diff options
Diffstat (limited to 'net/core/page_pool.c')
| -rw-r--r-- | net/core/page_pool.c | 162 |
1 files changed, 128 insertions, 34 deletions
diff --git a/net/core/page_pool.c b/net/core/page_pool.c index f5e908c9e7ad..4011eb305cee 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -11,8 +11,10 @@ #include <linux/slab.h> #include <linux/device.h> +#include <net/netdev_lock.h> #include <net/netdev_rx_queue.h> #include <net/page_pool/helpers.h> +#include <net/page_pool/memory_provider.h> #include <net/xdp.h> #include <linux/dma-direction.h> @@ -25,6 +27,7 @@ #include <trace/events/page_pool.h> +#include "dev.h" #include "mp_dmabuf_devmem.h" #include "netmem_priv.h" #include "page_pool_priv.h" @@ -273,25 +276,26 @@ static int page_pool_init(struct page_pool *pool, /* Driver calling page_pool_create() also call page_pool_destroy() */ refcount_set(&pool->user_cnt, 1); - if (pool->dma_map) - get_device(pool->p.dev); + xa_init_flags(&pool->dma_mapped, XA_FLAGS_ALLOC1); if (pool->slow.flags & PP_FLAG_ALLOW_UNREADABLE_NETMEM) { - /* We rely on rtnl_lock()ing to make sure netdev_rx_queue - * configuration doesn't change while we're initializing - * the page_pool. - */ - ASSERT_RTNL(); + netdev_assert_locked(pool->slow.netdev); rxq = __netif_get_rx_queue(pool->slow.netdev, pool->slow.queue_idx); pool->mp_priv = rxq->mp_params.mp_priv; + pool->mp_ops = rxq->mp_params.mp_ops; } - if (pool->mp_priv) { + if (pool->mp_ops) { if (!pool->dma_map || !pool->dma_sync) return -EOPNOTSUPP; - err = mp_dmabuf_devmem_init(pool); + if (WARN_ON(!is_kernel_rodata((unsigned long)pool->mp_ops))) { + err = -EFAULT; + goto free_ptr_ring; + } + + err = pool->mp_ops->init(pool); if (err) { pr_warn("%s() mem-provider init failed %d\n", __func__, err); @@ -315,9 +319,7 @@ free_ptr_ring: static void page_pool_uninit(struct page_pool *pool) { ptr_ring_cleanup(&pool->ring, NULL); - - if (pool->dma_map) - put_device(pool->p.dev); + xa_destroy(&pool->dma_mapped); #ifdef CONFIG_PAGE_POOL_STATS if (!pool->system) @@ -458,13 +460,21 @@ page_pool_dma_sync_for_device(const struct page_pool *pool, netmem_ref netmem, u32 dma_sync_size) { - if (pool->dma_sync && dma_dev_need_sync(pool->p.dev)) - __page_pool_dma_sync_for_device(pool, netmem, dma_sync_size); + if (pool->dma_sync && dma_dev_need_sync(pool->p.dev)) { + rcu_read_lock(); + /* re-check under rcu_read_lock() to sync with page_pool_scrub() */ + if (pool->dma_sync) + __page_pool_dma_sync_for_device(pool, netmem, + dma_sync_size); + rcu_read_unlock(); + } } -static bool page_pool_dma_map(struct page_pool *pool, netmem_ref netmem) +static bool page_pool_dma_map(struct page_pool *pool, netmem_ref netmem, gfp_t gfp) { dma_addr_t dma; + int err; + u32 id; /* Setup DMA mapping: use 'struct page' area for storing DMA-addr * since dma_addr_t can be either 32 or 64 bits and does not always fit @@ -478,15 +488,30 @@ static bool page_pool_dma_map(struct page_pool *pool, netmem_ref netmem) if (dma_mapping_error(pool->p.dev, dma)) return false; - if (page_pool_set_dma_addr_netmem(netmem, dma)) + if (page_pool_set_dma_addr_netmem(netmem, dma)) { + WARN_ONCE(1, "unexpected DMA address, please report to netdev@"); goto unmap_failed; + } + + if (in_softirq()) + err = xa_alloc(&pool->dma_mapped, &id, netmem_to_page(netmem), + PP_DMA_INDEX_LIMIT, gfp); + else + err = xa_alloc_bh(&pool->dma_mapped, &id, netmem_to_page(netmem), + PP_DMA_INDEX_LIMIT, gfp); + if (err) { + WARN_ONCE(err != -ENOMEM, "couldn't track DMA mapping, please report to netdev@"); + goto unset_failed; + } + netmem_set_dma_index(netmem, id); page_pool_dma_sync_for_device(pool, netmem, pool->p.max_len); return true; +unset_failed: + page_pool_set_dma_addr_netmem(netmem, 0); unmap_failed: - WARN_ONCE(1, "unexpected DMA address, please report to netdev@"); dma_unmap_page_attrs(pool->p.dev, dma, PAGE_SIZE << pool->p.order, pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING); @@ -503,7 +528,7 @@ static struct page *__page_pool_alloc_page_order(struct page_pool *pool, if (unlikely(!page)) return NULL; - if (pool->dma_map && unlikely(!page_pool_dma_map(pool, page_to_netmem(page)))) { + if (pool->dma_map && unlikely(!page_pool_dma_map(pool, page_to_netmem(page), gfp))) { put_page(page); return NULL; } @@ -549,7 +574,7 @@ static noinline netmem_ref __page_pool_alloc_pages_slow(struct page_pool *pool, */ for (i = 0; i < nr_pages; i++) { netmem = pool->alloc.cache[i]; - if (dma_map && unlikely(!page_pool_dma_map(pool, netmem))) { + if (dma_map && unlikely(!page_pool_dma_map(pool, netmem, gfp))) { put_page(netmem_to_page(netmem)); continue; } @@ -587,8 +612,8 @@ netmem_ref page_pool_alloc_netmems(struct page_pool *pool, gfp_t gfp) return netmem; /* Slow-path: cache empty, do real allocation */ - if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_priv) - netmem = mp_dmabuf_devmem_alloc_netmems(pool, gfp); + if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_ops) + netmem = pool->mp_ops->alloc_netmems(pool, gfp); else netmem = __page_pool_alloc_pages_slow(pool, gfp); return netmem; @@ -651,6 +676,8 @@ void page_pool_clear_pp_info(netmem_ref netmem) static __always_inline void __page_pool_release_page_dma(struct page_pool *pool, netmem_ref netmem) { + struct page *old, *page = netmem_to_page(netmem); + unsigned long id; dma_addr_t dma; if (!pool->dma_map) @@ -659,6 +686,17 @@ static __always_inline void __page_pool_release_page_dma(struct page_pool *pool, */ return; + id = netmem_get_dma_index(netmem); + if (!id) + return; + + if (in_softirq()) + old = xa_cmpxchg(&pool->dma_mapped, id, page, NULL, 0); + else + old = xa_cmpxchg_bh(&pool->dma_mapped, id, page, NULL, 0); + if (old != page) + return; + dma = page_pool_get_dma_addr_netmem(netmem); /* When page is unmapped, it cannot be returned to our pool */ @@ -666,6 +704,7 @@ static __always_inline void __page_pool_release_page_dma(struct page_pool *pool, PAGE_SIZE << pool->p.order, pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING); page_pool_set_dma_addr_netmem(netmem, 0); + netmem_set_dma_index(netmem, 0); } /* Disconnects a page (from a page_pool). API users can have a need @@ -679,8 +718,8 @@ void page_pool_return_page(struct page_pool *pool, netmem_ref netmem) bool put; put = true; - if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_priv) - put = mp_dmabuf_devmem_release_page(pool, netmem); + if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_ops) + put = pool->mp_ops->release_netmem(pool, netmem); else __page_pool_release_page_dma(pool, netmem); @@ -800,6 +839,10 @@ static bool page_pool_napi_local(const struct page_pool *pool) const struct napi_struct *napi; u32 cpuid; + /* On PREEMPT_RT the softirq can be preempted by the consumer */ + if (IS_ENABLED(CONFIG_PREEMPT_RT)) + return false; + if (unlikely(!in_softirq())) return false; @@ -824,8 +867,8 @@ void page_pool_put_unrefed_netmem(struct page_pool *pool, netmem_ref netmem, if (!allow_direct) allow_direct = page_pool_napi_local(pool); - netmem = - __page_pool_put_page(pool, netmem, dma_sync_size, allow_direct); + netmem = __page_pool_put_page(pool, netmem, dma_sync_size, + allow_direct); if (netmem && !page_pool_recycle_in_ring(pool, netmem)) { /* Cache full, fallback to free pages */ recycle_stat_inc(pool, ring_full); @@ -1048,8 +1091,8 @@ static void __page_pool_destroy(struct page_pool *pool) page_pool_unlist(pool); page_pool_uninit(pool); - if (pool->mp_priv) { - mp_dmabuf_devmem_destroy(pool); + if (pool->mp_ops) { + pool->mp_ops->destroy(pool); static_branch_dec(&page_pool_mem_providers); } @@ -1075,8 +1118,29 @@ static void page_pool_empty_alloc_cache_once(struct page_pool *pool) static void page_pool_scrub(struct page_pool *pool) { + unsigned long id; + void *ptr; + page_pool_empty_alloc_cache_once(pool); - pool->destroy_cnt++; + if (!pool->destroy_cnt++ && pool->dma_map) { + if (pool->dma_sync) { + /* Disable page_pool_dma_sync_for_device() */ + pool->dma_sync = false; + + /* Make sure all concurrent returns that may see the old + * value of dma_sync (and thus perform a sync) have + * finished before doing the unmapping below. Skip the + * wait if the device doesn't actually need syncing, or + * if there are no outstanding mapped pages. + */ + if (dma_dev_need_sync(pool->p.dev) && + !xa_empty(&pool->dma_mapped)) + synchronize_net(); + } + + xa_for_each(&pool->dma_mapped, id, ptr) + __page_pool_release_page_dma(pool, page_to_netmem(ptr)); + } /* No more consumers should exist, but producers could still * be in-flight. @@ -1104,7 +1168,13 @@ static void page_pool_release_retry(struct work_struct *wq) int inflight; inflight = page_pool_release(pool); - if (!inflight) + /* In rare cases, a driver bug may cause inflight to go negative. + * Don't reschedule release if inflight is 0 or negative. + * - If 0, the page_pool has been destroyed + * - if negative, we will never recover + * in both cases no reschedule is necessary. + */ + if (inflight <= 0) return; /* Periodic warning for page pools the user can't see */ @@ -1140,11 +1210,7 @@ void page_pool_disable_direct_recycling(struct page_pool *pool) if (!pool->p.napi) return; - /* To avoid races with recycling and additional barriers make sure - * pool and NAPI are unlinked when NAPI is disabled. - */ - WARN_ON(!test_bit(NAPI_STATE_SCHED, &pool->p.napi->state)); - WARN_ON(READ_ONCE(pool->p.napi->list_owner) != -1); + napi_assert_will_not_race(pool->p.napi); mutex_lock(&page_pools_lock); WRITE_ONCE(pool->p.napi, NULL); @@ -1190,3 +1256,31 @@ void page_pool_update_nid(struct page_pool *pool, int new_nid) } } EXPORT_SYMBOL(page_pool_update_nid); + +bool net_mp_niov_set_dma_addr(struct net_iov *niov, dma_addr_t addr) +{ + return page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov), addr); +} + +/* Associate a niov with a page pool. Should follow with a matching + * net_mp_niov_clear_page_pool() + */ +void net_mp_niov_set_page_pool(struct page_pool *pool, struct net_iov *niov) +{ + netmem_ref netmem = net_iov_to_netmem(niov); + + page_pool_set_pp_info(pool, netmem); + + pool->pages_state_hold_cnt++; + trace_page_pool_state_hold(pool, netmem, pool->pages_state_hold_cnt); +} + +/* Disassociate a niov from a page pool. Should only be used in the + * ->release_netmem() path. + */ +void net_mp_niov_clear_page_pool(struct net_iov *niov) +{ + netmem_ref netmem = net_iov_to_netmem(niov); + + page_pool_clear_pp_info(netmem); +} |