Merge pull request #15875 from xiexingguo/wip-osdmon-20170623

mon/OSDMonitor: "osd crush class rename" support

Reviewed-by: Sage Weil <sage@redhat.com>

src/crush/CrushWrapper.cc

@@ -1537,21 +1537,24 @@ int CrushWrapper::bucket_remove_item(crush_bucket *bucket, int item)
   return crush_bucket_remove_item(crush, bucket, item);
 }
 
-int CrushWrapper::update_device_class(CephContext *cct, int id, const string& class_name, const string& name)
+int CrushWrapper::update_device_class(int id,
+                                      const string& class_name,
+                                      const string& name,
+                                      ostream *ss)
 {
   int class_id = get_class_id(class_name);
   if (class_id < 0) {
-    ldout(cct, 0) << "update_device_class class " << class_name << " does not exist " << dendl;
+    *ss << "class " << class_name << " does not exist";
     return -ENOENT;
   }
   if (id < 0) {
-    ldout(cct, 0) << "update_device_class " << name << " id " << id << " is negative " << dendl;
+    *ss << name << " id " << id << " is negative";
     return -EINVAL;
   }
   assert(item_exists(id));
 
   if (class_map.count(id) != 0 && class_map[id] == class_id) {
-    ldout(cct, 5) << "update_device_class " << name << " already set to class " << class_name << dendl;
+    *ss << name << " already set to class " << class_name;
     return 0;
   }
 

src/crush/CrushWrapper.h

@@ -466,6 +466,22 @@ public:
     class_name.erase(class_id);
     return 0;
   }
+
+  int rename_class(const string& srcname, const string& dstname) {
+    auto p = class_rname.find(srcname);
+    if (p == class_rname.end())
+      return -ENOENT;
+    int class_id = p->second;
+    auto q = class_name.find(class_id);
+    if (q == class_name.end())
+      return -ENOENT;
+    class_rname.erase(srcname);
+    class_name.erase(class_id);
+    class_rname[dstname] = class_id;
+    class_name[class_id] = dstname;
+    return 0;
+  }
+
   int get_or_create_class_id(const string& name) {
     int c = get_class_id(name);
     if (c < 0) {
@@ -1175,7 +1191,7 @@ public:
     have_uniform_rules = !has_legacy_rulesets();
   }
 
-  int update_device_class(CephContext *cct, int id, const string& class_name, const string& name);
+  int update_device_class(int id, const string& class_name, const string& name, ostream *ss);
   int device_class_clone(int original, int device_class, int *clone);
   bool class_is_in_use(int class_id);
   int populate_classes();

src/mon/MonCommands.h

@@ -616,6 +616,11 @@ COMMAND("osd crush class rm " \
 	"name=class,type=CephString,goodchars=[A-Za-z0-9-_]", \
 	"remove crush device class <class>", \
 	"osd", "rw", "cli,rest")
+COMMAND("osd crush class rename " \
+        "name=srcname,type=CephString,goodchars=[A-Za-z0-9-_] " \
+        "name=dstname,type=CephString,goodchars=[A-Za-z0-9-_]", \
+        "rename crush device class <srcname> to <dstname>", \
+        "osd", "rw", "cli,rest")
 COMMAND("osd crush class ls", \
 	"list all crush device classes", \
 	"osd", "r", "cli,rest")

src/mon/OSDMonitor.cc

@@ -7070,8 +7070,7 @@ bool OSDMonitor::prepare_command_impl(MonOpRequestRef op,
 
     dout(5) << action << " crush item id " << osdid << " name '"
 	    << name << "' device_class " << device_class << dendl;
-    err = newcrush.update_device_class(g_ceph_context, osdid, device_class, name);
-
+    err = newcrush.update_device_class(osdid, device_class, name, &ss);
     if (err < 0)
       goto reply;
 
@@ -7216,6 +7215,53 @@ bool OSDMonitor::prepare_command_impl(MonOpRequestRef op,
     ss << "removed class " << device_class << " with id " << class_id
        << " from crush map";
     goto update;
+
+  } else if (prefix == "osd crush class rename") {
+    string srcname, dstname;
+    if (!cmd_getval(g_ceph_context, cmdmap, "srcname", srcname)) {
+      err = -EINVAL;
+      goto reply;
+    }
+
+    if (!cmd_getval(g_ceph_context, cmdmap, "dstname", dstname)) {
+      err = -EINVAL;
+      goto reply;
+    }
+
+    CrushWrapper newcrush;
+    _get_pending_crush(newcrush);
+
+    if (!newcrush.class_exists(srcname)) {
+      err = -ENOENT;
+      ss << "class '" << srcname << "' does not exist";
+      goto reply;
+    }
+
+    if (newcrush.class_exists(dstname)) {
+      err = -EEXIST;
+      ss << "class '" << dstname << "' already exists";
+      goto reply;
+    }
+
+    int class_id = newcrush.get_class_id(srcname);
+
+    if (newcrush.class_is_in_use(class_id)) {
+      err = -EBUSY;
+      ss << "class '" << srcname << "' is in use";
+      goto reply;
+    }
+
+    err = newcrush.rename_class(srcname, dstname);
+    if (err < 0) {
+      ss << "fail to rename '" << srcname << "' to '" << dstname << "':"
+         << cpp_strerror(err);
+      goto reply;
+    }
+
+    pending_inc.crush.clear();
+    newcrush.encode(pending_inc.crush, mon->get_quorum_con_features());
+    ss << "rename class '" << srcname << "' to '" << dstname << "'";
+    goto update;
     
   } else if (osdid_present &&
 	     (prefix == "osd crush set" || prefix == "osd crush add")) {
@@ -7414,6 +7460,7 @@ bool OSDMonitor::prepare_command_impl(MonOpRequestRef op,
     int r = newcrush.swap_bucket(g_ceph_context, sid, did);
     if (r < 0) {
       ss << "failed to swap bucket contents: " << cpp_strerror(r);
+      err = r;
       goto reply;
     }
     ss << "swapped bucket of " << source << " to " << dest;

src/test/crush/crush-classes.sh

@@ -135,6 +135,10 @@ function TEST_mon_classes() {
     ceph osd crush class create CLASS || return 1
     ceph osd crush class create CLASS || return 1 # idempotent
     ceph osd crush class ls | grep CLASS  || return 1
+    ceph osd crush class rename CLASS TEMP || return 1
+    ceph osd crush class ls | grep TEMP || return 1
+    ceph osd crush class rename TEMP CLASS || return 1
+    ceph osd crush class ls | grep CLASS  || return 1
     ceph osd crush class rm CLASS || return 1
     expect_failure $dir ENOENT ceph osd crush class rm CLASS || return 1
 }