From 40e0e61e366bed56b71edb3b970245165090ec9a Mon Sep 17 00:00:00 2001 From: Abhi Das Date: Fri, 9 Nov 2018 09:54:18 -0600 Subject: [PATCH] gfs2: add a helper function to get_log_header that can be used elsewhere Move and re-order the error checks and hash/crc computations into another function __get_log_header() so it can be used in scenarios where buffer_heads are not being used for the log header. Signed-off-by: Abhi Das Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher --- fs/gfs2/recovery.c | 53 ++++++++++++++++++++++++++++------------------ fs/gfs2/recovery.h | 3 +++ 2 files changed, 35 insertions(+), 21 deletions(-) diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c index b0717a074543..2dac43065382 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 @@ -137,36 +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; } diff --git a/fs/gfs2/recovery.h b/fs/gfs2/recovery.h index 11fdfab4bf99..11d81248be85 100644 --- a/fs/gfs2/recovery.h +++ b/fs/gfs2/recovery.h @@ -31,6 +31,9 @@ extern int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head); extern int gfs2_recover_journal(struct gfs2_jdesc *gfs2_jd, bool wait); extern void gfs2_recover_func(struct work_struct *work); +extern int __get_log_header(struct gfs2_sbd *sdp, + const struct gfs2_log_header *lh, unsigned int blkno, + struct gfs2_log_header_host *head); #endif /* __RECOVERY_DOT_H__ */ -- 2.30.2