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 u64 orig_addr; 32 struct list_head free_list_node; 33 struct list_head xskb_list_node; 34 }; 35 36 #define XSK_CHECK_PRIV_TYPE(t) BUILD_BUG_ON(sizeof(t) > offsetofend(struct xdp_buff_xsk, cb)) 37 #define XSK_TX_COMPL_FITS(t) BUILD_BUG_ON(sizeof(struct xsk_tx_metadata_compl) > sizeof(t)) 38 39 struct xsk_dma_map { 40 dma_addr_t *dma_pages; 41 struct device *dev; 42 struct net_device *netdev; 43 refcount_t users; 44 struct list_head list; /* Protected by the RTNL_LOCK */ 45 u32 dma_pages_cnt; 46 }; 47 48 struct xsk_buff_pool { 49 /* Members only used in the control path first. */ 50 struct device *dev; 51 struct net_device *netdev; 52 struct list_head xsk_tx_list; 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 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 u8 tx_metadata_len; /* inherited from umem */ 82 u8 cached_need_wakeup; 83 bool uses_need_wakeup; 84 bool unaligned; 85 bool tx_sw_csum; 86 void *addrs; 87 /* Mutual exclusion of the completion ring in the SKB mode. Two cases to protect: 88 * NAPI TX thread and sendmsg error paths in the SKB destructor callback and when 89 * sockets share a single cq when the same netdev and queue id is shared. 90 */ 91 spinlock_t cq_lock; 92 struct xdp_buff_xsk *free_heads[]; 93 }; 94 95 /* Masks for xdp_umem_page flags. 96 * The low 12-bits of the addr will be 0 since this is the page address, so we 97 * can use them for flags. 98 */ 99 #define XSK_NEXT_PG_CONTIG_SHIFT 0 100 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 101 102 /* AF_XDP core. */ 103 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, 104 struct xdp_umem *umem); 105 int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev, 106 u16 queue_id, u16 flags); 107 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs, 108 struct net_device *dev, u16 queue_id); 109 int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs); 110 void xp_destroy(struct xsk_buff_pool *pool); 111 void xp_get_pool(struct xsk_buff_pool *pool); 112 bool xp_put_pool(struct xsk_buff_pool *pool); 113 void xp_clear_dev(struct xsk_buff_pool *pool); 114 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 115 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 116 117 /* AF_XDP, and XDP core. */ 118 void xp_free(struct xdp_buff_xsk *xskb); 119 120 static inline void xp_init_xskb_addr(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, 121 u64 addr) 122 { 123 xskb->orig_addr = addr; 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 static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb) 147 { 148 return xskb->dma; 149 } 150 151 static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb) 152 { 153 return xskb->frame_dma; 154 } 155 156 static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb) 157 { 158 dma_sync_single_for_cpu(xskb->pool->dev, xskb->dma, 159 xskb->pool->frame_len, 160 DMA_BIDIRECTIONAL); 161 } 162 163 static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool, 164 dma_addr_t dma, size_t size) 165 { 166 dma_sync_single_for_device(pool->dev, dma, size, DMA_BIDIRECTIONAL); 167 } 168 169 /* Masks for xdp_umem_page flags. 170 * The low 12-bits of the addr will be 0 since this is the page address, so we 171 * can use them for flags. 172 */ 173 #define XSK_NEXT_PG_CONTIG_SHIFT 0 174 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 175 176 static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, 177 u64 addr, u32 len) 178 { 179 bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE; 180 181 if (likely(!cross_pg)) 182 return false; 183 184 return pool->dma_pages && 185 !(pool->dma_pages[addr >> PAGE_SHIFT] & XSK_NEXT_PG_CONTIG_MASK); 186 } 187 188 static inline bool xp_mb_desc(struct xdp_desc *desc) 189 { 190 return desc->options & XDP_PKT_CONTD; 191 } 192 193 static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr) 194 { 195 return addr & pool->chunk_mask; 196 } 197 198 static inline u64 xp_unaligned_extract_addr(u64 addr) 199 { 200 return addr & XSK_UNALIGNED_BUF_ADDR_MASK; 201 } 202 203 static inline u64 xp_unaligned_extract_offset(u64 addr) 204 { 205 return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT; 206 } 207 208 static inline u64 xp_unaligned_add_offset_to_addr(u64 addr) 209 { 210 return xp_unaligned_extract_addr(addr) + 211 xp_unaligned_extract_offset(addr); 212 } 213 214 static inline u32 xp_aligned_extract_idx(struct xsk_buff_pool *pool, u64 addr) 215 { 216 return xp_aligned_extract_addr(pool, addr) >> pool->chunk_shift; 217 } 218 219 static inline void xp_release(struct xdp_buff_xsk *xskb) 220 { 221 if (xskb->pool->unaligned) 222 xskb->pool->free_heads[xskb->pool->free_heads_cnt++] = xskb; 223 } 224 225 static inline u64 xp_get_handle(struct xdp_buff_xsk *xskb) 226 { 227 u64 offset = xskb->xdp.data - xskb->xdp.data_hard_start; 228 229 offset += xskb->pool->headroom; 230 if (!xskb->pool->unaligned) 231 return xskb->orig_addr + offset; 232 return xskb->orig_addr + (offset << XSK_UNALIGNED_BUF_OFFSET_SHIFT); 233 } 234 235 static inline bool xp_tx_metadata_enabled(const struct xsk_buff_pool *pool) 236 { 237 return pool->tx_metadata_len > 0; 238 } 239 240 #endif /* XSK_BUFF_POOL_H_ */ 241