xfs: convert XFS_AGFL_SIZE to a helper function

commit a78ee256c325ecfaec13cafc41b315bd4e1dd518 upstream.

The AGFL size calculation is about to get more complex, so lets turn
the macro into a function first and remove the macro.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
[darrick: forward port to newer kernel, simplify the helper]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

4 files changed, 28 insertions, 20 deletions

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index f965ce832bc0..8164eeb8db28 100644
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -52,6 +52,23 @@ STATIC int xfs_alloc_ag_vextent_size(xfs_alloc_arg_t *);
 STATIC int xfs_alloc_ag_vextent_small(xfs_alloc_arg_t *,
 		xfs_btree_cur_t *, xfs_agblock_t *, xfs_extlen_t *, int *);
 
+/*
+ * Size of the AGFL.  For CRC-enabled filesystes we steal a couple of slots in
+ * the beginning of the block for a proper header with the location information
+ * and CRC.
+ */
+unsigned int
+xfs_agfl_size(
+	struct xfs_mount	*mp)
+{
+	unsigned int		size = mp->m_sb.sb_sectsize;
+
+	if (xfs_sb_version_hascrc(&mp->m_sb))
+		size -= sizeof(struct xfs_agfl);
+
+	return size / sizeof(xfs_agblock_t);
+}
+
 unsigned int
 xfs_refc_block(
 	struct xfs_mount	*mp)
@@ -540,7 +557,7 @@ xfs_agfl_verify(
 	if (bp->b_pag && be32_to_cpu(agfl->agfl_seqno) != bp->b_pag->pag_agno)
 		return false;
 
-	for (i = 0; i < XFS_AGFL_SIZE(mp); i++) {
+	for (i = 0; i < xfs_agfl_size(mp); i++) {
 		if (be32_to_cpu(agfl->agfl_bno[i]) != NULLAGBLOCK &&
 		    be32_to_cpu(agfl->agfl_bno[i]) >= mp->m_sb.sb_agblocks)
 			return false;
@@ -2252,7 +2269,7 @@ xfs_alloc_get_freelist(
 	bno = be32_to_cpu(agfl_bno[be32_to_cpu(agf->agf_flfirst)]);
 	be32_add_cpu(&agf->agf_flfirst, 1);
 	xfs_trans_brelse(tp, agflbp);
-	if (be32_to_cpu(agf->agf_flfirst) == XFS_AGFL_SIZE(mp))
+	if (be32_to_cpu(agf->agf_flfirst) == xfs_agfl_size(mp))
 		agf->agf_flfirst = 0;
 
 	pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno));
@@ -2363,7 +2380,7 @@ xfs_alloc_put_freelist(
 			be32_to_cpu(agf->agf_seqno), &agflbp)))
 		return error;
 	be32_add_cpu(&agf->agf_fllast, 1);
-	if (be32_to_cpu(agf->agf_fllast) == XFS_AGFL_SIZE(mp))
+	if (be32_to_cpu(agf->agf_fllast) == xfs_agfl_size(mp))
 		agf->agf_fllast = 0;
 
 	pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno));
@@ -2381,7 +2398,7 @@ xfs_alloc_put_freelist(
 
 	xfs_alloc_log_agf(tp, agbp, logflags);
 
-	ASSERT(be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp));
+	ASSERT(be32_to_cpu(agf->agf_flcount) <= xfs_agfl_size(mp));
 
 	agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, agflbp);
 	blockp = &agfl_bno[be32_to_cpu(agf->agf_fllast)];
@@ -2414,9 +2431,9 @@ xfs_agf_verify(
 	if (!(agf->agf_magicnum == cpu_to_be32(XFS_AGF_MAGIC) &&
 	      XFS_AGF_GOOD_VERSION(be32_to_cpu(agf->agf_versionnum)) &&
 	      be32_to_cpu(agf->agf_freeblks) <= be32_to_cpu(agf->agf_length) &&
-	      be32_to_cpu(agf->agf_flfirst) < XFS_AGFL_SIZE(mp) &&
-	      be32_to_cpu(agf->agf_fllast) < XFS_AGFL_SIZE(mp) &&
-	      be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp)))
+	      be32_to_cpu(agf->agf_flfirst) < xfs_agfl_size(mp) &&
+	      be32_to_cpu(agf->agf_fllast) < xfs_agfl_size(mp) &&
+	      be32_to_cpu(agf->agf_flcount) <= xfs_agfl_size(mp)))
 		return false;
 
 	if (be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) < 1 ||
diff --git a/fs/xfs/libxfs/xfs_alloc.h b/fs/xfs/libxfs/xfs_alloc.h
index ef26edc2e938..346ba8ab68b5 100644
--- a/fs/xfs/libxfs/xfs_alloc.h
+++ b/fs/xfs/libxfs/xfs_alloc.h
@@ -26,6 +26,8 @@ struct xfs_trans;
 
 extern struct workqueue_struct *xfs_alloc_wq;
 
+unsigned int xfs_agfl_size(struct xfs_mount *mp);
+
 /*
  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
  */
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 23229f0c5b15..ed4481b2f113 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -798,24 +798,13 @@ typedef struct xfs_agi {
 		&(XFS_BUF_TO_AGFL(bp)->agfl_bno[0]) : \
 		(__be32 *)(bp)->b_addr)
 
-/*
- * Size of the AGFL.  For CRC-enabled filesystes we steal a couple of
- * slots in the beginning of the block for a proper header with the
- * location information and CRC.
- */
-#define XFS_AGFL_SIZE(mp) \
-	(((mp)->m_sb.sb_sectsize - \
-	 (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
-		sizeof(struct xfs_agfl) : 0)) / \
-	  sizeof(xfs_agblock_t))
-
 typedef struct xfs_agfl {
 	__be32		agfl_magicnum;
 	__be32		agfl_seqno;
 	uuid_t		agfl_uuid;
 	__be64		agfl_lsn;
 	__be32		agfl_crc;
-	__be32		agfl_bno[];	/* actually XFS_AGFL_SIZE(mp) */
+	__be32		agfl_bno[];	/* actually xfs_agfl_size(mp) */
 } __attribute__((packed)) xfs_agfl_t;
 
 #define XFS_AGFL_CRC_OFF	offsetof(struct xfs_agfl, agfl_crc)
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
index 8f22fc579dbb..40783a313df9 100644
--- a/fs/xfs/xfs_fsops.c
+++ b/fs/xfs/xfs_fsops.c
@@ -294,7 +294,7 @@ xfs_growfs_data_private(
 		}
 
 		agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, bp);
-		for (bucket = 0; bucket < XFS_AGFL_SIZE(mp); bucket++)
+		for (bucket = 0; bucket < xfs_agfl_size(mp); bucket++)
 			agfl_bno[bucket] = cpu_to_be32(NULLAGBLOCK);
 
 		error = xfs_bwrite(bp);