From: Igor Fedotov <ifedotov@suse.com>
Date: Tue, 31 Aug 2021 12:54:23 +0000 (+0300)
Subject: os/bluestore: fix bluefs migrate command
X-Git-Tag: v16.2.6~4^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=1f7435094b1a4055def9361e57db1d04d7db6e82;p=ceph.git

os/bluestore: fix bluefs migrate command

After migrating DB volume to a slow one RocksDB still
needs to be provided with slow.db path to properly access relevant files under db.slow subfolder.
Without that specification it tries to access them under 'db' one which
results in "not-found" error.

Fixes: https://tracker.ceph.com/issues/40434
Signed-off-by: Igor Fedotov <ifedotov@suse.com>
(cherry picked from commit 90852d9b6f0da7967121200c9a1c56bed1929d2d)
---

diff --git a/src/os/bluestore/BlueFS.cc b/src/os/bluestore/BlueFS.cc
index 2ddfbbed0f28..16b64636b891 100644
--- a/src/os/bluestore/BlueFS.cc
+++ b/src/os/bluestore/BlueFS.cc
@@ -3837,7 +3837,9 @@ uint8_t OriginalVolumeSelector::select_prefer_bdev(void* hint)
 void OriginalVolumeSelector::get_paths(const std::string& base, paths& res) const
 {
   res.emplace_back(base, db_total);
-  res.emplace_back(base + ".slow", slow_total);
+  res.emplace_back(base + ".slow",
+    slow_total ? slow_total : db_total); // use fake non-zero value if needed to
+                                         // avoid RocksDB complains
 }
 
 #undef dout_prefix
diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index e74343cdfd01..ba52666a011d 100644
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -6021,9 +6021,7 @@ int BlueStore::_prepare_db_environment(bool create, bool read_only,
     BlueFSVolumeSelector::paths paths;
     bluefs->get_vselector_paths(fn, paths);
 
-    if (bluefs_layout.shared_bdev == BlueFS::BDEV_SLOW) {
-      // we have both block.db and block; tell rocksdb!
-      // note: the second (last) size value doesn't really matter
+    {
       ostringstream db_paths;
       bool first = true;
       for (auto& p : paths) {