/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _NET_PAGE_POOL_TYPES_H #define _NET_PAGE_POOL_TYPES_H #include #include #include #define PP_FLAG_DMA_MAP BIT(0) /* Should page_pool do the DMA * map/unmap */ #define PP_FLAG_DMA_SYNC_DEV BIT(1) /* If set all pages that the driver gets * from page_pool will be * DMA-synced-for-device according to * the length provided by the device * driver. * Please note DMA-sync-for-CPU is still * device driver responsibility */ #define PP_FLAG_SYSTEM_POOL BIT(2) /* Global system page_pool */ #define PP_FLAG_ALL (PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV | \ PP_FLAG_SYSTEM_POOL) /* * Fast allocation side cache array/stack * * The cache size and refill watermark is related to the network * use-case. The NAPI budget is 64 packets. After a NAPI poll the RX * ring is usually refilled and the max consumed elements will be 64, * thus a natural max size of objects needed in the cache. * * Keeping room for more objects, is due to XDP_DROP use-case. As * XDP_DROP allows the opportunity to recycle objects directly into * this array, as it shares the same softirq/NAPI protection. If * cache is already full (or partly full) then the XDP_DROP recycles * would have to take a slower code path. */ #define PP_ALLOC_CACHE_SIZE 128 #define PP_ALLOC_CACHE_REFILL 64 struct pp_alloc_cache { u32 count; struct page *cache[PP_ALLOC_CACHE_SIZE]; }; /** * struct page_pool_params - page pool parameters * @fast: params accessed frequently on hotpath * @order: 2^order pages on allocation * @pool_size: size of the ptr_ring * @nid: NUMA node id to allocate from pages from * @dev: device, for DMA pre-mapping purposes * @napi: NAPI which is the sole consumer of pages, otherwise NULL * @dma_dir: DMA mapping direction * @max_len: max DMA sync memory size for PP_FLAG_DMA_SYNC_DEV * @offset: DMA sync address offset for PP_FLAG_DMA_SYNC_DEV * @slow: params with slowpath access only (initialization and Netlink) * @netdev: netdev this pool will serve (leave as NULL if none or multiple) * @flags: PP_FLAG_DMA_MAP, PP_FLAG_DMA_SYNC_DEV, PP_FLAG_SYSTEM_POOL */ struct page_pool_params { struct_group_tagged(page_pool_params_fast, fast, unsigned int order; unsigned int pool_size; int nid; struct device *dev; struct napi_struct *napi; enum dma_data_direction dma_dir; unsigned int max_len; unsigned int offset; ); struct_group_tagged(page_pool_params_slow, slow, struct net_device *netdev; unsigned int flags; /* private: used by test code only */ void (*init_callback)(struct page *page, void *arg); void *init_arg; ); }; #ifdef CONFIG_PAGE_POOL_STATS /** * struct page_pool_alloc_stats - allocation statistics * @fast: successful fast path allocations * @slow: slow path order-0 allocations * @slow_high_order: slow path high order allocations * @empty: ptr ring is empty, so a slow path allocation was forced * @refill: an allocation which triggered a refill of the cache * @waive: pages obtained from the ptr ring that cannot be added to * the cache due to a NUMA mismatch */ struct page_pool_alloc_stats { u64 fast; u64 slow; u64 slow_high_order; u64 empty; u64 refill; u64 waive; }; /** * struct page_pool_recycle_stats - recycling (freeing) statistics * @cached: recycling placed page in the page pool cache * @cache_full: page pool cache was full * @ring: page placed into the ptr ring * @ring_full: page released from page pool because the ptr ring was full * @released_refcnt: page released (and not recycled) because refcnt > 1 */ struct page_pool_recycle_stats { u64 cached; u64 cache_full; u64 ring; u64 ring_full; u64 released_refcnt; }; /** * struct page_pool_stats - combined page pool use statistics * @alloc_stats: see struct page_pool_alloc_stats * @recycle_stats: see struct page_pool_recycle_stats * * Wrapper struct for combining page pool stats with different storage * requirements. */ struct page_pool_stats { struct page_pool_alloc_stats alloc_stats; struct page_pool_recycle_stats recycle_stats; }; #endif struct page_pool { struct page_pool_params_fast p; int cpuid; u32 pages_state_hold_cnt; bool has_init_callback:1; /* slow::init_callback is set */ bool dma_map:1; /* Perform DMA mapping */ bool dma_sync:1; /* Perform DMA sync */ #ifdef CONFIG_PAGE_POOL_STATS bool system:1; /* This is a global percpu pool */ #endif /* The following block must stay within one cacheline. On 32-bit * systems, sizeof(long) == sizeof(int), so that the block size is * ``3 * sizeof(long)``. On 64-bit systems, the actual size is * ``2 * sizeof(long) + sizeof(int)``. The closest pow-2 to both of * them is ``4 * sizeof(long)``, so just use that one for simplicity. * Having it aligned to a cacheline boundary may be excessive and * doesn't bring any good. */ __cacheline_group_begin(frag) __aligned(4 * sizeof(long)); long frag_users; struct page *frag_page; unsigned int frag_offset; __cacheline_group_end(frag); struct delayed_work release_dw; void (*disconnect)(void *pool); unsigned long defer_start; unsigned long defer_warn; #ifdef CONFIG_PAGE_POOL_STATS /* these stats are incremented while in softirq context */ struct page_pool_alloc_stats alloc_stats; #endif u32 xdp_mem_id; /* * Data structure for allocation side * * Drivers allocation side usually already perform some kind * of resource protection. Piggyback on this protection, and * require driver to protect allocation side. * * For NIC drivers this means, allocate a page_pool per * RX-queue. As the RX-queue is already protected by * Softirq/BH scheduling and napi_schedule. NAPI schedule * guarantee that a single napi_struct will only be scheduled * on a single CPU (see napi_schedule). */ struct pp_alloc_cache alloc ____cacheline_aligned_in_smp; /* Data structure for storing recycled pages. * * Returning/freeing pages is more complicated synchronization * wise, because free's can happen on remote CPUs, with no * association with allocation resource. * * Use ptr_ring, as it separates consumer and producer * efficiently, it a way that doesn't bounce cache-lines. * * TODO: Implement bulk return pages into this structure. */ struct ptr_ring ring; #ifdef CONFIG_PAGE_POOL_STATS /* recycle stats are per-cpu to avoid locking */ struct page_pool_recycle_stats __percpu *recycle_stats; #endif atomic_t pages_state_release_cnt; /* A page_pool is strictly tied to a single RX-queue being * protected by NAPI, due to above pp_alloc_cache. This * refcnt serves purpose is to simplify drivers error handling. */ refcount_t user_cnt; u64 destroy_cnt; /* Slow/Control-path information follows */ struct page_pool_params_slow slow; /* User-facing fields, protected by page_pools_lock */ struct { struct hlist_node list; u64 detach_time; u32 napi_id; u32 id; } user; }; struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp); struct page *page_pool_alloc_frag(struct page_pool *pool, unsigned int *offset, unsigned int size, gfp_t gfp); struct page_pool *page_pool_create(const struct page_pool_params *params); struct page_pool *page_pool_create_percpu(const struct page_pool_params *params, int cpuid); struct xdp_mem_info; #ifdef CONFIG_PAGE_POOL void page_pool_destroy(struct page_pool *pool); void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *), const struct xdp_mem_info *mem); void page_pool_put_page_bulk(struct page_pool *pool, void **data, int count); #else static inline void page_pool_destroy(struct page_pool *pool) { } static inline void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *), const struct xdp_mem_info *mem) { } static inline void page_pool_put_page_bulk(struct page_pool *pool, void **data, int count) { } #endif void page_pool_put_unrefed_page(struct page_pool *pool, struct page *page, unsigned int dma_sync_size, bool allow_direct); static inline bool is_page_pool_compiled_in(void) { #ifdef CONFIG_PAGE_POOL return true; #else return false; #endif } /* Caller must provide appropriate safe context, e.g. NAPI. */ void page_pool_update_nid(struct page_pool *pool, int new_nid); #endif /* _NET_PAGE_POOL_H */