1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (C) 2025 Intel Corporation */ 3 4 #define DEFAULT_SYMBOL_NAMESPACE "LIBETH_XDP" 5 6 #include <linux/export.h> 7 8 #include <net/libeth/xdp.h> 9 10 #include "priv.h" 11 12 /* XDPSQ sharing */ 13 14 DEFINE_STATIC_KEY_FALSE(libeth_xdpsq_share); 15 EXPORT_SYMBOL_GPL(libeth_xdpsq_share); 16 17 void __libeth_xdpsq_get(struct libeth_xdpsq_lock *lock, 18 const struct net_device *dev) 19 { 20 bool warn; 21 22 spin_lock_init(&lock->lock); 23 lock->share = true; 24 25 warn = !static_key_enabled(&libeth_xdpsq_share); 26 static_branch_inc(&libeth_xdpsq_share); 27 28 if (warn && net_ratelimit()) 29 netdev_warn(dev, "XDPSQ sharing enabled, possible XDP Tx slowdown\n"); 30 } 31 EXPORT_SYMBOL_GPL(__libeth_xdpsq_get); 32 33 void __libeth_xdpsq_put(struct libeth_xdpsq_lock *lock, 34 const struct net_device *dev) 35 { 36 static_branch_dec(&libeth_xdpsq_share); 37 38 if (!static_key_enabled(&libeth_xdpsq_share) && net_ratelimit()) 39 netdev_notice(dev, "XDPSQ sharing disabled\n"); 40 41 lock->share = false; 42 } 43 EXPORT_SYMBOL_GPL(__libeth_xdpsq_put); 44 45 void __acquires(&lock->lock) 46 __libeth_xdpsq_lock(struct libeth_xdpsq_lock *lock) 47 { 48 spin_lock(&lock->lock); 49 } 50 EXPORT_SYMBOL_GPL(__libeth_xdpsq_lock); 51 52 void __releases(&lock->lock) 53 __libeth_xdpsq_unlock(struct libeth_xdpsq_lock *lock) 54 { 55 spin_unlock(&lock->lock); 56 } 57 EXPORT_SYMBOL_GPL(__libeth_xdpsq_unlock); 58 59 /* XDPSQ clean-up timers */ 60 61 /** 62 * libeth_xdpsq_init_timer - initialize an XDPSQ clean-up timer 63 * @timer: timer to initialize 64 * @xdpsq: queue this timer belongs to 65 * @lock: corresponding XDPSQ lock 66 * @poll: queue polling/completion function 67 * 68 * XDPSQ clean-up timers must be set up before using at the queue configuration 69 * time. Set the required pointers and the cleaning callback. 70 */ 71 void libeth_xdpsq_init_timer(struct libeth_xdpsq_timer *timer, void *xdpsq, 72 struct libeth_xdpsq_lock *lock, 73 void (*poll)(struct work_struct *work)) 74 { 75 timer->xdpsq = xdpsq; 76 timer->lock = lock; 77 78 INIT_DELAYED_WORK(&timer->dwork, poll); 79 } 80 EXPORT_SYMBOL_GPL(libeth_xdpsq_init_timer); 81 82 /* ``XDP_TX`` bulking */ 83 84 static void __cold 85 libeth_xdp_tx_return_one(const struct libeth_xdp_tx_frame *frm) 86 { 87 if (frm->len_fl & LIBETH_XDP_TX_MULTI) 88 libeth_xdp_return_frags(frm->data + frm->soff, true); 89 90 libeth_xdp_return_va(frm->data, true); 91 } 92 93 static void __cold 94 libeth_xdp_tx_return_bulk(const struct libeth_xdp_tx_frame *bq, u32 count) 95 { 96 for (u32 i = 0; i < count; i++) { 97 const struct libeth_xdp_tx_frame *frm = &bq[i]; 98 99 if (!(frm->len_fl & LIBETH_XDP_TX_FIRST)) 100 continue; 101 102 libeth_xdp_tx_return_one(frm); 103 } 104 } 105 106 static void __cold libeth_trace_xdp_exception(const struct net_device *dev, 107 const struct bpf_prog *prog, 108 u32 act) 109 { 110 trace_xdp_exception(dev, prog, act); 111 } 112 113 /** 114 * libeth_xdp_tx_exception - handle Tx exceptions of XDP frames 115 * @bq: XDP Tx frame bulk 116 * @sent: number of frames sent successfully (from this bulk) 117 * @flags: internal libeth_xdp flags (.ndo_xdp_xmit etc.) 118 * 119 * Cold helper used by __libeth_xdp_tx_flush_bulk(), do not call directly. 120 * Reports XDP Tx exceptions, frees the frames that won't be sent or adjust 121 * the Tx bulk to try again later. 122 */ 123 void __cold libeth_xdp_tx_exception(struct libeth_xdp_tx_bulk *bq, u32 sent, 124 u32 flags) 125 { 126 const struct libeth_xdp_tx_frame *pos = &bq->bulk[sent]; 127 u32 left = bq->count - sent; 128 129 if (!(flags & LIBETH_XDP_TX_NDO)) 130 libeth_trace_xdp_exception(bq->dev, bq->prog, XDP_TX); 131 132 if (!(flags & LIBETH_XDP_TX_DROP)) { 133 memmove(bq->bulk, pos, left * sizeof(*bq->bulk)); 134 bq->count = left; 135 136 return; 137 } 138 139 if (!(flags & LIBETH_XDP_TX_NDO)) 140 libeth_xdp_tx_return_bulk(pos, left); 141 else 142 libeth_xdp_xmit_return_bulk(pos, left, bq->dev); 143 144 bq->count = 0; 145 } 146 EXPORT_SYMBOL_GPL(libeth_xdp_tx_exception); 147 148 /* .ndo_xdp_xmit() implementation */ 149 150 u32 __cold libeth_xdp_xmit_return_bulk(const struct libeth_xdp_tx_frame *bq, 151 u32 count, const struct net_device *dev) 152 { 153 u32 n = 0; 154 155 for (u32 i = 0; i < count; i++) { 156 const struct libeth_xdp_tx_frame *frm = &bq[i]; 157 dma_addr_t dma; 158 159 if (frm->flags & LIBETH_XDP_TX_FIRST) 160 dma = *libeth_xdp_xmit_frame_dma(frm->xdpf); 161 else 162 dma = dma_unmap_addr(frm, dma); 163 164 dma_unmap_page(dev->dev.parent, dma, dma_unmap_len(frm, len), 165 DMA_TO_DEVICE); 166 167 /* Actual xdp_frames are freed by the core */ 168 n += !!(frm->flags & LIBETH_XDP_TX_FIRST); 169 } 170 171 return n; 172 } 173 EXPORT_SYMBOL_GPL(libeth_xdp_xmit_return_bulk); 174 175 /* Rx polling path */ 176 177 /** 178 * libeth_xdp_return_buff_slow - free &libeth_xdp_buff 179 * @xdp: buffer to free/return 180 * 181 * Slowpath version of libeth_xdp_return_buff() to be called on exceptions, 182 * queue clean-ups etc., without unwanted inlining. 183 */ 184 void __cold libeth_xdp_return_buff_slow(struct libeth_xdp_buff *xdp) 185 { 186 __libeth_xdp_return_buff(xdp, false); 187 } 188 EXPORT_SYMBOL_GPL(libeth_xdp_return_buff_slow); 189 190 /* Tx buffer completion */ 191 192 static void libeth_xdp_put_netmem_bulk(netmem_ref netmem, 193 struct xdp_frame_bulk *bq) 194 { 195 if (unlikely(bq->count == XDP_BULK_QUEUE_SIZE)) 196 xdp_flush_frame_bulk(bq); 197 198 bq->q[bq->count++] = netmem; 199 } 200 201 /** 202 * libeth_xdp_return_buff_bulk - free &xdp_buff as part of a bulk 203 * @sinfo: shared info corresponding to the buffer 204 * @bq: XDP frame bulk to store the buffer 205 * @frags: whether the buffer has frags 206 * 207 * Same as xdp_return_frame_bulk(), but for &libeth_xdp_buff, speeds up Tx 208 * completion of ``XDP_TX`` buffers and allows to free them in same bulks 209 * with &xdp_frame buffers. 210 */ 211 void libeth_xdp_return_buff_bulk(const struct skb_shared_info *sinfo, 212 struct xdp_frame_bulk *bq, bool frags) 213 { 214 if (!frags) 215 goto head; 216 217 for (u32 i = 0; i < sinfo->nr_frags; i++) 218 libeth_xdp_put_netmem_bulk(skb_frag_netmem(&sinfo->frags[i]), 219 bq); 220 221 head: 222 libeth_xdp_put_netmem_bulk(virt_to_netmem(sinfo), bq); 223 } 224 EXPORT_SYMBOL_GPL(libeth_xdp_return_buff_bulk); 225 226 /* Module */ 227 228 static const struct libeth_xdp_ops xdp_ops __initconst = { 229 .bulk = libeth_xdp_return_buff_bulk, 230 }; 231 232 static int __init libeth_xdp_module_init(void) 233 { 234 libeth_attach_xdp(&xdp_ops); 235 236 return 0; 237 } 238 module_init(libeth_xdp_module_init); 239 240 static void __exit libeth_xdp_module_exit(void) 241 { 242 libeth_detach_xdp(); 243 } 244 module_exit(libeth_xdp_module_exit); 245 246 MODULE_DESCRIPTION("Common Ethernet library - XDP infra"); 247 MODULE_IMPORT_NS("LIBETH"); 248 MODULE_LICENSE("GPL"); 249