[linux-block.git] / include / net / page_pool.h

/* SPDX-License-Identifier: GPL-2.0
 *
 * page_pool.h
 *	Author:	Jesper Dangaard Brouer <netoptimizer@brouer.com>
 *	Copyright (C) 2016 Red Hat, Inc.
 */

/**
 * DOC: page_pool allocator
 *
 * This page_pool allocator is optimized for the XDP mode that
 * uses one-frame-per-page, but have fallbacks that act like the
 * regular page allocator APIs.
 *
 * Basic use involve replacing alloc_pages() calls with the
 * page_pool_alloc_pages() call.  Drivers should likely use
 * page_pool_dev_alloc_pages() replacing dev_alloc_pages().
 *
 * API keeps track of in-flight pages, in-order to let API user know
 * when it is safe to dealloactor page_pool object.  Thus, API users
 * must make sure to call page_pool_release_page() when a page is
 * "leaving" the page_pool.  Or call page_pool_put_page() where
 * appropiate.  For maintaining correct accounting.
 *
 * API user must only call page_pool_put_page() once on a page, as it
 * will either recycle the page, or in case of elevated refcnt, it
 * will release the DMA mapping and in-flight state accounting.  We
 * hope to lift this requirement in the future.
 */
#ifndef _NET_PAGE_POOL_H
#define _NET_PAGE_POOL_H

#include <linux/mm.h> /* Needed by ptr_ring */
#include <linux/ptr_ring.h>
#include <linux/dma-direction.h>

#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_PAGE_FRAG	BIT(2) /* for page frag feature */
#define PP_FLAG_ALL		(PP_FLAG_DMA_MAP |\
				 PP_FLAG_DMA_SYNC_DEV |\
				 PP_FLAG_PAGE_FRAG)

/*
 * 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 {
	unsigned int	flags;
	unsigned int	order;
	unsigned int	pool_size;
	int		nid;  /* Numa node id to allocate from pages from */
	struct device	*dev; /* device, for DMA pre-mapping purposes */
	enum dma_data_direction dma_dir; /* DMA mapping direction */
	unsigned int	max_len; /* max DMA sync memory size */
	unsigned int	offset;  /* DMA addr offset */
	void (*init_callback)(struct page *page, void *arg);
	void *init_arg;
};

#ifdef CONFIG_PAGE_POOL_STATS
struct page_pool_alloc_stats {
	u64 fast; /* fast path allocations */
	u64 slow; /* slow-path order 0 allocations */
	u64 slow_high_order; /* slow-path high order allocations */
	u64 empty; /* failed refills due to empty ptr ring, forcing
		    * slow path allocation
		    */
	u64 refill; /* allocations via successful refill */
	u64 waive;  /* failed refills due to numa zone mismatch */
};

struct page_pool_recycle_stats {
	u64 cached;	/* recycling placed page in the cache. */
	u64 cache_full; /* cache was full */
	u64 ring;	/* recycling placed page back into ptr ring */
	u64 ring_full;	/* page was released from page-pool because
			 * PTR ring was full.
			 */
	u64 released_refcnt; /* page released because of elevated
			      * refcnt
			      */
};

/* This struct wraps the above stats structs so users of the
 * page_pool_get_stats API can pass a single argument when requesting the
 * stats for the page pool.
 */
struct page_pool_stats {
	struct page_pool_alloc_stats alloc_stats;
	struct page_pool_recycle_stats recycle_stats;
};

int page_pool_ethtool_stats_get_count(void);
u8 *page_pool_ethtool_stats_get_strings(u8 *data);
u64 *page_pool_ethtool_stats_get(u64 *data, void *stats);

/*
 * Drivers that wish to harvest page pool stats and report them to users
 * (perhaps via ethtool, debugfs, or another mechanism) can allocate a
 * struct page_pool_stats call page_pool_get_stats to get stats for the specified pool.
 */
bool page_pool_get_stats(struct page_pool *pool,
			 struct page_pool_stats *stats);
#else

static inline int page_pool_ethtool_stats_get_count(void)
{
	return 0;
}

static inline u8 *page_pool_ethtool_stats_get_strings(u8 *data)
{
	return data;
}

static inline u64 *page_pool_ethtool_stats_get(u64 *data, void *stats)
{
	return data;
}

#endif

struct page_pool {
	struct page_pool_params p;

	struct delayed_work release_dw;
	void (*disconnect)(void *);
	unsigned long defer_start;
	unsigned long defer_warn;

	u32 pages_state_hold_cnt;
	unsigned int frag_offset;
	struct page *frag_page;
	long frag_users;

#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
	 * effeciently, 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;
};

struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp);

static inline struct page *page_pool_dev_alloc_pages(struct page_pool *pool)
{
	gfp_t gfp = (GFP_ATOMIC | __GFP_NOWARN);

	return page_pool_alloc_pages(pool, gfp);
}

struct page *page_pool_alloc_frag(struct page_pool *pool, unsigned int *offset,
				  unsigned int size, gfp_t gfp);

static inline struct page *page_pool_dev_alloc_frag(struct page_pool *pool,
						    unsigned int *offset,
						    unsigned int size)
{
	gfp_t gfp = (GFP_ATOMIC | __GFP_NOWARN);

	return page_pool_alloc_frag(pool, offset, size, gfp);
}

/* get the stored dma direction. A driver might decide to treat this locally and
 * avoid the extra cache line from page_pool to determine the direction
 */
static
inline enum dma_data_direction page_pool_get_dma_dir(struct page_pool *pool)
{
	return pool->p.dma_dir;
}

bool page_pool_return_skb_page(struct page *page);

struct page_pool *page_pool_create(const struct page_pool_params *params);

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 *),
			   struct xdp_mem_info *mem);
void page_pool_release_page(struct page_pool *pool, struct page *page);
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 *),
					 struct xdp_mem_info *mem)
{
}
static inline void page_pool_release_page(struct page_pool *pool,
					  struct page *page)
{
}

static inline void page_pool_put_page_bulk(struct page_pool *pool, void **data,
					   int count)
{
}
#endif

void page_pool_put_defragged_page(struct page_pool *pool, struct page *page,
				  unsigned int dma_sync_size,
				  bool allow_direct);

static inline void page_pool_fragment_page(struct page *page, long nr)
{
	atomic_long_set(&page->pp_frag_count, nr);
}

static inline long page_pool_defrag_page(struct page *page, long nr)
{
	long ret;

	/* If nr == pp_frag_count then we have cleared all remaining
	 * references to the page. No need to actually overwrite it, instead
	 * we can leave this to be overwritten by the calling function.
	 *
	 * The main advantage to doing this is that an atomic_read is
	 * generally a much cheaper operation than an atomic update,
	 * especially when dealing with a page that may be partitioned
	 * into only 2 or 3 pieces.
	 */
	if (atomic_long_read(&page->pp_frag_count) == nr)
		return 0;

	ret = atomic_long_sub_return(nr, &page->pp_frag_count);
	WARN_ON(ret < 0);
	return ret;
}

static inline bool page_pool_is_last_frag(struct page_pool *pool,
					  struct page *page)
{
	/* If fragments aren't enabled or count is 0 we were the last user */
	return !(pool->p.flags & PP_FLAG_PAGE_FRAG) ||
	       (page_pool_defrag_page(page, 1) == 0);
}

static inline void page_pool_put_page(struct page_pool *pool,
				      struct page *page,
				      unsigned int dma_sync_size,
				      bool allow_direct)
{
	/* When page_pool isn't compiled-in, net/core/xdp.c doesn't
	 * allow registering MEM_TYPE_PAGE_POOL, but shield linker.
	 */
#ifdef CONFIG_PAGE_POOL
	if (!page_pool_is_last_frag(pool, page))
		return;

	page_pool_put_defragged_page(pool, page, dma_sync_size, allow_direct);
#endif
}

/* Same as above but will try to sync the entire area pool->max_len */
static inline void page_pool_put_full_page(struct page_pool *pool,
					   struct page *page, bool allow_direct)
{
	page_pool_put_page(pool, page, -1, allow_direct);
}

/* Same as above but the caller must guarantee safe context. e.g NAPI */
static inline void page_pool_recycle_direct(struct page_pool *pool,
					    struct page *page)
{
	page_pool_put_full_page(pool, page, true);
}

#define PAGE_POOL_DMA_USE_PP_FRAG_COUNT	\
		(sizeof(dma_addr_t) > sizeof(unsigned long))

static inline dma_addr_t page_pool_get_dma_addr(struct page *page)
{
	dma_addr_t ret = page->dma_addr;

	if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT)
		ret |= (dma_addr_t)page->dma_addr_upper << 16 << 16;

	return ret;
}

static inline void page_pool_set_dma_addr(struct page *page, dma_addr_t addr)
{
	page->dma_addr = addr;
	if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT)
		page->dma_addr_upper = upper_32_bits(addr);
}

static inline bool is_page_pool_compiled_in(void)
{
#ifdef CONFIG_PAGE_POOL
	return true;
#else
	return false;
#endif
}

static inline bool page_pool_put(struct page_pool *pool)
{
	return refcount_dec_and_test(&pool->user_cnt);
}

/* Caller must provide appropriate safe context, e.g. NAPI. */
void page_pool_update_nid(struct page_pool *pool, int new_nid);
static inline void page_pool_nid_changed(struct page_pool *pool, int new_nid)
{
	if (unlikely(pool->p.nid != new_nid))
		page_pool_update_nid(pool, new_nid);
}

static inline void page_pool_ring_lock(struct page_pool *pool)
	__acquires(&pool->ring.producer_lock)
{
	if (in_serving_softirq())
		spin_lock(&pool->ring.producer_lock);
	else
		spin_lock_bh(&pool->ring.producer_lock);
}

static inline void page_pool_ring_unlock(struct page_pool *pool)
	__releases(&pool->ring.producer_lock)
{
	if (in_serving_softirq())
		spin_unlock(&pool->ring.producer_lock);
	else
		spin_unlock_bh(&pool->ring.producer_lock);
}

#endif /* _NET_PAGE_POOL_H */
Commit	Line	Data
ff7d6b27 JDB	1	/* SPDX-License-Identifier: GPL-2.0
	2	*
	3	* page_pool.h
	4	* Author: Jesper Dangaard Brouer <netoptimizer@brouer.com>
	5	* Copyright (C) 2016 Red Hat, Inc.
	6	*/
	7
	8	/**
	9	* DOC: page_pool allocator
	10	*
	11	* This page_pool allocator is optimized for the XDP mode that
	12	* uses one-frame-per-page, but have fallbacks that act like the
	13	* regular page allocator APIs.
	14	*
	15	* Basic use involve replacing alloc_pages() calls with the
	16	* page_pool_alloc_pages() call. Drivers should likely use
	17	* page_pool_dev_alloc_pages() replacing dev_alloc_pages().
	18	*
99c07c43 JDB	19	* API keeps track of in-flight pages, in-order to let API user know
	20	* when it is safe to dealloactor page_pool object. Thus, API users
	21	* must make sure to call page_pool_release_page() when a page is
	22	* "leaving" the page_pool. Or call page_pool_put_page() where
	23	* appropiate. For maintaining correct accounting.
ff7d6b27	24	*
99c07c43 JDB	25	* API user must only call page_pool_put_page() once on a page, as it
	26	* will either recycle the page, or in case of elevated refcnt, it
	27	* will release the DMA mapping and in-flight state accounting. We
	28	* hope to lift this requirement in the future.
ff7d6b27 JDB	29	*/
	30	#ifndef _NET_PAGE_POOL_H
	31	#define _NET_PAGE_POOL_H
	32
	33	#include <linux/mm.h> /* Needed by ptr_ring */
	34	#include <linux/ptr_ring.h>
	35	#include <linux/dma-direction.h>
	36
e68bc756 LB	37	#define PP_FLAG_DMA_MAP BIT(0) /* Should page_pool do the DMA
	38	* map/unmap
	39	*/
	40	#define PP_FLAG_DMA_SYNC_DEV BIT(1) /* If set all pages that the driver gets
	41	* from page_pool will be
	42	* DMA-synced-for-device according to
	43	* the length provided by the device
	44	* driver.
	45	* Please note DMA-sync-for-CPU is still
	46	* device driver responsibility
	47	*/
0e9d2a0a YL	48	#define PP_FLAG_PAGE_FRAG BIT(2) /* for page frag feature */
	49	#define PP_FLAG_ALL (PP_FLAG_DMA_MAP \|\
	50	PP_FLAG_DMA_SYNC_DEV \|\
	51	PP_FLAG_PAGE_FRAG)
ff7d6b27 JDB	52
	53	/*
	54	* Fast allocation side cache array/stack
	55	*
	56	* The cache size and refill watermark is related to the network
	57	* use-case. The NAPI budget is 64 packets. After a NAPI poll the RX
	58	* ring is usually refilled and the max consumed elements will be 64,
	59	* thus a natural max size of objects needed in the cache.
	60	*
	61	* Keeping room for more objects, is due to XDP_DROP use-case. As
	62	* XDP_DROP allows the opportunity to recycle objects directly into
	63	* this array, as it shares the same softirq/NAPI protection. If
	64	* cache is already full (or partly full) then the XDP_DROP recycles
	65	* would have to take a slower code path.
	66	*/
	67	#define PP_ALLOC_CACHE_SIZE 128
	68	#define PP_ALLOC_CACHE_REFILL 64
	69	struct pp_alloc_cache {
	70	u32 count;
be5dba25	71	struct page *cache[PP_ALLOC_CACHE_SIZE];
ff7d6b27 JDB	72	};
	73
	74	struct page_pool_params {
	75	unsigned int flags;
	76	unsigned int order;
	77	unsigned int pool_size;
	78	int nid; /* Numa node id to allocate from pages from */
	79	struct device dev; / device, for DMA pre-mapping purposes */
	80	enum dma_data_direction dma_dir; /* DMA mapping direction */
e68bc756 LB	81	unsigned int max_len; /* max DMA sync memory size */
e68bc756 LB	82	unsigned int offset; /* DMA addr offset */
35b2e549 THJ	83	void (init_callback)(struct page page, void *arg);
35b2e549 THJ	84	void *init_arg;
ff7d6b27 JDB	85	};
ff7d6b27 JDB	86
8610037e JD	87	#ifdef CONFIG_PAGE_POOL_STATS
	88	struct page_pool_alloc_stats {
	89	u64 fast; /* fast path allocations */
	90	u64 slow; /* slow-path order 0 allocations */
	91	u64 slow_high_order; /* slow-path high order allocations */
	92	u64 empty; /* failed refills due to empty ptr ring, forcing
	93	* slow path allocation
	94	*/
	95	u64 refill; /* allocations via successful refill */
	96	u64 waive; /* failed refills due to numa zone mismatch */
	97	};
ad6fa1e1 JD	98
	99	struct page_pool_recycle_stats {
	100	u64 cached; /* recycling placed page in the cache. */
	101	u64 cache_full; /* cache was full */
	102	u64 ring; /* recycling placed page back into ptr ring */
	103	u64 ring_full; /* page was released from page-pool because
	104	* PTR ring was full.
	105	*/
	106	u64 released_refcnt; /* page released because of elevated
	107	* refcnt
	108	*/
	109	};
6b95e338 JD	110
	111	/* This struct wraps the above stats structs so users of the
	112	* page_pool_get_stats API can pass a single argument when requesting the
	113	* stats for the page pool.
	114	*/
	115	struct page_pool_stats {
	116	struct page_pool_alloc_stats alloc_stats;
	117	struct page_pool_recycle_stats recycle_stats;
	118	};
	119
f3c5264f LB	120	int page_pool_ethtool_stats_get_count(void);
	121	u8 page_pool_ethtool_stats_get_strings(u8 data);
	122	u64 page_pool_ethtool_stats_get(u64 data, void *stats);
	123
6b95e338 JD	124	/*
	125	* Drivers that wish to harvest page pool stats and report them to users
	126	* (perhaps via ethtool, debugfs, or another mechanism) can allocate a
	127	* struct page_pool_stats call page_pool_get_stats to get stats for the specified pool.
	128	*/
	129	bool page_pool_get_stats(struct page_pool *pool,
	130	struct page_pool_stats *stats);
f3c5264f LB	131	#else
	132
	133	static inline int page_pool_ethtool_stats_get_count(void)
	134	{
	135	return 0;
	136	}
	137
	138	static inline u8 page_pool_ethtool_stats_get_strings(u8 data)
	139	{
	140	return data;
	141	}
	142
	143	static inline u64 page_pool_ethtool_stats_get(u64 data, void *stats)
	144	{
	145	return data;
	146	}
	147
8610037e JD	148	#endif
8610037e JD	149
ff7d6b27	150	struct page_pool {
ff7d6b27 JDB	151	struct page_pool_params p;
ff7d6b27 JDB	152
c3f812ce JL	153	struct delayed_work release_dw;
	154	void (disconnect)(void );
	155	unsigned long defer_start;
	156	unsigned long defer_warn;
	157
	158	u32 pages_state_hold_cnt;
53e0961d YL	159	unsigned int frag_offset;
	160	struct page *frag_page;
	161	long frag_users;
8610037e JD	162
	163	#ifdef CONFIG_PAGE_POOL_STATS
	164	/* these stats are incremented while in softirq context */
	165	struct page_pool_alloc_stats alloc_stats;
	166	#endif
64693ec7	167	u32 xdp_mem_id;
99c07c43	168
ff7d6b27 JDB	169	/*
	170	* Data structure for allocation side
	171	*
	172	* Drivers allocation side usually already perform some kind
	173	* of resource protection. Piggyback on this protection, and
	174	* require driver to protect allocation side.
	175	*
	176	* For NIC drivers this means, allocate a page_pool per
	177	* RX-queue. As the RX-queue is already protected by
	178	* Softirq/BH scheduling and napi_schedule. NAPI schedule
	179	* guarantee that a single napi_struct will only be scheduled
	180	* on a single CPU (see napi_schedule).
	181	*/
	182	struct pp_alloc_cache alloc ____cacheline_aligned_in_smp;
	183
	184	/* Data structure for storing recycled pages.
	185	*
	186	* Returning/freeing pages is more complicated synchronization
	187	* wise, because free's can happen on remote CPUs, with no
	188	* association with allocation resource.
	189	*
	190	* Use ptr_ring, as it separates consumer and producer
	191	* effeciently, it a way that doesn't bounce cache-lines.
	192	*
	193	* TODO: Implement bulk return pages into this structure.
	194	*/
	195	struct ptr_ring ring;
99c07c43	196
ad6fa1e1 JD	197	#ifdef CONFIG_PAGE_POOL_STATS
	198	/* recycle stats are per-cpu to avoid locking */
	199	struct page_pool_recycle_stats __percpu *recycle_stats;
	200	#endif
99c07c43	201	atomic_t pages_state_release_cnt;
1da4bbef IK	202
	203	/* A page_pool is strictly tied to a single RX-queue being
	204	* protected by NAPI, due to above pp_alloc_cache. This
	205	* refcnt serves purpose is to simplify drivers error handling.
	206	*/
	207	refcount_t user_cnt;
7c9e6942 JDB	208
7c9e6942 JDB	209	u64 destroy_cnt;
ff7d6b27 JDB	210	};
	211
	212	struct page page_pool_alloc_pages(struct page_pool pool, gfp_t gfp);
	213
	214	static inline struct page page_pool_dev_alloc_pages(struct page_pool pool)
	215	{
	216	gfp_t gfp = (GFP_ATOMIC \| __GFP_NOWARN);
	217
	218	return page_pool_alloc_pages(pool, gfp);
	219	}
	220
53e0961d YL	221	struct page page_pool_alloc_frag(struct page_pool pool, unsigned int *offset,
	222	unsigned int size, gfp_t gfp);
	223
	224	static inline struct page page_pool_dev_alloc_frag(struct page_pool pool,
	225	unsigned int *offset,
	226	unsigned int size)
	227	{
	228	gfp_t gfp = (GFP_ATOMIC \| __GFP_NOWARN);
	229
	230	return page_pool_alloc_frag(pool, offset, size, gfp);
	231	}
	232
bb005f2a IA	233	/* get the stored dma direction. A driver might decide to treat this locally and
	234	* avoid the extra cache line from page_pool to determine the direction
	235	*/
	236	static
	237	inline enum dma_data_direction page_pool_get_dma_dir(struct page_pool *pool)
	238	{
	239	return pool->p.dma_dir;
	240	}
	241
6a5bcd84 IA	242	bool page_pool_return_skb_page(struct page *page);
6a5bcd84 IA	243
ff7d6b27 JDB	244	struct page_pool page_pool_create(const struct page_pool_params params);
ff7d6b27 JDB	245
64693ec7 THJ	246	struct xdp_mem_info;
64693ec7 THJ	247
e54cfd7e	248	#ifdef CONFIG_PAGE_POOL
c3f812ce	249	void page_pool_destroy(struct page_pool *pool);
64693ec7 THJ	250	void page_pool_use_xdp_mem(struct page_pool pool, void (disconnect)(void *),
64693ec7 THJ	251	struct xdp_mem_info *mem);
458de8a9	252	void page_pool_release_page(struct page_pool pool, struct page page);
78862447 LB	253	void page_pool_put_page_bulk(struct page_pool pool, void *data,
78862447 LB	254	int count);
c3f812ce	255	#else
1da4bbef IK	256	static inline void page_pool_destroy(struct page_pool *pool)
1da4bbef IK	257	{
c3f812ce	258	}
1da4bbef	259
c3f812ce	260	static inline void page_pool_use_xdp_mem(struct page_pool *pool,
64693ec7 THJ	261	void (disconnect)(void ),
64693ec7 THJ	262	struct xdp_mem_info *mem)
c3f812ce	263	{
1da4bbef	264	}
458de8a9 IA	265	static inline void page_pool_release_page(struct page_pool *pool,
	266	struct page *page)
	267	{
	268	}
78862447 LB	269
	270	static inline void page_pool_put_page_bulk(struct page_pool pool, void *data,
	271	int count)
	272	{
	273	}
c3f812ce	274	#endif
1da4bbef	275
52cc6ffc AD	276	void page_pool_put_defragged_page(struct page_pool pool, struct page page,
	277	unsigned int dma_sync_size,
	278	bool allow_direct);
ff7d6b27	279
52cc6ffc AD	280	static inline void page_pool_fragment_page(struct page *page, long nr)
	281	{
	282	atomic_long_set(&page->pp_frag_count, nr);
	283	}
	284
	285	static inline long page_pool_defrag_page(struct page *page, long nr)
	286	{
	287	long ret;
	288
	289	/* If nr == pp_frag_count then we have cleared all remaining
	290	* references to the page. No need to actually overwrite it, instead
	291	* we can leave this to be overwritten by the calling function.
	292	*
	293	* The main advantage to doing this is that an atomic_read is
	294	* generally a much cheaper operation than an atomic update,
	295	* especially when dealing with a page that may be partitioned
	296	* into only 2 or 3 pieces.
	297	*/
	298	if (atomic_long_read(&page->pp_frag_count) == nr)
	299	return 0;
	300
	301	ret = atomic_long_sub_return(nr, &page->pp_frag_count);
	302	WARN_ON(ret < 0);
	303	return ret;
	304	}
	305
	306	static inline bool page_pool_is_last_frag(struct page_pool *pool,
	307	struct page *page)
	308	{
	309	/* If fragments aren't enabled or count is 0 we were the last user */
	310	return !(pool->p.flags & PP_FLAG_PAGE_FRAG) \|\|
	311	(page_pool_defrag_page(page, 1) == 0);
	312	}
	313
	314	static inline void page_pool_put_page(struct page_pool *pool,
	315	struct page *page,
	316	unsigned int dma_sync_size,
	317	bool allow_direct)
ff7d6b27	318	{
57d0a1c1 JDB	319	/* When page_pool isn't compiled-in, net/core/xdp.c doesn't
	320	* allow registering MEM_TYPE_PAGE_POOL, but shield linker.
	321	*/
	322	#ifdef CONFIG_PAGE_POOL
52cc6ffc AD	323	if (!page_pool_is_last_frag(pool, page))
	324	return;
	325
	326	page_pool_put_defragged_page(pool, page, dma_sync_size, allow_direct);
57d0a1c1	327	#endif
ff7d6b27	328	}
458de8a9	329
52cc6ffc AD	330	/* Same as above but will try to sync the entire area pool->max_len */
	331	static inline void page_pool_put_full_page(struct page_pool *pool,
	332	struct page *page, bool allow_direct)
	333	{
	334	page_pool_put_page(pool, page, -1, allow_direct);
	335	}
	336
458de8a9	337	/* Same as above but the caller must guarantee safe context. e.g NAPI */
ff7d6b27 JDB	338	static inline void page_pool_recycle_direct(struct page_pool *pool,
	339	struct page *page)
	340	{
458de8a9	341	page_pool_put_full_page(pool, page, true);
6bf071bf JDB	342	}
6bf071bf JDB	343
f915b75b YL	344	#define PAGE_POOL_DMA_USE_PP_FRAG_COUNT \
	345	(sizeof(dma_addr_t) > sizeof(unsigned long))
	346
0afdeeed IA	347	static inline dma_addr_t page_pool_get_dma_addr(struct page *page)
0afdeeed IA	348	{
f915b75b YL	349	dma_addr_t ret = page->dma_addr;
	350
	351	if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT)
	352	ret \|= (dma_addr_t)page->dma_addr_upper << 16 << 16;
	353
	354	return ret;
9ddb3c14 MWO	355	}
	356
	357	static inline void page_pool_set_dma_addr(struct page *page, dma_addr_t addr)
	358	{
0e9d2a0a	359	page->dma_addr = addr;
f915b75b YL	360	if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT)
f915b75b YL	361	page->dma_addr_upper = upper_32_bits(addr);
0e9d2a0a YL	362	}
0e9d2a0a YL	363
57d0a1c1 JDB	364	static inline bool is_page_pool_compiled_in(void)
	365	{
	366	#ifdef CONFIG_PAGE_POOL
	367	return true;
	368	#else
	369	return false;
	370	#endif
	371	}
	372
1da4bbef IK	373	static inline bool page_pool_put(struct page_pool *pool)
	374	{
	375	return refcount_dec_and_test(&pool->user_cnt);
	376	}
	377
bc836748 SM	378	/* Caller must provide appropriate safe context, e.g. NAPI. */
	379	void page_pool_update_nid(struct page_pool *pool, int new_nid);
	380	static inline void page_pool_nid_changed(struct page_pool *pool, int new_nid)
	381	{
	382	if (unlikely(pool->p.nid != new_nid))
	383	page_pool_update_nid(pool, new_nid);
	384	}
78862447 LB	385
	386	static inline void page_pool_ring_lock(struct page_pool *pool)
	387	__acquires(&pool->ring.producer_lock)
	388	{
	389	if (in_serving_softirq())
	390	spin_lock(&pool->ring.producer_lock);
	391	else
	392	spin_lock_bh(&pool->ring.producer_lock);
	393	}
	394
	395	static inline void page_pool_ring_unlock(struct page_pool *pool)
	396	__releases(&pool->ring.producer_lock)
	397	{
	398	if (in_serving_softirq())
	399	spin_unlock(&pool->ring.producer_lock);
	400	else
	401	spin_unlock_bh(&pool->ring.producer_lock);
	402	}
	403
ff7d6b27	404	#endif /* _NET_PAGE_POOL_H */