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 BIT(3) 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 /* Statistics */ 75 u64 rx_dropped; 76 u64 rx_queue_full; 77 78 /* When __xsk_generic_xmit() must return before it sees the EOP descriptor for the current 79 * packet, the partially built skb is saved here so that packet building can resume in next 80 * call of __xsk_generic_xmit(). 81 */ 82 struct sk_buff *skb; 83 bool drain_cont; 84 85 struct list_head map_list; 86 /* Protects map_list */ 87 spinlock_t map_list_lock; 88 u32 max_tx_budget; 89 /* Protects multiple processes in the control path */ 90 struct mutex mutex; 91 struct xsk_queue *fq_tmp; /* Only as tmp storage before bind */ 92 struct xsk_queue *cq_tmp; /* Only as tmp storage before bind */ 93 }; 94 95 /* 96 * AF_XDP TX metadata hooks for network devices. 97 * The following hooks can be defined; unless noted otherwise, they are 98 * optional and can be filled with a null pointer. 99 * 100 * void (*tmo_request_timestamp)(void *priv) 101 * Called when AF_XDP frame requested egress timestamp. 102 * 103 * u64 (*tmo_fill_timestamp)(void *priv) 104 * Called when AF_XDP frame, that had requested egress timestamp, 105 * received a completion. The hook needs to return the actual HW timestamp. 106 * 107 * void (*tmo_request_checksum)(u16 csum_start, u16 csum_offset, void *priv) 108 * Called when AF_XDP frame requested HW checksum offload. csum_start 109 * indicates position where checksumming should start. 110 * csum_offset indicates position where checksum should be stored. 111 * 112 * void (*tmo_request_launch_time)(u64 launch_time, void *priv) 113 * Called when AF_XDP frame requested launch time HW offload support. 114 * launch_time indicates the PTP time at which the device can schedule the 115 * packet for transmission. 116 */ 117 struct xsk_tx_metadata_ops { 118 void (*tmo_request_timestamp)(void *priv); 119 u64 (*tmo_fill_timestamp)(void *priv); 120 void (*tmo_request_checksum)(u16 csum_start, u16 csum_offset, void *priv); 121 void (*tmo_request_launch_time)(u64 launch_time, void *priv); 122 }; 123 124 #ifdef CONFIG_XDP_SOCKETS 125 126 int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp); 127 int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp); 128 void __xsk_map_flush(struct list_head *flush_list); 129 INDIRECT_CALLABLE_DECLARE(void xsk_destruct_skb(struct sk_buff *)); 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 compl->tx_timestamp = NULL; 145 146 if (!meta) 147 return; 148 149 /* we can only arrive here if the completion timestamp has been 150 * requested via XDP_TXMD_FLAGS_TIMESTAMP, see xsk_tx_metadata_request 151 */ 152 153 compl->tx_timestamp = &meta->completion.tx_timestamp; 154 } 155 156 /** 157 * xsk_tx_metadata_complete - Evaluate AF_XDP TX metadata at completion 158 * and call appropriate xsk_tx_metadata_ops operation. 159 * @compl: pointer to completion metadata produced from xsk_tx_metadata_to_compl 160 * @ops: pointer to struct xsk_tx_metadata_ops 161 * @priv: pointer to driver-private aread 162 * 163 * This function should be called by the networking device upon 164 * AF_XDP egress completion. 165 */ 166 static inline void xsk_tx_metadata_complete(struct xsk_tx_metadata_compl *compl, 167 const struct xsk_tx_metadata_ops *ops, 168 void *priv) 169 { 170 if (!compl) 171 return; 172 if (!compl->tx_timestamp) 173 return; 174 175 *compl->tx_timestamp = ops->tmo_fill_timestamp(priv); 176 } 177 178 #else 179 180 static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) 181 { 182 return -ENOTSUPP; 183 } 184 185 static inline int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp) 186 { 187 return -EOPNOTSUPP; 188 } 189 190 static inline void __xsk_map_flush(struct list_head *flush_list) 191 { 192 } 193 194 #ifdef CONFIG_MITIGATION_RETPOLINE 195 static inline void xsk_destruct_skb(struct sk_buff *skb) 196 { 197 } 198 #endif 199 200 static inline void xsk_tx_metadata_to_compl(struct xsk_tx_metadata *meta, 201 struct xsk_tx_metadata_compl *compl) 202 { 203 } 204 205 static inline void xsk_tx_metadata_complete(struct xsk_tx_metadata_compl *compl, 206 const struct xsk_tx_metadata_ops *ops, 207 void *priv) 208 { 209 } 210 211 #endif /* CONFIG_XDP_SOCKETS */ 212 #endif /* _LINUX_XDP_SOCK_H */ 213