Re: [PATCH 4/5] Add loopback checkpoint support

[Eric Dumazet <eric.dumazet@gmail.com>]

Le mardi 16 février 2010 à 08:03 -0800, Dan Smith a écrit :
> Adds a small ndo_checkpoint() handler for loopback devices to write the
> name and addresses like other interfaces.
> 
> Signed-off-by: Dan Smith <danms@us.ibm.com>
> ---
>  drivers/net/loopback.c |   41 ++++++++++++++++++++++++++++++++++++++---
>  1 files changed, 38 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
> index b9fcc98..816a527 100644
> --- a/drivers/net/loopback.c
> +++ b/drivers/net/loopback.c
> @@ -57,6 +57,8 @@
>  #include <linux/ip.h>
>  #include <linux/tcp.h>
>  #include <linux/percpu.h>
> +#include <linux/checkpoint.h>
> +#include <linux/checkpoint_hdr.h>
>  #include <net/net_namespace.h>
>  
>  struct pcpu_lstats {
> @@ -153,10 +155,43 @@ static void loopback_dev_free(struct net_device *dev)
>  	free_netdev(dev);
>  }
>  

Dont you have a #ifdef CONFIG_CHECKPOINT or something to avoid this for
small machines ?

> +static int loopback_checkpoint(struct ckpt_ctx *ctx, struct net_device *dev)
> +{
> +	struct ckpt_hdr_netdev *h;
> +	struct ckpt_netdev_addr *addrs;
> +	int ret;
> +
> +	h = ckpt_netdev_base(ctx, dev, &addrs);
> +	if (IS_ERR(h))
> +		return PTR_ERR(h);
> +
> +	h->type = CKPT_NETDEV_LO;
> +
> +	ret = ckpt_write_obj(ctx, (struct ckpt_hdr *)h);
> +	if (ret < 0)
> +		goto out;
> +
> +	ret = ckpt_write_buffer(ctx, dev->name, IFNAMSIZ);
> +	if (ret < 0)
> +		goto out;
> +
> +	if (h->inet_addrs > 0) {
> +		int len = (sizeof(struct ckpt_netdev_addr) * h->inet_addrs);
> +		ret = ckpt_write_buffer(ctx, addrs, len);
> +	}
> +
> + out:
> +	ckpt_hdr_put(ctx, h);
> +	kfree(addrs);
> +
> +	return ret;
> +}
> +
>  static const struct net_device_ops loopback_ops = {
> -	.ndo_init      = loopback_dev_init,
> -	.ndo_start_xmit= loopback_xmit,
> -	.ndo_get_stats = loopback_get_stats,
> +	.ndo_init       = loopback_dev_init,
> +	.ndo_start_xmit = loopback_xmit,
> +	.ndo_get_stats  = loopback_get_stats,
> +	.ndo_checkpoint = loopback_checkpoint,
>  };
>  
>  /*