From: Zhang Song <zhangsong325@gmail.com>
Date: Mon, 3 Apr 2023 11:29:27 +0000 (+0800)
Subject: crimson/os/seastore: avoid segment nonce collision
X-Git-Tag: v18.1.0~80^2~1
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=beb4812fa5b27999940e025fde8d591349c321bf;p=ceph-ci.git

crimson/os/seastore: avoid segment nonce collision

Signed-off-by: Zhang Song <zhangsong325@gmail.com>
(cherry picked from commit 367577efa7440d6d7414b9772a3b130109852535)
---

diff --git a/src/crimson/os/seastore/journal/segment_allocator.cc b/src/crimson/os/seastore/journal/segment_allocator.cc
index 5aeaad05c94..7ecbf486763 100644
--- a/src/crimson/os/seastore/journal/segment_allocator.cc
+++ b/src/crimson/os/seastore/journal/segment_allocator.cc
@@ -33,6 +33,17 @@ SegmentAllocator::SegmentAllocator(
   reset();
 }
 
+segment_nonce_t calc_new_nonce(
+  segment_type_t type,
+  uint32_t crc,
+  unsigned char const *data,
+  unsigned length)
+{
+  crc &= std::numeric_limits<uint32_t>::max() >> 1;
+  crc |= static_cast<uint32_t>(type) << 31;
+  return ceph_crc32c(crc, data, length);
+}
+
 SegmentAllocator::open_ret
 SegmentAllocator::do_open(bool is_mkfs)
 {
@@ -41,7 +52,8 @@ SegmentAllocator::do_open(bool is_mkfs)
   segment_seq_t new_segment_seq =
     segment_seq_allocator.get_and_inc_next_segment_seq();
   auto meta = sm_group.get_meta();
-  current_segment_nonce = ceph_crc32c(
+  current_segment_nonce = calc_new_nonce(
+    type,
     new_segment_seq,
     reinterpret_cast<const unsigned char *>(meta.seastore_id.bytes()),
     sizeof(meta.seastore_id.uuid));