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