[XFS] sanitize xlog_in_core_t definition

Move all fields from xlog_iclog_fields_t into xlog_in_core_t instead of having
them in a substructure and the using #defines to make it look like they were
directly in xlog_in_core_t.  Also document that xlog_in_core_2_t is grossly
misnamed, and make all references to it typesafe.

(First sent on Semptember 15th)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>

1 files changed, 13 insertions, 33 deletions

diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index b39a1980e82d..654167be0efb 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -310,6 +310,16 @@ typedef struct xlog_rec_ext_header {
 } xlog_rec_ext_header_t;
 
 #ifdef __KERNEL__
+
+/*
+ * Quite misnamed, because this union lays out the actual on-disk log buffer.
+ */
+typedef union xlog_in_core2 {
+        xlog_rec_header_t       hic_header;
+        xlog_rec_ext_header_t   hic_xheader;
+        char                    hic_sector[XLOG_HEADER_SIZE];
+} xlog_in_core_2_t;
+
 /*
  * - A log record header is 512 bytes.  There is plenty of room to grow the
  *      xlog_rec_header_t into the reserved space.
@@ -339,7 +349,7 @@ typedef struct xlog_rec_ext_header {
  * We'll put all the read-only and l_icloglock fields in the first cacheline,
  * and move everything else out to subsequent cachelines.
  */
-typedef struct xlog_iclog_fields {
+typedef struct xlog_in_core {
         sv_t                    ic_force_wait;
         sv_t                    ic_write_wait;
         struct xlog_in_core     *ic_next;
@@ -362,41 +372,11 @@ typedef struct xlog_iclog_fields {
 
         /* reference counts need their own cacheline */
         atomic_t                ic_refcnt ____cacheline_aligned_in_smp;
-} xlog_iclog_fields_t;
-
-typedef union xlog_in_core2 {
-        xlog_rec_header_t       hic_header;
-        xlog_rec_ext_header_t   hic_xheader;
-        char                    hic_sector[XLOG_HEADER_SIZE];
-} xlog_in_core_2_t;
-
-typedef struct xlog_in_core {
-        xlog_iclog_fields_t     hic_fields;
-        xlog_in_core_2_t        *hic_data;
+        xlog_in_core_2_t        *ic_data;
+#define ic_header       ic_data->hic_header
 } xlog_in_core_t;
 
 /*
- * Defines to save our code from this glop.
- */
-#define ic_force_wait   hic_fields.ic_force_wait
-#define ic_write_wait   hic_fields.ic_write_wait
-#define ic_next         hic_fields.ic_next
-#define ic_prev         hic_fields.ic_prev
-#define ic_bp           hic_fields.ic_bp
-#define ic_log          hic_fields.ic_log
-#define ic_callback     hic_fields.ic_callback
-#define ic_callback_lock hic_fields.ic_callback_lock
-#define ic_callback_tail hic_fields.ic_callback_tail
-#define ic_trace        hic_fields.ic_trace
-#define ic_size         hic_fields.ic_size
-#define ic_offset       hic_fields.ic_offset
-#define ic_refcnt       hic_fields.ic_refcnt
-#define ic_bwritecnt    hic_fields.ic_bwritecnt
-#define ic_state        hic_fields.ic_state
-#define ic_datap        hic_fields.ic_datap
-#define ic_header       hic_data->hic_header
-
-/*
  * The reservation head lsn is not made up of a cycle number and block number.
  * Instead, it uses a cycle number and byte number.  Logs don't expect to
  * overflow 31 bits worth of byte offset, so using a byte number will mean