librbd: initial set of changes to migration API for instant-restore

src/cls/rbd/cls_rbd_types.cc

@@ -1219,7 +1219,12 @@ std::ostream& operator<<(std::ostream& os,
 }
 
 void MigrationSpec::encode(bufferlist& bl) const {
-  ENCODE_START(2, 1, bl);
+  uint8_t min_version = 1;
+  if (!source_spec.empty()) {
+    min_version = 3;
+  }
+
+  ENCODE_START(3, min_version, bl);
   encode(header_type, bl);
   encode(pool_id, bl);
   encode(pool_namespace, bl);
@@ -1232,11 +1237,12 @@ void MigrationSpec::encode(bufferlist& bl) const {
   encode(state, bl);
   encode(state_description, bl);
   encode(static_cast<uint8_t>(mirror_image_mode), bl);
+  encode(source_spec, bl);
   ENCODE_FINISH(bl);
 }
 
 void MigrationSpec::decode(bufferlist::const_iterator& bl) {
-  DECODE_START(2, bl);
+  DECODE_START(3, bl);
   decode(header_type, bl);
   decode(pool_id, bl);
   decode(pool_namespace, bl);
@@ -1253,7 +1259,10 @@ void MigrationSpec::decode(bufferlist::const_iterator& bl) {
     decode(int_mode, bl);
     mirror_image_mode = static_cast<MirrorImageMode>(int_mode);
   }
- DECODE_FINISH(bl);
+  if (struct_v >= 3) {
+    decode(source_spec, bl);
+  }
+  DECODE_FINISH(bl);
 }
 
 std::ostream& operator<<(std::ostream& os,
@@ -1270,10 +1279,15 @@ std::ostream& operator<<(std::ostream& os,
 
 void MigrationSpec::dump(Formatter *f) const {
   f->dump_stream("header_type") << header_type;
-  f->dump_int("pool_id", pool_id);
-  f->dump_string("pool_namespace", pool_namespace);
-  f->dump_string("image_name", image_name);
-  f->dump_string("image_id", image_id);
+  if (header_type == MIGRATION_HEADER_TYPE_SRC ||
+      source_spec.empty()) {
+    f->dump_int("pool_id", pool_id);
+    f->dump_string("pool_namespace", pool_namespace);
+    f->dump_string("image_name", image_name);
+    f->dump_string("image_id", image_id);
+  } else {
+    f->dump_string("source_spec", source_spec);
+  }
   f->dump_stream("snap_seqs") << snap_seqs;
   f->dump_unsigned("overlap", overlap);
   f->dump_bool("mirroring", mirroring);
@@ -1283,20 +1297,29 @@ void MigrationSpec::dump(Formatter *f) const {
 void MigrationSpec::generate_test_instances(std::list<MigrationSpec*> &o) {
   o.push_back(new MigrationSpec());
   o.push_back(new MigrationSpec(MIGRATION_HEADER_TYPE_SRC, 1, "ns",
-                                "image_name", "image_id", {{1, 2}}, 123, true,
-                                MIRROR_IMAGE_MODE_SNAPSHOT, true,
+                                "image_name", "image_id", "", {{1, 2}}, 123,
+                                true, MIRROR_IMAGE_MODE_SNAPSHOT, true,
+                                MIGRATION_STATE_PREPARED, "description"));
+  o.push_back(new MigrationSpec(MIGRATION_HEADER_TYPE_DST, -1, "", "", "",
+                                "{\"format\": \"raw\"}", {{1, 2}}, 123,
+                                true, MIRROR_IMAGE_MODE_SNAPSHOT, true,
                                 MIGRATION_STATE_PREPARED, "description"));
 }
 
 std::ostream& operator<<(std::ostream& os,
                          const MigrationSpec& migration_spec) {
   os << "["
-     << "header_type=" << migration_spec.header_type << ", "
-     << "pool_id=" << migration_spec.pool_id << ", "
-     << "pool_namespace=" << migration_spec.pool_namespace << ", "
-     << "image_name=" << migration_spec.image_name << ", "
-     << "image_id=" << migration_spec.image_id << ", "
-     << "snap_seqs=" << migration_spec.snap_seqs << ", "
+     << "header_type=" << migration_spec.header_type << ", ";
+  if (migration_spec.header_type == MIGRATION_HEADER_TYPE_SRC ||
+      migration_spec.source_spec.empty()) {
+    os << "pool_id=" << migration_spec.pool_id << ", "
+       << "pool_namespace=" << migration_spec.pool_namespace << ", "
+       << "image_name=" << migration_spec.image_name << ", "
+       << "image_id=" << migration_spec.image_id << ", ";
+  } else {
+     os << "source_spec=" << migration_spec.source_spec << ", ";
+  }
+  os << "snap_seqs=" << migration_spec.snap_seqs << ", "
      << "overlap=" << migration_spec.overlap << ", "
      << "flatten=" << migration_spec.flatten << ", "
      << "mirroring=" << migration_spec.mirroring << ", "

src/cls/rbd/cls_rbd_types.h

@@ -950,6 +950,7 @@ struct MigrationSpec {
   std::string pool_namespace;
   std::string image_name;
   std::string image_id;
+  std::string source_spec;
   std::map<uint64_t, uint64_t> snap_seqs;
   uint64_t overlap = 0;
   bool flatten = false;
@@ -962,14 +963,15 @@ struct MigrationSpec {
   }
   MigrationSpec(MigrationHeaderType header_type, int64_t pool_id,
                 const std::string& pool_namespace,
-                const std::string &image_name, const std::string &image_id,
+                const std::string& image_name, const std::string &image_id,
+                const std::string& source_spec,
                 const std::map<uint64_t, uint64_t> &snap_seqs, uint64_t overlap,
                 bool mirroring, MirrorImageMode mirror_image_mode, bool flatten,
                 MigrationState state, const std::string &state_description)
     : header_type(header_type), pool_id(pool_id),
       pool_namespace(pool_namespace), image_name(image_name),
-      image_id(image_id), snap_seqs(snap_seqs), overlap(overlap),
-      flatten(flatten), mirroring(mirroring),
+      image_id(image_id), source_spec(source_spec), snap_seqs(snap_seqs),
+      overlap(overlap), flatten(flatten), mirroring(mirroring),
       mirror_image_mode(mirror_image_mode), state(state),
       state_description(state_description) {
   }
@@ -983,10 +985,11 @@ struct MigrationSpec {
   inline bool operator==(const MigrationSpec& ms) const {
     return header_type == ms.header_type && pool_id == ms.pool_id &&
       pool_namespace == ms.pool_namespace && image_name == ms.image_name &&
-      image_id == ms.image_id && snap_seqs == ms.snap_seqs &&
-      overlap == ms.overlap && flatten == ms.flatten &&
-      mirroring == ms.mirroring && mirror_image_mode == ms.mirror_image_mode &&
-      state == ms.state && state_description == ms.state_description;
+      image_id == ms.image_id && source_spec == ms.source_spec &&
+      snap_seqs == ms.snap_seqs && overlap == ms.overlap &&
+      flatten == ms.flatten && mirroring == ms.mirroring &&
+      mirror_image_mode == ms.mirror_image_mode && state == ms.state &&
+      state_description == ms.state_description;
   }
 };
 

src/include/rbd/librbd.h

@@ -726,6 +726,10 @@ CEPH_RBD_API int rbd_get_parent(rbd_image_t image,
                                 rbd_linked_image_spec_t *parent_image,
                                 rbd_snap_spec_t *parent_snap);
 
+CEPH_RBD_API int rbd_get_migration_source_spec(rbd_image_t image,
+                                               char* source_spec,
+                                               size_t* max_len);
+
 CEPH_RBD_API int rbd_get_flags(rbd_image_t image, uint64_t *flags);
 CEPH_RBD_API int rbd_get_group(rbd_image_t image, rbd_group_info_t *group_info,
                                size_t group_info_size);

src/include/rbd/librbd.hpp

@@ -528,6 +528,8 @@ class CEPH_RBD_API Image
       CEPH_RBD_DEPRECATED;
   int get_parent(linked_image_spec_t *parent_image, snap_spec_t *parent_snap);
 
+  int get_migration_source_spec(std::string* source_spec);
+
   int old_format(uint8_t *old);
   int size(uint64_t *size);
   int get_group(group_info_t *group_info, size_t group_info_size);

src/librbd/CMakeLists.txt

@@ -116,6 +116,11 @@ set(librbd_internal_srcs
   managed_lock/ReacquireRequest.cc
   managed_lock/ReleaseRequest.cc
   managed_lock/Utils.cc
+  migration/FileStream.cc
+  migration/ImageDispatch.cc
+  migration/NativeFormat.cc
+  migration/OpenSourceImageRequest.cc
+  migration/RawFormat.cc
   mirror/DemoteRequest.cc
   mirror/DisableRequest.cc
   mirror/EnableRequest.cc

src/librbd/ImageCtx.cc

@@ -121,6 +121,10 @@ librados::IoCtx duplicate_io_ctx(librados::IoCtx& io_ctx) {
       asok_hook(nullptr),
       trace_endpoint("librbd")
   {
+    ldout(cct, 10) << this << " " << __func__ << ": "
+                   << "image_name=" << image_name << ", "
+                   << "image_id=" << image_id << dendl;
+
     if (snap)
       snap_name = snap;
 
@@ -147,6 +151,8 @@ librados::IoCtx duplicate_io_ctx(librados::IoCtx& io_ctx) {
   }
 
   ImageCtx::~ImageCtx() {
+    ldout(cct, 10) << this << " " << __func__ << dendl;
+
     ceph_assert(config_watcher == nullptr);
     ceph_assert(image_watcher == NULL);
     ceph_assert(exclusive_lock == NULL);

src/librbd/Types.h

@@ -115,6 +115,7 @@ struct MigrationInfo {
   std::string pool_namespace;
   std::string image_name;
   std::string image_id;
+  std::string source_spec;
   deep_copy::SnapMap snap_map;
   uint64_t overlap = 0;
   bool flatten = false;
@@ -123,15 +124,16 @@ struct MigrationInfo {
   }
   MigrationInfo(int64_t pool_id, const std::string& pool_namespace,
                 const std::string& image_name, const std::string& image_id,
+                const std::string& source_spec,
                 const deep_copy::SnapMap &snap_map, uint64_t overlap,
                 bool flatten)
     : pool_id(pool_id), pool_namespace(pool_namespace), image_name(image_name),
-      image_id(image_id), snap_map(snap_map), overlap(overlap),
-      flatten(flatten) {
+      image_id(image_id), source_spec(source_spec), snap_map(snap_map),
+      overlap(overlap), flatten(flatten) {
   }
 
   bool empty() const {
-    return pool_id == -1;
+    return (pool_id == -1 && source_spec.empty());
   }
 };