1/* SPDX-License-Identifier: GPL-2.0 */
  2/* Copyright(c) 2020 Intel Corporation. */
  3
  4#ifndef XSK_BUFF_POOL_H_
  5#define XSK_BUFF_POOL_H_
  6
  7#include <linux/if_xdp.h>
  8#include <linux/types.h>
  9#include <linux/dma-mapping.h>
 10#include <net/xdp.h>
 11
 12struct xsk_buff_pool;
 13struct xdp_rxq_info;
 14struct xsk_queue;
 15struct xdp_desc;
 16struct device;
 17struct page;
 18
 19struct xdp_buff_xsk {
 20	struct xdp_buff xdp;
 21	dma_addr_t dma;
 22	dma_addr_t frame_dma;
 23	struct xsk_buff_pool *pool;
 24	bool unaligned;
 25	u64 orig_addr;
 26	struct list_head free_list_node;
 27};
 28
 29struct xsk_buff_pool {
 30	struct xsk_queue *fq;
 31	struct list_head free_list;
 32	dma_addr_t *dma_pages;
 33	struct xdp_buff_xsk *heads;
 34	u64 chunk_mask;
 35	u64 addrs_cnt;
 36	u32 free_list_cnt;
 37	u32 dma_pages_cnt;
 38	u32 heads_cnt;
 39	u32 free_heads_cnt;
 40	u32 headroom;
 41	u32 chunk_size;
 42	u32 frame_len;
 43	bool dma_need_sync;
 44	bool unaligned;
 45	void *addrs;
 46	struct device *dev;
 47	struct xdp_buff_xsk *free_heads[];
 48};
 49
 50/* AF_XDP core. */
 51struct xsk_buff_pool *xp_create(struct page **pages, u32 nr_pages, u32 chunks,
 52				u32 chunk_size, u32 headroom, u64 size,
 53				bool unaligned);
 54void xp_set_fq(struct xsk_buff_pool *pool, struct xsk_queue *fq);
 55void xp_destroy(struct xsk_buff_pool *pool);
 56void xp_release(struct xdp_buff_xsk *xskb);
 57
 58/* AF_XDP, and XDP core. */
 59void xp_free(struct xdp_buff_xsk *xskb);
 60
 61/* AF_XDP ZC drivers, via xdp_sock_buff.h */
 62void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq);
 63int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
 64	       unsigned long attrs, struct page **pages, u32 nr_pages);
 65void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs);
 66struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool);
 67bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count);
 68void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr);
 69dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr);
 70static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb)
 71{
 72	return xskb->dma;
 73}
 74
 75static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb)
 76{
 77	return xskb->frame_dma;
 78}
 79
 80void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb);
 81static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb)
 82{
 83	if (!xskb->pool->dma_need_sync)
 84		return;
 85
 86	xp_dma_sync_for_cpu_slow(xskb);
 87}
 88
 89void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma,
 90				 size_t size);
 91static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool,
 92					  dma_addr_t dma, size_t size)
 93{
 94	if (!pool->dma_need_sync)
 95		return;
 96
 97	xp_dma_sync_for_device_slow(pool, dma, size);
 98}
 99
100/* Masks for xdp_umem_page flags.
101 * The low 12-bits of the addr will be 0 since this is the page address, so we
102 * can use them for flags.
103 */
104#define XSK_NEXT_PG_CONTIG_SHIFT 0
105#define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT)
106
107static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool,
108						 u64 addr, u32 len)
109{
110	bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE;
111
112	if (pool->dma_pages_cnt && cross_pg) {
113		return !(pool->dma_pages[addr >> PAGE_SHIFT] &
114			 XSK_NEXT_PG_CONTIG_MASK);
115	}
116	return false;
117}
118
119static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr)
120{
121	return addr & pool->chunk_mask;
122}
123
124static inline u64 xp_unaligned_extract_addr(u64 addr)
125{
126	return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
127}
128
129static inline u64 xp_unaligned_extract_offset(u64 addr)
130{
131	return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
132}
133
134static inline u64 xp_unaligned_add_offset_to_addr(u64 addr)
135{
136	return xp_unaligned_extract_addr(addr) +
137		xp_unaligned_extract_offset(addr);
138}
139
140#endif /* XSK_BUFF_POOL_H_ */