Adding upstream version 18.2.2.upstream/18.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 287 insertions, 0 deletions

diff --git a/src/librbd/cache/ObjectCacherWriteback.cc b/src/librbd/cache/ObjectCacherWriteback.cc
new file mode 100644
index 000000000..97f2d46ba
--- /dev/null
+++ b/src/librbd/cache/ObjectCacherWriteback.cc
@@ -0,0 +1,287 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include <errno.h>
+
+#include "librbd/cache/ObjectCacherWriteback.h"
+#include "common/ceph_context.h"
+#include "common/dout.h"
+#include "common/ceph_mutex.h"
+#include "osdc/Striper.h"
+#include "include/Context.h"
+#include "include/neorados/RADOS.hpp"
+#include "include/rados/librados.hpp"
+#include "include/rbd/librbd.hpp"
+
+#include "librbd/ExclusiveLock.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/internal.h"
+#include "librbd/ObjectMap.h"
+#include "librbd/Journal.h"
+#include "librbd/Utils.h"
+#include "librbd/asio/ContextWQ.h"
+#include "librbd/io/AioCompletion.h"
+#include "librbd/io/ObjectDispatchSpec.h"
+#include "librbd/io/ObjectDispatcherInterface.h"
+#include "librbd/io/ReadResult.h"
+#include "librbd/io/Utils.h"
+
+#include "include/ceph_assert.h"
+
+#define dout_subsys ceph_subsys_rbd
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::cache::ObjectCacherWriteback: "
+
+using namespace std;
+
+namespace librbd {
+namespace cache {
+
+/**
+ * context to wrap another context in a Mutex
+ *
+ * @param cct cct
+ * @param c context to finish
+ * @param l mutex to lock
+ */
+class C_ReadRequest : public Context {
+public:
+  C_ReadRequest(CephContext *cct, Context *c, ceph::mutex *cache_lock)
+    : m_cct(cct), m_ctx(c), m_cache_lock(cache_lock) {
+  }
+  void finish(int r) override {
+    ldout(m_cct, 20) << "aio_cb completing " << dendl;
+    {
+      std::lock_guard cache_locker{*m_cache_lock};
+      m_ctx->complete(r);
+    }
+    ldout(m_cct, 20) << "aio_cb finished" << dendl;
+  }
+private:
+  CephContext *m_cct;
+  Context *m_ctx;
+  ceph::mutex *m_cache_lock;
+};
+
+class C_OrderedWrite : public Context {
+public:
+  C_OrderedWrite(CephContext *cct,
+                 ObjectCacherWriteback::write_result_d *result,
+                 const ZTracer::Trace &trace, ObjectCacherWriteback *wb)
+    : m_cct(cct), m_result(result), m_trace(trace), m_wb_handler(wb) {}
+  ~C_OrderedWrite() override {}
+  void finish(int r) override {
+    ldout(m_cct, 20) << "C_OrderedWrite completing " << m_result << dendl;
+    {
+      std::lock_guard l{m_wb_handler->m_lock};
+      ceph_assert(!m_result->done);
+      m_result->done = true;
+      m_result->ret = r;
+      m_wb_handler->complete_writes(m_result->oid);
+    }
+    ldout(m_cct, 20) << "C_OrderedWrite finished " << m_result << dendl;
+    m_trace.event("finish");
+  }
+private:
+  CephContext *m_cct;
+  ObjectCacherWriteback::write_result_d *m_result;
+  ZTracer::Trace m_trace;
+  ObjectCacherWriteback *m_wb_handler;
+};
+
+struct C_CommitIOEventExtent : public Context {
+  ImageCtx *image_ctx;
+  uint64_t journal_tid;
+  uint64_t offset;
+  uint64_t length;
+
+  C_CommitIOEventExtent(ImageCtx *image_ctx, uint64_t journal_tid,
+                        uint64_t offset, uint64_t length)
+    : image_ctx(image_ctx), journal_tid(journal_tid), offset(offset),
+      length(length) {
+  }
+
+  void finish(int r) override {
+    // all IO operations are flushed prior to closing the journal
+    ceph_assert(image_ctx->journal != nullptr);
+
+    image_ctx->journal->commit_io_event_extent(journal_tid, offset, length, r);
+  }
+};
+
+ObjectCacherWriteback::ObjectCacherWriteback(ImageCtx *ictx, ceph::mutex& lock)
+  : m_tid(0), m_lock(lock), m_ictx(ictx) {
+}
+
+void ObjectCacherWriteback::read(const object_t& oid, uint64_t object_no,
+                                 const object_locator_t& oloc,
+                                 uint64_t off, uint64_t len, snapid_t snapid,
+                                 bufferlist *pbl, uint64_t trunc_size,
+                                 __u32 trunc_seq, int op_flags,
+                                 const ZTracer::Trace &parent_trace,
+                                 Context *onfinish)
+{
+  ZTracer::Trace trace;
+  if (parent_trace.valid()) {
+    trace.init("", &m_ictx->trace_endpoint, &parent_trace);
+    trace.copy_name("cache read " + oid.name);
+    trace.event("start");
+  }
+
+  // on completion, take the mutex and then call onfinish.
+  onfinish = new C_ReadRequest(m_ictx->cct, onfinish, &m_lock);
+
+  // re-use standard object read state machine
+  auto aio_comp = io::AioCompletion::create_and_start(onfinish, m_ictx,
+                                                      io::AIO_TYPE_READ);
+  aio_comp->read_result = io::ReadResult{pbl};
+  aio_comp->set_request_count(1);
+
+  auto req_comp = new io::ReadResult::C_ObjectReadRequest(
+    aio_comp, {{off, len, {{0, len}}}});
+
+  auto io_context = m_ictx->duplicate_data_io_context();
+  if (snapid != CEPH_NOSNAP) {
+    io_context->read_snap(snapid);
+  }
+
+  // extract the embedded RBD read flags from the op_flags
+  int read_flags = (op_flags & READ_FLAGS_MASK) >> READ_FLAGS_SHIFT;
+  op_flags &= ~READ_FLAGS_MASK;
+
+  auto req = io::ObjectDispatchSpec::create_read(
+    m_ictx, io::OBJECT_DISPATCH_LAYER_CACHE, object_no, &req_comp->extents,
+    io_context, op_flags, read_flags, trace, nullptr, req_comp);
+  req->send();
+}
+
+bool ObjectCacherWriteback::may_copy_on_write(const object_t& oid,
+                                              uint64_t read_off,
+                                              uint64_t read_len,
+                                              snapid_t snapid)
+{
+  std::shared_lock image_locker(m_ictx->image_lock);
+  uint64_t raw_overlap = 0;
+  uint64_t object_overlap = 0;
+  m_ictx->get_parent_overlap(m_ictx->snap_id, &raw_overlap);
+  if (raw_overlap > 0) {
+    uint64_t object_no = oid_to_object_no(oid.name, m_ictx->object_prefix);
+    auto [parent_extents, area] = io::util::object_to_area_extents(
+        m_ictx, object_no, {{0, m_ictx->layout.object_size}});
+    object_overlap = m_ictx->prune_parent_extents(parent_extents, area,
+                                                  raw_overlap, false);
+  }
+  bool may = object_overlap > 0;
+  ldout(m_ictx->cct, 10) << "may_copy_on_write " << oid << " " << read_off
+                         << "~" << read_len << " = " << may << dendl;
+  return may;
+}
+
+ceph_tid_t ObjectCacherWriteback::write(const object_t& oid,
+                                        const object_locator_t& oloc,
+                                        uint64_t off, uint64_t len,
+                                        const SnapContext& snapc,
+                                        const bufferlist &bl,
+                                        ceph::real_time mtime,
+                                        uint64_t trunc_size,
+                                        __u32 trunc_seq, ceph_tid_t journal_tid,
+                                        const ZTracer::Trace &parent_trace,
+                                        Context *oncommit)
+{
+  ZTracer::Trace trace;
+  if (parent_trace.valid()) {
+    trace.init("", &m_ictx->trace_endpoint, &parent_trace);
+    trace.copy_name("writeback " + oid.name);
+    trace.event("start");
+  }
+
+  uint64_t object_no = oid_to_object_no(oid.name, m_ictx->object_prefix);
+
+  write_result_d *result = new write_result_d(oid.name, oncommit);
+  m_writes[oid.name].push(result);
+  ldout(m_ictx->cct, 20) << "write will wait for result " << result << dendl;
+
+  bufferlist bl_copy(bl);
+
+  Context *ctx = new C_OrderedWrite(m_ictx->cct, result, trace, this);
+  ctx = util::create_async_context_callback(*m_ictx, ctx);
+
+  auto io_context = m_ictx->duplicate_data_io_context();
+  if (!snapc.empty()) {
+    io_context->write_snap_context(
+      {{snapc.seq, {snapc.snaps.begin(), snapc.snaps.end()}}});
+  }
+
+  auto req = io::ObjectDispatchSpec::create_write(
+    m_ictx, io::OBJECT_DISPATCH_LAYER_CACHE, object_no, off, std::move(bl_copy),
+    io_context, 0, 0, std::nullopt, journal_tid, trace, ctx);
+  req->object_dispatch_flags = (
+    io::OBJECT_DISPATCH_FLAG_FLUSH |
+    io::OBJECT_DISPATCH_FLAG_WILL_RETRY_ON_ERROR);
+  req->send();
+
+  return ++m_tid;
+}
+
+
+void ObjectCacherWriteback::overwrite_extent(const object_t& oid, uint64_t off,
+                                             uint64_t len,
+                                             ceph_tid_t original_journal_tid,
+                                             ceph_tid_t new_journal_tid) {
+  ldout(m_ictx->cct, 20) << __func__ << ": " << oid << " "
+                         << off << "~" << len << " "
+                         << "journal_tid=" << original_journal_tid << ", "
+                         << "new_journal_tid=" << new_journal_tid << dendl;
+
+  uint64_t object_no = oid_to_object_no(oid.name, m_ictx->object_prefix);
+
+  // all IO operations are flushed prior to closing the journal
+  ceph_assert(original_journal_tid != 0 && m_ictx->journal != NULL);
+
+  auto [image_extents, _] = io::util::object_to_area_extents(m_ictx, object_no,
+                                                             {{off, len}});
+  for (auto it = image_extents.begin(); it != image_extents.end(); ++it) {
+    if (new_journal_tid != 0) {
+      // ensure new journal event is safely committed to disk before
+      // committing old event
+      m_ictx->journal->flush_event(
+        new_journal_tid, new C_CommitIOEventExtent(m_ictx,
+                                                   original_journal_tid,
+                                                   it->first, it->second));
+    } else {
+      m_ictx->journal->commit_io_event_extent(original_journal_tid, it->first,
+                                              it->second, 0);
+    }
+  }
+}
+
+void ObjectCacherWriteback::complete_writes(const std::string& oid)
+{
+  ceph_assert(ceph_mutex_is_locked(m_lock));
+  std::queue<write_result_d*>& results = m_writes[oid];
+  ldout(m_ictx->cct, 20) << "complete_writes() oid " << oid << dendl;
+  std::list<write_result_d*> finished;
+
+  while (!results.empty()) {
+    write_result_d *result = results.front();
+    if (!result->done)
+      break;
+    finished.push_back(result);
+    results.pop();
+  }
+
+  if (results.empty())
+    m_writes.erase(oid);
+
+  for (std::list<write_result_d*>::iterator it = finished.begin();
+       it != finished.end(); ++it) {
+    write_result_d *result = *it;
+    ldout(m_ictx->cct, 20) << "complete_writes() completing " << result
+                           << dendl;
+    result->oncommit->complete(result->ret);
+    delete result;
+  }
+}
+
+} // namespace cache
+} // namespace librbd