diff --git a/pageserver/src/restore_local_repo.rs b/pageserver/src/restore_local_repo.rs
index 581be9c005..3677d4a3e4 100644
--- a/pageserver/src/restore_local_repo.rs
+++ b/pageserver/src/restore_local_repo.rs
@@ -3,6 +3,8 @@
 //! zenith Timeline.
 //!
 use log::*;
+use postgres_ffi::nonrelfile_utils::clogpage_precedes;
+use postgres_ffi::nonrelfile_utils::slru_may_delete_clogsegment;
 use std::cmp::min;
 use std::fs;
 use std::fs::File;
@@ -19,8 +21,8 @@ use crate::repository::*;
 use crate::waldecoder::*;
 use postgres_ffi::relfile_utils::*;
 use postgres_ffi::xlog_utils::*;
+use postgres_ffi::Oid;
 use postgres_ffi::{pg_constants, CheckPoint, ControlFileData};
-use postgres_ffi::{Oid, TransactionId};
 use zenith_utils::lsn::Lsn;
 
 const MAX_MBR_BLKNO: u32 =
@@ -736,44 +738,6 @@ fn save_xact_record(
     Ok(())
 }
 
-// See TransactionIdPrecedes in transam.c
-fn transaction_id_precedes(id1: TransactionId, id2: TransactionId) -> bool {
-    /*
-     * If either ID is a permanent XID then we can just do unsigned
-     * comparison.  If both are normal, do a modulo-2^32 comparison.
-     */
-
-    if !(id1 >= pg_constants::FIRST_NORMAL_TRANSACTION_ID)
-        || !(id2 >= pg_constants::FIRST_NORMAL_TRANSACTION_ID)
-    {
-        return id1 < id2;
-    }
-
-    let diff = id1.wrapping_sub(id2) as i32;
-    return diff < 0;
-}
-
-// See CLOGPagePrecedes in clog.c
-fn clogpage_precedes(page1: u32, page2: u32) -> bool {
-    let mut xid1 = page1 * pg_constants::CLOG_XACTS_PER_PAGE;
-    xid1 += pg_constants::FIRST_NORMAL_TRANSACTION_ID + 1;
-    let mut xid2 = page2 * pg_constants::CLOG_XACTS_PER_PAGE;
-    xid2 += pg_constants::FIRST_NORMAL_TRANSACTION_ID + 1;
-
-    return transaction_id_precedes(xid1, xid2)
-        && transaction_id_precedes(xid1, xid2 + pg_constants::CLOG_XACTS_PER_PAGE - 1);
-}
-
-// See SlruMayDeleteSegment() in slru.c
-fn slru_may_delete_clogsegment(segpage: u32, cutoff_page: u32) -> bool {
-    let seg_last_page = segpage + pg_constants::SLRU_PAGES_PER_SEGMENT - 1;
-
-    assert_eq!(segpage % pg_constants::SLRU_PAGES_PER_SEGMENT, 0);
-
-    return clogpage_precedes(segpage, cutoff_page)
-        && clogpage_precedes(seg_last_page, cutoff_page);
-}
-
 fn save_clog_truncate_record(
     checkpoint: &mut CheckPoint,
     timeline: &dyn Timeline,
diff --git a/postgres_ffi/src/lib.rs b/postgres_ffi/src/lib.rs
index d7fe9b951d..3021d4cf00 100644
--- a/postgres_ffi/src/lib.rs
+++ b/postgres_ffi/src/lib.rs
@@ -14,3 +14,23 @@ pub mod nonrelfile_utils;
 pub mod pg_constants;
 pub mod relfile_utils;
 pub mod xlog_utils;
+
+//  See TransactionIdIsNormal in transam.h
+pub const fn transaction_id_is_normal(id: TransactionId) -> bool {
+    id > pg_constants::FIRST_NORMAL_TRANSACTION_ID
+}
+
+// See TransactionIdPrecedes in transam.c
+pub const fn transaction_id_precedes(id1: TransactionId, id2: TransactionId) -> bool {
+    /*
+     * If either ID is a permanent XID then we can just do unsigned
+     * comparison.  If both are normal, do a modulo-2^32 comparison.
+     */
+
+    if !(transaction_id_is_normal(id1)) || !transaction_id_is_normal(id2) {
+        return id1 < id2;
+    }
+
+    let diff = id1.wrapping_sub(id2) as i32;
+    return diff < 0;
+}
diff --git a/postgres_ffi/src/nonrelfile_utils.rs b/postgres_ffi/src/nonrelfile_utils.rs
index a0dee29a9c..a0f1f61c18 100644
--- a/postgres_ffi/src/nonrelfile_utils.rs
+++ b/postgres_ffi/src/nonrelfile_utils.rs
@@ -1,7 +1,7 @@
 //!
 //! Common utilities for dealing with PostgreSQL non-relation files.
 //!
-use crate::pg_constants;
+use crate::{pg_constants, transaction_id_precedes};
 use bytes::BytesMut;
 use log::*;
 
@@ -30,3 +30,23 @@ pub fn transaction_id_get_status(xid: u32, page: &[u8]) -> u8 {
 
     ((page[byteno] >> bshift) & pg_constants::CLOG_XACT_BITMASK) as u8
 }
+
+// See CLOGPagePrecedes in clog.c
+pub const fn clogpage_precedes(page1: u32, page2: u32) -> bool {
+    let mut xid1 = page1 * pg_constants::CLOG_XACTS_PER_PAGE;
+    xid1 += pg_constants::FIRST_NORMAL_TRANSACTION_ID + 1;
+    let mut xid2 = page2 * pg_constants::CLOG_XACTS_PER_PAGE;
+    xid2 += pg_constants::FIRST_NORMAL_TRANSACTION_ID + 1;
+
+    transaction_id_precedes(xid1, xid2)
+        && transaction_id_precedes(xid1, xid2 + pg_constants::CLOG_XACTS_PER_PAGE - 1)
+}
+
+// See SlruMayDeleteSegment() in slru.c
+pub fn slru_may_delete_clogsegment(segpage: u32, cutoff_page: u32) -> bool {
+    let seg_last_page = segpage + pg_constants::SLRU_PAGES_PER_SEGMENT - 1;
+
+    assert_eq!(segpage % pg_constants::SLRU_PAGES_PER_SEGMENT, 0);
+
+    clogpage_precedes(segpage, cutoff_page) && clogpage_precedes(seg_last_page, cutoff_page)
+}