From 99fe9eb7b727e3873dd7af8e08cbc76e695418e6 Mon Sep 17 00:00:00 2001
From: Casey Bodley <cbodley@redhat.com>
Date: Thu, 19 Aug 2021 17:21:37 -0400
Subject: [PATCH] radosgw-admin: bucket sync status handles missing full status

if the full sync status object is missing, it's possible that we just
haven't started syncing it again after upgrading from just the per-shard
status objects

in this case, as long as we have a log generation 0, assume that we just
haven't initialized the full status object and try to read the gen=0
per-shard incremental status for comparison

Signed-off-by: Casey Bodley <cbodley@redhat.com>
---
 src/rgw/rgw_admin.cc | 56 +++++++++++++++++++++++++++++---------------
 1 file changed, 37 insertions(+), 19 deletions(-)

diff --git a/src/rgw/rgw_admin.cc b/src/rgw/rgw_admin.cc
index b4067f5af90c6..6d59cd3d783e8 100644
--- a/src/rgw/rgw_admin.cc
+++ b/src/rgw/rgw_admin.cc
@@ -2514,35 +2514,53 @@ static int bucket_source_sync_status(const DoutPrefixProvider *dpp, rgw::sal::Ra
 
   pipe.dest.bucket = bucket_info.bucket;
 
+  uint64_t gen = 0;
+  std::vector<rgw_bucket_shard_sync_info> shard_status;
+
+  // check for full sync status
   rgw_bucket_sync_status full_status;
   r = rgw_read_bucket_full_sync_status(dpp, store, pipe, &full_status, null_yield);
-  if (r < 0) {
+  if (r >= 0) {
+    if (full_status.state == BucketSyncState::Init) {
+      out << indented{width} << "init: bucket sync has not started\n";
+      return 0;
+    }
+    if (full_status.state == BucketSyncState::Stopped) {
+      out << indented{width} << "stopped: bucket sync is disabled\n";
+      return 0;
+    }
+    if (full_status.state == BucketSyncState::Full) {
+      out << indented{width} << "full sync: " << full_status.full.count << " objects completed\n";
+      return 0;
+    }
+    gen = full_status.incremental_gen;
+    shard_status.resize(full_status.shards_done_with_gen.size());
+  } else if (r == -ENOENT) {
+    // no full status, but there may be per-shard status from before upgrade
+    const auto& log = source_bucket->get_info().layout.logs.front();
+    if (log.gen > 0) {
+      // this isn't the backward-compatible case, so we just haven't started yet
+      out << indented{width} << "init: bucket sync has not started\n";
+      return 0;
+    }
+    if (log.layout.type != rgw::BucketLogType::InIndex) {
+      ldpp_dout(dpp, -1) << "unrecognized log layout type " << log.layout.type << dendl;
+      return -EINVAL;
+    }
+    // use shard count from our log gen=0
+    shard_status.resize(log.layout.in_index.layout.num_shards);
+  } else {
     lderr(store->ctx()) << "failed to read bucket full sync status: " << cpp_strerror(r) << dendl;
     return r;
   }
 
-  if (full_status.state == BucketSyncState::Init) {
-    out << indented{width} << "init: bucket sync has not started\n";
-    return 0;
-  }
-  if (full_status.state == BucketSyncState::Stopped) {
-    out << indented{width} << "stopped: bucket sync is disabled\n";
-    return 0;
-  }
-  if (full_status.state == BucketSyncState::Full) {
-    out << indented{width} << "full sync: " << full_status.full.count << " objects completed\n";
-    return 0;
-  }
-
-  std::vector<rgw_bucket_shard_sync_info> status;
-  status.resize(full_status.shards_done_with_gen.size());
-  r = rgw_read_bucket_inc_sync_status(dpp, store, pipe, full_status.incremental_gen, &status);
+  r = rgw_read_bucket_inc_sync_status(dpp, store, pipe, gen, &shard_status);
   if (r < 0) {
     lderr(store->ctx()) << "failed to read bucket incremental sync status: " << cpp_strerror(r) << dendl;
     return r;
   }
 
-  const size_t total_shards = status.size();
+  const size_t total_shards = shard_status.size();
 
   out << indented{width} << "incremental sync on " << total_shards << " shards\n";
 
@@ -2558,7 +2576,7 @@ static int bucket_source_sync_status(const DoutPrefixProvider *dpp, rgw::sal::Ra
   std::set<int> shards_behind;
   for (auto& r : remote_markers.get()) {
     auto shard_id = r.first;
-    auto& m = status[shard_id];
+    auto& m = shard_status[shard_id];
     if (r.second.empty()) {
       continue; // empty bucket index shard
     }
-- 
2.39.5