linux/net/core/mp_dmabuf_devmem.h
Mina Almasry 0f92140468 memory-provider: dmabuf devmem memory provider
Implement a memory provider that allocates dmabuf devmem in the form of
net_iov.

The provider receives a reference to the struct netdev_dmabuf_binding
via the pool->mp_priv pointer. The driver needs to set this pointer for
the provider in the net_iov.

The provider obtains a reference on the netdev_dmabuf_binding which
guarantees the binding and the underlying mapping remains alive until
the provider is destroyed.

Usage of PP_FLAG_DMA_MAP is required for this memory provide such that
the page_pool can provide the driver with the dma-addrs of the devmem.

Support for PP_FLAG_DMA_SYNC_DEV is omitted for simplicity & p.order !=
0.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com>
Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20240910171458.219195-7-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11 20:44:31 -07:00

45 lines
964 B
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Dmabuf device memory provider.
*
* Authors: Mina Almasry <almasrymina@google.com>
*
*/
#ifndef _NET_MP_DMABUF_DEVMEM_H
#define _NET_MP_DMABUF_DEVMEM_H
#include <net/netmem.h>
#if defined(CONFIG_NET_DEVMEM)
int mp_dmabuf_devmem_init(struct page_pool *pool);
netmem_ref mp_dmabuf_devmem_alloc_netmems(struct page_pool *pool, gfp_t gfp);
void mp_dmabuf_devmem_destroy(struct page_pool *pool);
bool mp_dmabuf_devmem_release_page(struct page_pool *pool, netmem_ref netmem);
#else
static inline int mp_dmabuf_devmem_init(struct page_pool *pool)
{
return -EOPNOTSUPP;
}
static inline netmem_ref
mp_dmabuf_devmem_alloc_netmems(struct page_pool *pool, gfp_t gfp)
{
return 0;
}
static inline void mp_dmabuf_devmem_destroy(struct page_pool *pool)
{
}
static inline bool
mp_dmabuf_devmem_release_page(struct page_pool *pool, netmem_ref netmem)
{
return false;
}
#endif
#endif /* _NET_MP_DMABUF_DEVMEM_H */