Set a 64-bit DMA mask on nsim_bus_dev, enable NETMEM_TX_DMA on the netdevsim net_device, and configure page_pool instances with PP_FLAG_ALLOW_UNREADABLE_NETMEM and queue_idx, plus PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV when CONFIG_HAS_DMA is set, so devmem bind-rx and bind-tx netlink operations can be tested against netdevsim in software selftests.
The pp_hold debugfs file allocates pages from the queue 0 page pool, so refuse it when that pool is backed by a memory provider, and take the netdev instance lock there so a concurrent bind-rx cannot swap the pool in between. The software PSP path checksums the payload when the peer does not decapsulate, so drop unreadable skbs there. Cc: Tariq Toukan <[email protected]> Cc: Kaifeng Wang <[email protected]> Assisted-by: LLM Signed-off-by: Mina Almasry <[email protected]> Reviewed-by: Dragos Tatulea <[email protected]> --- v3: - Only request page pool DMA mapping when CONFIG_HAS_DMA is set (Sashiko). - Refuse pp_hold on a page pool backed by a memory provider, under the netdev instance lock (Sashiko). - Drop unreadable skbs in the software PSP path when it would have to checksum the payload (Sashiko). --- drivers/net/netdevsim/bus.c | 1 + drivers/net/netdevsim/netdev.c | 27 +++++++++++++++++++++------ drivers/net/netdevsim/psp.c | 5 +++++ 3 files changed, 27 insertions(+), 6 deletions(-) diff --git a/drivers/net/netdevsim/bus.c b/drivers/net/netdevsim/bus.c index 5c55c308487b4..f87f5e037b6fb 100644 --- a/drivers/net/netdevsim/bus.c +++ b/drivers/net/netdevsim/bus.c @@ -462,6 +462,7 @@ nsim_bus_dev_new(unsigned int id, unsigned int port_count, unsigned int num_queu nsim_bus_dev->port_count = port_count; nsim_bus_dev->num_queues = num_queues; nsim_bus_dev->initial_net = current->nsproxy->net_ns; + dma_coerce_mask_and_coherent(&nsim_bus_dev->dev, DMA_BIT_MASK(64)); /* Disallow using nsim_bus_dev */ smp_store_release(&nsim_bus_dev->init, false); diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c index b4a99f3ceac60..357ea9e5623b3 100644 --- a/drivers/net/netdevsim/netdev.c +++ b/drivers/net/netdevsim/netdev.c @@ -414,19 +414,27 @@ static int nsim_poll(struct napi_struct *napi, int budget) return done; } -static int nsim_create_page_pool(struct page_pool **p, struct napi_struct *napi) +static int nsim_create_page_pool(struct net_device *dev, struct page_pool **p, + struct napi_struct *napi, int idx) { + struct netdevsim *ns = netdev_priv(dev); struct page_pool_params params = { .order = 0, .pool_size = NSIM_RING_SIZE, + .flags = PP_FLAG_ALLOW_UNREADABLE_NETMEM, + .max_len = PAGE_SIZE, .nid = NUMA_NO_NODE, - .dev = &napi->dev->dev, + .dev = &ns->nsim_bus_dev->dev, .napi = napi, .dma_dir = DMA_BIDIRECTIONAL, - .netdev = napi->dev, + .netdev = dev, + .queue_idx = idx, }; struct page_pool *pool; + if (IS_ENABLED(CONFIG_HAS_DMA)) + params.flags |= PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV; + pool = page_pool_create(¶ms); if (IS_ERR(pool)) return PTR_ERR(pool); @@ -450,7 +458,7 @@ static int nsim_init_napi(struct netdevsim *ns) for (i = 0; i < dev->num_rx_queues; i++) { rq = ns->rq[i]; - err = nsim_create_page_pool(&rq->page_pool, &rq->napi); + err = nsim_create_page_pool(dev, &rq->page_pool, &rq->napi, i); if (err) goto err_pp_destroy; } @@ -762,14 +770,16 @@ nsim_queue_mem_alloc(struct net_device *dev, if (ns->rq_reset_mode == 1) { if (!netif_running(ns->netdev)) return -ENETDOWN; - return nsim_create_page_pool(&qmem->pp, &ns->rq[idx]->napi); + return nsim_create_page_pool(dev, &qmem->pp, + &ns->rq[idx]->napi, idx); } qmem->rq = nsim_queue_alloc(); if (!qmem->rq) return -ENOMEM; - err = nsim_create_page_pool(&qmem->rq->page_pool, &qmem->rq->napi); + err = nsim_create_page_pool(dev, &qmem->rq->page_pool, &qmem->rq->napi, + idx); if (err) goto err_free; @@ -929,12 +939,15 @@ nsim_pp_hold_write(struct file *file, const char __user *data, return ret; rtnl_lock(); + netdev_lock(ns->netdev); ret = count; if (val == !!ns->page) goto exit; if (!netif_running(ns->netdev) && val) { ret = -ENETDOWN; + } else if (val && page_pool_is_unreadable(ns->rq[0]->page_pool)) { + ret = -EOPNOTSUPP; } else if (val) { ns->page = page_pool_dev_alloc_pages(ns->rq[0]->page_pool); if (!ns->page) @@ -946,6 +959,7 @@ nsim_pp_hold_write(struct file *file, const char __user *data, } exit: + netdev_unlock(ns->netdev); rtnl_unlock(); return ret; } @@ -1051,6 +1065,7 @@ static int nsim_init_netdevsim(struct netdevsim *ns) ns->netdev->netdev_ops = &nsim_netdev_ops; ns->netdev->stat_ops = &nsim_stat_ops; ns->netdev->queue_mgmt_ops = &nsim_queue_mgmt_ops; + ns->netdev->netmem_tx = NETMEM_TX_DMA; netdev_lockdep_set_classes(ns->netdev); err = nsim_udp_tunnels_info_create(ns->nsim_dev, ns->netdev); diff --git a/drivers/net/netdevsim/psp.c b/drivers/net/netdevsim/psp.c index 6b3532b5e360d..908cc0d391dc6 100644 --- a/drivers/net/netdevsim/psp.c +++ b/drivers/net/netdevsim/psp.c @@ -86,6 +86,11 @@ nsim_do_psp(struct sk_buff *skb, struct netdevsim *ns, __wsum csum; int udplen; + if (!skb_frags_readable(skb)) { + rc = SKB_DROP_REASON_PSP_OUTPUT; + goto out_unlock; + } + /* Do not decapsulate. Receive the skb with the udp and psp * headers still there as if this is a normal udp packet. * psp_dev_encapsulate() sets udp checksum to 0, so we need to -- 2.56.0.176.g3575e65682-goog
