[PATCH] xfs: clean up calculation of LR header blocks

[Gao Xiang <hsiangkao@redhat.com>]

Let's use DIV_ROUND_UP() to calculate log record header
blocks as what did in xlog_get_iclog_buffer_size() and
also wrap up a common helper for log recovery code.

Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
---
 fs/xfs/libxfs/xfs_log_format.h | 10 +++++++++
 fs/xfs/xfs_log.c               |  4 +---
 fs/xfs/xfs_log_recover.c       | 37 ++++++++--------------------------
 3 files changed, 19 insertions(+), 32 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_log_format.h b/fs/xfs/libxfs/xfs_log_format.h
index e3400c9c71cd..f273a7db5702 100644
--- a/fs/xfs/libxfs/xfs_log_format.h
+++ b/fs/xfs/libxfs/xfs_log_format.h
@@ -860,4 +860,14 @@ struct xfs_icreate_log {
 	__be32		icl_gen;	/* inode generation number to use */
 };
 
+static inline int xlog_logv2_rec_hblks(struct xlog_rec_header *rh)
+{
+	int	h_size = be32_to_cpu(rh->h_size);
+
+	if ((be32_to_cpu(rh->h_version) & XLOG_VERSION_2) &&
+	    (h_size > XLOG_HEADER_CYCLE_SIZE))
+		return DIV_ROUND_UP(h_size, XLOG_HEADER_CYCLE_SIZE);
+	return 1;
+}
+
 #endif /* __XFS_LOG_FORMAT_H__ */
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index ad0c69ee8947..7a4ba408a3a2 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -1604,9 +1604,7 @@ xlog_cksum(
 		int		i;
 		int		xheads;
 
-		xheads = size / XLOG_HEADER_CYCLE_SIZE;
-		if (size % XLOG_HEADER_CYCLE_SIZE)
-			xheads++;
+		xheads = DIV_ROUND_UP(size, XLOG_HEADER_CYCLE_SIZE);
 
 		for (i = 1; i < xheads; i++) {
 			crc = crc32c(crc, &xhdr[i].hic_xheader,
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index e2ec91b2d0f4..5fecc0c7aeb2 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -489,15 +489,10 @@ xlog_find_verify_log_record(
 	 * reset last_blk.  Only when last_blk points in the middle of a log
 	 * record do we update last_blk.
 	 */
-	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
-		uint	h_size = be32_to_cpu(head->h_size);
-
-		xhdrs = h_size / XLOG_HEADER_CYCLE_SIZE;
-		if (h_size % XLOG_HEADER_CYCLE_SIZE)
-			xhdrs++;
-	} else {
+	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb))
+		xhdrs = xlog_logv2_rec_hblks(head);
+	else
 		xhdrs = 1;
-	}
 
 	if (*last_blk - i + extra_bblks !=
 	    BTOBB(be32_to_cpu(head->h_len)) + xhdrs)
@@ -1184,21 +1179,10 @@ xlog_check_unmount_rec(
 	 * below. We won't want to clear the unmount record if there is one, so
 	 * we pass the lsn of the unmount record rather than the block after it.
 	 */
-	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb)) {
-		int	h_size = be32_to_cpu(rhead->h_size);
-		int	h_version = be32_to_cpu(rhead->h_version);
-
-		if ((h_version & XLOG_VERSION_2) &&
-		    (h_size > XLOG_HEADER_CYCLE_SIZE)) {
-			hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
-			if (h_size % XLOG_HEADER_CYCLE_SIZE)
-				hblks++;
-		} else {
-			hblks = 1;
-		}
-	} else {
+	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb))
+		hblks = xlog_logv2_rec_hblks(rhead);
+	else
 		hblks = 1;
-	}
 
 	after_umount_blk = xlog_wrap_logbno(log,
 			rhead_blk + hblks + BTOBB(be32_to_cpu(rhead->h_len)));
@@ -3016,15 +3000,10 @@ xlog_do_recovery_pass(
 			}
 		}
 
-		if ((be32_to_cpu(rhead->h_version) & XLOG_VERSION_2) &&
-		    (h_size > XLOG_HEADER_CYCLE_SIZE)) {
-			hblks = h_size / XLOG_HEADER_CYCLE_SIZE;
-			if (h_size % XLOG_HEADER_CYCLE_SIZE)
-				hblks++;
+		hblks = xlog_logv2_rec_hblks(rhead);
+		if (hblks != 1) {
 			kmem_free(hbp);
 			hbp = xlog_alloc_buffer(log, hblks);
-		} else {
-			hblks = 1;
 		}
 	} else {
 		ASSERT(log->l_sectBBsize == 1);
-- 
2.18.1