xfs: record log sector size rather than log2(that)

Change struct log so it keeps track of the size (in basic blocks) of
a log sector in l_sectBBsize rather than the log-base-2 of that
value (previously, l_sectbb_log).  The name was chosen for
consistency with the other fields in the structure that represent
a number of basic blocks.

(Updated so that a variable used in computing and verifying a log's
sector size is named "log2_size".  Also added the "BB" to the
structure field name, based on feedback from Eric Sandeen.  Also
dropped some superfluous parentheses.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>

1 files changed, 18 insertions, 15 deletions

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 77593c2ead4d..36e09e362f7f 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -1039,6 +1039,7 @@ xlog_alloc_log(xfs_mount_t	*mp,
         int                     i;
         int                     iclogsize;
         int                     error = ENOMEM;
+        uint                    log2_size = 0;
 
         log = kmem_zalloc(sizeof(xlog_t), KM_MAYFAIL);
         if (!log) {
@@ -1064,29 +1065,31 @@ xlog_alloc_log(xfs_mount_t	*mp,
 
         error = EFSCORRUPTED;
         if (xfs_sb_version_hassector(&mp->m_sb)) {
-                log->l_sectbb_log = mp->m_sb.sb_logsectlog - BBSHIFT;
-                if (log->l_sectbb_log < 0 ||
-                    log->l_sectbb_log > mp->m_sectbb_log) {
-                        xlog_warn("XFS: Log sector size (0x%x) out of range.",
-                                                log->l_sectbb_log);
+                log2_size = mp->m_sb.sb_logsectlog;
+                if (log2_size < BBSHIFT) {
+                        xlog_warn("XFS: Log sector size too small "
+                                "(0x%x < 0x%x)", log2_size, BBSHIFT);
                         goto out_free_log;
                 }
 
-                /* for larger sector sizes, must have v2 or external log */
-                if (log->l_sectbb_log != 0 &&
-                    (log->l_logBBstart != 0 &&
-                     !xfs_sb_version_haslogv2(&mp->m_sb))) {
-                        xlog_warn("XFS: log sector size (0x%x) invalid "
-                                  "for configuration.", log->l_sectbb_log);
+                log2_size -= BBSHIFT;
+                if (log2_size > mp->m_sectbb_log) {
+                        xlog_warn("XFS: Log sector size too large "
+                                "(0x%x > 0x%x)", log2_size, mp->m_sectbb_log);
                         goto out_free_log;
                 }
-                if (mp->m_sb.sb_logsectlog < BBSHIFT) {
-                        xlog_warn("XFS: Log sector log (0x%x) too small.",
-                                                mp->m_sb.sb_logsectlog);
+
+                /* for larger sector sizes, must have v2 or external log */
+                if (log2_size && log->l_logBBstart > 0 &&
+                            !xfs_sb_version_haslogv2(&mp->m_sb)) {
+
+                        xlog_warn("XFS: log sector size (0x%x) invalid "
+                                  "for configuration.", log2_size);
                         goto out_free_log;
                 }
         }
-        log->l_sectbb_mask = (1 << log->l_sectbb_log) - 1;
+        log->l_sectBBsize = 1 << log2_size;
+        log->l_sectbb_mask = log->l_sectBBsize - 1;
 
         xlog_get_iclog_buffer_size(mp, log);