Commit 32637e33 authored by Toke Høiland-Jørgensen's avatar Toke Høiland-Jørgensen Committed by Alexei Starovoitov
Browse files

bpf: Expand map key argument of bpf_redirect_map to u64 



For queueing packets in XDP we want to add a new redirect map type with
support for 64-bit indexes. To prepare fore this, expand the width of the
'key' argument to the bpf_redirect_map() helper. Since BPF registers are
always 64-bit, this should be safe to do after the fact.

Acked-by: default avatarSong Liu <song@kernel.org>
Reviewed-by: default avatarStanislav Fomichev <sdf@google.com>
Signed-off-by: default avatarToke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20221108140601.149971-3-toke@redhat.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 14d898f3

include/linux/bpf.h

+1 −1
Original line number Diff line number Diff line
@@ -135,7 +135,7 @@ struct bpf_map_ops { 
	struct bpf_local_storage __rcu ** (*map_owner_storage_ptr)(void *owner);



	/* Misc helpers.*/

	int (*map_redirect)(struct bpf_map *map, u32 ifindex, u64 flags);

	int (*map_redirect)(struct bpf_map *map, u64 key, u64 flags);



	/* map_meta_equal must be implemented for maps that can be

	 * used as an inner map.  It is a runtime check to ensure

include/linux/filter.h

+6 −6
Original line number Diff line number Diff line
@@ -643,13 +643,13 @@ struct bpf_nh_params { 
};



struct bpf_redirect_info {

	u32 flags;

	u32 tgt_index;

	u64 tgt_index;

	void *tgt_value;

	struct bpf_map *map;

	u32 flags;

	u32 kern_flags;

	u32 map_id;

	enum bpf_map_type map_type;

	u32 kern_flags;

	struct bpf_nh_params nh;

};
@@ -1504,7 +1504,7 @@ static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol, 
}

#endif /* IS_ENABLED(CONFIG_IPV6) */



static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex,

static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u64 index,

						  u64 flags, const u64 flag_mask,

						  void *lookup_elem(struct bpf_map *map, u32 key))

{
@@ -1515,7 +1515,7 @@ static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifind 
	if (unlikely(flags & ~(action_mask | flag_mask)))

		return XDP_ABORTED;



	ri->tgt_value = lookup_elem(map, ifindex);

	ri->tgt_value = lookup_elem(map, index);

	if (unlikely(!ri->tgt_value) && !(flags & BPF_F_BROADCAST)) {

		/* If the lookup fails we want to clear out the state in the

		 * redirect_info struct completely, so that if an eBPF program
@@ -1527,7 +1527,7 @@ static __always_inline int __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifind 
		return flags & action_mask;

	}



	ri->tgt_index = ifindex;

	ri->tgt_index = index;

	ri->map_id = map->id;

	ri->map_type = map->map_type;

include/uapi/linux/bpf.h

+1 −1
Original line number Diff line number Diff line
@@ -2647,7 +2647,7 @@ union bpf_attr { 
 * 	Return

 * 		0 on success, or a negative error in case of failure.

 *

 * long bpf_redirect_map(struct bpf_map *map, u32 key, u64 flags)

 * long bpf_redirect_map(struct bpf_map *map, u64 key, u64 flags)

 * 	Description

 * 		Redirect the packet to the endpoint referenced by *map* at

 * 		index *key*. Depending on its type, this *map* can contain

kernel/bpf/cpumap.c

+2 −2
Original line number Diff line number Diff line
@@ -667,9 +667,9 @@ static int cpu_map_get_next_key(struct bpf_map *map, void *key, void *next_key) 
	return 0;

}



static int cpu_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags)

static int cpu_map_redirect(struct bpf_map *map, u64 index, u64 flags)

{

	return __bpf_xdp_redirect_map(map, ifindex, flags, 0,

	return __bpf_xdp_redirect_map(map, index, flags, 0,

				      __cpu_map_lookup_elem);

}

kernel/bpf/devmap.c

+2 −2
Original line number Diff line number Diff line
@@ -992,14 +992,14 @@ static int dev_map_hash_update_elem(struct bpf_map *map, void *key, void *value, 
					 map, key, value, map_flags);

}



static int dev_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags)

static int dev_map_redirect(struct bpf_map *map, u64 ifindex, u64 flags)

{

	return __bpf_xdp_redirect_map(map, ifindex, flags,

				      BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS,

				      __dev_map_lookup_elem);

}



static int dev_hash_map_redirect(struct bpf_map *map, u32 ifindex, u64 flags)

static int dev_hash_map_redirect(struct bpf_map *map, u64 ifindex, u64 flags)

{

	return __bpf_xdp_redirect_map(map, ifindex, flags,

				      BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS,