On Thu, Oct 10, 2024 at 02:29:00PM +0200, Laurent Vivier wrote:
> Extract pool storage initialization loop to tap_sock_update_pool(),
> extract QEMU hints to tap_backend_show_hints().
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

> ---
>  passt.c |  2 +-
>  tap.c   | 56 +++++++++++++++++++++++++++++++++++++++++---------------
>  tap.h   |  2 +-
>  3 files changed, 43 insertions(+), 17 deletions(-)
> 
> diff --git a/passt.c b/passt.c
> index ad6f0bc32df6..79093ee02d62 100644
> --- a/passt.c
> +++ b/passt.c
> @@ -261,7 +261,7 @@ int main(int argc, char **argv)
>  
>  	pasta_netns_quit_init(&c);
>  
> -	tap_sock_init(&c);
> +	tap_backend_init(&c);
>  
>  	secret_init(&c);
>  
> diff --git a/tap.c b/tap.c
> index c53a39b79e62..4b826fdf7adc 100644
> --- a/tap.c
> +++ b/tap.c
> @@ -1188,11 +1188,31 @@ int tap_sock_unix_open(char *sock_path)
>  	return fd;
>  }
>  
> +/**
> + * tap_backend_show_hints() - Give help information to start QEMU
> + * @c:		Execution context
> + */
> +static void tap_backend_show_hints(struct ctx *c)
> +{
> +	switch(c->mode) {
> +	case MODE_PASTA:
> +		/* No hints */
> +		break;
> +	case MODE_PASST:
> +		info("\nYou can now start qemu (>= 7.2, with commit 13c6be96618c):");
> +		info("    kvm ... -device virtio-net-pci,netdev=s -netdev stream,id=s,server=off,addr.type=unix,addr.path=%s",
> +		     c->sock_path);
> +		info("or qrap, for earlier qemu versions:");
> +		info("    ./qrap 5 kvm ... -net socket,fd=5 -net nic,model=virtio");
> +		break;
> +	}
> +}
> +
>  /**
>   * tap_sock_unix_init() - Start listening for connections on AF_UNIX socket
>   * @c:		Execution context
>   */
> -static void tap_sock_unix_init(struct ctx *c)
> +static void tap_sock_unix_init(const struct ctx *c)
>  {
>  	union epoll_ref ref = { .type = EPOLL_TYPE_TAP_LISTEN };
>  	struct epoll_event ev = { 0 };
> @@ -1203,12 +1223,6 @@ static void tap_sock_unix_init(struct ctx *c)
>  	ev.events = EPOLLIN | EPOLLET;
>  	ev.data.u64 = ref.u64;
>  	epoll_ctl(c->epollfd, EPOLL_CTL_ADD, c->fd_tap_listen, &ev);
> -
> -	info("\nYou can now start qemu (>= 7.2, with commit 13c6be96618c):");
> -	info("    kvm ... -device virtio-net-pci,netdev=s -netdev stream,id=s,server=off,addr.type=unix,addr.path=%s",
> -	     c->sock_path);
> -	info("or qrap, for earlier qemu versions:");
> -	info("    ./qrap 5 kvm ... -net socket,fd=5 -net nic,model=virtio");
>  }
>  
>  /**
> @@ -1321,21 +1335,31 @@ static void tap_sock_tun_init(struct ctx *c)
>  }
>  
>  /**
> - * tap_sock_init() - Create and set up AF_UNIX socket or tuntap file descriptor
> - * @c:		Execution context
> + * tap_sock_update_pool() - Set the buffer base and size for the pool of packets
> + * @base:	Buffer base
> + * @size	Buffer size
>   */
> -void tap_sock_init(struct ctx *c)
> +static void tap_sock_update_pool(void *base, size_t size)
>  {
> -	size_t sz = sizeof(pkt_buf);
>  	int i;
>  
> -	pool_tap4_storage = PACKET_INIT(pool_tap4, TAP_MSGS, pkt_buf, sz);
> -	pool_tap6_storage = PACKET_INIT(pool_tap6, TAP_MSGS, pkt_buf, sz);
> +	pool_tap4_storage = PACKET_INIT(pool_tap4, TAP_MSGS, base, size);
> +	pool_tap6_storage = PACKET_INIT(pool_tap6, TAP_MSGS, base, size);
>  
>  	for (i = 0; i < TAP_SEQS; i++) {
> -		tap4_l4[i].p = PACKET_INIT(pool_l4, UIO_MAXIOV, pkt_buf, sz);
> -		tap6_l4[i].p = PACKET_INIT(pool_l4, UIO_MAXIOV, pkt_buf, sz);
> +		tap4_l4[i].p = PACKET_INIT(pool_l4, UIO_MAXIOV, base, size);
> +		tap6_l4[i].p = PACKET_INIT(pool_l4, UIO_MAXIOV, base, size);
>  	}
> +}
> +
> +/**
> + * tap_backend_init() - Create and set up AF_UNIX socket or
> + *			tuntap file descriptor
> + * @c:		Execution context
> + */
> +void tap_backend_init(struct ctx *c)
> +{
> +	tap_sock_update_pool(pkt_buf, sizeof(pkt_buf));
>  
>  	if (c->fd_tap != -1) { /* Passed as --fd */
>  		struct epoll_event ev = { 0 };
> @@ -1365,4 +1389,6 @@ void tap_sock_init(struct ctx *c)
>  		 */
>  		memset(&c->guest_mac, 0xff, sizeof(c->guest_mac));
>  	}
> +
> +	tap_backend_show_hints(c);
>  }
> diff --git a/tap.h b/tap.h
> index 85f1e8473711..8728cc5c09c3 100644
> --- a/tap.h
> +++ b/tap.h
> @@ -68,7 +68,7 @@ void tap_handler_pasta(struct ctx *c, uint32_t events,
>  void tap_handler_passt(struct ctx *c, uint32_t events,
>  		       const struct timespec *now);
>  int tap_sock_unix_open(char *sock_path);
> -void tap_sock_init(struct ctx *c);
> +void tap_backend_init(struct ctx *c);
>  void tap_flush_pools(void);
>  void tap_handler(struct ctx *c, const struct timespec *now);
>  void tap_add_packet(struct ctx *c, ssize_t l2len, char *p);

-- 
David Gibson (he or they)	| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you, not the other way
				| around.
http://www.ozlabs.org/~dgibson