1 files changed, 34 insertions, 144 deletions

diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c
index 0f501f938d1c..7389e445a7a7 100644
--- a/fs/gfs2/recovery.c
+++ b/fs/gfs2/recovery.c
@@ -120,6 +120,35 @@ void gfs2_revoke_clean(struct gfs2_jdesc *jd)
 	}
 }
 
+int __get_log_header(struct gfs2_sbd *sdp, const struct gfs2_log_header *lh,
+		     unsigned int blkno, struct gfs2_log_header_host *head)
+{
+	u32 hash, crc;
+
+	if (lh->lh_header.mh_magic != cpu_to_be32(GFS2_MAGIC) ||
+	    lh->lh_header.mh_type != cpu_to_be32(GFS2_METATYPE_LH) ||
+	    (blkno && be32_to_cpu(lh->lh_blkno) != blkno))
+		return 1;
+
+	hash = crc32(~0, lh, LH_V1_SIZE - 4);
+	hash = ~crc32_le_shift(hash, 4); /* assume lh_hash is zero */
+
+	if (be32_to_cpu(lh->lh_hash) != hash)
+		return 1;
+
+	crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
+		     sdp->sd_sb.sb_bsize - LH_V1_SIZE - 4);
+
+	if ((lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc))
+		return 1;
+
+	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 0;
+}
 /**
  * get_log_header - read the log header for a given segment
  * @jd: the journal
@@ -137,159 +166,18 @@ void gfs2_revoke_clean(struct gfs2_jdesc *jd)
 static int get_log_header(struct gfs2_jdesc *jd, unsigned int blk,
 			  struct gfs2_log_header_host *head)
 {
-	struct gfs2_log_header *lh;
+	struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 	struct buffer_head *bh;
-	u32 hash, crc;
 	int error;
 
 	error = gfs2_replay_read_block(jd, blk, &bh);
 	if (error)
 		return error;
-	lh = (void *)bh->b_data;
-
-	hash = crc32(~0, lh, LH_V1_SIZE - 4);
-	hash = ~crc32_le_shift(hash, 4);  /* assume lh_hash is zero */
-
-	crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
-		     bh->b_size - LH_V1_SIZE - 4);
-
-	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 ||
-		(lh->lh_crc != 0 && be32_to_cpu(lh->lh_crc) != crc);
 
+	error = __get_log_header(sdp, (const struct gfs2_log_header *)bh->b_data,
+				 blk, head);
 	brelse(bh);
 
-	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;
-}
-
-/**
- * find_good_lh - find a good log header
- * @jd: the journal
- * @blk: the segment to start searching from
- * @lh: the log header to fill in
- * @forward: if true search forward in the log, else search backward
- *
- * Call get_log_header() to get a log header for a segment, but if the
- * segment is bad, either scan forward or backward until we find a good one.
- *
- * Returns: errno
- */
-
-static int find_good_lh(struct gfs2_jdesc *jd, unsigned int *blk,
-			struct gfs2_log_header_host *head)
-{
-	unsigned int orig_blk = *blk;
-	int error;
-
-	for (;;) {
-		error = get_log_header(jd, *blk, head);
-		if (error <= 0)
-			return error;
-
-		if (++*blk == jd->jd_blocks)
-			*blk = 0;
-
-		if (*blk == orig_blk) {
-			gfs2_consist_inode(GFS2_I(jd->jd_inode));
-			return -EIO;
-		}
-	}
-}
-
-/**
- * jhead_scan - make sure we've found the head of the log
- * @jd: the journal
- * @head: this is filled in with the log descriptor of the head
- *
- * At this point, seg and lh should be either the head of the log or just
- * before.  Scan forward until we find the head.
- *
- * Returns: errno
- */
-
-static int jhead_scan(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
-{
-	unsigned int blk = head->lh_blkno;
-	struct gfs2_log_header_host lh;
-	int error;
-
-	for (;;) {
-		if (++blk == jd->jd_blocks)
-			blk = 0;
-
-		error = get_log_header(jd, blk, &lh);
-		if (error < 0)
-			return error;
-		if (error == 1)
-			continue;
-
-		if (lh.lh_sequence == head->lh_sequence) {
-			gfs2_consist_inode(GFS2_I(jd->jd_inode));
-			return -EIO;
-		}
-		if (lh.lh_sequence < head->lh_sequence)
-			break;
-
-		*head = lh;
-	}
-
-	return 0;
-}
-
-/**
- * gfs2_find_jhead - find the head of a log
- * @jd: the journal
- * @head: the log descriptor for the head of the log is returned here
- *
- * Do a binary search of a journal and find the valid log entry with the
- * highest sequence number.  (i.e. the log head)
- *
- * Returns: errno
- */
-
-int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head)
-{
-	struct gfs2_log_header_host lh_1, lh_m;
-	u32 blk_1, blk_2, blk_m;
-	int error;
-
-	blk_1 = 0;
-	blk_2 = jd->jd_blocks - 1;
-
-	for (;;) {
-		blk_m = (blk_1 + blk_2) / 2;
-
-		error = find_good_lh(jd, &blk_1, &lh_1);
-		if (error)
-			return error;
-
-		error = find_good_lh(jd, &blk_m, &lh_m);
-		if (error)
-			return error;
-
-		if (blk_1 == blk_m || blk_m == blk_2)
-			break;
-
-		if (lh_1.lh_sequence <= lh_m.lh_sequence)
-			blk_1 = blk_m;
-		else
-			blk_2 = blk_m;
-	}
-
-	error = jhead_scan(jd, &lh_1);
-	if (error)
-		return error;
-
-	*head = lh_1;
-
 	return error;
 }
 
@@ -460,6 +348,8 @@ void gfs2_recover_func(struct work_struct *work)
 	if (error)
 		goto fail_gunlock_ji;
 	t_jhd = ktime_get();
+	fs_info(sdp, "jid=%u: Journal head lookup took %lldms\n", jd->jd_jid,
+		ktime_ms_delta(t_jhd, t_jlck));
 
 	if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 		fs_info(sdp, "jid=%u: Acquiring the transaction lock...\n",