diff options
author | Björn Töpel <bjorn.topel@intel.com> | 2020-05-20 21:20:53 +0200 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2020-05-21 17:31:26 -0700 |
commit | 2b43470add8c8ff1e1ee28dffc5c5df97e955d09 (patch) | |
tree | f2e61f5891abf48c657365a324d091cdf3922ff0 /include/net/xsk_buff_pool.h | |
parent | 89e4a376e3a3dab639a3947a6c7cf5d461d1aa4c (diff) |
xsk: Introduce AF_XDP buffer allocation API
In order to simplify AF_XDP zero-copy enablement for NIC driver
developers, a new AF_XDP buffer allocation API is added. The
implementation is based on a single core (single producer/consumer)
buffer pool for the AF_XDP UMEM.
A buffer is allocated using the xsk_buff_alloc() function, and
returned using xsk_buff_free(). If a buffer is disassociated with the
pool, e.g. when a buffer is passed to an AF_XDP socket, a buffer is
said to be released. Currently, the release function is only used by
the AF_XDP internals and not visible to the driver.
Drivers using this API should register the XDP memory model with the
new MEM_TYPE_XSK_BUFF_POOL type.
The API is defined in net/xdp_sock_drv.h.
The buffer type is struct xdp_buff, and follows the lifetime of
regular xdp_buffs, i.e. the lifetime of an xdp_buff is restricted to
a NAPI context. In other words, the API is not replacing xdp_frames.
In addition to introducing the API and implementations, the AF_XDP
core is migrated to use the new APIs.
rfc->v1: Fixed build errors/warnings for m68k and riscv. (kbuild test
robot)
Added headroom/chunk size getter. (Maxim/Björn)
v1->v2: Swapped SoBs. (Maxim)
v2->v3: Initialize struct xdp_buff member frame_sz. (Björn)
Add API to query the DMA address of a frame. (Maxim)
Do DMA sync for CPU till the end of the frame to handle
possible growth (frame_sz). (Maxim)
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200520192103.355233-6-bjorn.topel@gmail.com
Diffstat (limited to 'include/net/xsk_buff_pool.h')
-rw-r--r-- | include/net/xsk_buff_pool.h | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/include/net/xsk_buff_pool.h b/include/net/xsk_buff_pool.h new file mode 100644 index 000000000000..9f221b36e405 --- /dev/null +++ b/include/net/xsk_buff_pool.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright(c) 2020 Intel Corporation. */ + +#ifndef XSK_BUFF_POOL_H_ +#define XSK_BUFF_POOL_H_ + +#include <linux/types.h> +#include <linux/dma-mapping.h> +#include <net/xdp.h> + +struct xsk_buff_pool; +struct xdp_rxq_info; +struct xsk_queue; +struct xdp_desc; +struct device; +struct page; + +struct xdp_buff_xsk { + struct xdp_buff xdp; + dma_addr_t dma; + dma_addr_t frame_dma; + struct xsk_buff_pool *pool; + bool unaligned; + u64 orig_addr; + struct list_head free_list_node; +}; + +/* AF_XDP core. */ +struct xsk_buff_pool *xp_create(struct page **pages, u32 nr_pages, u32 chunks, + u32 chunk_size, u32 headroom, u64 size, + bool unaligned); +void xp_set_fq(struct xsk_buff_pool *pool, struct xsk_queue *fq); +void xp_destroy(struct xsk_buff_pool *pool); +void xp_release(struct xdp_buff_xsk *xskb); +u64 xp_get_handle(struct xdp_buff_xsk *xskb); +bool xp_validate_desc(struct xsk_buff_pool *pool, struct xdp_desc *desc); + +/* AF_XDP, and XDP core. */ +void xp_free(struct xdp_buff_xsk *xskb); + +/* AF_XDP ZC drivers, via xdp_sock_buff.h */ +void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq); +int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, + unsigned long attrs, struct page **pages, u32 nr_pages); +void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs); +struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool); +bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count); +void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr); +dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr); +dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb); +dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb); +void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb); +void xp_dma_sync_for_device(struct xsk_buff_pool *pool, dma_addr_t dma, + size_t size); + +#endif /* XSK_BUFF_POOL_H_ */ |