gfs2: Get rid of gfs2_log_header_in

Get rid of gfs2_log_header_in by integrating it into get_log_header.
Clean up the crc32 computations and use the same functions for encoding
and decoding to make things less confusing.  Eliminate lh_hash from
gfs2_log_header_host which is completely useless.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 9d4d736..e0557b8 100644 (file)
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -44,7 +44,6 @@ struct gfs2_log_header_host {
        u32 lh_flags;           /* GFS2_LOG_HEAD_... */
        u32 lh_tail;            /* Block number of log tail */
        u32 lh_blkno;
-       u32 lh_hash;
 };
 
 /*

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index b9889ae..c27cbce 100644 (file)
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -680,7 +680,7 @@ void gfs2_write_log_header(struct gfs2_sbd *sdp, u64 seq, u32 tail,
        lh->lh_flags = cpu_to_be32(flags);
        lh->lh_tail = cpu_to_be32(tail);
        lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
-       hash = gfs2_disk_hash(page_address(page), sizeof(struct gfs2_log_header));
+       hash = ~crc32(~0, lh, sizeof(*lh));
        lh->lh_hash = cpu_to_be32(hash);
 
        gfs2_log_write_page(sdp, page);

diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c
index 5d34312..975f321 100644 (file)
--- a/fs/gfs2/recovery.c
+++ b/fs/gfs2/recovery.c
@@ -118,22 +118,6 @@ void gfs2_revoke_clean(struct gfs2_jdesc *jd)
        }
 }
 
-static int gfs2_log_header_in(struct gfs2_log_header_host *lh, const void *buf)
-{
-       const struct gfs2_log_header *str = buf;
-
-       if (str->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
-           str->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH))
-               return 1;
-
-       lh->lh_sequence = be64_to_cpu(str->lh_sequence);
-       lh->lh_flags = be32_to_cpu(str->lh_flags);
-       lh->lh_tail = be32_to_cpu(str->lh_tail);
-       lh->lh_blkno = be32_to_cpu(str->lh_blkno);
-       lh->lh_hash = be32_to_cpu(str->lh_hash);
-       return 0;
-}
-
 /**
  * get_log_header - read the log header for a given segment
  * @jd: the journal
@@ -151,29 +135,33 @@ static int gfs2_log_header_in(struct gfs2_log_header_host *lh, const void *buf)
 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
                          struct gfs2_log_header_host *head)
 {
+       struct gfs2_log_header *lh;
        struct buffer_head *bh;
-       struct gfs2_log_header_host uninitialized_var(lh);
-       const u32 nothing = 0;
        u32 hash;
        int error;
 
        error = gfs2_replay_read_block(jd, blk, &bh);
        if (error)
                return error;
+       lh = (void *)bh->b_data;
 
-       hash = crc32_le((u32)~0, bh->b_data, sizeof(struct gfs2_log_header) -
-                                            sizeof(u32));
-       hash = crc32_le(hash, (unsigned char const *)&nothing, sizeof(nothing));
-       hash ^= (u32)~0;
-       error = gfs2_log_header_in(&lh, bh->b_data);
-       brelse(bh);
+       hash = crc32(~0, lh, sizeof(*lh) - 4);
+       hash = ~crc32_le_shift(hash, 4);  /* assume lh_hash is zero */
 
-       if (error || lh.lh_blkno != blk || lh.lh_hash != hash)
-               return 1;
+       error = lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
+               lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) ||
+               be32_to_cpu(lh->lh_blkno) != blk ||
+               be32_to_cpu(lh->lh_hash) != hash;
 
-       *head = lh;
+       brelse(bh);
 
-       return 0;
+       if (!error) {
+               head->lh_sequence = be64_to_cpu(lh->lh_sequence);
+               head->lh_flags = be32_to_cpu(lh->lh_flags);
+               head->lh_tail = be32_to_cpu(lh->lh_tail);
+               head->lh_blkno = be32_to_cpu(lh->lh_blkno);
+       }
+       return error;
 }
 
 /**