From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [RFC PATCH bridge 5/5] bridge: Add sysfs interface to display VLANS Date: Thu, 30 Aug 2012 10:51:35 -0400 Message-ID: <503F7DF7.5020606@redhat.com> References: <1345750195-31598-1-git-send-email-vyasevic@redhat.com> <1345750195-31598-6-git-send-email-vyasevic@redhat.com> <20120830122724.GC20228@redhat.com> <503F731C.1070208@redhat.com> <20120830142609.GE21132@redhat.com> <503F7A72.6070101@redhat.com> <20120830144443.GD21646@redhat.com> Reply-To: vyasevic@redhat.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: "Michael S. Tsirkin" Return-path: Received: from mx1.redhat.com ([209.132.183.28]:43819 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752455Ab2H3Ovg (ORCPT ); Thu, 30 Aug 2012 10:51:36 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q7UEpaEG011095 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 30 Aug 2012 10:51:36 -0400 In-Reply-To: <20120830144443.GD21646@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On 08/30/2012 10:44 AM, Michael S. Tsirkin wrote: > On Thu, Aug 30, 2012 at 10:36:34AM -0400, Vlad Yasevich wrote: >> On 08/30/2012 10:26 AM, Michael S. Tsirkin wrote: >>> On Thu, Aug 30, 2012 at 10:05:16AM -0400, Vlad Yasevich wrote: >>>> On 08/30/2012 08:27 AM, Michael S. Tsirkin wrote: >>>>> On Thu, Aug 23, 2012 at 03:29:55PM -0400, Vlad Yasevich wrote: >>>>>> Add a binary sysfs file that will dump out vlans currently configured on the >>>>>> port. >> >> I initially though of creating a sysfs object per vlan. That would >> have made it easy to see which vlans are configured without any >> tools. >> But that could result in a lot of objects being created, so I abandoned it. >> >> I did think about a text interface, but due to a page of output >> limitation, I didn't go that route. The reason is that if someone >> cats the file, they may not see all the vlans configured. So I >> decided on the binary interface, since a binary interface with a >> tool to read it could avoid the single page limitation. >> >> -vlad > > Maybe it's not needed in sysfs then - expose it to > brctl or whatever. > brctl uses sysfs for almost everything any more :) -vlad >>> >>> >>>>> >>>>>> --- >>>>>> include/linux/if_bridge.h | 1 + >>>>>> net/bridge/br_if.c | 34 ++++++++++++++++++++++++++++++++++ >>>>>> net/bridge/br_private.h | 2 ++ >>>>>> net/bridge/br_sysfs_if.c | 28 ++++++++++++++++++++++++++++ >>>>>> 4 files changed, 65 insertions(+), 0 deletions(-) >>>>>> >>>>>> diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h >>>>>> index ab750dd..d0f869b 100644 >>>>>> --- a/include/linux/if_bridge.h >>>>>> +++ b/include/linux/if_bridge.h >>>>>> @@ -20,6 +20,7 @@ >>>>>> #define SYSFS_BRIDGE_PORT_SUBDIR "brif" >>>>>> #define SYSFS_BRIDGE_PORT_ATTR "brport" >>>>>> #define SYSFS_BRIDGE_PORT_LINK "bridge" >>>>>> +#define SYSFS_BRIDGE_PORT_VLANS "vlans" >>>>>> >>>>>> #define BRCTL_VERSION 1 >>>>>> >>>>>> diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c >>>>>> index 90c1038..3963748 100644 >>>>>> --- a/net/bridge/br_if.c >>>>>> +++ b/net/bridge/br_if.c >>>>>> @@ -510,6 +510,40 @@ int br_del_port_vlan(struct net_bridge_port *p, unsigned long vlan) >>>>>> return 0; >>>>>> } >>>>>> >>>>>> +size_t br_port_fill_vlans(struct net_bridge_port *p, char* buf, >>>>>> + unsigned long max, unsigned long skip) >>>>>> +{ >>>>>> + unsigned long *map; >>>>>> + unsigned short *vid = (unsigned short *)buf; >>>>>> + unsigned short i; >>>>>> + int num = 0; >>>>>> + >>>>>> + if (skip > (VLAN_N_VID+1)) >>>>>> + return -EINVAL; >>>>>> + >>>>>> + memset(buf, 0, max * sizeof(unsigned short)); >>>>> >>>>> Isn't max is in bytes? why is this safe? >>>>> >>>>>> + >>>>>> + rcu_read_lock(); >>>>>> + map = rcu_dereference(p->vlan_map); >>>>>> + if (!map) >>>>>> + goto out; >>>>>> + >>>>>> + for (i = skip + 1; i < VLAN_N_VID + 1; i++) { >>>>> >>>>> Isn't skip in bytes too? Why do you compare it to i which is >>>>> in dwords? >>>>> >>>>>> + if (test_bit(i, map)) { >>>>>> + if (num > max) >>>>>> + goto out; >>>>>> + >>>>>> + *vid = i-1; >>>>>> + vid++; >>>>>> + num++; >>>>>> + } >>>>>> + } >>>>>> +out: >>>>>> + rcu_read_unlock(); >>>>>> + >>>>>> + return num*sizeof(unsigned short); >>>>>> +} >>>>>> + >>>>>> void __net_exit br_net_exit(struct net *net) >>>>>> { >>>>>> struct net_device *dev; >>>>>> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h >>>>>> index 5639c1c..cf95cd7 100644 >>>>>> --- a/net/bridge/br_private.h >>>>>> +++ b/net/bridge/br_private.h >>>>>> @@ -404,6 +404,8 @@ extern netdev_features_t br_features_recompute(struct net_bridge *br, >>>>>> netdev_features_t features); >>>>>> extern int br_set_port_vlan(struct net_bridge_port *p, unsigned long vid); >>>>>> extern int br_del_port_vlan(struct net_bridge_port *p, unsigned long vid); >>>>>> +extern size_t br_port_fill_vlans(struct net_bridge_port *p, char *buf, >>>>>> + unsigned long max, unsigned long skip); >>>>>> >>>>>> /* br_input.c */ >>>>>> extern int br_handle_frame_finish(struct sk_buff *skb); >>>>>> diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c >>>>>> index 13b36bd..a81e2ef 100644 >>>>>> --- a/net/bridge/br_sysfs_if.c >>>>>> +++ b/net/bridge/br_sysfs_if.c >>>>>> @@ -234,6 +234,29 @@ const struct sysfs_ops brport_sysfs_ops = { >>>>>> }; >>>>>> >>>>>> /* >>>>>> + * Export the vlan table for a given port as a binary file. >>>>>> + * The records are unsgined shorts. >>>>>> + * >>>>>> + * Returns the number of bytes read. >>>>>> + */ >>>>>> +static ssize_t brport_vlans_read(struct file *filp, struct kobject *kobj, >>>>>> + struct bin_attribute *bin_attr, >>>>>> + char *buf, loff_t off, size_t count) >>>>>> +{ >>>>>> + struct net_bridge_port *p = to_brport(kobj); >>>>>> + >>>>>> + return br_port_fill_vlans(p, buf, >>>>>> + count/sizeof(unsigned short), >>>>>> + off/sizeof(unsigned short)); >>>>>> +} >>>>>> + >>>>>> +static struct bin_attribute port_vlans = { >>>>>> + .attr = { .name = SYSFS_BRIDGE_PORT_VLANS, >>>>>> + .mode = S_IRUGO, }, >>>>>> + .read = brport_vlans_read, >>>>>> +}; >>>>>> + >>>>>> +/* >>>>>> * Add sysfs entries to ethernet device added to a bridge. >>>>>> * Creates a brport subdirectory with bridge attributes. >>>>>> * Puts symlink in bridge's brif subdirectory >>>>>> @@ -255,6 +278,11 @@ int br_sysfs_addif(struct net_bridge_port *p) >>>>>> return err; >>>>>> } >>>>>> >>>>>> + err = sysfs_create_bin_file(&p->kobj, &port_vlans); >>>>>> + if (err) { >>>>>> + return err; >>>>>> + } >>>>>> + >>>>>> strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ); >>>>>> return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name); >>>>>> } >>>>>> -- >>>>>> 1.7.7.6 >>>>>> >>>>>> -- >>>>>> To unsubscribe from this list: send the line "unsubscribe netdev" in >>>>>> the body of a message to majordomo@vger.kernel.org >>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html