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/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright(c) 2020 Intel Corporation. */
#ifndef XSK_BUFF_POOL_H_
#define XSK_BUFF_POOL_H_
#include <linux/if_xdp.h>
#include <linux/types.h>
#include <linux/dma-mapping.h>
#include <linux/bpf.h>
#include <net/xdp.h>
struct xsk_buff_pool;
struct xdp_rxq_info;
struct xsk_queue;
struct xdp_desc;
struct xdp_umem;
struct xdp_sock;
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;
u64 orig_addr;
struct list_head free_list_node;
};
struct xsk_dma_map {
dma_addr_t *dma_pages;
struct device *dev;
struct net_device *netdev;
refcount_t users;
struct list_head list; /* Protected by the RTNL_LOCK */
u32 dma_pages_cnt;
bool dma_need_sync;
};
struct xsk_buff_pool {
/* Members only used in the control path first. */
struct device *dev;
struct net_device *netdev;
struct list_head xsk_tx_list;
/* Protects modifications to the xsk_tx_list */
spinlock_t xsk_tx_list_lock;
refcount_t users;
struct xdp_umem *umem;
struct work_struct work;
struct list_head free_list;
u32 heads_cnt;
u16 queue_id;
/* Data path members as close to free_heads at the end as possible. */
struct xsk_queue *fq ____cacheline_aligned_in_smp;
struct xsk_queue *cq;
/* For performance reasons, each buff pool has its own array of dma_pages
* even when they are identical.
*/
dma_addr_t *dma_pages;
struct xdp_buff_xsk *heads;
struct xdp_desc *tx_descs;
u64 chunk_mask;
u64 addrs_cnt;
u32 free_list_cnt;
u32 dma_pages_cnt;
u32 free_heads_cnt;
u32 headroom;
u32 chunk_size;
u32 chunk_shift;
u32 frame_len;
u8 cached_need_wakeup;
bool uses_need_wakeup;
bool dma_need_sync;
bool unaligned;
void *addrs;
/* Mutual exclusion of the completion ring in the SKB mode. Two cases to protect:
* NAPI TX thread and sendmsg error paths in the SKB destructor callback and when
* sockets share a single cq when the same netdev and queue id is shared.
*/
spinlock_t cq_lock;
struct xdp_buff_xsk *free_heads[];
};
/* Masks for xdp_umem_page flags.
* The low 12-bits of the addr will be 0 since this is the page address, so we
* can use them for flags.
*/
#define XSK_NEXT_PG_CONTIG_SHIFT 0
#define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT)
/* AF_XDP core. */
struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
struct xdp_umem *umem);
int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev,
u16 queue_id, u16 flags);
int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs,
struct net_device *dev, u16 queue_id);
int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs);
void xp_destroy(struct xsk_buff_pool *pool);
void xp_get_pool(struct xsk_buff_pool *pool);
bool xp_put_pool(struct xsk_buff_pool *pool);
void xp_clear_dev(struct xsk_buff_pool *pool);
void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs);
void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs);
/* AF_XDP, and XDP core. */
void xp_free(struct xdp_buff_xsk *xskb);
static inline void xp_init_xskb_addr(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool,
u64 addr)
{
xskb->orig_addr = addr;
xskb->xdp.data_hard_start = pool->addrs + addr + pool->headroom;
}
static inline void xp_init_xskb_dma(struct xdp_buff_xsk *xskb, struct xsk_buff_pool *pool,
dma_addr_t *dma_pages, u64 addr)
{
xskb->frame_dma = (dma_pages[addr >> PAGE_SHIFT] & ~XSK_NEXT_PG_CONTIG_MASK) +
(addr & ~PAGE_MASK);
xskb->dma = xskb->frame_dma + pool->headroom + XDP_PACKET_HEADROOM;
}
/* 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);
u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max);
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);
static inline dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb)
{
return xskb->dma;
}
static inline dma_addr_t xp_get_frame_dma(struct xdp_buff_xsk *xskb)
{
return xskb->frame_dma;
}
void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb);
static inline void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb)
{
xp_dma_sync_for_cpu_slow(xskb);
}
void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma,
size_t size);
static inline void xp_dma_sync_for_device(struct xsk_buff_pool *pool,
dma_addr_t dma, size_t size)
{
if (!pool->dma_need_sync)
return;
xp_dma_sync_for_device_slow(pool, dma, size);
}
/* Masks for xdp_umem_page flags.
* The low 12-bits of the addr will be 0 since this is the page address, so we
* can use them for flags.
*/
#define XSK_NEXT_PG_CONTIG_SHIFT 0
#define XSK_NEXT_PG_CONTIG_MASK BIT_ULL(XSK_NEXT_PG_CONTIG_SHIFT)
static inline bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool,
u64 addr, u32 len)
{
bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE;
if (likely(!cross_pg))
return false;
if (pool->dma_pages_cnt) {
return !(pool->dma_pages[addr >> PAGE_SHIFT] &
XSK_NEXT_PG_CONTIG_MASK);
}
/* skb path */
return addr + len > pool->addrs_cnt;
}
static inline u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr)
{
return addr & pool->chunk_mask;
}
static inline u64 xp_unaligned_extract_addr(u64 addr)
{
return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
}
static inline u64 xp_unaligned_extract_offset(u64 addr)
{
return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
}
static inline u64 xp_unaligned_add_offset_to_addr(u64 addr)
{
return xp_unaligned_extract_addr(addr) +
xp_unaligned_extract_offset(addr);
}
static inline u32 xp_aligned_extract_idx(struct xsk_buff_pool *pool, u64 addr)
{
return xp_aligned_extract_addr(pool, addr) >> pool->chunk_shift;
}
static inline void xp_release(struct xdp_buff_xsk *xskb)
{
if (xskb->pool->unaligned)
xskb->pool->free_heads[xskb->pool->free_heads_cnt++] = xskb;
}
static inline u64 xp_get_handle(struct xdp_buff_xsk *xskb)
{
u64 offset = xskb->xdp.data - xskb->xdp.data_hard_start;
offset += xskb->pool->headroom;
if (!xskb->pool->unaligned)
return xskb->orig_addr + offset;
return xskb->orig_addr + (offset << XSK_UNALIGNED_BUF_OFFSET_SHIFT);
}
#endif /* XSK_BUFF_POOL_H_ */
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