linux/net/802/garp.c

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/*
* IEEE 802.1D Generic Attribute Registration Protocol (GARP)
*
* Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/llc.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <linux/module.h>
#include <net/llc.h>
#include <net/llc_pdu.h>
#include <net/garp.h>
#include <asm/unaligned.h>
static unsigned int garp_join_time __read_mostly = 200;
module_param(garp_join_time, uint, 0644);
MODULE_PARM_DESC(garp_join_time, "Join time in ms (default 200ms)");
MODULE_LICENSE("GPL");
static const struct garp_state_trans {
u8 state;
u8 action;
} garp_applicant_state_table[GARP_APPLICANT_MAX + 1][GARP_EVENT_MAX + 1] = {
[GARP_APPLICANT_VA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
},
[GARP_APPLICANT_AA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
},
[GARP_APPLICANT_QA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_LA },
},
[GARP_APPLICANT_LA] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_VO,
.action = GARP_ACTION_S_LEAVE_EMPTY },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_LA },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_LA },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_LA },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VA },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
[GARP_APPLICANT_VP] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_AA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AP },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_VO },
},
[GARP_APPLICANT_AP] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_QA,
.action = GARP_ACTION_S_JOIN_IN },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_AO },
},
[GARP_APPLICANT_QP] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QP },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_QO },
},
[GARP_APPLICANT_VO] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AO },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VP },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
[GARP_APPLICANT_AO] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_AP },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
[GARP_APPLICANT_QO] = {
[GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID },
[GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO },
[GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO },
[GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_QP },
[GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID },
},
};
static int garp_attr_cmp(const struct garp_attr *attr,
const void *data, u8 len, u8 type)
{
if (attr->type != type)
return attr->type - type;
if (attr->dlen != len)
return attr->dlen - len;
return memcmp(attr->data, data, len);
}
static struct garp_attr *garp_attr_lookup(const struct garp_applicant *app,
const void *data, u8 len, u8 type)
{
struct rb_node *parent = app->gid.rb_node;
struct garp_attr *attr;
int d;
while (parent) {
attr = rb_entry(parent, struct garp_attr, node);
d = garp_attr_cmp(attr, data, len, type);
if (d > 0)
parent = parent->rb_left;
else if (d < 0)
parent = parent->rb_right;
else
return attr;
}
return NULL;
}
static struct garp_attr *garp_attr_create(struct garp_applicant *app,
const void *data, u8 len, u8 type)
{
struct rb_node *parent = NULL, **p = &app->gid.rb_node;
struct garp_attr *attr;
int d;
while (*p) {
parent = *p;
attr = rb_entry(parent, struct garp_attr, node);
d = garp_attr_cmp(attr, data, len, type);
if (d > 0)
p = &parent->rb_left;
else if (d < 0)
p = &parent->rb_right;
else {
/* The attribute already exists; re-use it. */
return attr;
}
}
attr = kmalloc(sizeof(*attr) + len, GFP_ATOMIC);
if (!attr)
return attr;
attr->state = GARP_APPLICANT_VO;
attr->type = type;
attr->dlen = len;
memcpy(attr->data, data, len);
rb_link_node(&attr->node, parent, p);
rb_insert_color(&attr->node, &app->gid);
return attr;
}
static void garp_attr_destroy(struct garp_applicant *app, struct garp_attr *attr)
{
rb_erase(&attr->node, &app->gid);
kfree(attr);
}
static int garp_pdu_init(struct garp_applicant *app)
{
struct sk_buff *skb;
struct garp_pdu_hdr *gp;
#define LLC_RESERVE sizeof(struct llc_pdu_un)
skb = alloc_skb(app->dev->mtu + LL_RESERVED_SPACE(app->dev),
GFP_ATOMIC);
if (!skb)
return -ENOMEM;
skb->dev = app->dev;
skb->protocol = htons(ETH_P_802_2);
skb_reserve(skb, LL_RESERVED_SPACE(app->dev) + LLC_RESERVE);
gp = (struct garp_pdu_hdr *)__skb_put(skb, sizeof(*gp));
put_unaligned(htons(GARP_PROTOCOL_ID), &gp->protocol);
app->pdu = skb;
return 0;
}
static int garp_pdu_append_end_mark(struct garp_applicant *app)
{
if (skb_tailroom(app->pdu) < sizeof(u8))
return -1;
*(u8 *)__skb_put(app->pdu, sizeof(u8)) = GARP_END_MARK;
return 0;
}
static void garp_pdu_queue(struct garp_applicant *app)
{
if (!app->pdu)
return;
garp_pdu_append_end_mark(app);
garp_pdu_append_end_mark(app);
llc_pdu_header_init(app->pdu, LLC_PDU_TYPE_U, LLC_SAP_BSPAN,
LLC_SAP_BSPAN, LLC_PDU_CMD);
llc_pdu_init_as_ui_cmd(app->pdu);
llc_mac_hdr_init(app->pdu, app->dev->dev_addr,
app->app->proto.group_address);
skb_queue_tail(&app->queue, app->pdu);
app->pdu = NULL;
}
static void garp_queue_xmit(struct garp_applicant *app)
{
struct sk_buff *skb;
while ((skb = skb_dequeue(&app->queue)))
dev_queue_xmit(skb);
}
static int garp_pdu_append_msg(struct garp_applicant *app, u8 attrtype)
{
struct garp_msg_hdr *gm;
if (skb_tailroom(app->pdu) < sizeof(*gm))
return -1;
gm = (struct garp_msg_hdr *)__skb_put(app->pdu, sizeof(*gm));
gm->attrtype = attrtype;
garp_cb(app->pdu)->cur_type = attrtype;
return 0;
}
static int garp_pdu_append_attr(struct garp_applicant *app,
const struct garp_attr *attr,
enum garp_attr_event event)
{
struct garp_attr_hdr *ga;
unsigned int len;
int err;
again:
if (!app->pdu) {
err = garp_pdu_init(app);
if (err < 0)
return err;
}
if (garp_cb(app->pdu)->cur_type != attr->type) {
if (garp_cb(app->pdu)->cur_type &&
garp_pdu_append_end_mark(app) < 0)
goto queue;
if (garp_pdu_append_msg(app, attr->type) < 0)
goto queue;
}
len = sizeof(*ga) + attr->dlen;
if (skb_tailroom(app->pdu) < len)
goto queue;
ga = (struct garp_attr_hdr *)__skb_put(app->pdu, len);
ga->len = len;
ga->event = event;
memcpy(ga->data, attr->data, attr->dlen);
return 0;
queue:
garp_pdu_queue(app);
goto again;
}
static void garp_attr_event(struct garp_applicant *app,
struct garp_attr *attr, enum garp_event event)
{
enum garp_applicant_state state;
state = garp_applicant_state_table[attr->state][event].state;
if (state == GARP_APPLICANT_INVALID)
return;
switch (garp_applicant_state_table[attr->state][event].action) {
case GARP_ACTION_NONE:
break;
case GARP_ACTION_S_JOIN_IN:
/* When appending the attribute fails, don't update state in
* order to retry on next TRANSMIT_PDU event. */
if (garp_pdu_append_attr(app, attr, GARP_JOIN_IN) < 0)
return;
break;
case GARP_ACTION_S_LEAVE_EMPTY:
garp_pdu_append_attr(app, attr, GARP_LEAVE_EMPTY);
/* As a pure applicant, sending a leave message implies that
* the attribute was unregistered and can be destroyed. */
garp_attr_destroy(app, attr);
return;
default:
WARN_ON(1);
}
attr->state = state;
}
int garp_request_join(const struct net_device *dev,
const struct garp_application *appl,
const void *data, u8 len, u8 type)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
struct garp_attr *attr;
spin_lock_bh(&app->lock);
attr = garp_attr_create(app, data, len, type);
if (!attr) {
spin_unlock_bh(&app->lock);
return -ENOMEM;
}
garp_attr_event(app, attr, GARP_EVENT_REQ_JOIN);
spin_unlock_bh(&app->lock);
return 0;
}
EXPORT_SYMBOL_GPL(garp_request_join);
void garp_request_leave(const struct net_device *dev,
const struct garp_application *appl,
const void *data, u8 len, u8 type)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
struct garp_attr *attr;
spin_lock_bh(&app->lock);
attr = garp_attr_lookup(app, data, len, type);
if (!attr) {
spin_unlock_bh(&app->lock);
return;
}
garp_attr_event(app, attr, GARP_EVENT_REQ_LEAVE);
spin_unlock_bh(&app->lock);
}
EXPORT_SYMBOL_GPL(garp_request_leave);
static void garp_gid_event(struct garp_applicant *app, enum garp_event event)
{
struct rb_node *node, *next;
struct garp_attr *attr;
for (node = rb_first(&app->gid);
next = node ? rb_next(node) : NULL, node != NULL;
node = next) {
attr = rb_entry(node, struct garp_attr, node);
garp_attr_event(app, attr, event);
}
}
static void garp_join_timer_arm(struct garp_applicant *app)
{
unsigned long delay;
delay = (u64)msecs_to_jiffies(garp_join_time) * net_random() >> 32;
mod_timer(&app->join_timer, jiffies + delay);
}
static void garp_join_timer(unsigned long data)
{
struct garp_applicant *app = (struct garp_applicant *)data;
spin_lock(&app->lock);
garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
garp_pdu_queue(app);
spin_unlock(&app->lock);
garp_queue_xmit(app);
garp_join_timer_arm(app);
}
static int garp_pdu_parse_end_mark(struct sk_buff *skb)
{
if (!pskb_may_pull(skb, sizeof(u8)))
return -1;
if (*skb->data == GARP_END_MARK) {
skb_pull(skb, sizeof(u8));
return -1;
}
return 0;
}
static int garp_pdu_parse_attr(struct garp_applicant *app, struct sk_buff *skb,
u8 attrtype)
{
const struct garp_attr_hdr *ga;
struct garp_attr *attr;
enum garp_event event;
unsigned int dlen;
if (!pskb_may_pull(skb, sizeof(*ga)))
return -1;
ga = (struct garp_attr_hdr *)skb->data;
if (ga->len < sizeof(*ga))
return -1;
if (!pskb_may_pull(skb, ga->len))
return -1;
skb_pull(skb, ga->len);
dlen = sizeof(*ga) - ga->len;
if (attrtype > app->app->maxattr)
return 0;
switch (ga->event) {
case GARP_LEAVE_ALL:
if (dlen != 0)
return -1;
garp_gid_event(app, GARP_EVENT_R_LEAVE_EMPTY);
return 0;
case GARP_JOIN_EMPTY:
event = GARP_EVENT_R_JOIN_EMPTY;
break;
case GARP_JOIN_IN:
event = GARP_EVENT_R_JOIN_IN;
break;
case GARP_LEAVE_EMPTY:
event = GARP_EVENT_R_LEAVE_EMPTY;
break;
case GARP_EMPTY:
event = GARP_EVENT_R_EMPTY;
break;
default:
return 0;
}
if (dlen == 0)
return -1;
attr = garp_attr_lookup(app, ga->data, dlen, attrtype);
if (attr == NULL)
return 0;
garp_attr_event(app, attr, event);
return 0;
}
static int garp_pdu_parse_msg(struct garp_applicant *app, struct sk_buff *skb)
{
const struct garp_msg_hdr *gm;
if (!pskb_may_pull(skb, sizeof(*gm)))
return -1;
gm = (struct garp_msg_hdr *)skb->data;
if (gm->attrtype == 0)
return -1;
skb_pull(skb, sizeof(*gm));
while (skb->len > 0) {
if (garp_pdu_parse_attr(app, skb, gm->attrtype) < 0)
return -1;
if (garp_pdu_parse_end_mark(skb) < 0)
break;
}
return 0;
}
static void garp_pdu_rcv(const struct stp_proto *proto, struct sk_buff *skb,
struct net_device *dev)
{
struct garp_application *appl = proto->data;
struct garp_port *port;
struct garp_applicant *app;
const struct garp_pdu_hdr *gp;
port = rcu_dereference(dev->garp_port);
if (!port)
goto err;
app = rcu_dereference(port->applicants[appl->type]);
if (!app)
goto err;
if (!pskb_may_pull(skb, sizeof(*gp)))
goto err;
gp = (struct garp_pdu_hdr *)skb->data;
if (get_unaligned(&gp->protocol) != htons(GARP_PROTOCOL_ID))
goto err;
skb_pull(skb, sizeof(*gp));
spin_lock(&app->lock);
while (skb->len > 0) {
if (garp_pdu_parse_msg(app, skb) < 0)
break;
if (garp_pdu_parse_end_mark(skb) < 0)
break;
}
spin_unlock(&app->lock);
err:
kfree_skb(skb);
}
static int garp_init_port(struct net_device *dev)
{
struct garp_port *port;
port = kzalloc(sizeof(*port), GFP_KERNEL);
if (!port)
return -ENOMEM;
rcu_assign_pointer(dev->garp_port, port);
return 0;
}
static void garp_release_port(struct net_device *dev)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
unsigned int i;
for (i = 0; i <= GARP_APPLICATION_MAX; i++) {
if (rtnl_dereference(port->applicants[i]))
return;
}
RCU_INIT_POINTER(dev->garp_port, NULL);
kfree_rcu(port, rcu);
}
int garp_init_applicant(struct net_device *dev, struct garp_application *appl)
{
struct garp_applicant *app;
int err;
ASSERT_RTNL();
if (!rtnl_dereference(dev->garp_port)) {
err = garp_init_port(dev);
if (err < 0)
goto err1;
}
err = -ENOMEM;
app = kzalloc(sizeof(*app), GFP_KERNEL);
if (!app)
goto err2;
err = dev_mc_add(dev, appl->proto.group_address);
if (err < 0)
goto err3;
app->dev = dev;
app->app = appl;
app->gid = RB_ROOT;
spin_lock_init(&app->lock);
skb_queue_head_init(&app->queue);
rcu_assign_pointer(dev->garp_port->applicants[appl->type], app);
setup_timer(&app->join_timer, garp_join_timer, (unsigned long)app);
garp_join_timer_arm(app);
return 0;
err3:
kfree(app);
err2:
garp_release_port(dev);
err1:
return err;
}
EXPORT_SYMBOL_GPL(garp_init_applicant);
void garp_uninit_applicant(struct net_device *dev, struct garp_application *appl)
{
struct garp_port *port = rtnl_dereference(dev->garp_port);
struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]);
ASSERT_RTNL();
RCU_INIT_POINTER(port->applicants[appl->type], NULL);
/* Delete timer and generate a final TRANSMIT_PDU event to flush out
* all pending messages before the applicant is gone. */
del_timer_sync(&app->join_timer);
garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU);
garp_pdu_queue(app);
garp_queue_xmit(app);
dev_mc_del(dev, appl->proto.group_address);
kfree_rcu(app, rcu);
garp_release_port(dev);
}
EXPORT_SYMBOL_GPL(garp_uninit_applicant);
int garp_register_application(struct garp_application *appl)
{
appl->proto.rcv = garp_pdu_rcv;
appl->proto.data = appl;
return stp_proto_register(&appl->proto);
}
EXPORT_SYMBOL_GPL(garp_register_application);
void garp_unregister_application(struct garp_application *appl)
{
stp_proto_unregister(&appl->proto);
}
EXPORT_SYMBOL_GPL(garp_unregister_application);