rbd: allow to migrate parent if force flag set

Signed-off-by: Mykola Golub <mgolub@suse.com>

diff --git a/src/test/cli/rbd/help.t b/src/test/cli/rbd/help.t
index 1f642694d01f61938aecf389e47346d881cb72ca..6cbc9ccd19455594028e4e7a5893bcf1f44cd53d 100644 (file)
--- a/src/test/cli/rbd/help.t
+++ b/src/test/cli/rbd/help.t
@@ -1414,7 +1414,7 @@
   
   rbd help migration commit
   usage: rbd migration commit [--pool <pool>] [--namespace <namespace>] 
-                              [--image <image>] [--no-progress] 
+                              [--image <image>] [--no-progress] [--force] 
                               <image-spec> 
   
   Commit image migration.
@@ -1428,6 +1428,7 @@
     --namespace arg      namespace name
     --image arg          image name
     --no-progress        disable progress output
+    --force              proceed even if the image has children
   
   rbd help migration execute
   usage: rbd migration execute [--pool <pool>] [--namespace <namespace>] 

diff --git a/src/tools/rbd/Utils.cc b/src/tools/rbd/Utils.cc
index 90725387908c387b6519a998e5a1517c0db28604..d4f500226ed27ea17f91ed62443cae8e577f446a 100644 (file)
--- a/src/tools/rbd/Utils.cc
+++ b/src/tools/rbd/Utils.cc
@@ -690,10 +690,14 @@ int init_io_ctx(librados::Rados &rados, const std::string &pool_name,
     return r;
   }
 
+  return set_namespace(namespace_name, io_ctx);
+}
+
+int set_namespace(const std::string& namespace_name, librados::IoCtx *io_ctx) {
   if (!namespace_name.empty()) {
     librbd::RBD rbd;
     bool exists = false;
-    r = rbd.namespace_exists(*io_ctx, namespace_name.c_str(), &exists);
+    int r = rbd.namespace_exists(*io_ctx, namespace_name.c_str(), &exists);
     if (r < 0) {
       std::cerr << "rbd: error asserting namespace: "
                 << cpp_strerror(r) << std::endl;

diff --git a/src/tools/rbd/Utils.h b/src/tools/rbd/Utils.h
index e848051d9e04418581a087db9452ffd2ae9ccd29..81ea2c714302cb6fbba224949f7334cb6fee33c0 100644 (file)
--- a/src/tools/rbd/Utils.h
+++ b/src/tools/rbd/Utils.h
@@ -157,6 +157,7 @@ int init(const std::string &pool_name, const std::string& namespace_name,
          librados::Rados *rados, librados::IoCtx *io_ctx);
 int init_io_ctx(librados::Rados &rados, const std::string &pool_name,
                 const std::string& namespace_name, librados::IoCtx *io_ctx);
+int set_namespace(const std::string& namespace_name, librados::IoCtx *io_ctx);
 
 void disable_cache();
 

diff --git a/src/tools/rbd/action/Migration.cc b/src/tools/rbd/action/Migration.cc
index fe05b14bef3105d3e60f665db2dea19d7cb26b0c..bb05e376d01e82a16e367b7a677f4d95b5f79742 100644 (file)
--- a/src/tools/rbd/action/Migration.cc
+++ b/src/tools/rbd/action/Migration.cc
@@ -62,10 +62,75 @@ static int do_abort(librados::IoCtx& io_ctx, const std::string &image_name,
 }
 
 static int do_commit(librados::IoCtx& io_ctx, const std::string &image_name,
-                     bool no_progress) {
+                     bool force, bool no_progress) {
+  librbd::image_migration_status_t migration_status;
+  int r = librbd::RBD().migration_status(io_ctx, image_name.c_str(),
+                                         &migration_status,
+                                         sizeof(migration_status));
+  if (r < 0) {
+    std::cerr << "rbd: getting migration status failed: " << cpp_strerror(r)
+              << std::endl;
+    return r;
+  }
+
+  librados::IoCtx dst_io_ctx;
+  r = librados::Rados(io_ctx).ioctx_create2(migration_status.dest_pool_id, dst_io_ctx);
+  if (r < 0) {
+    std::cerr << "rbd: accessing source pool id="
+              << migration_status.dest_pool_id << " failed: "
+              << cpp_strerror(r) << std::endl;
+    return r;
+  }
+
+  r = utils::set_namespace(migration_status.dest_pool_namespace, &dst_io_ctx);
+  if (r < 0) {
+    return r;
+  }
+
+  librbd::Image image;
+  r = utils::open_image_by_id(dst_io_ctx, migration_status.dest_image_id,
+                              true, &image);
+  if (r < 0) {
+    return r;
+  }
+
+  std::vector<librbd::linked_image_spec_t> children;
+  r = image.list_descendants(&children);
+  if (r < 0) {
+    std::cerr << "rbd: listing descendants failed: " << cpp_strerror(r)
+              << std::endl;
+    return r;
+  }
+
+  if (children.size() > 0) {
+    std::cerr << "rbd: the image has "
+              << (children.size() == 1 ? "a descendant" : "descendants") << ": "
+              << std::endl;
+    for (auto& child : children) {
+      std::cerr << "  " << child.pool_name << "/";
+      if (!child.pool_namespace.empty()) {
+        std::cerr << child.pool_namespace << "/";
+      }
+      std::cerr << child.image_name;
+      if (child.trash) {
+        std::cerr << " (trash " << child.image_id << ")";
+      }
+      std::cerr << std::endl;
+    }
+    std::cerr << "Warning: in-use, read-only descendant images"
+              << " will not detect the parent update." << std::endl;
+    if (force) {
+      std::cerr << "Proceeding anyway due to force flag set." << std::endl;
+    } else {
+      std::cerr << "Ensure no descendant images are opened read-only"
+                << " and run again with force flag." << std::endl;
+      return -EBUSY;
+    }
+  }
+
   utils::ProgressContext pc("Commit image migration", no_progress);
-  int r = librbd::RBD().migration_commit_with_progress(io_ctx,
-                                                       image_name.c_str(), pc);
+  r = librbd::RBD().migration_commit_with_progress(io_ctx, image_name.c_str(),
+                                                   pc);
   if (r < 0) {
     pc.fail();
     std::cerr << "rbd: committing migration failed: " << cpp_strerror(r)
@@ -217,6 +282,8 @@ void get_commit_arguments(po::options_description *positional,
                           po::options_description *options) {
   at::add_image_spec_options(positional, options, at::ARGUMENT_MODIFIER_NONE);
   at::add_no_progress_option(options);
+  options->add_options()
+      ("force", po::bool_switch(), "proceed even if the image has children");
 }
 
 int execute_commit(const po::variables_map &vm,
@@ -241,7 +308,8 @@ int execute_commit(const po::variables_map &vm,
   }
   io_ctx.set_osdmap_full_try();
 
-  r = do_commit(io_ctx, image_name, vm[at::NO_PROGRESS].as<bool>());
+  r = do_commit(io_ctx, image_name, vm["force"].as<bool>(),
+                vm[at::NO_PROGRESS].as<bool>());
   if (r < 0) {
     return r;
   }