1 files changed, 187 insertions, 81 deletions

diff --git a/net/core/devmem.c b/net/core/devmem.c
index 11b91c12ee11..b3a62ca0df65 100644
--- a/net/core/devmem.c
+++ b/net/core/devmem.c
@@ -15,6 +15,8 @@
 #include <net/netdev_queues.h>
 #include <net/netdev_rx_queue.h>
 #include <net/page_pool/helpers.h>
+#include <net/page_pool/memory_provider.h>
+#include <net/sock.h>
 #include <trace/events/page_pool.h>
 
 #include "devmem.h"
@@ -23,29 +25,38 @@
 
 /* Device memory support */
 
-/* Protected by rtnl_lock() */
 static DEFINE_XARRAY_FLAGS(net_devmem_dmabuf_bindings, XA_FLAGS_ALLOC1);
 
+static const struct memory_provider_ops dmabuf_devmem_ops;
+
+bool net_is_devmem_iov(struct net_iov *niov)
+{
+	return niov->type == NET_IOV_DMABUF;
+}
+
 static void net_devmem_dmabuf_free_chunk_owner(struct gen_pool *genpool,
 					       struct gen_pool_chunk *chunk,
 					       void *not_used)
 {
 	struct dmabuf_genpool_chunk_owner *owner = chunk->owner;
 
-	kvfree(owner->niovs);
+	kvfree(owner->area.niovs);
 	kfree(owner);
 }
 
 static dma_addr_t net_devmem_get_dma_addr(const struct net_iov *niov)
 {
-	struct dmabuf_genpool_chunk_owner *owner = net_iov_owner(niov);
+	struct dmabuf_genpool_chunk_owner *owner;
 
+	owner = net_devmem_iov_to_chunk_owner(niov);
 	return owner->base_dma_addr +
 	       ((dma_addr_t)net_iov_idx(niov) << PAGE_SHIFT);
 }
 
-void __net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding)
+void __net_devmem_dmabuf_binding_free(struct work_struct *wq)
 {
+	struct net_devmem_dmabuf_binding *binding = container_of(wq, typeof(*binding), unbind_w);
+
 	size_t size, avail;
 
 	gen_pool_for_each_chunk(binding->chunk_pool,
@@ -63,8 +74,10 @@ void __net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding)
 	dma_buf_detach(binding->dmabuf, binding->attachment);
 	dma_buf_put(binding->dmabuf);
 	xa_destroy(&binding->bound_rxqs);
+	kvfree(binding->tx_vec);
 	kfree(binding);
 }
+EXPORT_SYMBOL(__net_devmem_dmabuf_binding_free);
 
 struct net_iov *
 net_devmem_alloc_dmabuf(struct net_devmem_dmabuf_binding *binding)
@@ -82,7 +95,7 @@ net_devmem_alloc_dmabuf(struct net_devmem_dmabuf_binding *binding)
 
 	offset = dma_addr - owner->base_dma_addr;
 	index = offset / PAGE_SIZE;
-	niov = &owner->niovs[index];
+	niov = &owner->area.niovs[index];
 
 	niov->pp_magic = 0;
 	niov->pp = NULL;
@@ -93,7 +106,7 @@ net_devmem_alloc_dmabuf(struct net_devmem_dmabuf_binding *binding)
 
 void net_devmem_free_dmabuf(struct net_iov *niov)
 {
-	struct net_devmem_dmabuf_binding *binding = net_iov_binding(niov);
+	struct net_devmem_dmabuf_binding *binding = net_devmem_iov_binding(niov);
 	unsigned long dma_addr = net_devmem_get_dma_addr(niov);
 
 	if (WARN_ON(!gen_pool_has_addr(binding->chunk_pool, dma_addr,
@@ -109,21 +122,27 @@ void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding)
 	unsigned long xa_idx;
 	unsigned int rxq_idx;
 
+	xa_erase(&net_devmem_dmabuf_bindings, binding->id);
+
+	/* Ensure no tx net_devmem_lookup_dmabuf() are in flight after the
+	 * erase.
+	 */
+	synchronize_net();
+
 	if (binding->list.next)
 		list_del(&binding->list);
 
 	xa_for_each(&binding->bound_rxqs, xa_idx, rxq) {
-		WARN_ON(rxq->mp_params.mp_priv != binding);
-
-		rxq->mp_params.mp_priv = NULL;
+		const struct pp_memory_provider_params mp_params = {
+			.mp_priv	= binding,
+			.mp_ops		= &dmabuf_devmem_ops,
+		};
 
 		rxq_idx = get_netdev_rx_queue_index(rxq);
 
-		WARN_ON(netdev_rx_queue_restart(binding->dev, rxq_idx));
+		__net_mp_close_rxq(binding->dev, rxq_idx, &mp_params);
 	}
 
-	xa_erase(&net_devmem_dmabuf_bindings, binding->id);
-
 	net_devmem_dmabuf_binding_put(binding);
 }
 
@@ -131,50 +150,35 @@ int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
 				    struct net_devmem_dmabuf_binding *binding,
 				    struct netlink_ext_ack *extack)
 {
+	struct pp_memory_provider_params mp_params = {
+		.mp_priv	= binding,
+		.mp_ops		= &dmabuf_devmem_ops,
+	};
 	struct netdev_rx_queue *rxq;
 	u32 xa_idx;
 	int err;
 
-	if (rxq_idx >= dev->real_num_rx_queues) {
-		NL_SET_ERR_MSG(extack, "rx queue index out of range");
-		return -ERANGE;
-	}
+	err = __net_mp_open_rxq(dev, rxq_idx, &mp_params, extack);
+	if (err)
+		return err;
 
 	rxq = __netif_get_rx_queue(dev, rxq_idx);
-	if (rxq->mp_params.mp_priv) {
-		NL_SET_ERR_MSG(extack, "designated queue already memory provider bound");
-		return -EEXIST;
-	}
-
-#ifdef CONFIG_XDP_SOCKETS
-	if (rxq->pool) {
-		NL_SET_ERR_MSG(extack, "designated queue already in use by AF_XDP");
-		return -EBUSY;
-	}
-#endif
-
 	err = xa_alloc(&binding->bound_rxqs, &xa_idx, rxq, xa_limit_32b,
 		       GFP_KERNEL);
 	if (err)
-		return err;
-
-	rxq->mp_params.mp_priv = binding;
-
-	err = netdev_rx_queue_restart(dev, rxq_idx);
-	if (err)
-		goto err_xa_erase;
+		goto err_close_rxq;
 
 	return 0;
 
-err_xa_erase:
-	rxq->mp_params.mp_priv = NULL;
-	xa_erase(&binding->bound_rxqs, xa_idx);
-
+err_close_rxq:
+	__net_mp_close_rxq(dev, rxq_idx, &mp_params);
 	return err;
 }
 
 struct net_devmem_dmabuf_binding *
-net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd,
+net_devmem_bind_dmabuf(struct net_device *dev,
+		       enum dma_data_direction direction,
+		       unsigned int dmabuf_fd, struct netdev_nl_sock *priv,
 		       struct netlink_ext_ack *extack)
 {
 	struct net_devmem_dmabuf_binding *binding;
@@ -197,43 +201,48 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd,
 	}
 
 	binding->dev = dev;
-
-	err = xa_alloc_cyclic(&net_devmem_dmabuf_bindings, &binding->id,
-			      binding, xa_limit_32b, &id_alloc_next,
-			      GFP_KERNEL);
-	if (err < 0)
-		goto err_free_binding;
-
 	xa_init_flags(&binding->bound_rxqs, XA_FLAGS_ALLOC);
 
 	refcount_set(&binding->ref, 1);
 
+	mutex_init(&binding->lock);
+
 	binding->dmabuf = dmabuf;
 
 	binding->attachment = dma_buf_attach(binding->dmabuf, dev->dev.parent);
 	if (IS_ERR(binding->attachment)) {
 		err = PTR_ERR(binding->attachment);
 		NL_SET_ERR_MSG(extack, "Failed to bind dmabuf to device");
-		goto err_free_id;
+		goto err_free_binding;
 	}
 
 	binding->sgt = dma_buf_map_attachment_unlocked(binding->attachment,
-						       DMA_FROM_DEVICE);
+						       direction);
 	if (IS_ERR(binding->sgt)) {
 		err = PTR_ERR(binding->sgt);
 		NL_SET_ERR_MSG(extack, "Failed to map dmabuf attachment");
 		goto err_detach;
 	}
 
+	if (direction == DMA_TO_DEVICE) {
+		binding->tx_vec = kvmalloc_array(dmabuf->size / PAGE_SIZE,
+						 sizeof(struct net_iov *),
+						 GFP_KERNEL);
+		if (!binding->tx_vec) {
+			err = -ENOMEM;
+			goto err_unmap;
+		}
+	}
+
 	/* For simplicity we expect to make PAGE_SIZE allocations, but the
 	 * binding can be much more flexible than that. We may be able to
 	 * allocate MTU sized chunks here. Leave that for future work...
 	 */
-	binding->chunk_pool =
-		gen_pool_create(PAGE_SHIFT, dev_to_node(&dev->dev));
+	binding->chunk_pool = gen_pool_create(PAGE_SHIFT,
+					      dev_to_node(&dev->dev));
 	if (!binding->chunk_pool) {
 		err = -ENOMEM;
-		goto err_unmap;
+		goto err_tx_vec;
 	}
 
 	virtual = 0;
@@ -250,9 +259,9 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd,
 			goto err_free_chunks;
 		}
 
-		owner->base_virtual = virtual;
+		owner->area.base_virtual = virtual;
 		owner->base_dma_addr = dma_addr;
-		owner->num_niovs = len / PAGE_SIZE;
+		owner->area.num_niovs = len / PAGE_SIZE;
 		owner->binding = binding;
 
 		err = gen_pool_add_owner(binding->chunk_pool, dma_addr,
@@ -264,37 +273,48 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd,
 			goto err_free_chunks;
 		}
 
-		owner->niovs = kvmalloc_array(owner->num_niovs,
-					      sizeof(*owner->niovs),
-					      GFP_KERNEL);
-		if (!owner->niovs) {
+		owner->area.niovs = kvmalloc_array(owner->area.num_niovs,
+						   sizeof(*owner->area.niovs),
+						   GFP_KERNEL);
+		if (!owner->area.niovs) {
 			err = -ENOMEM;
 			goto err_free_chunks;
 		}
 
-		for (i = 0; i < owner->num_niovs; i++) {
-			niov = &owner->niovs[i];
-			niov->owner = owner;
+		for (i = 0; i < owner->area.num_niovs; i++) {
+			niov = &owner->area.niovs[i];
+			niov->type = NET_IOV_DMABUF;
+			niov->owner = &owner->area;
 			page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov),
 						      net_devmem_get_dma_addr(niov));
+			if (direction == DMA_TO_DEVICE)
+				binding->tx_vec[owner->area.base_virtual / PAGE_SIZE + i] = niov;
 		}
 
 		virtual += len;
 	}
 
+	err = xa_alloc_cyclic(&net_devmem_dmabuf_bindings, &binding->id,
+			      binding, xa_limit_32b, &id_alloc_next,
+			      GFP_KERNEL);
+	if (err < 0)
+		goto err_free_chunks;
+
+	list_add(&binding->list, &priv->bindings);
+
 	return binding;
 
 err_free_chunks:
 	gen_pool_for_each_chunk(binding->chunk_pool,
 				net_devmem_dmabuf_free_chunk_owner, NULL);
 	gen_pool_destroy(binding->chunk_pool);
+err_tx_vec:
+	kvfree(binding->tx_vec);
 err_unmap:
 	dma_buf_unmap_attachment_unlocked(binding->attachment, binding->sgt,
 					  DMA_FROM_DEVICE);
 err_detach:
 	dma_buf_detach(dmabuf, binding->attachment);
-err_free_id:
-	xa_erase(&net_devmem_dmabuf_bindings, binding->id);
 err_free_binding:
 	kfree(binding);
 err_put_dmabuf:
@@ -302,24 +322,72 @@ err_put_dmabuf:
 	return ERR_PTR(err);
 }
 
-void dev_dmabuf_uninstall(struct net_device *dev)
+struct net_devmem_dmabuf_binding *net_devmem_lookup_dmabuf(u32 id)
 {
 	struct net_devmem_dmabuf_binding *binding;
-	struct netdev_rx_queue *rxq;
-	unsigned long xa_idx;
-	unsigned int i;
 
-	for (i = 0; i < dev->real_num_rx_queues; i++) {
-		binding = dev->_rx[i].mp_params.mp_priv;
-		if (!binding)
-			continue;
+	rcu_read_lock();
+	binding = xa_load(&net_devmem_dmabuf_bindings, id);
+	if (binding) {
+		if (!net_devmem_dmabuf_binding_get(binding))
+			binding = NULL;
+	}
+	rcu_read_unlock();
 
-		xa_for_each(&binding->bound_rxqs, xa_idx, rxq)
-			if (rxq == &dev->_rx[i]) {
-				xa_erase(&binding->bound_rxqs, xa_idx);
-				break;
-			}
+	return binding;
+}
+
+void net_devmem_get_net_iov(struct net_iov *niov)
+{
+	net_devmem_dmabuf_binding_get(net_devmem_iov_binding(niov));
+}
+
+void net_devmem_put_net_iov(struct net_iov *niov)
+{
+	net_devmem_dmabuf_binding_put(net_devmem_iov_binding(niov));
+}
+
+struct net_devmem_dmabuf_binding *net_devmem_get_binding(struct sock *sk,
+							 unsigned int dmabuf_id)
+{
+	struct net_devmem_dmabuf_binding *binding;
+	struct dst_entry *dst = __sk_dst_get(sk);
+	int err = 0;
+
+	binding = net_devmem_lookup_dmabuf(dmabuf_id);
+	if (!binding || !binding->tx_vec) {
+		err = -EINVAL;
+		goto out_err;
+	}
+
+	/* The dma-addrs in this binding are only reachable to the corresponding
+	 * net_device.
+	 */
+	if (!dst || !dst->dev || dst->dev->ifindex != binding->dev->ifindex) {
+		err = -ENODEV;
+		goto out_err;
 	}
+
+	return binding;
+
+out_err:
+	if (binding)
+		net_devmem_dmabuf_binding_put(binding);
+
+	return ERR_PTR(err);
+}
+
+struct net_iov *
+net_devmem_get_niov_at(struct net_devmem_dmabuf_binding *binding,
+		       size_t virt_addr, size_t *off, size_t *size)
+{
+	if (virt_addr >= binding->dmabuf->size)
+		return NULL;
+
+	*off = virt_addr % PAGE_SIZE;
+	*size = PAGE_SIZE - *off;
+
+	return binding->tx_vec[virt_addr / PAGE_SIZE];
 }
 
 /*** "Dmabuf devmem memory provider" ***/
@@ -331,11 +399,11 @@ int mp_dmabuf_devmem_init(struct page_pool *pool)
 	if (!binding)
 		return -EINVAL;
 
-	if (!pool->dma_map)
-		return -EOPNOTSUPP;
-
-	if (pool->dma_sync)
-		return -EOPNOTSUPP;
+	/* dma-buf dma addresses do not need and should not be used with
+	 * dma_sync_for_cpu/device. Force disable dma_sync.
+	 */
+	pool->dma_sync = false;
+	pool->dma_sync_for_cpu = false;
 
 	if (pool->p.order != 0)
 		return -E2BIG;
@@ -387,3 +455,41 @@ bool mp_dmabuf_devmem_release_page(struct page_pool *pool, netmem_ref netmem)
 	/* We don't want the page pool put_page()ing our net_iovs. */
 	return false;
 }
+
+static int mp_dmabuf_devmem_nl_fill(void *mp_priv, struct sk_buff *rsp,
+				    struct netdev_rx_queue *rxq)
+{
+	const struct net_devmem_dmabuf_binding *binding = mp_priv;
+	int type = rxq ? NETDEV_A_QUEUE_DMABUF : NETDEV_A_PAGE_POOL_DMABUF;
+
+	return nla_put_u32(rsp, type, binding->id);
+}
+
+static void mp_dmabuf_devmem_uninstall(void *mp_priv,
+				       struct netdev_rx_queue *rxq)
+{
+	struct net_devmem_dmabuf_binding *binding = mp_priv;
+	struct netdev_rx_queue *bound_rxq;
+	unsigned long xa_idx;
+
+	xa_for_each(&binding->bound_rxqs, xa_idx, bound_rxq) {
+		if (bound_rxq == rxq) {
+			xa_erase(&binding->bound_rxqs, xa_idx);
+			if (xa_empty(&binding->bound_rxqs)) {
+				mutex_lock(&binding->lock);
+				binding->dev = NULL;
+				mutex_unlock(&binding->lock);
+			}
+			break;
+		}
+	}
+}
+
+static const struct memory_provider_ops dmabuf_devmem_ops = {
+	.init			= mp_dmabuf_devmem_init,
+	.destroy		= mp_dmabuf_devmem_destroy,
+	.alloc_netmems		= mp_dmabuf_devmem_alloc_netmems,
+	.release_netmem		= mp_dmabuf_devmem_release_page,
+	.nl_fill		= mp_dmabuf_devmem_nl_fill,
+	.uninstall		= mp_dmabuf_devmem_uninstall,
+};