[bpf-next,v4,1/2] bpf, xdp: make bpf_redirect_map() a map operation

Message ID	20210226112322.144927-2-bjorn.topel@gmail.com (mailing list archive)
State	Superseded
Delegated to:	BPF
Headers	show Return-Path: <bpf-owner@kernel.org> From: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= <bjorn.topel@gmail.com> To: ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, bpf@vger.kernel.org Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= <bjorn.topel@intel.com>, maciej.fijalkowski@intel.com, hawk@kernel.org, toke@redhat.com, magnus.karlsson@intel.com, john.fastabend@gmail.com, kuba@kernel.org, davem@davemloft.net Subject: [PATCH bpf-next v4 1/2] bpf, xdp: make bpf_redirect_map() a map operation Date: Fri, 26 Feb 2021 12:23:21 +0100 Message-Id: <20210226112322.144927-2-bjorn.topel@gmail.com> In-Reply-To: <20210226112322.144927-1-bjorn.topel@gmail.com> References: <20210226112322.144927-1-bjorn.topel@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	Optimize bpf_redirect_map()/xdp_do_redirect() \| expand [bpf-next,v4,0/2] Optimize bpf_redirect_map()/xdp_do_redirect() [bpf-next,v4,1/2] bpf, xdp: make bpf_redirect_map() a map operation [bpf-next,v4,2/2] bpf, xdp: restructure redirect actions

Context	Check	Description
netdev/cover_letter	success	Link
netdev/fixes_present	success	Link
netdev/patch_count	success	Link
netdev/tree_selection	success	Clearly marked for bpf-next
netdev/subject_prefix	success	Link
netdev/cc_maintainers	warning	7 maintainers not CCed: jonathan.lemon@gmail.com kpsingh@kernel.org songliubraving@fb.com yhs@fb.com kafai@fb.com bjorn@kernel.org andrii@kernel.org
netdev/source_inline	success	Was 1 now: 0
netdev/verify_signedoff	success	Link
netdev/module_param	success	Was 0 now: 0
netdev/build_32bit	fail	Errors and warnings before: 11771 this patch: 11773
netdev/kdoc	success	Errors and warnings before: 0 this patch: 0
netdev/verify_fixes	success	Link
netdev/checkpatch	warning	CHECK: Alignment should match open parenthesis WARNING: line length of 82 exceeds 80 columns WARNING: line length of 85 exceeds 80 columns WARNING: line length of 87 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns WARNING: line length of 98 exceeds 80 columns WARNING: line length of 99 exceeds 80 columns
netdev/build_allmodconfig_warn	fail	Errors and warnings before: 12418 this patch: 12420
netdev/header_inline	success	Link
netdev/stable	success	Stable not CCed

diff --git a/include/linux/bpf.h b/include/linux/bpf.h index cccaef1088ea..a44ba904ca37 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -117,6 +117,9 @@ struct bpf_map_ops { void *owner, u32 size); struct bpf_local_storage __rcu ** (*map_owner_storage_ptr)(void *owner); + /* XDP helpers.*/ + int (*xdp_redirect_map)(struct bpf_map *map, u32 ifindex, 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 * an inner map can be inserted to an outer map. @@ -1429,9 +1432,9 @@ struct btf *bpf_get_btf_vmlinux(void); /* Map specifics */ struct xdp_buff; struct sk_buff; +struct bpf_dtab_netdev; +struct bpf_cpu_map_entry; -struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key); -struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key); void __dev_flush(void); int dev_xdp_enqueue(struct net_device *dev, struct xdp_buff *xdp, struct net_device *dev_rx); @@ -1441,7 +1444,6 @@ int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb, struct bpf_prog *xdp_prog); bool dev_map_can_have_prog(struct bpf_map *map); -struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key); void __cpu_map_flush(void); int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_buff *xdp, struct net_device *dev_rx); @@ -1568,17 +1570,6 @@ static inline int bpf_obj_get_user(const char __user *pathname, int flags) return -EOPNOTSUPP; } -static inline struct net_device *__dev_map_lookup_elem(struct bpf_map *map, - u32 key) -{ - return NULL; -} - -static inline struct net_device *__dev_map_hash_lookup_elem(struct bpf_map *map, - u32 key) -{ - return NULL; -} static inline bool dev_map_can_have_prog(struct bpf_map *map) { return false; @@ -1590,6 +1581,7 @@ static inline void __dev_flush(void) struct xdp_buff; struct bpf_dtab_netdev; +struct bpf_cpu_map_entry; static inline int dev_xdp_enqueue(struct net_device *dev, struct xdp_buff *xdp, @@ -1614,12 +1606,6 @@ static inline int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, return 0; } -static inline -struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key) -{ - return NULL; -} - static inline void __cpu_map_flush(void) { } diff --git a/include/linux/filter.h b/include/linux/filter.h index 3b00fc906ccd..008691fd3b58 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -1472,4 +1472,31 @@ 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, u64 flags, + void *lookup_elem(struct bpf_map *map, u32 key)) +{ + struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + + /* Lower bits of the flags are used as return code on lookup failure */ + if (unlikely(flags > XDP_TX)) + return XDP_ABORTED; + + ri->tgt_value = lookup_elem(map, ifindex); + if (unlikely(!ri->tgt_value)) { + /* If the lookup fails we want to clear out the state in the + * redirect_info struct completely, so that if an eBPF program + * performs multiple lookups, the last one always takes + * precedence. + */ + WRITE_ONCE(ri->map, NULL); + return flags; + } + + ri->flags = flags; + ri->tgt_index = ifindex; + WRITE_ONCE(ri->map, map); + + return XDP_REDIRECT; +} + #endif /* __LINUX_FILTER_H__ */ diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h index cc17bc957548..9c0722c6d7ac 100644 --- a/include/net/xdp_sock.h +++ b/include/net/xdp_sock.h @@ -80,19 +80,6 @@ int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp); int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp); void __xsk_map_flush(void); -static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map, - u32 key) -{ - struct xsk_map *m = container_of(map, struct xsk_map, map); - struct xdp_sock *xs; - - if (key >= map->max_entries) - return NULL; - - xs = READ_ONCE(m->xsk_map[key]); - return xs; -} - #else static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) @@ -109,12 +96,6 @@ static inline void __xsk_map_flush(void) { } -static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map, - u32 key) -{ - return NULL; -} - #endif /* CONFIG_XDP_SOCKETS */ #endif /* _LINUX_XDP_SOCK_H */ diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index 5d1469de6921..85a2d33fd46b 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -563,7 +563,7 @@ static void cpu_map_free(struct bpf_map *map) kfree(cmap); } -struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key) +static void *__cpu_map_lookup_elem(struct bpf_map *map, u32 key) { struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map); struct bpf_cpu_map_entry *rcpu; @@ -600,6 +600,11 @@ static int cpu_map_get_next_key(struct bpf_map *map, void *key, void *next_key) return 0; } +static int cpu_map_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem); +} + static int cpu_map_btf_id; const struct bpf_map_ops cpu_map_ops = { .map_meta_equal = bpf_map_meta_equal, @@ -612,6 +617,7 @@ const struct bpf_map_ops cpu_map_ops = { .map_check_btf = map_check_no_btf, .map_btf_name = "bpf_cpu_map", .map_btf_id = &cpu_map_btf_id, + .xdp_redirect_map = cpu_map_xdp_redirect_map, }; static void bq_flush_to_queue(struct xdp_bulk_queue *bq) diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 85d9d1b72a33..adf9a2517f80 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -258,7 +258,7 @@ static int dev_map_get_next_key(struct bpf_map *map, void *key, void *next_key) return 0; } -struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key) +static void *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key) { struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map); struct hlist_head *head = dev_map_index_hash(dtab, key); @@ -392,7 +392,7 @@ void __dev_flush(void) * update happens in parallel here a dev_put wont happen until after reading the * ifindex. */ -struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key) +static void *__dev_map_lookup_elem(struct bpf_map *map, u32 key) { struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map); struct bpf_dtab_netdev *obj; @@ -735,6 +735,16 @@ static int dev_map_hash_update_elem(struct bpf_map *map, void *key, void *value, map, key, value, map_flags); } +static int dev_map_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem); +} + +static int dev_hash_map_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem); +} + static int dev_map_btf_id; const struct bpf_map_ops dev_map_ops = { .map_meta_equal = bpf_map_meta_equal, @@ -747,6 +757,7 @@ const struct bpf_map_ops dev_map_ops = { .map_check_btf = map_check_no_btf, .map_btf_name = "bpf_dtab", .map_btf_id = &dev_map_btf_id, + .xdp_redirect_map = dev_map_xdp_redirect_map, }; static int dev_map_hash_map_btf_id; @@ -761,6 +772,7 @@ const struct bpf_map_ops dev_map_hash_ops = { .map_check_btf = map_check_no_btf, .map_btf_name = "bpf_dtab", .map_btf_id = &dev_map_hash_map_btf_id, + .xdp_redirect_map = dev_hash_map_xdp_redirect_map, }; static void dev_map_hash_remove_netdev(struct bpf_dtab *dtab, diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 1dda9d81f12c..96705a49225e 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5409,7 +5409,8 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta, func_id != BPF_FUNC_map_delete_elem && func_id != BPF_FUNC_map_push_elem && func_id != BPF_FUNC_map_pop_elem && - func_id != BPF_FUNC_map_peek_elem) + func_id != BPF_FUNC_map_peek_elem && + func_id != BPF_FUNC_redirect_map) return 0; if (map == NULL) { @@ -11762,7 +11763,8 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) insn->imm == BPF_FUNC_map_delete_elem || insn->imm == BPF_FUNC_map_push_elem || insn->imm == BPF_FUNC_map_pop_elem || - insn->imm == BPF_FUNC_map_peek_elem)) { + insn->imm == BPF_FUNC_map_peek_elem || + insn->imm == BPF_FUNC_redirect_map)) { aux = &env->insn_aux_data[i + delta]; if (bpf_map_ptr_poisoned(aux)) goto patch_call_imm; @@ -11804,6 +11806,8 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) (int (*)(struct bpf_map *map, void *value))NULL)); BUILD_BUG_ON(!__same_type(ops->map_peek_elem, (int (*)(struct bpf_map *map, void *value))NULL)); + BUILD_BUG_ON(!__same_type(ops->xdp_redirect_map, + (int (*)(struct bpf_map *map, u32 ifindex, u64 flags))NULL)); patch_map_ops_generic: switch (insn->imm) { case BPF_FUNC_map_lookup_elem: @@ -11830,6 +11834,9 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) insn->imm = BPF_CAST_CALL(ops->map_peek_elem) - __bpf_call_base; continue; + case BPF_FUNC_redirect_map: + insn->imm = BPF_CAST_CALL(ops->xdp_redirect_map) - __bpf_call_base; + continue; } goto patch_call_imm; diff --git a/net/core/filter.c b/net/core/filter.c index adfdad234674..fdf7401f43fd 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3944,22 +3944,6 @@ void xdp_do_flush(void) } EXPORT_SYMBOL_GPL(xdp_do_flush); -static inline void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index) -{ - switch (map->map_type) { - case BPF_MAP_TYPE_DEVMAP: - return __dev_map_lookup_elem(map, index); - case BPF_MAP_TYPE_DEVMAP_HASH: - return __dev_map_hash_lookup_elem(map, index); - case BPF_MAP_TYPE_CPUMAP: - return __cpu_map_lookup_elem(map, index); - case BPF_MAP_TYPE_XSKMAP: - return __xsk_map_lookup_elem(map, index); - default: - return NULL; - } -} - void bpf_clear_redirect_map(struct bpf_map *map) { struct bpf_redirect_info *ri; @@ -4113,28 +4097,7 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = { BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags) { - struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); - - /* Lower bits of the flags are used as return code on lookup failure */ - if (unlikely(flags > XDP_TX)) - return XDP_ABORTED; - - ri->tgt_value = __xdp_map_lookup_elem(map, ifindex); - if (unlikely(!ri->tgt_value)) { - /* If the lookup fails we want to clear out the state in the - * redirect_info struct completely, so that if an eBPF program - * performs multiple lookups, the last one always takes - * precedence. - */ - WRITE_ONCE(ri->map, NULL); - return flags; - } - - ri->flags = flags; - ri->tgt_index = ifindex; - WRITE_ONCE(ri->map, map); - - return XDP_REDIRECT; + return map->ops->xdp_redirect_map(map, ifindex, flags); } static const struct bpf_func_proto bpf_xdp_redirect_map_proto = { diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c index 113fd9017203..92f4023d3ae2 100644 --- a/net/xdp/xskmap.c +++ b/net/xdp/xskmap.c @@ -125,6 +125,18 @@ static int xsk_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf) return insn - insn_buf; } +static void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key) +{ + struct xsk_map *m = container_of(map, struct xsk_map, map); + struct xdp_sock *xs; + + if (key >= map->max_entries) + return NULL; + + xs = READ_ONCE(m->xsk_map[key]); + return xs; +} + static void *xsk_map_lookup_elem(struct bpf_map *map, void *key) { WARN_ON_ONCE(!rcu_read_lock_held()); @@ -215,6 +227,11 @@ static int xsk_map_delete_elem(struct bpf_map *map, void *key) return 0; } +static int xsk_map_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem); +} + void xsk_map_try_sock_delete(struct xsk_map *map, struct xdp_sock *xs, struct xdp_sock **map_entry) { @@ -247,4 +264,5 @@ const struct bpf_map_ops xsk_map_ops = { .map_check_btf = map_check_no_btf, .map_btf_name = "xsk_map", .map_btf_id = &xsk_map_btf_id, + .xdp_redirect_map = xsk_map_xdp_redirect_map, };

[bpf-next,v4,1/2] bpf, xdp: make bpf_redirect_map() a map operation

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