On Fri, Jun 28, 2024 at 9:43 AM Mina Almasry <almasrymina@xxxxxxxxxx> wrote: > Hi Mina, > Add a netdev_dmabuf_binding struct which represents the > dma-buf-to-netdevice binding. The netlink API will bind the dma-buf to > rx queues on the netdevice. On the binding, the dma_buf_attach > & dma_buf_map_attachment will occur. The entries in the sg_table from > mapping will be inserted into a genpool to make it ready > for allocation. > > The chunks in the genpool are owned by a dmabuf_chunk_owner struct which > holds the dma-buf offset of the base of the chunk and the dma_addr of > the chunk. Both are needed to use allocations that come from this chunk. > > We create a new type that represents an allocation from the genpool: > net_iov. We setup the net_iov allocation size in the > genpool to PAGE_SIZE for simplicity: to match the PAGE_SIZE normally > allocated by the page pool and given to the drivers. > > The user can unbind the dmabuf from the netdevice by closing the netlink > socket that established the binding. We do this so that the binding is > automatically unbound even if the userspace process crashes. > > The binding and unbinding leaves an indicator in struct netdev_rx_queue > that the given queue is bound, but the binding doesn't take effect until > the driver actually reconfigures its queues, and re-initializes its page > pool. > > The netdev_dmabuf_binding struct is refcounted, and releases its > resources only when all the refs are released. > > Signed-off-by: Willem de Bruijn <willemb@xxxxxxxxxx> > Signed-off-by: Kaiyuan Zhang <kaiyuanz@xxxxxxxxxx> > Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx> > Reviewed-by: Pavel Begunkov <asml.silence@xxxxxxxxx> # excluding netlink > > --- > > v13: > - Fixed a couple of places that still listed DMA_BIDIRECTIONAL (Pavel). > - Added reviewed-by from Pavel. > > v11: > - Fix build error with CONFIG_DMA_SHARED_BUFFER && > !CONFIG_GENERIC_ALLOCATOR > - Rebased on top of no memory provider ops. > > v10: > - Moved net_iov_dma_addr() to devmem.h and made it devmem specific > helper (David). > > v9: https://lore.kernel.org/all/20240403002053.2376017-5-almasrymina@xxxxxxxxxx/ > - Removed net_devmem_restart_rx_queues and put it in its own patch > (David). > > v8: > - move dmabuf_devmem_ops usage to later patch to avoid patch-by-patch > build error. > > v7: > - Use IS_ERR() instead of IS_ERR_OR_NULL() for the dma_buf_get() return > value. > - Changes netdev_* naming in devmem.c to net_devmem_* (Yunsheng). > - DMA_BIDIRECTIONAL -> DMA_FROM_DEVICE (Yunsheng). > - Added a comment around recovering of the old rx queue in > net_devmem_restart_rx_queue(), and added freeing of old_mem if the > restart of the old queue fails. (Yunsheng). > - Use kernel-family sock-priv (Jakub). > - Put pp_memory_provider_params in netdev_rx_queue instead of the > dma-buf specific binding (Pavel & David). > - Move queue management ops to queue_mgmt_ops instead of netdev_ops > (Jakub). > - Remove excess whitespaces (Jakub). > - Use genlmsg_iput (Jakub). > > v6: > - Validate rx queue index > - Refactor new functions into devmem.c (Pavel) > > v5: > - Renamed page_pool_iov to net_iov, and moved that support to devmem.h > or netmem.h. > > v1: > - Introduce devmem.h instead of bloating netdevice.h (Jakub) > - ENOTSUPP -> EOPNOTSUPP (checkpatch.pl I think) > - Remove unneeded rcu protection for binding->list (rtnl protected) > - Removed extraneous err_binding_put: label. > - Removed dma_addr += len (Paolo). > - Don't override err on netdev_bind_dmabuf_to_queue failure. > - Rename devmem -> dmabuf (David). > - Add id to dmabuf binding (David/Stan). > - Fix missing xa_destroy bound_rq_list. > - Use queue api to reset bound RX queues (Jakub). > - Update netlink API for rx-queue type (tx/re) (Jakub). > > RFC v3: > - Support multi rx-queue binding > > --- > Documentation/netlink/specs/netdev.yaml | 4 + > include/net/devmem.h | 111 +++++++++++ > include/net/netdev_rx_queue.h | 2 + > include/net/netmem.h | 10 + > include/net/page_pool/types.h | 6 + > net/core/Makefile | 2 +- > net/core/dev.c | 3 + > net/core/devmem.c | 252 ++++++++++++++++++++++++ > net/core/netdev-genl-gen.c | 4 + > net/core/netdev-genl-gen.h | 4 + > net/core/netdev-genl.c | 101 +++++++++- > 11 files changed, 496 insertions(+), 3 deletions(-) > create mode 100644 include/net/devmem.h > create mode 100644 net/core/devmem.c > > diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml > index 899ac0882a098..d6d7cb01c145c 100644 > --- a/Documentation/netlink/specs/netdev.yaml > +++ b/Documentation/netlink/specs/netdev.yaml > @@ -673,6 +673,10 @@ operations: > - tx-packets > - tx-bytes > > +kernel-family: > + headers: [ "linux/list.h"] > + sock-priv: struct list_head > + > mcast-groups: > list: > - > diff --git a/include/net/devmem.h b/include/net/devmem.h > new file mode 100644 > index 0000000000000..eaf3fd965d7a8 > --- /dev/null > +++ b/include/net/devmem.h > @@ -0,0 +1,111 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > +/* > + * Device memory TCP support > + * > + * Authors: Mina Almasry <almasrymina@xxxxxxxxxx> > + * Willem de Bruijn <willemb@xxxxxxxxxx> > + * Kaiyuan Zhang <kaiyuanz@xxxxxxxxxx> > + * > + */ > +#ifndef _NET_DEVMEM_H > +#define _NET_DEVMEM_H > + > +struct net_devmem_dmabuf_binding { > + struct dma_buf *dmabuf; > + struct dma_buf_attachment *attachment; > + struct sg_table *sgt; > + struct net_device *dev; > + struct gen_pool *chunk_pool; > + > + /* The user holds a ref (via the netlink API) for as long as they want > + * the binding to remain alive. Each page pool using this binding holds > + * a ref to keep the binding alive. Each allocated net_iov holds a > + * ref. > + * > + * The binding undos itself and unmaps the underlying dmabuf once all > + * those refs are dropped and the binding is no longer desired or in > + * use. > + */ > + refcount_t ref; > + > + /* The list of bindings currently active. Used for netlink to notify us > + * of the user dropping the bind. > + */ > + struct list_head list; > + > + /* rxq's this binding is active on. */ > + struct xarray bound_rxq_list; > + > + /* ID of this binding. Globally unique to all bindings currently > + * active. > + */ > + u32 id; > +}; > + > +/* Owner of the dma-buf chunks inserted into the gen pool. Each scatterlist > + * entry from the dmabuf is inserted into the genpool as a chunk, and needs > + * this owner struct to keep track of some metadata necessary to create > + * allocations from this chunk. > + */ > +struct dmabuf_genpool_chunk_owner { > + /* Offset into the dma-buf where this chunk starts. */ > + unsigned long base_virtual; > + > + /* dma_addr of the start of the chunk. */ > + dma_addr_t base_dma_addr; > + > + /* Array of net_iovs for this chunk. */ > + struct net_iov *niovs; > + size_t num_niovs; > + > + struct net_devmem_dmabuf_binding *binding; > +}; > + > +#if defined(CONFIG_DMA_SHARED_BUFFER) && defined(CONFIG_GENERIC_ALLOCATOR) > +void __net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding); > +int net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, > + struct net_devmem_dmabuf_binding **out); > +void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding); > +int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx, > + struct net_devmem_dmabuf_binding *binding); > +#else > +static inline void > +__net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding) > +{ > +} > + > +static inline int net_devmem_bind_dmabuf(struct net_device *dev, > + unsigned int dmabuf_fd, > + struct net_devmem_dmabuf_binding **out) > +{ > + return -EOPNOTSUPP; > +} > +static inline void > +net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding) > +{ > +} > + > +static inline int > +net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx, > + struct net_devmem_dmabuf_binding *binding) > +{ > + return -EOPNOTSUPP; > +} > +#endif > + > +static inline void > +net_devmem_dmabuf_binding_get(struct net_devmem_dmabuf_binding *binding) > +{ > + refcount_inc(&binding->ref); > +} > + > +static inline void > +net_devmem_dmabuf_binding_put(struct net_devmem_dmabuf_binding *binding) > +{ > + if (!refcount_dec_and_test(&binding->ref)) > + return; > + > + __net_devmem_dmabuf_binding_free(binding); > +} > + > +#endif /* _NET_DEVMEM_H */ > diff --git a/include/net/netdev_rx_queue.h b/include/net/netdev_rx_queue.h > index e78ca52d67fbf..ac34f5fb4f71d 100644 > --- a/include/net/netdev_rx_queue.h > +++ b/include/net/netdev_rx_queue.h > @@ -6,6 +6,7 @@ > #include <linux/netdevice.h> > #include <linux/sysfs.h> > #include <net/xdp.h> > +#include <net/page_pool/types.h> > > /* This structure contains an instance of an RX queue. */ > struct netdev_rx_queue { > @@ -25,6 +26,7 @@ struct netdev_rx_queue { > * Readers and writers must hold RTNL > */ > struct napi_struct *napi; > + struct pp_memory_provider_params mp_params; > } ____cacheline_aligned_in_smp; > > /* > diff --git a/include/net/netmem.h b/include/net/netmem.h > index d8b810245c1da..72e932a1a9489 100644 > --- a/include/net/netmem.h > +++ b/include/net/netmem.h > @@ -8,6 +8,16 @@ > #ifndef _NET_NETMEM_H > #define _NET_NETMEM_H > > +#include <net/devmem.h> > + > +/* net_iov */ > + > +struct net_iov { > + struct dmabuf_genpool_chunk_owner *owner; > +}; > + > +/* netmem */ > + > /** > * typedef netmem_ref - a nonexistent type marking a reference to generic > * network memory. > diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h > index 7e8477057f3d1..9f3c3ee2ee755 100644 > --- a/include/net/page_pool/types.h > +++ b/include/net/page_pool/types.h > @@ -128,6 +128,10 @@ struct page_pool_stats { > }; > #endif > > +struct pp_memory_provider_params { > + void *mp_priv; > +}; > + > struct page_pool { > struct page_pool_params_fast p; > > @@ -194,6 +198,8 @@ struct page_pool { > */ > struct ptr_ring ring; > > + void *mp_priv; > + > #ifdef CONFIG_PAGE_POOL_STATS > /* recycle stats are per-cpu to avoid locking */ > struct page_pool_recycle_stats __percpu *recycle_stats; > diff --git a/net/core/Makefile b/net/core/Makefile > index f82232b358a2c..6b43611fb4a43 100644 > --- a/net/core/Makefile > +++ b/net/core/Makefile > @@ -13,7 +13,7 @@ obj-y += dev.o dev_addr_lists.o dst.o netevent.o \ > neighbour.o rtnetlink.o utils.o link_watch.o filter.o \ > sock_diag.o dev_ioctl.o tso.o sock_reuseport.o \ > fib_notifier.o xdp.o flow_offload.o gro.o \ > - netdev-genl.o netdev-genl-gen.o gso.o > + netdev-genl.o netdev-genl-gen.o gso.o devmem.o > > obj-$(CONFIG_NETDEV_ADDR_LIST_TEST) += dev_addr_lists_test.o > > diff --git a/net/core/dev.c b/net/core/dev.c > index 0a23d7da7fbc6..5e5e2d266b83f 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -158,6 +158,9 @@ > #include <net/page_pool/types.h> > #include <net/page_pool/helpers.h> > #include <net/rps.h> > +#include <linux/genalloc.h> > +#include <linux/dma-buf.h> > +#include <net/devmem.h> > > #include "dev.h" > #include "net-sysfs.h" > diff --git a/net/core/devmem.c b/net/core/devmem.c > new file mode 100644 > index 0000000000000..cfb5a2f69dcd2 > --- /dev/null > +++ b/net/core/devmem.c > @@ -0,0 +1,252 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Devmem TCP > + * > + * Authors: Mina Almasry <almasrymina@xxxxxxxxxx> > + * Willem de Bruijn <willemdebruijn.kernel@xxxxxxxxx> > + * Kaiyuan Zhang <kaiyuanz@xxxxxxxxxx > + */ > + > +#include <linux/types.h> > +#include <linux/mm.h> > +#include <linux/netdevice.h> > +#include <trace/events/page_pool.h> > +#include <net/netdev_rx_queue.h> > +#include <net/page_pool/types.h> > +#include <net/page_pool/helpers.h> > +#include <linux/genalloc.h> > +#include <linux/dma-buf.h> > +#include <net/devmem.h> > +#include <net/netdev_queues.h> > + > +/* Device memory support */ > + > +#if defined(CONFIG_DMA_SHARED_BUFFER) && defined(CONFIG_GENERIC_ALLOCATOR) > +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); > + kfree(owner); > +} > + > +void __net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding) > +{ > + size_t size, avail; > + > + gen_pool_for_each_chunk(binding->chunk_pool, > + net_devmem_dmabuf_free_chunk_owner, NULL); > + > + size = gen_pool_size(binding->chunk_pool); > + avail = gen_pool_avail(binding->chunk_pool); > + > + if (!WARN(size != avail, "can't destroy genpool. size=%zu, avail=%zu", > + size, avail)) > + gen_pool_destroy(binding->chunk_pool); > + > + dma_buf_unmap_attachment(binding->attachment, binding->sgt, > + DMA_FROM_DEVICE); > + dma_buf_detach(binding->dmabuf, binding->attachment); > + dma_buf_put(binding->dmabuf); > + xa_destroy(&binding->bound_rxq_list); > + kfree(binding); > +} > + > +/* Protected by rtnl_lock() */ > +static DEFINE_XARRAY_FLAGS(net_devmem_dmabuf_bindings, XA_FLAGS_ALLOC1); > + > +void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding) > +{ > + struct netdev_rx_queue *rxq; > + unsigned long xa_idx; > + unsigned int rxq_idx; > + > + if (!binding) > + return; > + > + if (binding->list.next) > + list_del(&binding->list); > + > + xa_for_each(&binding->bound_rxq_list, xa_idx, rxq) { > + if (rxq->mp_params.mp_priv == binding) { > + /* We hold the rtnl_lock while binding/unbinding > + * dma-buf, so we can't race with another thread that > + * is also modifying this value. However, the page_pool > + * may read this config while it's creating its > + * rx-queues. WRITE_ONCE() here to match the > + * READ_ONCE() in the page_pool. > + */ > + WRITE_ONCE(rxq->mp_params.mp_priv, NULL); > + > + rxq_idx = get_netdev_rx_queue_index(rxq); > + > + netdev_rx_queue_restart(binding->dev, rxq_idx); > + } > + } > + > + xa_erase(&net_devmem_dmabuf_bindings, binding->id); > + > + net_devmem_dmabuf_binding_put(binding); > +} > + > +int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx, > + struct net_devmem_dmabuf_binding *binding) > +{ > + struct netdev_rx_queue *rxq; > + u32 xa_idx; > + int err; > + > + if (rxq_idx >= dev->num_rx_queues) > + return -ERANGE; > + > + rxq = __netif_get_rx_queue(dev, rxq_idx); > + if (rxq->mp_params.mp_priv) > + return -EEXIST; > + > + err = xa_alloc(&binding->bound_rxq_list, &xa_idx, rxq, xa_limit_32b, > + GFP_KERNEL); > + if (err) > + return err; > + > + /* We hold the rtnl_lock while binding/unbinding dma-buf, so we can't > + * race with another thread that is also modifying this value. However, > + * the driver may read this config while it's creating its * rx-queues. > + * WRITE_ONCE() here to match the READ_ONCE() in the driver. > + */ > + WRITE_ONCE(rxq->mp_params.mp_priv, binding); > + > + err = netdev_rx_queue_restart(dev, rxq_idx); > + if (err) > + goto err_xa_erase; > + > + return 0; > + > +err_xa_erase: > + WRITE_ONCE(rxq->mp_params.mp_priv, NULL); > + xa_erase(&binding->bound_rxq_list, xa_idx); > + > + return err; > +} > + > +int net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, > + struct net_devmem_dmabuf_binding **out) > +{ > + struct net_devmem_dmabuf_binding *binding; > + static u32 id_alloc_next; > + struct scatterlist *sg; > + struct dma_buf *dmabuf; > + unsigned int sg_idx, i; > + unsigned long virtual; > + int err; > + > + dmabuf = dma_buf_get(dmabuf_fd); > + if (IS_ERR(dmabuf)) > + return -EBADFD; > + > + binding = kzalloc_node(sizeof(*binding), GFP_KERNEL, > + dev_to_node(&dev->dev)); > + if (!binding) { > + err = -ENOMEM; > + goto err_put_dmabuf; > + } > + > + 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_rxq_list, XA_FLAGS_ALLOC); > + > + refcount_set(&binding->ref, 1); > + > + binding->dmabuf = dmabuf; > + > + binding->attachment = dma_buf_attach(binding->dmabuf, dev->dev.parent); > + if (IS_ERR(binding->attachment)) { > + err = PTR_ERR(binding->attachment); > + goto err_free_id; > + } > + > + binding->sgt = > + dma_buf_map_attachment(binding->attachment, DMA_FROM_DEVICE); > + if (IS_ERR(binding->sgt)) { > + err = PTR_ERR(binding->sgt); > + goto err_detach; > + } > + > + /* 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)); > + if (!binding->chunk_pool) { > + err = -ENOMEM; > + goto err_unmap; > + } > + > + virtual = 0; > + for_each_sgtable_dma_sg(binding->sgt, sg, sg_idx) { > + dma_addr_t dma_addr = sg_dma_address(sg); > + struct dmabuf_genpool_chunk_owner *owner; > + size_t len = sg_dma_len(sg); > + struct net_iov *niov; > + > + owner = kzalloc_node(sizeof(*owner), GFP_KERNEL, > + dev_to_node(&dev->dev)); > + owner->base_virtual = virtual; > + owner->base_dma_addr = dma_addr; > + owner->num_niovs = len / PAGE_SIZE; > + owner->binding = binding; > + > + err = gen_pool_add_owner(binding->chunk_pool, dma_addr, > + dma_addr, len, dev_to_node(&dev->dev), > + owner); > + if (err) { > + err = -EINVAL; > + goto err_free_chunks; > + } > + > + owner->niovs = kvmalloc_array(owner->num_niovs, > + sizeof(*owner->niovs), > + GFP_KERNEL); > + if (!owner->niovs) { > + err = -ENOMEM; > + goto err_free_chunks; > + } > + > + for (i = 0; i < owner->num_niovs; i++) { > + niov = &owner->niovs[i]; > + niov->owner = owner; > + } > + > + virtual += len; > + } > + > + *out = binding; > + > + return 0; > + > +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_unmap: > + dma_buf_unmap_attachment(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: > + dma_buf_put(dmabuf); > + return err; > +} > +#endif > diff --git a/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c > index 9acd0d893765a..3dcd25049e593 100644 > --- a/net/core/netdev-genl-gen.c > +++ b/net/core/netdev-genl-gen.c > @@ -9,6 +9,7 @@ > #include "netdev-genl-gen.h" > > #include <uapi/linux/netdev.h> > +#include <linux/list.h> > > /* Integer value ranges */ > static const struct netlink_range_validation netdev_a_page_pool_id_range = { > @@ -187,4 +188,7 @@ struct genl_family netdev_nl_family __ro_after_init = { > .n_split_ops = ARRAY_SIZE(netdev_nl_ops), > .mcgrps = netdev_nl_mcgrps, > .n_mcgrps = ARRAY_SIZE(netdev_nl_mcgrps), > + .sock_priv_size = sizeof(struct list_head), > + .sock_priv_init = (void *)netdev_nl_sock_priv_init, > + .sock_priv_destroy = (void *)netdev_nl_sock_priv_destroy, > }; > diff --git a/net/core/netdev-genl-gen.h b/net/core/netdev-genl-gen.h > index ca5a0983f2834..2c431b7dcbc84 100644 > --- a/net/core/netdev-genl-gen.h > +++ b/net/core/netdev-genl-gen.h > @@ -10,6 +10,7 @@ > #include <net/genetlink.h> > > #include <uapi/linux/netdev.h> > +#include <linux/list.h> > > /* Common nested types */ > extern const struct nla_policy netdev_page_pool_info_nl_policy[NETDEV_A_PAGE_POOL_IFINDEX + 1]; > @@ -40,4 +41,7 @@ enum { > > extern struct genl_family netdev_nl_family; > > +void netdev_nl_sock_priv_init(struct list_head *priv); > +void netdev_nl_sock_priv_destroy(struct list_head *priv); > + > #endif /* _LINUX_NETDEV_GEN_H */ > diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c > index 2d726e65211dd..133884eb13349 100644 > --- a/net/core/netdev-genl.c > +++ b/net/core/netdev-genl.c > @@ -10,6 +10,7 @@ > #include <net/netdev_rx_queue.h> > #include <net/netdev_queues.h> > #include <net/busy_poll.h> > +#include <net/devmem.h> > > #include "netdev-genl-gen.h" > #include "dev.h" > @@ -721,10 +722,92 @@ int netdev_nl_qstats_get_dumpit(struct sk_buff *skb, > return err; > } > > -/* Stub */ > int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info) > { > - return 0; > + struct nlattr *tb[ARRAY_SIZE(netdev_queue_dmabuf_nl_policy)]; > + struct net_devmem_dmabuf_binding *out_binding; > + struct list_head *sock_binding_list; > + u32 ifindex, dmabuf_fd, rxq_idx; > + struct net_device *netdev; > + struct sk_buff *rsp; > + struct nlattr *attr; > + int rem, err = 0; > + void *hdr; > + > + if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_DEV_IFINDEX) || > + GENL_REQ_ATTR_CHECK(info, NETDEV_A_BIND_DMABUF_DMABUF_FD) || > + GENL_REQ_ATTR_CHECK(info, NETDEV_A_BIND_DMABUF_QUEUES)) > + return -EINVAL; > + > + ifindex = nla_get_u32(info->attrs[NETDEV_A_DEV_IFINDEX]); > + dmabuf_fd = nla_get_u32(info->attrs[NETDEV_A_BIND_DMABUF_DMABUF_FD]); > + > + rtnl_lock(); > + > + netdev = __dev_get_by_index(genl_info_net(info), ifindex); > + if (!netdev) { > + err = -ENODEV; > + goto err_unlock; > + } > + > + err = net_devmem_bind_dmabuf(netdev, dmabuf_fd, &out_binding); > + if (err) > + goto err_unlock; > + > + nla_for_each_attr(attr, genlmsg_data(info->genlhdr), > + genlmsg_len(info->genlhdr), rem) { > + if (nla_type(attr) != NETDEV_A_BIND_DMABUF_QUEUES) > + continue; > + > + err = nla_parse_nested( > + tb, ARRAY_SIZE(netdev_queue_dmabuf_nl_policy) - 1, attr, > + netdev_queue_dmabuf_nl_policy, info->extack); > + if (err < 0) > + goto err_unbind; > + > + rxq_idx = nla_get_u32(tb[NETDEV_A_QUEUE_DMABUF_IDX]); > + > + err = net_devmem_bind_dmabuf_to_queue(netdev, rxq_idx, > + out_binding); > + if (err) > + goto err_unbind; > + } > + > + sock_binding_list = genl_sk_priv_get(&netdev_nl_family, > + NETLINK_CB(skb).sk); > + if (IS_ERR(sock_binding_list)) { > + err = PTR_ERR(sock_binding_list); > + goto err_unbind; > + } > + > + list_add(&out_binding->list, sock_binding_list); > + > + rsp = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); > + if (!rsp) { > + err = -ENOMEM; > + goto err_unbind; > + } > + > + hdr = genlmsg_iput(rsp, info); > + if (!hdr) { > + err = -EMSGSIZE; > + goto err_genlmsg_free; > + } > + > + nla_put_u32(rsp, NETDEV_A_BIND_DMABUF_DMABUF_ID, out_binding->id); > + genlmsg_end(rsp, hdr); > + > + rtnl_unlock(); > + > + return genlmsg_reply(rsp, info); > + > +err_genlmsg_free: > + nlmsg_free(rsp); > +err_unbind: > + net_devmem_unbind_dmabuf(out_binding); > +err_unlock: > + rtnl_unlock(); > + return err; > } > > static int netdev_genl_netdevice_event(struct notifier_block *nb, > @@ -771,3 +854,17 @@ static int __init netdev_genl_init(void) > } > > subsys_initcall(netdev_genl_init); > + > +void netdev_nl_sock_priv_init(struct list_head *priv) > +{ > + INIT_LIST_HEAD(priv); > +} > + > +void netdev_nl_sock_priv_destroy(struct list_head *priv) > +{ > + struct net_devmem_dmabuf_binding *binding; > + struct net_devmem_dmabuf_binding *temp; > + > + list_for_each_entry_safe(binding, temp, priv, list) > + net_devmem_unbind_dmabuf(binding); > +} > -- > 2.45.2.803.g4e1b14247a-goog > > I found several locking warnings while testing. [ 1135.125874] WARNING: CPU: 1 PID: 1644 at drivers/dma-buf/dma-buf.c:1123 dma_buf_map_attachment+0x164/0x2f0 [ 1135.136255] Modules linked in: 8021q garp mrp xt_nat xt_tcpudp veth xt_conntrack nft_chain_nat xt_MASQUERADE nf_nat nf _conntrack_netlink nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xfrm_user xt_addrtype nft_compat nf_tables br_netfilter bri dge stp llc qrtr crct10dif_pclmul overlay crc32_generic crc32_pclmul crc32c_intel ghash_clmulni_intel sha512_ssse3 sha256 _ssse3 sha1_ssse3 xts amdgpu cts wmi_bmof aesni_intel amdxcp i2c_algo_bit crypto_simd drm_ttm_helper cryptd ttm drm_exec bnxt_en ionic gpu_sched drm_suballoc_helper drm_buddy ptp video drm_display_helper drm_kms_helper wmi cfg80211 drm drm_pa nel_orientation_quirks backlight nfnetlink bpf_preload ip_tables x_tables [ 1135.196164] CPU: 1 PID: 1644 Comm: ncdevmem Not tainted 6.10.0-rc5+ #43 6e089cf25edb5a71cabb8ab97c9dfbf7e96b1a3a [ 1135.207060] Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 0603 11/01/2021 [ 1135.215959] RIP: 0010:dma_buf_map_attachment+0x164/0x2f0 [ 1135.221996] Code: ea 03 80 3c 02 00 0f 85 4e 01 00 00 49 8b bc 24 b8 00 00 00 be ff ff ff ff 48 83 c7 70 e8 54 e6 e2 0 0 85 c0 0f 85 32 ff ff ff <0f> 0b e9 2b ff ff ff 89 ee 48 89 df e8 6b f1 ff ff 48 85 c0 0f 84 [ 1135.241464] RSP: 0018:ffff888224c2f5d0 EFLAGS: 00010246 [ 1135.247409] RAX: 0000000000000000 RBX: ffff88821dcc65f0 RCX: 0000000000000001 [ 1135.255259] RDX: 0000000000000001 RSI: ffffffff86abed00 RDI: ffffffff86d56be0 [ 1135.263109] RBP: 0000000000000002 R08: 0000000000000001 R09: ffffed1044985ea0 [ 1135.270960] R10: 0000000000000001 R11: 0000000000000000 R12: ffff88812da88400 [ 1135.278808] R13: ffff88821dcc65f0 R14: ffff888224c2f838 R15: 0000000000000005 [ 1135.286650] FS: 00007fe9b77b4740(0000) GS:ffff88881b200000(0000) knlGS:0000000000000000 [ 1135.295447] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1135.301912] CR2: 0000556a6a61f870 CR3: 00000001094a0000 CR4: 00000000007506f0 [ 1135.309893] PKRU: 55555554 [ 1135.313321] Call Trace: [ 1135.316486] <TASK> [ 1135.319307] ? __warn+0xc8/0x2f0 [ 1135.323290] ? dma_buf_map_attachment+0x164/0x2f0 [ 1135.328907] ? report_bug+0x326/0x3c0 [ 1135.333368] ? handle_bug+0x3c/0x70 [ 1135.337568] ? exc_invalid_op+0x14/0x50 [ 1135.342202] ? asm_exc_invalid_op+0x16/0x20 [ 1135.347134] ? dma_buf_map_attachment+0x164/0x2f0 [ 1135.352686] net_devmem_bind_dmabuf+0x2af/0xab0 [ 1135.357940] ? __nla_validate_parse+0x109e/0x2830 [ 1135.363430] netdev_nl_bind_rx_doit+0x26f/0xe00 [ 1135.368675] ? __pfx___nla_validate_parse+0x10/0x10 [ 1135.374333] ? __pfx_netdev_nl_bind_rx_doit+0x10/0x10 [ 1135.380094] ? trace_kmalloc+0x2d/0xd0 [ 1135.384637] ? __kmalloc_noprof+0x1f5/0x430 [ 1135.389539] ? __pfx_mark_lock.part.0+0x10/0x10 [ 1135.394851] ? __nla_parse+0x22/0x30 [ 1135.399139] ? genl_family_rcv_msg_attrs_parse.constprop.0+0x162/0x240 [ 1135.406403] genl_family_rcv_msg_doit+0x1d4/0x2b0 [ 1135.411872] ? __pfx_genl_family_rcv_msg_doit+0x10/0x10 [ 1135.417892] genl_rcv_msg+0x3fb/0x6c0 [ 1136.178258] WARNING: CPU: 1 PID: 1644 at drivers/dma-buf/dma-buf.c:1226 dma_buf_unmap_attachment+0x267/0x320 [ 1136.188842] Modules linked in: 8021q garp mrp xt_nat xt_tcpudp veth xt_conntrack nft_chain_nat xt_MASQUERADE nf_nat nf _conntrack_netlink nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xfrm_user xt_addrtype nft_compat nf_tables br_netfilter bri dge stp llc qrtr crct10dif_pclmul overlay crc32_generic crc32_pclmul crc32c_intel ghash_clmulni_intel sha512_ssse3 sha256 _ssse3 sha1_ssse3 xts amdgpu cts wmi_bmof aesni_intel amdxcp i2c_algo_bit crypto_simd drm_ttm_helper cryptd ttm drm_exec bnxt_en ionic gpu_sched drm_suballoc_helper drm_buddy ptp video drm_display_helper drm_kms_helper wmi cfg80211 drm drm_pa nel_orientation_quirks backlight nfnetlink bpf_preload ip_tables x_tables [ 1136.248891] CPU: 1 PID: 1644 Comm: ncdevmem Tainted: G W 6.10.0-rc5+ #43 6e089cf25edb5a71cabb8ab97c9dfbf7e96b1a3a [ 1136.261273] Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 0603 11/01/2021 [ 1136.270266] RIP: 0010:dma_buf_unmap_attachment+0x267/0x320 [ 1136.276468] Code: c1 ea 03 80 3c 02 00 0f 85 c1 00 00 00 48 8b bb b8 00 00 00 be ff ff ff ff 48 83 c7 70 e8 11 e1 e2 0 0 85 c0 0f 85 42 fe ff ff <0f> 0b e9 3b fe ff ff 48 89 cf 4c 89 44 24 10 e8 35 c8 21 ff 4c 8b [ 1136.295967] RSP: 0018:ffff888224c2fb78 EFLAGS: 00010246 [ 1136.301930] RAX: 0000000000000000 RBX: ffff88812da88400 RCX: 0000000000000001 [ 1136.309804] RDX: 0000000000000001 RSI: ffffffff86abed00 RDI: ffffffff86d56be0 [ 1136.317810] RBP: ffff88810908e250 R08: 0000000000000001 R09: fffffbfff21514d8 [ 1136.325670] R10: 0000000000000001 R11: 0000000000000000 R12: ffff88821dcc65f0 [ 1136.333608] R13: 0000000000010000 R14: ffffed102265e337 R15: 1ffff11044985f81 [ 1136.341462] FS: 00007fe9b77b4740(0000) GS:ffff88881b200000(0000) knlGS:0000000000000000 [ 1136.350278] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1136.356766] CR2: 000055dec9867ba0 CR3: 00000001094a0000 CR4: 00000000007506f0 [ 1136.364640] PKRU: 55555554 [ 1136.368172] Call Trace: [ 1136.371373] <TASK> [ 1136.374275] ? __warn+0xc8/0x2f0 [ 1136.378230] ? dma_buf_unmap_attachment+0x267/0x320 [ 1136.383855] ? report_bug+0x326/0x3c0 [ 1136.388324] ? handle_bug+0x3c/0x70 [ 1136.392549] ? exc_invalid_op+0x14/0x50 [ 1136.397126] ? asm_exc_invalid_op+0x16/0x20 [ 1136.402126] ? dma_buf_unmap_attachment+0x267/0x320 [ 1136.407727] ? dma_buf_unmap_attachment+0x25f/0x320 [ 1136.413344] __net_devmem_dmabuf_binding_free+0x10a/0x220 [ 1136.419728] net_devmem_unbind_dmabuf+0x349/0x440 [ 1136.425146] ? __pfx_lock_release+0x10/0x10 [ 1136.430080] ? __pfx_net_devmem_unbind_dmabuf+0x10/0x10 [ 1136.436106] netdev_nl_sock_priv_destroy+0x72/0xc0 [ 1136.441611] genl_release+0xed/0x190 [ 1136.445921] ? __pfx_genl_release+0x10/0x10 [ 1136.450823] ? mark_held_locks+0xa5/0xf0 [ 1136.455490] ? __local_bh_enable_ip+0xa5/0x120 [ 1136.460790] ? __pfx_genl_release+0x10/0x10 [ 1136.465703] netlink_release+0x839/0x18f0 [ 1135.709313] WARNING: CPU: 3 PID: 1644 at net/core/netdev_rx_queue.c:18 netdev_rx_queue_restart+0x3f4/0x5a0 [ 1135.719686] Modules linked in: 8021q garp mrp xt_nat xt_tcpudp veth xt_conntrack nft_chain_nat xt_MASQUERADE nf_nat nf _conntrack_netlink nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xfrm_user xt_addrtype nft_compat nf_tables br_netfilter bri dge stp llc qrtr crct10dif_pclmul overlay crc32_generic crc32_pclmul crc32c_intel ghash_clmulni_intel sha512_ssse3 sha256 _ssse3 sha1_ssse3 xts amdgpu cts wmi_bmof aesni_intel amdxcp i2c_algo_bit crypto_simd drm_ttm_helper cryptd ttm drm_exec bnxt_en ionic gpu_sched drm_suballoc_helper drm_buddy ptp video drm_display_helper drm_kms_helper wmi cfg80211 drm drm_pa nel_orientation_quirks backlight nfnetlink bpf_preload ip_tables x_tables [ 1135.779526] CPU: 3 PID: 1644 Comm: ncdevmem Tainted: G W 6.10.0-rc5+ #43 6e089cf25edb5a71cabb8ab97c9df bf7e96b1a3a [ 1135.791882] Hardware name: ASUS System Product Name/PRIME Z690-P D4, BIOS 0603 11/01/2021 [ 1135.800781] RIP: 0010:netdev_rx_queue_restart+0x3f4/0x5a0 [ 1135.806905] Code: d0 0f 1f 00 48 89 df e8 9a ce a9 fe 4c 89 f7 e8 92 ce a9 fe 48 83 c4 08 44 89 e0 5b 5d 41 5c 41 5d 4 1 5e 41 5f c3 cc cc cc cc <0f> 0b e9 05 fd ff ff 44 89 fe 48 c7 c7 80 70 fc 86 e8 46 7c 38 fe [ 1135.826382] RSP: 0018:ffff888224c2fbb0 EFLAGS: 00010246 [ 1135.832339] RAX: 0000000000000000 RBX: ffffffffc0bb5c80 RCX: ffffffff842d81c3 [ 1135.840185] RDX: 1ffffffff1e6fc44 RSI: 0000000000000008 RDI: ffffffff8f37e220 [ 1135.848028] RBP: ffff88814b864000 R08: 0000000000000000 R09: fffffbfff1e6fc44 [ 1135.855875] R10: ffffffff8f37e227 R11: 0000000000000000 R12: ffff888224c2fc28 [ 1135.863716] R13: ffff88814b864be0 R14: ffffed102265e337 R15: 0000000000000001 [ 1135.871560] FS: 00007fe9b77b4740(0000) GS:ffff88881ba00000(0000) knlGS:0000000000000000 [ 1135.880364] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1135.886824] CR2: 00007f5f22a21f50 CR3: 00000001094a0000 CR4: 00000000007506f0 [ 1135.894670] PKRU: 55555554 [ 1135.898090] Call Trace: [ 1135.901255] <TASK> [ 1135.904073] ? __warn+0xc8/0x2f0 [ 1135.908020] ? netdev_rx_queue_restart+0x3f4/0x5a0 [ 1135.913524] ? report_bug+0x326/0x3c0 [ 1135.917908] ? handle_bug+0x3c/0x70 [ 1135.922112] ? exc_invalid_op+0x14/0x50 [ 1135.926671] ? asm_exc_invalid_op+0x16/0x20 [ 1135.931591] ? mutex_is_locked+0x13/0x50 [ 1135.936238] ? netdev_rx_queue_restart+0x3f4/0x5a0 [ 1135.941748] net_devmem_unbind_dmabuf+0x2a3/0x440 [ 1135.947179] ? __pfx_lock_release+0x10/0x10 [ 1135.952081] ? __pfx_net_devmem_unbind_dmabuf+0x10/0x10 [ 1135.958040] netdev_nl_sock_priv_destroy+0x72/0xc0 [ 1135.963561] genl_release+0xed/0x190 [ 1135.967851] ? __pfx_genl_release+0x10/0x10 [ 1135.972755] ? mark_held_locks+0xa5/0xf0 [ 1135.977392] ? __local_bh_enable_ip+0xa5/0x120 [ 1135.982561] ? __pfx_genl_release+0x10/0x10 [ 1135.987464] netlink_release+0x839/0x18f0 Thanks! Taehee Yoo
