From: Radoslaw Zarzynski <rzarzyns@redhat.com>
Date: Thu, 17 Nov 2022 21:29:20 +0000 (+0000)
Subject: common, osd: switch SnapMapper::_lookup_purged_snap to use OSDriver
X-Git-Tag: v18.1.0~260^2~39
X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=6f7ed374967706fe9bfe7e2bd385c78f77694739;p=ceph.git

common, osd: switch SnapMapper::_lookup_purged_snap to use OSDriver

Signed-off-by: Radoslaw Zarzynski <rzarzyns@redhat.com>
---

diff --git a/src/common/map_cacher.hpp b/src/common/map_cacher.hpp
index 4698eb78bba85..a83f924b622c0 100644
--- a/src/common/map_cacher.hpp
+++ b/src/common/map_cacher.hpp
@@ -60,6 +60,11 @@ public:
     std::pair<K, V> *next    ///< [out] first key after key
     ) = 0; ///< @return 0 on success, -ENOENT if there is no next
 
+  virtual int get_next_or_current(
+    const K &key,       ///< [in] key at-which-or-after to get
+    std::pair<K, V> *next_or_current
+    ) = 0; ///< @return 0 on success, -ENOENT if there is no next
+
   virtual ~StoreDriver() {}
 };
 
diff --git a/src/osd/SnapMapper.cc b/src/osd/SnapMapper.cc
index 8665eaa4429ef..87a84da8e151d 100644
--- a/src/osd/SnapMapper.cc
+++ b/src/osd/SnapMapper.cc
@@ -87,7 +87,7 @@ int OSDriver::get_keys(
 
 int OSDriver::get_next(
   const std::string &key,
-  pair<std::string, ceph::buffer::list> *next)
+  std::pair<std::string, ceph::buffer::list> *next)
 {
   ObjectMap::ObjectMapIterator iter =
     os->get_omap_iterator(ch, hoid);
@@ -105,6 +105,26 @@ int OSDriver::get_next(
   }
 }
 
+int OSDriver::get_next_or_current(
+  const std::string &key,
+  std::pair<std::string, ceph::buffer::list> *next_or_current)
+{
+  ObjectMap::ObjectMapIterator iter =
+    os->get_omap_iterator(ch, hoid);
+  if (!iter) {
+    ceph_abort();
+    return -EINVAL;
+  }
+  iter->lower_bound(key);
+  if (iter->valid()) {
+    if (next_or_current)
+      *next_or_current = make_pair(iter->key(), iter->value());
+    return 0;
+  } else {
+    return -ENOENT;
+  }
+}
+
 string SnapMapper::get_prefix(int64_t pool, snapid_t snap)
 {
   static_assert(sizeof(pool) == 8, "assumed by the formatting code");
@@ -571,21 +591,21 @@ int SnapMapper::_lookup_purged_snap(
   int64_t pool, snapid_t snap,
   snapid_t *begin, snapid_t *end)
 {
+  OSDriver backend(store, ch, hoid);
   string k = make_purged_snap_key(pool, snap);
-  auto it = store->get_omap_iterator(ch, hoid);
-  it->lower_bound(k);
-  if (!it->valid()) {
+  std::pair<std::string, ceph::buffer::list> kv;
+  if (auto ret = backend.get_next_or_current(k, &kv); ret == -ENOENT) {
     dout(20) << __func__ << " pool " << pool << " snap " << snap
 	     << " key '" << k << "' lower_bound not found" << dendl;
     return -ENOENT;
   }
-  if (it->key().find(PURGED_SNAP_PREFIX) != 0) {
+  if (kv.first.find(PURGED_SNAP_PREFIX) != 0) {
     dout(20) << __func__ << " pool " << pool << " snap " << snap
 	     << " key '" << k << "' lower_bound got mismatched prefix '"
-	     << it->key() << "'" << dendl;
+	     << kv.first << "'" << dendl;
     return -ENOENT;
   }
-  ceph::buffer::list v = it->value();
+  ceph::buffer::list v = kv.second;
   auto p = v.cbegin();
   int64_t gotpool;
   decode(gotpool, p);
diff --git a/src/osd/SnapMapper.h b/src/osd/SnapMapper.h
index 62bdd083cc015..2b3227ba802aa 100644
--- a/src/osd/SnapMapper.h
+++ b/src/osd/SnapMapper.h
@@ -66,16 +66,21 @@ public:
   }
 
   OSDriver(ObjectStore *os, const coll_t& cid, const ghobject_t &hoid) :
+    OSDriver(os, os->open_collection(cid), hoid) {}
+  OSDriver(ObjectStore *os, ObjectStore::CollectionHandle ch, const ghobject_t &hoid) :
     os(os),
-    hoid(hoid) {
-    ch = os->open_collection(cid);
-  }
+    ch(ch),
+    hoid(hoid) {}
+
   int get_keys(
     const std::set<std::string> &keys,
     std::map<std::string, ceph::buffer::list> *out) override;
   int get_next(
     const std::string &key,
     std::pair<std::string, ceph::buffer::list> *next) override;
+  int get_next_or_current(
+    const std::string &key,
+    std::pair<std::string, ceph::buffer::list> *next_or_current) override;
 };
 
 /**
diff --git a/src/test/test_snap_mapper.cc b/src/test/test_snap_mapper.cc
index 3da2ffd42266b..e502892cc42f1 100644
--- a/src/test/test_snap_mapper.cc
+++ b/src/test/test_snap_mapper.cc
@@ -193,6 +193,19 @@ public:
       return -ENOENT;
     }
   }
+  int get_next_or_current(
+    const string &key,
+    pair<string, bufferlist> *next_or_current) override {
+    std::lock_guard l{lock};
+    map<string, bufferlist>::iterator j = store.lower_bound(key);
+    if (j != store.end()) {
+      if (next_or_current)
+	*next_or_current = *j;
+      return 0;
+    } else {
+      return -ENOENT;
+    }
+  }
   void submit(Transaction *t) {
     doer.submit(t->ops);
     doer.submit(t->callbacks);