xfs: rename agfl perag res type to rmapbt

The AGFL perag reservation type accounts all allocations that feed
into (or are released from) the allocation group free list (agfl).
The purpose of the reservation is to support worst case conditions
for the reverse mapping btree (rmapbt). As such, the agfl
reservation usage accounting only considers rmapbt usage when the
in-core counters are initialized at mount time.

This implementation inconsistency leads to divergence of the in-core
and on-disk usage accounting over time. In preparation to resolve
this inconsistency and adjust the AGFL reservation into an rmapbt
specific reservation, rename the AGFL reservation type and
associated accounting fields to something more rmapbt-specific. Also
fix up a couple tracepoints that incorrectly use the AGFL
reservation type to pass the agfl state of the associated extent
where the raw reservation type is expected.

Note that this patch does not change perag reservation behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 44a63c5f43c8..a2cf3718bea9 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -326,7 +326,7 @@ xfs_daddr_to_agbno(struct xfs_mount *mp, xfs_daddr_t d)
 enum xfs_ag_resv_type {
 	XFS_AG_RESV_NONE = 0,
 	XFS_AG_RESV_METADATA,
-	XFS_AG_RESV_AGFL,
+	XFS_AG_RESV_RMAPBT,
 };
 
 struct xfs_ag_resv {
@@ -390,8 +390,8 @@ typedef struct xfs_perag {
 
 	/* Blocks reserved for all kinds of metadata. */
 	struct xfs_ag_resv	pag_meta_resv;
-	/* Blocks reserved for just AGFL-based metadata. */
-	struct xfs_ag_resv	pag_agfl_resv;
+	/* Blocks reserved for the reverse mapping btree. */
+	struct xfs_ag_resv	pag_rmapbt_resv;
 
 	/* reference count */
 	uint8_t			pagf_refcount_level;
@@ -405,8 +405,8 @@ xfs_perag_resv(
 	switch (type) {
 	case XFS_AG_RESV_METADATA:
 		return &pag->pag_meta_resv;
-	case XFS_AG_RESV_AGFL:
-		return &pag->pag_agfl_resv;
+	case XFS_AG_RESV_RMAPBT:
+		return &pag->pag_rmapbt_resv;
 	default:
 		return NULL;
 	}