Re: [Qemu-devel] [PATCH v5 2/6] nbd/server: refactor NBDExportMetaContexts

[Eric Blake <eblake@redhat.com>]

On 06/09/2018 10:17 AM, Vladimir Sementsov-Ogievskiy wrote:
> Use NBDExport pointer instead of just export name: there no needs to

s/no needs/is no need/

> store duplicated name in the struct, moreover, NBDExport will be used
> further.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   nbd/server.c | 23 +++++++++++------------
>   1 file changed, 11 insertions(+), 12 deletions(-)
> 

> @@ -399,10 +399,9 @@ static int nbd_negotiate_handle_list(NBDClient *client, Error **errp)
>       return nbd_negotiate_send_rep(client, NBD_REP_ACK, errp);
>   }
>   
> -static void nbd_check_meta_export_name(NBDClient *client)
> +static void nbd_check_meta_export(NBDClient *client)
>   {
> -    client->export_meta.valid &= !strcmp(client->exp->name,
> -                                         client->export_meta.export_name);
> +    client->export_meta.valid &= client->exp == client->export_meta.exp;

Changes from string comparison to pointer comparison...

> @@ -853,15 +852,15 @@ static int nbd_negotiate_meta_queries(NBDClient *client,
>   
>       memset(meta, 0, sizeof(*meta));
>   
> -    ret = nbd_opt_read_name(client, meta->export_name, NULL, errp);
> +    ret = nbd_opt_read_name(client, export_name, NULL, errp);
>       if (ret <= 0) {
>           return ret;
>       }
>   
> -    exp = nbd_export_find(meta->export_name);
> -    if (exp == NULL) {
> +    meta->exp = nbd_export_find(export_name);
> +    if (meta->exp == NULL) {

...by remembering the results of the string comparison performed under 
the hood.  Looks good.

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org