On 6/17/21 4:29 PM, Zvi Effron wrote:
Support passing a xdp_md via ctx_in/ctx_out in bpf_attr for BPF_PROG_TEST_RUN. The intended use case is to pass some XDP meta data to the test runs of XDP programs that are used as tail calls. For programs that use bpf_prog_test_run_xdp, support xdp_md input and output. Unlike with an actual xdp_md during a non-test run, data_meta must be 0 because it must point to the start of the provided user data. From the initial xdp_md, use data and data_end to adjust the pointers in the generated xdp_buff. All other non-zero fields are prohibited (with EINVAL). If the user has set ctx_out/ctx_size_out, copy the (potentially different) xdp_md back to the userspace. We require all fields of input xdp_md except the ones we explicitly support to be set to zero. The expectation is that in the future we might add support for more fields and we want to fail explicitly if the user runs the program on the kernel where we don't yet support them. Co-developed-by: Cody Haas <chaas@xxxxxxxxxxxxx> Signed-off-by: Cody Haas <chaas@xxxxxxxxxxxxx> Co-developed-by: Lisa Watanabe <lwatanabe@xxxxxxxxxxxxx> Signed-off-by: Lisa Watanabe <lwatanabe@xxxxxxxxxxxxx> Signed-off-by: Zvi Effron <zeffron@xxxxxxxxxxxxx>
Acked-by: Yonghong Song <yhs@xxxxxx>
