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_cb_desc; 16 struct xsk_queue; 17 struct xdp_desc; 18 struct xdp_umem; 19 struct xdp_sock; 20 struct device; 21 struct page; 22 23 #define XSK_PRIV_MAX 24 24 25 struct xdp_buff_xsk { 26 struct xdp_buff xdp; 27 u8 cb[XSK_PRIV_MAX]; 28 dma_addr_t dma; 29 dma_addr_t frame_dma; 30 struct xsk_buff_pool *pool; 31 struct list_head list_node; 32 } __aligned_largest; 33 34 #define XSK_CHECK_PRIV_TYPE(t) BUILD_BUG_ON(sizeof(t) > offsetofend(struct xdp_buff_xsk, cb)) 35 #define XSK_TX_COMPL_FITS(t) BUILD_BUG_ON(sizeof(struct xsk_tx_metadata_compl) > sizeof(t)) 36 37 struct xsk_dma_map { 38 dma_addr_t *dma_pages; 39 struct device *dev; 40 struct net_device *netdev; 41 refcount_t users; 42 struct list_head list; /* Protected by the RTNL_LOCK */ 43 u32 dma_pages_cnt; 44 }; 45 46 struct xsk_buff_pool { 47 /* Members only used in the control path first. */ 48 struct device *dev; 49 struct net_device *netdev; 50 struct list_head xsk_tx_list; 51 /* Assigned pools, including deferred releases; ops protected. */ 52 struct hlist_node dev_node; 53 /* Protects modifications to the xsk_tx_list */ 54 spinlock_t xsk_tx_list_lock; 55 refcount_t users; 56 struct xdp_umem *umem; 57 struct work_struct work; 58 /* Protects generic receive in shared and non-shared umem mode. */ 59 spinlock_t rx_lock; 60 struct list_head free_list; 61 struct list_head xskb_list; 62 u32 heads_cnt; 63 u16 queue_id; 64 65 /* Data path members as close to free_heads at the end as possible. */ 66 struct xsk_queue *fq ____cacheline_aligned_in_smp; 67 struct xsk_queue *cq; 68 /* For performance reasons, each buff pool has its own array of dma_pages 69 * even when they are identical. 70 */ 71 dma_addr_t *dma_pages; 72 struct xdp_buff_xsk *heads; 73 struct xdp_desc *tx_descs; 74 u64 chunk_mask; 75 u64 addrs_cnt; 76 u32 free_list_cnt; 77 u32 dma_pages_cnt; 78 u32 free_heads_cnt; 79 u32 headroom; 80 u32 chunk_size; 81 u32 chunk_shift; 82 u32 frame_len; 83 u32 tx_descs_nentries; 84 u32 reclaim_descs; 85 u32 tx_zc_pending_descs; 86 u32 xdp_zc_max_segs; 87 u8 tx_metadata_len; /* inherited from umem */ 88 u8 cached_need_wakeup; 89 bool uses_need_wakeup; 90 bool unaligned; 91 bool tx_sw_csum; 92 void *addrs; 93 /* Mutual exclusion of the completion ring in the SKB mode. 94 * Protect: NAPI TX thread and sendmsg error paths in the SKB 95 * destructor callback. 96 */ 97 spinlock_t cq_prod_lock; 98 struct xdp_buff_xsk *free_heads[]; 99 }; 100 101 /* Masks for xdp_umem_page flags. 102 * The low 12-bits of the addr will be 0 since this is the page address, so we 103 * can use them for flags. 104 */ 105 #define XSK_NEXT_PG_CONTIG_SHIFT 0 106 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 107 108 /* AF_XDP core. */ 109 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, 110 struct xdp_umem *umem, 111 u32 max_segs); 112 int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev, 113 u16 queue_id, u16 flags); 114 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs, 115 struct net_device *dev, u16 queue_id); 116 int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs, 117 u32 max_segs); 118 void xp_destroy(struct xsk_buff_pool *pool); 119 void xp_get_pool(struct xsk_buff_pool *pool); 120 bool xp_put_pool(struct xsk_buff_pool *pool); 121 void xp_clear_dev(struct xsk_buff_pool *pool); 122 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 123 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 124 void xp_clear_dev_all(struct net_device *dev); 125 126 /* AF_XDP, and XDP core. */ 127 void xp_free(struct xdp_buff_xsk *xskb); 128 129 static inline void xp_init_xskb_addr(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, 130 u64 addr) 131 { 132 xskb->xdp.data_hard_start = pool->addrs + addr + pool->headroom; 133 } 134 135 static inline void xp_init_xskb_dma(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, 136 dma_addr_t *dma_pages, u64 addr) 137 { 138 xskb->frame_dma = (dma_pages[addr >> PAGE_SHIFT] & ~XSK_NEXT_PG_CONTIG_MASK) + 139 (addr & ~PAGE_MASK); 140 xskb->dma = xskb->frame_dma + pool->headroom + XDP_PACKET_HEADROOM; 141 } 142 143 /* AF_XDP ZC drivers, via xdp_sock_buff.h */ 144 void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq); 145 void xp_fill_cb(struct xsk_buff_pool *pool, struct xsk_cb_desc *desc); 146 int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, 147 unsigned long attrs, struct page **pages, u32 nr_pages); 148 void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs); 149 struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool); 150 u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max); 151 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count); 152 void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr); 153 dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr); 154 155 struct xdp_desc_ctx { 156 dma_addr_t dma; 157 struct xsk_tx_metadata *meta; 158 }; 159 160 struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr, 161 u32 options); 162 163 static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb) 164 { 165 return xskb->dma; 166 } 167 168 static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb) 169 { 170 return xskb->frame_dma; 171 } 172 173 static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb) 174 { 175 dma_sync_single_for_cpu(xskb->pool->dev, xskb->dma, 176 xskb->pool->frame_len, 177 DMA_BIDIRECTIONAL); 178 } 179 180 static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool, 181 dma_addr_t dma, size_t size) 182 { 183 dma_sync_single_for_device(pool->dev, dma, size, DMA_BIDIRECTIONAL); 184 } 185 186 static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, 187 u64 addr, u32 len) 188 { 189 bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE; 190 191 if (likely(!cross_pg)) 192 return false; 193 194 return pool->dma_pages && 195 !(pool->dma_pages[addr >> PAGE_SHIFT] & XSK_NEXT_PG_CONTIG_MASK); 196 } 197 198 static inline bool xp_mb_desc(const struct xdp_desc *desc) 199 { 200 return desc->options & XDP_PKT_CONTD; 201 } 202 203 static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr) 204 { 205 return addr & pool->chunk_mask; 206 } 207 208 static inline u64 xp_unaligned_extract_addr(u64 addr) 209 { 210 return addr & XSK_UNALIGNED_BUF_ADDR_MASK; 211 } 212 213 static inline u64 xp_unaligned_extract_offset(u64 addr) 214 { 215 return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT; 216 } 217 218 static inline u64 xp_unaligned_add_offset_to_addr(u64 addr) 219 { 220 return xp_unaligned_extract_addr(addr) + 221 xp_unaligned_extract_offset(addr); 222 } 223 224 static inline u32 xp_aligned_extract_idx(struct xsk_buff_pool *pool, u64 addr) 225 { 226 return xp_aligned_extract_addr(pool, addr) >> pool->chunk_shift; 227 } 228 229 static inline void xp_release(struct xdp_buff_xsk *xskb) 230 { 231 if (xskb->pool->unaligned) 232 xskb->pool->free_heads[xskb->pool->free_heads_cnt++] = xskb; 233 } 234 235 static inline u64 xp_get_handle(struct xdp_buff_xsk *xskb, 236 struct xsk_buff_pool *pool) 237 { 238 u64 orig_addr = xskb->xdp.data - pool->addrs; 239 u64 offset; 240 241 if (!pool->unaligned) 242 return orig_addr; 243 244 offset = xskb->xdp.data - xskb->xdp.data_hard_start; 245 offset += pool->headroom; 246 orig_addr -= offset; 247 return orig_addr + (offset << XSK_UNALIGNED_BUF_OFFSET_SHIFT); 248 } 249 250 static inline bool xp_tx_metadata_enabled(const struct xsk_buff_pool *pool) 251 { 252 return pool->tx_metadata_len > 0; 253 } 254 255 #endif /* XSK_BUFF_POOL_H_ */ 256