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