xfs: factor out iclog size calculation from xlog_sync

Split out another self-contained bit of code from xlog_sync.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 150c65c..3534301 100644 (file)
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -1791,6 +1791,39 @@ xlog_split_iclog(
        return split_offset;
 }
 
+static int
+xlog_calc_iclog_size(
+       struct xlog             *log,
+       struct xlog_in_core     *iclog,
+       uint32_t                *roundoff)
+{
+       uint32_t                count_init, count;
+       bool                    use_lsunit;
+
+       use_lsunit = xfs_sb_version_haslogv2(&log->l_mp->m_sb) &&
+                       log->l_mp->m_sb.sb_logsunit > 1;
+
+       /* Add for LR header */
+       count_init = log->l_iclog_hsize + iclog->ic_offset;
+
+       /* Round out the log write size */
+       if (use_lsunit) {
+               /* we have a v2 stripe unit to use */
+               count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init));
+       } else {
+               count = BBTOB(BTOBB(count_init));
+       }
+
+       ASSERT(count >= count_init);
+       *roundoff = count - count_init;
+
+       if (use_lsunit)
+               ASSERT(*roundoff < log->l_mp->m_sb.sb_logsunit);
+       else
+               ASSERT(*roundoff < BBTOB(1));
+       return count;
+}
+
 /*
  * Flush out the in-core log (iclog) to the on-disk log in an asynchronous 
  * fashion.  Previously, we should have moved the current iclog
@@ -1819,35 +1852,17 @@ xlog_sync(
        struct xlog             *log,
        struct xlog_in_core     *iclog)
 {
-       uint            count;          /* byte count of bwrite */
-       uint            count_init;     /* initial count before roundup */
-       int             roundoff;       /* roundoff to BB or stripe */
-       int             v2 = xfs_sb_version_haslogv2(&log->l_mp->m_sb);
-       uint64_t        bno;
-       unsigned int    split = 0;
-       int             size;
-       bool            need_flush = true;
+       unsigned int            count;          /* byte count of bwrite */
+       unsigned int            roundoff;       /* roundoff to BB or stripe */
+       uint64_t                bno;
+       unsigned int            split = 0;
+       unsigned int            size;
+       bool                    need_flush = true;
 
        XFS_STATS_INC(log->l_mp, xs_log_writes);
        ASSERT(atomic_read(&iclog->ic_refcnt) == 0);
 
-       /* Add for LR header */
-       count_init = log->l_iclog_hsize + iclog->ic_offset;
-
-       /* Round out the log write size */
-       if (v2 && log->l_mp->m_sb.sb_logsunit > 1) {
-               /* we have a v2 stripe unit to use */
-               count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init));
-       } else {
-               count = BBTOB(BTOBB(count_init));
-       }
-       roundoff = count - count_init;
-       ASSERT(roundoff >= 0);
-       ASSERT((v2 && log->l_mp->m_sb.sb_logsunit > 1 && 
-                roundoff < log->l_mp->m_sb.sb_logsunit)
-               || 
-               (log->l_mp->m_sb.sb_logsunit <= 1 && 
-                roundoff < BBTOB(1)));
+       count = xlog_calc_iclog_size(log, iclog, &roundoff);
 
        /* move grant heads by roundoff in sync */
        xlog_grant_add_space(log, &log->l_reserve_head.grant, roundoff);
@@ -1858,7 +1873,7 @@ xlog_sync(
 
        /* real byte length */
        size = iclog->ic_offset;
-       if (v2)
+       if (xfs_sb_version_haslogv2(&log->l_mp->m_sb))
                size += roundoff;
        iclog->ic_header.h_len = cpu_to_be32(size);