From 1c194998252469cad00a08bd9ef0b99fd255c260 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Fri, 21 Jan 2022 11:09:58 +0100 Subject: [PATCH] bpf: introduce frags support to bpf_prog_test_run_xdp() Introduce the capability to allocate a xdp frags in bpf_prog_test_run_xdp routine. This is a preliminary patch to introduce the selftests for new xdp frags ebpf helpers Acked-by: Toke Hoiland-Jorgensen Acked-by: John Fastabend Signed-off-by: Lorenzo Bianconi Link: https://lore.kernel.org/r/b7c0e425a9287f00f601c4fc0de54738ec6ceeea.1642758637.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov --- net/bpf/test_run.c | 58 +++++++++++++++++++++++++++++++++++----------- 1 file changed, 45 insertions(+), 13 deletions(-) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 67f7c7d75944..394dd489b8f5 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -876,16 +876,16 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr) { u32 tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); - u32 headroom = XDP_PACKET_HEADROOM; u32 size = kattr->test.data_size_in; + u32 headroom = XDP_PACKET_HEADROOM; + u32 retval, duration, max_data_sz; u32 repeat = kattr->test.repeat; struct netdev_rx_queue *rxqueue; + struct skb_shared_info *sinfo; struct xdp_buff xdp = {}; - u32 retval, duration; + int i, ret = -EINVAL; struct xdp_md *ctx; - u32 max_data_sz; void *data; - int ret = -EINVAL; if (prog->expected_attach_type == BPF_XDP_DEVMAP || prog->expected_attach_type == BPF_XDP_CPUMAP) @@ -905,27 +905,60 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, headroom -= ctx->data; } - /* XDP have extra tailroom as (most) drivers use full page */ max_data_sz = 4096 - headroom - tailroom; + size = min_t(u32, size, max_data_sz); - data = bpf_test_init(kattr, kattr->test.data_size_in, - max_data_sz, headroom, tailroom); + data = bpf_test_init(kattr, size, max_data_sz, headroom, tailroom); if (IS_ERR(data)) { ret = PTR_ERR(data); goto free_ctx; } rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0); - xdp_init_buff(&xdp, headroom + max_data_sz + tailroom, - &rxqueue->xdp_rxq); + rxqueue->xdp_rxq.frag_size = headroom + max_data_sz + tailroom; + xdp_init_buff(&xdp, rxqueue->xdp_rxq.frag_size, &rxqueue->xdp_rxq); xdp_prepare_buff(&xdp, data, headroom, size, true); + sinfo = xdp_get_shared_info_from_buff(&xdp); ret = xdp_convert_md_to_buff(ctx, &xdp); if (ret) goto free_data; + if (unlikely(kattr->test.data_size_in > size)) { + void __user *data_in = u64_to_user_ptr(kattr->test.data_in); + + while (size < kattr->test.data_size_in) { + struct page *page; + skb_frag_t *frag; + int data_len; + + page = alloc_page(GFP_KERNEL); + if (!page) { + ret = -ENOMEM; + goto out; + } + + frag = &sinfo->frags[sinfo->nr_frags++]; + __skb_frag_set_page(frag, page); + + data_len = min_t(int, kattr->test.data_size_in - size, + PAGE_SIZE); + skb_frag_size_set(frag, data_len); + + if (copy_from_user(page_address(page), data_in + size, + data_len)) { + ret = -EFAULT; + goto out; + } + sinfo->xdp_frags_size += data_len; + size += data_len; + } + xdp_buff_set_frags_flag(&xdp); + } + if (repeat > 1) bpf_prog_change_xdp(NULL, prog); + ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true); /* We convert the xdp_buff back to an xdp_md before checking the return * code so the reference count of any held netdevice will be decremented @@ -935,10 +968,7 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, if (ret) goto out; - if (xdp.data_meta != data + headroom || - xdp.data_end != xdp.data_meta + size) - size = xdp.data_end - xdp.data_meta; - + size = xdp.data_end - xdp.data_meta + sinfo->xdp_frags_size; ret = bpf_test_finish(kattr, uattr, xdp.data_meta, size, retval, duration); if (!ret) @@ -949,6 +979,8 @@ out: if (repeat > 1) bpf_prog_change_xdp(prog, NULL); free_data: + for (i = 0; i < sinfo->nr_frags; i++) + __free_page(skb_frag_page(&sinfo->frags[i])); kfree(data); free_ctx: kfree(ctx);