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[213.102.90.208]) by smtp.gmail.com with ESMTPSA id d9sm974092lfl.290.2021.02.19.06.59.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Feb 2021 06:59:33 -0800 (PST) From: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= To: ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, bpf@vger.kernel.org Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , 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 1/2] bpf, xdp: per-map bpf_redirect_map functions for XDP Date: Fri, 19 Feb 2021 15:59:21 +0100 Message-Id: <20210219145922.63655-2-bjorn.topel@gmail.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210219145922.63655-1-bjorn.topel@gmail.com> References: <20210219145922.63655-1-bjorn.topel@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Björn Töpel Currently the bpf_redirect_map() implementation dispatches to the correct map-lookup function via a switch-statement. To avoid the dispatching, this change adds one bpf_redirect_map() implementation per map. Correct function is automatically selected by the BPF verifier. rfc->v1: Get rid of the macro and use __always_inline. (Jesper) Signed-off-by: Björn Töpel --- include/linux/bpf.h | 20 +++++++------ include/linux/filter.h | 2 ++ include/net/xdp_sock.h | 6 ++-- kernel/bpf/cpumap.c | 2 +- kernel/bpf/devmap.c | 4 +-- kernel/bpf/verifier.c | 28 +++++++++++------- net/core/filter.c | 67 ++++++++++++++++++++++++++---------------- 7 files changed, 76 insertions(+), 53 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index cccaef1088ea..3dd186eeaf98 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -314,12 +314,14 @@ enum bpf_return_type { RET_PTR_TO_BTF_ID, /* returns a pointer to a btf_id */ }; +typedef u64 (*bpf_func_proto_func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); + /* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL * instructions after verifying */ struct bpf_func_proto { - u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); + bpf_func_proto_func func; bool gpl_only; bool pkt_access; enum bpf_return_type ret_type; @@ -1429,9 +1431,11 @@ 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_map_lookup_elem(struct bpf_map *map, u32 key); +void *__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 +1445,7 @@ 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_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); @@ -1568,14 +1572,12 @@ 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) +static inline void *__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) +static inline void *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key) { return NULL; } @@ -1615,7 +1617,7 @@ static inline int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, } static inline -struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key) +void *__cpu_map_lookup_elem(struct bpf_map *map, u32 key) { return NULL; } diff --git a/include/linux/filter.h b/include/linux/filter.h index 3b00fc906ccd..1dedcf66b694 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -1472,4 +1472,6 @@ static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol, } #endif /* IS_ENABLED(CONFIG_IPV6) */ +bpf_func_proto_func get_xdp_redirect_func(enum bpf_map_type map_type); + #endif /* __LINUX_FILTER_H__ */ diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h index cc17bc957548..da4139a58630 100644 --- a/include/net/xdp_sock.h +++ b/include/net/xdp_sock.h @@ -80,8 +80,7 @@ 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) +static inline 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; @@ -109,8 +108,7 @@ static inline void __xsk_map_flush(void) { } -static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map, - u32 key) +static inline void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key) { return NULL; } diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index 5d1469de6921..a4d2cb93cd69 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) +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; diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 85d9d1b72a33..37ac4cde9713 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) +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) +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; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 3d34ba492d46..b5fb0c4e911a 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) { @@ -11860,17 +11861,22 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) } patch_call_imm: - fn = env->ops->get_func_proto(insn->imm, env->prog); - /* all functions that have prototype and verifier allowed - * programs to call them, must be real in-kernel functions - */ - if (!fn->func) { - verbose(env, - "kernel subsystem misconfigured func %s#%d\n", - func_id_name(insn->imm), insn->imm); - return -EFAULT; + if (insn->imm == BPF_FUNC_redirect_map) { + aux = &env->insn_aux_data[i]; + map_ptr = BPF_MAP_PTR(aux->map_ptr_state); + insn->imm = get_xdp_redirect_func(map_ptr->map_type) - __bpf_call_base; + } else { + fn = env->ops->get_func_proto(insn->imm, env->prog); + /* all functions that have prototype and verifier allowed + * programs to call them, must be real in-kernel functions + */ + if (!fn->func) { + verbose(env, "kernel subsystem misconfigured func %s#%d\n", + func_id_name(insn->imm), insn->imm); + return -EFAULT; + } + insn->imm = fn->func - __bpf_call_base; } - insn->imm = fn->func - __bpf_call_base; } /* Since poke tab is now finalized, publish aux to tracker. */ diff --git a/net/core/filter.c b/net/core/filter.c index adfdad234674..fd64d768e16a 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; @@ -4110,22 +4094,17 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = { .arg2_type = ARG_ANYTHING, }; -BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, - u64, flags) +static __always_inline s64 __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 = __xdp_map_lookup_elem(map, ifindex); + 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; } @@ -4137,8 +4116,44 @@ BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, return XDP_REDIRECT; } +BPF_CALL_3(bpf_xdp_redirect_devmap, struct bpf_map *, map, u32, ifindex, u64, flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem); +} + +BPF_CALL_3(bpf_xdp_redirect_devmap_hash, struct bpf_map *, map, u32, ifindex, u64, flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem); +} + +BPF_CALL_3(bpf_xdp_redirect_cpumap, struct bpf_map *, map, u32, ifindex, u64, flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem); +} + +BPF_CALL_3(bpf_xdp_redirect_xskmap, struct bpf_map *, map, u32, ifindex, u64, flags) +{ + return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem); +} + +bpf_func_proto_func get_xdp_redirect_func(enum bpf_map_type map_type) +{ + switch (map_type) { + case BPF_MAP_TYPE_DEVMAP: + return bpf_xdp_redirect_devmap; + case BPF_MAP_TYPE_DEVMAP_HASH: + return bpf_xdp_redirect_devmap_hash; + case BPF_MAP_TYPE_CPUMAP: + return bpf_xdp_redirect_cpumap; + case BPF_MAP_TYPE_XSKMAP: + return bpf_xdp_redirect_xskmap; + default: + return NULL; + } +} + +/* NB! .func is NULL! get_xdp_redirect_func() is used instead! */ static const struct bpf_func_proto bpf_xdp_redirect_map_proto = { - .func = bpf_xdp_redirect_map, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, From patchwork Fri Feb 19 14:59:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= X-Patchwork-Id: 385214 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35481C4332D for ; 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[213.102.90.208]) by smtp.gmail.com with ESMTPSA id d9sm974092lfl.290.2021.02.19.06.59.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Feb 2021 06:59:34 -0800 (PST) From: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= To: ast@kernel.org, daniel@iogearbox.net, netdev@vger.kernel.org, bpf@vger.kernel.org Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , 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 2/2] bpf, xdp: restructure redirect actions Date: Fri, 19 Feb 2021 15:59:22 +0100 Message-Id: <20210219145922.63655-3-bjorn.topel@gmail.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210219145922.63655-1-bjorn.topel@gmail.com> References: <20210219145922.63655-1-bjorn.topel@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Björn Töpel The XDP_REDIRECT implementations for maps and non-maps are fairly similar, but obviously need to take different code paths depending on if the target is using a map or not. Today, the redirect targets for XDP either uses a map, or is based on ifindex. Here, an explicit redirect type is added to bpf_redirect_info, instead of the actual map. Redirect type, map item/ifindex, and the map_id (if any) is passed to xdp_do_redirect(). In addition to making the code easier to follow, using an explicit type in bpf_redirect_info has a slight positive performance impact by avoiding a pointer indirection for the map type lookup, and instead use the cacheline for bpf_redirect_info. Since the actual map is not passed via bpf_redirect_info anymore, the map lookup is only done in the BPF helper. This means that the bpf_clear_redirect_map() function can be removed. The actual map item is RCU protected. The bpf_redirect_info flags member is not used by XDP, and not read/written any more. The map member is only written to when required/used, and not unconditionally. rfc->v1: Use map_id, and remove bpf_clear_redirect_map(). (Toke) Reviewed-by: Maciej Fijalkowski Signed-off-by: Björn Töpel --- include/linux/filter.h | 11 ++- include/trace/events/xdp.h | 66 +++++++++------ kernel/bpf/cpumap.c | 1 - kernel/bpf/devmap.c | 1 - net/core/filter.c | 162 ++++++++++++++++--------------------- net/xdp/xskmap.c | 1 - 6 files changed, 121 insertions(+), 121 deletions(-) diff --git a/include/linux/filter.h b/include/linux/filter.h index 1dedcf66b694..1f3cf2a1e116 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -646,11 +646,20 @@ struct bpf_redirect_info { u32 flags; u32 tgt_index; void *tgt_value; - struct bpf_map *map; + u32 map_id; + u32 tgt_type; u32 kern_flags; struct bpf_nh_params nh; }; +enum xdp_redirect_type { + XDP_REDIR_UNSET, + XDP_REDIR_DEV_IFINDEX, + XDP_REDIR_DEV_MAP, + XDP_REDIR_CPU_MAP, + XDP_REDIR_XSK_MAP, +}; + DECLARE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info); /* flags for bpf_redirect_info kern_flags */ diff --git a/include/trace/events/xdp.h b/include/trace/events/xdp.h index 76a97176ab81..538321735447 100644 --- a/include/trace/events/xdp.h +++ b/include/trace/events/xdp.h @@ -86,19 +86,15 @@ struct _bpf_dtab_netdev { }; #endif /* __DEVMAP_OBJ_TYPE */ -#define devmap_ifindex(tgt, map) \ - (((map->map_type == BPF_MAP_TYPE_DEVMAP || \ - map->map_type == BPF_MAP_TYPE_DEVMAP_HASH)) ? \ - ((struct _bpf_dtab_netdev *)tgt)->dev->ifindex : 0) - DECLARE_EVENT_CLASS(xdp_redirect_template, TP_PROTO(const struct net_device *dev, const struct bpf_prog *xdp, const void *tgt, int err, - const struct bpf_map *map, u32 index), + enum xdp_redirect_type type, + const struct bpf_redirect_info *ri), - TP_ARGS(dev, xdp, tgt, err, map, index), + TP_ARGS(dev, xdp, tgt, err, type, ri), TP_STRUCT__entry( __field(int, prog_id) @@ -111,14 +107,30 @@ DECLARE_EVENT_CLASS(xdp_redirect_template, ), TP_fast_assign( + u32 ifindex = 0, map_id = 0, index = ri->tgt_index; + + switch (type) { + case XDP_REDIR_DEV_MAP: + ifindex = ((struct _bpf_dtab_netdev *)tgt)->dev->ifindex; + fallthrough; + case XDP_REDIR_CPU_MAP: + case XDP_REDIR_XSK_MAP: + map_id = ri->map_id; + break; + case XDP_REDIR_DEV_IFINDEX: + ifindex = (u32)(long)tgt; + break; + default: + break; + } + __entry->prog_id = xdp->aux->id; __entry->act = XDP_REDIRECT; __entry->ifindex = dev->ifindex; __entry->err = err; - __entry->to_ifindex = map ? devmap_ifindex(tgt, map) : - index; - __entry->map_id = map ? map->id : 0; - __entry->map_index = map ? index : 0; + __entry->to_ifindex = ifindex; + __entry->map_id = map_id; + __entry->map_index = index; ), TP_printk("prog_id=%d action=%s ifindex=%d to_ifindex=%d err=%d" @@ -133,45 +145,49 @@ DEFINE_EVENT(xdp_redirect_template, xdp_redirect, TP_PROTO(const struct net_device *dev, const struct bpf_prog *xdp, const void *tgt, int err, - const struct bpf_map *map, u32 index), - TP_ARGS(dev, xdp, tgt, err, map, index) + enum xdp_redirect_type type, + const struct bpf_redirect_info *ri), + TP_ARGS(dev, xdp, tgt, err, type, ri) ); DEFINE_EVENT(xdp_redirect_template, xdp_redirect_err, TP_PROTO(const struct net_device *dev, const struct bpf_prog *xdp, const void *tgt, int err, - const struct bpf_map *map, u32 index), - TP_ARGS(dev, xdp, tgt, err, map, index) + enum xdp_redirect_type type, + const struct bpf_redirect_info *ri), + TP_ARGS(dev, xdp, tgt, err, type, ri) ); #define _trace_xdp_redirect(dev, xdp, to) \ - trace_xdp_redirect(dev, xdp, NULL, 0, NULL, to) + trace_xdp_redirect(dev, xdp, NULL, 0, XDP_REDIR_DEV_IFINDEX, NULL) #define _trace_xdp_redirect_err(dev, xdp, to, err) \ - trace_xdp_redirect_err(dev, xdp, NULL, err, NULL, to) + trace_xdp_redirect_err(dev, xdp, NULL, err, XDP_REDIR_DEV_IFINDEX, NULL) -#define _trace_xdp_redirect_map(dev, xdp, to, map, index) \ - trace_xdp_redirect(dev, xdp, to, 0, map, index) +#define _trace_xdp_redirect_map(dev, xdp, to, type, ri) \ + trace_xdp_redirect(dev, xdp, to, 0, type, ri) -#define _trace_xdp_redirect_map_err(dev, xdp, to, map, index, err) \ - trace_xdp_redirect_err(dev, xdp, to, err, map, index) +#define _trace_xdp_redirect_map_err(dev, xdp, to, type, ri, err) \ + trace_xdp_redirect_err(dev, xdp, to, err, type, ri) /* not used anymore, but kept around so as not to break old programs */ DEFINE_EVENT(xdp_redirect_template, xdp_redirect_map, TP_PROTO(const struct net_device *dev, const struct bpf_prog *xdp, const void *tgt, int err, - const struct bpf_map *map, u32 index), - TP_ARGS(dev, xdp, tgt, err, map, index) + enum xdp_redirect_type type, + const struct bpf_redirect_info *ri), + TP_ARGS(dev, xdp, tgt, err, type, ri) ); DEFINE_EVENT(xdp_redirect_template, xdp_redirect_map_err, TP_PROTO(const struct net_device *dev, const struct bpf_prog *xdp, const void *tgt, int err, - const struct bpf_map *map, u32 index), - TP_ARGS(dev, xdp, tgt, err, map, index) + enum xdp_redirect_type type, + const struct bpf_redirect_info *ri), + TP_ARGS(dev, xdp, tgt, err, type, ri) ); TRACE_EVENT(xdp_cpumap_kthread, diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index a4d2cb93cd69..b7f4d22f5c8d 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -543,7 +543,6 @@ static void cpu_map_free(struct bpf_map *map) * complete. */ - bpf_clear_redirect_map(map); synchronize_rcu(); /* For cpu_map the remote CPUs can still be using the entries diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 37ac4cde9713..b5681a98020d 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -197,7 +197,6 @@ static void dev_map_free(struct bpf_map *map) list_del_rcu(&dtab->list); spin_unlock(&dev_map_lock); - bpf_clear_redirect_map(map); synchronize_rcu(); /* Make sure prior __dev_map_entry_free() have completed. */ diff --git a/net/core/filter.c b/net/core/filter.c index fd64d768e16a..56074b88d7e2 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3919,23 +3919,6 @@ static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = { .arg2_type = ARG_ANYTHING, }; -static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, - struct bpf_map *map, struct xdp_buff *xdp) -{ - switch (map->map_type) { - case BPF_MAP_TYPE_DEVMAP: - case BPF_MAP_TYPE_DEVMAP_HASH: - return dev_map_enqueue(fwd, xdp, dev_rx); - case BPF_MAP_TYPE_CPUMAP: - return cpu_map_enqueue(fwd, xdp, dev_rx); - case BPF_MAP_TYPE_XSKMAP: - return __xsk_map_redirect(fwd, xdp); - default: - return -EBADRQC; - } - return 0; -} - void xdp_do_flush(void) { __dev_flush(); @@ -3944,55 +3927,45 @@ void xdp_do_flush(void) } EXPORT_SYMBOL_GPL(xdp_do_flush); -void bpf_clear_redirect_map(struct bpf_map *map) -{ - struct bpf_redirect_info *ri; - int cpu; - - for_each_possible_cpu(cpu) { - ri = per_cpu_ptr(&bpf_redirect_info, cpu); - /* Avoid polluting remote cacheline due to writes if - * not needed. Once we pass this test, we need the - * cmpxchg() to make sure it hasn't been changed in - * the meantime by remote CPU. - */ - if (unlikely(READ_ONCE(ri->map) == map)) - cmpxchg(&ri->map, map, NULL); - } -} - int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, struct bpf_prog *xdp_prog) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); - struct bpf_map *map = READ_ONCE(ri->map); - u32 index = ri->tgt_index; + enum xdp_redirect_type type = ri->tgt_type; void *fwd = ri->tgt_value; int err; - ri->tgt_index = 0; - ri->tgt_value = NULL; - WRITE_ONCE(ri->map, NULL); + ri->tgt_type = XDP_REDIR_UNSET; - if (unlikely(!map)) { - fwd = dev_get_by_index_rcu(dev_net(dev), index); + switch (type) { + case XDP_REDIR_DEV_IFINDEX: + fwd = dev_get_by_index_rcu(dev_net(dev), (u32)(long)fwd); if (unlikely(!fwd)) { err = -EINVAL; - goto err; + break; } - err = dev_xdp_enqueue(fwd, xdp, dev); - } else { - err = __bpf_tx_xdp_map(dev, fwd, map, xdp); + break; + case XDP_REDIR_DEV_MAP: + err = dev_map_enqueue(fwd, xdp, dev); + break; + case XDP_REDIR_CPU_MAP: + err = cpu_map_enqueue(fwd, xdp, dev); + break; + case XDP_REDIR_XSK_MAP: + err = __xsk_map_redirect(fwd, xdp); + break; + default: + err = -EBADRQC; } if (unlikely(err)) goto err; - _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); + _trace_xdp_redirect_map(dev, xdp_prog, fwd, type, ri); return 0; err: - _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); + _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, type, ri, err); return err; } EXPORT_SYMBOL_GPL(xdp_do_redirect); @@ -4001,41 +3974,40 @@ static int xdp_do_generic_redirect_map(struct net_device *dev, struct sk_buff *skb, struct xdp_buff *xdp, struct bpf_prog *xdp_prog, - struct bpf_map *map) + void *fwd, + enum xdp_redirect_type type) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); - u32 index = ri->tgt_index; - void *fwd = ri->tgt_value; - int err = 0; - - ri->tgt_index = 0; - ri->tgt_value = NULL; - WRITE_ONCE(ri->map, NULL); + int err; - if (map->map_type == BPF_MAP_TYPE_DEVMAP || - map->map_type == BPF_MAP_TYPE_DEVMAP_HASH) { + switch (type) { + case XDP_REDIR_DEV_MAP: { struct bpf_dtab_netdev *dst = fwd; err = dev_map_generic_redirect(dst, skb, xdp_prog); if (unlikely(err)) goto err; - } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) { + break; + } + case XDP_REDIR_XSK_MAP: { struct xdp_sock *xs = fwd; err = xsk_generic_rcv(xs, xdp); if (err) goto err; consume_skb(skb); - } else { + break; + } + default: /* TODO: Handle BPF_MAP_TYPE_CPUMAP */ err = -EBADRQC; goto err; } - _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); + _trace_xdp_redirect_map(dev, xdp_prog, fwd, type, ri); return 0; err: - _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err); + _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, type, ri, err); return err; } @@ -4043,29 +4015,31 @@ int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, struct xdp_buff *xdp, struct bpf_prog *xdp_prog) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); - struct bpf_map *map = READ_ONCE(ri->map); - u32 index = ri->tgt_index; - struct net_device *fwd; + enum xdp_redirect_type type = ri->tgt_type; + void *fwd = ri->tgt_value; int err = 0; - if (map) - return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, - map); - ri->tgt_index = 0; - fwd = dev_get_by_index_rcu(dev_net(dev), index); - if (unlikely(!fwd)) { - err = -EINVAL; - goto err; - } + ri->tgt_type = XDP_REDIR_UNSET; + ri->tgt_value = NULL; - err = xdp_ok_fwd_dev(fwd, skb->len); - if (unlikely(err)) - goto err; + if (type == XDP_REDIR_DEV_IFINDEX) { + fwd = dev_get_by_index_rcu(dev_net(dev), (u32)(long)fwd); + if (unlikely(!fwd)) { + err = -EINVAL; + goto err; + } - skb->dev = fwd; - _trace_xdp_redirect(dev, xdp_prog, index); - generic_xdp_tx(skb, xdp_prog); - return 0; + err = xdp_ok_fwd_dev(fwd, skb->len); + if (unlikely(err)) + goto err; + + skb->dev = fwd; + _trace_xdp_redirect(dev, xdp_prog, index); + generic_xdp_tx(skb, xdp_prog); + return 0; + } + + return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, type); err: _trace_xdp_redirect_err(dev, xdp_prog, index, err); return err; @@ -4078,10 +4052,9 @@ BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags) if (unlikely(flags)) return XDP_ABORTED; - ri->flags = flags; - ri->tgt_index = ifindex; - ri->tgt_value = NULL; - WRITE_ONCE(ri->map, NULL); + ri->tgt_type = XDP_REDIR_DEV_IFINDEX; + ri->tgt_index = 0; + ri->tgt_value = (void *)(long)ifindex; return XDP_REDIRECT; } @@ -4096,7 +4069,8 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = { static __always_inline s64 __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags, void *lookup_elem(struct bpf_map *map, - u32 key)) + u32 key), + enum xdp_redirect_type type) { struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); @@ -4105,35 +4079,39 @@ static __always_inline s64 __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifind ri->tgt_value = lookup_elem(map, ifindex); if (unlikely(!ri->tgt_value)) { - WRITE_ONCE(ri->map, NULL); + ri->tgt_type = XDP_REDIR_UNSET; return flags; } - ri->flags = flags; ri->tgt_index = ifindex; - WRITE_ONCE(ri->map, map); + ri->tgt_type = type; + ri->map_id = map->id; return XDP_REDIRECT; } BPF_CALL_3(bpf_xdp_redirect_devmap, struct bpf_map *, map, u32, ifindex, u64, flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem, + XDP_REDIR_DEV_MAP); } BPF_CALL_3(bpf_xdp_redirect_devmap_hash, struct bpf_map *, map, u32, ifindex, u64, flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem, + XDP_REDIR_DEV_MAP); } BPF_CALL_3(bpf_xdp_redirect_cpumap, struct bpf_map *, map, u32, ifindex, u64, flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem, + XDP_REDIR_CPU_MAP); } BPF_CALL_3(bpf_xdp_redirect_xskmap, struct bpf_map *, map, u32, ifindex, u64, flags) { - return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem); + return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem, + XDP_REDIR_XSK_MAP); } bpf_func_proto_func get_xdp_redirect_func(enum bpf_map_type map_type) diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c index 113fd9017203..c285d3dd04ad 100644 --- a/net/xdp/xskmap.c +++ b/net/xdp/xskmap.c @@ -87,7 +87,6 @@ static void xsk_map_free(struct bpf_map *map) { struct xsk_map *m = container_of(map, struct xsk_map, map); - bpf_clear_redirect_map(map); synchronize_net(); bpf_map_area_free(m); }