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 <linux/bpf.h> 11 #include <net/xdp.h> 12 13 struct xsk_buff_pool; 14 struct xdp_rxq_info; 15 struct xsk_queue; 16 struct xdp_desc; 17 struct xdp_umem; 18 struct xdp_sock; 19 struct device; 20 struct page; 21 22 struct xdp_buff_xsk { 23 struct xdp_buff xdp; 24 dma_addr_t dma; 25 dma_addr_t frame_dma; 26 struct xsk_buff_pool *pool; 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 chunk_shift; 71 u32 frame_len; 72 u8 cached_need_wakeup; 73 bool uses_need_wakeup; 74 bool dma_need_sync; 75 bool unaligned; 76 void *addrs; 77 /* Mutual exclusion of the completion ring in the SKB mode. Two cases to protect: 78 * NAPI TX thread and sendmsg error paths in the SKB destructor callback and when 79 * sockets share a single cq when the same netdev and queue id is shared. 80 */ 81 spinlock_t cq_lock; 82 struct xdp_buff_xsk *free_heads[]; 83 }; 84 85 /* Masks for xdp_umem_page flags. 86 * The low 12-bits of the addr will be 0 since this is the page address, so we 87 * can use them for flags. 88 */ 89 #define XSK_NEXT_PG_CONTIG_SHIFT 0 90 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 91 92 /* AF_XDP core. */ 93 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, 94 struct xdp_umem *umem); 95 int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev, 96 u16 queue_id, u16 flags); 97 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_umem *umem, 98 struct net_device *dev, u16 queue_id); 99 void xp_destroy(struct xsk_buff_pool *pool); 100 void xp_get_pool(struct xsk_buff_pool *pool); 101 bool xp_put_pool(struct xsk_buff_pool *pool); 102 void xp_clear_dev(struct xsk_buff_pool *pool); 103 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 104 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 105 106 /* AF_XDP, and XDP core. */ 107 void xp_free(struct xdp_buff_xsk *xskb); 108 109 static inline void xp_init_xskb_addr(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, 110 u64 addr) 111 { 112 xskb->orig_addr = addr; 113 xskb->xdp.data_hard_start = pool->addrs + addr + pool->headroom; 114 } 115 116 static inline void xp_init_xskb_dma(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, 117 dma_addr_t *dma_pages, u64 addr) 118 { 119 xskb->frame_dma = (dma_pages[addr >> PAGE_SHIFT] & ~XSK_NEXT_PG_CONTIG_MASK) + 120 (addr & ~PAGE_MASK); 121 xskb->dma = xskb->frame_dma + pool->headroom + XDP_PACKET_HEADROOM; 122 } 123 124 /* AF_XDP ZC drivers, via xdp_sock_buff.h */ 125 void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq); 126 int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, 127 unsigned long attrs, struct page **pages, u32 nr_pages); 128 void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs); 129 struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool); 130 u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max); 131 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count); 132 void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr); 133 dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr); 134 static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb) 135 { 136 return xskb->dma; 137 } 138 139 static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb) 140 { 141 return xskb->frame_dma; 142 } 143 144 void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb); 145 static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb) 146 { 147 xp_dma_sync_for_cpu_slow(xskb); 148 } 149 150 void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma, 151 size_t size); 152 static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool, 153 dma_addr_t dma, size_t size) 154 { 155 if (!pool->dma_need_sync) 156 return; 157 158 xp_dma_sync_for_device_slow(pool, dma, size); 159 } 160 161 /* Masks for xdp_umem_page flags. 162 * The low 12-bits of the addr will be 0 since this is the page address, so we 163 * can use them for flags. 164 */ 165 #define XSK_NEXT_PG_CONTIG_SHIFT 0 166 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 167 168 static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, 169 u64 addr, u32 len) 170 { 171 bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE; 172 173 if (likely(!cross_pg)) 174 return false; 175 176 if (pool->dma_pages_cnt) { 177 return !(pool->dma_pages[addr >> PAGE_SHIFT] & 178 XSK_NEXT_PG_CONTIG_MASK); 179 } 180 181 /* skb path */ 182 return addr + len > pool->addrs_cnt; 183 } 184 185 static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr) 186 { 187 return addr & pool->chunk_mask; 188 } 189 190 static inline u64 xp_unaligned_extract_addr(u64 addr) 191 { 192 return addr & XSK_UNALIGNED_BUF_ADDR_MASK; 193 } 194 195 static inline u64 xp_unaligned_extract_offset(u64 addr) 196 { 197 return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT; 198 } 199 200 static inline u64 xp_unaligned_add_offset_to_addr(u64 addr) 201 { 202 return xp_unaligned_extract_addr(addr) + 203 xp_unaligned_extract_offset(addr); 204 } 205 206 static inline u32 xp_aligned_extract_idx(struct xsk_buff_pool *pool, u64 addr) 207 { 208 return xp_aligned_extract_addr(pool, addr) >> pool->chunk_shift; 209 } 210 211 static inline void xp_release(struct xdp_buff_xsk *xskb) 212 { 213 if (xskb->pool->unaligned) 214 xskb->pool->free_heads[xskb->pool->free_heads_cnt++] = xskb; 215 } 216 217 static inline u64 xp_get_handle(struct xdp_buff_xsk *xskb) 218 { 219 u64 offset = xskb->xdp.data - xskb->xdp.data_hard_start; 220 221 offset += xskb->pool->headroom; 222 if (!xskb->pool->unaligned) 223 return xskb->orig_addr + offset; 224 return xskb->orig_addr + (offset << XSK_UNALIGNED_BUF_OFFSET_SHIFT); 225 } 226 227 #endif /* XSK_BUFF_POOL_H_ */ 228