[Cluster-devel] [PATCH] gfs2_grow: write one rindex entry and then the rest

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

Looks good to me,

Steve.

On Thu, 2011-05-26 at 15:54 -0500, Benjamin Marzinski wrote:
> There is a problem with gfs2_grow when the rindex file is stuffed, or the
> filesystem blocksize is smaller than the pagesize. When gfs2_grow writes
> out all the rindex entries at once, there needs to be enough space left for
> it to be able to write the first page of data without doing any allocations.
> If there isn't gfs2_grow will fail, even though there is space for
> additional resrouce groups in the last block of the rindex file. This patch
> makes gfs2_grow write one rindex entry frist, to grow the filesystem by
> one resource group's worth of space. Then it writes the rest.  Since
> the code guarantees that there will always be enough space in the rindex
> file for one more rindex entry, the first write will never require an
> allocation.
> 
> Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
> ---
>  gfs2/mkfs/main_grow.c |   14 ++++++++++++--
>  1 files changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/gfs2/mkfs/main_grow.c b/gfs2/mkfs/main_grow.c
> index 03eb57b..81f492b 100644
> --- a/gfs2/mkfs/main_grow.c
> +++ b/gfs2/mkfs/main_grow.c
> @@ -244,8 +244,18 @@ static void fix_rindex(struct gfs2_sbd *sdp, int rindex_fd, int old_rg_count)
>  		}
>  		/* Now write the new RGs to the end of the rindex */
>  		lseek(rindex_fd, 0, SEEK_END);
> -		count = write(rindex_fd, buf, writelen);
> -		if (count != writelen) {
> +		count = write(rindex_fd, buf, sizeof(struct gfs2_rindex));
> +		if (count != sizeof(struct gfs2_rindex)) {
> +			log_crit("Error writing first new rindex entry;"
> +				 "aborted.\n");
> +			if (count > 0)
> +				goto trunc;
> +			else
> +				goto out;
> +		}
> +		count = write(rindex_fd, buf + sizeof(struct gfs2_rindex),
> +			      writelen - sizeof(struct gfs2_rindex));
> +		if (count != writelen - sizeof(struct gfs2_rindex)) {
>  			log_crit("Error writing new rindex entries;"
>  				 "aborted.\n");
>  			if (count > 0)