[linux-block.git] / include / net / nexthop.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Generic nexthop implementation
 *
 * Copyright (c) 2017-19 Cumulus Networks
 * Copyright (c) 2017-19 David Ahern <dsa@cumulusnetworks.com>
 */

#ifndef __LINUX_NEXTHOP_H
#define __LINUX_NEXTHOP_H

#include <linux/netdevice.h>
#include <linux/notifier.h>
#include <linux/route.h>
#include <linux/types.h>
#include <net/ip_fib.h>
#include <net/ip6_fib.h>
#include <net/netlink.h>

#define NEXTHOP_VALID_USER_FLAGS RTNH_F_ONLINK

struct nexthop;

struct nh_config {
	u32		nh_id;

	u8		nh_family;
	u8		nh_protocol;
	u8		nh_blackhole;
	u8		nh_fdb;
	u32		nh_flags;

	int		nh_ifindex;
	struct net_device *dev;

	union {
		__be32		ipv4;
		struct in6_addr	ipv6;
	} gw;

	struct nlattr	*nh_grp;
	u16		nh_grp_type;

	struct nlattr	*nh_encap;
	u16		nh_encap_type;

	u32		nlflags;
	struct nl_info	nlinfo;
};

struct nh_info {
	struct hlist_node	dev_hash;    /* entry on netns devhash */
	struct nexthop		*nh_parent;

	u8			family;
	bool			reject_nh;
	bool			fdb_nh;

	union {
		struct fib_nh_common	fib_nhc;
		struct fib_nh		fib_nh;
		struct fib6_nh		fib6_nh;
	};
};

struct nh_grp_entry {
	struct nexthop	*nh;
	u8		weight;

	union {
		struct {
			atomic_t	upper_bound;
		} mpath;
	};

	struct list_head nh_list;
	struct nexthop	*nh_parent;  /* nexthop of group with this entry */
};

struct nh_group {
	struct nh_group		*spare; /* spare group for removals */
	u16			num_nh;
	bool			mpath;
	bool			fdb_nh;
	bool			has_v4;
	struct nh_grp_entry	nh_entries[];
};

struct nexthop {
	struct rb_node		rb_node;    /* entry on netns rbtree */
	struct list_head	fi_list;    /* v4 entries using nh */
	struct list_head	f6i_list;   /* v6 entries using nh */
	struct list_head        fdb_list;   /* fdb entries using this nh */
	struct list_head	grp_list;   /* nh group entries using this nh */
	struct net		*net;

	u32			id;

	u8			protocol;   /* app managing this nh */
	u8			nh_flags;
	bool			is_group;

	refcount_t		refcnt;
	struct rcu_head		rcu;

	union {
		struct nh_info	__rcu *nh_info;
		struct nh_group __rcu *nh_grp;
	};
};

enum nexthop_event_type {
	NEXTHOP_EVENT_DEL,
	NEXTHOP_EVENT_REPLACE,
};

enum nh_notifier_info_type {
	NH_NOTIFIER_INFO_TYPE_SINGLE,
	NH_NOTIFIER_INFO_TYPE_GRP,
};

struct nh_notifier_single_info {
	struct net_device *dev;
	u8 gw_family;
	union {
		__be32 ipv4;
		struct in6_addr ipv6;
	};
	u8 is_reject:1,
	   is_fdb:1,
	   has_encap:1;
};

struct nh_notifier_grp_entry_info {
	u8 weight;
	u32 id;
	struct nh_notifier_single_info nh;
};

struct nh_notifier_grp_info {
	u16 num_nh;
	bool is_fdb;
	struct nh_notifier_grp_entry_info nh_entries[];
};

struct nh_notifier_info {
	struct net *net;
	struct netlink_ext_ack *extack;
	u32 id;
	enum nh_notifier_info_type type;
	union {
		struct nh_notifier_single_info *nh;
		struct nh_notifier_grp_info *nh_grp;
	};
};

int register_nexthop_notifier(struct net *net, struct notifier_block *nb,
			      struct netlink_ext_ack *extack);
int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb);
void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap);

/* caller is holding rcu or rtnl; no reference taken to nexthop */
struct nexthop *nexthop_find_by_id(struct net *net, u32 id);
void nexthop_free_rcu(struct rcu_head *head);

static inline bool nexthop_get(struct nexthop *nh)
{
	return refcount_inc_not_zero(&nh->refcnt);
}

static inline void nexthop_put(struct nexthop *nh)
{
	if (refcount_dec_and_test(&nh->refcnt))
		call_rcu(&nh->rcu, nexthop_free_rcu);
}

static inline bool nexthop_cmp(const struct nexthop *nh1,
			       const struct nexthop *nh2)
{
	return nh1 == nh2;
}

static inline bool nexthop_is_fdb(const struct nexthop *nh)
{
	if (nh->is_group) {
		const struct nh_group *nh_grp;

		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
		return nh_grp->fdb_nh;
	} else {
		const struct nh_info *nhi;

		nhi = rcu_dereference_rtnl(nh->nh_info);
		return nhi->fdb_nh;
	}
}

static inline bool nexthop_has_v4(const struct nexthop *nh)
{
	if (nh->is_group) {
		struct nh_group *nh_grp;

		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
		return nh_grp->has_v4;
	}
	return false;
}

static inline bool nexthop_is_multipath(const struct nexthop *nh)
{
	if (nh->is_group) {
		struct nh_group *nh_grp;

		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
		return nh_grp->mpath;
	}
	return false;
}

struct nexthop *nexthop_select_path(struct nexthop *nh, int hash);

static inline unsigned int nexthop_num_path(const struct nexthop *nh)
{
	unsigned int rc = 1;

	if (nh->is_group) {
		struct nh_group *nh_grp;

		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
		if (nh_grp->mpath)
			rc = nh_grp->num_nh;
	}

	return rc;
}

static inline
struct nexthop *nexthop_mpath_select(const struct nh_group *nhg, int nhsel)
{
	/* for_nexthops macros in fib_semantics.c grabs a pointer to
	 * the nexthop before checking nhsel
	 */
	if (nhsel >= nhg->num_nh)
		return NULL;

	return nhg->nh_entries[nhsel].nh;
}

static inline
int nexthop_mpath_fill_node(struct sk_buff *skb, struct nexthop *nh,
			    u8 rt_family)
{
	struct nh_group *nhg = rtnl_dereference(nh->nh_grp);
	int i;

	for (i = 0; i < nhg->num_nh; i++) {
		struct nexthop *nhe = nhg->nh_entries[i].nh;
		struct nh_info *nhi = rcu_dereference_rtnl(nhe->nh_info);
		struct fib_nh_common *nhc = &nhi->fib_nhc;
		int weight = nhg->nh_entries[i].weight;

		if (fib_add_nexthop(skb, nhc, weight, rt_family) < 0)
			return -EMSGSIZE;
	}

	return 0;
}

/* called with rcu lock */
static inline bool nexthop_is_blackhole(const struct nexthop *nh)
{
	const struct nh_info *nhi;

	if (nh->is_group) {
		struct nh_group *nh_grp;

		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
		if (nh_grp->num_nh > 1)
			return false;

		nh = nh_grp->nh_entries[0].nh;
	}

	nhi = rcu_dereference_rtnl(nh->nh_info);
	return nhi->reject_nh;
}

static inline void nexthop_path_fib_result(struct fib_result *res, int hash)
{
	struct nh_info *nhi;
	struct nexthop *nh;

	nh = nexthop_select_path(res->fi->nh, hash);
	nhi = rcu_dereference(nh->nh_info);
	res->nhc = &nhi->fib_nhc;
}

/* called with rcu read lock or rtnl held */
static inline
struct fib_nh_common *nexthop_fib_nhc(struct nexthop *nh, int nhsel)
{
	struct nh_info *nhi;

	BUILD_BUG_ON(offsetof(struct fib_nh, nh_common) != 0);
	BUILD_BUG_ON(offsetof(struct fib6_nh, nh_common) != 0);

	if (nh->is_group) {
		struct nh_group *nh_grp;

		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
		if (nh_grp->mpath) {
			nh = nexthop_mpath_select(nh_grp, nhsel);
			if (!nh)
				return NULL;
		}
	}

	nhi = rcu_dereference_rtnl(nh->nh_info);
	return &nhi->fib_nhc;
}

/* called from fib_table_lookup with rcu_lock */
static inline
struct fib_nh_common *nexthop_get_nhc_lookup(const struct nexthop *nh,
					     int fib_flags,
					     const struct flowi4 *flp,
					     int *nhsel)
{
	struct nh_info *nhi;

	if (nh->is_group) {
		struct nh_group *nhg = rcu_dereference(nh->nh_grp);
		int i;

		for (i = 0; i < nhg->num_nh; i++) {
			struct nexthop *nhe = nhg->nh_entries[i].nh;

			nhi = rcu_dereference(nhe->nh_info);
			if (fib_lookup_good_nhc(&nhi->fib_nhc, fib_flags, flp)) {
				*nhsel = i;
				return &nhi->fib_nhc;
			}
		}
	} else {
		nhi = rcu_dereference(nh->nh_info);
		if (fib_lookup_good_nhc(&nhi->fib_nhc, fib_flags, flp)) {
			*nhsel = 0;
			return &nhi->fib_nhc;
		}
	}

	return NULL;
}

static inline bool nexthop_uses_dev(const struct nexthop *nh,
				    const struct net_device *dev)
{
	struct nh_info *nhi;

	if (nh->is_group) {
		struct nh_group *nhg = rcu_dereference(nh->nh_grp);
		int i;

		for (i = 0; i < nhg->num_nh; i++) {
			struct nexthop *nhe = nhg->nh_entries[i].nh;

			nhi = rcu_dereference(nhe->nh_info);
			if (nhc_l3mdev_matches_dev(&nhi->fib_nhc, dev))
				return true;
		}
	} else {
		nhi = rcu_dereference(nh->nh_info);
		if (nhc_l3mdev_matches_dev(&nhi->fib_nhc, dev))
			return true;
	}

	return false;
}

static inline unsigned int fib_info_num_path(const struct fib_info *fi)
{
	if (unlikely(fi->nh))
		return nexthop_num_path(fi->nh);

	return fi->fib_nhs;
}

int fib_check_nexthop(struct nexthop *nh, u8 scope,
		      struct netlink_ext_ack *extack);

static inline struct fib_nh_common *fib_info_nhc(struct fib_info *fi, int nhsel)
{
	if (unlikely(fi->nh))
		return nexthop_fib_nhc(fi->nh, nhsel);

	return &fi->fib_nh[nhsel].nh_common;
}

/* only used when fib_nh is built into fib_info */
static inline struct fib_nh *fib_info_nh(struct fib_info *fi, int nhsel)
{
	WARN_ON(fi->nh);

	return &fi->fib_nh[nhsel];
}

/*
 * IPv6 variants
 */
int fib6_check_nexthop(struct nexthop *nh, struct fib6_config *cfg,
		       struct netlink_ext_ack *extack);

static inline struct fib6_nh *nexthop_fib6_nh(struct nexthop *nh)
{
	struct nh_info *nhi;

	if (nh->is_group) {
		struct nh_group *nh_grp;

		nh_grp = rcu_dereference_rtnl(nh->nh_grp);
		nh = nexthop_mpath_select(nh_grp, 0);
		if (!nh)
			return NULL;
	}

	nhi = rcu_dereference_rtnl(nh->nh_info);
	if (nhi->family == AF_INET6)
		return &nhi->fib6_nh;

	return NULL;
}

static inline struct net_device *fib6_info_nh_dev(struct fib6_info *f6i)
{
	struct fib6_nh *fib6_nh;

	fib6_nh = f6i->nh ? nexthop_fib6_nh(f6i->nh) : f6i->fib6_nh;
	return fib6_nh->fib_nh_dev;
}

static inline void nexthop_path_fib6_result(struct fib6_result *res, int hash)
{
	struct nexthop *nh = res->f6i->nh;
	struct nh_info *nhi;

	nh = nexthop_select_path(nh, hash);

	nhi = rcu_dereference_rtnl(nh->nh_info);
	if (nhi->reject_nh) {
		res->fib6_type = RTN_BLACKHOLE;
		res->fib6_flags |= RTF_REJECT;
		res->nh = nexthop_fib6_nh(nh);
	} else {
		res->nh = &nhi->fib6_nh;
	}
}

int nexthop_for_each_fib6_nh(struct nexthop *nh,
			     int (*cb)(struct fib6_nh *nh, void *arg),
			     void *arg);

static inline int nexthop_get_family(struct nexthop *nh)
{
	struct nh_info *nhi = rcu_dereference_rtnl(nh->nh_info);

	return nhi->family;
}

static inline
struct fib_nh_common *nexthop_fdb_nhc(struct nexthop *nh)
{
	struct nh_info *nhi = rcu_dereference_rtnl(nh->nh_info);

	return &nhi->fib_nhc;
}

static inline struct fib_nh_common *nexthop_path_fdb_result(struct nexthop *nh,
							    int hash)
{
	struct nh_info *nhi;
	struct nexthop *nhp;

	nhp = nexthop_select_path(nh, hash);
	if (unlikely(!nhp))
		return NULL;
	nhi = rcu_dereference(nhp->nh_info);
	return &nhi->fib_nhc;
}
#endif
Commit	Line	Data
ab84be7e DA	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	/*
	3	* Generic nexthop implementation
	4	*
	5	* Copyright (c) 2017-19 Cumulus Networks
	6	* Copyright (c) 2017-19 David Ahern <dsa@cumulusnetworks.com>
	7	*/
	8
	9	#ifndef __LINUX_NEXTHOP_H
	10	#define __LINUX_NEXTHOP_H
	11
	12	#include <linux/netdevice.h>
8590ceed	13	#include <linux/notifier.h>
f88d8ea6	14	#include <linux/route.h>
ab84be7e DA	15	#include <linux/types.h>
ab84be7e DA	16	#include <net/ip_fib.h>
53010f99	17	#include <net/ip6_fib.h>
ab84be7e DA	18	#include <net/netlink.h>
	19
	20	#define NEXTHOP_VALID_USER_FLAGS RTNH_F_ONLINK
	21
	22	struct nexthop;
	23
	24	struct nh_config {
	25	u32 nh_id;
	26
	27	u8 nh_family;
	28	u8 nh_protocol;
	29	u8 nh_blackhole;
38428d68	30	u8 nh_fdb;
ab84be7e DA	31	u32 nh_flags;
	32
	33	int nh_ifindex;
	34	struct net_device *dev;
	35
597cfe4f DA	36	union {
597cfe4f DA	37	__be32 ipv4;
53010f99	38	struct in6_addr ipv6;
597cfe4f DA	39	} gw;
597cfe4f DA	40
430a0491 DA	41	struct nlattr *nh_grp;
	42	u16 nh_grp_type;
	43
b513bd03 DA	44	struct nlattr *nh_encap;
	45	u16 nh_encap_type;
	46
ab84be7e DA	47	u32 nlflags;
	48	struct nl_info nlinfo;
	49	};
	50
	51	struct nh_info {
	52	struct hlist_node dev_hash; /* entry on netns devhash */
	53	struct nexthop *nh_parent;
	54
	55	u8 family;
	56	bool reject_nh;
38428d68	57	bool fdb_nh;
ab84be7e DA	58
	59	union {
	60	struct fib_nh_common fib_nhc;
597cfe4f	61	struct fib_nh fib_nh;
53010f99	62	struct fib6_nh fib6_nh;
ab84be7e DA	63	};
	64	};
	65
430a0491 DA	66	struct nh_grp_entry {
	67	struct nexthop *nh;
	68	u8 weight;
b9bae61b PM	69
	70	union {
	71	struct {
	72	atomic_t upper_bound;
	73	} mpath;
	74	};
430a0491 DA	75
	76	struct list_head nh_list;
	77	struct nexthop nh_parent; / nexthop of group with this entry */
	78	};
	79
	80	struct nh_group {
90f33bff	81	struct nh_group spare; / spare group for removals */
430a0491 DA	82	u16 num_nh;
430a0491 DA	83	bool mpath;
ce9ac056	84	bool fdb_nh;
430a0491	85	bool has_v4;
97a888c2	86	struct nh_grp_entry nh_entries[];
430a0491 DA	87	};
430a0491 DA	88
ab84be7e DA	89	struct nexthop {
ab84be7e DA	90	struct rb_node rb_node; /* entry on netns rbtree */
4c7e8084	91	struct list_head fi_list; /* v4 entries using nh */
f88d8ea6	92	struct list_head f6i_list; /* v6 entries using nh */
38428d68	93	struct list_head fdb_list; /* fdb entries using this nh */
430a0491	94	struct list_head grp_list; /* nh group entries using this nh */
ab84be7e DA	95	struct net *net;
	96
	97	u32 id;
	98
	99	u8 protocol; /* app managing this nh */
	100	u8 nh_flags;
430a0491	101	bool is_group;
ab84be7e DA	102
	103	refcount_t refcnt;
	104	struct rcu_head rcu;
	105
	106	union {
	107	struct nh_info __rcu *nh_info;
430a0491	108	struct nh_group __rcu *nh_grp;
ab84be7e DA	109	};
	110	};
	111
8590ceed	112	enum nexthop_event_type {
732d167b IS	113	NEXTHOP_EVENT_DEL,
732d167b IS	114	NEXTHOP_EVENT_REPLACE,
8590ceed RP	115	};
8590ceed RP	116
09ad6bec IS	117	enum nh_notifier_info_type {
	118	NH_NOTIFIER_INFO_TYPE_SINGLE,
	119	NH_NOTIFIER_INFO_TYPE_GRP,
	120	};
	121
1c9cac65 IS	122	struct nh_notifier_single_info {
	123	struct net_device *dev;
	124	u8 gw_family;
	125	union {
	126	__be32 ipv4;
	127	struct in6_addr ipv6;
	128	};
	129	u8 is_reject:1,
	130	is_fdb:1,
	131	has_encap:1;
	132	};
	133
	134	struct nh_notifier_grp_entry_info {
	135	u8 weight;
	136	u32 id;
	137	struct nh_notifier_single_info nh;
	138	};
	139
	140	struct nh_notifier_grp_info {
	141	u16 num_nh;
	142	bool is_fdb;
	143	struct nh_notifier_grp_entry_info nh_entries[];
	144	};
	145
	146	struct nh_notifier_info {
	147	struct net *net;
	148	struct netlink_ext_ack *extack;
	149	u32 id;
09ad6bec	150	enum nh_notifier_info_type type;
1c9cac65 IS	151	union {
	152	struct nh_notifier_single_info *nh;
	153	struct nh_notifier_grp_info *nh_grp;
	154	};
	155	};
	156
ce7e9c8a IS	157	int register_nexthop_notifier(struct net net, struct notifier_block nb,
ce7e9c8a IS	158	struct netlink_ext_ack *extack);
8590ceed	159	int unregister_nexthop_notifier(struct net net, struct notifier_block nb);
e95f2592	160	void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap);
8590ceed	161
ab84be7e DA	162	/* caller is holding rcu or rtnl; no reference taken to nexthop */
	163	struct nexthop nexthop_find_by_id(struct net net, u32 id);
	164	void nexthop_free_rcu(struct rcu_head *head);
	165
	166	static inline bool nexthop_get(struct nexthop *nh)
	167	{
	168	return refcount_inc_not_zero(&nh->refcnt);
	169	}
	170
	171	static inline void nexthop_put(struct nexthop *nh)
	172	{
	173	if (refcount_dec_and_test(&nh->refcnt))
	174	call_rcu(&nh->rcu, nexthop_free_rcu);
	175	}
	176
4c7e8084 DA	177	static inline bool nexthop_cmp(const struct nexthop *nh1,
	178	const struct nexthop *nh2)
	179	{
	180	return nh1 == nh2;
ce9ac056 DA	181	}
	182
	183	static inline bool nexthop_is_fdb(const struct nexthop *nh)
	184	{
	185	if (nh->is_group) {
	186	const struct nh_group *nh_grp;
	187
	188	nh_grp = rcu_dereference_rtnl(nh->nh_grp);
	189	return nh_grp->fdb_nh;
	190	} else {
	191	const struct nh_info *nhi;
	192
	193	nhi = rcu_dereference_rtnl(nh->nh_info);
	194	return nhi->fdb_nh;
	195	}
50cb8769 DA	196	}
	197
	198	static inline bool nexthop_has_v4(const struct nexthop *nh)
	199	{
	200	if (nh->is_group) {
	201	struct nh_group *nh_grp;
	202
	203	nh_grp = rcu_dereference_rtnl(nh->nh_grp);
	204	return nh_grp->has_v4;
	205	}
	206	return false;
4c7e8084 DA	207	}
4c7e8084 DA	208
430a0491 DA	209	static inline bool nexthop_is_multipath(const struct nexthop *nh)
	210	{
	211	if (nh->is_group) {
	212	struct nh_group *nh_grp;
	213
	214	nh_grp = rcu_dereference_rtnl(nh->nh_grp);
	215	return nh_grp->mpath;
	216	}
	217	return false;
	218	}
	219
	220	struct nexthop nexthop_select_path(struct nexthop nh, int hash);
	221
	222	static inline unsigned int nexthop_num_path(const struct nexthop *nh)
	223	{
	224	unsigned int rc = 1;
	225
0b5e2e39	226	if (nh->is_group) {
430a0491 DA	227	struct nh_group *nh_grp;
	228
	229	nh_grp = rcu_dereference_rtnl(nh->nh_grp);
0b5e2e39 DA	230	if (nh_grp->mpath)
0b5e2e39 DA	231	rc = nh_grp->num_nh;
430a0491 DA	232	}
	233
	234	return rc;
	235	}
	236
	237	static inline
0b5e2e39	238	struct nexthop nexthop_mpath_select(const struct nh_group nhg, int nhsel)
430a0491	239	{
430a0491 DA	240	/* for_nexthops macros in fib_semantics.c grabs a pointer to
	241	* the nexthop before checking nhsel
	242	*/
5270041d	243	if (nhsel >= nhg->num_nh)
430a0491 DA	244	return NULL;
	245
	246	return nhg->nh_entries[nhsel].nh;
	247	}
	248
	249	static inline
7bdf4de1 DS	250	int nexthop_mpath_fill_node(struct sk_buff skb, struct nexthop nh,
7bdf4de1 DS	251	u8 rt_family)
430a0491 DA	252	{
	253	struct nh_group *nhg = rtnl_dereference(nh->nh_grp);
	254	int i;
	255
	256	for (i = 0; i < nhg->num_nh; i++) {
	257	struct nexthop *nhe = nhg->nh_entries[i].nh;
	258	struct nh_info *nhi = rcu_dereference_rtnl(nhe->nh_info);
	259	struct fib_nh_common *nhc = &nhi->fib_nhc;
	260	int weight = nhg->nh_entries[i].weight;
	261
7bdf4de1	262	if (fib_add_nexthop(skb, nhc, weight, rt_family) < 0)
430a0491 DA	263	return -EMSGSIZE;
	264	}
	265
	266	return 0;
	267	}
	268
ab84be7e DA	269	/* called with rcu lock */
	270	static inline bool nexthop_is_blackhole(const struct nexthop *nh)
	271	{
	272	const struct nh_info *nhi;
	273
0b5e2e39 DA	274	if (nh->is_group) {
	275	struct nh_group *nh_grp;
	276
	277	nh_grp = rcu_dereference_rtnl(nh->nh_grp);
	278	if (nh_grp->num_nh > 1)
430a0491	279	return false;
0b5e2e39 DA	280
0b5e2e39 DA	281	nh = nh_grp->nh_entries[0].nh;
430a0491 DA	282	}
	283
	284	nhi = rcu_dereference_rtnl(nh->nh_info);
ab84be7e DA	285	return nhi->reject_nh;
ab84be7e DA	286	}
5481d73f	287
4c7e8084 DA	288	static inline void nexthop_path_fib_result(struct fib_result *res, int hash)
	289	{
	290	struct nh_info *nhi;
	291	struct nexthop *nh;
	292
	293	nh = nexthop_select_path(res->fi->nh, hash);
	294	nhi = rcu_dereference(nh->nh_info);
	295	res->nhc = &nhi->fib_nhc;
	296	}
	297
	298	/* called with rcu read lock or rtnl held */
	299	static inline
	300	struct fib_nh_common nexthop_fib_nhc(struct nexthop nh, int nhsel)
	301	{
	302	struct nh_info *nhi;
	303
	304	BUILD_BUG_ON(offsetof(struct fib_nh, nh_common) != 0);
	305	BUILD_BUG_ON(offsetof(struct fib6_nh, nh_common) != 0);
	306
0b5e2e39 DA	307	if (nh->is_group) {
	308	struct nh_group *nh_grp;
	309
	310	nh_grp = rcu_dereference_rtnl(nh->nh_grp);
	311	if (nh_grp->mpath) {
	312	nh = nexthop_mpath_select(nh_grp, nhsel);
	313	if (!nh)
	314	return NULL;
	315	}
4c7e8084 DA	316	}
	317
	318	nhi = rcu_dereference_rtnl(nh->nh_info);
	319	return &nhi->fib_nhc;
	320	}
	321
af7888ad DA	322	/* called from fib_table_lookup with rcu_lock */
	323	static inline
	324	struct fib_nh_common nexthop_get_nhc_lookup(const struct nexthop nh,
	325	int fib_flags,
	326	const struct flowi4 *flp,
	327	int *nhsel)
	328	{
	329	struct nh_info *nhi;
	330
	331	if (nh->is_group) {
	332	struct nh_group *nhg = rcu_dereference(nh->nh_grp);
	333	int i;
	334
	335	for (i = 0; i < nhg->num_nh; i++) {
	336	struct nexthop *nhe = nhg->nh_entries[i].nh;
	337
	338	nhi = rcu_dereference(nhe->nh_info);
	339	if (fib_lookup_good_nhc(&nhi->fib_nhc, fib_flags, flp)) {
	340	*nhsel = i;
	341	return &nhi->fib_nhc;
	342	}
	343	}
	344	} else {
	345	nhi = rcu_dereference(nh->nh_info);
	346	if (fib_lookup_good_nhc(&nhi->fib_nhc, fib_flags, flp)) {
	347	*nhsel = 0;
	348	return &nhi->fib_nhc;
	349	}
	350	}
	351
	352	return NULL;
	353	}
	354
1fd1c768 DA	355	static inline bool nexthop_uses_dev(const struct nexthop *nh,
	356	const struct net_device *dev)
	357	{
	358	struct nh_info *nhi;
	359
	360	if (nh->is_group) {
	361	struct nh_group *nhg = rcu_dereference(nh->nh_grp);
	362	int i;
	363
	364	for (i = 0; i < nhg->num_nh; i++) {
	365	struct nexthop *nhe = nhg->nh_entries[i].nh;
	366
	367	nhi = rcu_dereference(nhe->nh_info);
	368	if (nhc_l3mdev_matches_dev(&nhi->fib_nhc, dev))
	369	return true;
	370	}
	371	} else {
	372	nhi = rcu_dereference(nh->nh_info);
	373	if (nhc_l3mdev_matches_dev(&nhi->fib_nhc, dev))
	374	return true;
	375	}
	376
	377	return false;
	378	}
	379
5481d73f DA	380	static inline unsigned int fib_info_num_path(const struct fib_info *fi)
5481d73f DA	381	{
4c7e8084 DA	382	if (unlikely(fi->nh))
	383	return nexthop_num_path(fi->nh);
	384
5481d73f DA	385	return fi->fib_nhs;
	386	}
	387
4c7e8084 DA	388	int fib_check_nexthop(struct nexthop *nh, u8 scope,
	389	struct netlink_ext_ack *extack);
	390
5481d73f DA	391	static inline struct fib_nh_common fib_info_nhc(struct fib_info fi, int nhsel)
5481d73f DA	392	{
4c7e8084 DA	393	if (unlikely(fi->nh))
	394	return nexthop_fib_nhc(fi->nh, nhsel);
	395
5481d73f DA	396	return &fi->fib_nh[nhsel].nh_common;
	397	}
	398
4c7e8084	399	/* only used when fib_nh is built into fib_info */
5481d73f DA	400	static inline struct fib_nh fib_info_nh(struct fib_info fi, int nhsel)
5481d73f DA	401	{
4c7e8084 DA	402	WARN_ON(fi->nh);
4c7e8084 DA	403
5481d73f DA	404	return &fi->fib_nh[nhsel];
5481d73f DA	405	}
f88d8ea6 DA	406
	407	/*
	408	* IPv6 variants
	409	*/
	410	int fib6_check_nexthop(struct nexthop nh, struct fib6_config cfg,
	411	struct netlink_ext_ack *extack);
	412
	413	static inline struct fib6_nh nexthop_fib6_nh(struct nexthop nh)
	414	{
	415	struct nh_info *nhi;
	416
0b5e2e39 DA	417	if (nh->is_group) {
	418	struct nh_group *nh_grp;
	419
	420	nh_grp = rcu_dereference_rtnl(nh->nh_grp);
	421	nh = nexthop_mpath_select(nh_grp, 0);
f88d8ea6 DA	422	if (!nh)
	423	return NULL;
	424	}
	425
	426	nhi = rcu_dereference_rtnl(nh->nh_info);
	427	if (nhi->family == AF_INET6)
	428	return &nhi->fib6_nh;
	429
	430	return NULL;
	431	}
	432
	433	static inline struct net_device fib6_info_nh_dev(struct fib6_info f6i)
	434	{
	435	struct fib6_nh *fib6_nh;
	436
	437	fib6_nh = f6i->nh ? nexthop_fib6_nh(f6i->nh) : f6i->fib6_nh;
	438	return fib6_nh->fib_nh_dev;
	439	}
	440
	441	static inline void nexthop_path_fib6_result(struct fib6_result *res, int hash)
	442	{
	443	struct nexthop *nh = res->f6i->nh;
	444	struct nh_info *nhi;
	445
	446	nh = nexthop_select_path(nh, hash);
	447
	448	nhi = rcu_dereference_rtnl(nh->nh_info);
	449	if (nhi->reject_nh) {
	450	res->fib6_type = RTN_BLACKHOLE;
	451	res->fib6_flags \|= RTF_REJECT;
	452	res->nh = nexthop_fib6_nh(nh);
	453	} else {
	454	res->nh = &nhi->fib6_nh;
	455	}
	456	}
f88c9aa1 DA	457
	458	int nexthop_for_each_fib6_nh(struct nexthop *nh,
	459	int (cb)(struct fib6_nh nh, void *arg),
	460	void *arg);
38428d68 RP	461
	462	static inline int nexthop_get_family(struct nexthop *nh)
	463	{
	464	struct nh_info *nhi = rcu_dereference_rtnl(nh->nh_info);
	465
	466	return nhi->family;
	467	}
	468
	469	static inline
	470	struct fib_nh_common nexthop_fdb_nhc(struct nexthop nh)
	471	{
	472	struct nh_info *nhi = rcu_dereference_rtnl(nh->nh_info);
	473
	474	return &nhi->fib_nhc;
	475	}
	476
	477	static inline struct fib_nh_common nexthop_path_fdb_result(struct nexthop nh,
	478	int hash)
	479	{
	480	struct nh_info *nhi;
	481	struct nexthop *nhp;
	482
	483	nhp = nexthop_select_path(nh, hash);
	484	if (unlikely(!nhp))
	485	return NULL;
	486	nhi = rcu_dereference(nhp->nh_info);
	487	return &nhi->fib_nhc;
	488	}
ab84be7e	489	#endif