.. kernel-doc:: net/core/page_pool.c
:identifiers: page_pool_create
-.. kernel-doc:: include/net/page_pool.h
+.. kernel-doc:: include/net/page_pool/types.h
:identifiers: struct page_pool_params
-.. kernel-doc:: include/net/page_pool.h
+.. kernel-doc:: include/net/page_pool/helpers.h
:identifiers: page_pool_put_page page_pool_put_full_page
page_pool_recycle_direct page_pool_dev_alloc_pages
page_pool_get_dma_addr page_pool_get_dma_dir
The API will fill in the provided struct page_pool_stats with
statistics about the page_pool.
-.. kernel-doc:: include/net/page_pool.h
+.. kernel-doc:: include/net/page_pool/types.h
:identifiers: struct page_pool_recycle_stats
struct page_pool_alloc_stats
struct page_pool_stats
S: Supported
F: Documentation/networking/page_pool.rst
-F: include/net/page_pool.h
+F: include/net/page_pool/
F: include/trace/events/page_pool.h
F: net/core/page_pool.c
#include <net/pkt_cls.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <linux/align.h>
#include <net/netdev_queues.h>
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
#include <linux/filter.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include "bnxt_hsi.h"
#include "bnxt.h"
#include "bnxt_xdp.h"
#include <linux/iopoll.h>
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
+#include <net/page_pool/helpers.h>
#include <net/xdp_sock_drv.h>
#define TSNEP_RX_OFFSET (max(NET_SKB_PAD, XDP_PACKET_HEADROOM) + NET_IP_ALIGN)
#include <linux/in.h>
#include <linux/ip.h>
#include <net/ip.h>
+#include <net/page_pool/helpers.h>
#include <net/selftests.h>
#include <net/tso.h>
#include <linux/tcp.h>
#include <net/gre.h>
#include <net/gro.h>
#include <net/ip6_checksum.h>
+#include <net/page_pool/helpers.h>
#include <net/pkt_cls.h>
#include <net/pkt_sched.h>
#include <net/tcp.h>
#include <linux/dim.h>
#include <linux/if_vlan.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <asm/barrier.h>
#include "hnae3.h"
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/tso.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/pkt_sched.h>
#include <linux/bpf_trace.h>
#include <linux/phy.h>
#include <linux/phylink.h>
#include <net/flow_offload.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <linux/bpf.h>
#include <net/xdp.h>
#include <uapi/linux/ppp_defs.h>
#include <net/ip.h>
#include <net/ipv6.h>
+#include <net/page_pool/helpers.h>
#include <net/tso.h>
#include <linux/bpf_trace.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
+#include <net/page_pool/helpers.h>
#include <net/tso.h>
#include <linux/bitfield.h>
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
#include <linux/bitfield.h>
+#include <net/page_pool/types.h>
#include "otx2_reg.h"
#include "otx2_common.h"
#include <linux/bitfield.h>
#include <net/dsa.h>
#include <net/dst_metadata.h>
+#include <net/page_pool/helpers.h>
#include "mtk_eth_soc.h"
#include "mtk_wed.h"
#include <linux/rhashtable.h>
#include <linux/dim.h>
#include <linux/bitfield.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <linux/bpf_trace.h>
#include "mtk_ppe.h"
#include "en/port.h"
#include "en_accel/en_accel.h"
#include "en_accel/ipsec.h"
+#include <net/page_pool/types.h>
#include <net/xdp_sock_drv.h>
static u8 mlx5e_mpwrq_min_page_shift(struct mlx5_core_dev *mdev)
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/* Copyright (c) 2020 Mellanox Technologies */
-#include <net/page_pool.h>
#include "en/txrx.h"
#include "en/params.h"
#include "en/trap.h"
#include "en/xdp.h"
#include "en/params.h"
#include <linux/bitfield.h>
+#include <net/page_pool/helpers.h>
int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk)
{
#include <linux/debugfs.h>
#include <linux/if_bridge.h>
#include <linux/filter.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <net/pkt_sched.h>
#include <net/xdp_sock_drv.h>
#include "eswitch.h"
#include <linux/bitmap.h>
#include <linux/filter.h>
#include <net/ip6_checksum.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/inet_ecn.h>
#include <net/gro.h>
#include <net/udp.h>
#include "en/port.h"
#ifdef CONFIG_PAGE_POOL_STATS
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#endif
static unsigned int stats_grps_num(struct mlx5e_priv *priv)
#include <linux/bpf.h>
#include <linux/filter.h>
+#include <net/page_pool/helpers.h>
#include "lan966x_main.h"
#include <linux/phy.h>
#include <linux/phylink.h>
#include <linux/ptp_clock_kernel.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <net/pkt_cls.h>
#include <net/pkt_sched.h>
#include <net/switchdev.h>
#include <net/checksum.h>
#include <net/ip6_checksum.h>
+#include <net/page_pool/helpers.h>
#include <net/xdp.h>
#include <net/mana/mana.h>
#include <linux/bpf_trace.h>
#include <net/tcp.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/ip6_checksum.h>
#define NETSEC_REG_SOFT_RST 0x104
#include <linux/ptp_clock_kernel.h>
#include <linux/net_tstamp.h>
#include <linux/reset.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <net/xdp.h>
#include <uapi/linux/bpf.h>
#include <linux/phylink.h>
#include <linux/udp.h>
#include <linux/bpf_trace.h>
+#include <net/page_pool/helpers.h>
#include <net/pkt_cls.h>
#include <net/xdp_sock_drv.h>
#include "stmmac_ptp.h"
#include <linux/if_vlan.h>
#include <linux/kmemleak.h>
#include <linux/sys_soc.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
#include <linux/sys_soc.h>
#include <net/switchdev.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/pkt_cls.h>
#include <net/devlink.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/skbuff.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/pkt_cls.h>
#include <net/pkt_sched.h>
#include <linux/etherdevice.h>
#include <net/ip6_checksum.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/inet_ecn.h>
#include <linux/iopoll.h>
#include <linux/sctp.h>
#include <linux/ptr_ring.h>
#include <linux/bpf_trace.h>
#include <linux/net_tstamp.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#define DRV_NAME "veth"
#define DRV_VERSION "1.0"
*/
#include <linux/sched.h>
#include <linux/of.h>
-#include <net/page_pool.h>
#include "mt76.h"
#define CHAN2G(_idx, _freq) { \
#include <linux/average.h>
#include <linux/soc/mediatek/mtk_wed.h>
#include <net/mac80211.h>
+#include <net/page_pool/helpers.h>
#include "util.h"
#include "testmode.h"
#include <linux/slab.h>
#include <net/ip.h>
#include <linux/bpf.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <linux/bpf_trace.h>
#include <xen/xen.h>
#include <linux/if_packet.h>
#include <linux/llist.h>
#include <net/flow.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
#include <linux/netfilter/nf_conntrack_common.h>
#endif
+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0
- *
- * page_pool.h
- * 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 call page_pool_put_page() where appropriate and only attach
- * the page to a page_pool-aware objects, like skbs marked for recycling.
- *
- * 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 - page pool parameters
- * @flags: PP_FLAG_DMA_MAP, PP_FLAG_DMA_SYNC_DEV, PP_FLAG_PAGE_FRAG
- * @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
- */
-struct page_pool_params {
- unsigned int flags;
- 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;
-/* 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;
-};
-
-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);
-
-/**
- * page_pool_dev_alloc_pages() - allocate a page.
- * @pool: pool from which to allocate
- *
- * Get a page from the page allocator or page_pool caches.
- */
-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);
-}
-
-/**
- * page_pool_get_dma_dir() - Retrieve the stored DMA direction.
- * @pool: pool from which page was allocated
- *
- * Get the stored dma direction. A driver might decide to store 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, bool napi_safe);
-
-struct page_pool *page_pool_create(const struct page_pool_params *params);
-
-struct xdp_mem_info;
-
-#ifdef CONFIG_PAGE_POOL
-void page_pool_unlink_napi(struct page_pool *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_put_page_bulk(struct page_pool *pool, void **data,
- int count);
-#else
-static inline void page_pool_unlink_napi(struct page_pool *pool)
-{
-}
-
-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_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);
-
-/* pp_frag_count represents the number of writers who can update the page
- * either by updating skb->data or via DMA mappings for the device.
- * We can't rely on the page refcnt for that as we don't know who might be
- * holding page references and we can't reliably destroy or sync DMA mappings
- * of the fragments.
- *
- * When pp_frag_count reaches 0 we can either recycle the page if the page
- * refcnt is 1 or return it back to the memory allocator and destroy any
- * mappings we have.
- */
-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);
-}
-
-/**
- * page_pool_put_page() - release a reference to a page pool page
- * @pool: pool from which page was allocated
- * @page: page to release a reference on
- * @dma_sync_size: how much of the page may have been touched by the device
- * @allow_direct: released by the consumer, allow lockless caching
- *
- * The outcome of this depends on the page refcnt. If the driver bumps
- * the refcnt > 1 this will unmap the page. If the page refcnt is 1
- * the allocator owns the page and will try to recycle it in one of the pool
- * caches. If PP_FLAG_DMA_SYNC_DEV is set, the page will be synced for_device
- * using dma_sync_single_range_for_device().
- */
-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
-}
-
-/**
- * page_pool_put_full_page() - release a reference on a page pool page
- * @pool: pool from which page was allocated
- * @page: page to release a reference on
- * @allow_direct: released by the consumer, allow lockless caching
- *
- * Similar to page_pool_put_page(), but will DMA sync the entire memory area
- * as configured in &page_pool_params.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);
-}
-
-/**
- * page_pool_recycle_direct() - release a reference on a page pool page
- * @pool: pool from which page was allocated
- * @page: page to release a reference on
- *
- * Similar to page_pool_put_full_page() but caller must guarantee safe context
- * (e.g NAPI), since it will recycle the page directly into the pool fast cache.
- */
-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))
-
-/**
- * page_pool_get_dma_addr() - Retrieve the stored DMA address.
- * @page: page allocated from a page pool
- *
- * Fetch the DMA address of the page. The page pool to which the page belongs
- * must had been created with PP_FLAG_DMA_MAP.
- */
-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);
-}
-
-#endif /* _NET_PAGE_POOL_H */
--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * page_pool/helpers.h
+ * 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 call page_pool_put_page() where appropriate and only attach
+ * the page to a page_pool-aware objects, like skbs marked for recycling.
+ *
+ * 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_HELPERS_H
+#define _NET_PAGE_POOL_HELPERS_H
+
+#include <net/page_pool/types.h>
+
+#ifdef CONFIG_PAGE_POOL_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
+
+/**
+ * page_pool_dev_alloc_pages() - allocate a page.
+ * @pool: pool from which to allocate
+ *
+ * Get a page from the page allocator or page_pool caches.
+ */
+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);
+}
+
+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);
+}
+
+/**
+ * page_pool_get_dma_dir() - Retrieve the stored DMA direction.
+ * @pool: pool from which page was allocated
+ *
+ * Get the stored dma direction. A driver might decide to store 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;
+}
+
+/* pp_frag_count represents the number of writers who can update the page
+ * either by updating skb->data or via DMA mappings for the device.
+ * We can't rely on the page refcnt for that as we don't know who might be
+ * holding page references and we can't reliably destroy or sync DMA mappings
+ * of the fragments.
+ *
+ * When pp_frag_count reaches 0 we can either recycle the page if the page
+ * refcnt is 1 or return it back to the memory allocator and destroy any
+ * mappings we have.
+ */
+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);
+}
+
+/**
+ * page_pool_put_page() - release a reference to a page pool page
+ * @pool: pool from which page was allocated
+ * @page: page to release a reference on
+ * @dma_sync_size: how much of the page may have been touched by the device
+ * @allow_direct: released by the consumer, allow lockless caching
+ *
+ * The outcome of this depends on the page refcnt. If the driver bumps
+ * the refcnt > 1 this will unmap the page. If the page refcnt is 1
+ * the allocator owns the page and will try to recycle it in one of the pool
+ * caches. If PP_FLAG_DMA_SYNC_DEV is set, the page will be synced for_device
+ * using dma_sync_single_range_for_device().
+ */
+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
+}
+
+/**
+ * page_pool_put_full_page() - release a reference on a page pool page
+ * @pool: pool from which page was allocated
+ * @page: page to release a reference on
+ * @allow_direct: released by the consumer, allow lockless caching
+ *
+ * Similar to page_pool_put_page(), but will DMA sync the entire memory area
+ * as configured in &page_pool_params.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);
+}
+
+/**
+ * page_pool_recycle_direct() - release a reference on a page pool page
+ * @pool: pool from which page was allocated
+ * @page: page to release a reference on
+ *
+ * Similar to page_pool_put_full_page() but caller must guarantee safe context
+ * (e.g NAPI), since it will recycle the page directly into the pool fast cache.
+ */
+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))
+
+/**
+ * page_pool_get_dma_addr() - Retrieve the stored DMA address.
+ * @page: page allocated from a page pool
+ *
+ * Fetch the DMA address of the page. The page pool to which the page belongs
+ * must had been created with PP_FLAG_DMA_MAP.
+ */
+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 page_pool_put(struct page_pool *pool)
+{
+ return refcount_dec_and_test(&pool->user_cnt);
+}
+
+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);
+}
+
+#endif /* _NET_PAGE_POOL_HELPERS_H */
--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _NET_PAGE_POOL_TYPES_H
+#define _NET_PAGE_POOL_TYPES_H
+
+#include <linux/dma-direction.h>
+#include <linux/ptr_ring.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 - page pool parameters
+ * @flags: PP_FLAG_DMA_MAP, PP_FLAG_DMA_SYNC_DEV, PP_FLAG_PAGE_FRAG
+ * @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
+ */
+struct page_pool_params {
+ unsigned int flags;
+ 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;
+/* 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 p;
+
+ struct delayed_work release_dw;
+ void (*disconnect)(void *pool);
+ 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
+ * 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;
+};
+
+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);
+bool page_pool_return_skb_page(struct page *page, bool napi_safe);
+
+struct page_pool *page_pool_create(const struct page_pool_params *params);
+
+struct xdp_mem_info;
+
+#ifdef CONFIG_PAGE_POOL
+void page_pool_unlink_napi(struct page_pool *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_put_page_bulk(struct page_pool *pool, void **data,
+ int count);
+#else
+static inline void page_pool_unlink_napi(struct page_pool *pool)
+{
+}
+
+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_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 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 */
#include <linux/tracepoint.h>
#include <trace/events/mmflags.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
TRACE_EVENT(page_pool_release,
#include <net/sock.h>
#include <net/tcp.h>
#include <net/net_namespace.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <linux/error-injection.h>
#include <linux/smp.h>
#include <linux/sock_diag.h>
#include <linux/slab.h>
#include <linux/device.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/xdp.h>
#include <linux/dma-direction.h>
#include <net/mpls.h>
#include <net/mptcp.h>
#include <net/mctp.h>
-#include <net/page_pool.h>
+#include <net/page_pool/types.h>
#include <net/dropreason.h>
#include <linux/uaccess.h>
#include <linux/idr.h>
#include <linux/rhashtable.h>
#include <linux/bug.h>
-#include <net/page_pool.h>
+#include <net/page_pool/helpers.h>
#include <net/xdp.h>
#include <net/xdp_priv.h> /* struct xdp_mem_allocator */
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