Commit 1c194998 authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Alexei Starovoitov
Browse files

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: default avatarToke Hoiland-Jorgensen <toke@redhat.com>
Acked-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/b7c0e425a9287f00f601c4fc0de54738ec6ceeea.1642758637.git.lorenzo@kernel.org


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent be3d72a2

net/bpf/test_run.c

+45 −13
Original line number Diff line number Diff line
@@ -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 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, 
	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);