diff options
Diffstat (limited to 'include/net/xsk_buff_pool.h')
| -rw-r--r-- | include/net/xsk_buff_pool.h | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/include/net/xsk_buff_pool.h b/include/net/xsk_buff_pool.h new file mode 100644 index 000000000..b0bdff26f --- /dev/null +++ b/include/net/xsk_buff_pool.h @@ -0,0 +1,236 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright(c) 2020 Intel Corporation. */ + +#ifndef XSK_BUFF_POOL_H_ +#define XSK_BUFF_POOL_H_ + +#include <linux/if_xdp.h> +#include <linux/types.h> +#include <linux/dma-mapping.h> +#include <linux/bpf.h> +#include <net/xdp.h> + +struct xsk_buff_pool; +struct xdp_rxq_info; +struct xsk_queue; +struct xdp_desc; +struct xdp_umem; +struct xdp_sock; +struct device; +struct page; + +#define XSK_PRIV_MAX 24 + +struct xdp_buff_xsk { + struct xdp_buff xdp; + u8 cb[XSK_PRIV_MAX]; + dma_addr_t dma; + dma_addr_t frame_dma; + struct xsk_buff_pool *pool; + u64 orig_addr; + struct list_head free_list_node; + struct list_head xskb_list_node; +}; + +#define XSK_CHECK_PRIV_TYPE(t) BUILD_BUG_ON(sizeof(t) > offsetofend(struct xdp_buff_xsk, cb)) + +struct xsk_dma_map { + dma_addr_t *dma_pages; + struct device *dev; + struct net_device *netdev; + refcount_t users; + struct list_head list; /* Protected by the RTNL_LOCK */ + u32 dma_pages_cnt; + bool dma_need_sync; +}; + +struct xsk_buff_pool { + /* Members only used in the control path first. */ + struct device *dev; + struct net_device *netdev; + struct list_head xsk_tx_list; + /* Protects modifications to the xsk_tx_list */ + spinlock_t xsk_tx_list_lock; + refcount_t users; + struct xdp_umem *umem; + struct work_struct work; + struct list_head free_list; + struct list_head xskb_list; + u32 heads_cnt; + u16 queue_id; + + /* Data path members as close to free_heads at the end as possible. */ + struct xsk_queue *fq ____cacheline_aligned_in_smp; + struct xsk_queue *cq; + /* For performance reasons, each buff pool has its own array of dma_pages + * even when they are identical. + */ + dma_addr_t *dma_pages; + struct xdp_buff_xsk *heads; + struct xdp_desc *tx_descs; + u64 chunk_mask; + u64 addrs_cnt; + u32 free_list_cnt; + u32 dma_pages_cnt; + u32 free_heads_cnt; + u32 headroom; + u32 chunk_size; + u32 chunk_shift; + u32 frame_len; + u8 cached_need_wakeup; + bool uses_need_wakeup; + bool dma_need_sync; + bool unaligned; + void *addrs; + /* Mutual exclusion of the completion ring in the SKB mode. Two cases to protect: + * NAPI TX thread and sendmsg error paths in the SKB destructor callback and when + * sockets share a single cq when the same netdev and queue id is shared. + */ + spinlock_t cq_lock; + struct xdp_buff_xsk *free_heads[]; +}; + +/* Masks for xdp_umem_page flags. + * The low 12-bits of the addr will be 0 since this is the page address, so we + * can use them for flags. + */ +#define XSK_NEXT_PG_CONTIG_SHIFT 0 +#define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) + +/* AF_XDP core. */ +struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, + struct xdp_umem *umem); +int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev, + u16 queue_id, u16 flags); +int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs, + struct net_device *dev, u16 queue_id); +int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs); +void xp_destroy(struct xsk_buff_pool *pool); +void xp_get_pool(struct xsk_buff_pool *pool); +bool xp_put_pool(struct xsk_buff_pool *pool); +void xp_clear_dev(struct xsk_buff_pool *pool); +void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); +void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); + +/* AF_XDP, and XDP core. */ +void xp_free(struct xdp_buff_xsk *xskb); + +static inline void xp_init_xskb_addr(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, + u64 addr) +{ + xskb->orig_addr = addr; + xskb->xdp.data_hard_start = pool->addrs + addr + pool->headroom; +} + +static inline void xp_init_xskb_dma(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, + dma_addr_t *dma_pages, u64 addr) +{ + xskb->frame_dma = (dma_pages[addr >> PAGE_SHIFT] & ~XSK_NEXT_PG_CONTIG_MASK) + + (addr & ~PAGE_MASK); + xskb->dma = xskb->frame_dma + pool->headroom + XDP_PACKET_HEADROOM; +} + +/* AF_XDP ZC drivers, via xdp_sock_buff.h */ +void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq); +int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, + unsigned long attrs, struct page **pages, u32 nr_pages); +void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs); +struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool); +u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max); +bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count); +void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr); +dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr); +static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb) +{ + return xskb->dma; +} + +static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb) +{ + return xskb->frame_dma; +} + +void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb); +static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb) +{ + xp_dma_sync_for_cpu_slow(xskb); +} + +void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma, + size_t size); +static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool, + dma_addr_t dma, size_t size) +{ + if (!pool->dma_need_sync) + return; + + xp_dma_sync_for_device_slow(pool, dma, size); +} + +/* Masks for xdp_umem_page flags. + * The low 12-bits of the addr will be 0 since this is the page address, so we + * can use them for flags. + */ +#define XSK_NEXT_PG_CONTIG_SHIFT 0 +#define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) + +static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, + u64 addr, u32 len) +{ + bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE; + + if (likely(!cross_pg)) + return false; + + return pool->dma_pages && + !(pool->dma_pages[addr >> PAGE_SHIFT] & XSK_NEXT_PG_CONTIG_MASK); +} + +static inline bool xp_mb_desc(struct xdp_desc *desc) +{ + return desc->options & XDP_PKT_CONTD; +} + +static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr) +{ + return addr & pool->chunk_mask; +} + +static inline u64 xp_unaligned_extract_addr(u64 addr) +{ + return addr & XSK_UNALIGNED_BUF_ADDR_MASK; +} + +static inline u64 xp_unaligned_extract_offset(u64 addr) +{ + return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT; +} + +static inline u64 xp_unaligned_add_offset_to_addr(u64 addr) +{ + return xp_unaligned_extract_addr(addr) + + xp_unaligned_extract_offset(addr); +} + +static inline u32 xp_aligned_extract_idx(struct xsk_buff_pool *pool, u64 addr) +{ + return xp_aligned_extract_addr(pool, addr) >> pool->chunk_shift; +} + +static inline void xp_release(struct xdp_buff_xsk *xskb) +{ + if (xskb->pool->unaligned) + xskb->pool->free_heads[xskb->pool->free_heads_cnt++] = xskb; +} + +static inline u64 xp_get_handle(struct xdp_buff_xsk *xskb) +{ + u64 offset = xskb->xdp.data - xskb->xdp.data_hard_start; + + offset += xskb->pool->headroom; + if (!xskb->pool->unaligned) + return xskb->orig_addr + offset; + return xskb->orig_addr + (offset << XSK_UNALIGNED_BUF_OFFSET_SHIFT); +} + +#endif /* XSK_BUFF_POOL_H_ */ |