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 bool unaligned; 27 u64 orig_addr; 28 struct list_head free_list_node; 29 }; 30 31 struct xsk_dma_map { 32 dma_addr_t *dma_pages; 33 struct device *dev; 34 struct net_device *netdev; 35 refcount_t users; 36 struct list_head list; /* Protected by the RTNL_LOCK */ 37 u32 dma_pages_cnt; 38 bool dma_need_sync; 39 }; 40 41 struct xsk_buff_pool { 42 /* Members only used in the control path first. */ 43 struct device *dev; 44 struct net_device *netdev; 45 struct list_head xsk_tx_list; 46 /* Protects modifications to the xsk_tx_list */ 47 spinlock_t xsk_tx_list_lock; 48 refcount_t users; 49 struct xdp_umem *umem; 50 struct work_struct work; 51 struct list_head free_list; 52 u32 heads_cnt; 53 u16 queue_id; 54 55 /* Data path members as close to free_heads at the end as possible. */ 56 struct xsk_queue *fq ____cacheline_aligned_in_smp; 57 struct xsk_queue *cq; 58 /* For performance reasons, each buff pool has its own array of dma_pages 59 * even when they are identical. 60 */ 61 dma_addr_t *dma_pages; 62 struct xdp_buff_xsk *heads; 63 u64 chunk_mask; 64 u64 addrs_cnt; 65 u32 free_list_cnt; 66 u32 dma_pages_cnt; 67 u32 free_heads_cnt; 68 u32 headroom; 69 u32 chunk_size; 70 u32 frame_len; 71 u8 cached_need_wakeup; 72 bool uses_need_wakeup; 73 bool dma_need_sync; 74 bool unaligned; 75 void *addrs; 76 /* Mutual exclusion of the completion ring in the SKB mode. Two cases to protect: 77 * NAPI TX thread and sendmsg error paths in the SKB destructor callback and when 78 * sockets share a single cq when the same netdev and queue id is shared. 79 */ 80 spinlock_t cq_lock; 81 struct xdp_buff_xsk *free_heads[]; 82 }; 83 84 /* AF_XDP core. */ 85 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, 86 struct xdp_umem *umem); 87 int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev, 88 u16 queue_id, u16 flags); 89 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_umem *umem, 90 struct net_device *dev, u16 queue_id); 91 void xp_destroy(struct xsk_buff_pool *pool); 92 void xp_release(struct xdp_buff_xsk *xskb); 93 void xp_get_pool(struct xsk_buff_pool *pool); 94 bool xp_put_pool(struct xsk_buff_pool *pool); 95 void xp_clear_dev(struct xsk_buff_pool *pool); 96 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 97 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 98 99 /* AF_XDP, and XDP core. */ 100 void xp_free(struct xdp_buff_xsk *xskb); 101 102 /* AF_XDP ZC drivers, via xdp_sock_buff.h */ 103 void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq); 104 int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, 105 unsigned long attrs, struct page **pages, u32 nr_pages); 106 void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs); 107 struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool); 108 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count); 109 void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr); 110 dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr); 111 static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb) 112 { 113 return xskb->dma; 114 } 115 116 static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb) 117 { 118 return xskb->frame_dma; 119 } 120 121 void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb); 122 static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb) 123 { 124 xp_dma_sync_for_cpu_slow(xskb); 125 } 126 127 void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma, 128 size_t size); 129 static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool, 130 dma_addr_t dma, size_t size) 131 { 132 if (!pool->dma_need_sync) 133 return; 134 135 xp_dma_sync_for_device_slow(pool, dma, size); 136 } 137 138 /* Masks for xdp_umem_page flags. 139 * The low 12-bits of the addr will be 0 since this is the page address, so we 140 * can use them for flags. 141 */ 142 #define XSK_NEXT_PG_CONTIG_SHIFT 0 143 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 144 145 static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, 146 u64 addr, u32 len) 147 { 148 bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE; 149 150 if (likely(!cross_pg)) 151 return false; 152 153 if (pool->dma_pages_cnt) { 154 return !(pool->dma_pages[addr >> PAGE_SHIFT] & 155 XSK_NEXT_PG_CONTIG_MASK); 156 } 157 158 /* skb path */ 159 return addr + len > pool->addrs_cnt; 160 } 161 162 static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr) 163 { 164 return addr & pool->chunk_mask; 165 } 166 167 static inline u64 xp_unaligned_extract_addr(u64 addr) 168 { 169 return addr & XSK_UNALIGNED_BUF_ADDR_MASK; 170 } 171 172 static inline u64 xp_unaligned_extract_offset(u64 addr) 173 { 174 return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT; 175 } 176 177 static inline u64 xp_unaligned_add_offset_to_addr(u64 addr) 178 { 179 return xp_unaligned_extract_addr(addr) + 180 xp_unaligned_extract_offset(addr); 181 } 182 183 #endif /* XSK_BUFF_POOL_H_ */ 184