diff options
| -rw-r--r-- | include/linux/list.h | 20 | ||||
| -rw-r--r-- | include/linux/netdevice.h | 4 | ||||
| -rw-r--r-- | include/linux/poison.h | 2 | ||||
| -rw-r--r-- | include/net/page_pool/types.h | 4 | ||||
| -rw-r--r-- | net/core/page_pool_user.c | 84 |
5 files changed, 114 insertions, 0 deletions
diff --git a/include/linux/list.h b/include/linux/list.h index 1837caedf723..059aa1fff41e 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -1119,6 +1119,26 @@ static inline void hlist_move_list(struct hlist_head *old, old->first = NULL; } +/** + * hlist_splice_init() - move all entries from one list to another + * @from: hlist_head from which entries will be moved + * @last: last entry on the @from list + * @to: hlist_head to which entries will be moved + * + * @to can be empty, @from must contain at least @last. + */ +static inline void hlist_splice_init(struct hlist_head *from, + struct hlist_node *last, + struct hlist_head *to) +{ + if (to->first) + to->first->pprev = &last->next; + last->next = to->first; + to->first = from->first; + from->first->pprev = &to->first; + from->first = NULL; +} + #define hlist_entry(ptr, type, member) container_of(ptr,type,member) #define hlist_for_each(pos, head) \ diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e87caa81f70c..998c7aaa98b8 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2447,6 +2447,10 @@ struct net_device { #if IS_ENABLED(CONFIG_DPLL) struct dpll_pin *dpll_pin; #endif +#if IS_ENABLED(CONFIG_PAGE_POOL) + /** @page_pools: page pools created for this netdevice */ + struct hlist_head page_pools; +#endif }; #define to_net_dev(d) container_of(d, struct net_device, dev) diff --git a/include/linux/poison.h b/include/linux/poison.h index 851a855d3868..27a7dad17eef 100644 --- a/include/linux/poison.h +++ b/include/linux/poison.h @@ -83,6 +83,8 @@ /********** net/core/skbuff.c **********/ #define SKB_LIST_POISON_NEXT ((void *)(0x800 + POISON_POINTER_DELTA)) +/********** net/ **********/ +#define NET_PTR_POISON ((void *)(0x801 + POISON_POINTER_DELTA)) /********** kernel/bpf/ **********/ #define BPF_PTR_POISON ((void *)(0xeB9FUL + POISON_POINTER_DELTA)) diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h index c19f0df3bf0b..b258a571201e 100644 --- a/include/net/page_pool/types.h +++ b/include/net/page_pool/types.h @@ -5,6 +5,7 @@ #include <linux/dma-direction.h> #include <linux/ptr_ring.h> +#include <linux/types.h> #define PP_FLAG_DMA_MAP BIT(0) /* Should page_pool do the DMA * map/unmap @@ -48,6 +49,7 @@ struct pp_alloc_cache { * @pool_size: size of the ptr_ring * @nid: NUMA node id to allocate from pages from * @dev: device, for DMA pre-mapping purposes + * @netdev: netdev this pool will serve (leave as NULL if none or multiple) * @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 @@ -66,6 +68,7 @@ struct page_pool_params { unsigned int offset; ); struct_group_tagged(page_pool_params_slow, slow, + struct net_device *netdev; /* private: used by test code only */ void (*init_callback)(struct page *page, void *arg); void *init_arg; @@ -189,6 +192,7 @@ struct page_pool { struct page_pool_params_slow slow; /* User-facing fields, protected by page_pools_lock */ struct { + struct hlist_node list; u32 id; } user; }; diff --git a/net/core/page_pool_user.c b/net/core/page_pool_user.c index 630d1eeecf2a..e5c7f078fbd4 100644 --- a/net/core/page_pool_user.c +++ b/net/core/page_pool_user.c @@ -1,14 +1,31 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/mutex.h> +#include <linux/netdevice.h> #include <linux/xarray.h> +#include <net/net_debug.h> #include <net/page_pool/types.h> #include "page_pool_priv.h" static DEFINE_XARRAY_FLAGS(page_pools, XA_FLAGS_ALLOC1); +/* Protects: page_pools, netdevice->page_pools, pool->slow.netdev, pool->user. + * Ordering: inside rtnl_lock + */ static DEFINE_MUTEX(page_pools_lock); +/* Page pools are only reachable from user space (via netlink) if they are + * linked to a netdev at creation time. Following page pool "visibility" + * states are possible: + * - normal + * - user.list: linked to real netdev, netdev: real netdev + * - orphaned - real netdev has disappeared + * - user.list: linked to lo, netdev: lo + * - invisible - either (a) created without netdev linking, (b) unlisted due + * to error, or (c) the entire namespace which owned this pool disappeared + * - user.list: unhashed, netdev: unknown + */ + int page_pool_list(struct page_pool *pool) { static u32 id_alloc_next; @@ -20,6 +37,10 @@ int page_pool_list(struct page_pool *pool) if (err < 0) goto err_unlock; + if (pool->slow.netdev) + hlist_add_head(&pool->user.list, + &pool->slow.netdev->page_pools); + mutex_unlock(&page_pools_lock); return 0; @@ -32,5 +53,68 @@ void page_pool_unlist(struct page_pool *pool) { mutex_lock(&page_pools_lock); xa_erase(&page_pools, pool->user.id); + hlist_del(&pool->user.list); + mutex_unlock(&page_pools_lock); +} + +static void page_pool_unreg_netdev_wipe(struct net_device *netdev) +{ + struct page_pool *pool; + struct hlist_node *n; + + mutex_lock(&page_pools_lock); + hlist_for_each_entry_safe(pool, n, &netdev->page_pools, user.list) { + hlist_del_init(&pool->user.list); + pool->slow.netdev = NET_PTR_POISON; + } + mutex_unlock(&page_pools_lock); +} + +static void page_pool_unreg_netdev(struct net_device *netdev) +{ + struct page_pool *pool, *last; + struct net_device *lo; + + lo = dev_net(netdev)->loopback_dev; + + mutex_lock(&page_pools_lock); + last = NULL; + hlist_for_each_entry(pool, &netdev->page_pools, user.list) { + pool->slow.netdev = lo; + last = pool; + } + if (last) + hlist_splice_init(&netdev->page_pools, &last->user.list, + &lo->page_pools); mutex_unlock(&page_pools_lock); } + +static int +page_pool_netdevice_event(struct notifier_block *nb, + unsigned long event, void *ptr) +{ + struct net_device *netdev = netdev_notifier_info_to_dev(ptr); + + if (event != NETDEV_UNREGISTER) + return NOTIFY_DONE; + + if (hlist_empty(&netdev->page_pools)) + return NOTIFY_OK; + + if (netdev->ifindex != LOOPBACK_IFINDEX) + page_pool_unreg_netdev(netdev); + else + page_pool_unreg_netdev_wipe(netdev); + return NOTIFY_OK; +} + +static struct notifier_block page_pool_netdevice_nb = { + .notifier_call = page_pool_netdevice_event, +}; + +static int __init page_pool_user_init(void) +{ + return register_netdevice_notifier(&page_pool_netdevice_nb); +} + +subsys_initcall(page_pool_user_init); |