1 files changed, 133 insertions, 0 deletions
diff --git a/src/librbd/migration/Utils.cc b/src/librbd/migration/Utils.cc
new file mode 100644
index 000000000..c5c1279d8
--- /dev/null
+++ b/src/librbd/migration/Utils.cc
@@ -0,0 +1,133 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/migration/Utils.h"
+#include "common/dout.h"
+#include "common/errno.h"
+#include <boost/lexical_cast.hpp>
+#include <regex>
+
+namespace librbd {
+namespace migration {
+namespace util {
+
+#define dout_subsys ceph_subsys_rbd
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::migration::util::" << __func__ << ": "
+
+int parse_url(CephContext* cct, const std::string& url, UrlSpec* url_spec) {
+  ldout(cct, 10) << "url=" << url << dendl;
+  *url_spec = UrlSpec{};
+
+  // parse the provided URL (scheme, user, password, host, port, path,
+  // parameters, query, and fragment)
+  std::regex url_regex(
+    R"(^(?:([^:/]*)://)?(?:(\w+)(?::(\w+))?@)?([^/;\?:#]+)(?::([^/;\?#]+))?)"
+    R"((?:/([^;\?#]*))?(?:;([^\?#]+))?(?:\?([^#]+))?(?:#(\w+))?$)");
+  std::smatch match;
+  if(!std::regex_match(url, match, url_regex)) {
+    lderr(cct) << "invalid url: '" << url << "'" << dendl;
+    return -EINVAL;
+  }
+
+  auto& scheme = match[1];
+  if (scheme == "http" || scheme == "") {
+    url_spec->scheme = URL_SCHEME_HTTP;
+  } else if (scheme == "https") {
+    url_spec->scheme = URL_SCHEME_HTTPS;
+    url_spec->port = "443";
+  } else {
+    lderr(cct) << "invalid url scheme: '" << url << "'" << dendl;
+    return -EINVAL;
+  }
+
+  url_spec->host = match[4];
+  auto& port = match[5];
+  if (port.matched) {
+    try {
+      boost::lexical_cast<uint16_t>(port);
+    } catch (boost::bad_lexical_cast&) {
+      lderr(cct) << "invalid url port: '" << url << "'" << dendl;
+      return -EINVAL;
+    }
+    url_spec->port = port;
+  }
+
+  auto& path = match[6];
+  if (path.matched) {
+    url_spec->path += path;
+  }
+  return 0;
+}
+
+void zero_shrunk_snapshot(CephContext* cct, const io::Extents& image_extents,
+                          uint64_t snap_id, uint64_t new_size,
+                          std::optional<uint64_t> *previous_size,
+                          io::SparseExtents* sparse_extents) {
+  if (*previous_size && **previous_size > new_size) {
+    ldout(cct, 20) << "snapshot resize " << **previous_size << " -> "
+                   << new_size << dendl;
+    interval_set<uint64_t> zero_interval;
+    zero_interval.insert(new_size, **previous_size - new_size);
+
+    for (auto& image_extent : image_extents) {
+      interval_set<uint64_t> image_interval;
+      image_interval.insert(image_extent.first, image_extent.second);
+
+      image_interval.intersection_of(zero_interval);
+      for (auto [image_offset, image_length] : image_interval) {
+        ldout(cct, 20) << "zeroing extent " << image_offset << "~"
+                       << image_length << " at snapshot " << snap_id << dendl;
+        sparse_extents->insert(image_offset, image_length,
+                               {io::SPARSE_EXTENT_STATE_ZEROED, image_length});
+      }
+    }
+  }
+  *previous_size = new_size;
+}
+
+void merge_snapshot_delta(const io::SnapIds& snap_ids,
+                          io::SnapshotDelta* snapshot_delta) {
+  io::SnapshotDelta orig_snapshot_delta = std::move(*snapshot_delta);
+  snapshot_delta->clear();
+
+  auto snap_id_it = snap_ids.begin();
+  ceph_assert(snap_id_it != snap_ids.end());
+
+  // merge any snapshot intervals that were not requested
+  std::list<io::SparseExtents*> pending_sparse_extents;
+  for (auto& [snap_key, sparse_extents] : orig_snapshot_delta) {
+    // advance to next valid requested snap id
+    while (snap_id_it != snap_ids.end() && *snap_id_it < snap_key.first) {
+      ++snap_id_it;
+    }
+    if (snap_id_it == snap_ids.end()) {
+      break;
+    }
+
+    // loop through older write/read snapshot sparse extents to remove any
+    // overlaps with the current sparse extent
+    for (auto prev_sparse_extents : pending_sparse_extents) {
+      for (auto& sparse_extent : sparse_extents) {
+        prev_sparse_extents->erase(sparse_extent.get_off(),
+                                   sparse_extent.get_len());
+      }
+    }
+
+    auto write_read_snap_ids = std::make_pair(*snap_id_it, snap_key.second);
+    (*snapshot_delta)[write_read_snap_ids] = std::move(sparse_extents);
+
+    if (write_read_snap_ids.first > snap_key.first) {
+      // the current snapshot wasn't requested so it might need to get
+      // merged with a later snapshot
+      pending_sparse_extents.push_back(&(*snapshot_delta)[write_read_snap_ids]);
+    } else {
+      // we don't merge results passed a valid requested snapshot
+      pending_sparse_extents.clear();
+    }
+  }
+}
+
+} // namespace util
+} // namespace migration
+} // namespace librbd