1 files changed, 113 insertions, 61 deletions

diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c
index ce60ecd48a4d..aa9788f20d0d 100644
--- a/net/xdp/xsk_buff_pool.c
+++ b/net/xdp/xsk_buff_pool.c
@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
+#include <linux/netdevice.h>
+#include <net/netdev_lock.h>
 #include <net/xsk_buff_pool.h>
 #include <net/xdp_sock.h>
 #include <net/xdp_sock_drv.h>
@@ -87,6 +89,7 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
 	pool->addrs = umem->addrs;
 	pool->tx_metadata_len = umem->tx_metadata_len;
 	pool->tx_sw_csum = umem->flags & XDP_UMEM_TX_SW_CSUM;
+	spin_lock_init(&pool->rx_lock);
 	INIT_LIST_HEAD(&pool->free_list);
 	INIT_LIST_HEAD(&pool->xskb_list);
 	INIT_LIST_HEAD(&pool->xsk_tx_list);
@@ -101,12 +104,11 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
 		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);
+		INIT_LIST_HEAD(&xskb->list_node);
 		if (pool->unaligned)
 			pool->free_heads[i] = xskb;
 		else
-			xp_init_xskb_addr(xskb, pool, i * pool->chunk_size);
+			xp_init_xskb_addr(xskb, pool, (u64)i * pool->chunk_size);
 	}
 
 	return pool;
@@ -211,10 +213,16 @@ int xp_assign_dev(struct xsk_buff_pool *pool,
 		goto err_unreg_pool;
 	}
 
+	if (dev_get_min_mp_channel_count(netdev)) {
+		err = -EBUSY;
+		goto err_unreg_pool;
+	}
+
 	bpf.command = XDP_SETUP_XSK_POOL;
 	bpf.xsk.pool = pool;
 	bpf.xsk.queue_id = queue_id;
 
+	netdev_ops_assert_locked(netdev);
 	err = netdev->netdev_ops->ndo_bpf(netdev, &bpf);
 	if (err)
 		goto err_unreg_pool;
@@ -225,6 +233,7 @@ int xp_assign_dev(struct xsk_buff_pool *pool,
 		goto err_unreg_xsk;
 	}
 	pool->umem->zc = true;
+	pool->xdp_zc_max_segs = netdev->xdp_zc_max_segs;
 	return 0;
 
 err_unreg_xsk:
@@ -258,13 +267,17 @@ int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs,
 
 void xp_clear_dev(struct xsk_buff_pool *pool)
 {
+	struct net_device *netdev = pool->netdev;
+
 	if (!pool->netdev)
 		return;
 
+	netdev_lock_ops(netdev);
 	xp_disable_drv_zc(pool);
 	xsk_clear_pool_at_qid(pool->netdev, pool->queue_id);
-	dev_put(pool->netdev);
 	pool->netdev = NULL;
+	netdev_unlock_ops(netdev);
+	dev_put(netdev);
 }
 
 static void xp_release_deferred(struct work_struct *work)
@@ -338,7 +351,6 @@ static struct xsk_dma_map *xp_create_dma_map(struct device *dev, struct net_devi
 
 	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);
@@ -383,10 +395,9 @@ void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs)
 		return;
 	}
 
-	if (!refcount_dec_and_test(&dma_map->users))
-		return;
+	if (refcount_dec_and_test(&dma_map->users))
+		__xp_dma_unmap(dma_map, attrs);
 
-	__xp_dma_unmap(dma_map, attrs);
 	kvfree(pool->dma_pages);
 	pool->dma_pages = NULL;
 	pool->dma_pages_cnt = 0;
@@ -413,8 +424,10 @@ static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_
 
 		for (i = 0; i < pool->heads_cnt; i++) {
 			struct xdp_buff_xsk *xskb = &pool->heads[i];
+			u64 orig_addr;
 
-			xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, xskb->orig_addr);
+			orig_addr = xskb->xdp.data_hard_start - pool->addrs - pool->headroom;
+			xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, orig_addr);
 		}
 	}
 
@@ -424,7 +437,6 @@ static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_
 
 	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));
 
@@ -460,8 +472,6 @@ int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
 			__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;
 	}
 
@@ -500,6 +510,22 @@ static bool xp_check_aligned(struct xsk_buff_pool *pool, u64 *addr)
 	return *addr < pool->addrs_cnt;
 }
 
+static struct xdp_buff_xsk *xp_get_xskb(struct xsk_buff_pool *pool, u64 addr)
+{
+	struct xdp_buff_xsk *xskb;
+
+	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)];
+	}
+
+	return xskb;
+}
+
 static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool)
 {
 	struct xdp_buff_xsk *xskb;
@@ -525,14 +551,7 @@ static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool)
 		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)];
-	}
+	xskb = xp_get_xskb(pool, addr);
 
 	xskq_cons_release(pool->fq);
 	return xskb;
@@ -549,19 +568,17 @@ struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool)
 	} 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);
+					list_node);
+		list_del_init(&xskb->list_node);
 	}
 
 	xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM;
 	xskb->xdp.data_meta = xskb->xdp.data;
 	xskb->xdp.flags = 0;
 
-	if (pool->dma_need_sync) {
-		dma_sync_single_range_for_device(pool->dev, xskb->dma, 0,
-						 pool->frame_len,
-						 DMA_BIDIRECTIONAL);
-	}
+	if (pool->dev)
+		xp_dma_sync_for_device(pool, xskb->dma, pool->frame_len);
+
 	return &xskb->xdp;
 }
 EXPORT_SYMBOL(xp_alloc);
@@ -592,14 +609,7 @@ static u32 xp_alloc_new_from_fq(struct xsk_buff_pool *pool, struct xdp_buff **xd
 			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)];
-		}
+		xskb = xp_get_xskb(pool, addr);
 
 		*xdp = &xskb->xdp;
 		xdp++;
@@ -618,8 +628,8 @@ static u32 xp_alloc_reused(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u3
 
 	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);
+		xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk, list_node);
+		list_del_init(&xskb->list_node);
 
 		*xdp = &xskb->xdp;
 		xdp++;
@@ -629,20 +639,31 @@ static u32 xp_alloc_reused(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u3
 	return nb_entries;
 }
 
-u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
+static u32 xp_alloc_slow(struct xsk_buff_pool *pool, struct xdp_buff **xdp,
+			 u32 max)
 {
-	u32 nb_entries1 = 0, nb_entries2;
+	int i;
 
-	if (unlikely(pool->dma_need_sync)) {
+	for (i = 0; i < max; i++) {
 		struct xdp_buff *buff;
 
-		/* Slow path */
 		buff = xp_alloc(pool);
-		if (buff)
-			*xdp = buff;
-		return !!buff;
+		if (unlikely(!buff))
+			return i;
+		*xdp = buff;
+		xdp++;
 	}
 
+	return max;
+}
+
+u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
+{
+	u32 nb_entries1 = 0, nb_entries2;
+
+	if (unlikely(pool->dev && dma_dev_need_sync(pool->dev)))
+		return xp_alloc_slow(pool, xdp, max);
+
 	if (unlikely(pool->free_list_cnt)) {
 		nb_entries1 = xp_alloc_reused(pool, xdp, max);
 		if (nb_entries1 == max)
@@ -662,49 +683,80 @@ EXPORT_SYMBOL(xp_alloc_batch);
 
 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count)
 {
+	u32 req_count, avail_count;
+
 	if (pool->free_list_cnt >= count)
 		return true;
-	return xskq_cons_has_entries(pool->fq, count - pool->free_list_cnt);
+
+	req_count = count - pool->free_list_cnt;
+	avail_count = xskq_cons_nb_entries(pool->fq, req_count);
+	if (!avail_count)
+		pool->fq->queue_empty_descs++;
+
+	return avail_count >= req_count;
 }
 EXPORT_SYMBOL(xp_can_alloc);
 
 void xp_free(struct xdp_buff_xsk *xskb)
 {
-	if (!list_empty(&xskb->free_list_node))
+	if (!list_empty(&xskb->list_node))
 		return;
 
 	xskb->pool->free_list_cnt++;
-	list_add(&xskb->free_list_node, &xskb->pool->free_list);
+	list_add(&xskb->list_node, &xskb->pool->free_list);
 }
 EXPORT_SYMBOL(xp_free);
 
-void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
+static u64 __xp_raw_get_addr(const struct xsk_buff_pool *pool, u64 addr)
+{
+	return pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
+}
+
+static void *__xp_raw_get_data(const struct xsk_buff_pool *pool, u64 addr)
 {
-	addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
 	return pool->addrs + addr;
 }
+
+void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
+{
+	return __xp_raw_get_data(pool, __xp_raw_get_addr(pool, addr));
+}
 EXPORT_SYMBOL(xp_raw_get_data);
 
-dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
+static dma_addr_t __xp_raw_get_dma(const 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_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
 {
-	dma_sync_single_range_for_cpu(xskb->pool->dev, xskb->dma, 0,
-				      xskb->pool->frame_len, DMA_BIDIRECTIONAL);
+	return __xp_raw_get_dma(pool, __xp_raw_get_addr(pool, addr));
 }
-EXPORT_SYMBOL(xp_dma_sync_for_cpu_slow);
+EXPORT_SYMBOL(xp_raw_get_dma);
 
-void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma,
-				 size_t size)
+/**
+ * xp_raw_get_ctx - get &xdp_desc context
+ * @pool: XSk buff pool desc address belongs to
+ * @addr: desc address (from userspace)
+ *
+ * Helper for getting desc's DMA address and metadata pointer, if present.
+ * Saves one call on hotpath, double calculation of the actual address,
+ * and inline checks for metadata presence and sanity.
+ *
+ * Return: new &xdp_desc_ctx struct containing desc's DMA address and metadata
+ * pointer, if it is present and valid (initialized to %NULL otherwise).
+ */
+struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr)
 {
-	dma_sync_single_range_for_device(pool->dev, dma, 0,
-					 size, DMA_BIDIRECTIONAL);
+	struct xdp_desc_ctx ret;
+
+	addr = __xp_raw_get_addr(pool, addr);
+
+	ret.dma = __xp_raw_get_dma(pool, addr);
+	ret.meta = __xsk_buff_get_metadata(pool, __xp_raw_get_data(pool, addr));
+
+	return ret;
 }
-EXPORT_SYMBOL(xp_dma_sync_for_device_slow);
+EXPORT_SYMBOL(xp_raw_get_ctx);