xsk_buff_pool.c

  1// SPDX-License-Identifier: GPL-2.0
  2
  3#include <linux/netdevice.h>
  4#include <net/netdev_lock.h>
  5#include <net/xsk_buff_pool.h>
  6#include <net/xdp_sock.h>
  7#include <net/xdp_sock_drv.h>
  8
  9#include "xsk_queue.h"
 10#include "xdp_umem.h"
 11#include "xsk.h"
 12
 13#define ETH_PAD_LEN (ETH_HLEN + 2 * VLAN_HLEN  + ETH_FCS_LEN)
 14
 15void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
 16{
 17	if (!xs->tx)
 18		return;
 19
 20	spin_lock(&pool->xsk_tx_list_lock);
 21	list_add_rcu(&xs->tx_list, &pool->xsk_tx_list);
 22	spin_unlock(&pool->xsk_tx_list_lock);
 23}
 24
 25void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
 26{
 27	if (!xs->tx)
 28		return;
 29
 30	spin_lock(&pool->xsk_tx_list_lock);
 31	list_del_rcu(&xs->tx_list);
 32	spin_unlock(&pool->xsk_tx_list_lock);
 33}
 34
 35void xp_destroy(struct xsk_buff_pool *pool)
 36{
 37	if (!pool)
 38		return;
 39
 40	kvfree(pool->tx_descs);
 41	kvfree(pool->heads);
 42	kvfree(pool);
 43}
 44
 45int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs)
 46{
 47	pool->tx_descs = kvcalloc(xs->tx->nentries, sizeof(*pool->tx_descs),
 48				  GFP_KERNEL);
 49	if (!pool->tx_descs)
 50		return -ENOMEM;
 51
 52	return 0;
 53}
 54
 55struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
 56						struct xdp_umem *umem)
 57{
 58	bool unaligned = umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG;
 59	struct xsk_buff_pool *pool;
 60	struct xdp_buff_xsk *xskb;
 61	u32 i, entries;
 62
 63	entries = unaligned ? umem->chunks : 0;
 64	pool = kvzalloc(struct_size(pool, free_heads, entries),	GFP_KERNEL);
 65	if (!pool)
 66		goto out;
 67
 68	pool->heads = kvcalloc(umem->chunks, sizeof(*pool->heads), GFP_KERNEL);
 69	if (!pool->heads)
 70		goto out;
 71
 72	if (xs->tx)
 73		if (xp_alloc_tx_descs(pool, xs))
 74			goto out;
 75
 76	pool->chunk_mask = ~((u64)umem->chunk_size - 1);
 77	pool->addrs_cnt = umem->size;
 78	pool->heads_cnt = umem->chunks;
 79	pool->free_heads_cnt = umem->chunks;
 80	pool->headroom = umem->headroom;
 81	pool->chunk_size = umem->chunk_size;
 82	pool->chunk_shift = ffs(umem->chunk_size) - 1;
 83	pool->unaligned = unaligned;
 84	pool->frame_len = umem->chunk_size - umem->headroom -
 85		XDP_PACKET_HEADROOM;
 86	pool->umem = umem;
 87	pool->addrs = umem->addrs;
 88	pool->tx_metadata_len = umem->tx_metadata_len;
 89	pool->tx_sw_csum = umem->flags & XDP_UMEM_TX_SW_CSUM;
 90	spin_lock_init(&pool->rx_lock);
 91	INIT_LIST_HEAD(&pool->free_list);
 92	INIT_LIST_HEAD(&pool->xskb_list);
 93	INIT_LIST_HEAD(&pool->xsk_tx_list);
 94	spin_lock_init(&pool->xsk_tx_list_lock);
 95	spin_lock_init(&pool->cq_prod_lock);
 96	spin_lock_init(&pool->cq_cached_prod_lock);
 97	refcount_set(&pool->users, 1);
 98
 99	pool->fq = xs->fq_tmp;
100	pool->cq = xs->cq_tmp;
101
102	for (i = 0; i < pool->free_heads_cnt; i++) {
103		xskb = &pool->heads[i];
104		xskb->pool = pool;
105		xskb->xdp.frame_sz = umem->chunk_size - umem->headroom;
106		INIT_LIST_HEAD(&xskb->list_node);
107		if (pool->unaligned)
108			pool->free_heads[i] = xskb;
109		else
110			xp_init_xskb_addr(xskb, pool, (u64)i * pool->chunk_size);
111	}
112
113	return pool;
114
115out:
116	xp_destroy(pool);
117	return NULL;
118}
119
120void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq)
121{
122	u32 i;
123
124	for (i = 0; i < pool->heads_cnt; i++)
125		pool->heads[i].xdp.rxq = rxq;
126}
127EXPORT_SYMBOL(xp_set_rxq_info);
128
129void xp_fill_cb(struct xsk_buff_pool *pool, struct xsk_cb_desc *desc)
130{
131	u32 i;
132
133	for (i = 0; i < pool->heads_cnt; i++) {
134		struct xdp_buff_xsk *xskb = &pool->heads[i];
135
136		memcpy(xskb->cb + desc->off, desc->src, desc->bytes);
137	}
138}
139EXPORT_SYMBOL(xp_fill_cb);
140
141static void xp_disable_drv_zc(struct xsk_buff_pool *pool)
142{
143	struct netdev_bpf bpf;
144	int err;
145
146	ASSERT_RTNL();
147
148	if (pool->umem->zc) {
149		bpf.command = XDP_SETUP_XSK_POOL;
150		bpf.xsk.pool = NULL;
151		bpf.xsk.queue_id = pool->queue_id;
152
153		err = pool->netdev->netdev_ops->ndo_bpf(pool->netdev, &bpf);
154
155		if (err)
156			WARN(1, "Failed to disable zero-copy!\n");
157	}
158}
159
160int xp_assign_dev(struct xsk_buff_pool *pool,
161		  struct net_device *netdev, u16 queue_id, u16 flags)
162{
163	u32 needed = netdev->mtu + ETH_PAD_LEN;
164	u32 segs = netdev->xdp_zc_max_segs;
165	bool mbuf = flags & XDP_USE_SG;
166	bool force_zc, force_copy;
167	struct netdev_bpf bpf;
168	u32 frame_size;
169	int err = 0;
170
171	ASSERT_RTNL();
172
173	force_zc = flags & XDP_ZEROCOPY;
174	force_copy = flags & XDP_COPY;
175
176	if (force_zc && force_copy)
177		return -EINVAL;
178
179	if (xsk_get_pool_from_qid(netdev, queue_id))
180		return -EBUSY;
181
182	pool->netdev = netdev;
183	pool->queue_id = queue_id;
184	err = xsk_reg_pool_at_qid(netdev, pool, queue_id);
185	if (err)
186		return err;
187
188	if (mbuf)
189		pool->umem->flags |= XDP_UMEM_SG_FLAG;
190
191	if (flags & XDP_USE_NEED_WAKEUP)
192		pool->uses_need_wakeup = true;
193	/* Tx needs to be explicitly woken up the first time.  Also
194	 * for supporting drivers that do not implement this
195	 * feature. They will always have to call sendto() or poll().
196	 */
197	pool->cached_need_wakeup = XDP_WAKEUP_TX;
198
199	dev_hold(netdev);
200
201	if (force_copy)
202		/* For copy-mode, we are done. */
203		return 0;
204
205	if ((netdev->xdp_features & NETDEV_XDP_ACT_XSK) != NETDEV_XDP_ACT_XSK) {
206		err = -EOPNOTSUPP;
207		goto err_unreg_pool;
208	}
209
210	if (mbuf) {
211		if (segs == 1) {
212			err = -EOPNOTSUPP;
213			goto err_unreg_pool;
214		}
215	} else {
216		segs = 1;
217	}
218
219	/* open-code xsk_pool_get_rx_frame_size() as pool->dev is not
220	 * set yet at this point; we are before getting down to driver
221	 */
222	frame_size = __xsk_pool_get_rx_frame_size(pool) -
223		     xsk_pool_get_tailroom(mbuf);
224	frame_size = ALIGN_DOWN(frame_size, 128);
225
226	if (needed > frame_size * segs) {
227		err = -EINVAL;
228		goto err_unreg_pool;
229	}
230
231	if (dev_get_min_mp_channel_count(netdev)) {
232		err = -EBUSY;
233		goto err_unreg_pool;
234	}
235
236	bpf.command = XDP_SETUP_XSK_POOL;
237	bpf.xsk.pool = pool;
238	bpf.xsk.queue_id = queue_id;
239
240	netdev_ops_assert_locked(netdev);
241	err = netdev->netdev_ops->ndo_bpf(netdev, &bpf);
242	if (err)
243		goto err_unreg_pool;
244
245	if (!pool->dma_pages) {
246		WARN(1, "Driver did not DMA map zero-copy buffers");
247		err = -EINVAL;
248		goto err_unreg_xsk;
249	}
250	pool->umem->zc = true;
251	pool->xdp_zc_max_segs = netdev->xdp_zc_max_segs;
252	return 0;
253
254err_unreg_xsk:
255	xp_disable_drv_zc(pool);
256err_unreg_pool:
257	if (!force_zc)
258		err = 0; /* fallback to copy mode */
259	if (err) {
260		xsk_clear_pool_at_qid(netdev, queue_id);
261		dev_put(netdev);
262	}
263	return err;
264}
265
266int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs,
267			 struct net_device *dev, u16 queue_id)
268{
269	u16 flags;
270	struct xdp_umem *umem = umem_xs->umem;
271
272	/* One fill and completion ring required for each queue id. */
273	if (!pool->fq || !pool->cq)
274		return -EINVAL;
275
276	flags = umem->zc ? XDP_ZEROCOPY : XDP_COPY;
277
278	if (umem->flags & XDP_UMEM_SG_FLAG)
279		flags |= XDP_USE_SG;
280
281	if (umem_xs->pool->uses_need_wakeup)
282		flags |= XDP_USE_NEED_WAKEUP;
283
284	return xp_assign_dev(pool, dev, queue_id, flags);
285}
286
287void xp_clear_dev(struct xsk_buff_pool *pool)
288{
289	struct net_device *netdev = pool->netdev;
290
291	if (!pool->netdev)
292		return;
293
294	netdev_lock_ops(netdev);
295	xp_disable_drv_zc(pool);
296	xsk_clear_pool_at_qid(pool->netdev, pool->queue_id);
297	pool->netdev = NULL;
298	netdev_unlock_ops(netdev);
299	dev_put(netdev);
300}
301
302static void xp_release_deferred(struct work_struct *work)
303{
304	struct xsk_buff_pool *pool = container_of(work, struct xsk_buff_pool,
305						  work);
306
307	rtnl_lock();
308	xp_clear_dev(pool);
309	rtnl_unlock();
310
311	if (pool->fq) {
312		xskq_destroy(pool->fq);
313		pool->fq = NULL;
314	}
315
316	if (pool->cq) {
317		xskq_destroy(pool->cq);
318		pool->cq = NULL;
319	}
320
321	xdp_put_umem(pool->umem, false);
322	xp_destroy(pool);
323}
324
325void xp_get_pool(struct xsk_buff_pool *pool)
326{
327	refcount_inc(&pool->users);
328}
329
330bool xp_put_pool(struct xsk_buff_pool *pool)
331{
332	if (!pool)
333		return false;
334
335	if (refcount_dec_and_test(&pool->users)) {
336		INIT_WORK(&pool->work, xp_release_deferred);
337		schedule_work(&pool->work);
338		return true;
339	}
340
341	return false;
342}
343
344static struct xsk_dma_map *xp_find_dma_map(struct xsk_buff_pool *pool)
345{
346	struct xsk_dma_map *dma_map;
347
348	list_for_each_entry(dma_map, &pool->umem->xsk_dma_list, list) {
349		if (dma_map->netdev == pool->netdev)
350			return dma_map;
351	}
352
353	return NULL;
354}
355
356static struct xsk_dma_map *xp_create_dma_map(struct device *dev, struct net_device *netdev,
357					     u32 nr_pages, struct xdp_umem *umem)
358{
359	struct xsk_dma_map *dma_map;
360
361	dma_map = kzalloc(sizeof(*dma_map), GFP_KERNEL);
362	if (!dma_map)
363		return NULL;
364
365	dma_map->dma_pages = kvcalloc(nr_pages, sizeof(*dma_map->dma_pages), GFP_KERNEL);
366	if (!dma_map->dma_pages) {
367		kfree(dma_map);
368		return NULL;
369	}
370
371	dma_map->netdev = netdev;
372	dma_map->dev = dev;
373	dma_map->dma_pages_cnt = nr_pages;
374	refcount_set(&dma_map->users, 1);
375	list_add(&dma_map->list, &umem->xsk_dma_list);
376	return dma_map;
377}
378
379static void xp_destroy_dma_map(struct xsk_dma_map *dma_map)
380{
381	list_del(&dma_map->list);
382	kvfree(dma_map->dma_pages);
383	kfree(dma_map);
384}
385
386static void __xp_dma_unmap(struct xsk_dma_map *dma_map, unsigned long attrs)
387{
388	dma_addr_t *dma;
389	u32 i;
390
391	for (i = 0; i < dma_map->dma_pages_cnt; i++) {
392		dma = &dma_map->dma_pages[i];
393		if (*dma) {
394			*dma &= ~XSK_NEXT_PG_CONTIG_MASK;
395			dma_unmap_page_attrs(dma_map->dev, *dma, PAGE_SIZE,
396					     DMA_BIDIRECTIONAL, attrs);
397			*dma = 0;
398		}
399	}
400
401	xp_destroy_dma_map(dma_map);
402}
403
404void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs)
405{
406	struct xsk_dma_map *dma_map;
407
408	if (!pool->dma_pages)
409		return;
410
411	dma_map = xp_find_dma_map(pool);
412	if (!dma_map) {
413		WARN(1, "Could not find dma_map for device");
414		return;
415	}
416
417	if (refcount_dec_and_test(&dma_map->users))
418		__xp_dma_unmap(dma_map, attrs);
419
420	kvfree(pool->dma_pages);
421	pool->dma_pages = NULL;
422	pool->dma_pages_cnt = 0;
423	pool->dev = NULL;
424}
425EXPORT_SYMBOL(xp_dma_unmap);
426
427static void xp_check_dma_contiguity(struct xsk_dma_map *dma_map)
428{
429	u32 i;
430
431	for (i = 0; i < dma_map->dma_pages_cnt - 1; i++) {
432		if (dma_map->dma_pages[i] + PAGE_SIZE == dma_map->dma_pages[i + 1])
433			dma_map->dma_pages[i] |= XSK_NEXT_PG_CONTIG_MASK;
434		else
435			dma_map->dma_pages[i] &= ~XSK_NEXT_PG_CONTIG_MASK;
436	}
437}
438
439static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_map)
440{
441	if (!pool->unaligned) {
442		u32 i;
443
444		for (i = 0; i < pool->heads_cnt; i++) {
445			struct xdp_buff_xsk *xskb = &pool->heads[i];
446			u64 orig_addr;
447
448			orig_addr = xskb->xdp.data_hard_start - pool->addrs - pool->headroom;
449			xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, orig_addr);
450		}
451	}
452
453	pool->dma_pages = kvcalloc(dma_map->dma_pages_cnt, sizeof(*pool->dma_pages), GFP_KERNEL);
454	if (!pool->dma_pages)
455		return -ENOMEM;
456
457	pool->dev = dma_map->dev;
458	pool->dma_pages_cnt = dma_map->dma_pages_cnt;
459	memcpy(pool->dma_pages, dma_map->dma_pages,
460	       pool->dma_pages_cnt * sizeof(*pool->dma_pages));
461
462	return 0;
463}
464
465int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
466	       unsigned long attrs, struct page **pages, u32 nr_pages)
467{
468	struct xsk_dma_map *dma_map;
469	dma_addr_t dma;
470	int err;
471	u32 i;
472
473	dma_map = xp_find_dma_map(pool);
474	if (dma_map) {
475		err = xp_init_dma_info(pool, dma_map);
476		if (err)
477			return err;
478
479		refcount_inc(&dma_map->users);
480		return 0;
481	}
482
483	dma_map = xp_create_dma_map(dev, pool->netdev, nr_pages, pool->umem);
484	if (!dma_map)
485		return -ENOMEM;
486
487	for (i = 0; i < dma_map->dma_pages_cnt; i++) {
488		dma = dma_map_page_attrs(dev, pages[i], 0, PAGE_SIZE,
489					 DMA_BIDIRECTIONAL, attrs);
490		if (dma_mapping_error(dev, dma)) {
491			__xp_dma_unmap(dma_map, attrs);
492			return -ENOMEM;
493		}
494		dma_map->dma_pages[i] = dma;
495	}
496
497	if (pool->unaligned)
498		xp_check_dma_contiguity(dma_map);
499
500	err = xp_init_dma_info(pool, dma_map);
501	if (err) {
502		__xp_dma_unmap(dma_map, attrs);
503		return err;
504	}
505
506	return 0;
507}
508EXPORT_SYMBOL(xp_dma_map);
509
510static bool xp_addr_crosses_non_contig_pg(struct xsk_buff_pool *pool,
511					  u64 addr)
512{
513	return xp_desc_crosses_non_contig_pg(pool, addr, pool->chunk_size);
514}
515
516static bool xp_check_unaligned(struct xsk_buff_pool *pool, u64 *addr)
517{
518	*addr = xp_unaligned_extract_addr(*addr);
519	if (*addr >= pool->addrs_cnt ||
520	    *addr + pool->chunk_size > pool->addrs_cnt ||
521	    xp_addr_crosses_non_contig_pg(pool, *addr))
522		return false;
523	return true;
524}
525
526static bool xp_check_aligned(struct xsk_buff_pool *pool, u64 *addr)
527{
528	*addr = xp_aligned_extract_addr(pool, *addr);
529	return *addr < pool->addrs_cnt;
530}
531
532static struct xdp_buff_xsk *xp_get_xskb(struct xsk_buff_pool *pool, u64 addr)
533{
534	struct xdp_buff_xsk *xskb;
535
536	if (pool->unaligned) {
537		xskb = pool->free_heads[--pool->free_heads_cnt];
538		xp_init_xskb_addr(xskb, pool, addr);
539		if (pool->dma_pages)
540			xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr);
541	} else {
542		xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)];
543	}
544
545	return xskb;
546}
547
548static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool)
549{
550	struct xdp_buff_xsk *xskb;
551	u64 addr;
552	bool ok;
553
554	if (pool->free_heads_cnt == 0)
555		return NULL;
556
557	for (;;) {
558		if (!xskq_cons_peek_addr_unchecked(pool->fq, &addr)) {
559			pool->fq->queue_empty_descs++;
560			return NULL;
561		}
562
563		ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
564		     xp_check_aligned(pool, &addr);
565		if (!ok) {
566			pool->fq->invalid_descs++;
567			xskq_cons_release(pool->fq);
568			continue;
569		}
570		break;
571	}
572
573	xskb = xp_get_xskb(pool, addr);
574
575	xskq_cons_release(pool->fq);
576	return xskb;
577}
578
579struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool)
580{
581	struct xdp_buff_xsk *xskb;
582
583	if (!pool->free_list_cnt) {
584		xskb = __xp_alloc(pool);
585		if (!xskb)
586			return NULL;
587	} else {
588		pool->free_list_cnt--;
589		xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk,
590					list_node);
591		list_del_init(&xskb->list_node);
592	}
593
594	xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM;
595	xskb->xdp.data_meta = xskb->xdp.data;
596	xskb->xdp.flags = 0;
597
598	if (pool->dev)
599		xp_dma_sync_for_device(pool, xskb->dma, pool->frame_len);
600
601	return &xskb->xdp;
602}
603EXPORT_SYMBOL(xp_alloc);
604
605static u32 xp_alloc_new_from_fq(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
606{
607	u32 i, cached_cons, nb_entries;
608
609	if (max > pool->free_heads_cnt)
610		max = pool->free_heads_cnt;
611	max = xskq_cons_nb_entries(pool->fq, max);
612
613	cached_cons = pool->fq->cached_cons;
614	nb_entries = max;
615	i = max;
616	while (i--) {
617		struct xdp_buff_xsk *xskb;
618		u64 addr;
619		bool ok;
620
621		__xskq_cons_read_addr_unchecked(pool->fq, cached_cons++, &addr);
622
623		ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
624			xp_check_aligned(pool, &addr);
625		if (unlikely(!ok)) {
626			pool->fq->invalid_descs++;
627			nb_entries--;
628			continue;
629		}
630
631		xskb = xp_get_xskb(pool, addr);
632
633		*xdp = &xskb->xdp;
634		xdp++;
635	}
636
637	xskq_cons_release_n(pool->fq, max);
638	return nb_entries;
639}
640
641static u32 xp_alloc_reused(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 nb_entries)
642{
643	struct xdp_buff_xsk *xskb;
644	u32 i;
645
646	nb_entries = min_t(u32, nb_entries, pool->free_list_cnt);
647
648	i = nb_entries;
649	while (i--) {
650		xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk, list_node);
651		list_del_init(&xskb->list_node);
652
653		*xdp = &xskb->xdp;
654		xdp++;
655	}
656	pool->free_list_cnt -= nb_entries;
657
658	return nb_entries;
659}
660
661static u32 xp_alloc_slow(struct xsk_buff_pool *pool, struct xdp_buff **xdp,
662			 u32 max)
663{
664	int i;
665
666	for (i = 0; i < max; i++) {
667		struct xdp_buff *buff;
668
669		buff = xp_alloc(pool);
670		if (unlikely(!buff))
671			return i;
672		*xdp = buff;
673		xdp++;
674	}
675
676	return max;
677}
678
679u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
680{
681	u32 nb_entries1 = 0, nb_entries2;
682
683	if (unlikely(pool->dev && dma_dev_need_sync(pool->dev)))
684		return xp_alloc_slow(pool, xdp, max);
685
686	if (unlikely(pool->free_list_cnt)) {
687		nb_entries1 = xp_alloc_reused(pool, xdp, max);
688		if (nb_entries1 == max)
689			return nb_entries1;
690
691		max -= nb_entries1;
692		xdp += nb_entries1;
693	}
694
695	nb_entries2 = xp_alloc_new_from_fq(pool, xdp, max);
696	if (!nb_entries2)
697		pool->fq->queue_empty_descs++;
698
699	return nb_entries1 + nb_entries2;
700}
701EXPORT_SYMBOL(xp_alloc_batch);
702
703bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count)
704{
705	u32 req_count, avail_count;
706
707	if (pool->free_list_cnt >= count)
708		return true;
709
710	req_count = count - pool->free_list_cnt;
711	avail_count = xskq_cons_nb_entries(pool->fq, req_count);
712	if (!avail_count)
713		pool->fq->queue_empty_descs++;
714
715	return avail_count >= req_count;
716}
717EXPORT_SYMBOL(xp_can_alloc);
718
719void xp_free(struct xdp_buff_xsk *xskb)
720{
721	if (!list_empty(&xskb->list_node))
722		return;
723
724	xskb->pool->free_list_cnt++;
725	list_add(&xskb->list_node, &xskb->pool->free_list);
726}
727EXPORT_SYMBOL(xp_free);
728
729static u64 __xp_raw_get_addr(const struct xsk_buff_pool *pool, u64 addr)
730{
731	return pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
732}
733
734static void *__xp_raw_get_data(const struct xsk_buff_pool *pool, u64 addr)
735{
736	return pool->addrs + addr;
737}
738
739void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
740{
741	return __xp_raw_get_data(pool, __xp_raw_get_addr(pool, addr));
742}
743EXPORT_SYMBOL(xp_raw_get_data);
744
745static dma_addr_t __xp_raw_get_dma(const struct xsk_buff_pool *pool, u64 addr)
746{
747	return (pool->dma_pages[addr >> PAGE_SHIFT] &
748		~XSK_NEXT_PG_CONTIG_MASK) +
749		(addr & ~PAGE_MASK);
750}
751
752dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
753{
754	return __xp_raw_get_dma(pool, __xp_raw_get_addr(pool, addr));
755}
756EXPORT_SYMBOL(xp_raw_get_dma);
757
758/**
759 * xp_raw_get_ctx - get &xdp_desc context
760 * @pool: XSk buff pool desc address belongs to
761 * @addr: desc address (from userspace)
762 *
763 * Helper for getting desc's DMA address and metadata pointer, if present.
764 * Saves one call on hotpath, double calculation of the actual address,
765 * and inline checks for metadata presence and sanity.
766 *
767 * Return: new &xdp_desc_ctx struct containing desc's DMA address and metadata
768 * pointer, if it is present and valid (initialized to %NULL otherwise).
769 */
770struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr)
771{
772	struct xdp_desc_ctx ret;
773
774	addr = __xp_raw_get_addr(pool, addr);
775
776	ret.dma = __xp_raw_get_dma(pool, addr);
777	ret.meta = __xsk_buff_get_metadata(pool, __xp_raw_get_data(pool, addr));
778
779	return ret;
780}
781EXPORT_SYMBOL(xp_raw_get_ctx);