Re: [PATCH] virtio_blk: Add help function to format mass of disks

[Avi Kivity <avi@redhat.com>]

On 04/10/2012 10:28 AM, Ren Mingxin wrote:
> The current virtio block's naming algorithm just supports 18278
> (26^3 + 26^2 + 26) disks. If there are mass of virtio blocks,
> there will be disks with the same name.
>
> Based on commit 3e1a7ff8a0a7b948f2684930166954f9e8e776fe, I add
> function "virtblk_name_format()" for virtio block to support mass
> of disks naming.
>
> Signed-off-by: Ren Mingxin <renmx@cn.fujitsu.com>
> ---
>  drivers/block/virtio_blk.c |   38 ++++++++++++++++++++++++++------------
>  1 files changed, 26 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
> index c4a60ba..86516c8 100644
> --- a/drivers/block/virtio_blk.c
> +++ b/drivers/block/virtio_blk.c
> @@ -374,6 +374,31 @@ static int init_vq(struct virtio_blk *vblk)
>  	return err;
>  }
>  
> +static int virtblk_name_format(char *prefix, int index, char *buf, int buflen)
> +{
> +	const int base = 'z' - 'a' + 1;
> +	char *begin = buf + strlen(prefix);
> +	char *begin = buf + strlen(prefix);

Duplicate line.

> +	char *end = buf + buflen;
> +	char *p;
> +	int unit;
> +
> +	p = end - 1;
> +	*p = '\0';
> +	unit = base;

Why not use 'base' below?  neither unit nor base change.

> +	do {
> +		if (p == begin)
> +			return -EINVAL;
> +		*--p = 'a' + (index % unit);
> +		index = (index / unit) - 1;
> +	} while (index >= 0);
> +
> +	memmove(begin, p, end - p);
> +	memcpy(buf, prefix, strlen(prefix));
> +
> +	return 0;
> +}
> +
>

-- 
error compiling committee.c: too many arguments to function