[linux-block.git] / net / core / dst.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * net/core/dst.c	Protocol independent destination cache.
 *
 * Authors:		Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 */

#include <linux/bitops.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/workqueue.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/string.h>
#include <linux/types.h>
#include <net/net_namespace.h>
#include <linux/sched.h>
#include <linux/prefetch.h>
#include <net/lwtunnel.h>
#include <net/xfrm.h>

#include <net/dst.h>
#include <net/dst_metadata.h>

int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb)
{
	kfree_skb(skb);
	return 0;
}
EXPORT_SYMBOL(dst_discard_out);

const struct dst_metrics dst_default_metrics = {
	/* This initializer is needed to force linker to place this variable
	 * into const section. Otherwise it might end into bss section.
	 * We really want to avoid false sharing on this variable, and catch
	 * any writes on it.
	 */
	.refcnt = REFCOUNT_INIT(1),
};
EXPORT_SYMBOL(dst_default_metrics);

void dst_init(struct dst_entry *dst, struct dst_ops *ops,
	      struct net_device *dev, int initial_obsolete,
	      unsigned short flags)
{
	dst->dev = dev;
	netdev_hold(dev, &dst->dev_tracker, GFP_ATOMIC);
	dst->ops = ops;
	dst_init_metrics(dst, dst_default_metrics.metrics, true);
	dst->expires = 0UL;
#ifdef CONFIG_XFRM
	dst->xfrm = NULL;
#endif
	dst->input = dst_discard;
	dst->output = dst_discard_out;
	dst->error = 0;
	dst->obsolete = initial_obsolete;
	dst->header_len = 0;
	dst->trailer_len = 0;
#ifdef CONFIG_IP_ROUTE_CLASSID
	dst->tclassid = 0;
#endif
	dst->lwtstate = NULL;
	rcuref_init(&dst->__rcuref, 1);
	INIT_LIST_HEAD(&dst->rt_uncached);
	dst->__use = 0;
	dst->lastuse = jiffies;
	dst->flags = flags;
	if (!(flags & DST_NOCOUNT))
		dst_entries_add(ops, 1);
}
EXPORT_SYMBOL(dst_init);

void *dst_alloc(struct dst_ops *ops, struct net_device *dev,
		int initial_obsolete, unsigned short flags)
{
	struct dst_entry *dst;

	if (ops->gc &&
	    !(flags & DST_NOCOUNT) &&
	    dst_entries_get_fast(ops) > ops->gc_thresh)
		ops->gc(ops);

	dst = kmem_cache_alloc(ops->kmem_cachep, GFP_ATOMIC);
	if (!dst)
		return NULL;

	dst_init(dst, ops, dev, initial_obsolete, flags);

	return dst;
}
EXPORT_SYMBOL(dst_alloc);

struct dst_entry *dst_destroy(struct dst_entry * dst)
{
	struct dst_entry *child = NULL;

	smp_rmb();

#ifdef CONFIG_XFRM
	if (dst->xfrm) {
		struct xfrm_dst *xdst = (struct xfrm_dst *) dst;

		child = xdst->child;
	}
#endif
	if (!(dst->flags & DST_NOCOUNT))
		dst_entries_add(dst->ops, -1);

	if (dst->ops->destroy)
		dst->ops->destroy(dst);
	netdev_put(dst->dev, &dst->dev_tracker);

	lwtstate_put(dst->lwtstate);

	if (dst->flags & DST_METADATA)
		metadata_dst_free((struct metadata_dst *)dst);
	else
		kmem_cache_free(dst->ops->kmem_cachep, dst);

	dst = child;
	if (dst)
		dst_release_immediate(dst);
	return NULL;
}
EXPORT_SYMBOL(dst_destroy);

static void dst_destroy_rcu(struct rcu_head *head)
{
	struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);

	dst = dst_destroy(dst);
}

/* Operations to mark dst as DEAD and clean up the net device referenced
 * by dst:
 * 1. put the dst under blackhole interface and discard all tx/rx packets
 *    on this route.
 * 2. release the net_device
 * This function should be called when removing routes from the fib tree
 * in preparation for a NETDEV_DOWN/NETDEV_UNREGISTER event and also to
 * make the next dst_ops->check() fail.
 */
void dst_dev_put(struct dst_entry *dst)
{
	struct net_device *dev = dst->dev;

	dst->obsolete = DST_OBSOLETE_DEAD;
	if (dst->ops->ifdown)
		dst->ops->ifdown(dst, dev);
	dst->input = dst_discard;
	dst->output = dst_discard_out;
	dst->dev = blackhole_netdev;
	netdev_ref_replace(dev, blackhole_netdev, &dst->dev_tracker,
			   GFP_ATOMIC);
}
EXPORT_SYMBOL(dst_dev_put);

void dst_release(struct dst_entry *dst)
{
	if (dst && rcuref_put(&dst->__rcuref))
		call_rcu_hurry(&dst->rcu_head, dst_destroy_rcu);
}
EXPORT_SYMBOL(dst_release);

void dst_release_immediate(struct dst_entry *dst)
{
	if (dst && rcuref_put(&dst->__rcuref))
		dst_destroy(dst);
}
EXPORT_SYMBOL(dst_release_immediate);

u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old)
{
	struct dst_metrics *p = kmalloc(sizeof(*p), GFP_ATOMIC);

	if (p) {
		struct dst_metrics *old_p = (struct dst_metrics *)__DST_METRICS_PTR(old);
		unsigned long prev, new;

		refcount_set(&p->refcnt, 1);
		memcpy(p->metrics, old_p->metrics, sizeof(p->metrics));

		new = (unsigned long) p;
		prev = cmpxchg(&dst->_metrics, old, new);

		if (prev != old) {
			kfree(p);
			p = (struct dst_metrics *)__DST_METRICS_PTR(prev);
			if (prev & DST_METRICS_READ_ONLY)
				p = NULL;
		} else if (prev & DST_METRICS_REFCOUNTED) {
			if (refcount_dec_and_test(&old_p->refcnt))
				kfree(old_p);
		}
	}
	BUILD_BUG_ON(offsetof(struct dst_metrics, metrics) != 0);
	return (u32 *)p;
}
EXPORT_SYMBOL(dst_cow_metrics_generic);

/* Caller asserts that dst_metrics_read_only(dst) is false.  */
void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old)
{
	unsigned long prev, new;

	new = ((unsigned long) &dst_default_metrics) | DST_METRICS_READ_ONLY;
	prev = cmpxchg(&dst->_metrics, old, new);
	if (prev == old)
		kfree(__DST_METRICS_PTR(old));
}
EXPORT_SYMBOL(__dst_destroy_metrics_generic);

struct dst_entry *dst_blackhole_check(struct dst_entry *dst, u32 cookie)
{
	return NULL;
}

u32 *dst_blackhole_cow_metrics(struct dst_entry *dst, unsigned long old)
{
	return NULL;
}

struct neighbour *dst_blackhole_neigh_lookup(const struct dst_entry *dst,
					     struct sk_buff *skb,
					     const void *daddr)
{
	return NULL;
}

void dst_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
			       struct sk_buff *skb, u32 mtu,
			       bool confirm_neigh)
{
}
EXPORT_SYMBOL_GPL(dst_blackhole_update_pmtu);

void dst_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
			    struct sk_buff *skb)
{
}
EXPORT_SYMBOL_GPL(dst_blackhole_redirect);

unsigned int dst_blackhole_mtu(const struct dst_entry *dst)
{
	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);

	return mtu ? : dst->dev->mtu;
}
EXPORT_SYMBOL_GPL(dst_blackhole_mtu);

static struct dst_ops dst_blackhole_ops = {
	.family		= AF_UNSPEC,
	.neigh_lookup	= dst_blackhole_neigh_lookup,
	.check		= dst_blackhole_check,
	.cow_metrics	= dst_blackhole_cow_metrics,
	.update_pmtu	= dst_blackhole_update_pmtu,
	.redirect	= dst_blackhole_redirect,
	.mtu		= dst_blackhole_mtu,
};

static void __metadata_dst_init(struct metadata_dst *md_dst,
				enum metadata_type type, u8 optslen)
{
	struct dst_entry *dst;

	dst = &md_dst->dst;
	dst_init(dst, &dst_blackhole_ops, NULL, DST_OBSOLETE_NONE,
		 DST_METADATA | DST_NOCOUNT);
	memset(dst + 1, 0, sizeof(*md_dst) + optslen - sizeof(*dst));
	md_dst->type = type;
}

struct metadata_dst *metadata_dst_alloc(u8 optslen, enum metadata_type type,
					gfp_t flags)
{
	struct metadata_dst *md_dst;

	md_dst = kmalloc(sizeof(*md_dst) + optslen, flags);
	if (!md_dst)
		return NULL;

	__metadata_dst_init(md_dst, type, optslen);

	return md_dst;
}
EXPORT_SYMBOL_GPL(metadata_dst_alloc);

void metadata_dst_free(struct metadata_dst *md_dst)
{
#ifdef CONFIG_DST_CACHE
	if (md_dst->type == METADATA_IP_TUNNEL)
		dst_cache_destroy(&md_dst->u.tun_info.dst_cache);
#endif
	if (md_dst->type == METADATA_XFRM)
		dst_release(md_dst->u.xfrm_info.dst_orig);
	kfree(md_dst);
}
EXPORT_SYMBOL_GPL(metadata_dst_free);

struct metadata_dst __percpu *
metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags)
{
	int cpu;
	struct metadata_dst __percpu *md_dst;

	md_dst = __alloc_percpu_gfp(sizeof(struct metadata_dst) + optslen,
				    __alignof__(struct metadata_dst), flags);
	if (!md_dst)
		return NULL;

	for_each_possible_cpu(cpu)
		__metadata_dst_init(per_cpu_ptr(md_dst, cpu), type, optslen);

	return md_dst;
}
EXPORT_SYMBOL_GPL(metadata_dst_alloc_percpu);

void metadata_dst_free_percpu(struct metadata_dst __percpu *md_dst)
{
	int cpu;

	for_each_possible_cpu(cpu) {
		struct metadata_dst *one_md_dst = per_cpu_ptr(md_dst, cpu);

#ifdef CONFIG_DST_CACHE
		if (one_md_dst->type == METADATA_IP_TUNNEL)
			dst_cache_destroy(&one_md_dst->u.tun_info.dst_cache);
#endif
		if (one_md_dst->type == METADATA_XFRM)
			dst_release(one_md_dst->u.xfrm_info.dst_orig);
	}
	free_percpu(md_dst);
}
EXPORT_SYMBOL_GPL(metadata_dst_free_percpu);
Commit	Line	Data
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
1da177e4 LT	2	/*
	3	* net/core/dst.c Protocol independent destination cache.
	4	*
	5	* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
	6	*
	7	*/
	8
	9	#include <linux/bitops.h>
	10	#include <linux/errno.h>
	11	#include <linux/init.h>
	12	#include <linux/kernel.h>
86bba269	13	#include <linux/workqueue.h>
1da177e4 LT	14	#include <linux/mm.h>
1da177e4 LT	15	#include <linux/module.h>
5a0e3ad6	16	#include <linux/slab.h>
1da177e4	17	#include <linux/netdevice.h>
1da177e4 LT	18	#include <linux/skbuff.h>
	19	#include <linux/string.h>
	20	#include <linux/types.h>
e9dc8653	21	#include <net/net_namespace.h>
2fc1b5dd	22	#include <linux/sched.h>
268bb0ce	23	#include <linux/prefetch.h>
61adedf3	24	#include <net/lwtunnel.h>
b6ca8bd5	25	#include <net/xfrm.h>
1da177e4 LT	26
1da177e4 LT	27	#include <net/dst.h>
f38a9eb1	28	#include <net/dst_metadata.h>
1da177e4	29
ede2059d	30	int dst_discard_out(struct net net, struct sock sk, struct sk_buff *skb)
1da177e4 LT	31	{
	32	kfree_skb(skb);
	33	return 0;
	34	}
ede2059d	35	EXPORT_SYMBOL(dst_discard_out);
1da177e4	36
3fb07daf	37	const struct dst_metrics dst_default_metrics = {
a37e6e34 ED	38	/* This initializer is needed to force linker to place this variable
	39	* into const section. Otherwise it might end into bss section.
	40	* We really want to avoid false sharing on this variable, and catch
	41	* any writes on it.
	42	*/
9620fef2	43	.refcnt = REFCOUNT_INIT(1),
a37e6e34	44	};
d4ead6b3	45	EXPORT_SYMBOL(dst_default_metrics);
a37e6e34	46
f38a9eb1	47	void dst_init(struct dst_entry dst, struct dst_ops ops,
762c8dc7	48	struct net_device *dev, int initial_obsolete,
f38a9eb1	49	unsigned short flags)
1da177e4	50	{
5c1e6aa3	51	dst->dev = dev;
d62607c3	52	netdev_hold(dev, &dst->dev_tracker, GFP_ATOMIC);
1da177e4	53	dst->ops = ops;
3fb07daf	54	dst_init_metrics(dst, dst_default_metrics.metrics, true);
cf911662	55	dst->expires = 0UL;
cf911662 DM	56	#ifdef CONFIG_XFRM
	57	dst->xfrm = NULL;
	58	#endif
5c1e6aa3	59	dst->input = dst_discard;
ede2059d	60	dst->output = dst_discard_out;
cf911662	61	dst->error = 0;
5c1e6aa3	62	dst->obsolete = initial_obsolete;
cf911662 DM	63	dst->header_len = 0;
	64	dst->trailer_len = 0;
	65	#ifdef CONFIG_IP_ROUTE_CLASSID
	66	dst->tclassid = 0;
1da177e4	67	#endif
61adedf3	68	dst->lwtstate = NULL;
762c8dc7	69	rcuref_init(&dst->__rcuref, 1);
418a7307	70	INIT_LIST_HEAD(&dst->rt_uncached);
cf911662	71	dst->__use = 0;
5c1e6aa3 DM	72	dst->lastuse = jiffies;
5c1e6aa3 DM	73	dst->flags = flags;
957c665f DM	74	if (!(flags & DST_NOCOUNT))
957c665f DM	75	dst_entries_add(ops, 1);
f38a9eb1 TG	76	}
	77	EXPORT_SYMBOL(dst_init);
	78
	79	void dst_alloc(struct dst_ops ops, struct net_device *dev,
762c8dc7	80	int initial_obsolete, unsigned short flags)
f38a9eb1 TG	81	{
	82	struct dst_entry *dst;
	83
cf86a086 ED	84	if (ops->gc &&
cf86a086 ED	85	!(flags & DST_NOCOUNT) &&
af6d1034 JM	86	dst_entries_get_fast(ops) > ops->gc_thresh)
af6d1034 JM	87	ops->gc(ops);
f38a9eb1 TG	88
	89	dst = kmem_cache_alloc(ops->kmem_cachep, GFP_ATOMIC);
	90	if (!dst)
	91	return NULL;
	92
762c8dc7	93	dst_init(dst, ops, dev, initial_obsolete, flags);
f38a9eb1	94
1da177e4 LT	95	return dst;
1da177e4 LT	96	}
598ed936	97	EXPORT_SYMBOL(dst_alloc);
1da177e4	98
1da177e4 LT	99	struct dst_entry dst_destroy(struct dst_entry dst)
1da177e4 LT	100	{
b92cf4aa	101	struct dst_entry *child = NULL;
1da177e4 LT	102
	103	smp_rmb();
	104
b92cf4aa	105	#ifdef CONFIG_XFRM
b6ca8bd5 DM	106	if (dst->xfrm) {
	107	struct xfrm_dst xdst = (struct xfrm_dst ) dst;
	108
	109	child = xdst->child;
	110	}
b92cf4aa	111	#endif
957c665f DM	112	if (!(dst->flags & DST_NOCOUNT))
957c665f DM	113	dst_entries_add(dst->ops, -1);
1da177e4 LT	114
	115	if (dst->ops->destroy)
	116	dst->ops->destroy(dst);
d62607c3	117	netdev_put(dst->dev, &dst->dev_tracker);
f38a9eb1	118
e252b3d1 WC	119	lwtstate_put(dst->lwtstate);
e252b3d1 WC	120
f38a9eb1	121	if (dst->flags & DST_METADATA)
d71785ff	122	metadata_dst_free((struct metadata_dst *)dst);
f38a9eb1 TG	123	else
f38a9eb1 TG	124	kmem_cache_free(dst->ops->kmem_cachep, dst);
1da177e4 LT	125
1da177e4 LT	126	dst = child;
52df157f WW	127	if (dst)
52df157f WW	128	dst_release_immediate(dst);
1da177e4 LT	129	return NULL;
1da177e4 LT	130	}
598ed936	131	EXPORT_SYMBOL(dst_destroy);
1da177e4	132
f8864972 ED	133	static void dst_destroy_rcu(struct rcu_head *head)
	134	{
	135	struct dst_entry *dst = container_of(head, struct dst_entry, rcu_head);
	136
	137	dst = dst_destroy(dst);
f8864972 ED	138	}
f8864972 ED	139
4a6ce2b6 WW	140	/* Operations to mark dst as DEAD and clean up the net device referenced
4a6ce2b6 WW	141	* by dst:
1be107de	142	* 1. put the dst under blackhole interface and discard all tx/rx packets
4a6ce2b6 WW	143	* on this route.
	144	* 2. release the net_device
	145	* This function should be called when removing routes from the fib tree
	146	* in preparation for a NETDEV_DOWN/NETDEV_UNREGISTER event and also to
	147	* make the next dst_ops->check() fail.
	148	*/
	149	void dst_dev_put(struct dst_entry *dst)
	150	{
	151	struct net_device *dev = dst->dev;
	152
	153	dst->obsolete = DST_OBSOLETE_DEAD;
	154	if (dst->ops->ifdown)
43c28172	155	dst->ops->ifdown(dst, dev);
4a6ce2b6 WW	156	dst->input = dst_discard;
4a6ce2b6 WW	157	dst->output = dst_discard_out;
8d7017fd	158	dst->dev = blackhole_netdev;
d62607c3 JK	159	netdev_ref_replace(dev, blackhole_netdev, &dst->dev_tracker,
d62607c3 JK	160	GFP_ATOMIC);
4a6ce2b6 WW	161	}
	162	EXPORT_SYMBOL(dst_dev_put);
	163
8d330868 IJ	164	void dst_release(struct dst_entry *dst)
8d330868 IJ	165	{
bc9d3a9f TG	166	if (dst && rcuref_put(&dst->__rcuref))
bc9d3a9f TG	167	call_rcu_hurry(&dst->rcu_head, dst_destroy_rcu);
8d330868 IJ	168	}
	169	EXPORT_SYMBOL(dst_release);
	170
5f56f409 WW	171	void dst_release_immediate(struct dst_entry *dst)
5f56f409 WW	172	{
bc9d3a9f TG	173	if (dst && rcuref_put(&dst->__rcuref))
bc9d3a9f TG	174	dst_destroy(dst);
5f56f409 WW	175	}
	176	EXPORT_SYMBOL(dst_release_immediate);
	177
62fa8a84 DM	178	u32 dst_cow_metrics_generic(struct dst_entry dst, unsigned long old)
62fa8a84 DM	179	{
3fb07daf	180	struct dst_metrics p = kmalloc(sizeof(p), GFP_ATOMIC);
62fa8a84 DM	181
62fa8a84 DM	182	if (p) {
3fb07daf	183	struct dst_metrics old_p = (struct dst_metrics )__DST_METRICS_PTR(old);
62fa8a84 DM	184	unsigned long prev, new;
62fa8a84 DM	185
9620fef2	186	refcount_set(&p->refcnt, 1);
3fb07daf	187	memcpy(p->metrics, old_p->metrics, sizeof(p->metrics));
62fa8a84 DM	188
	189	new = (unsigned long) p;
	190	prev = cmpxchg(&dst->_metrics, old, new);
	191
	192	if (prev != old) {
	193	kfree(p);
3fb07daf	194	p = (struct dst_metrics *)__DST_METRICS_PTR(prev);
62fa8a84 DM	195	if (prev & DST_METRICS_READ_ONLY)
62fa8a84 DM	196	p = NULL;
3fb07daf	197	} else if (prev & DST_METRICS_REFCOUNTED) {
9620fef2	198	if (refcount_dec_and_test(&old_p->refcnt))
3fb07daf	199	kfree(old_p);
62fa8a84 DM	200	}
62fa8a84 DM	201	}
3fb07daf ED	202	BUILD_BUG_ON(offsetof(struct dst_metrics, metrics) != 0);
3fb07daf ED	203	return (u32 *)p;
62fa8a84 DM	204	}
	205	EXPORT_SYMBOL(dst_cow_metrics_generic);
	206
	207	/* Caller asserts that dst_metrics_read_only(dst) is false. */
	208	void __dst_destroy_metrics_generic(struct dst_entry *dst, unsigned long old)
	209	{
	210	unsigned long prev, new;
	211
3fb07daf	212	new = ((unsigned long) &dst_default_metrics) \| DST_METRICS_READ_ONLY;
62fa8a84 DM	213	prev = cmpxchg(&dst->_metrics, old, new);
	214	if (prev == old)
	215	kfree(__DST_METRICS_PTR(old));
	216	}
	217	EXPORT_SYMBOL(__dst_destroy_metrics_generic);
	218
c4c877b2 DB	219	struct dst_entry dst_blackhole_check(struct dst_entry dst, u32 cookie)
	220	{
	221	return NULL;
	222	}
	223
	224	u32 dst_blackhole_cow_metrics(struct dst_entry dst, unsigned long old)
	225	{
	226	return NULL;
	227	}
	228
	229	struct neighbour dst_blackhole_neigh_lookup(const struct dst_entry dst,
	230	struct sk_buff *skb,
	231	const void *daddr)
	232	{
	233	return NULL;
	234	}
	235
	236	void dst_blackhole_update_pmtu(struct dst_entry dst, struct sock sk,
	237	struct sk_buff *skb, u32 mtu,
	238	bool confirm_neigh)
	239	{
	240	}
	241	EXPORT_SYMBOL_GPL(dst_blackhole_update_pmtu);
	242
	243	void dst_blackhole_redirect(struct dst_entry dst, struct sock sk,
	244	struct sk_buff *skb)
	245	{
	246	}
	247	EXPORT_SYMBOL_GPL(dst_blackhole_redirect);
	248
	249	unsigned int dst_blackhole_mtu(const struct dst_entry *dst)
	250	{
	251	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
	252
	253	return mtu ? : dst->dev->mtu;
	254	}
	255	EXPORT_SYMBOL_GPL(dst_blackhole_mtu);
	256
a188bb56 DB	257	static struct dst_ops dst_blackhole_ops = {
	258	.family = AF_UNSPEC,
	259	.neigh_lookup = dst_blackhole_neigh_lookup,
	260	.check = dst_blackhole_check,
	261	.cow_metrics = dst_blackhole_cow_metrics,
	262	.update_pmtu = dst_blackhole_update_pmtu,
	263	.redirect = dst_blackhole_redirect,
	264	.mtu = dst_blackhole_mtu,
f38a9eb1 TG	265	};
f38a9eb1 TG	266
3fcece12 JK	267	static void __metadata_dst_init(struct metadata_dst *md_dst,
3fcece12 JK	268	enum metadata_type type, u8 optslen)
f38a9eb1	269	{
f38a9eb1 TG	270	struct dst_entry *dst;
f38a9eb1 TG	271
f38a9eb1	272	dst = &md_dst->dst;
762c8dc7	273	dst_init(dst, &dst_blackhole_ops, NULL, DST_OBSOLETE_NONE,
a4c2fd7f	274	DST_METADATA \| DST_NOCOUNT);
f38a9eb1	275	memset(dst + 1, 0, sizeof(md_dst) + optslen - sizeof(dst));
3fcece12	276	md_dst->type = type;
d3aa45ce AS	277	}
d3aa45ce AS	278
3fcece12 JK	279	struct metadata_dst *metadata_dst_alloc(u8 optslen, enum metadata_type type,
3fcece12 JK	280	gfp_t flags)
d3aa45ce AS	281	{
	282	struct metadata_dst *md_dst;
	283
	284	md_dst = kmalloc(sizeof(*md_dst) + optslen, flags);
	285	if (!md_dst)
	286	return NULL;
	287
3fcece12	288	__metadata_dst_init(md_dst, type, optslen);
f38a9eb1 TG	289
	290	return md_dst;
	291	}
	292	EXPORT_SYMBOL_GPL(metadata_dst_alloc);
	293
d71785ff PA	294	void metadata_dst_free(struct metadata_dst *md_dst)
	295	{
	296	#ifdef CONFIG_DST_CACHE
e65a4955 DL	297	if (md_dst->type == METADATA_IP_TUNNEL)
e65a4955 DL	298	dst_cache_destroy(&md_dst->u.tun_info.dst_cache);
d71785ff	299	#endif
94151f5a EB	300	if (md_dst->type == METADATA_XFRM)
94151f5a EB	301	dst_release(md_dst->u.xfrm_info.dst_orig);
d71785ff PA	302	kfree(md_dst);
d71785ff PA	303	}
af308b94	304	EXPORT_SYMBOL_GPL(metadata_dst_free);
d71785ff	305
3fcece12 JK	306	struct metadata_dst __percpu *
3fcece12 JK	307	metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags)
d3aa45ce AS	308	{
	309	int cpu;
	310	struct metadata_dst __percpu *md_dst;
	311
	312	md_dst = __alloc_percpu_gfp(sizeof(struct metadata_dst) + optslen,
	313	__alignof__(struct metadata_dst), flags);
	314	if (!md_dst)
	315	return NULL;
	316
	317	for_each_possible_cpu(cpu)
3fcece12	318	__metadata_dst_init(per_cpu_ptr(md_dst, cpu), type, optslen);
d3aa45ce AS	319
	320	return md_dst;
	321	}
	322	EXPORT_SYMBOL_GPL(metadata_dst_alloc_percpu);
d66f2b91 JK	323
	324	void metadata_dst_free_percpu(struct metadata_dst __percpu *md_dst)
	325	{
	326	int cpu;
	327
d66f2b91 JK	328	for_each_possible_cpu(cpu) {
	329	struct metadata_dst *one_md_dst = per_cpu_ptr(md_dst, cpu);
	330
94151f5a	331	#ifdef CONFIG_DST_CACHE
d66f2b91 JK	332	if (one_md_dst->type == METADATA_IP_TUNNEL)
d66f2b91 JK	333	dst_cache_destroy(&one_md_dst->u.tun_info.dst_cache);
d66f2b91	334	#endif
94151f5a EB	335	if (one_md_dst->type == METADATA_XFRM)
	336	dst_release(one_md_dst->u.xfrm_info.dst_orig);
	337	}
d66f2b91 JK	338	free_percpu(md_dst);
	339	}
	340	EXPORT_SYMBOL_GPL(metadata_dst_free_percpu);