netdev - Re: [PATCH] ucc_geth: Convert to net_device

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 27 Mar 2009 13:50:30 -0500
From:	Timur Tabi <timur@...escale.com>
To:	Joakim Tjernlund <Joakim.Tjernlund@...nsmode.se>
Cc:	David Miller <davem@...emloft.net>, avorontsov@...mvista.com,
	leoli@...escale.com, linuxppc-dev@...abs.org,
	netdev@...r.kernel.org
Subject: Re: [PATCH] ucc_geth: Convert to net_device_ops

On Tue, Mar 24, 2009 at 6:08 PM, Joakim Tjernlund
<Joakim.Tjernlund@...nsmode.se> wrote:

> +       .ndo_change_mtu         = eth_change_mtu,

I have an old patch for change_mtu support for ucc_geth which I've
been meaning to push upstream.  This patch uses this function instead
of eth_change_mtu():

+static int ucc_geth_change_mtu(struct net_device *dev, int new_mtu)
+{
+	int max_rx_buf_length;
+	struct ucc_geth_private *ugeth = netdev_priv(dev);
+	int frame_size = new_mtu + 18;
+	struct ucc_geth_info *ug_info;
+	struct ucc_fast_info *uf_info;
+
+	if (ugeth->p_rx_glbl_pram) {
+		printk("%s: Interface is active!\n", __FUNCTION__);
+	} else {
+
+		ug_info = ugeth->ug_info;
+		uf_info = &ug_info->uf_info;
+
+		if ((frame_size < 64) || (frame_size > JUMBO_FRAME_SIZE)) {
+			printk(KERN_ERR "%s: Invalid MTU setting\n", dev->name);
+			return -EINVAL;
+		}
+
+		max_rx_buf_length =
+		    (frame_size & ~(UCC_GETH_MRBLR_ALIGNMENT - 1)) +
+		    UCC_GETH_MRBLR_ALIGNMENT;
+
+		ugeth->ug_info->uf_info.max_rx_buf_length = max_rx_buf_length;
+		dev->mtu = new_mtu;
+
+		/* Set the max. rx buffer size (MRBLR) */
+		uf_info->max_rx_buf_length = max_rx_buf_length;
+
+		/* set the max. frame length (MFLR) */
+		ug_info->maxFrameLength = frame_size;
+
+		ugeth_info("%s: MTU = %d (frame size=%d)\n", dev->name,
+		       dev->mtu, frame_size);
+	}
+	return 0;
+}

Do you think this is how it should be done?  I don't know enough about
ucc_geth and MTUs to know off-hand.

-- 
Timur Tabi
Linux kernel developer at Freescale
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html