Commit 4688ecb1 authored by Willem de Bruijn's avatar Willem de Bruijn Committed by David S. Miller
Browse files

net: expand skb_segment unit test with frag_list coverage 



Expand the test with these variants that use skb frag_list:

- GSO_TEST_FRAG_LIST:             frag_skb length is gso_size
- GSO_TEST_FRAG_LIST_PURE:        same, data exclusively in frag skbs
- GSO_TEST_FRAG_LIST_NON_UNIFORM: frag_skb length may vary
- GSO_TEST_GSO_BY_FRAGS:          frag_skb length defines gso_size,
                                  i.e., segs may have varying sizes.

Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
Reviewed-by: default avatarFlorian Westphal <fw@strlen.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1b4fa28a

net/core/gso_test.c

+92 −0
Original line number Diff line number Diff line
@@ -27,6 +27,10 @@ enum gso_test_nr { 
	GSO_TEST_FRAGS,

	GSO_TEST_FRAGS_PURE,

	GSO_TEST_GSO_PARTIAL,

	GSO_TEST_FRAG_LIST,

	GSO_TEST_FRAG_LIST_PURE,

	GSO_TEST_FRAG_LIST_NON_UNIFORM,

	GSO_TEST_GSO_BY_FRAGS,

};



struct gso_test_case {
@@ -37,6 +41,8 @@ struct gso_test_case { 
	unsigned int linear_len;

	unsigned int nr_frags;

	const unsigned int *frags;

	unsigned int nr_frag_skbs;

	const unsigned int *frag_skbs;



	/* output as expected */

	unsigned int nr_segs;
@@ -84,6 +90,48 @@ static struct gso_test_case cases[] = { 
		.nr_segs = 2,

		.segs = (const unsigned int[]) { 2 * gso_size, 3 },

	},

	{

		/* commit 89319d3801d1: frag_list on mss boundaries */

		.id = GSO_TEST_FRAG_LIST,

		.name = "frag_list",

		.linear_len = gso_size,

		.nr_frag_skbs = 2,

		.frag_skbs = (const unsigned int[]) { gso_size, gso_size },

		.nr_segs = 3,

		.segs = (const unsigned int[]) { gso_size, gso_size, gso_size },

	},

	{

		.id = GSO_TEST_FRAG_LIST_PURE,

		.name = "frag_list_pure",

		.nr_frag_skbs = 2,

		.frag_skbs = (const unsigned int[]) { gso_size, gso_size },

		.nr_segs = 2,

		.segs = (const unsigned int[]) { gso_size, gso_size },

	},

	{

		/* commit 43170c4e0ba7: GRO of frag_list trains */

		.id = GSO_TEST_FRAG_LIST_NON_UNIFORM,

		.name = "frag_list_non_uniform",

		.linear_len = gso_size,

		.nr_frag_skbs = 4,

		.frag_skbs = (const unsigned int[]) { gso_size, 1, gso_size, 2 },

		.nr_segs = 4,

		.segs = (const unsigned int[]) { gso_size, gso_size, gso_size, 3 },

	},

	{

		/* commit 3953c46c3ac7 ("sk_buff: allow segmenting based on frag sizes") and

		 * commit 90017accff61 ("sctp: Add GSO support")

		 *

		 * "there will be a cover skb with protocol headers and

		 *  children ones containing the actual segments"

		 */

		.id = GSO_TEST_GSO_BY_FRAGS,

		.name = "gso_by_frags",

		.nr_frag_skbs = 4,

		.frag_skbs = (const unsigned int[]) { 100, 200, 300, 400 },

		.nr_segs = 4,

		.segs = (const unsigned int[]) { 100, 200, 300, 400 },

	},

};



static void gso_test_case_to_desc(struct gso_test_case *t, char *desc)
@@ -131,10 +179,54 @@ static void gso_test_func(struct kunit *test) 
		skb->truesize += skb->data_len;

	}



	if (tcase->frag_skbs) {

		unsigned int total_size = 0, total_true_size = 0, alloc_size = 0;

		struct sk_buff *frag_skb, *prev = NULL;



		page = alloc_page(GFP_KERNEL);

		KUNIT_ASSERT_NOT_NULL(test, page);

		page_ref_add(page, tcase->nr_frag_skbs - 1);



		for (i = 0; i < tcase->nr_frag_skbs; i++) {

			unsigned int frag_size;



			frag_size = tcase->frag_skbs[i];

			frag_skb = build_skb(page_address(page) + alloc_size,

					     frag_size + shinfo_size);

			KUNIT_ASSERT_NOT_NULL(test, frag_skb);

			__skb_put(frag_skb, frag_size);



			if (prev)

				prev->next = frag_skb;

			else

				skb_shinfo(skb)->frag_list = frag_skb;

			prev = frag_skb;



			total_size += frag_size;

			total_true_size += frag_skb->truesize;

			alloc_size += frag_size + shinfo_size;

		}



		KUNIT_ASSERT_LE(test, alloc_size, PAGE_SIZE);



		skb->len += total_size;

		skb->data_len += total_size;

		skb->truesize += total_true_size;



		if (tcase->id == GSO_TEST_GSO_BY_FRAGS)

			skb_shinfo(skb)->gso_size = GSO_BY_FRAGS;

	}



	features = NETIF_F_SG | NETIF_F_HW_CSUM;

	if (tcase->id == GSO_TEST_GSO_PARTIAL)

		features |= NETIF_F_GSO_PARTIAL;



	/* TODO: this should also work with SG,

	 * rather than hit BUG_ON(i >= nfrags)

	 */

	if (tcase->id == GSO_TEST_FRAG_LIST_NON_UNIFORM)

		features &= ~NETIF_F_SG;



	segs = skb_segment(skb, features);

	if (IS_ERR(segs)) {

		KUNIT_FAIL(test, "segs error %lld", PTR_ERR(segs));