--- /dev/null
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/io/CopyupRequest.h"
+#include "common/ceph_context.h"
+#include "common/dout.h"
+#include "common/errno.h"
+#include "common/Mutex.h"
+
+#include "librbd/AsyncObjectThrottle.h"
+#include "librbd/ExclusiveLock.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/ObjectMap.h"
+#include "librbd/Utils.h"
+#include "librbd/io/AioCompletion.h"
+#include "librbd/io/ImageRequest.h"
+#include "librbd/io/ObjectRequest.h"
+#include "librbd/io/ReadResult.h"
+
+#include <boost/bind.hpp>
+#include <boost/lambda/bind.hpp>
+#include <boost/lambda/construct.hpp>
+
+#define dout_subsys ceph_subsys_rbd
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::io::CopyupRequest: " << this \
+ << " " << __func__ << ": "
+
+namespace librbd {
+namespace io {
+
+namespace {
+
+class UpdateObjectMap : public C_AsyncObjectThrottle<> {
+public:
+ UpdateObjectMap(AsyncObjectThrottle<> &throttle, ImageCtx *image_ctx,
+ uint64_t object_no, const std::vector<uint64_t> *snap_ids,
+ const ZTracer::Trace &trace, size_t snap_id_idx)
+ : C_AsyncObjectThrottle(throttle, *image_ctx), m_object_no(object_no),
+ m_snap_ids(*snap_ids), m_trace(trace), m_snap_id_idx(snap_id_idx)
+ {
+ }
+
+ int send() override {
+ uint64_t snap_id = m_snap_ids[m_snap_id_idx];
+ if (snap_id == CEPH_NOSNAP) {
+ RWLock::RLocker snap_locker(m_image_ctx.snap_lock);
+ RWLock::WLocker object_map_locker(m_image_ctx.object_map_lock);
+ assert(m_image_ctx.exclusive_lock->is_lock_owner());
+ assert(m_image_ctx.object_map != nullptr);
+ bool sent = m_image_ctx.object_map->aio_update<Context>(
+ CEPH_NOSNAP, m_object_no, OBJECT_EXISTS, {}, m_trace, this);
+ return (sent ? 0 : 1);
+ }
+
+ uint8_t state = OBJECT_EXISTS;
+ if (m_image_ctx.test_features(RBD_FEATURE_FAST_DIFF) &&
+ m_snap_id_idx + 1 < m_snap_ids.size()) {
+ state = OBJECT_EXISTS_CLEAN;
+ }
+
+ RWLock::RLocker snap_locker(m_image_ctx.snap_lock);
+ RWLock::RLocker object_map_locker(m_image_ctx.object_map_lock);
+ if (m_image_ctx.object_map == nullptr) {
+ return 1;
+ }
+
+ bool sent = m_image_ctx.object_map->aio_update<Context>(
+ snap_id, m_object_no, state, {}, m_trace, this);
+ assert(sent);
+ return 0;
+ }
+
+private:
+ uint64_t m_object_no;
+ const std::vector<uint64_t> &m_snap_ids;
+ const ZTracer::Trace &m_trace;
+ size_t m_snap_id_idx;
+};
+
+} // anonymous namespace
+
+
+CopyupRequest::CopyupRequest(ImageCtx *ictx, const std::string &oid,
+ uint64_t objectno, Extents &&image_extents,
+ const ZTracer::Trace &parent_trace)
+ : m_ictx(ictx), m_oid(oid), m_object_no(objectno),
+ m_image_extents(image_extents),
+ m_trace(util::create_trace(*m_ictx, "copy-up", parent_trace)),
+ m_state(STATE_READ_FROM_PARENT)
+{
+ m_async_op.start_op(*m_ictx);
+}
+
+CopyupRequest::~CopyupRequest() {
+ assert(m_pending_requests.empty());
+ m_async_op.finish_op();
+}
+
+void CopyupRequest::append_request(ObjectRequest<> *req) {
+ ldout(m_ictx->cct, 20) << req << dendl;
+ m_pending_requests.push_back(req);
+}
+
+void CopyupRequest::complete_requests(int r) {
+ while (!m_pending_requests.empty()) {
+ vector<ObjectRequest<> *>::iterator it = m_pending_requests.begin();
+ ObjectRequest<> *req = *it;
+ ldout(m_ictx->cct, 20) << "completing request " << req << dendl;
+ req->complete(r);
+ m_pending_requests.erase(it);
+ }
+}
+
+bool CopyupRequest::send_copyup() {
+ bool add_copyup_op = !m_copyup_data.is_zero();
+ bool copy_on_read = m_pending_requests.empty();
+ if (!add_copyup_op && copy_on_read) {
+ // copyup empty object to prevent future CoR attempts
+ m_copyup_data.clear();
+ add_copyup_op = true;
+ }
+
+ ldout(m_ictx->cct, 20) << "oid " << m_oid << dendl;
+ m_state = STATE_COPYUP;
+
+ m_ictx->snap_lock.get_read();
+ ::SnapContext snapc = m_ictx->snapc;
+ m_ictx->snap_lock.put_read();
+
+ std::vector<librados::snap_t> snaps;
+
+ if (!copy_on_read) {
+ m_pending_copyups++;
+ }
+
+ int r;
+ if (copy_on_read || (!snapc.snaps.empty() && add_copyup_op)) {
+ assert(add_copyup_op);
+ add_copyup_op = false;
+
+ librados::ObjectWriteOperation copyup_op;
+ copyup_op.exec("rbd", "copyup", m_copyup_data);
+
+ // send only the copyup request with a blank snapshot context so that
+ // all snapshots are detected from the parent for this object. If
+ // this is a CoW request, a second request will be created for the
+ // actual modification.
+ m_pending_copyups++;
+
+ ldout(m_ictx->cct, 20) << "copyup with empty snapshot context" << dendl;
+ librados::AioCompletion *comp = util::create_rados_callback(this);
+
+ librados::Rados rados(m_ictx->data_ctx);
+ r = rados.ioctx_create2(m_ictx->data_ctx.get_id(), m_data_ctx);
+ assert(r == 0);
+
+ r = m_data_ctx.aio_operate(
+ m_oid, comp, ©up_op, 0, snaps,
+ (m_trace.valid() ? m_trace.get_info() : nullptr));
+ assert(r == 0);
+ comp->release();
+ }
+
+ if (!copy_on_read) {
+ librados::ObjectWriteOperation write_op;
+ if (add_copyup_op) {
+ // CoW did not need to handle existing snapshots
+ write_op.exec("rbd", "copyup", m_copyup_data);
+ }
+
+ // merge all pending write ops into this single RADOS op
+ for (size_t i=0; i<m_pending_requests.size(); ++i) {
+ ObjectRequest<> *req = m_pending_requests[i];
+ ldout(m_ictx->cct, 20) << "add_copyup_ops " << req << dendl;
+ bool set_hints = (i == 0);
+ req->add_copyup_ops(&write_op, set_hints);
+ }
+ assert(write_op.size() != 0);
+
+ snaps.insert(snaps.end(), snapc.snaps.begin(), snapc.snaps.end());
+ librados::AioCompletion *comp = util::create_rados_callback(this);
+ r = m_ictx->data_ctx.aio_operate(
+ m_oid, comp, &write_op, snapc.seq, snaps,
+ (m_trace.valid() ? m_trace.get_info() : nullptr));
+ assert(r == 0);
+ comp->release();
+ }
+ return false;
+}
+
+bool CopyupRequest::is_copyup_required() {
+ bool noop = true;
+ for (const ObjectRequest<> *req : m_pending_requests) {
+ if (!req->is_op_payload_empty()) {
+ noop = false;
+ break;
+ }
+ }
+
+ return (m_copyup_data.is_zero() && noop);
+}
+
+void CopyupRequest::send()
+{
+ m_state = STATE_READ_FROM_PARENT;
+ AioCompletion *comp = AioCompletion::create_and_start(
+ this, m_ictx, AIO_TYPE_READ);
+
+ ldout(m_ictx->cct, 20) << "completion " << comp
+ << ", oid " << m_oid
+ << ", extents " << m_image_extents
+ << dendl;
+ ImageRequest<>::aio_read(m_ictx->parent, comp, std::move(m_image_extents),
+ ReadResult{&m_copyup_data}, 0, m_trace);
+}
+
+void CopyupRequest::complete(int r)
+{
+ if (should_complete(r)) {
+ complete_requests(r);
+ delete this;
+ }
+}
+
+bool CopyupRequest::should_complete(int r)
+{
+ CephContext *cct = m_ictx->cct;
+ ldout(cct, 20) << "oid " << m_oid
+ << ", r " << r << dendl;
+
+ uint64_t pending_copyups;
+ switch (m_state) {
+ case STATE_READ_FROM_PARENT:
+ ldout(cct, 20) << "READ_FROM_PARENT" << dendl;
+ remove_from_list();
+ if (r >= 0 || r == -ENOENT) {
+ if (is_copyup_required()) {
+ ldout(cct, 20) << "nop, skipping" << dendl;
+ return true;
+ }
+
+ return send_object_map_head();
+ }
+ break;
+
+ case STATE_OBJECT_MAP_HEAD:
+ ldout(cct, 20) << "OBJECT_MAP_HEAD" << dendl;
+ assert(r == 0);
+ return send_object_map();
+
+ case STATE_OBJECT_MAP:
+ ldout(cct, 20) << "OBJECT_MAP" << dendl;
+ assert(r == 0);
+ return send_copyup();
+
+ case STATE_COPYUP:
+ // invoked via a finisher in librados, so thread safe
+ pending_copyups = --m_pending_copyups;
+ ldout(cct, 20) << "COPYUP (" << pending_copyups << " pending)"
+ << dendl;
+ if (r == -ENOENT) {
+ // hide the -ENOENT error if this is the last op
+ if (pending_copyups == 0) {
+ complete_requests(0);
+ }
+ } else if (r < 0) {
+ complete_requests(r);
+ }
+ return (pending_copyups == 0);
+
+ default:
+ lderr(cct) << "invalid state: " << m_state << dendl;
+ assert(false);
+ break;
+ }
+ return (r < 0);
+}
+
+void CopyupRequest::remove_from_list()
+{
+ Mutex::Locker l(m_ictx->copyup_list_lock);
+
+ map<uint64_t, CopyupRequest*>::iterator it =
+ m_ictx->copyup_list.find(m_object_no);
+ assert(it != m_ictx->copyup_list.end());
+ m_ictx->copyup_list.erase(it);
+}
+
+bool CopyupRequest::send_object_map_head() {
+ CephContext *cct = m_ictx->cct;
+ ldout(cct, 20) << dendl;
+
+ m_state = STATE_OBJECT_MAP_HEAD;
+
+ {
+ RWLock::RLocker owner_locker(m_ictx->owner_lock);
+ RWLock::RLocker snap_locker(m_ictx->snap_lock);
+ if (m_ictx->object_map != nullptr) {
+ bool copy_on_read = m_pending_requests.empty();
+ assert(m_ictx->exclusive_lock->is_lock_owner());
+
+ RWLock::WLocker object_map_locker(m_ictx->object_map_lock);
+ if (!m_ictx->snaps.empty()) {
+ m_snap_ids.insert(m_snap_ids.end(), m_ictx->snaps.begin(),
+ m_ictx->snaps.end());
+ }
+ if (copy_on_read &&
+ (*m_ictx->object_map)[m_object_no] != OBJECT_EXISTS) {
+ m_snap_ids.insert(m_snap_ids.begin(), CEPH_NOSNAP);
+ object_map_locker.unlock();
+ snap_locker.unlock();
+ owner_locker.unlock();
+ return send_object_map();
+ }
+
+ bool may_update = false;
+ uint8_t new_state, current_state;
+
+ vector<ObjectRequest<> *>::reverse_iterator r_it = m_pending_requests.rbegin();
+ for (; r_it != m_pending_requests.rend(); ++r_it) {
+ ObjectRequest<> *req = *r_it;
+ if (!req->pre_object_map_update(&new_state)) {
+ continue;
+ }
+
+ current_state = (*m_ictx->object_map)[m_object_no];
+ ldout(cct, 20) << req->get_op_type() << " object no "
+ << m_object_no << " current state "
+ << stringify(static_cast<uint32_t>(current_state))
+ << " new state " << stringify(static_cast<uint32_t>(new_state))
+ << dendl;
+ may_update = true;
+ break;
+ }
+
+ if (may_update && (new_state != current_state) &&
+ m_ictx->object_map->aio_update<CopyupRequest>(
+ CEPH_NOSNAP, m_object_no, new_state, current_state, m_trace,
+ this)) {
+ return false;
+ }
+ }
+ }
+
+ return send_object_map();
+}
+
+bool CopyupRequest::send_object_map() {
+ // avoid possible recursive lock attempts
+ if (m_snap_ids.empty()) {
+ // no object map update required
+ return send_copyup();
+ } else {
+ // update object maps for HEAD and all existing snapshots
+ ldout(m_ictx->cct, 20) << "oid " << m_oid << dendl;
+ m_state = STATE_OBJECT_MAP;
+
+ RWLock::RLocker owner_locker(m_ictx->owner_lock);
+ AsyncObjectThrottle<>::ContextFactory context_factory(
+ boost::lambda::bind(boost::lambda::new_ptr<UpdateObjectMap>(),
+ boost::lambda::_1, m_ictx, m_object_no, &m_snap_ids, m_trace,
+ boost::lambda::_2));
+ AsyncObjectThrottle<> *throttle = new AsyncObjectThrottle<>(
+ NULL, *m_ictx, context_factory, util::create_context_callback(this),
+ NULL, 0, m_snap_ids.size());
+ throttle->start_ops(m_ictx->concurrent_management_ops);
+ }
+ return false;
+}
+
+} // namespace io
+} // namespace librbd
Code Review / stor4nfv.git / blobdiff