linux/net/core/gso_test.c
Willem de Bruijn e6daf129cc net: gso_test: support CONFIG_MAX_SKB_FRAGS up to 45
The test allocs a single page to hold all the frag_list skbs. This
is insufficient on kernels with CONFIG_MAX_SKB_FRAGS=45, due to the
increased skb_shared_info frags[] array length.

        gso_test_func: ASSERTION FAILED at net/core/gso_test.c:210
        Expected alloc_size <= ((1UL) << 12), but
            alloc_size == 5075 (0x13d3)
            ((1UL) << 12) == 4096 (0x1000)

Simplify the logic. Just allocate a page for each frag_list skb.

Fixes: 4688ecb138 ("net: expand skb_segment unit test with frag_list coverage")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-13 11:04:38 +00:00

275 lines
7.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
#include <kunit/test.h>
#include <linux/skbuff.h>
static const char hdr[] = "abcdefgh";
#define GSO_TEST_SIZE 1000
static void __init_skb(struct sk_buff *skb)
{
skb_reset_mac_header(skb);
memcpy(skb_mac_header(skb), hdr, sizeof(hdr));
/* skb_segment expects skb->data at start of payload */
skb_pull(skb, sizeof(hdr));
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
/* proto is arbitrary, as long as not ETH_P_TEB or vlan */
skb->protocol = htons(ETH_P_ATALK);
skb_shinfo(skb)->gso_size = GSO_TEST_SIZE;
}
enum gso_test_nr {
GSO_TEST_LINEAR,
GSO_TEST_NO_GSO,
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 {
enum gso_test_nr id;
const char *name;
/* input */
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;
const unsigned int *segs;
};
static struct gso_test_case cases[] = {
{
.id = GSO_TEST_NO_GSO,
.name = "no_gso",
.linear_len = GSO_TEST_SIZE,
.nr_segs = 1,
.segs = (const unsigned int[]) { GSO_TEST_SIZE },
},
{
.id = GSO_TEST_LINEAR,
.name = "linear",
.linear_len = GSO_TEST_SIZE + GSO_TEST_SIZE + 1,
.nr_segs = 3,
.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 1 },
},
{
.id = GSO_TEST_FRAGS,
.name = "frags",
.linear_len = GSO_TEST_SIZE,
.nr_frags = 2,
.frags = (const unsigned int[]) { GSO_TEST_SIZE, 1 },
.nr_segs = 3,
.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 1 },
},
{
.id = GSO_TEST_FRAGS_PURE,
.name = "frags_pure",
.nr_frags = 3,
.frags = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 2 },
.nr_segs = 3,
.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, 2 },
},
{
.id = GSO_TEST_GSO_PARTIAL,
.name = "gso_partial",
.linear_len = GSO_TEST_SIZE,
.nr_frags = 2,
.frags = (const unsigned int[]) { GSO_TEST_SIZE, 3 },
.nr_segs = 2,
.segs = (const unsigned int[]) { 2 * GSO_TEST_SIZE, 3 },
},
{
/* commit 89319d3801d1: frag_list on mss boundaries */
.id = GSO_TEST_FRAG_LIST,
.name = "frag_list",
.linear_len = GSO_TEST_SIZE,
.nr_frag_skbs = 2,
.frag_skbs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE },
.nr_segs = 3,
.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, GSO_TEST_SIZE },
},
{
.id = GSO_TEST_FRAG_LIST_PURE,
.name = "frag_list_pure",
.nr_frag_skbs = 2,
.frag_skbs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE },
.nr_segs = 2,
.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE },
},
{
/* commit 43170c4e0ba7: GRO of frag_list trains */
.id = GSO_TEST_FRAG_LIST_NON_UNIFORM,
.name = "frag_list_non_uniform",
.linear_len = GSO_TEST_SIZE,
.nr_frag_skbs = 4,
.frag_skbs = (const unsigned int[]) { GSO_TEST_SIZE, 1, GSO_TEST_SIZE, 2 },
.nr_segs = 4,
.segs = (const unsigned int[]) { GSO_TEST_SIZE, GSO_TEST_SIZE, GSO_TEST_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)
{
sprintf(desc, "%s", t->name);
}
KUNIT_ARRAY_PARAM(gso_test, cases, gso_test_case_to_desc);
static void gso_test_func(struct kunit *test)
{
const int shinfo_size = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
struct sk_buff *skb, *segs, *cur, *next, *last;
const struct gso_test_case *tcase;
netdev_features_t features;
struct page *page;
int i;
tcase = test->param_value;
page = alloc_page(GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, page);
skb = build_skb(page_address(page), sizeof(hdr) + tcase->linear_len + shinfo_size);
KUNIT_ASSERT_NOT_NULL(test, skb);
__skb_put(skb, sizeof(hdr) + tcase->linear_len);
__init_skb(skb);
if (tcase->nr_frags) {
unsigned int pg_off = 0;
page = alloc_page(GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, page);
page_ref_add(page, tcase->nr_frags - 1);
for (i = 0; i < tcase->nr_frags; i++) {
skb_fill_page_desc(skb, i, page, pg_off, tcase->frags[i]);
pg_off += tcase->frags[i];
}
KUNIT_ASSERT_LE(test, pg_off, PAGE_SIZE);
skb->data_len = pg_off;
skb->len += skb->data_len;
skb->truesize += skb->data_len;
}
if (tcase->frag_skbs) {
unsigned int total_size = 0, total_true_size = 0;
struct sk_buff *frag_skb, *prev = NULL;
for (i = 0; i < tcase->nr_frag_skbs; i++) {
unsigned int frag_size;
page = alloc_page(GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, page);
frag_size = tcase->frag_skbs[i];
frag_skb = build_skb(page_address(page),
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;
}
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));
goto free_gso_skb;
} else if (!segs) {
KUNIT_FAIL(test, "no segments");
goto free_gso_skb;
}
last = segs->prev;
for (cur = segs, i = 0; cur; cur = next, i++) {
next = cur->next;
KUNIT_ASSERT_EQ(test, cur->len, sizeof(hdr) + tcase->segs[i]);
/* segs have skb->data pointing to the mac header */
KUNIT_ASSERT_PTR_EQ(test, skb_mac_header(cur), cur->data);
KUNIT_ASSERT_PTR_EQ(test, skb_network_header(cur), cur->data + sizeof(hdr));
/* header was copied to all segs */
KUNIT_ASSERT_EQ(test, memcmp(skb_mac_header(cur), hdr, sizeof(hdr)), 0);
/* last seg can be found through segs->prev pointer */
if (!next)
KUNIT_ASSERT_PTR_EQ(test, cur, last);
consume_skb(cur);
}
KUNIT_ASSERT_EQ(test, i, tcase->nr_segs);
free_gso_skb:
consume_skb(skb);
}
static struct kunit_case gso_test_cases[] = {
KUNIT_CASE_PARAM(gso_test_func, gso_test_gen_params),
{}
};
static struct kunit_suite gso_test_suite = {
.name = "net_core_gso",
.test_cases = gso_test_cases,
};
kunit_test_suite(gso_test_suite);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("KUnit tests for segmentation offload");