1 files changed, 217 insertions, 0 deletions
diff --git a/src/cls/refcount/cls_refcount.cc b/src/cls/refcount/cls_refcount.cc
new file mode 100644
index 000000000..781d967f9
--- /dev/null
+++ b/src/cls/refcount/cls_refcount.cc
@@ -0,0 +1,217 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include <errno.h>
+
+#include "objclass/objclass.h"
+#include "cls/refcount/cls_refcount_ops.h"
+
+#include "include/compat.h"
+
+using std::string;
+
+using ceph::bufferlist;
+
+CLS_VER(1,0)
+CLS_NAME(refcount)
+
+#define REFCOUNT_ATTR "refcount"
+
+static string wildcard_tag;
+
+static int read_refcount(cls_method_context_t hctx, bool implicit_ref, obj_refcount *objr)
+{
+  bufferlist bl;
+  objr->refs.clear();
+  int ret = cls_cxx_getxattr(hctx, REFCOUNT_ATTR, &bl);
+  if (ret == -ENODATA) {
+    if (implicit_ref) {
+      objr->refs[wildcard_tag] = true;
+    }
+    return 0;
+  }
+  if (ret < 0)
+    return ret;
+
+  try {
+    auto iter = bl.cbegin();
+    decode(*objr, iter);
+  } catch (ceph::buffer::error& err) {
+    CLS_LOG(0, "ERROR: read_refcount(): failed to decode refcount entry\n");
+    return -EIO;
+  }
+
+  return 0;
+}
+
+static int set_refcount(cls_method_context_t hctx, const struct obj_refcount& objr)
+{
+  bufferlist bl;
+
+  encode(objr, bl);
+
+  int ret = cls_cxx_setxattr(hctx, REFCOUNT_ATTR, &bl);
+  if (ret < 0)
+    return ret;
+
+  return 0;
+}
+
+static int cls_rc_refcount_get(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+  auto in_iter = in->cbegin();
+
+  cls_refcount_get_op op;
+  try {
+    decode(op, in_iter);
+  } catch (ceph::buffer::error& err) {
+    CLS_LOG(1, "ERROR: cls_rc_refcount_get(): failed to decode entry\n");
+    return -EINVAL;
+  }
+
+  obj_refcount objr;
+  int ret = read_refcount(hctx, op.implicit_ref, &objr);
+  if (ret < 0)
+    return ret;
+
+  CLS_LOG(10, "cls_rc_refcount_get() tag=%s\n", op.tag.c_str());
+
+  objr.refs[op.tag] = true;
+
+  ret = set_refcount(hctx, objr);
+  if (ret < 0)
+    return ret;
+
+  return 0;
+}
+
+static int cls_rc_refcount_put(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+  auto in_iter = in->cbegin();
+
+  cls_refcount_put_op op;
+  try {
+    decode(op, in_iter);
+  } catch (ceph::buffer::error& err) {
+    CLS_LOG(1, "ERROR: cls_rc_refcount_put(): failed to decode entry\n");
+    return -EINVAL;
+  }
+
+  obj_refcount objr;
+  int ret = read_refcount(hctx, op.implicit_ref, &objr);
+  if (ret < 0)
+    return ret;
+
+  if (objr.refs.empty()) {// shouldn't happen!
+    CLS_LOG(0, "ERROR: cls_rc_refcount_put() was called without any references!\n");
+    return -EINVAL;
+  }
+
+  CLS_LOG(10, "cls_rc_refcount_put() tag=%s\n", op.tag.c_str());
+
+  bool found = false;
+  auto iter = objr.refs.find(op.tag);
+  if (iter != objr.refs.end()) {
+    found = true;
+  } else if (op.implicit_ref) {
+    iter = objr.refs.find(wildcard_tag);
+    if (iter != objr.refs.end()) {
+      found = true;
+    }
+  }
+
+  if (!found ||
+      objr.retired_refs.find(op.tag) != objr.retired_refs.end())
+    return 0;
+
+  objr.retired_refs.insert(op.tag);
+  objr.refs.erase(iter);
+
+  if (objr.refs.empty()) {
+    return cls_cxx_remove(hctx);
+  }
+
+  ret = set_refcount(hctx, objr);
+  if (ret < 0)
+    return ret;
+
+  return 0;
+}
+
+static int cls_rc_refcount_set(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+  auto in_iter = in->cbegin();
+
+  cls_refcount_set_op op;
+  try {
+    decode(op, in_iter);
+  } catch (ceph::buffer::error& err) {
+    CLS_LOG(1, "ERROR: cls_refcount_set(): failed to decode entry\n");
+    return -EINVAL;
+  }
+
+  if (!op.refs.size()) {
+    return cls_cxx_remove(hctx);
+  }
+
+  obj_refcount objr;
+  for (auto iter = op.refs.begin(); iter != op.refs.end(); ++iter) {
+    objr.refs[*iter] = true;
+  }
+
+  int ret = set_refcount(hctx, objr);
+  if (ret < 0)
+    return ret;
+
+  return 0;
+}
+
+static int cls_rc_refcount_read(cls_method_context_t hctx, bufferlist *in, bufferlist *out)
+{
+  auto in_iter = in->cbegin();
+
+  cls_refcount_read_op op;
+  try {
+    decode(op, in_iter);
+  } catch (ceph::buffer::error& err) {
+    CLS_LOG(1, "ERROR: cls_rc_refcount_read(): failed to decode entry\n");
+    return -EINVAL;
+  }
+
+  obj_refcount objr;
+
+  cls_refcount_read_ret read_ret;
+  int ret = read_refcount(hctx, op.implicit_ref, &objr);
+  if (ret < 0)
+    return ret;
+
+  for (auto iter = objr.refs.begin(); iter != objr.refs.end(); ++iter) {
+    read_ret.refs.push_back(iter->first);
+  }
+
+  encode(read_ret, *out);
+
+  return 0;
+}
+
+CLS_INIT(refcount)
+{
+  CLS_LOG(1, "Loaded refcount class!");
+
+  cls_handle_t h_class;
+  cls_method_handle_t h_refcount_get;
+  cls_method_handle_t h_refcount_put;
+  cls_method_handle_t h_refcount_set;
+  cls_method_handle_t h_refcount_read;
+
+  cls_register("refcount", &h_class);
+
+  /* refcount */
+  cls_register_cxx_method(h_class, "get", CLS_METHOD_RD | CLS_METHOD_WR, cls_rc_refcount_get, &h_refcount_get);
+  cls_register_cxx_method(h_class, "put", CLS_METHOD_RD | CLS_METHOD_WR, cls_rc_refcount_put, &h_refcount_put);
+  cls_register_cxx_method(h_class, "set", CLS_METHOD_RD | CLS_METHOD_WR, cls_rc_refcount_set, &h_refcount_set);
+  cls_register_cxx_method(h_class, "read", CLS_METHOD_RD, cls_rc_refcount_read, &h_refcount_read);
+
+  return;
+}
+