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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:45:59 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:45:59 +0000
commit19fcec84d8d7d21e796c7624e521b60d28ee21ed (patch)
tree42d26aa27d1e3f7c0b8bd3fd14e7d7082f5008dc /src/key_value_store/cls_kvs.cc
parentInitial commit. (diff)
downloadceph-19fcec84d8d7d21e796c7624e521b60d28ee21ed.tar.xz
ceph-19fcec84d8d7d21e796c7624e521b60d28ee21ed.zip
Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/key_value_store/cls_kvs.cc')
-rw-r--r--src/key_value_store/cls_kvs.cc690
1 files changed, 690 insertions, 0 deletions
diff --git a/src/key_value_store/cls_kvs.cc b/src/key_value_store/cls_kvs.cc
new file mode 100644
index 000000000..d206e3743
--- /dev/null
+++ b/src/key_value_store/cls_kvs.cc
@@ -0,0 +1,690 @@
+/*
+ * OSD classes for the key value store
+ *
+ * Created on: Aug 10, 2012
+ * Author: Eleanor Cawthon
+ */
+
+#include "include/compat.h"
+#include "objclass/objclass.h"
+#include <errno.h>
+#include "key_value_store/kvs_arg_types.h"
+#include "include/types.h"
+#include <iostream>
+#include <climits>
+
+
+/**
+ * finds the index_data where a key belongs.
+ *
+ * @param key: the key to search for
+ * @param idata: the index_data for the first index value such that idata.key
+ * is greater than key.
+ * @param next_idata: the index_data for the next index entry after idata
+ * @pre: key is not encoded
+ * @post: idata contains complete information
+ * stored
+ */
+static int get_idata_from_key(cls_method_context_t hctx, const string &key,
+ index_data &idata, index_data &next_idata) {
+ bufferlist raw_val;
+ int r = 0;
+ std::map<std::string, bufferlist> kvmap;
+
+ bool more;
+
+ r = cls_cxx_map_get_vals(hctx, key_data(key).encoded(), "", 2, &kvmap, &more);
+ if (r < 0) {
+ CLS_LOG(20, "error reading index for range %s: %d", key.c_str(), r);
+ return r;
+ }
+
+ r = cls_cxx_map_get_val(hctx, key_data(key).encoded(), &raw_val);
+ if (r == 0){
+ CLS_LOG(20, "%s is already in the index: %d", key.c_str(), r);
+ auto b = raw_val.cbegin();
+ idata.decode(b);
+ if (!kvmap.empty()) {
+ auto b = kvmap.begin()->second.cbegin();
+ next_idata.decode(b);
+ }
+ return r;
+ } else if (r == -ENOENT || r == -ENODATA) {
+ auto b = kvmap.begin()->second.cbegin();
+ idata.decode(b);
+ if (idata.kdata.prefix != "1") {
+ auto nb = (++kvmap.begin())->second.cbegin();
+ next_idata.decode(nb);
+ }
+ r = 0;
+ } else if (r < 0) {
+ CLS_LOG(20, "error reading index for duplicates %s: %d", key.c_str(), r);
+ return r;
+ }
+
+ CLS_LOG(20, "idata is %s", idata.str().c_str());
+ return r;
+}
+
+
+static int get_idata_from_key_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "get_idata_from_key_op");
+ idata_from_key_args op;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error& err) {
+ CLS_LOG(20, "error decoding idata_from_key_args.");
+ return -EINVAL;
+ }
+ int r = get_idata_from_key(hctx, op.key, op.idata, op.next_idata);
+ if (r < 0) {
+ return r;
+ } else {
+ encode(op, *out);
+ return 0;
+ }
+}
+
+/**
+ * finds the object in the index with the lowest key value that is greater
+ * than idata.key. If idata.key is the max key, returns -EOVERFLOW. If
+ * idata has a prefix and has timed out, cleans up.
+ *
+ * @param idata: idata for the object to search for.
+ * @param out_data: the idata for the next object.
+ *
+ * @pre: idata must contain a key.
+ * @post: out_data contains complete information
+ */
+static int get_next_idata(cls_method_context_t hctx, const index_data &idata,
+ index_data &out_data) {
+ int r = 0;
+ std::map<std::string, bufferlist> kvs;
+ bool more;
+ r = cls_cxx_map_get_vals(hctx, idata.kdata.encoded(), "", 1, &kvs, &more);
+ if (r < 0){
+ CLS_LOG(20, "getting kvs failed with error %d", r);
+ return r;
+ }
+
+ if (!kvs.empty()) {
+ out_data.kdata.parse(kvs.begin()->first);
+ auto b = kvs.begin()->second.cbegin();
+ out_data.decode(b);
+ } else {
+ r = -EOVERFLOW;
+ }
+
+ return r;
+}
+
+static int get_next_idata_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "get_next_idata_op");
+ idata_from_idata_args op;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error& err) {
+ return -EINVAL;
+ }
+ int r = get_next_idata(hctx, op.idata, op.next_idata);
+ if (r < 0) {
+ return r;
+ } else {
+ op.encode(*out);
+ return 0;
+ }
+}
+
+/**
+ * finds the object in the index with the highest key value that is less
+ * than idata.key. If idata.key is the lowest key, returns -ERANGE If
+ * idata has a prefix and has timed out, cleans up.
+ *
+ * @param idata: idata for the object to search for.
+ * @param out_data: the idata for the next object.
+ *
+ * @pre: idata must contain a key.
+ * @ost: out_data contains complete information
+ */
+static int get_prev_idata(cls_method_context_t hctx, const index_data &idata,
+ index_data &out_data) {
+ int r = 0;
+ std::map<std::string, bufferlist> kvs;
+ bool more;
+ r = cls_cxx_map_get_vals(hctx, "", "", LONG_MAX, &kvs, &more);
+ if (r < 0){
+ CLS_LOG(20, "getting kvs failed with error %d", r);
+ return r;
+ }
+
+ std::map<std::string, bufferlist>::iterator it =
+ kvs.lower_bound(idata.kdata.encoded());
+ if (it->first != idata.kdata.encoded()) {
+ CLS_LOG(20, "object %s not found in the index (expected %s, found %s)",
+ idata.str().c_str(), idata.kdata.encoded().c_str(),
+ it->first.c_str());
+ return -ENODATA;
+ }
+ if (it == kvs.begin()) {
+ //it is the first object, there is no previous.
+ return -ERANGE;
+ } else {
+ --it;
+ }
+ out_data.kdata.parse(it->first);
+ auto b = it->second.cbegin();
+ out_data.decode(b);
+
+ return 0;
+}
+
+static int get_prev_idata_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "get_next_idata_op");
+ idata_from_idata_args op;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error& err) {
+ return -EINVAL;
+ }
+ int r = get_prev_idata(hctx, op.idata, op.next_idata);
+ if (r < 0) {
+ return r;
+ } else {
+ op.encode(*out);
+ return 0;
+ }
+}
+
+/**
+ * Read all of the index entries where any keys in the map go
+ */
+static int read_many(cls_method_context_t hctx, const set<string> &keys,
+ map<string, bufferlist> * out) {
+ int r = 0;
+ bool more;
+ CLS_ERR("reading from a map of size %d, first key encoded is %s",
+ (int)keys.size(), key_data(*keys.begin()).encoded().c_str());
+ r = cls_cxx_map_get_vals(hctx, key_data(*keys.begin()).encoded().c_str(),
+ "", LONG_MAX, out, &more);
+ if (r < 0) {
+ CLS_ERR("getting omap vals failed with error %d", r);
+ }
+
+ CLS_ERR("got map of size %d ", (int)out->size());
+ if (out->size() > 1) {
+ out->erase(out->upper_bound(key_data(*keys.rbegin()).encoded().c_str()),
+ out->end());
+ }
+ CLS_ERR("returning map of size %d", (int)out->size());
+ return r;
+}
+
+static int read_many_op(cls_method_context_t hctx, bufferlist *in,
+ bufferlist *out) {
+ CLS_LOG(20, "read_many_op");
+ set<string> op;
+ map<string, bufferlist> outmap;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error & err) {
+ return -EINVAL;
+ }
+ int r = read_many(hctx, op, &outmap);
+ if (r < 0) {
+ return r;
+ } else {
+ encode(outmap, *out);
+ return 0;
+ }
+}
+
+/**
+ * Checks the unwritable xattr. If it is "1" (i.e., it is unwritable), returns
+ * -EACCES. otherwise, returns 0.
+ */
+static int check_writable(cls_method_context_t hctx) {
+ bufferlist bl;
+ int r = cls_cxx_getxattr(hctx, "unwritable", &bl);
+ if (r < 0) {
+ CLS_LOG(20, "error reading xattr %s: %d", "unwritable", r);
+ return r;
+ }
+ if (string(bl.c_str(), bl.length()) == "1") {
+ return -EACCES;
+ } else{
+ return 0;
+ }
+}
+
+static int check_writable_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "check_writable_op");
+ return check_writable(hctx);
+}
+
+/**
+ * returns -EKEYREJECTED if size is outside of bound, according to comparator.
+ *
+ * @bound: the limit to test
+ * @comparator: should be CEPH_OSD_CMPXATTR_OP_[EQ|GT|LT]
+ */
+static int assert_size_in_bound(cls_method_context_t hctx, int bound,
+ int comparator) {
+ //determine size
+ bufferlist size_bl;
+ int r = cls_cxx_getxattr(hctx, "size", &size_bl);
+ if (r < 0) {
+ CLS_LOG(20, "error reading xattr %s: %d", "size", r);
+ return r;
+ }
+
+ int size = atoi(string(size_bl.c_str(), size_bl.length()).c_str());
+ CLS_LOG(20, "size is %d, bound is %d", size, bound);
+
+ //compare size to comparator
+ switch (comparator) {
+ case CEPH_OSD_CMPXATTR_OP_EQ:
+ if (size != bound) {
+ return -EKEYREJECTED;
+ }
+ break;
+ case CEPH_OSD_CMPXATTR_OP_LT:
+ if (size >= bound) {
+ return -EKEYREJECTED;
+ }
+ break;
+ case CEPH_OSD_CMPXATTR_OP_GT:
+ if (size <= bound) {
+ return -EKEYREJECTED;
+ }
+ break;
+ default:
+ CLS_LOG(20, "invalid argument passed to assert_size_in_bound: %d",
+ comparator);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int assert_size_in_bound_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "assert_size_in_bound_op");
+ assert_size_args op;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error& err) {
+ return -EINVAL;
+ }
+ return assert_size_in_bound(hctx, op.bound, op.comparator);
+}
+
+/**
+ * Attempts to insert omap into this object's omap.
+ *
+ * @return:
+ * if unwritable, returns -EACCES.
+ * if size > bound and key doesn't already exist in the omap, returns -EBALANCE.
+ * if exclusive is true, returns -EEXIST if any keys already exist.
+ *
+ * @post: object has omap entries inserted, and size xattr is updated
+ */
+static int omap_insert(cls_method_context_t hctx,
+ const map<string, bufferlist> &omap, int bound, bool exclusive) {
+
+ uint64_t size;
+ time_t time;
+ int r = cls_cxx_stat(hctx, &size, &time);
+ if (r < 0) {
+ return r;
+ }
+ CLS_LOG(20, "inserting %s", omap.begin()->first.c_str());
+ r = check_writable(hctx);
+ if (r < 0) {
+ CLS_LOG(20, "omap_insert: this object is unwritable: %d", r);
+ return r;
+ }
+
+ int assert_bound = bound;
+
+ //if this is an exclusive insert, make sure the key doesn't already exist.
+ for (map<string, bufferlist>::const_iterator it = omap.begin();
+ it != omap.end(); ++it) {
+ bufferlist bl;
+ r = cls_cxx_map_get_val(hctx, it->first, &bl);
+ if (r == 0 && string(bl.c_str(), bl.length()) != ""){
+ if (exclusive) {
+ CLS_LOG(20, "error: this is an exclusive insert and %s exists.",
+ it->first.c_str());
+ return -EEXIST;
+ }
+ assert_bound++;
+ CLS_LOG(20, "increased assert_bound to %d", assert_bound);
+ } else if (r != -ENODATA && r != -ENOENT) {
+ CLS_LOG(20, "error reading omap val for %s: %d", it->first.c_str(), r);
+ return r;
+ }
+ }
+
+ bufferlist old_size;
+ r = cls_cxx_getxattr(hctx, "size", &old_size);
+ if (r < 0) {
+ CLS_LOG(20, "error reading xattr %s: %d", "size", r);
+ return r;
+ }
+
+ int old_size_int = atoi(string(old_size.c_str(), old_size.length()).c_str());
+
+ CLS_LOG(20, "asserting size is less than %d (bound is %d)", assert_bound, bound);
+ if (old_size_int >= assert_bound) {
+ return -EKEYREJECTED;
+ }
+
+ int new_size_int = old_size_int + omap.size() - (assert_bound - bound);
+ CLS_LOG(20, "old size is %d, new size is %d", old_size_int, new_size_int);
+ bufferlist new_size;
+ stringstream s;
+ s << new_size_int;
+ new_size.append(s.str());
+
+ r = cls_cxx_map_set_vals(hctx, &omap);
+ if (r < 0) {
+ CLS_LOG(20, "error setting omap: %d", r);
+ return r;
+ }
+
+ r = cls_cxx_setxattr(hctx, "size", &new_size);
+ if (r < 0) {
+ CLS_LOG(20, "error setting xattr %s: %d", "size", r);
+ return r;
+ }
+ CLS_LOG(20, "successfully inserted %s", omap.begin()->first.c_str());
+ return 0;
+}
+
+static int omap_insert_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "omap_insert");
+ omap_set_args op;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error& err) {
+ return -EINVAL;
+ }
+ return omap_insert(hctx, op.omap, op.bound, op.exclusive);
+}
+
+static int create_with_omap(cls_method_context_t hctx,
+ const map<string, bufferlist> &omap) {
+ CLS_LOG(20, "creating with omap: %s", omap.begin()->first.c_str());
+ //first make sure the object is writable
+ int r = cls_cxx_create(hctx, true);
+ if (r < 0) {
+ CLS_LOG(20, "omap create: creating failed: %d", r);
+ return r;
+ }
+
+ int new_size_int = omap.size();
+ CLS_LOG(20, "omap insert: new size is %d", new_size_int);
+ bufferlist new_size;
+ stringstream s;
+ s << new_size_int;
+ new_size.append(s.str());
+
+ r = cls_cxx_map_set_vals(hctx, &omap);
+ if (r < 0) {
+ CLS_LOG(20, "omap create: error setting omap: %d", r);
+ return r;
+ }
+
+ r = cls_cxx_setxattr(hctx, "size", &new_size);
+ if (r < 0) {
+ CLS_LOG(20, "omap create: error setting xattr %s: %d", "size", r);
+ return r;
+ }
+
+ bufferlist u;
+ u.append("0");
+ r = cls_cxx_setxattr(hctx, "unwritable", &u);
+ if (r < 0) {
+ CLS_LOG(20, "omap create: error setting xattr %s: %d", "unwritable", r);
+ return r;
+ }
+
+ CLS_LOG(20, "successfully created %s", omap.begin()->first.c_str());
+ return 0;
+}
+
+static int create_with_omap_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "omap_insert");
+ map<string, bufferlist> omap;
+ auto it = in->cbegin();
+ try {
+ decode(omap, it);
+ } catch (buffer::error& err) {
+ return -EINVAL;
+ }
+ return create_with_omap(hctx, omap);
+}
+
+/**
+ * Attempts to remove omap from this object's omap.
+ *
+ * @return:
+ * if unwritable, returns -EACCES.
+ * if size < bound and key doesn't already exist in the omap, returns -EBALANCE.
+ * if any of the keys are not in this object, returns -ENODATA.
+ *
+ * @post: object has omap entries removed, and size xattr is updated
+ */
+static int omap_remove(cls_method_context_t hctx,
+ const std::set<string> &omap, int bound) {
+ int r;
+ uint64_t size;
+ time_t time;
+ r = cls_cxx_stat(hctx, &size, &time);
+ if (r < 0) {
+ return r;
+ }
+
+ //first make sure the object is writable
+ r = check_writable(hctx);
+ if (r < 0) {
+ return r;
+ }
+
+ //check for existance of the key first
+ for (set<string>::const_iterator it = omap.begin();
+ it != omap.end(); ++it) {
+ bufferlist bl;
+ r = cls_cxx_map_get_val(hctx, *it, &bl);
+ if (r == -ENOENT || r == -ENODATA
+ || string(bl.c_str(), bl.length()) == ""){
+ return -ENODATA;
+ } else if (r < 0) {
+ CLS_LOG(20, "error reading omap val for %s: %d", it->c_str(), r);
+ return r;
+ }
+ }
+
+ //fail if removing from an object with only bound entries.
+ bufferlist old_size;
+ r = cls_cxx_getxattr(hctx, "size", &old_size);
+ if (r < 0) {
+ CLS_LOG(20, "error reading xattr %s: %d", "size", r);
+ return r;
+ }
+ int old_size_int = atoi(string(old_size.c_str(), old_size.length()).c_str());
+
+ CLS_LOG(20, "asserting size is greater than %d", bound);
+ if (old_size_int <= bound) {
+ return -EKEYREJECTED;
+ }
+
+ int new_size_int = old_size_int - omap.size();
+ CLS_LOG(20, "old size is %d, new size is %d", old_size_int, new_size_int);
+ bufferlist new_size;
+ stringstream s;
+ s << new_size_int;
+ new_size.append(s.str());
+
+ r = cls_cxx_setxattr(hctx, "size", &new_size);
+ if (r < 0) {
+ CLS_LOG(20, "error setting xattr %s: %d", "unwritable", r);
+ return r;
+ }
+
+ for (std::set<string>::const_iterator it = omap.begin();
+ it != omap.end(); ++it) {
+ r = cls_cxx_map_remove_key(hctx, *it);
+ if (r < 0) {
+ CLS_LOG(20, "error removing omap: %d", r);
+ return r;
+ }
+ }
+ return 0;
+}
+
+static int omap_remove_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "omap_remove");
+ omap_rm_args op;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error& err) {
+ return -EINVAL;
+ }
+ return omap_remove(hctx, op.omap, op.bound);
+}
+
+/**
+ * checks to see if this object needs to be split or rebalanced. if so, reads
+ * information about it.
+ *
+ * @post: if assert_size_in_bound(hctx, bound, comparator) succeeds,
+ * odata contains the size, omap, and unwritable attributes for this object.
+ * Otherwise, odata contains the size and unwritable attribute.
+ */
+static int maybe_read_for_balance(cls_method_context_t hctx,
+ object_data &odata, int bound, int comparator) {
+ CLS_LOG(20, "rebalance reading");
+ //if unwritable, return
+ int r = check_writable(hctx);
+ if (r < 0) {
+ odata.unwritable = true;
+ CLS_LOG(20, "rebalance read: error getting xattr %s: %d", "unwritable", r);
+ return r;
+ } else {
+ odata.unwritable = false;
+ }
+
+ //get the size attribute
+ bufferlist size;
+ r = cls_cxx_getxattr(hctx, "size", &size);
+ if (r < 0) {
+ CLS_LOG(20, "rebalance read: error getting xattr %s: %d", "size", r);
+ return r;
+ }
+ odata.size = atoi(string(size.c_str(), size.length()).c_str());
+
+ //check if it needs to be balanced
+ r = assert_size_in_bound(hctx, bound, comparator);
+ if (r < 0) {
+ CLS_LOG(20, "rebalance read: error on asserting size: %d", r);
+ return -EBALANCE;
+ }
+
+ //if the assert succeeded, it needs to be balanced
+ bool more;
+ r = cls_cxx_map_get_vals(hctx, "", "", LONG_MAX, &odata.omap, &more);
+ if (r < 0){
+ CLS_LOG(20, "rebalance read: getting kvs failed with error %d", r);
+ return r;
+ }
+
+ CLS_LOG(20, "rebalance read: size xattr is %llu, omap size is %llu",
+ (unsigned long long)odata.size,
+ (unsigned long long)odata.omap.size());
+ return 0;
+}
+
+static int maybe_read_for_balance_op(cls_method_context_t hctx,
+ bufferlist *in, bufferlist *out) {
+ CLS_LOG(20, "maybe_read_for_balance");
+ rebalance_args op;
+ auto it = in->cbegin();
+ try {
+ decode(op, it);
+ } catch (buffer::error& err) {
+ return -EINVAL;
+ }
+ int r = maybe_read_for_balance(hctx, op.odata, op.bound, op.comparator);
+ if (r < 0) {
+ return r;
+ } else {
+ op.encode(*out);
+ return 0;
+ }
+}
+
+
+CLS_INIT(kvs)
+{
+ CLS_LOG(20, "Loaded assert condition class!");
+
+ cls_handle_t h_class;
+ cls_method_handle_t h_get_idata_from_key;
+ cls_method_handle_t h_get_next_idata;
+ cls_method_handle_t h_get_prev_idata;
+ cls_method_handle_t h_read_many;
+ cls_method_handle_t h_check_writable;
+ cls_method_handle_t h_assert_size_in_bound;
+ cls_method_handle_t h_omap_insert;
+ cls_method_handle_t h_create_with_omap;
+ cls_method_handle_t h_omap_remove;
+ cls_method_handle_t h_maybe_read_for_balance;
+
+ cls_register("kvs", &h_class);
+ cls_register_cxx_method(h_class, "get_idata_from_key",
+ CLS_METHOD_RD,
+ get_idata_from_key_op, &h_get_idata_from_key);
+ cls_register_cxx_method(h_class, "get_next_idata",
+ CLS_METHOD_RD,
+ get_next_idata_op, &h_get_next_idata);
+ cls_register_cxx_method(h_class, "get_prev_idata",
+ CLS_METHOD_RD,
+ get_prev_idata_op, &h_get_prev_idata);
+ cls_register_cxx_method(h_class, "read_many",
+ CLS_METHOD_RD,
+ read_many_op, &h_read_many);
+ cls_register_cxx_method(h_class, "check_writable",
+ CLS_METHOD_RD | CLS_METHOD_WR,
+ check_writable_op, &h_check_writable);
+ cls_register_cxx_method(h_class, "assert_size_in_bound",
+ CLS_METHOD_WR,
+ assert_size_in_bound_op, &h_assert_size_in_bound);
+ cls_register_cxx_method(h_class, "omap_insert",
+ CLS_METHOD_WR,
+ omap_insert_op, &h_omap_insert);
+ cls_register_cxx_method(h_class, "create_with_omap",
+ CLS_METHOD_WR,
+ create_with_omap_op, &h_create_with_omap);
+ cls_register_cxx_method(h_class, "omap_remove",
+ CLS_METHOD_WR,
+ omap_remove_op, &h_omap_remove);
+ cls_register_cxx_method(h_class, "maybe_read_for_balance",
+ CLS_METHOD_RD,
+ maybe_read_for_balance_op, &h_maybe_read_for_balance);
+
+ return;
+}