1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Copyright(c) 2020 Intel Corporation. */ 3 4 #ifndef XSK_BUFF_POOL_H_ 5 #define XSK_BUFF_POOL_H_ 6 7 #include <linux/if_xdp.h> 8 #include <linux/types.h> 9 #include <linux/dma-mapping.h> 10 #include <net/xdp.h> 11 12 struct xsk_buff_pool; 13 struct xdp_rxq_info; 14 struct xsk_queue; 15 struct xdp_desc; 16 struct xdp_umem; 17 struct xdp_sock; 18 struct device; 19 struct page; 20 21 struct xdp_buff_xsk { 22 struct xdp_buff xdp; 23 dma_addr_t dma; 24 dma_addr_t frame_dma; 25 struct xsk_buff_pool *pool; 26 u64 orig_addr; 27 struct list_head free_list_node; 28 }; 29 30 struct xsk_dma_map { 31 dma_addr_t *dma_pages; 32 struct device *dev; 33 struct net_device *netdev; 34 refcount_t users; 35 struct list_head list; /* Protected by the RTNL_LOCK */ 36 u32 dma_pages_cnt; 37 bool dma_need_sync; 38 }; 39 40 struct xsk_buff_pool { 41 /* Members only used in the control path first. */ 42 struct device *dev; 43 struct net_device *netdev; 44 struct list_head xsk_tx_list; 45 /* Protects modifications to the xsk_tx_list */ 46 spinlock_t xsk_tx_list_lock; 47 refcount_t users; 48 struct xdp_umem *umem; 49 struct work_struct work; 50 struct list_head free_list; 51 u32 heads_cnt; 52 u16 queue_id; 53 54 /* Data path members as close to free_heads at the end as possible. */ 55 struct xsk_queue *fq ____cacheline_aligned_in_smp; 56 struct xsk_queue *cq; 57 /* For performance reasons, each buff pool has its own array of dma_pages 58 * even when they are identical. 59 */ 60 dma_addr_t *dma_pages; 61 struct xdp_buff_xsk *heads; 62 u64 chunk_mask; 63 u64 addrs_cnt; 64 u32 free_list_cnt; 65 u32 dma_pages_cnt; 66 u32 free_heads_cnt; 67 u32 headroom; 68 u32 chunk_size; 69 u32 frame_len; 70 u8 cached_need_wakeup; 71 bool uses_need_wakeup; 72 bool dma_need_sync; 73 bool unaligned; 74 void *addrs; 75 /* Mutual exclusion of the completion ring in the SKB mode. Two cases to protect: 76 * NAPI TX thread and sendmsg error paths in the SKB destructor callback and when 77 * sockets share a single cq when the same netdev and queue id is shared. 78 */ 79 spinlock_t cq_lock; 80 struct xdp_buff_xsk *free_heads[]; 81 }; 82 83 /* AF_XDP core. */ 84 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, 85 struct xdp_umem *umem); 86 int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev, 87 u16 queue_id, u16 flags); 88 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_umem *umem, 89 struct net_device *dev, u16 queue_id); 90 void xp_destroy(struct xsk_buff_pool *pool); 91 void xp_release(struct xdp_buff_xsk *xskb); 92 void xp_get_pool(struct xsk_buff_pool *pool); 93 bool xp_put_pool(struct xsk_buff_pool *pool); 94 void xp_clear_dev(struct xsk_buff_pool *pool); 95 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 96 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 97 98 /* AF_XDP, and XDP core. */ 99 void xp_free(struct xdp_buff_xsk *xskb); 100 101 /* AF_XDP ZC drivers, via xdp_sock_buff.h */ 102 void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq); 103 int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, 104 unsigned long attrs, struct page **pages, u32 nr_pages); 105 void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs); 106 struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool); 107 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count); 108 void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr); 109 dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr); 110 static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb) 111 { 112 return xskb->dma; 113 } 114 115 static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb) 116 { 117 return xskb->frame_dma; 118 } 119 120 void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb); 121 static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb) 122 { 123 xp_dma_sync_for_cpu_slow(xskb); 124 } 125 126 void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma, 127 size_t size); 128 static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool, 129 dma_addr_t dma, size_t size) 130 { 131 if (!pool->dma_need_sync) 132 return; 133 134 xp_dma_sync_for_device_slow(pool, dma, size); 135 } 136 137 /* Masks for xdp_umem_page flags. 138 * The low 12-bits of the addr will be 0 since this is the page address, so we 139 * can use them for flags. 140 */ 141 #define XSK_NEXT_PG_CONTIG_SHIFT 0 142 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 143 144 static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, 145 u64 addr, u32 len) 146 { 147 bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE; 148 149 if (likely(!cross_pg)) 150 return false; 151 152 if (pool->dma_pages_cnt) { 153 return !(pool->dma_pages[addr >> PAGE_SHIFT] & 154 XSK_NEXT_PG_CONTIG_MASK); 155 } 156 157 /* skb path */ 158 return addr + len > pool->addrs_cnt; 159 } 160 161 static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr) 162 { 163 return addr & pool->chunk_mask; 164 } 165 166 static inline u64 xp_unaligned_extract_addr(u64 addr) 167 { 168 return addr & XSK_UNALIGNED_BUF_ADDR_MASK; 169 } 170 171 static inline u64 xp_unaligned_extract_offset(u64 addr) 172 { 173 return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT; 174 } 175 176 static inline u64 xp_unaligned_add_offset_to_addr(u64 addr) 177 { 178 return xp_unaligned_extract_addr(addr) + 179 xp_unaligned_extract_offset(addr); 180 } 181 182 #endif /* XSK_BUFF_POOL_H_ */ 183