1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* AF_XDP internal functions 3 * Copyright(c) 2018 Intel Corporation. 4 */ 5 6 #ifndef _LINUX_XDP_SOCK_H 7 #define _LINUX_XDP_SOCK_H 8 9 #include <linux/bpf.h> 10 #include <linux/workqueue.h> 11 #include <linux/if_xdp.h> 12 #include <linux/mutex.h> 13 #include <linux/spinlock.h> 14 #include <linux/mm.h> 15 #include <net/sock.h> 16 17 #define XDP_UMEM_SG_FLAG (1 << 1) 18 19 struct net_device; 20 struct xsk_queue; 21 struct xdp_buff; 22 23 struct xdp_umem { 24 void *addrs; 25 u64 size; 26 u32 headroom; 27 u32 chunk_size; 28 u32 chunks; 29 u32 npgs; 30 struct user_struct *user; 31 refcount_t users; 32 u8 flags; 33 u8 tx_metadata_len; 34 bool zc; 35 struct page **pgs; 36 int id; 37 struct list_head xsk_dma_list; 38 struct work_struct work; 39 }; 40 41 struct xsk_map { 42 struct bpf_map map; 43 spinlock_t lock; /* Synchronize map updates */ 44 atomic_t count; 45 struct xdp_sock __rcu *xsk_map[]; 46 }; 47 48 struct xdp_sock { 49 /* struct sock must be the first member of struct xdp_sock */ 50 struct sock sk; 51 struct xsk_queue *rx ____cacheline_aligned_in_smp; 52 struct net_device *dev; 53 struct xdp_umem *umem; 54 struct list_head flush_node; 55 struct xsk_buff_pool *pool; 56 u16 queue_id; 57 bool zc; 58 bool sg; 59 enum { 60 XSK_READY = 0, 61 XSK_BOUND, 62 XSK_UNBOUND, 63 } state; 64 65 struct xsk_queue *tx ____cacheline_aligned_in_smp; 66 struct list_head tx_list; 67 /* record the number of tx descriptors sent by this xsk and 68 * when it exceeds MAX_PER_SOCKET_BUDGET, an opportunity needs 69 * to be given to other xsks for sending tx descriptors, thereby 70 * preventing other XSKs from being starved. 71 */ 72 u32 tx_budget_spent; 73 74 /* Protects generic receive. */ 75 spinlock_t rx_lock; 76 77 /* Statistics */ 78 u64 rx_dropped; 79 u64 rx_queue_full; 80 81 /* When __xsk_generic_xmit() must return before it sees the EOP descriptor for the current 82 * packet, the partially built skb is saved here so that packet building can resume in next 83 * call of __xsk_generic_xmit(). 84 */ 85 struct sk_buff *skb; 86 87 struct list_head map_list; 88 /* Protects map_list */ 89 spinlock_t map_list_lock; 90 /* Protects multiple processes in the control path */ 91 struct mutex mutex; 92 struct xsk_queue *fq_tmp; /* Only as tmp storage before bind */ 93 struct xsk_queue *cq_tmp; /* Only as tmp storage before bind */ 94 }; 95 96 /* 97 * AF_XDP TX metadata hooks for network devices. 98 * The following hooks can be defined; unless noted otherwise, they are 99 * optional and can be filled with a null pointer. 100 * 101 * void (*tmo_request_timestamp)(void *priv) 102 * Called when AF_XDP frame requested egress timestamp. 103 * 104 * u64 (*tmo_fill_timestamp)(void *priv) 105 * Called when AF_XDP frame, that had requested egress timestamp, 106 * received a completion. The hook needs to return the actual HW timestamp. 107 * 108 * void (*tmo_request_checksum)(u16 csum_start, u16 csum_offset, void *priv) 109 * Called when AF_XDP frame requested HW checksum offload. csum_start 110 * indicates position where checksumming should start. 111 * csum_offset indicates position where checksum should be stored. 112 * 113 * void (*tmo_request_launch_time)(u64 launch_time, void *priv) 114 * Called when AF_XDP frame requested launch time HW offload support. 115 * launch_time indicates the PTP time at which the device can schedule the 116 * packet for transmission. 117 */ 118 struct xsk_tx_metadata_ops { 119 void (*tmo_request_timestamp)(void *priv); 120 u64 (*tmo_fill_timestamp)(void *priv); 121 void (*tmo_request_checksum)(u16 csum_start, u16 csum_offset, void *priv); 122 void (*tmo_request_launch_time)(u64 launch_time, void *priv); 123 }; 124 125 #ifdef CONFIG_XDP_SOCKETS 126 127 int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp); 128 int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp); 129 void __xsk_map_flush(struct list_head *flush_list); 130 131 /** 132 * xsk_tx_metadata_to_compl - Save enough relevant metadata information 133 * to perform tx completion in the future. 134 * @meta: pointer to AF_XDP metadata area 135 * @compl: pointer to output struct xsk_tx_metadata_to_compl 136 * 137 * This function should be called by the networking device when 138 * it prepares AF_XDP egress packet. The value of @compl should be stored 139 * and passed to xsk_tx_metadata_complete upon TX completion. 140 */ 141 static inline void xsk_tx_metadata_to_compl(struct xsk_tx_metadata *meta, 142 struct xsk_tx_metadata_compl *compl) 143 { 144 if (!meta) 145 return; 146 147 if (meta->flags & XDP_TXMD_FLAGS_TIMESTAMP) 148 compl->tx_timestamp = &meta->completion.tx_timestamp; 149 else 150 compl->tx_timestamp = NULL; 151 } 152 153 /** 154 * xsk_tx_metadata_request - Evaluate AF_XDP TX metadata at submission 155 * and call appropriate xsk_tx_metadata_ops operation. 156 * @meta: pointer to AF_XDP metadata area 157 * @ops: pointer to struct xsk_tx_metadata_ops 158 * @priv: pointer to driver-private aread 159 * 160 * This function should be called by the networking device when 161 * it prepares AF_XDP egress packet. 162 */ 163 static inline void xsk_tx_metadata_request(const struct xsk_tx_metadata *meta, 164 const struct xsk_tx_metadata_ops *ops, 165 void *priv) 166 { 167 if (!meta) 168 return; 169 170 if (ops->tmo_request_launch_time) 171 if (meta->flags & XDP_TXMD_FLAGS_LAUNCH_TIME) 172 ops->tmo_request_launch_time(meta->request.launch_time, 173 priv); 174 175 if (ops->tmo_request_timestamp) 176 if (meta->flags & XDP_TXMD_FLAGS_TIMESTAMP) 177 ops->tmo_request_timestamp(priv); 178 179 if (ops->tmo_request_checksum) 180 if (meta->flags & XDP_TXMD_FLAGS_CHECKSUM) 181 ops->tmo_request_checksum(meta->request.csum_start, 182 meta->request.csum_offset, priv); 183 } 184 185 /** 186 * xsk_tx_metadata_complete - Evaluate AF_XDP TX metadata at completion 187 * and call appropriate xsk_tx_metadata_ops operation. 188 * @compl: pointer to completion metadata produced from xsk_tx_metadata_to_compl 189 * @ops: pointer to struct xsk_tx_metadata_ops 190 * @priv: pointer to driver-private aread 191 * 192 * This function should be called by the networking device upon 193 * AF_XDP egress completion. 194 */ 195 static inline void xsk_tx_metadata_complete(struct xsk_tx_metadata_compl *compl, 196 const struct xsk_tx_metadata_ops *ops, 197 void *priv) 198 { 199 if (!compl) 200 return; 201 if (!compl->tx_timestamp) 202 return; 203 204 *compl->tx_timestamp = ops->tmo_fill_timestamp(priv); 205 } 206 207 #else 208 209 static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) 210 { 211 return -ENOTSUPP; 212 } 213 214 static inline int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp) 215 { 216 return -EOPNOTSUPP; 217 } 218 219 static inline void __xsk_map_flush(struct list_head *flush_list) 220 { 221 } 222 223 static inline void xsk_tx_metadata_to_compl(struct xsk_tx_metadata *meta, 224 struct xsk_tx_metadata_compl *compl) 225 { 226 } 227 228 static inline void xsk_tx_metadata_request(struct xsk_tx_metadata *meta, 229 const struct xsk_tx_metadata_ops *ops, 230 void *priv) 231 { 232 } 233 234 static inline void xsk_tx_metadata_complete(struct xsk_tx_metadata_compl *compl, 235 const struct xsk_tx_metadata_ops *ops, 236 void *priv) 237 { 238 } 239 240 #endif /* CONFIG_XDP_SOCKETS */ 241 #endif /* _LINUX_XDP_SOCK_H */ 242