1
2
3#include <net/xsk_buff_pool.h>
4#include <net/xdp_sock.h>
5#include <net/xdp_sock_drv.h>
6
7#include "xsk_queue.h"
8#include "xdp_umem.h"
9#include "xsk.h"
10
11void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
12{
13 unsigned long flags;
14
15 if (!xs->tx)
16 return;
17
18 spin_lock_irqsave(&pool->xsk_tx_list_lock, flags);
19 list_add_rcu(&xs->tx_list, &pool->xsk_tx_list);
20 spin_unlock_irqrestore(&pool->xsk_tx_list_lock, flags);
21}
22
23void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
24{
25 unsigned long flags;
26
27 if (!xs->tx)
28 return;
29
30 spin_lock_irqsave(&pool->xsk_tx_list_lock, flags);
31 list_del_rcu(&xs->tx_list);
32 spin_unlock_irqrestore(&pool->xsk_tx_list_lock, flags);
33}
34
35void xp_destroy(struct xsk_buff_pool *pool)
36{
37 if (!pool)
38 return;
39
40 kvfree(pool->heads);
41 kvfree(pool);
42}
43
44struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
45 struct xdp_umem *umem)
46{
47 struct xsk_buff_pool *pool;
48 struct xdp_buff_xsk *xskb;
49 u32 i;
50
51 pool = kvzalloc(struct_size(pool, free_heads, umem->chunks),
52 GFP_KERNEL);
53 if (!pool)
54 goto out;
55
56 pool->heads = kvcalloc(umem->chunks, sizeof(*pool->heads), GFP_KERNEL);
57 if (!pool->heads)
58 goto out;
59
60 pool->chunk_mask = ~((u64)umem->chunk_size - 1);
61 pool->addrs_cnt = umem->size;
62 pool->heads_cnt = umem->chunks;
63 pool->free_heads_cnt = umem->chunks;
64 pool->headroom = umem->headroom;
65 pool->chunk_size = umem->chunk_size;
66 pool->unaligned = umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG;
67 pool->frame_len = umem->chunk_size - umem->headroom -
68 XDP_PACKET_HEADROOM;
69 pool->umem = umem;
70 pool->addrs = umem->addrs;
71 INIT_LIST_HEAD(&pool->free_list);
72 INIT_LIST_HEAD(&pool->xsk_tx_list);
73 spin_lock_init(&pool->xsk_tx_list_lock);
74 spin_lock_init(&pool->cq_lock);
75 refcount_set(&pool->users, 1);
76
77 pool->fq = xs->fq_tmp;
78 pool->cq = xs->cq_tmp;
79
80 for (i = 0; i < pool->free_heads_cnt; i++) {
81 xskb = &pool->heads[i];
82 xskb->pool = pool;
83 xskb->xdp.frame_sz = umem->chunk_size - umem->headroom;
84 pool->free_heads[i] = xskb;
85 }
86
87 return pool;
88
89out:
90 xp_destroy(pool);
91 return NULL;
92}
93
94void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq)
95{
96 u32 i;
97
98 for (i = 0; i < pool->heads_cnt; i++)
99 pool->heads[i].xdp.rxq = rxq;
100}
101EXPORT_SYMBOL(xp_set_rxq_info);
102
103static void xp_disable_drv_zc(struct xsk_buff_pool *pool)
104{
105 struct netdev_bpf bpf;
106 int err;
107
108 ASSERT_RTNL();
109
110 if (pool->umem->zc) {
111 bpf.command = XDP_SETUP_XSK_POOL;
112 bpf.xsk.pool = NULL;
113 bpf.xsk.queue_id = pool->queue_id;
114
115 err = pool->netdev->netdev_ops->ndo_bpf(pool->netdev, &bpf);
116
117 if (err)
118 WARN(1, "Failed to disable zero-copy!\n");
119 }
120}
121
122static int __xp_assign_dev(struct xsk_buff_pool *pool,
123 struct net_device *netdev, u16 queue_id, u16 flags)
124{
125 bool force_zc, force_copy;
126 struct netdev_bpf bpf;
127 int err = 0;
128
129 ASSERT_RTNL();
130
131 force_zc = flags & XDP_ZEROCOPY;
132 force_copy = flags & XDP_COPY;
133
134 if (force_zc && force_copy)
135 return -EINVAL;
136
137 if (xsk_get_pool_from_qid(netdev, queue_id))
138 return -EBUSY;
139
140 pool->netdev = netdev;
141 pool->queue_id = queue_id;
142 err = xsk_reg_pool_at_qid(netdev, pool, queue_id);
143 if (err)
144 return err;
145
146 if (flags & XDP_USE_NEED_WAKEUP)
147 pool->uses_need_wakeup = true;
148
149
150
151
152 pool->cached_need_wakeup = XDP_WAKEUP_TX;
153
154 dev_hold(netdev);
155
156 if (force_copy)
157
158 return 0;
159
160 if (!netdev->netdev_ops->ndo_bpf ||
161 !netdev->netdev_ops->ndo_xsk_wakeup) {
162 err = -EOPNOTSUPP;
163 goto err_unreg_pool;
164 }
165
166 bpf.command = XDP_SETUP_XSK_POOL;
167 bpf.xsk.pool = pool;
168 bpf.xsk.queue_id = queue_id;
169
170 err = netdev->netdev_ops->ndo_bpf(netdev, &bpf);
171 if (err)
172 goto err_unreg_pool;
173
174 if (!pool->dma_pages) {
175 WARN(1, "Driver did not DMA map zero-copy buffers");
176 err = -EINVAL;
177 goto err_unreg_xsk;
178 }
179 pool->umem->zc = true;
180 return 0;
181
182err_unreg_xsk:
183 xp_disable_drv_zc(pool);
184err_unreg_pool:
185 if (!force_zc)
186 err = 0;
187 if (err) {
188 xsk_clear_pool_at_qid(netdev, queue_id);
189 dev_put(netdev);
190 }
191 return err;
192}
193
194int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev,
195 u16 queue_id, u16 flags)
196{
197 return __xp_assign_dev(pool, dev, queue_id, flags);
198}
199
200int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_umem *umem,
201 struct net_device *dev, u16 queue_id)
202{
203 u16 flags;
204
205
206 if (!pool->fq || !pool->cq)
207 return -EINVAL;
208
209 flags = umem->zc ? XDP_ZEROCOPY : XDP_COPY;
210 if (pool->uses_need_wakeup)
211 flags |= XDP_USE_NEED_WAKEUP;
212
213 return __xp_assign_dev(pool, dev, queue_id, flags);
214}
215
216void xp_clear_dev(struct xsk_buff_pool *pool)
217{
218 if (!pool->netdev)
219 return;
220
221 xp_disable_drv_zc(pool);
222 xsk_clear_pool_at_qid(pool->netdev, pool->queue_id);
223 dev_put(pool->netdev);
224 pool->netdev = NULL;
225}
226
227static void xp_release_deferred(struct work_struct *work)
228{
229 struct xsk_buff_pool *pool = container_of(work, struct xsk_buff_pool,
230 work);
231
232 rtnl_lock();
233 xp_clear_dev(pool);
234 rtnl_unlock();
235
236 if (pool->fq) {
237 xskq_destroy(pool->fq);
238 pool->fq = NULL;
239 }
240
241 if (pool->cq) {
242 xskq_destroy(pool->cq);
243 pool->cq = NULL;
244 }
245
246 xdp_put_umem(pool->umem, false);
247 xp_destroy(pool);
248}
249
250void xp_get_pool(struct xsk_buff_pool *pool)
251{
252 refcount_inc(&pool->users);
253}
254
255bool xp_put_pool(struct xsk_buff_pool *pool)
256{
257 if (!pool)
258 return false;
259
260 if (refcount_dec_and_test(&pool->users)) {
261 INIT_WORK(&pool->work, xp_release_deferred);
262 schedule_work(&pool->work);
263 return true;
264 }
265
266 return false;
267}
268
269static struct xsk_dma_map *xp_find_dma_map(struct xsk_buff_pool *pool)
270{
271 struct xsk_dma_map *dma_map;
272
273 list_for_each_entry(dma_map, &pool->umem->xsk_dma_list, list) {
274 if (dma_map->netdev == pool->netdev)
275 return dma_map;
276 }
277
278 return NULL;
279}
280
281static struct xsk_dma_map *xp_create_dma_map(struct device *dev, struct net_device *netdev,
282 u32 nr_pages, struct xdp_umem *umem)
283{
284 struct xsk_dma_map *dma_map;
285
286 dma_map = kzalloc(sizeof(*dma_map), GFP_KERNEL);
287 if (!dma_map)
288 return NULL;
289
290 dma_map->dma_pages = kvcalloc(nr_pages, sizeof(*dma_map->dma_pages), GFP_KERNEL);
291 if (!dma_map->dma_pages) {
292 kfree(dma_map);
293 return NULL;
294 }
295
296 dma_map->netdev = netdev;
297 dma_map->dev = dev;
298 dma_map->dma_need_sync = false;
299 dma_map->dma_pages_cnt = nr_pages;
300 refcount_set(&dma_map->users, 1);
301 list_add(&dma_map->list, &umem->xsk_dma_list);
302 return dma_map;
303}
304
305static void xp_destroy_dma_map(struct xsk_dma_map *dma_map)
306{
307 list_del(&dma_map->list);
308 kvfree(dma_map->dma_pages);
309 kfree(dma_map);
310}
311
312static void __xp_dma_unmap(struct xsk_dma_map *dma_map, unsigned long attrs)
313{
314 dma_addr_t *dma;
315 u32 i;
316
317 for (i = 0; i < dma_map->dma_pages_cnt; i++) {
318 dma = &dma_map->dma_pages[i];
319 if (*dma) {
320 dma_unmap_page_attrs(dma_map->dev, *dma, PAGE_SIZE,
321 DMA_BIDIRECTIONAL, attrs);
322 *dma = 0;
323 }
324 }
325
326 xp_destroy_dma_map(dma_map);
327}
328
329void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs)
330{
331 struct xsk_dma_map *dma_map;
332
333 if (pool->dma_pages_cnt == 0)
334 return;
335
336 dma_map = xp_find_dma_map(pool);
337 if (!dma_map) {
338 WARN(1, "Could not find dma_map for device");
339 return;
340 }
341
342 if (!refcount_dec_and_test(&dma_map->users))
343 return;
344
345 __xp_dma_unmap(dma_map, attrs);
346 kvfree(pool->dma_pages);
347 pool->dma_pages_cnt = 0;
348 pool->dev = NULL;
349}
350EXPORT_SYMBOL(xp_dma_unmap);
351
352static void xp_check_dma_contiguity(struct xsk_dma_map *dma_map)
353{
354 u32 i;
355
356 for (i = 0; i < dma_map->dma_pages_cnt - 1; i++) {
357 if (dma_map->dma_pages[i] + PAGE_SIZE == dma_map->dma_pages[i + 1])
358 dma_map->dma_pages[i] |= XSK_NEXT_PG_CONTIG_MASK;
359 else
360 dma_map->dma_pages[i] &= ~XSK_NEXT_PG_CONTIG_MASK;
361 }
362}
363
364static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_map)
365{
366 pool->dma_pages = kvcalloc(dma_map->dma_pages_cnt, sizeof(*pool->dma_pages), GFP_KERNEL);
367 if (!pool->dma_pages)
368 return -ENOMEM;
369
370 pool->dev = dma_map->dev;
371 pool->dma_pages_cnt = dma_map->dma_pages_cnt;
372 pool->dma_need_sync = dma_map->dma_need_sync;
373 memcpy(pool->dma_pages, dma_map->dma_pages,
374 pool->dma_pages_cnt * sizeof(*pool->dma_pages));
375
376 return 0;
377}
378
379int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
380 unsigned long attrs, struct page **pages, u32 nr_pages)
381{
382 struct xsk_dma_map *dma_map;
383 dma_addr_t dma;
384 int err;
385 u32 i;
386
387 dma_map = xp_find_dma_map(pool);
388 if (dma_map) {
389 err = xp_init_dma_info(pool, dma_map);
390 if (err)
391 return err;
392
393 refcount_inc(&dma_map->users);
394 return 0;
395 }
396
397 dma_map = xp_create_dma_map(dev, pool->netdev, nr_pages, pool->umem);
398 if (!dma_map)
399 return -ENOMEM;
400
401 for (i = 0; i < dma_map->dma_pages_cnt; i++) {
402 dma = dma_map_page_attrs(dev, pages[i], 0, PAGE_SIZE,
403 DMA_BIDIRECTIONAL, attrs);
404 if (dma_mapping_error(dev, dma)) {
405 __xp_dma_unmap(dma_map, attrs);
406 return -ENOMEM;
407 }
408 if (dma_need_sync(dev, dma))
409 dma_map->dma_need_sync = true;
410 dma_map->dma_pages[i] = dma;
411 }
412
413 if (pool->unaligned)
414 xp_check_dma_contiguity(dma_map);
415
416 err = xp_init_dma_info(pool, dma_map);
417 if (err) {
418 __xp_dma_unmap(dma_map, attrs);
419 return err;
420 }
421
422 return 0;
423}
424EXPORT_SYMBOL(xp_dma_map);
425
426static bool xp_addr_crosses_non_contig_pg(struct xsk_buff_pool *pool,
427 u64 addr)
428{
429 return xp_desc_crosses_non_contig_pg(pool, addr, pool->chunk_size);
430}
431
432static bool xp_check_unaligned(struct xsk_buff_pool *pool, u64 *addr)
433{
434 *addr = xp_unaligned_extract_addr(*addr);
435 if (*addr >= pool->addrs_cnt ||
436 *addr + pool->chunk_size > pool->addrs_cnt ||
437 xp_addr_crosses_non_contig_pg(pool, *addr))
438 return false;
439 return true;
440}
441
442static bool xp_check_aligned(struct xsk_buff_pool *pool, u64 *addr)
443{
444 *addr = xp_aligned_extract_addr(pool, *addr);
445 return *addr < pool->addrs_cnt;
446}
447
448static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool)
449{
450 struct xdp_buff_xsk *xskb;
451 u64 addr;
452 bool ok;
453
454 if (pool->free_heads_cnt == 0)
455 return NULL;
456
457 xskb = pool->free_heads[--pool->free_heads_cnt];
458
459 for (;;) {
460 if (!xskq_cons_peek_addr_unchecked(pool->fq, &addr)) {
461 pool->fq->queue_empty_descs++;
462 xp_release(xskb);
463 return NULL;
464 }
465
466 ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
467 xp_check_aligned(pool, &addr);
468 if (!ok) {
469 pool->fq->invalid_descs++;
470 xskq_cons_release(pool->fq);
471 continue;
472 }
473 break;
474 }
475 xskq_cons_release(pool->fq);
476
477 xskb->orig_addr = addr;
478 xskb->xdp.data_hard_start = pool->addrs + addr + pool->headroom;
479 if (pool->dma_pages_cnt) {
480 xskb->frame_dma = (pool->dma_pages[addr >> PAGE_SHIFT] &
481 ~XSK_NEXT_PG_CONTIG_MASK) +
482 (addr & ~PAGE_MASK);
483 xskb->dma = xskb->frame_dma + pool->headroom +
484 XDP_PACKET_HEADROOM;
485 }
486 return xskb;
487}
488
489struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool)
490{
491 struct xdp_buff_xsk *xskb;
492
493 if (!pool->free_list_cnt) {
494 xskb = __xp_alloc(pool);
495 if (!xskb)
496 return NULL;
497 } else {
498 pool->free_list_cnt--;
499 xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk,
500 free_list_node);
501 list_del(&xskb->free_list_node);
502 }
503
504 xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM;
505 xskb->xdp.data_meta = xskb->xdp.data;
506
507 if (pool->dma_need_sync) {
508 dma_sync_single_range_for_device(pool->dev, xskb->dma, 0,
509 pool->frame_len,
510 DMA_BIDIRECTIONAL);
511 }
512 return &xskb->xdp;
513}
514EXPORT_SYMBOL(xp_alloc);
515
516bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count)
517{
518 if (pool->free_list_cnt >= count)
519 return true;
520 return xskq_cons_has_entries(pool->fq, count - pool->free_list_cnt);
521}
522EXPORT_SYMBOL(xp_can_alloc);
523
524void xp_free(struct xdp_buff_xsk *xskb)
525{
526 xskb->pool->free_list_cnt++;
527 list_add(&xskb->free_list_node, &xskb->pool->free_list);
528}
529EXPORT_SYMBOL(xp_free);
530
531void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
532{
533 addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
534 return pool->addrs + addr;
535}
536EXPORT_SYMBOL(xp_raw_get_data);
537
538dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
539{
540 addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
541 return (pool->dma_pages[addr >> PAGE_SHIFT] &
542 ~XSK_NEXT_PG_CONTIG_MASK) +
543 (addr & ~PAGE_MASK);
544}
545EXPORT_SYMBOL(xp_raw_get_dma);
546
547void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb)
548{
549 dma_sync_single_range_for_cpu(xskb->pool->dev, xskb->dma, 0,
550 xskb->pool->frame_len, DMA_BIDIRECTIONAL);
551}
552EXPORT_SYMBOL(xp_dma_sync_for_cpu_slow);
553
554void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma,
555 size_t size)
556{
557 dma_sync_single_range_for_device(pool->dev, dma, 0,
558 size, DMA_BIDIRECTIONAL);
559}
560EXPORT_SYMBOL(xp_dma_sync_for_device_slow);
561