[linux-block.git] / net / xdp / xsk_buff_pool.c

// SPDX-License-Identifier: GPL-2.0

#include <net/xsk_buff_pool.h>
#include <net/xdp_sock.h>
#include <net/xdp_sock_drv.h>

#include "xsk_queue.h"
#include "xdp_umem.h"
#include "xsk.h"

void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
{
	unsigned long flags;

	if (!xs->tx)
		return;

	spin_lock_irqsave(&pool->xsk_tx_list_lock, flags);
	list_add_rcu(&xs->tx_list, &pool->xsk_tx_list);
	spin_unlock_irqrestore(&pool->xsk_tx_list_lock, flags);
}

void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
{
	unsigned long flags;

	if (!xs->tx)
		return;

	spin_lock_irqsave(&pool->xsk_tx_list_lock, flags);
	list_del_rcu(&xs->tx_list);
	spin_unlock_irqrestore(&pool->xsk_tx_list_lock, flags);
}

void xp_destroy(struct xsk_buff_pool *pool)
{
	if (!pool)
		return;

	kvfree(pool->tx_descs);
	kvfree(pool->heads);
	kvfree(pool);
}

int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs)
{
	pool->tx_descs = kvcalloc(xs->tx->nentries, sizeof(*pool->tx_descs),
				  GFP_KERNEL);
	if (!pool->tx_descs)
		return -ENOMEM;

	return 0;
}

struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
						struct xdp_umem *umem)
{
	bool unaligned = umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG;
	struct xsk_buff_pool *pool;
	struct xdp_buff_xsk *xskb;
	u32 i, entries;

	entries = unaligned ? umem->chunks : 0;
	pool = kvzalloc(struct_size(pool, free_heads, entries),	GFP_KERNEL);
	if (!pool)
		goto out;

	pool->heads = kvcalloc(umem->chunks, sizeof(*pool->heads), GFP_KERNEL);
	if (!pool->heads)
		goto out;

	if (xs->tx)
		if (xp_alloc_tx_descs(pool, xs))
			goto out;

	pool->chunk_mask = ~((u64)umem->chunk_size - 1);
	pool->addrs_cnt = umem->size;
	pool->heads_cnt = umem->chunks;
	pool->free_heads_cnt = umem->chunks;
	pool->headroom = umem->headroom;
	pool->chunk_size = umem->chunk_size;
	pool->chunk_shift = ffs(umem->chunk_size) - 1;
	pool->unaligned = unaligned;
	pool->frame_len = umem->chunk_size - umem->headroom -
		XDP_PACKET_HEADROOM;
	pool->umem = umem;
	pool->addrs = umem->addrs;
	INIT_LIST_HEAD(&pool->free_list);
	INIT_LIST_HEAD(&pool->xskb_list);
	INIT_LIST_HEAD(&pool->xsk_tx_list);
	spin_lock_init(&pool->xsk_tx_list_lock);
	spin_lock_init(&pool->cq_lock);
	refcount_set(&pool->users, 1);

	pool->fq = xs->fq_tmp;
	pool->cq = xs->cq_tmp;

	for (i = 0; i < pool->free_heads_cnt; i++) {
		xskb = &pool->heads[i];
		xskb->pool = pool;
		xskb->xdp.frame_sz = umem->chunk_size - umem->headroom;
		INIT_LIST_HEAD(&xskb->free_list_node);
		INIT_LIST_HEAD(&xskb->xskb_list_node);
		if (pool->unaligned)
			pool->free_heads[i] = xskb;
		else
			xp_init_xskb_addr(xskb, pool, i * pool->chunk_size);
	}

	return pool;

out:
	xp_destroy(pool);
	return NULL;
}

void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq)
{
	u32 i;

	for (i = 0; i < pool->heads_cnt; i++)
		pool->heads[i].xdp.rxq = rxq;
}
EXPORT_SYMBOL(xp_set_rxq_info);

static void xp_disable_drv_zc(struct xsk_buff_pool *pool)
{
	struct netdev_bpf bpf;
	int err;

	ASSERT_RTNL();

	if (pool->umem->zc) {
		bpf.command = XDP_SETUP_XSK_POOL;
		bpf.xsk.pool = NULL;
		bpf.xsk.queue_id = pool->queue_id;

		err = pool->netdev->netdev_ops->ndo_bpf(pool->netdev, &bpf);

		if (err)
			WARN(1, "Failed to disable zero-copy!\n");
	}
}

#define NETDEV_XDP_ACT_ZC	(NETDEV_XDP_ACT_BASIC |		\
				 NETDEV_XDP_ACT_REDIRECT |	\
				 NETDEV_XDP_ACT_XSK_ZEROCOPY)

int xp_assign_dev(struct xsk_buff_pool *pool,
		  struct net_device *netdev, u16 queue_id, u16 flags)
{
	bool force_zc, force_copy;
	struct netdev_bpf bpf;
	int err = 0;

	ASSERT_RTNL();

	force_zc = flags & XDP_ZEROCOPY;
	force_copy = flags & XDP_COPY;

	if (force_zc && force_copy)
		return -EINVAL;

	if (xsk_get_pool_from_qid(netdev, queue_id))
		return -EBUSY;

	pool->netdev = netdev;
	pool->queue_id = queue_id;
	err = xsk_reg_pool_at_qid(netdev, pool, queue_id);
	if (err)
		return err;

	if (flags & XDP_USE_SG)
		pool->umem->flags |= XDP_UMEM_SG_FLAG;

	if (flags & XDP_USE_NEED_WAKEUP)
		pool->uses_need_wakeup = true;
	/* Tx needs to be explicitly woken up the first time.  Also
	 * for supporting drivers that do not implement this
	 * feature. They will always have to call sendto() or poll().
	 */
	pool->cached_need_wakeup = XDP_WAKEUP_TX;

	dev_hold(netdev);

	if (force_copy)
		/* For copy-mode, we are done. */
		return 0;

	if ((netdev->xdp_features & NETDEV_XDP_ACT_ZC) != NETDEV_XDP_ACT_ZC) {
		err = -EOPNOTSUPP;
		goto err_unreg_pool;
	}

	if (netdev->xdp_zc_max_segs == 1 && (flags & XDP_USE_SG)) {
		err = -EOPNOTSUPP;
		goto err_unreg_pool;
	}

	bpf.command = XDP_SETUP_XSK_POOL;
	bpf.xsk.pool = pool;
	bpf.xsk.queue_id = queue_id;

	err = netdev->netdev_ops->ndo_bpf(netdev, &bpf);
	if (err)
		goto err_unreg_pool;

	if (!pool->dma_pages) {
		WARN(1, "Driver did not DMA map zero-copy buffers");
		err = -EINVAL;
		goto err_unreg_xsk;
	}
	pool->umem->zc = true;
	return 0;

err_unreg_xsk:
	xp_disable_drv_zc(pool);
err_unreg_pool:
	if (!force_zc)
		err = 0; /* fallback to copy mode */
	if (err) {
		xsk_clear_pool_at_qid(netdev, queue_id);
		dev_put(netdev);
	}
	return err;
}

int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs,
			 struct net_device *dev, u16 queue_id)
{
	u16 flags;
	struct xdp_umem *umem = umem_xs->umem;

	/* One fill and completion ring required for each queue id. */
	if (!pool->fq || !pool->cq)
		return -EINVAL;

	flags = umem->zc ? XDP_ZEROCOPY : XDP_COPY;
	if (umem_xs->pool->uses_need_wakeup)
		flags |= XDP_USE_NEED_WAKEUP;

	return xp_assign_dev(pool, dev, queue_id, flags);
}

void xp_clear_dev(struct xsk_buff_pool *pool)
{
	if (!pool->netdev)
		return;

	xp_disable_drv_zc(pool);
	xsk_clear_pool_at_qid(pool->netdev, pool->queue_id);
	dev_put(pool->netdev);
	pool->netdev = NULL;
}

static void xp_release_deferred(struct work_struct *work)
{
	struct xsk_buff_pool *pool = container_of(work, struct xsk_buff_pool,
						  work);

	rtnl_lock();
	xp_clear_dev(pool);
	rtnl_unlock();

	if (pool->fq) {
		xskq_destroy(pool->fq);
		pool->fq = NULL;
	}

	if (pool->cq) {
		xskq_destroy(pool->cq);
		pool->cq = NULL;
	}

	xdp_put_umem(pool->umem, false);
	xp_destroy(pool);
}

void xp_get_pool(struct xsk_buff_pool *pool)
{
	refcount_inc(&pool->users);
}

bool xp_put_pool(struct xsk_buff_pool *pool)
{
	if (!pool)
		return false;

	if (refcount_dec_and_test(&pool->users)) {
		INIT_WORK(&pool->work, xp_release_deferred);
		schedule_work(&pool->work);
		return true;
	}

	return false;
}

static struct xsk_dma_map *xp_find_dma_map(struct xsk_buff_pool *pool)
{
	struct xsk_dma_map *dma_map;

	list_for_each_entry(dma_map, &pool->umem->xsk_dma_list, list) {
		if (dma_map->netdev == pool->netdev)
			return dma_map;
	}

	return NULL;
}

static struct xsk_dma_map *xp_create_dma_map(struct device *dev, struct net_device *netdev,
					     u32 nr_pages, struct xdp_umem *umem)
{
	struct xsk_dma_map *dma_map;

	dma_map = kzalloc(sizeof(*dma_map), GFP_KERNEL);
	if (!dma_map)
		return NULL;

	dma_map->dma_pages = kvcalloc(nr_pages, sizeof(*dma_map->dma_pages), GFP_KERNEL);
	if (!dma_map->dma_pages) {
		kfree(dma_map);
		return NULL;
	}

	dma_map->netdev = netdev;
	dma_map->dev = dev;
	dma_map->dma_need_sync = false;
	dma_map->dma_pages_cnt = nr_pages;
	refcount_set(&dma_map->users, 1);
	list_add(&dma_map->list, &umem->xsk_dma_list);
	return dma_map;
}

static void xp_destroy_dma_map(struct xsk_dma_map *dma_map)
{
	list_del(&dma_map->list);
	kvfree(dma_map->dma_pages);
	kfree(dma_map);
}

static void __xp_dma_unmap(struct xsk_dma_map *dma_map, unsigned long attrs)
{
	dma_addr_t *dma;
	u32 i;

	for (i = 0; i < dma_map->dma_pages_cnt; i++) {
		dma = &dma_map->dma_pages[i];
		if (*dma) {
			*dma &= ~XSK_NEXT_PG_CONTIG_MASK;
			dma_unmap_page_attrs(dma_map->dev, *dma, PAGE_SIZE,
					     DMA_BIDIRECTIONAL, attrs);
			*dma = 0;
		}
	}

	xp_destroy_dma_map(dma_map);
}

void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs)
{
	struct xsk_dma_map *dma_map;

	if (!pool->dma_pages)
		return;

	dma_map = xp_find_dma_map(pool);
	if (!dma_map) {
		WARN(1, "Could not find dma_map for device");
		return;
	}

	if (!refcount_dec_and_test(&dma_map->users))
		return;

	__xp_dma_unmap(dma_map, attrs);
	kvfree(pool->dma_pages);
	pool->dma_pages = NULL;
	pool->dma_pages_cnt = 0;
	pool->dev = NULL;
}
EXPORT_SYMBOL(xp_dma_unmap);

static void xp_check_dma_contiguity(struct xsk_dma_map *dma_map)
{
	u32 i;

	for (i = 0; i < dma_map->dma_pages_cnt - 1; i++) {
		if (dma_map->dma_pages[i] + PAGE_SIZE == dma_map->dma_pages[i + 1])
			dma_map->dma_pages[i] |= XSK_NEXT_PG_CONTIG_MASK;
		else
			dma_map->dma_pages[i] &= ~XSK_NEXT_PG_CONTIG_MASK;
	}
}

static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_map)
{
	if (!pool->unaligned) {
		u32 i;

		for (i = 0; i < pool->heads_cnt; i++) {
			struct xdp_buff_xsk *xskb = &pool->heads[i];

			xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, xskb->orig_addr);
		}
	}

	pool->dma_pages = kvcalloc(dma_map->dma_pages_cnt, sizeof(*pool->dma_pages), GFP_KERNEL);
	if (!pool->dma_pages)
		return -ENOMEM;

	pool->dev = dma_map->dev;
	pool->dma_pages_cnt = dma_map->dma_pages_cnt;
	pool->dma_need_sync = dma_map->dma_need_sync;
	memcpy(pool->dma_pages, dma_map->dma_pages,
	       pool->dma_pages_cnt * sizeof(*pool->dma_pages));

	return 0;
}

int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
	       unsigned long attrs, struct page **pages, u32 nr_pages)
{
	struct xsk_dma_map *dma_map;
	dma_addr_t dma;
	int err;
	u32 i;

	dma_map = xp_find_dma_map(pool);
	if (dma_map) {
		err = xp_init_dma_info(pool, dma_map);
		if (err)
			return err;

		refcount_inc(&dma_map->users);
		return 0;
	}

	dma_map = xp_create_dma_map(dev, pool->netdev, nr_pages, pool->umem);
	if (!dma_map)
		return -ENOMEM;

	for (i = 0; i < dma_map->dma_pages_cnt; i++) {
		dma = dma_map_page_attrs(dev, pages[i], 0, PAGE_SIZE,
					 DMA_BIDIRECTIONAL, attrs);
		if (dma_mapping_error(dev, dma)) {
			__xp_dma_unmap(dma_map, attrs);
			return -ENOMEM;
		}
		if (dma_need_sync(dev, dma))
			dma_map->dma_need_sync = true;
		dma_map->dma_pages[i] = dma;
	}

	if (pool->unaligned)
		xp_check_dma_contiguity(dma_map);

	err = xp_init_dma_info(pool, dma_map);
	if (err) {
		__xp_dma_unmap(dma_map, attrs);
		return err;
	}

	return 0;
}
EXPORT_SYMBOL(xp_dma_map);

static bool xp_addr_crosses_non_contig_pg(struct xsk_buff_pool *pool,
					  u64 addr)
{
	return xp_desc_crosses_non_contig_pg(pool, addr, pool->chunk_size);
}

static bool xp_check_unaligned(struct xsk_buff_pool *pool, u64 *addr)
{
	*addr = xp_unaligned_extract_addr(*addr);
	if (*addr >= pool->addrs_cnt ||
	    *addr + pool->chunk_size > pool->addrs_cnt ||
	    xp_addr_crosses_non_contig_pg(pool, *addr))
		return false;
	return true;
}

static bool xp_check_aligned(struct xsk_buff_pool *pool, u64 *addr)
{
	*addr = xp_aligned_extract_addr(pool, *addr);
	return *addr < pool->addrs_cnt;
}

static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool)
{
	struct xdp_buff_xsk *xskb;
	u64 addr;
	bool ok;

	if (pool->free_heads_cnt == 0)
		return NULL;

	for (;;) {
		if (!xskq_cons_peek_addr_unchecked(pool->fq, &addr)) {
			pool->fq->queue_empty_descs++;
			return NULL;
		}

		ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
		     xp_check_aligned(pool, &addr);
		if (!ok) {
			pool->fq->invalid_descs++;
			xskq_cons_release(pool->fq);
			continue;
		}
		break;
	}

	if (pool->unaligned) {
		xskb = pool->free_heads[--pool->free_heads_cnt];
		xp_init_xskb_addr(xskb, pool, addr);
		if (pool->dma_pages)
			xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr);
	} else {
		xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)];
	}

	xskq_cons_release(pool->fq);
	return xskb;
}

struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool)
{
	struct xdp_buff_xsk *xskb;

	if (!pool->free_list_cnt) {
		xskb = __xp_alloc(pool);
		if (!xskb)
			return NULL;
	} else {
		pool->free_list_cnt--;
		xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk,
					free_list_node);
		list_del_init(&xskb->free_list_node);
	}

	xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM;
	xskb->xdp.data_meta = xskb->xdp.data;

	if (pool->dma_need_sync) {
		dma_sync_single_range_for_device(pool->dev, xskb->dma, 0,
						 pool->frame_len,
						 DMA_BIDIRECTIONAL);
	}
	return &xskb->xdp;
}
EXPORT_SYMBOL(xp_alloc);

static u32 xp_alloc_new_from_fq(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
{
	u32 i, cached_cons, nb_entries;

	if (max > pool->free_heads_cnt)
		max = pool->free_heads_cnt;
	max = xskq_cons_nb_entries(pool->fq, max);

	cached_cons = pool->fq->cached_cons;
	nb_entries = max;
	i = max;
	while (i--) {
		struct xdp_buff_xsk *xskb;
		u64 addr;
		bool ok;

		__xskq_cons_read_addr_unchecked(pool->fq, cached_cons++, &addr);

		ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
			xp_check_aligned(pool, &addr);
		if (unlikely(!ok)) {
			pool->fq->invalid_descs++;
			nb_entries--;
			continue;
		}

		if (pool->unaligned) {
			xskb = pool->free_heads[--pool->free_heads_cnt];
			xp_init_xskb_addr(xskb, pool, addr);
			if (pool->dma_pages)
				xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr);
		} else {
			xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)];
		}

		*xdp = &xskb->xdp;
		xdp++;
	}

	xskq_cons_release_n(pool->fq, max);
	return nb_entries;
}

static u32 xp_alloc_reused(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 nb_entries)
{
	struct xdp_buff_xsk *xskb;
	u32 i;

	nb_entries = min_t(u32, nb_entries, pool->free_list_cnt);

	i = nb_entries;
	while (i--) {
		xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk, free_list_node);
		list_del_init(&xskb->free_list_node);

		*xdp = &xskb->xdp;
		xdp++;
	}
	pool->free_list_cnt -= nb_entries;

	return nb_entries;
}

u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
{
	u32 nb_entries1 = 0, nb_entries2;

	if (unlikely(pool->dma_need_sync)) {
		struct xdp_buff *buff;

		/* Slow path */
		buff = xp_alloc(pool);
		if (buff)
			*xdp = buff;
		return !!buff;
	}

	if (unlikely(pool->free_list_cnt)) {
		nb_entries1 = xp_alloc_reused(pool, xdp, max);
		if (nb_entries1 == max)
			return nb_entries1;

		max -= nb_entries1;
		xdp += nb_entries1;
	}

	nb_entries2 = xp_alloc_new_from_fq(pool, xdp, max);
	if (!nb_entries2)
		pool->fq->queue_empty_descs++;

	return nb_entries1 + nb_entries2;
}
EXPORT_SYMBOL(xp_alloc_batch);

bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count)
{
	if (pool->free_list_cnt >= count)
		return true;
	return xskq_cons_has_entries(pool->fq, count - pool->free_list_cnt);
}
EXPORT_SYMBOL(xp_can_alloc);

void xp_free(struct xdp_buff_xsk *xskb)
{
	if (!list_empty(&xskb->free_list_node))
		return;

	xskb->pool->free_list_cnt++;
	list_add(&xskb->free_list_node, &xskb->pool->free_list);
}
EXPORT_SYMBOL(xp_free);

void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
{
	addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
	return pool->addrs + addr;
}
EXPORT_SYMBOL(xp_raw_get_data);

dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
{
	addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
	return (pool->dma_pages[addr >> PAGE_SHIFT] &
		~XSK_NEXT_PG_CONTIG_MASK) +
		(addr & ~PAGE_MASK);
}
EXPORT_SYMBOL(xp_raw_get_dma);

void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb)
{
	dma_sync_single_range_for_cpu(xskb->pool->dev, xskb->dma, 0,
				      xskb->pool->frame_len, DMA_BIDIRECTIONAL);
}
EXPORT_SYMBOL(xp_dma_sync_for_cpu_slow);

void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma,
				 size_t size)
{
	dma_sync_single_range_for_device(pool->dev, dma, 0,
					 size, DMA_BIDIRECTIONAL);
}
EXPORT_SYMBOL(xp_dma_sync_for_device_slow);
Commit	Line	Data
2b43470a BT	1	// SPDX-License-Identifier: GPL-2.0
	2
	3	#include <net/xsk_buff_pool.h>
	4	#include <net/xdp_sock.h>
1c1efc2a	5	#include <net/xdp_sock_drv.h>
2b43470a BT	6
2b43470a BT	7	#include "xsk_queue.h"
1c1efc2a MK	8	#include "xdp_umem.h"
1c1efc2a MK	9	#include "xsk.h"
2b43470a	10
a5aa8e52 MK	11	void 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
	23	void 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
2b43470a BT	35	void xp_destroy(struct xsk_buff_pool *pool)
	36	{
	37	if (!pool)
	38	return;
	39
d1bc532e	40	kvfree(pool->tx_descs);
2b43470a BT	41	kvfree(pool->heads);
	42	kvfree(pool);
	43	}
	44
ba3beec2 MF	45	int 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
1c1efc2a MK	55	struct xsk_buff_pool xp_create_and_assign_umem(struct xdp_sock xs,
1c1efc2a MK	56	struct xdp_umem *umem)
2b43470a	57	{
94033cd8	58	bool unaligned = umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG;
2b43470a BT	59	struct xsk_buff_pool *pool;
2b43470a BT	60	struct xdp_buff_xsk *xskb;
94033cd8	61	u32 i, entries;
2b43470a	62
94033cd8 MK	63	entries = unaligned ? umem->chunks : 0;
94033cd8 MK	64	pool = kvzalloc(struct_size(pool, free_heads, entries), GFP_KERNEL);
2b43470a BT	65	if (!pool)
	66	goto out;
	67
1c1efc2a	68	pool->heads = kvcalloc(umem->chunks, sizeof(*pool->heads), GFP_KERNEL);
2b43470a BT	69	if (!pool->heads)
	70	goto out;
	71
ba3beec2 MF	72	if (xs->tx)
ba3beec2 MF	73	if (xp_alloc_tx_descs(pool, xs))
d1bc532e	74	goto out;
d1bc532e	75
1c1efc2a MK	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;
94033cd8 MK	82	pool->chunk_shift = ffs(umem->chunk_size) - 1;
94033cd8 MK	83	pool->unaligned = unaligned;
1c1efc2a MK	84	pool->frame_len = umem->chunk_size - umem->headroom -
1c1efc2a MK	85	XDP_PACKET_HEADROOM;
1742b3d5	86	pool->umem = umem;
7f7ffa4e	87	pool->addrs = umem->addrs;
2b43470a	88	INIT_LIST_HEAD(&pool->free_list);
24ea5012	89	INIT_LIST_HEAD(&pool->xskb_list);
a5aa8e52 MK	90	INIT_LIST_HEAD(&pool->xsk_tx_list);
a5aa8e52 MK	91	spin_lock_init(&pool->xsk_tx_list_lock);
f09ced40	92	spin_lock_init(&pool->cq_lock);
1c1efc2a	93	refcount_set(&pool->users, 1);
2b43470a	94
7361f9c3 MK	95	pool->fq = xs->fq_tmp;
7361f9c3 MK	96	pool->cq = xs->cq_tmp;
7361f9c3	97
2b43470a BT	98	for (i = 0; i < pool->free_heads_cnt; i++) {
	99	xskb = &pool->heads[i];
	100	xskb->pool = pool;
1c1efc2a	101	xskb->xdp.frame_sz = umem->chunk_size - umem->headroom;
5bec7ca2	102	INIT_LIST_HEAD(&xskb->free_list_node);
24ea5012	103	INIT_LIST_HEAD(&xskb->xskb_list_node);
94033cd8 MK	104	if (pool->unaligned)
	105	pool->free_heads[i] = xskb;
	106	else
	107	xp_init_xskb_addr(xskb, pool, i * pool->chunk_size);
2b43470a BT	108	}
2b43470a BT	109
7f7ffa4e	110	return pool;
2b43470a BT	111
	112	out:
	113	xp_destroy(pool);
	114	return NULL;
	115	}
	116
2b43470a BT	117	void xp_set_rxq_info(struct xsk_buff_pool pool, struct xdp_rxq_info rxq)
	118	{
	119	u32 i;
	120
	121	for (i = 0; i < pool->heads_cnt; i++)
	122	pool->heads[i].xdp.rxq = rxq;
	123	}
	124	EXPORT_SYMBOL(xp_set_rxq_info);
	125
921b6869 MK	126	static void xp_disable_drv_zc(struct xsk_buff_pool *pool)
	127	{
	128	struct netdev_bpf bpf;
	129	int err;
	130
	131	ASSERT_RTNL();
	132
	133	if (pool->umem->zc) {
	134	bpf.command = XDP_SETUP_XSK_POOL;
	135	bpf.xsk.pool = NULL;
	136	bpf.xsk.queue_id = pool->queue_id;
	137
	138	err = pool->netdev->netdev_ops->ndo_bpf(pool->netdev, &bpf);
	139
	140	if (err)
	141	WARN(1, "Failed to disable zero-copy!\n");
	142	}
	143	}
	144
0ae0cb2b MM	145	#define NETDEV_XDP_ACT_ZC (NETDEV_XDP_ACT_BASIC \| \
	146	NETDEV_XDP_ACT_REDIRECT \| \
	147	NETDEV_XDP_ACT_XSK_ZEROCOPY)
	148
f0863eab BT	149	int xp_assign_dev(struct xsk_buff_pool *pool,
f0863eab BT	150	struct net_device *netdev, u16 queue_id, u16 flags)
1c1efc2a	151	{
1c1efc2a MK	152	bool force_zc, force_copy;
	153	struct netdev_bpf bpf;
	154	int err = 0;
	155
	156	ASSERT_RTNL();
	157
	158	force_zc = flags & XDP_ZEROCOPY;
	159	force_copy = flags & XDP_COPY;
	160
	161	if (force_zc && force_copy)
	162	return -EINVAL;
	163
c2d3d6a4	164	if (xsk_get_pool_from_qid(netdev, queue_id))
1c1efc2a MK	165	return -EBUSY;
1c1efc2a MK	166
921b6869 MK	167	pool->netdev = netdev;
921b6869 MK	168	pool->queue_id = queue_id;
c2d3d6a4	169	err = xsk_reg_pool_at_qid(netdev, pool, queue_id);
1c1efc2a MK	170	if (err)
	171	return err;
	172
d609f3d2 TS	173	if (flags & XDP_USE_SG)
	174	pool->umem->flags \|= XDP_UMEM_SG_FLAG;
	175
e3920818	176	if (flags & XDP_USE_NEED_WAKEUP)
c2d3d6a4	177	pool->uses_need_wakeup = true;
e3920818 BT	178	/* Tx needs to be explicitly woken up the first time. Also
	179	* for supporting drivers that do not implement this
	180	* feature. They will always have to call sendto() or poll().
	181	*/
	182	pool->cached_need_wakeup = XDP_WAKEUP_TX;
1c1efc2a	183
c2d3d6a4 MK	184	dev_hold(netdev);
c2d3d6a4 MK	185
1c1efc2a MK	186	if (force_copy)
	187	/* For copy-mode, we are done. */
	188	return 0;
	189
0ae0cb2b	190	if ((netdev->xdp_features & NETDEV_XDP_ACT_ZC) != NETDEV_XDP_ACT_ZC) {
1c1efc2a MK	191	err = -EOPNOTSUPP;
	192	goto err_unreg_pool;
	193	}
	194
24ea5012 MF	195	if (netdev->xdp_zc_max_segs == 1 && (flags & XDP_USE_SG)) {
	196	err = -EOPNOTSUPP;
	197	goto err_unreg_pool;
	198	}
	199
1c1efc2a MK	200	bpf.command = XDP_SETUP_XSK_POOL;
	201	bpf.xsk.pool = pool;
	202	bpf.xsk.queue_id = queue_id;
	203
c2d3d6a4	204	err = netdev->netdev_ops->ndo_bpf(netdev, &bpf);
1c1efc2a MK	205	if (err)
	206	goto err_unreg_pool;
	207
921b6869 MK	208	if (!pool->dma_pages) {
921b6869 MK	209	WARN(1, "Driver did not DMA map zero-copy buffers");
12c8a8ca	210	err = -EINVAL;
921b6869 MK	211	goto err_unreg_xsk;
921b6869 MK	212	}
c2d3d6a4	213	pool->umem->zc = true;
1c1efc2a MK	214	return 0;
1c1efc2a MK	215
921b6869 MK	216	err_unreg_xsk:
921b6869 MK	217	xp_disable_drv_zc(pool);
1c1efc2a MK	218	err_unreg_pool:
	219	if (!force_zc)
	220	err = 0; /* fallback to copy mode */
17864891	221	if (err) {
c2d3d6a4	222	xsk_clear_pool_at_qid(netdev, queue_id);
17864891 MM	223	dev_put(netdev);
17864891 MM	224	}
1c1efc2a MK	225	return err;
	226	}
	227
60240bc2	228	int xp_assign_dev_shared(struct xsk_buff_pool pool, struct xdp_sock umem_xs,
b5aea28d MK	229	struct net_device *dev, u16 queue_id)
	230	{
	231	u16 flags;
60240bc2	232	struct xdp_umem *umem = umem_xs->umem;
b5aea28d MK	233
	234	/* One fill and completion ring required for each queue id. */
	235	if (!pool->fq \|\| !pool->cq)
	236	return -EINVAL;
	237
	238	flags = umem->zc ? XDP_ZEROCOPY : XDP_COPY;
60240bc2	239	if (umem_xs->pool->uses_need_wakeup)
b5aea28d MK	240	flags \|= XDP_USE_NEED_WAKEUP;
b5aea28d MK	241
f0863eab	242	return xp_assign_dev(pool, dev, queue_id, flags);
b5aea28d MK	243	}
b5aea28d MK	244
1c1efc2a MK	245	void xp_clear_dev(struct xsk_buff_pool *pool)
1c1efc2a MK	246	{
c2d3d6a4	247	if (!pool->netdev)
1c1efc2a MK	248	return;
1c1efc2a MK	249
921b6869	250	xp_disable_drv_zc(pool);
c2d3d6a4 MK	251	xsk_clear_pool_at_qid(pool->netdev, pool->queue_id);
	252	dev_put(pool->netdev);
	253	pool->netdev = NULL;
1c1efc2a MK	254	}
	255
	256	static void xp_release_deferred(struct work_struct *work)
	257	{
	258	struct xsk_buff_pool *pool = container_of(work, struct xsk_buff_pool,
	259	work);
	260
	261	rtnl_lock();
	262	xp_clear_dev(pool);
	263	rtnl_unlock();
	264
7361f9c3 MK	265	if (pool->fq) {
	266	xskq_destroy(pool->fq);
	267	pool->fq = NULL;
	268	}
	269
	270	if (pool->cq) {
	271	xskq_destroy(pool->cq);
	272	pool->cq = NULL;
	273	}
	274
537cf4e3	275	xdp_put_umem(pool->umem, false);
1c1efc2a MK	276	xp_destroy(pool);
	277	}
	278
	279	void xp_get_pool(struct xsk_buff_pool *pool)
	280	{
	281	refcount_inc(&pool->users);
	282	}
	283
e5e1a4bc	284	bool xp_put_pool(struct xsk_buff_pool *pool)
1c1efc2a MK	285	{
1c1efc2a MK	286	if (!pool)
e5e1a4bc	287	return false;
1c1efc2a MK	288
	289	if (refcount_dec_and_test(&pool->users)) {
	290	INIT_WORK(&pool->work, xp_release_deferred);
	291	schedule_work(&pool->work);
e5e1a4bc	292	return true;
1c1efc2a	293	}
e5e1a4bc MK	294
e5e1a4bc MK	295	return false;
1c1efc2a MK	296	}
1c1efc2a MK	297
921b6869 MK	298	static struct xsk_dma_map xp_find_dma_map(struct xsk_buff_pool pool)
	299	{
	300	struct xsk_dma_map *dma_map;
	301
	302	list_for_each_entry(dma_map, &pool->umem->xsk_dma_list, list) {
	303	if (dma_map->netdev == pool->netdev)
	304	return dma_map;
	305	}
	306
	307	return NULL;
	308	}
	309
	310	static struct xsk_dma_map xp_create_dma_map(struct device dev, struct net_device *netdev,
	311	u32 nr_pages, struct xdp_umem *umem)
	312	{
	313	struct xsk_dma_map *dma_map;
	314
	315	dma_map = kzalloc(sizeof(*dma_map), GFP_KERNEL);
	316	if (!dma_map)
	317	return NULL;
	318
	319	dma_map->dma_pages = kvcalloc(nr_pages, sizeof(*dma_map->dma_pages), GFP_KERNEL);
1d6fd78a	320	if (!dma_map->dma_pages) {
921b6869 MK	321	kfree(dma_map);
	322	return NULL;
	323	}
	324
	325	dma_map->netdev = netdev;
	326	dma_map->dev = dev;
	327	dma_map->dma_need_sync = false;
	328	dma_map->dma_pages_cnt = nr_pages;
bf74a370	329	refcount_set(&dma_map->users, 1);
921b6869 MK	330	list_add(&dma_map->list, &umem->xsk_dma_list);
	331	return dma_map;
	332	}
	333
	334	static void xp_destroy_dma_map(struct xsk_dma_map *dma_map)
	335	{
	336	list_del(&dma_map->list);
	337	kvfree(dma_map->dma_pages);
	338	kfree(dma_map);
	339	}
	340
	341	static void __xp_dma_unmap(struct xsk_dma_map *dma_map, unsigned long attrs)
2b43470a BT	342	{
	343	dma_addr_t *dma;
	344	u32 i;
	345
921b6869 MK	346	for (i = 0; i < dma_map->dma_pages_cnt; i++) {
921b6869 MK	347	dma = &dma_map->dma_pages[i];
2b43470a	348	if (*dma) {
512d1999	349	*dma &= ~XSK_NEXT_PG_CONTIG_MASK;
921b6869	350	dma_unmap_page_attrs(dma_map->dev, *dma, PAGE_SIZE,
2b43470a BT	351	DMA_BIDIRECTIONAL, attrs);
	352	*dma = 0;
	353	}
	354	}
	355
921b6869 MK	356	xp_destroy_dma_map(dma_map);
	357	}
	358
	359	void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs)
	360	{
	361	struct xsk_dma_map *dma_map;
	362
6ec7be9a	363	if (!pool->dma_pages)
921b6869 MK	364	return;
	365
	366	dma_map = xp_find_dma_map(pool);
	367	if (!dma_map) {
	368	WARN(1, "Could not find dma_map for device");
	369	return;
	370	}
	371
	372	if (!refcount_dec_and_test(&dma_map->users))
	373	return;
	374
	375	__xp_dma_unmap(dma_map, attrs);
2b43470a	376	kvfree(pool->dma_pages);
6ec7be9a	377	pool->dma_pages = NULL;
2b43470a BT	378	pool->dma_pages_cnt = 0;
	379	pool->dev = NULL;
	380	}
	381	EXPORT_SYMBOL(xp_dma_unmap);
	382
921b6869	383	static void xp_check_dma_contiguity(struct xsk_dma_map *dma_map)
2b43470a BT	384	{
	385	u32 i;
	386
921b6869 MK	387	for (i = 0; i < dma_map->dma_pages_cnt - 1; i++) {
	388	if (dma_map->dma_pages[i] + PAGE_SIZE == dma_map->dma_pages[i + 1])
	389	dma_map->dma_pages[i] \|= XSK_NEXT_PG_CONTIG_MASK;
2b43470a	390	else
921b6869	391	dma_map->dma_pages[i] &= ~XSK_NEXT_PG_CONTIG_MASK;
2b43470a BT	392	}
	393	}
	394
921b6869 MK	395	static int xp_init_dma_info(struct xsk_buff_pool pool, struct xsk_dma_map dma_map)
921b6869 MK	396	{
58ca14ed MK	397	if (!pool->unaligned) {
	398	u32 i;
	399
	400	for (i = 0; i < pool->heads_cnt; i++) {
	401	struct xdp_buff_xsk *xskb = &pool->heads[i];
	402
	403	xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, xskb->orig_addr);
	404	}
	405	}
	406
921b6869 MK	407	pool->dma_pages = kvcalloc(dma_map->dma_pages_cnt, sizeof(*pool->dma_pages), GFP_KERNEL);
	408	if (!pool->dma_pages)
	409	return -ENOMEM;
	410
	411	pool->dev = dma_map->dev;
	412	pool->dma_pages_cnt = dma_map->dma_pages_cnt;
	413	pool->dma_need_sync = dma_map->dma_need_sync;
921b6869 MK	414	memcpy(pool->dma_pages, dma_map->dma_pages,
	415	pool->dma_pages_cnt * sizeof(*pool->dma_pages));
	416
	417	return 0;
	418	}
	419
2b43470a BT	420	int xp_dma_map(struct xsk_buff_pool pool, struct device dev,
	421	unsigned long attrs, struct page **pages, u32 nr_pages)
	422	{
921b6869	423	struct xsk_dma_map *dma_map;
2b43470a	424	dma_addr_t dma;
921b6869	425	int err;
2b43470a BT	426	u32 i;
2b43470a BT	427
921b6869 MK	428	dma_map = xp_find_dma_map(pool);
	429	if (dma_map) {
	430	err = xp_init_dma_info(pool, dma_map);
	431	if (err)
	432	return err;
2b43470a	433
bf74a370	434	refcount_inc(&dma_map->users);
921b6869 MK	435	return 0;
921b6869 MK	436	}
2b43470a	437
921b6869 MK	438	dma_map = xp_create_dma_map(dev, pool->netdev, nr_pages, pool->umem);
	439	if (!dma_map)
	440	return -ENOMEM;
	441
	442	for (i = 0; i < dma_map->dma_pages_cnt; i++) {
2b43470a BT	443	dma = dma_map_page_attrs(dev, pages[i], 0, PAGE_SIZE,
	444	DMA_BIDIRECTIONAL, attrs);
	445	if (dma_mapping_error(dev, dma)) {
921b6869	446	__xp_dma_unmap(dma_map, attrs);
2b43470a BT	447	return -ENOMEM;
2b43470a BT	448	}
7e024575	449	if (dma_need_sync(dev, dma))
921b6869 MK	450	dma_map->dma_need_sync = true;
921b6869 MK	451	dma_map->dma_pages[i] = dma;
2b43470a BT	452	}
	453
	454	if (pool->unaligned)
921b6869 MK	455	xp_check_dma_contiguity(dma_map);
	456
	457	err = xp_init_dma_info(pool, dma_map);
	458	if (err) {
	459	__xp_dma_unmap(dma_map, attrs);
	460	return err;
	461	}
	462
2b43470a BT	463	return 0;
	464	}
	465	EXPORT_SYMBOL(xp_dma_map);
	466
2b43470a BT	467	static bool xp_addr_crosses_non_contig_pg(struct xsk_buff_pool *pool,
	468	u64 addr)
	469	{
	470	return xp_desc_crosses_non_contig_pg(pool, addr, pool->chunk_size);
	471	}
	472
2b43470a BT	473	static bool xp_check_unaligned(struct xsk_buff_pool pool, u64 addr)
	474	{
	475	addr = xp_unaligned_extract_addr(addr);
	476	if (*addr >= pool->addrs_cnt \|\|
	477	*addr + pool->chunk_size > pool->addrs_cnt \|\|
	478	xp_addr_crosses_non_contig_pg(pool, *addr))
	479	return false;
	480	return true;
	481	}
	482
	483	static bool xp_check_aligned(struct xsk_buff_pool pool, u64 addr)
	484	{
	485	addr = xp_aligned_extract_addr(pool, addr);
	486	return *addr < pool->addrs_cnt;
	487	}
	488
	489	static struct xdp_buff_xsk __xp_alloc(struct xsk_buff_pool pool)
	490	{
	491	struct xdp_buff_xsk *xskb;
	492	u64 addr;
	493	bool ok;
	494
	495	if (pool->free_heads_cnt == 0)
	496	return NULL;
	497
2b43470a BT	498	for (;;) {
2b43470a BT	499	if (!xskq_cons_peek_addr_unchecked(pool->fq, &addr)) {
8aa5a335	500	pool->fq->queue_empty_descs++;
2b43470a BT	501	return NULL;
	502	}
	503
	504	ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
	505	xp_check_aligned(pool, &addr);
	506	if (!ok) {
	507	pool->fq->invalid_descs++;
	508	xskq_cons_release(pool->fq);
	509	continue;
	510	}
	511	break;
	512	}
2b43470a	513
94033cd8 MK	514	if (pool->unaligned) {
	515	xskb = pool->free_heads[--pool->free_heads_cnt];
	516	xp_init_xskb_addr(xskb, pool, addr);
6ec7be9a	517	if (pool->dma_pages)
94033cd8 MK	518	xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr);
	519	} else {
	520	xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)];
2b43470a	521	}
94033cd8 MK	522
94033cd8 MK	523	xskq_cons_release(pool->fq);
2b43470a BT	524	return xskb;
	525	}
	526
	527	struct xdp_buff xp_alloc(struct xsk_buff_pool pool)
	528	{
	529	struct xdp_buff_xsk *xskb;
	530
	531	if (!pool->free_list_cnt) {
	532	xskb = __xp_alloc(pool);
	533	if (!xskb)
	534	return NULL;
	535	} else {
	536	pool->free_list_cnt--;
	537	xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk,
	538	free_list_node);
199d983b	539	list_del_init(&xskb->free_list_node);
2b43470a BT	540	}
	541
	542	xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM;
	543	xskb->xdp.data_meta = xskb->xdp.data;
	544
91d5b702	545	if (pool->dma_need_sync) {
2b43470a BT	546	dma_sync_single_range_for_device(pool->dev, xskb->dma, 0,
	547	pool->frame_len,
	548	DMA_BIDIRECTIONAL);
	549	}
	550	return &xskb->xdp;
	551	}
	552	EXPORT_SYMBOL(xp_alloc);
	553
47e4075d MK	554	static u32 xp_alloc_new_from_fq(struct xsk_buff_pool pool, struct xdp_buff *xdp, u32 max)
	555	{
	556	u32 i, cached_cons, nb_entries;
	557
	558	if (max > pool->free_heads_cnt)
	559	max = pool->free_heads_cnt;
	560	max = xskq_cons_nb_entries(pool->fq, max);
	561
	562	cached_cons = pool->fq->cached_cons;
	563	nb_entries = max;
	564	i = max;
	565	while (i--) {
	566	struct xdp_buff_xsk *xskb;
	567	u64 addr;
	568	bool ok;
	569
	570	__xskq_cons_read_addr_unchecked(pool->fq, cached_cons++, &addr);
	571
	572	ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
	573	xp_check_aligned(pool, &addr);
	574	if (unlikely(!ok)) {
	575	pool->fq->invalid_descs++;
	576	nb_entries--;
	577	continue;
	578	}
	579
94033cd8 MK	580	if (pool->unaligned) {
	581	xskb = pool->free_heads[--pool->free_heads_cnt];
	582	xp_init_xskb_addr(xskb, pool, addr);
6ec7be9a	583	if (pool->dma_pages)
94033cd8 MK	584	xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr);
	585	} else {
	586	xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)];
	587	}
	588
47e4075d	589	*xdp = &xskb->xdp;
47e4075d MK	590	xdp++;
	591	}
	592
	593	xskq_cons_release_n(pool->fq, max);
	594	return nb_entries;
	595	}
	596
	597	static u32 xp_alloc_reused(struct xsk_buff_pool pool, struct xdp_buff *xdp, u32 nb_entries)
	598	{
	599	struct xdp_buff_xsk *xskb;
	600	u32 i;
	601
	602	nb_entries = min_t(u32, nb_entries, pool->free_list_cnt);
	603
	604	i = nb_entries;
	605	while (i--) {
	606	xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk, free_list_node);
199d983b	607	list_del_init(&xskb->free_list_node);
47e4075d MK	608
	609	*xdp = &xskb->xdp;
	610	xdp++;
	611	}
	612	pool->free_list_cnt -= nb_entries;
	613
	614	return nb_entries;
	615	}
	616
	617	u32 xp_alloc_batch(struct xsk_buff_pool pool, struct xdp_buff *xdp, u32 max)
	618	{
	619	u32 nb_entries1 = 0, nb_entries2;
	620
	621	if (unlikely(pool->dma_need_sync)) {
a95a4d9b MK	622	struct xdp_buff *buff;
a95a4d9b MK	623
47e4075d	624	/* Slow path */
a95a4d9b MK	625	buff = xp_alloc(pool);
	626	if (buff)
	627	*xdp = buff;
	628	return !!buff;
47e4075d MK	629	}
	630
	631	if (unlikely(pool->free_list_cnt)) {
	632	nb_entries1 = xp_alloc_reused(pool, xdp, max);
	633	if (nb_entries1 == max)
	634	return nb_entries1;
	635
	636	max -= nb_entries1;
	637	xdp += nb_entries1;
	638	}
	639
	640	nb_entries2 = xp_alloc_new_from_fq(pool, xdp, max);
	641	if (!nb_entries2)
	642	pool->fq->queue_empty_descs++;
	643
	644	return nb_entries1 + nb_entries2;
	645	}
	646	EXPORT_SYMBOL(xp_alloc_batch);
	647
2b43470a BT	648	bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count)
	649	{
	650	if (pool->free_list_cnt >= count)
	651	return true;
	652	return xskq_cons_has_entries(pool->fq, count - pool->free_list_cnt);
	653	}
	654	EXPORT_SYMBOL(xp_can_alloc);
	655
	656	void xp_free(struct xdp_buff_xsk *xskb)
	657	{
199d983b MK	658	if (!list_empty(&xskb->free_list_node))
	659	return;
	660
2b43470a BT	661	xskb->pool->free_list_cnt++;
	662	list_add(&xskb->free_list_node, &xskb->pool->free_list);
	663	}
	664	EXPORT_SYMBOL(xp_free);
	665
2b43470a BT	666	void xp_raw_get_data(struct xsk_buff_pool pool, u64 addr)
	667	{
	668	addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
	669	return pool->addrs + addr;
	670	}
	671	EXPORT_SYMBOL(xp_raw_get_data);
	672
	673	dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
	674	{
	675	addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
	676	return (pool->dma_pages[addr >> PAGE_SHIFT] &
	677	~XSK_NEXT_PG_CONTIG_MASK) +
	678	(addr & ~PAGE_MASK);
	679	}
	680	EXPORT_SYMBOL(xp_raw_get_dma);
	681
26062b18	682	void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb)
2b43470a	683	{
2b43470a BT	684	dma_sync_single_range_for_cpu(xskb->pool->dev, xskb->dma, 0,
	685	xskb->pool->frame_len, DMA_BIDIRECTIONAL);
	686	}
26062b18	687	EXPORT_SYMBOL(xp_dma_sync_for_cpu_slow);
2b43470a	688
26062b18 BT	689	void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma,
26062b18 BT	690	size_t size)
2b43470a	691	{
2b43470a BT	692	dma_sync_single_range_for_device(pool->dev, dma, 0,
	693	size, DMA_BIDIRECTIONAL);
	694	}
26062b18	695	EXPORT_SYMBOL(xp_dma_sync_for_device_slow);