1 files changed, 154 insertions, 0 deletions
diff --git a/src/librbd/io/ImageDispatchSpec.cc b/src/librbd/io/ImageDispatchSpec.cc
new file mode 100644
index 00000000..2c405d74
--- /dev/null
+++ b/src/librbd/io/ImageDispatchSpec.cc
@@ -0,0 +1,154 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/io/ImageDispatchSpec.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/io/AioCompletion.h"
+#include "librbd/io/ImageRequest.h"
+#include <boost/variant.hpp>
+
+namespace librbd {
+namespace io {
+
+template <typename I>
+struct ImageDispatchSpec<I>::SendVisitor
+  : public boost::static_visitor<void> {
+  ImageDispatchSpec* spec;
+
+  explicit SendVisitor(ImageDispatchSpec* spec)
+    : spec(spec) {
+  }
+
+  void operator()(Read& read) const {
+    ImageRequest<I>::aio_read(
+      &spec->m_image_ctx, spec->m_aio_comp, std::move(spec->m_image_extents),
+      std::move(read.read_result), spec->m_op_flags, spec->m_parent_trace);
+  }
+
+  void operator()(Discard& discard) const {
+    ImageRequest<I>::aio_discard(
+      &spec->m_image_ctx, spec->m_aio_comp, std::move(spec->m_image_extents),
+      discard.discard_granularity_bytes, spec->m_parent_trace);
+  }
+
+  void operator()(Write& write) const {
+    ImageRequest<I>::aio_write(
+      &spec->m_image_ctx, spec->m_aio_comp, std::move(spec->m_image_extents),
+      std::move(write.bl), spec->m_op_flags, spec->m_parent_trace);
+  }
+
+  void operator()(WriteSame& write_same) const {
+    ImageRequest<I>::aio_writesame(
+      &spec->m_image_ctx, spec->m_aio_comp, std::move(spec->m_image_extents),
+      std::move(write_same.bl), spec->m_op_flags, spec->m_parent_trace);
+  }
+
+  void operator()(CompareAndWrite& compare_and_write) const {
+    ImageRequest<I>::aio_compare_and_write(
+      &spec->m_image_ctx, spec->m_aio_comp, std::move(spec->m_image_extents),
+      std::move(compare_and_write.cmp_bl), std::move(compare_and_write.bl),
+      compare_and_write.mismatch_offset, spec->m_op_flags,
+      spec->m_parent_trace);
+  }
+
+  void operator()(Flush& flush) const {
+    ImageRequest<I>::aio_flush(
+      &spec->m_image_ctx, spec->m_aio_comp, flush.flush_source,
+      spec->m_parent_trace);
+  }
+};
+
+template <typename I>
+struct ImageDispatchSpec<I>::IsWriteOpVisitor
+  : public boost::static_visitor<bool> {
+  bool operator()(const Read&) const {
+    return false;
+  }
+
+  template <typename T>
+  bool operator()(const T&) const {
+    return true;
+  }
+};
+
+template <typename I>
+struct ImageDispatchSpec<I>::TokenRequestedVisitor
+  : public boost::static_visitor<uint64_t> {
+  ImageDispatchSpec* spec;
+  uint64_t flag;
+  uint64_t *tokens;
+
+  TokenRequestedVisitor(ImageDispatchSpec* spec, uint64_t _flag,
+                        uint64_t *tokens)
+    : spec(spec), flag(_flag), tokens(tokens) {
+  }
+
+  uint64_t operator()(const Read&) const {
+    if (flag & RBD_QOS_WRITE_MASK) {
+      *tokens = 0;
+      return false;
+    }
+
+    *tokens = (flag & RBD_QOS_BPS_MASK) ? spec->extents_length() : 1;
+    return true;
+  }
+
+  uint64_t operator()(const Flush&) const {
+    *tokens = 0;
+    return true;
+  }
+
+  template <typename T>
+  uint64_t operator()(const T&) const {
+    if (flag & RBD_QOS_READ_MASK) {
+      *tokens = 0;
+      return false;
+    }
+
+    *tokens = (flag & RBD_QOS_BPS_MASK) ? spec->extents_length() : 1;
+    return true;
+  }
+};
+
+template <typename I>
+void ImageDispatchSpec<I>::send() {
+  boost::apply_visitor(SendVisitor{this}, m_request);
+}
+
+template <typename I>
+void ImageDispatchSpec<I>::fail(int r) {
+  m_aio_comp->get();
+  m_aio_comp->fail(r);
+}
+
+template <typename I>
+uint64_t ImageDispatchSpec<I>::extents_length() {
+  uint64_t length = 0;
+  auto &extents = this->m_image_extents;
+
+  for (auto &extent : extents) {
+    length += extent.second;
+  }
+  return length;
+}
+
+template <typename I>
+bool ImageDispatchSpec<I>::is_write_op() const {
+  return boost::apply_visitor(IsWriteOpVisitor(), m_request);
+}
+
+template <typename I>
+bool ImageDispatchSpec<I>::tokens_requested(uint64_t flag, uint64_t *tokens) {
+  return boost::apply_visitor(TokenRequestedVisitor{this, flag, tokens},
+                              m_request);
+}
+
+template <typename I>
+void ImageDispatchSpec<I>::start_op() {
+  m_aio_comp->start_op();
+}
+
+} // namespace io
+} // namespace librbd
+
+template class librbd::io::ImageDispatchSpec<librbd::ImageCtx>;