diff options
Diffstat (limited to 'include/net/xdp.h')
-rw-r--r-- | include/net/xdp.h | 286 |
1 files changed, 257 insertions, 29 deletions
diff --git a/include/net/xdp.h b/include/net/xdp.h index 40c6d3398458..55dbc68bfffc 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -6,6 +6,8 @@ #ifndef __LINUX_NET_XDP_H__ #define __LINUX_NET_XDP_H__ +#include <linux/skbuff.h> /* skb_shared_info */ + /** * DOC: XDP RX-queue information * @@ -13,13 +15,13 @@ * 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 carry a (pointer) + * 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 is read-mostly and must not be updated during + * 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. @@ -28,8 +30,8 @@ * 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 unregistor (which - * also apply for driver shutdown and unload). The register API is + * 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. */ @@ -37,7 +39,7 @@ 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_ZERO_COPY, + MEM_TYPE_XSK_BUFF_POOL, MEM_TYPE_MAX, }; @@ -52,36 +54,162 @@ struct xdp_mem_info { struct page_pool; -struct zero_copy_allocator { - void (*free)(struct zero_copy_allocator *zca, unsigned long handle); -}; - 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; - unsigned long handle; 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; - u16 metasize; + 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 */ @@ -91,33 +219,85 @@ static inline void xdp_scrub_frame(struct xdp_frame *frame) 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); -/* Convert xdp_buff to xdp_frame */ static inline -struct xdp_frame *convert_to_xdp_frame(struct xdp_buff *xdp) +void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp) { - struct xdp_frame *xdp_frame; - int metasize; - int headroom; + 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; +} - if (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY) - return xdp_convert_zc_to_xdp_frame(xdp); +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 NULL; + return -ENOSPC; - /* Store info in top of packet */ - xdp_frame = xdp->data_hard_start; + /* 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; @@ -125,9 +305,14 @@ struct xdp_frame *convert_to_xdp_frame(struct xdp_buff *xdp) 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 @@ -138,20 +323,60 @@ 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) - __xdp_release_frame(xdpf->data, mem); + 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); } -int xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq, - struct net_device *dev, u32 queue_index); 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. @@ -168,17 +393,20 @@ 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; -int xdp_attachment_query(struct xdp_attachment_info *info, - struct netdev_bpf *bpf); -bool xdp_attachment_flags_ok(struct xdp_attachment_info *info, - struct netdev_bpf *bpf); void xdp_attachment_setup(struct xdp_attachment_info *info, struct netdev_bpf *bpf); +#define DEV_MAP_BULK_SIZE XDP_BULK_QUEUE_SIZE + #endif /* __LINUX_NET_XDP_H__ */ |