[PATCH 5/5] ipv6: share sysctl net/ipv6/conf/DEVNAME/ tables
From: Lucian Adrian Grijincu
Date: Thu Feb 03 2011 - 23:38:25 EST
Similar to the ipv4 patch:
Before this, for each network device DEVNAME that supports ipv4 a new
sysctl table was registered in $PROC/sys/net/ipv6/conf/DEVNAME/.
The sysctl table was identical for all network devices, except for:
* data: pointer to the data to be accessed in the sysctl
* extra1: the 'struct inet6_dev*' of the network device
* extra2: the 'struct net*' of the network namespace
Assuming we have a device name and a 'struct net*', we can get the
'struct net_device*'. From there we can compute:
* data: each entry corresponds to a position in 'struct ipv6_devconf*'
* extra1: 'struct inet6_dev*' can be reached from 'struct net_device*'
* extra2: the 'struct net*' that we assume we have
The device name is determined from the path to the file (the name of
the parent dentry).
The 'struct net*' is stored in the parent 'struct ctl_table*' path by
register_net_sysctl_table_pathdata().
Signed-off-by: Lucian Adrian Grijincu <lucian.grijincu@xxxxxxxxx>
---
include/linux/ipv6.h | 15 ++++-
net/ipv6/addrconf.c | 192 +++++++++++++++++++++++++++++++++----------------
2 files changed, 143 insertions(+), 64 deletions(-)
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 0c99776..623761d 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -129,6 +129,17 @@ struct ipv6hdr {
};
#ifdef __KERNEL__
+
+#ifdef CONFIG_SYSCTL
+struct addrconf_sysctl {
+ /* dev_name holds a copy of dev_name, because '.procname' is
+ * regarded as const by sysctl and we wouldn't want anyone to
+ * change it under our feet (see SIOCSIFNAME). */
+ char *dev_name;
+ struct ctl_table_header *sysctl_header;
+};
+#endif
+
/*
* This structure contains configuration options per IPv6 link.
*/
@@ -172,7 +183,9 @@ struct ipv6_devconf {
__s32 disable_ipv6;
__s32 accept_dad;
__s32 force_tllao;
- void *sysctl;
+#ifdef CONFIG_SYSCTL
+ struct addrconf_sysctl addrconf_sysctl;
+#endif
};
struct ipv6_params {
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index fd6782e..27fd8a1 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -364,7 +364,8 @@ static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
ndev->cnf.mtu6 = dev->mtu;
- ndev->cnf.sysctl = NULL;
+ ndev->cnf.addrconf_sysctl.dev_name = NULL;
+ ndev->cnf.addrconf_sysctl.sysctl_header = NULL;
ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
if (ndev->nd_parms == NULL) {
kfree(ndev);
@@ -4249,90 +4250,176 @@ int addrconf_sysctl_disable(ctl_table *ctl, int write,
return ret;
}
-static struct addrconf_sysctl_table
+static int addrconf_handler(ctl_table *ctl, int write,
+ void __user *buffer,
+ size_t *lenp, loff_t *ppos,
+ struct file *filp,
+ proc_handler *proc_handler)
{
- struct ctl_table_header *sysctl_header;
- ctl_table addrconf_vars[DEVCONF_MAX+1];
- char *dev_name;
-} addrconf_sysctl __read_mostly = {
- .sysctl_header = NULL,
- .addrconf_vars = {
+ /* The path to this file is of the form:
+ * $PROC_MOUNT/sys/net/ipv6/conf/$DEVNAME/$CTL
+ *
+ * The array of 'struct ctl_table' of devinet entries is
+ * shared between all ipv6 network devices and the 'data'
+ * field of each structure only hold the offset into the
+ * 'data' field of 'struct ipv6_devconf'.
+ *
+ * To find the propper location of the data that must be
+ * accessed by this handler we need the device name and the
+ * network namespace in which it belongs.
+ */
+
+ /* We store the network namespace in the parent table's ->extra2 */
+ struct inode *parent_inode = filp->f_path.dentry->d_parent->d_inode;
+ struct ctl_table *parent_table = PROC_I(parent_inode)->sysctl_entry;
+ struct net *net = parent_table->extra2;
+
+ const char *dev_name = filp->f_path.dentry->d_parent->d_name.name;
+ struct ctl_table tmp_ctl;
+ struct net_device *dev = NULL;
+ struct inet6_dev *in6_dev = NULL;
+ struct ipv6_devconf *cnf;
+ int ret;
+
+ if (strcmp(dev_name, "all") == 0) {
+ cnf = net->ipv6.devconf_all;
+ } else if (strcmp(dev_name, "default") == 0) {
+ cnf = net->ipv6.devconf_dflt;
+ } else {
+ /* the device could have been renamed (SIOCSIFADDR) or
+ * deleted since we started accessing it's proc sysctl */
+ dev = dev_get_by_name(net, dev_name);
+ if (dev == NULL)
+ return -ENOENT;
+ in6_dev = in6_dev_get(dev);
+ cnf = &in6_dev->cnf;
+ }
+
+ tmp_ctl = *ctl;
+ tmp_ctl.data += (char *)cnf - (char *)&ipv6_devconf;
+ tmp_ctl.extra1 = in6_dev;
+ tmp_ctl.extra2 = net;
+
+ ret = proc_handler(&tmp_ctl, write, buffer, lenp, ppos);
+
+ if (in6_dev)
+ in6_dev_put(in6_dev);
+ if (dev)
+ dev_put(dev);
+ return ret;
+}
+
+
+static int addrconf_proc_dointvec(ctl_table *ctl, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos, struct file *filp)
+{
+ return addrconf_handler(ctl, write, buffer, lenp, ppos, filp,
+ proc_dointvec);
+}
+
+static int addrconf_proc_dointvec_jiffies(ctl_table *ctl, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos, struct file *filp)
+{
+ return addrconf_handler(ctl, write, buffer, lenp, ppos, filp,
+ proc_dointvec_jiffies);
+}
+
+static int addrconf_sysctl_forward__(ctl_table *ctl, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos, struct file *filp)
+{
+ return addrconf_handler(ctl, write, buffer, lenp, ppos, filp,
+ addrconf_sysctl_forward);
+}
+
+
+static int addrconf_sysctl_disable__(ctl_table *ctl, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos, struct file *filp)
+{
+ return addrconf_handler(ctl, write, buffer, lenp, ppos, filp,
+ addrconf_sysctl_disable);
+}
+
+static const struct ctl_table ipv6_addrconf_sysctl_table[DEVCONF_MAX+1] = {
{
.procname = "forwarding",
.data = &ipv6_devconf.forwarding,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = addrconf_sysctl_forward,
+ .proc_handler = addrconf_sysctl_forward__,
},
{
.procname = "hop_limit",
.data = &ipv6_devconf.hop_limit,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "mtu",
.data = &ipv6_devconf.mtu6,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "accept_ra",
.data = &ipv6_devconf.accept_ra,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "accept_redirects",
.data = &ipv6_devconf.accept_redirects,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "autoconf",
.data = &ipv6_devconf.autoconf,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "dad_transmits",
.data = &ipv6_devconf.dad_transmits,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "router_solicitations",
.data = &ipv6_devconf.rtr_solicits,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "router_solicitation_interval",
.data = &ipv6_devconf.rtr_solicit_interval,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
+ .proc_handler = addrconf_proc_dointvec_jiffies,
},
{
.procname = "router_solicitation_delay",
.data = &ipv6_devconf.rtr_solicit_delay,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
+ .proc_handler = addrconf_proc_dointvec_jiffies,
},
{
.procname = "force_mld_version",
.data = &ipv6_devconf.force_mld_version,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
#ifdef CONFIG_IPV6_PRIVACY
{
@@ -4340,35 +4427,35 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.use_tempaddr,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "temp_valid_lft",
.data = &ipv6_devconf.temp_valid_lft,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "temp_prefered_lft",
.data = &ipv6_devconf.temp_prefered_lft,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "regen_max_retry",
.data = &ipv6_devconf.regen_max_retry,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "max_desync_factor",
.data = &ipv6_devconf.max_desync_factor,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
#endif
{
@@ -4376,21 +4463,21 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.max_addresses,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "accept_ra_defrtr",
.data = &ipv6_devconf.accept_ra_defrtr,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "accept_ra_pinfo",
.data = &ipv6_devconf.accept_ra_pinfo,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
#ifdef CONFIG_IPV6_ROUTER_PREF
{
@@ -4398,14 +4485,14 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.accept_ra_rtr_pref,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "router_probe_interval",
.data = &ipv6_devconf.rtr_probe_interval,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
+ .proc_handler = addrconf_proc_dointvec_jiffies,
},
#ifdef CONFIG_IPV6_ROUTE_INFO
{
@@ -4413,7 +4500,7 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.accept_ra_rt_info_max_plen,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
#endif
#endif
@@ -4422,14 +4509,14 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.proxy_ndp,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "accept_source_route",
.data = &ipv6_devconf.accept_source_route,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
{
@@ -4437,7 +4524,7 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.optimistic_dad,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
#endif
@@ -4447,7 +4534,7 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.mc_forwarding,
.maxlen = sizeof(int),
.mode = 0444,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
#endif
{
@@ -4455,33 +4542,31 @@ static struct addrconf_sysctl_table
.data = &ipv6_devconf.disable_ipv6,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = addrconf_sysctl_disable,
+ .proc_handler = addrconf_sysctl_disable__,
},
{
.procname = "accept_dad",
.data = &ipv6_devconf.accept_dad,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_proc_dointvec,
},
{
.procname = "force_tllao",
.data = &ipv6_devconf.force_tllao,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .proc_handler = addrconf_proc_dointvec
},
{
/* sentinel */
}
- },
};
static int __addrconf_sysctl_register(struct net *net, char *dev_name,
struct inet6_dev *idev, struct ipv6_devconf *p)
{
- int i;
- struct addrconf_sysctl_table *t;
+ struct addrconf_sysctl *t = &p->addrconf_sysctl;
#define ADDRCONF_CTL_PATH_DEV 3
@@ -4494,16 +4579,6 @@ static int __addrconf_sysctl_register(struct net *net, char *dev_name,
};
- t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
- if (t == NULL)
- goto out;
-
- for (i = 0; t->addrconf_vars[i].data; i++) {
- t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
- t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
- t->addrconf_vars[i].extra2 = net;
- }
-
/*
* Make a copy of dev_name, because '.procname' is regarded as const
* by sysctl and we wouldn't want anyone to change it under our feet
@@ -4511,38 +4586,29 @@ static int __addrconf_sysctl_register(struct net *net, char *dev_name,
*/
t->dev_name = kstrdup(dev_name, GFP_KERNEL);
if (!t->dev_name)
- goto free;
+ goto out;
addrconf_ctl_path[ADDRCONF_CTL_PATH_DEV].procname = t->dev_name;
- t->sysctl_header = register_net_sysctl_table(net, addrconf_ctl_path,
- t->addrconf_vars);
+ t->sysctl_header = register_net_sysctl_table_pathdata(net,
+ addrconf_ctl_path, ipv6_addrconf_sysctl_table, net);
if (t->sysctl_header == NULL)
goto free_procname;
- p->sysctl = t;
return 0;
free_procname:
kfree(t->dev_name);
-free:
- kfree(t);
out:
return -ENOBUFS;
}
static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
{
- struct addrconf_sysctl_table *t;
-
- if (p->sysctl == NULL)
- return;
+ struct addrconf_sysctl *t = &p->addrconf_sysctl;
- t = p->sysctl;
- p->sysctl = NULL;
unregister_sysctl_table(t->sysctl_header);
kfree(t->dev_name);
- kfree(t);
}
static void addrconf_sysctl_register(struct inet6_dev *idev)
--
1.7.4.rc1.7.g2cf08.dirty
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