+++ /dev/null
-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-// vim: ts=8 sw=2 smarttab
-
-#include "librbd/io/ReadResult.h"
-#include "include/buffer.h"
-#include "common/dout.h"
-#include "librbd/io/AioCompletion.h"
-#include <boost/variant/apply_visitor.hpp>
-#include <boost/variant/static_visitor.hpp>
-
-#define dout_subsys ceph_subsys_rbd
-#undef dout_prefix
-#define dout_prefix *_dout << "librbd::io::ReadResult: " << this \
- << " " << __func__ << ": "
-
-namespace librbd {
-namespace io {
-
-struct ReadResult::SetClipLengthVisitor : public boost::static_visitor<void> {
- size_t length;
-
- SetClipLengthVisitor(size_t length) : length(length) {
- }
-
- void operator()(Linear &linear) const {
- assert(length <= linear.buf_len);
- linear.buf_len = length;
- }
-
- template <typename T>
- void operator()(T &t) const {
- }
-};
-
-struct ReadResult::AssembleResultVisitor : public boost::static_visitor<void> {
- CephContext *cct;
- Striper::StripedReadResult &destriper;
-
- AssembleResultVisitor(CephContext *cct, Striper::StripedReadResult &destriper)
- : cct(cct), destriper(destriper) {
- }
-
- void operator()(Empty &empty) const {
- ldout(cct, 20) << "dropping read result" << dendl;
- }
-
- void operator()(Linear &linear) const {
- ldout(cct, 20) << "copying resulting bytes to "
- << reinterpret_cast<void*>(linear.buf) << dendl;
- destriper.assemble_result(cct, linear.buf, linear.buf_len);
- }
-
- void operator()(Vector &vector) const {
- bufferlist bl;
- destriper.assemble_result(cct, bl, true);
-
- ldout(cct, 20) << "copying resulting " << bl.length() << " bytes to iovec "
- << reinterpret_cast<const void*>(vector.iov) << dendl;
-
- bufferlist::iterator it = bl.begin();
- size_t length = bl.length();
- size_t offset = 0;
- int idx = 0;
- for (; offset < length && idx < vector.iov_count; idx++) {
- size_t len = MIN(vector.iov[idx].iov_len, length - offset);
- it.copy(len, static_cast<char *>(vector.iov[idx].iov_base));
- offset += len;
- }
- assert(offset == bl.length());
- }
-
- void operator()(Bufferlist &bufferlist) const {
- bufferlist.bl->clear();
- destriper.assemble_result(cct, *bufferlist.bl, true);
-
- ldout(cct, 20) << "moved resulting " << bufferlist.bl->length() << " "
- << "bytes to bl " << reinterpret_cast<void*>(bufferlist.bl)
- << dendl;
- }
-};
-
-ReadResult::C_ReadRequest::C_ReadRequest(AioCompletion *aio_completion)
- : aio_completion(aio_completion) {
- aio_completion->add_request();
-}
-
-void ReadResult::C_ReadRequest::finish(int r) {
- aio_completion->complete_request(r);
-}
-
-void ReadResult::C_ImageReadRequest::finish(int r) {
- CephContext *cct = aio_completion->ictx->cct;
- ldout(cct, 10) << "C_ImageReadRequest: r=" << r
- << dendl;
- if (r >= 0) {
- size_t length = 0;
- for (auto &image_extent : image_extents) {
- length += image_extent.second;
- }
- assert(length == bl.length());
-
- aio_completion->lock.Lock();
- aio_completion->read_result.m_destriper.add_partial_result(
- cct, bl, image_extents);
- aio_completion->lock.Unlock();
- r = length;
- }
-
- C_ReadRequest::finish(r);
-}
-
-void ReadResult::C_SparseReadRequestBase::finish(ExtentMap &extent_map,
- const Extents &buffer_extents,
- uint64_t offset, size_t length,
- bufferlist &bl, int r) {
- aio_completion->lock.Lock();
- CephContext *cct = aio_completion->ictx->cct;
- ldout(cct, 10) << "C_SparseReadRequestBase: r = " << r
- << dendl;
-
- if (r >= 0 || r == -ENOENT) { // this was a sparse_read operation
- ldout(cct, 10) << " got " << extent_map
- << " for " << buffer_extents
- << " bl " << bl.length() << dendl;
- // reads from the parent don't populate the m_ext_map and the overlap
- // may not be the full buffer. compensate here by filling in m_ext_map
- // with the read extent when it is empty.
- if (extent_map.empty()) {
- extent_map[offset] = bl.length();
- }
-
- aio_completion->read_result.m_destriper.add_partial_sparse_result(
- cct, bl, extent_map, offset, buffer_extents);
- r = length;
- }
- aio_completion->lock.Unlock();
-
- C_ReadRequest::finish(r);
-}
-
-ReadResult::ReadResult() : m_buffer(Empty()) {
-}
-
-ReadResult::ReadResult(char *buf, size_t buf_len)
- : m_buffer(Linear(buf, buf_len)) {
-}
-
-ReadResult::ReadResult(const struct iovec *iov, int iov_count)
- : m_buffer(Vector(iov, iov_count)) {
-}
-
-ReadResult::ReadResult(ceph::bufferlist *bl)
- : m_buffer(Bufferlist(bl)) {
-}
-
-void ReadResult::set_clip_length(size_t length) {
- boost::apply_visitor(SetClipLengthVisitor(length), m_buffer);
-}
-
-void ReadResult::assemble_result(CephContext *cct) {
- boost::apply_visitor(AssembleResultVisitor(cct, m_destriper), m_buffer);
-}
-
-} // namespace io
-} // namespace librbd
-