContext([this, finish_op_ctx](int r) {
+ handle_snap_remove(r);
+ finish_op_ctx->complete(0);
+ });
+ RWLock::RLocker owner_locker(m_local_image_ctx->owner_lock);
+ m_local_image_ctx->operations->execute_snap_remove(
+ cls::rbd::UserSnapshotNamespace(), m_snap_name.c_str(), ctx);
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::handle_snap_remove(int r) {
+ dout(20) << ": r=" << r << dendl;
+
+ if (r < 0) {
+ derr << ": failed to remove snapshot '" << m_snap_name << "': "
+ << cpp_strerror(r) << dendl;
+ finish(r);
+ return;
+ }
+ if (handle_cancellation())
+ {
+ return;
+ }
+
+ send_snap_remove();
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::send_snap_create() {
+ SnapIdSet::iterator snap_id_it = m_remote_snap_ids.begin();
+ if (m_prev_snap_id != CEPH_NOSNAP) {
+ snap_id_it = m_remote_snap_ids.upper_bound(m_prev_snap_id);
+ }
+
+ for (; snap_id_it != m_remote_snap_ids.end(); ++snap_id_it) {
+ librados::snap_t remote_snap_id = *snap_id_it;
+
+ cls::rbd::SnapshotNamespace snap_namespace;
+ m_remote_image_ctx->snap_lock.get_read();
+ int r = m_remote_image_ctx->get_snap_namespace(remote_snap_id, &snap_namespace);
+ m_remote_image_ctx->snap_lock.put_read();
+ if (r < 0) {
+ derr << ": failed to retrieve remote snap namespace: " << m_snap_name
+ << dendl;
+ finish(r);
+ return;
+ }
+
+ // if the remote snapshot isn't in our mapping table, create it
+ if (m_snap_seqs.find(remote_snap_id) == m_snap_seqs.end() &&
+ boost::get<cls::rbd::UserSnapshotNamespace>(&snap_namespace) != nullptr) {
+ break;
+ }
+ }
+
+ if (snap_id_it == m_remote_snap_ids.end()) {
+ // no remote snapshots to create
+ m_prev_snap_id = CEPH_NOSNAP;
+ send_snap_protect();
+ return;
+ }
+
+ m_prev_snap_id = *snap_id_it;
+ m_snap_name = get_snapshot_name(m_remote_image_ctx, m_prev_snap_id);
+
+ m_remote_image_ctx->snap_lock.get_read();
+ auto snap_info_it = m_remote_image_ctx->snap_info.find(m_prev_snap_id);
+ if (snap_info_it == m_remote_image_ctx->snap_info.end()) {
+ m_remote_image_ctx->snap_lock.put_read();
+ derr << ": failed to retrieve remote snap info: " << m_snap_name
+ << dendl;
+ finish(-ENOENT);
+ return;
+ }
+
+ uint64_t size = snap_info_it->second.size;
+ m_snap_namespace = snap_info_it->second.snap_namespace;
+ librbd::ParentSpec parent_spec;
+ uint64_t parent_overlap = 0;
+ if (snap_info_it->second.parent.spec.pool_id != -1) {
+ parent_spec = m_local_parent_spec;
+ parent_overlap = snap_info_it->second.parent.overlap;
+ }
+ m_remote_image_ctx->snap_lock.put_read();
+
+
+ dout(20) << ": "
+ << "snap_name=" << m_snap_name << ", "
+ << "snap_id=" << m_prev_snap_id << ", "
+ << "size=" << size << ", "
+ << "parent_info=["
+ << "pool_id=" << parent_spec.pool_id << ", "
+ << "image_id=" << parent_spec.image_id << ", "
+ << "snap_id=" << parent_spec.snap_id << ", "
+ << "overlap=" << parent_overlap << "]" << dendl;
+
+ Context *finish_op_ctx = start_local_op();
+ if (finish_op_ctx == nullptr) {
+ derr << ": lost exclusive lock" << dendl;
+ finish(-EROFS);
+ return;
+ }
+
+ auto ctx = new FunctionContext([this, finish_op_ctx](int r) {
+ handle_snap_create(r);
+ finish_op_ctx->complete(0);
+ });
+ SnapshotCreateRequest<I> *req = SnapshotCreateRequest<I>::create(
+ m_local_image_ctx, m_snap_name, m_snap_namespace, size, parent_spec,
+ parent_overlap, ctx);
+ req->send();
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::handle_snap_create(int r) {
+ dout(20) << ": r=" << r << dendl;
+
+ if (r < 0) {
+ derr << ": failed to create snapshot '" << m_snap_name << "': "
+ << cpp_strerror(r) << dendl;
+ finish(r);
+ return;
+ }
+ if (handle_cancellation())
+ {
+ return;
+ }
+
+ assert(m_prev_snap_id != CEPH_NOSNAP);
+
+ auto snap_it = m_local_image_ctx->snap_ids.find({cls::rbd::UserSnapshotNamespace(),
+ m_snap_name});
+ assert(snap_it != m_local_image_ctx->snap_ids.end());
+ librados::snap_t local_snap_id = snap_it->second;
+
+ dout(20) << ": mapping remote snap id " << m_prev_snap_id << " to "
+ << local_snap_id << dendl;
+ m_snap_seqs[m_prev_snap_id] = local_snap_id;
+
+ send_snap_create();
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::send_snap_protect() {
+ SnapIdSet::iterator snap_id_it = m_remote_snap_ids.begin();
+ if (m_prev_snap_id != CEPH_NOSNAP) {
+ snap_id_it = m_remote_snap_ids.upper_bound(m_prev_snap_id);
+ }
+
+ for (; snap_id_it != m_remote_snap_ids.end(); ++snap_id_it) {
+ librados::snap_t remote_snap_id = *snap_id_it;
+
+ m_remote_image_ctx->snap_lock.get_read();
+
+ bool remote_protected;
+ int r = m_remote_image_ctx->is_snap_protected(remote_snap_id,
+ &remote_protected);
+ if (r < 0) {
+ derr << ": failed to retrieve remote snap protect status: "
+ << cpp_strerror(r) << dendl;
+ m_remote_image_ctx->snap_lock.put_read();
+ finish(r);
+ return;
+ }
+ m_remote_image_ctx->snap_lock.put_read();
+
+ if (!remote_protected) {
+ // snap is not protected -- check next snap
+ continue;
+ }
+
+ // if local snapshot is not protected, protect it
+ auto snap_seq_it = m_snap_seqs.find(remote_snap_id);
+ assert(snap_seq_it != m_snap_seqs.end());
+
+ m_local_image_ctx->snap_lock.get_read();
+ bool local_protected;
+ r = m_local_image_ctx->is_snap_protected(snap_seq_it->second,
+ &local_protected);
+ if (r < 0) {
+ derr << ": failed to retrieve local snap protect status: "
+ << cpp_strerror(r) << dendl;
+ m_local_image_ctx->snap_lock.put_read();
+ finish(r);
+ return;
+ }
+ m_local_image_ctx->snap_lock.put_read();
+
+ if (!local_protected) {
+ break;
+ }
+ }
+
+ if (snap_id_it == m_remote_snap_ids.end()) {
+ // no local snapshots to protect
+ m_prev_snap_id = CEPH_NOSNAP;
+ send_update_client();
+ return;
+ }
+
+ m_prev_snap_id = *snap_id_it;
+ m_snap_name = get_snapshot_name(m_remote_image_ctx, m_prev_snap_id);
+
+ dout(20) << ": "
+ << "snap_name=" << m_snap_name << ", "
+ << "snap_id=" << m_prev_snap_id << dendl;
+
+ auto finish_op_ctx = start_local_op();
+ if (finish_op_ctx == nullptr) {
+ derr << ": lost exclusive lock" << dendl;
+ finish(-EROFS);
+ return;
+ }
+
+ auto ctx = new FunctionContext([this, finish_op_ctx](int r) {
+ handle_snap_protect(r);
+ finish_op_ctx->complete(0);
+ });
+ RWLock::RLocker owner_locker(m_local_image_ctx->owner_lock);
+ m_local_image_ctx->operations->execute_snap_protect(
+ cls::rbd::UserSnapshotNamespace(), m_snap_name.c_str(), ctx);
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::handle_snap_protect(int r) {
+ dout(20) << ": r=" << r << dendl;
+
+ if (r < 0) {
+ derr << ": failed to protect snapshot '" << m_snap_name << "': "
+ << cpp_strerror(r) << dendl;
+ finish(r);
+ return;
+ }
+ if (handle_cancellation())
+ {
+ return;
+ }
+
+ send_snap_protect();
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::send_update_client() {
+ dout(20) << dendl;
+
+ compute_snap_map();
+
+ librbd::journal::MirrorPeerClientMeta client_meta(*m_client_meta);
+ client_meta.snap_seqs = m_snap_seqs;
+
+ librbd::journal::ClientData client_data(client_meta);
+ bufferlist data_bl;
+ ::encode(client_data, data_bl);
+
+ Context *ctx = create_context_callback<
+ SnapshotCopyRequest<I>, &SnapshotCopyRequest<I>::handle_update_client>(
+ this);
+ m_journaler->update_client(data_bl, ctx);
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::handle_update_client(int r) {
+ dout(20) << ": r=" << r << dendl;
+
+ if (r < 0) {
+ derr << ": failed to update client data: " << cpp_strerror(r)
+ << dendl;
+ finish(r);
+ return;
+ }
+ if (handle_cancellation())
+ {
+ return;
+ }
+
+ m_client_meta->snap_seqs = m_snap_seqs;
+
+ finish(0);
+}
+
+template <typename I>
+bool SnapshotCopyRequest<I>::handle_cancellation() {
+ {
+ Mutex::Locker locker(m_lock);
+ if (!m_canceled) {
+ return false;
+ }
+ }
+ dout(10) << ": snapshot copy canceled" << dendl;
+ finish(-ECANCELED);
+ return true;
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::error(int r) {
+ dout(20) << ": r=" << r << dendl;
+
+ m_work_queue->queue(new FunctionContext([this, r](int r1) { finish(r); }));
+}
+
+template <typename I>
+void SnapshotCopyRequest<I>::compute_snap_map() {
+ SnapIds local_snap_ids;
+ for (auto &pair : m_snap_seqs) {
+ local_snap_ids.reserve(1 + local_snap_ids.size());
+ local_snap_ids.insert(local_snap_ids.begin(), pair.second);
+ m_snap_map->insert(std::make_pair(pair.first, local_snap_ids));
+ }
+}
+
+template <typename I>
+int SnapshotCopyRequest<I>::validate_parent(I *image_ctx,
+ librbd::ParentSpec *spec) {
+ RWLock::RLocker owner_locker(image_ctx->owner_lock);
+ RWLock::RLocker snap_locker(image_ctx->snap_lock);
+
+ // ensure remote image's parent specs are still consistent
+ *spec = image_ctx->parent_md.spec;
+ for (auto &snap_info_pair : image_ctx->snap_info) {
+ auto &parent_spec = snap_info_pair.second.parent.spec;
+ if (parent_spec.pool_id == -1) {
+ continue;
+ } else if (spec->pool_id == -1) {
+ *spec = parent_spec;
+ continue;
+ }
+
+ if (*spec != parent_spec) {
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
+template <typename I>
+Context *SnapshotCopyRequest<I>::start_local_op() {
+ RWLock::RLocker owner_locker(m_local_image_ctx->owner_lock);
+ if (m_local_image_ctx->exclusive_lock == nullptr) {
+ return nullptr;
+ }
+ return m_local_image_ctx->exclusive_lock->start_op();
+}
+
+} // namespace image_sync
+} // namespace mirror
+} // namespace rbd
+
+template class rbd::mirror::image_sync::SnapshotCopyRequest<librbd::ImageCtx>;