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// -*- 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>;
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