| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* include/net/xdp.h |
| * |
| * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc. |
| */ |
| #ifndef __LINUX_NET_XDP_H__ |
| #define __LINUX_NET_XDP_H__ |
| |
| #include <linux/skbuff.h> /* skb_shared_info */ |
| #include <uapi/linux/netdev.h> |
| #include <linux/bitfield.h> |
| |
| /** |
| * DOC: XDP RX-queue information |
| * |
| * The XDP RX-queue info (xdp_rxq_info) is associated with the driver |
| * level RX-ring queues. It is information that is specific to how |
| * the driver have configured a given RX-ring queue. |
| * |
| * Each xdp_buff frame received in the driver carries a (pointer) |
| * reference to this xdp_rxq_info structure. This provides the XDP |
| * data-path read-access to RX-info for both kernel and bpf-side |
| * (limited subset). |
| * |
| * For now, direct access is only safe while running in NAPI/softirq |
| * context. Contents are read-mostly and must not be updated during |
| * driver NAPI/softirq poll. |
| * |
| * The driver usage API is a register and unregister API. |
| * |
| * The struct is not directly tied to the XDP prog. A new XDP prog |
| * can be attached as long as it doesn't change the underlying |
| * RX-ring. If the RX-ring does change significantly, the NIC driver |
| * naturally need to stop the RX-ring before purging and reallocating |
| * memory. In that process the driver MUST call unregister (which |
| * also applies for driver shutdown and unload). The register API is |
| * also mandatory during RX-ring setup. |
| */ |
| |
| enum xdp_mem_type { |
| MEM_TYPE_PAGE_SHARED = 0, /* Split-page refcnt based model */ |
| MEM_TYPE_PAGE_ORDER0, /* Orig XDP full page model */ |
| MEM_TYPE_PAGE_POOL, |
| MEM_TYPE_XSK_BUFF_POOL, |
| MEM_TYPE_MAX, |
| }; |
| |
| typedef u32 xdp_features_t; |
| |
| /* XDP flags for ndo_xdp_xmit */ |
| #define XDP_XMIT_FLUSH (1U << 0) /* doorbell signal consumer */ |
| #define XDP_XMIT_FLAGS_MASK XDP_XMIT_FLUSH |
| |
| struct xdp_mem_info { |
| u32 type; /* enum xdp_mem_type, but known size type */ |
| u32 id; |
| }; |
| |
| struct page_pool; |
| |
| struct xdp_rxq_info { |
| struct net_device *dev; |
| u32 queue_index; |
| u32 reg_state; |
| struct xdp_mem_info mem; |
| unsigned int napi_id; |
| u32 frag_size; |
| } ____cacheline_aligned; /* perf critical, avoid false-sharing */ |
| |
| struct xdp_txq_info { |
| struct net_device *dev; |
| }; |
| |
| enum xdp_buff_flags { |
| XDP_FLAGS_HAS_FRAGS = BIT(0), /* non-linear xdp buff */ |
| XDP_FLAGS_FRAGS_PF_MEMALLOC = BIT(1), /* xdp paged memory is under |
| * pressure |
| */ |
| }; |
| |
| struct xdp_buff { |
| void *data; |
| void *data_end; |
| void *data_meta; |
| void *data_hard_start; |
| struct xdp_rxq_info *rxq; |
| struct xdp_txq_info *txq; |
| u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/ |
| u32 flags; /* supported values defined in xdp_buff_flags */ |
| }; |
| |
| static __always_inline bool xdp_buff_has_frags(struct xdp_buff *xdp) |
| { |
| return !!(xdp->flags & XDP_FLAGS_HAS_FRAGS); |
| } |
| |
| static __always_inline void xdp_buff_set_frags_flag(struct xdp_buff *xdp) |
| { |
| xdp->flags |= XDP_FLAGS_HAS_FRAGS; |
| } |
| |
| static __always_inline void xdp_buff_clear_frags_flag(struct xdp_buff *xdp) |
| { |
| xdp->flags &= ~XDP_FLAGS_HAS_FRAGS; |
| } |
| |
| static __always_inline bool xdp_buff_is_frag_pfmemalloc(struct xdp_buff *xdp) |
| { |
| return !!(xdp->flags & XDP_FLAGS_FRAGS_PF_MEMALLOC); |
| } |
| |
| static __always_inline void xdp_buff_set_frag_pfmemalloc(struct xdp_buff *xdp) |
| { |
| xdp->flags |= XDP_FLAGS_FRAGS_PF_MEMALLOC; |
| } |
| |
| static __always_inline void |
| xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq) |
| { |
| xdp->frame_sz = frame_sz; |
| xdp->rxq = rxq; |
| xdp->flags = 0; |
| } |
| |
| static __always_inline void |
| xdp_prepare_buff(struct xdp_buff *xdp, unsigned char *hard_start, |
| int headroom, int data_len, const bool meta_valid) |
| { |
| unsigned char *data = hard_start + headroom; |
| |
| xdp->data_hard_start = hard_start; |
| xdp->data = data; |
| xdp->data_end = data + data_len; |
| xdp->data_meta = meta_valid ? data : data + 1; |
| } |
| |
| /* Reserve memory area at end-of data area. |
| * |
| * This macro reserves tailroom in the XDP buffer by limiting the |
| * XDP/BPF data access to data_hard_end. Notice same area (and size) |
| * is used for XDP_PASS, when constructing the SKB via build_skb(). |
| */ |
| #define xdp_data_hard_end(xdp) \ |
| ((xdp)->data_hard_start + (xdp)->frame_sz - \ |
| SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) |
| |
| static inline struct skb_shared_info * |
| xdp_get_shared_info_from_buff(struct xdp_buff *xdp) |
| { |
| return (struct skb_shared_info *)xdp_data_hard_end(xdp); |
| } |
| |
| static __always_inline unsigned int xdp_get_buff_len(struct xdp_buff *xdp) |
| { |
| unsigned int len = xdp->data_end - xdp->data; |
| struct skb_shared_info *sinfo; |
| |
| if (likely(!xdp_buff_has_frags(xdp))) |
| goto out; |
| |
| sinfo = xdp_get_shared_info_from_buff(xdp); |
| len += sinfo->xdp_frags_size; |
| out: |
| return len; |
| } |
| |
| struct xdp_frame { |
| void *data; |
| u16 len; |
| u16 headroom; |
| u32 metasize; /* uses lower 8-bits */ |
| /* Lifetime of xdp_rxq_info is limited to NAPI/enqueue time, |
| * while mem info is valid on remote CPU. |
| */ |
| struct xdp_mem_info mem; |
| struct net_device *dev_rx; /* used by cpumap */ |
| u32 frame_sz; |
| u32 flags; /* supported values defined in xdp_buff_flags */ |
| }; |
| |
| static __always_inline bool xdp_frame_has_frags(struct xdp_frame *frame) |
| { |
| return !!(frame->flags & XDP_FLAGS_HAS_FRAGS); |
| } |
| |
| static __always_inline bool xdp_frame_is_frag_pfmemalloc(struct xdp_frame *frame) |
| { |
| return !!(frame->flags & XDP_FLAGS_FRAGS_PF_MEMALLOC); |
| } |
| |
| #define XDP_BULK_QUEUE_SIZE 16 |
| struct xdp_frame_bulk { |
| int count; |
| void *xa; |
| void *q[XDP_BULK_QUEUE_SIZE]; |
| }; |
| |
| static __always_inline void xdp_frame_bulk_init(struct xdp_frame_bulk *bq) |
| { |
| /* bq->count will be zero'ed when bq->xa gets updated */ |
| bq->xa = NULL; |
| } |
| |
| static inline struct skb_shared_info * |
| xdp_get_shared_info_from_frame(struct xdp_frame *frame) |
| { |
| void *data_hard_start = frame->data - frame->headroom - sizeof(*frame); |
| |
| return (struct skb_shared_info *)(data_hard_start + frame->frame_sz - |
| SKB_DATA_ALIGN(sizeof(struct skb_shared_info))); |
| } |
| |
| struct xdp_cpumap_stats { |
| unsigned int redirect; |
| unsigned int pass; |
| unsigned int drop; |
| }; |
| |
| /* Clear kernel pointers in xdp_frame */ |
| static inline void xdp_scrub_frame(struct xdp_frame *frame) |
| { |
| frame->data = NULL; |
| frame->dev_rx = NULL; |
| } |
| |
| static inline void |
| xdp_update_skb_shared_info(struct sk_buff *skb, u8 nr_frags, |
| unsigned int size, unsigned int truesize, |
| bool pfmemalloc) |
| { |
| skb_shinfo(skb)->nr_frags = nr_frags; |
| |
| skb->len += size; |
| skb->data_len += size; |
| skb->truesize += truesize; |
| skb->pfmemalloc |= pfmemalloc; |
| } |
| |
| /* Avoids inlining WARN macro in fast-path */ |
| void xdp_warn(const char *msg, const char *func, const int line); |
| #define XDP_WARN(msg) xdp_warn(msg, __func__, __LINE__) |
| |
| struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp); |
| struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf, |
| struct sk_buff *skb, |
| struct net_device *dev); |
| struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf, |
| struct net_device *dev); |
| int xdp_alloc_skb_bulk(void **skbs, int n_skb, gfp_t gfp); |
| struct xdp_frame *xdpf_clone(struct xdp_frame *xdpf); |
| |
| static inline |
| void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp) |
| { |
| xdp->data_hard_start = frame->data - frame->headroom - sizeof(*frame); |
| xdp->data = frame->data; |
| xdp->data_end = frame->data + frame->len; |
| xdp->data_meta = frame->data - frame->metasize; |
| xdp->frame_sz = frame->frame_sz; |
| xdp->flags = frame->flags; |
| } |
| |
| static inline |
| int xdp_update_frame_from_buff(struct xdp_buff *xdp, |
| struct xdp_frame *xdp_frame) |
| { |
| int metasize, headroom; |
| |
| /* Assure headroom is available for storing info */ |
| headroom = xdp->data - xdp->data_hard_start; |
| metasize = xdp->data - xdp->data_meta; |
| metasize = metasize > 0 ? metasize : 0; |
| if (unlikely((headroom - metasize) < sizeof(*xdp_frame))) |
| return -ENOSPC; |
| |
| /* Catch if driver didn't reserve tailroom for skb_shared_info */ |
| if (unlikely(xdp->data_end > xdp_data_hard_end(xdp))) { |
| XDP_WARN("Driver BUG: missing reserved tailroom"); |
| return -ENOSPC; |
| } |
| |
| xdp_frame->data = xdp->data; |
| xdp_frame->len = xdp->data_end - xdp->data; |
| xdp_frame->headroom = headroom - sizeof(*xdp_frame); |
| xdp_frame->metasize = metasize; |
| xdp_frame->frame_sz = xdp->frame_sz; |
| xdp_frame->flags = xdp->flags; |
| |
| return 0; |
| } |
| |
| /* Convert xdp_buff to xdp_frame */ |
| static inline |
| struct xdp_frame *xdp_convert_buff_to_frame(struct xdp_buff *xdp) |
| { |
| struct xdp_frame *xdp_frame; |
| |
| if (xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL) |
| return xdp_convert_zc_to_xdp_frame(xdp); |
| |
| /* Store info in top of packet */ |
| xdp_frame = xdp->data_hard_start; |
| if (unlikely(xdp_update_frame_from_buff(xdp, xdp_frame) < 0)) |
| return NULL; |
| |
| /* rxq only valid until napi_schedule ends, convert to xdp_mem_info */ |
| xdp_frame->mem = xdp->rxq->mem; |
| |
| return xdp_frame; |
| } |
| |
| void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct, |
| struct xdp_buff *xdp); |
| void xdp_return_frame(struct xdp_frame *xdpf); |
| void xdp_return_frame_rx_napi(struct xdp_frame *xdpf); |
| void xdp_return_buff(struct xdp_buff *xdp); |
| void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq); |
| void xdp_return_frame_bulk(struct xdp_frame *xdpf, |
| struct xdp_frame_bulk *bq); |
| |
| /* When sending xdp_frame into the network stack, then there is no |
| * return point callback, which is needed to release e.g. DMA-mapping |
| * resources with page_pool. Thus, have explicit function to release |
| * frame resources. |
| */ |
| void __xdp_release_frame(void *data, struct xdp_mem_info *mem); |
| static inline void xdp_release_frame(struct xdp_frame *xdpf) |
| { |
| struct xdp_mem_info *mem = &xdpf->mem; |
| struct skb_shared_info *sinfo; |
| int i; |
| |
| /* Curr only page_pool needs this */ |
| if (mem->type != MEM_TYPE_PAGE_POOL) |
| return; |
| |
| if (likely(!xdp_frame_has_frags(xdpf))) |
| goto out; |
| |
| sinfo = xdp_get_shared_info_from_frame(xdpf); |
| for (i = 0; i < sinfo->nr_frags; i++) { |
| struct page *page = skb_frag_page(&sinfo->frags[i]); |
| |
| __xdp_release_frame(page_address(page), mem); |
| } |
| out: |
| __xdp_release_frame(xdpf->data, mem); |
| } |
| |
| static __always_inline unsigned int xdp_get_frame_len(struct xdp_frame *xdpf) |
| { |
| struct skb_shared_info *sinfo; |
| unsigned int len = xdpf->len; |
| |
| if (likely(!xdp_frame_has_frags(xdpf))) |
| goto out; |
| |
| sinfo = xdp_get_shared_info_from_frame(xdpf); |
| len += sinfo->xdp_frags_size; |
| out: |
| return len; |
| } |
| |
| int __xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq, |
| struct net_device *dev, u32 queue_index, |
| unsigned int napi_id, u32 frag_size); |
| static inline int |
| xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq, |
| struct net_device *dev, u32 queue_index, |
| unsigned int napi_id) |
| { |
| return __xdp_rxq_info_reg(xdp_rxq, dev, queue_index, napi_id, 0); |
| } |
| |
| void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq); |
| void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq); |
| bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq); |
| int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, |
| enum xdp_mem_type type, void *allocator); |
| void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq); |
| int xdp_reg_mem_model(struct xdp_mem_info *mem, |
| enum xdp_mem_type type, void *allocator); |
| void xdp_unreg_mem_model(struct xdp_mem_info *mem); |
| |
| /* Drivers not supporting XDP metadata can use this helper, which |
| * rejects any room expansion for metadata as a result. |
| */ |
| static __always_inline void |
| xdp_set_data_meta_invalid(struct xdp_buff *xdp) |
| { |
| xdp->data_meta = xdp->data + 1; |
| } |
| |
| static __always_inline bool |
| xdp_data_meta_unsupported(const struct xdp_buff *xdp) |
| { |
| return unlikely(xdp->data_meta > xdp->data); |
| } |
| |
| static inline bool xdp_metalen_invalid(unsigned long metalen) |
| { |
| return (metalen & (sizeof(__u32) - 1)) || (metalen > 32); |
| } |
| |
| struct xdp_attachment_info { |
| struct bpf_prog *prog; |
| u32 flags; |
| }; |
| |
| struct netdev_bpf; |
| void xdp_attachment_setup(struct xdp_attachment_info *info, |
| struct netdev_bpf *bpf); |
| |
| #define DEV_MAP_BULK_SIZE XDP_BULK_QUEUE_SIZE |
| |
| #define XDP_METADATA_KFUNC_xxx \ |
| XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_TIMESTAMP, \ |
| bpf_xdp_metadata_rx_timestamp) \ |
| XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_HASH, \ |
| bpf_xdp_metadata_rx_hash) \ |
| |
| enum { |
| #define XDP_METADATA_KFUNC(name, _) name, |
| XDP_METADATA_KFUNC_xxx |
| #undef XDP_METADATA_KFUNC |
| MAX_XDP_METADATA_KFUNC, |
| }; |
| |
| enum xdp_rss_hash_type { |
| /* First part: Individual bits for L3/L4 types */ |
| XDP_RSS_L3_IPV4 = BIT(0), |
| XDP_RSS_L3_IPV6 = BIT(1), |
| |
| /* The fixed (L3) IPv4 and IPv6 headers can both be followed by |
| * variable/dynamic headers, IPv4 called Options and IPv6 called |
| * Extension Headers. HW RSS type can contain this info. |
| */ |
| XDP_RSS_L3_DYNHDR = BIT(2), |
| |
| /* When RSS hash covers L4 then drivers MUST set XDP_RSS_L4 bit in |
| * addition to the protocol specific bit. This ease interaction with |
| * SKBs and avoids reserving a fixed mask for future L4 protocol bits. |
| */ |
| XDP_RSS_L4 = BIT(3), /* L4 based hash, proto can be unknown */ |
| XDP_RSS_L4_TCP = BIT(4), |
| XDP_RSS_L4_UDP = BIT(5), |
| XDP_RSS_L4_SCTP = BIT(6), |
| XDP_RSS_L4_IPSEC = BIT(7), /* L4 based hash include IPSEC SPI */ |
| |
| /* Second part: RSS hash type combinations used for driver HW mapping */ |
| XDP_RSS_TYPE_NONE = 0, |
| XDP_RSS_TYPE_L2 = XDP_RSS_TYPE_NONE, |
| |
| XDP_RSS_TYPE_L3_IPV4 = XDP_RSS_L3_IPV4, |
| XDP_RSS_TYPE_L3_IPV6 = XDP_RSS_L3_IPV6, |
| XDP_RSS_TYPE_L3_IPV4_OPT = XDP_RSS_L3_IPV4 | XDP_RSS_L3_DYNHDR, |
| XDP_RSS_TYPE_L3_IPV6_EX = XDP_RSS_L3_IPV6 | XDP_RSS_L3_DYNHDR, |
| |
| XDP_RSS_TYPE_L4_ANY = XDP_RSS_L4, |
| XDP_RSS_TYPE_L4_IPV4_TCP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_TCP, |
| XDP_RSS_TYPE_L4_IPV4_UDP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_UDP, |
| XDP_RSS_TYPE_L4_IPV4_SCTP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_SCTP, |
| XDP_RSS_TYPE_L4_IPV4_IPSEC = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC, |
| |
| XDP_RSS_TYPE_L4_IPV6_TCP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_TCP, |
| XDP_RSS_TYPE_L4_IPV6_UDP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_UDP, |
| XDP_RSS_TYPE_L4_IPV6_SCTP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_SCTP, |
| XDP_RSS_TYPE_L4_IPV6_IPSEC = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC, |
| |
| XDP_RSS_TYPE_L4_IPV6_TCP_EX = XDP_RSS_TYPE_L4_IPV6_TCP | XDP_RSS_L3_DYNHDR, |
| XDP_RSS_TYPE_L4_IPV6_UDP_EX = XDP_RSS_TYPE_L4_IPV6_UDP | XDP_RSS_L3_DYNHDR, |
| XDP_RSS_TYPE_L4_IPV6_SCTP_EX = XDP_RSS_TYPE_L4_IPV6_SCTP | XDP_RSS_L3_DYNHDR, |
| }; |
| |
| #ifdef CONFIG_NET |
| u32 bpf_xdp_metadata_kfunc_id(int id); |
| bool bpf_dev_bound_kfunc_id(u32 btf_id); |
| void xdp_set_features_flag(struct net_device *dev, xdp_features_t val); |
| void xdp_features_set_redirect_target(struct net_device *dev, bool support_sg); |
| void xdp_features_clear_redirect_target(struct net_device *dev); |
| #else |
| static inline u32 bpf_xdp_metadata_kfunc_id(int id) { return 0; } |
| static inline bool bpf_dev_bound_kfunc_id(u32 btf_id) { return false; } |
| |
| static inline void |
| xdp_set_features_flag(struct net_device *dev, xdp_features_t val) |
| { |
| } |
| |
| static inline void |
| xdp_features_set_redirect_target(struct net_device *dev, bool support_sg) |
| { |
| } |
| |
| static inline void |
| xdp_features_clear_redirect_target(struct net_device *dev) |
| { |
| } |
| #endif |
| |
| static inline void xdp_clear_features_flag(struct net_device *dev) |
| { |
| xdp_set_features_flag(dev, 0); |
| } |
| |
| #endif /* __LINUX_NET_XDP_H__ */ |