Lorenzo Bianconi <lore...@kernel.org> writes:
Introduce the capability to allocate a xdp multi-buff in
bpf_prog_test_run_xdp routine. This is a preliminary patch to
introduce
the selftests for new xdp multi-buff ebpf helpers
Signed-off-by: Lorenzo Bianconi <lore...@kernel.org>
---
net/bpf/test_run.c | 51
++++++++++++++++++++++++++++++++++++++--------
1 file changed, 43 insertions(+), 8 deletions(-)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index bd291f5f539c..ec7286cd051b 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -617,44 +617,79 @@ int bpf_prog_test_run_xdp(struct bpf_prog
*prog, const union bpf_attr *kattr,
{
u32 tailroom = SKB_DATA_ALIGN(sizeof(struct
skb_shared_info));
u32 headroom = XDP_PACKET_HEADROOM;
- u32 size = kattr->test.data_size_in;
u32 repeat = kattr->test.repeat;
struct netdev_rx_queue *rxqueue;
+ struct skb_shared_info *sinfo;
struct xdp_buff xdp = {};
+ u32 max_data_sz, size;
u32 retval, duration;
- u32 max_data_sz;
+ int i, ret, data_len;
void *data;
- int ret;
if (kattr->test.ctx_in || kattr->test.ctx_out)
return -EINVAL;
- /* XDP have extra tailroom as (most) drivers use full page
*/
max_data_sz = 4096 - headroom - tailroom;
For the sake of consistency, can this 4096 be changed to PAGE_SIZE
?
Same as in
data_len = min_t(int, kattr->test.data_size_in - size,
PAGE_SIZE);
expression below
+ size = min_t(u32, kattr->test.data_size_in, max_data_sz);
+ data_len = size;
- 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))
return PTR_ERR(data);
xdp.data_hard_start = data;
xdp.data = data + headroom;
xdp.data_meta = xdp.data;
- xdp.data_end = xdp.data + size;
+ xdp.data_end = xdp.data + data_len;
xdp.frame_sz = headroom + max_data_sz + tailroom;
+ sinfo = xdp_get_shared_info_from_buff(&xdp);
+ 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) {
+ skb_frag_t *frag =
&sinfo->frags[sinfo->nr_frags];
+ struct page *page;
+ int data_len;
+
+ page = alloc_page(GFP_KERNEL);
+ if (!page) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ __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->nr_frags++;
+ size += data_len;
+ }
+ xdp.mb = 1;
+ }
+
rxqueue =
__netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev,
0);
xdp.rxq = &rxqueue->xdp_rxq;
bpf_prog_change_xdp(NULL, prog);
ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration,
true);
if (ret)
goto out;
+
if (xdp.data != data + headroom || xdp.data_end !=
xdp.data + size)
- size = xdp.data_end - xdp.data;
+ size += xdp.data_end - xdp.data - data_len;
Can we please drop the variable shadowing of data_len ? This is
confusing since the initial value of data_len is correct in the
`size` calculation, while its value inside the while loop it not.
This seem to be syntactically correct, but I think it's better
practice to avoid shadowing here.
+
ret = bpf_test_finish(kattr, uattr, xdp.data, size,
retval, duration);
out:
bpf_prog_change_xdp(prog, NULL);
+ for (i = 0; i < sinfo->nr_frags; i++)
+ __free_page(skb_frag_page(&sinfo->frags[i]));
kfree(data);
+
return ret;
}
