1 files changed, 106 insertions, 0 deletions
diff --git a/src/librbd/cache/pwl/rwl/LogEntry.cc b/src/librbd/cache/pwl/rwl/LogEntry.cc
new file mode 100644
index 000000000..38e09c22a
--- /dev/null
+++ b/src/librbd/cache/pwl/rwl/LogEntry.cc
@@ -0,0 +1,106 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/cache/ImageWriteback.h"
+#include "LogEntry.h"
+
+#define dout_subsys ceph_subsys_rbd_pwl
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::cache::pwl::rwl::WriteLogEntry: " \
+                           << this << " " <<  __func__ << ": "
+
+namespace librbd {
+namespace cache {
+namespace pwl {
+namespace rwl {
+
+void WriteLogEntry::writeback(
+    librbd::cache::ImageWritebackInterface &image_writeback, Context *ctx) {
+  /* Pass a copy of the pmem buffer to ImageWriteback (which may hang on to the
+   * bl even after flush()). */
+  bufferlist entry_bl;
+  buffer::list entry_bl_copy;
+  copy_cache_bl(&entry_bl_copy);
+  entry_bl_copy.begin(0).copy(write_bytes(), entry_bl);
+  image_writeback.aio_write({{ram_entry.image_offset_bytes,
+                              ram_entry.write_bytes}},
+                            std::move(entry_bl), 0, ctx);
+}
+
+void WriteLogEntry::init_cache_bp() {
+  ceph_assert(!this->cache_bp.have_raw());
+  cache_bp = buffer::ptr(buffer::create_static(this->write_bytes(),
+                                               (char*)this->cache_buffer));
+}
+
+void WriteLogEntry::init_bl(buffer::ptr &bp, buffer::list &bl) {
+  if(!is_writesame) {
+    bl.append(bp);
+    return;
+  }
+  for (uint64_t i = 0; i < ram_entry.write_bytes / ram_entry.ws_datalen; i++) {
+    bl.append(bp);
+  }
+  int trailing_partial = ram_entry.write_bytes % ram_entry.ws_datalen;
+  if (trailing_partial) {
+    bl.append(bp, 0, trailing_partial);
+  }
+}
+
+void WriteLogEntry::init_cache_buffer(
+    std::vector<WriteBufferAllocation>::iterator allocation) {
+  this->ram_entry.write_data = allocation->buffer_oid;
+  ceph_assert(!TOID_IS_NULL(this->ram_entry.write_data));
+  cache_buffer = D_RW(this->ram_entry.write_data);
+}
+
+buffer::list& WriteLogEntry::get_cache_bl() {
+  if (0 == bl_refs) {
+    std::lock_guard locker(m_entry_bl_lock);
+    if (0 == bl_refs) {
+      //init pmem bufferlist
+      cache_bl.clear();
+      init_cache_bp();
+      ceph_assert(cache_bp.have_raw());
+      int before_bl = cache_bp.raw_nref();
+      this->init_bl(cache_bp, cache_bl);
+      int after_bl = cache_bp.raw_nref();
+      bl_refs = after_bl - before_bl;
+    }
+    ceph_assert(0 != bl_refs);
+  }
+  return cache_bl;
+}
+
+void WriteLogEntry::copy_cache_bl(bufferlist *out_bl) {
+  this->get_cache_bl();
+  // cache_bp is now initialized
+  ceph_assert(cache_bp.length() == cache_bp.raw_length());
+  buffer::ptr cloned_bp = cache_bp.begin_deep().get_ptr(cache_bp.length());
+  out_bl->clear();
+  this->init_bl(cloned_bp, *out_bl);
+}
+
+unsigned int WriteLogEntry::reader_count() const {
+  if (cache_bp.have_raw()) {
+    return (cache_bp.raw_nref() - bl_refs - 1);
+  } else {
+    return 0;
+  }
+}
+
+void WriteSameLogEntry::writeback(
+    librbd::cache::ImageWritebackInterface &image_writeback, Context *ctx) {
+  bufferlist entry_bl;
+  buffer::list entry_bl_copy;
+  copy_cache_bl(&entry_bl_copy);
+  entry_bl_copy.begin(0).copy(write_bytes(), entry_bl);
+  image_writeback.aio_writesame(ram_entry.image_offset_bytes,
+                                ram_entry.write_bytes,
+                                std::move(entry_bl), 0, ctx);
+}
+
+} // namespace rwl
+} // namespace pwl
+} // namespace cache
+} // namespace librbd