[PATCH 2/3] libxfs: remove map from libxfs_readbufr_map

[Brian Foster]

On 01/22/2014 02:17 AM, Dave Chinner wrote:
> From: Dave Chinner <dchinner at redhat.com>
> 
> The map passed in to libxfs_readbufr_map is used to check the buffer
> matches the map. However, the repair readahead code has no map it
> can use to validate the buffer it set up previously, so just get rid
> of the map being passed in because it serves no useful purpose.
> 

The code looks fine, effectively just removing some assert code, but I'm
not following the reasoning. I'm probably missing some context. Is the
justification that no callers of libxfs_readbufr_map() will actually
pass a map, or that the checking is not useful (redundant)?

Brian

> Signed-off-by: Dave Chinner <dchinner at redhat.com>
> ---
>  db/io.c          |  4 +---
>  include/libxfs.h |  3 +--
>  libxfs/rdwr.c    | 12 ++----------
>  3 files changed, 4 insertions(+), 15 deletions(-)
> 
> diff --git a/db/io.c b/db/io.c
> index 123214d..d29816c 100644
> --- a/db/io.c
> +++ b/db/io.c
> @@ -449,9 +449,7 @@ write_cur_bbs(void)
>  
>  
>  	/* re-read buffer from disk */
> -	ret = libxfs_readbufr_map(mp->m_ddev_targp, iocur_top->bp,
> -				  iocur_top->bbmap->b, iocur_top->bbmap->nmaps,
> -				  0);
> +	ret = libxfs_readbufr_map(mp->m_ddev_targp, iocur_top->bp, 0);
>  	if (ret != 0)
>  		dbprintf(_("read error: %s\n"), strerror(ret));
>  }
> diff --git a/include/libxfs.h b/include/libxfs.h
> index 2872410..bb0369f 100644
> --- a/include/libxfs.h
> +++ b/include/libxfs.h
> @@ -448,8 +448,7 @@ extern void	libxfs_putbufr(xfs_buf_t *);
>  extern int	libxfs_writebuf_int(xfs_buf_t *, int);
>  extern int	libxfs_writebufr(struct xfs_buf *);
>  extern int	libxfs_readbufr(struct xfs_buftarg *, xfs_daddr_t, xfs_buf_t *, int, int);
> -extern int	libxfs_readbufr_map(struct xfs_buftarg *, struct xfs_buf *,
> -				    struct xfs_buf_map *, int, int);
> +extern int	libxfs_readbufr_map(struct xfs_buftarg *, struct xfs_buf *, int);
>  
>  extern int libxfs_bhash_size;
>  
> diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c
> index bf92788..ac7739f 100644
> --- a/libxfs/rdwr.c
> +++ b/libxfs/rdwr.c
> @@ -727,27 +727,19 @@ libxfs_readbuf(struct xfs_buftarg *btp, xfs_daddr_t blkno, int len, int flags,
>  }
>  
>  int
> -libxfs_readbufr_map(struct xfs_buftarg *btp, struct xfs_buf *bp,
> -		    struct xfs_buf_map *map, int nmaps, int flags)
> +libxfs_readbufr_map(struct xfs_buftarg *btp, struct xfs_buf *bp, int flags)
>  {
>  	int	fd = libxfs_device_to_fd(btp->dev);
>  	int	error = 0;
>  	char	*buf;
>  	int	i;
>  
> -	ASSERT(BBTOB(len) <= bp->b_bcount);
> -
> -	ASSERT(bp->b_nmaps == nmaps);
> -
>  	fd = libxfs_device_to_fd(btp->dev);
>  	buf = bp->b_addr;
>  	for (i = 0; i < bp->b_nmaps; i++) {
>  		off64_t	offset = LIBXFS_BBTOOFF64(bp->b_map[i].bm_bn);
>  		int len = BBTOB(bp->b_map[i].bm_len);
>  
> -		ASSERT(bp->b_map[i].bm_bn == map[i].bm_bn);
> -		ASSERT(bp->b_map[i].bm_len == map[i].bm_len);
> -
>  		error = __read_buf(fd, buf, len, offset, flags);
>  		if (error) {
>  			bp->b_error = error;
> @@ -787,7 +779,7 @@ libxfs_readbuf_map(struct xfs_buftarg *btp, struct xfs_buf_map *map, int nmaps,
>  	if ((bp->b_flags & (LIBXFS_B_UPTODATE|LIBXFS_B_DIRTY)))
>  		return bp;
>  
> -	error = libxfs_readbufr_map(btp, bp, map, nmaps, flags);
> +	error = libxfs_readbufr_map(btp, bp, flags);
>  	if (!error) {
>  		bp->b_flags |= LIBXFS_B_UPTODATE;
>  		if (bp->b_ops)
>