GFS2: introduce bi_blocks for optimization

This patch introduces a new field in the bitmap structure called
bi_blocks. Its purpose is to save us from constantly multiplying
bi_len by the constant GFS2_NBBY. It also paves the way for more
optimization in a future patch.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

2 files changed, 6 insertions, 1 deletions

diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 26aabd7caba7..f1a3243dfaf2 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -71,6 +71,7 @@ struct gfs2_bitmap {
         u32 bi_offset;
         u32 bi_start;
         u32 bi_len;
+        u32 bi_blocks;
 };
 
 struct gfs2_rgrpd {
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 7a6fa03bb32a..7d64a27683d9 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -262,7 +262,7 @@ static int gfs2_rbm_from_block(struct gfs2_rbm *rbm, u64 block)
         rbm->bi = rbm->rgd->rd_bits;
         rbm->offset = (u32)(rblock);
         /* Check if the block is within the first block */
-        if (rbm->offset < rbm->bi->bi_len * GFS2_NBBY)
+        if (rbm->offset < rbm->bi->bi_blocks)
                 return 0;
 
         /* Adjust for the size diff between gfs2_meta_header and gfs2_rgrp */
@@ -743,18 +743,21 @@ static int compute_bitstructs(struct gfs2_rgrpd *rgd)
                         bi->bi_offset = sizeof(struct gfs2_rgrp);
                         bi->bi_start = 0;
                         bi->bi_len = bytes;
+                        bi->bi_blocks = bytes * GFS2_NBBY;
                 /* header block */
                 } else if (x == 0) {
                         bytes = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_rgrp);
                         bi->bi_offset = sizeof(struct gfs2_rgrp);
                         bi->bi_start = 0;
                         bi->bi_len = bytes;
+                        bi->bi_blocks = bytes * GFS2_NBBY;
                 /* last block */
                 } else if (x + 1 == length) {
                         bytes = bytes_left;
                         bi->bi_offset = sizeof(struct gfs2_meta_header);
                         bi->bi_start = rgd->rd_bitbytes - bytes_left;
                         bi->bi_len = bytes;
+                        bi->bi_blocks = bytes * GFS2_NBBY;
                 /* other blocks */
                 } else {
                         bytes = sdp->sd_sb.sb_bsize -
@@ -762,6 +765,7 @@ static int compute_bitstructs(struct gfs2_rgrpd *rgd)
                         bi->bi_offset = sizeof(struct gfs2_meta_header);
                         bi->bi_start = rgd->rd_bitbytes - bytes_left;
                         bi->bi_len = bytes;
+                        bi->bi_blocks = bytes * GFS2_NBBY;
                 }
 
                 bytes_left -= bytes;