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Diffstat (limited to 'src/librbd/image/GetMetadataRequest.cc')
-rw-r--r-- | src/librbd/image/GetMetadataRequest.cc | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/src/librbd/image/GetMetadataRequest.cc b/src/librbd/image/GetMetadataRequest.cc new file mode 100644 index 000000000..1410c9005 --- /dev/null +++ b/src/librbd/image/GetMetadataRequest.cc @@ -0,0 +1,121 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +// vim: ts=8 sw=2 smarttab + +#include "librbd/image/GetMetadataRequest.h" +#include "cls/rbd/cls_rbd_client.h" +#include "common/dout.h" +#include "common/errno.h" +#include "include/ceph_assert.h" +#include "librbd/ImageCtx.h" +#include "librbd/Utils.h" +#include <boost/algorithm/string/predicate.hpp> + +#define dout_subsys ceph_subsys_rbd +#undef dout_prefix +#define dout_prefix *_dout << "librbd::image::GetMetadataRequest: " \ + << this << " " << __func__ << ": " + +#define MAX_KEYS 64U + +namespace librbd { +namespace image { +namespace { + +static const std::string INTERNAL_KEY_PREFIX{".rbd"}; + +} // anonymous namespace + +using util::create_rados_callback; + +template <typename I> +GetMetadataRequest<I>::GetMetadataRequest( + IoCtx &io_ctx, const std::string &oid, bool filter_internal, + const std::string& filter_key_prefix, const std::string& last_key, + uint32_t max_results, KeyValues* key_values, Context *on_finish) + : m_io_ctx(io_ctx), m_oid(oid), m_filter_internal(filter_internal), + m_filter_key_prefix(filter_key_prefix), m_last_key(last_key), + m_max_results(max_results), m_key_values(key_values), + m_on_finish(on_finish), + m_cct(reinterpret_cast<CephContext*>(m_io_ctx.cct())) { +} + +template <typename I> +void GetMetadataRequest<I>::send() { + metadata_list(); +} + +template <typename I> +void GetMetadataRequest<I>::metadata_list() { + ldout(m_cct, 15) << "start_key=" << m_last_key << dendl; + + m_expected_results = MAX_KEYS; + if (m_max_results > 0) { + m_expected_results = std::min<uint32_t>( + m_expected_results, m_max_results - m_key_values->size()); + } + + librados::ObjectReadOperation op; + cls_client::metadata_list_start(&op, m_last_key, m_expected_results); + + auto aio_comp = create_rados_callback< + GetMetadataRequest<I>, &GetMetadataRequest<I>::handle_metadata_list>(this); + m_out_bl.clear(); + m_io_ctx.aio_operate(m_oid, aio_comp, &op, &m_out_bl); + aio_comp->release(); +} + +template <typename I> +void GetMetadataRequest<I>::handle_metadata_list(int r) { + ldout(m_cct, 15) << "r=" << r << dendl; + + KeyValues metadata; + if (r == 0) { + auto it = m_out_bl.cbegin(); + r = cls_client::metadata_list_finish(&it, &metadata); + } + + if (r == -ENOENT || r == -EOPNOTSUPP) { + finish(0); + return; + } else if (r < 0) { + lderr(m_cct) << "failed to retrieve image metadata: " << cpp_strerror(r) + << dendl; + finish(r); + return; + } + + for (auto it = metadata.begin(); it != metadata.end(); ++it) { + if (m_filter_internal && + boost::starts_with(it->first, INTERNAL_KEY_PREFIX)) { + continue; + } else if (!m_filter_key_prefix.empty() && + !boost::starts_with(it->first, m_filter_key_prefix)) { + continue; + } + m_key_values->insert({it->first, std::move(it->second)}); + } + if (!metadata.empty()) { + m_last_key = metadata.rbegin()->first; + } + + if (metadata.size() == m_expected_results && + (m_max_results == 0 || m_key_values->size() < m_max_results)) { + metadata_list(); + return; + } + + finish(0); +} + +template <typename I> +void GetMetadataRequest<I>::finish(int r) { + ldout(m_cct, 15) << "r=" << r << dendl; + + m_on_finish->complete(r); + delete this; +} + +} // namespace image +} // namespace librbd + +template class librbd::image::GetMetadataRequest<librbd::ImageCtx>; |