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 #define XSK_PRIV_MAX 24 23 24 struct xdp_buff_xsk { 25 struct xdp_buff xdp; 26 u8 cb[XSK_PRIV_MAX]; 27 dma_addr_t dma; 28 dma_addr_t frame_dma; 29 struct xsk_buff_pool *pool; 30 u64 orig_addr; 31 struct list_head free_list_node; 32 }; 33 34 #define XSK_CHECK_PRIV_TYPE(t) BUILD_BUG_ON(sizeof(t) > offsetofend(struct xdp_buff_xsk, cb)) 35 36 struct xsk_dma_map { 37 dma_addr_t *dma_pages; 38 struct device *dev; 39 struct net_device *netdev; 40 refcount_t users; 41 struct list_head list; /* Protected by the RTNL_LOCK */ 42 u32 dma_pages_cnt; 43 bool dma_need_sync; 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 u32 heads_cnt; 58 u16 queue_id; 59 60 /* Data path members as close to free_heads at the end as possible. */ 61 struct xsk_queue *fq ____cacheline_aligned_in_smp; 62 struct xsk_queue *cq; 63 /* For performance reasons, each buff pool has its own array of dma_pages 64 * even when they are identical. 65 */ 66 dma_addr_t *dma_pages; 67 struct xdp_buff_xsk *heads; 68 struct xdp_desc *tx_descs; 69 u64 chunk_mask; 70 u64 addrs_cnt; 71 u32 free_list_cnt; 72 u32 dma_pages_cnt; 73 u32 free_heads_cnt; 74 u32 headroom; 75 u32 chunk_size; 76 u32 chunk_shift; 77 u32 frame_len; 78 u8 cached_need_wakeup; 79 bool uses_need_wakeup; 80 bool dma_need_sync; 81 bool unaligned; 82 void *addrs; 83 /* Mutual exclusion of the completion ring in the SKB mode. Two cases to protect: 84 * NAPI TX thread and sendmsg error paths in the SKB destructor callback and when 85 * sockets share a single cq when the same netdev and queue id is shared. 86 */ 87 spinlock_t cq_lock; 88 struct xdp_buff_xsk *free_heads[]; 89 }; 90 91 /* Masks for xdp_umem_page flags. 92 * The low 12-bits of the addr will be 0 since this is the page address, so we 93 * can use them for flags. 94 */ 95 #define XSK_NEXT_PG_CONTIG_SHIFT 0 96 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 97 98 /* AF_XDP core. */ 99 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, 100 struct xdp_umem *umem); 101 int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev, 102 u16 queue_id, u16 flags); 103 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs, 104 struct net_device *dev, u16 queue_id); 105 int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs); 106 void xp_destroy(struct xsk_buff_pool *pool); 107 void xp_get_pool(struct xsk_buff_pool *pool); 108 bool xp_put_pool(struct xsk_buff_pool *pool); 109 void xp_clear_dev(struct xsk_buff_pool *pool); 110 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 111 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs); 112 113 /* AF_XDP, and XDP core. */ 114 void xp_free(struct xdp_buff_xsk *xskb); 115 116 static inline void xp_init_xskb_addr(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, 117 u64 addr) 118 { 119 xskb->orig_addr = addr; 120 xskb->xdp.data_hard_start = pool->addrs + addr + pool->headroom; 121 } 122 123 static inline void xp_init_xskb_dma(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool, 124 dma_addr_t *dma_pages, u64 addr) 125 { 126 xskb->frame_dma = (dma_pages[addr >> PAGE_SHIFT] & ~XSK_NEXT_PG_CONTIG_MASK) + 127 (addr & ~PAGE_MASK); 128 xskb->dma = xskb->frame_dma + pool->headroom + XDP_PACKET_HEADROOM; 129 } 130 131 /* AF_XDP ZC drivers, via xdp_sock_buff.h */ 132 void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq); 133 int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, 134 unsigned long attrs, struct page **pages, u32 nr_pages); 135 void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs); 136 struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool); 137 u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max); 138 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count); 139 void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr); 140 dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr); 141 static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb) 142 { 143 return xskb->dma; 144 } 145 146 static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb) 147 { 148 return xskb->frame_dma; 149 } 150 151 void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb); 152 static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb) 153 { 154 xp_dma_sync_for_cpu_slow(xskb); 155 } 156 157 void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma, 158 size_t size); 159 static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool, 160 dma_addr_t dma, size_t size) 161 { 162 if (!pool->dma_need_sync) 163 return; 164 165 xp_dma_sync_for_device_slow(pool, dma, size); 166 } 167 168 /* Masks for xdp_umem_page flags. 169 * The low 12-bits of the addr will be 0 since this is the page address, so we 170 * can use them for flags. 171 */ 172 #define XSK_NEXT_PG_CONTIG_SHIFT 0 173 #define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT) 174 175 static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool, 176 u64 addr, u32 len) 177 { 178 bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE; 179 180 if (likely(!cross_pg)) 181 return false; 182 183 if (pool->dma_pages_cnt) { 184 return !(pool->dma_pages[addr >> PAGE_SHIFT] & 185 XSK_NEXT_PG_CONTIG_MASK); 186 } 187 188 /* skb path */ 189 return addr + len > pool->addrs_cnt; 190 } 191 192 static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr) 193 { 194 return addr & pool->chunk_mask; 195 } 196 197 static inline u64 xp_unaligned_extract_addr(u64 addr) 198 { 199 return addr & XSK_UNALIGNED_BUF_ADDR_MASK; 200 } 201 202 static inline u64 xp_unaligned_extract_offset(u64 addr) 203 { 204 return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT; 205 } 206 207 static inline u64 xp_unaligned_add_offset_to_addr(u64 addr) 208 { 209 return xp_unaligned_extract_addr(addr) + 210 xp_unaligned_extract_offset(addr); 211 } 212 213 static inline u32 xp_aligned_extract_idx(struct xsk_buff_pool *pool, u64 addr) 214 { 215 return xp_aligned_extract_addr(pool, addr) >> pool->chunk_shift; 216 } 217 218 static inline void xp_release(struct xdp_buff_xsk *xskb) 219 { 220 if (xskb->pool->unaligned) 221 xskb->pool->free_heads[xskb->pool->free_heads_cnt++] = xskb; 222 } 223 224 static inline u64 xp_get_handle(struct xdp_buff_xsk *xskb) 225 { 226 u64 offset = xskb->xdp.data - xskb->xdp.data_hard_start; 227 228 offset += xskb->pool->headroom; 229 if (!xskb->pool->unaligned) 230 return xskb->orig_addr + offset; 231 return xskb->orig_addr + (offset << XSK_UNALIGNED_BUF_OFFSET_SHIFT); 232 } 233 234 #endif /* XSK_BUFF_POOL_H_ */ 235