diff --git a/fs/xfs/libxfs/xfs_ag_resv.c b/fs/xfs/libxfs/xfs_ag_resv.c
index 0ca2e680034a..03885a968de8 100644
--- a/fs/xfs/libxfs/xfs_ag_resv.c
+++ b/fs/xfs/libxfs/xfs_ag_resv.c
@@ -326,6 +326,8 @@ xfs_ag_resv_alloc_extent(
 	trace_xfs_ag_resv_alloc_extent(pag, type, args->len);
 
 	switch (type) {
+	case XFS_AG_RESV_AGFL:
+		return;
 	case XFS_AG_RESV_METADATA:
 	case XFS_AG_RESV_RMAPBT:
 		resv = xfs_perag_resv(pag, type);
@@ -366,6 +368,8 @@ xfs_ag_resv_free_extent(
 	trace_xfs_ag_resv_free_extent(pag, type, len);
 
 	switch (type) {
+	case XFS_AG_RESV_AGFL:
+		return;
 	case XFS_AG_RESV_METADATA:
 	case XFS_AG_RESV_RMAPBT:
 		resv = xfs_perag_resv(pag, type);
diff --git a/fs/xfs/libxfs/xfs_ag_resv.h b/fs/xfs/libxfs/xfs_ag_resv.h
index 8d6c687deef3..938f2f96c5e8 100644
--- a/fs/xfs/libxfs/xfs_ag_resv.h
+++ b/fs/xfs/libxfs/xfs_ag_resv.h
@@ -32,4 +32,35 @@ void xfs_ag_resv_alloc_extent(struct xfs_perag *pag, enum xfs_ag_resv_type type,
 void xfs_ag_resv_free_extent(struct xfs_perag *pag, enum xfs_ag_resv_type type,
 		struct xfs_trans *tp, xfs_extlen_t len);
 
+/*
+ * RMAPBT reservation accounting wrappers. Since rmapbt blocks are sourced from
+ * the AGFL, they are allocated one at a time and the reservation updates don't
+ * require a transaction.
+ */
+static inline void
+xfs_ag_resv_rmapbt_alloc(
+	struct xfs_mount	*mp,
+	xfs_agnumber_t		agno)
+{
+	struct xfs_alloc_arg	args = {0};
+	struct xfs_perag	*pag;
+
+	args.len = 1;
+	pag = xfs_perag_get(mp, agno);
+	xfs_ag_resv_alloc_extent(pag, XFS_AG_RESV_RMAPBT, &args);
+	xfs_perag_put(pag);
+}
+
+static inline void
+xfs_ag_resv_rmapbt_free(
+	struct xfs_mount	*mp,
+	xfs_agnumber_t		agno)
+{
+	struct xfs_perag	*pag;
+
+	pag = xfs_perag_get(mp, agno);
+	xfs_ag_resv_free_extent(pag, XFS_AG_RESV_RMAPBT, NULL, 1);
+	xfs_perag_put(pag);
+}
+
 #endif	/* __XFS_AG_RESV_H__ */
diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index e53d55453dc5..8c401efb2d74 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -711,7 +711,7 @@ xfs_alloc_ag_vextent(
 
 	ASSERT(args->len >= args->minlen);
 	ASSERT(args->len <= args->maxlen);
-	ASSERT(!args->wasfromfl || args->resv != XFS_AG_RESV_RMAPBT);
+	ASSERT(!args->wasfromfl || args->resv != XFS_AG_RESV_AGFL);
 	ASSERT(args->agbno % args->alignment == 0);
 
 	/* if not file data, insert new block into the reverse map btree */
@@ -1564,7 +1564,6 @@ xfs_alloc_ag_vextent_small(
 	int		*stat)	/* status: 0-freelist, 1-normal/none */
 {
 	struct xfs_owner_info	oinfo;
-	struct xfs_perag	*pag;
 	int		error;
 	xfs_agblock_t	fbno;
 	xfs_extlen_t	flen;
@@ -1583,7 +1582,7 @@ xfs_alloc_ag_vextent_small(
 	 * freelist.
 	 */
 	else if (args->minlen == 1 && args->alignment == 1 &&
-		 args->resv != XFS_AG_RESV_RMAPBT &&
+		 args->resv != XFS_AG_RESV_AGFL &&
 		 (be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_flcount)
 		  > args->minleft)) {
 		error = xfs_alloc_get_freelist(args->tp, args->agbp, &fbno, 0);
@@ -1616,18 +1615,13 @@ xfs_alloc_ag_vextent_small(
 			/*
 			 * If we're feeding an AGFL block to something that
 			 * doesn't live in the free space, we need to clear
-			 * out the OWN_AG rmap and add the block back to
-			 * the RMAPBT per-AG reservation.
+			 * out the OWN_AG rmap.
 			 */
 			xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_AG);
 			error = xfs_rmap_free(args->tp, args->agbp, args->agno,
 					fbno, 1, &oinfo);
 			if (error)
 				goto error0;
-			pag = xfs_perag_get(args->mp, args->agno);
-			xfs_ag_resv_free_extent(pag, XFS_AG_RESV_RMAPBT,
-					args->tp, 1);
-			xfs_perag_put(pag);
 
 			*stat = 0;
 			return 0;
@@ -2153,7 +2147,7 @@ xfs_alloc_fix_freelist(
 		if (error)
 			goto out_agbp_relse;
 		error = xfs_free_ag_extent(tp, agbp, args->agno, bno, 1,
-					   &targs.oinfo, XFS_AG_RESV_RMAPBT);
+					   &targs.oinfo, XFS_AG_RESV_AGFL);
 		if (error)
 			goto out_agbp_relse;
 		bp = xfs_btree_get_bufs(mp, tp, args->agno, bno, 0);
@@ -2179,7 +2173,7 @@ xfs_alloc_fix_freelist(
 	while (pag->pagf_flcount < need) {
 		targs.agbno = 0;
 		targs.maxlen = need - pag->pagf_flcount;
-		targs.resv = XFS_AG_RESV_RMAPBT;
+		targs.resv = XFS_AG_RESV_AGFL;
 
 		/* Allocate as many blocks as possible at once. */
 		error = xfs_alloc_ag_vextent(&targs);
@@ -2860,7 +2854,7 @@ xfs_free_extent(
 	int			error;
 
 	ASSERT(len != 0);
-	ASSERT(type != XFS_AG_RESV_RMAPBT);
+	ASSERT(type != XFS_AG_RESV_AGFL);
 
 	if (XFS_TEST_ERROR(false, mp,
 			XFS_ERRTAG_FREE_EXTENT))
diff --git a/fs/xfs/libxfs/xfs_rmap_btree.c b/fs/xfs/libxfs/xfs_rmap_btree.c
index e829c3e489ea..8560091554e0 100644
--- a/fs/xfs/libxfs/xfs_rmap_btree.c
+++ b/fs/xfs/libxfs/xfs_rmap_btree.c
@@ -130,6 +130,8 @@ xfs_rmapbt_alloc_block(
 	be32_add_cpu(&agf->agf_rmap_blocks, 1);
 	xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_RMAP_BLOCKS);
 
+	xfs_ag_resv_rmapbt_alloc(cur->bc_mp, cur->bc_private.a.agno);
+
 	XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 	*stat = 1;
 	return 0;
@@ -158,6 +160,8 @@ xfs_rmapbt_free_block(
 			      XFS_EXTENT_BUSY_SKIP_DISCARD);
 	xfs_trans_agbtree_delta(cur->bc_tp, -1);
 
+	xfs_ag_resv_rmapbt_free(cur->bc_mp, cur->bc_private.a.agno);
+
 	return 0;
 }
 
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index cf84288b65ca..7aae5af71aba 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -326,6 +326,7 @@ xfs_daddr_to_agbno(struct xfs_mount *mp, xfs_daddr_t d)
 /* per-AG block reservation data structures*/
 enum xfs_ag_resv_type {
 	XFS_AG_RESV_NONE = 0,
+	XFS_AG_RESV_AGFL,
 	XFS_AG_RESV_METADATA,
 	XFS_AG_RESV_RMAPBT,
 };
