Something went wrong. Try again.
(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
Something went wrong. Try again.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229/* SPDX-License-Identifier: GPL-2.0-or-later *//* * Device memory TCP support * * Authors: Mina Almasry <almasrymina@google.com> * Willem de Bruijn <willemb@google.com> * Kaiyuan Zhang <kaiyuanz@google.com> * */#ifndef _NET_DEVMEM_H#define _NET_DEVMEM_H
#include <net/net_namespace.h>#include <net/netmem.h>#include <net/netdev_netlink.h>
struct netlink_ext_ack;
struct net_devmem_dmabuf_binding { struct net_iov_area area; struct dma_buf *dmabuf; struct dma_buf_attachment *attachment; struct sg_table *sgt; /* Physical NIC that does the actual DMA for this binding. */ struct net_device *dev; /* Opaque cookie identifying the virtual device (e.g. netkit) the user * called bind-tx on. Used only for pointer comparison. Never * dereferenced. */ void *vdev; possible_net_t net; kuid_t uid; /* Protect dev */ struct mutex lock;
/* 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. The page_pool does not release the * ref until all the net_iovs allocated from this binding are released * back to the page_pool. * * 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. * * net_devmem_net_iov_inc_ref() on dmabuf net_iovs will increment this * reference, making sure that the binding remains alive until all the * net_iovs are no longer used. net_iovs allocated from this binding * that are stuck in the TX path for any reason (such as awaiting * retransmits) hold a reference to the binding until the skb holding * them is freed. */ struct percpu_ref 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_rxqs;
spinlock_t freelist_lock ____cacheline_aligned_in_smp; u32 free_count; u32 *freelist;
/* ID of this binding. Globally unique to all bindings currently * active. */ u32 id;
/* DMA direction, FROM_DEVICE for Rx binding, TO_DEVICE for Tx. */ enum dma_data_direction direction;
/* Array of net_iov pointers for this binding, sorted by virtual * address. This array is convenient to map the virtual addresses to * net_iovs in the TX path. */ struct net_iov **tx_vec;
unsigned int niov_shift;
struct work_struct unbind_w;};
#if defined(CONFIG_NET_DEVMEM)void __net_devmem_dmabuf_binding_free(struct work_struct *wq);struct net_devmem_dmabuf_binding *net_devmem_bind_dmabuf(struct net_device *dev, void *vdev, struct device *dma_dev, enum dma_data_direction direction, unsigned int dmabuf_fd, unsigned int niov_shift, struct netdev_nl_sock *priv, const struct sock *nl_sk, struct netlink_ext_ack *extack);struct net_devmem_dmabuf_binding *net_devmem_lookup_dmabuf(u32 id);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, struct netlink_ext_ack *extack);
static inline struct net_devmem_dmabuf_binding *net_devmem_iov_binding(const struct net_iov *niov){ return container_of(net_iov_owner(niov), struct net_devmem_dmabuf_binding, area);}
static inline u32 net_devmem_iov_binding_id(const struct net_iov *niov){ return net_devmem_iov_binding(niov)->id;}
static inline unsigned long net_iov_virtual_addr(const struct net_iov *niov){ struct net_devmem_dmabuf_binding *binding = net_devmem_iov_binding(niov);
return (unsigned long)net_iov_idx(niov) << binding->niov_shift;}
static inline boolnet_devmem_dmabuf_binding_get(struct net_devmem_dmabuf_binding *binding){ return percpu_ref_tryget(&binding->ref);}
static inline voidnet_devmem_dmabuf_binding_put(struct net_devmem_dmabuf_binding *binding){ percpu_ref_put(&binding->ref);}
void net_devmem_net_iov_inc_ref(struct net_iov *niov);void net_devmem_net_iov_dec_ref(struct net_iov *niov);
void net_devmem_free_dmabuf(struct net_iov *ppiov);
struct net_devmem_dmabuf_binding *net_devmem_get_binding(struct sock *sk, unsigned int dmabuf_id);struct net_iov *net_devmem_get_niov_at(struct net_devmem_dmabuf_binding *binding, size_t addr, size_t *off, size_t *size);
#elsestruct net_devmem_dmabuf_binding;
static inline voidnet_devmem_dmabuf_binding_put(struct net_devmem_dmabuf_binding *binding){}
static inline void net_devmem_net_iov_inc_ref(struct net_iov *niov){}
static inline void net_devmem_net_iov_dec_ref(struct net_iov *niov){}
static inline struct net_devmem_dmabuf_binding *net_devmem_bind_dmabuf(struct net_device *dev, void *vdev, struct device *dma_dev, enum dma_data_direction direction, unsigned int dmabuf_fd, unsigned int niov_shift, struct netdev_nl_sock *priv, const struct sock *nl_sk, struct netlink_ext_ack *extack){ return ERR_PTR(-EOPNOTSUPP);}
static inline struct net_devmem_dmabuf_binding *net_devmem_lookup_dmabuf(u32 id){ return NULL;}
static inline voidnet_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding){}
static inline intnet_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx, struct net_devmem_dmabuf_binding *binding, struct netlink_ext_ack *extack)
{ return -EOPNOTSUPP;}
static inline void net_devmem_free_dmabuf(struct net_iov *ppiov){}
static inline unsigned long net_iov_virtual_addr(const struct net_iov *niov){ return 0;}
static inline u32 net_devmem_iov_binding_id(const struct net_iov *niov){ return 0;}
static inline struct net_devmem_dmabuf_binding *net_devmem_get_binding(struct sock *sk, unsigned int dmabuf_id){ return ERR_PTR(-EOPNOTSUPP);}
static inline struct net_iov *net_devmem_get_niov_at(struct net_devmem_dmabuf_binding *binding, size_t addr, size_t *off, size_t *size){ return NULL;}
static inline struct net_devmem_dmabuf_binding *net_devmem_iov_binding(const struct net_iov *niov){ return NULL;}#endif
#endif /* _NET_DEVMEM_H */