Re: [PATCH v2 2/4] selftests/bpf: test_progs/sockopt_sk: pass page size from userspace
From: Andrii Nakryiko <hidden>
Date: 2021-03-28 05:01:51
On Fri, Mar 26, 2021 at 5:24 AM Yauheni Kaliuta [off-list ref] wrote:
Since there is no convenient way for bpf program to get PAGE_SIZE from inside of the kernel, pass the value from userspace. Signed-off-by: Yauheni Kaliuta <redacted> ---
Acked-by: Andrii Nakryiko <andrii@kernel.org> But I'd also shorten the subject to: selftests/bpf: pass page size from userspace in sockopt_sk It's just as clear and doesn't include unnecessary prog_tests/ path.
quoted hunk ↗ jump to hunk
tools/testing/selftests/bpf/prog_tests/sockopt_sk.c | 2 ++ tools/testing/selftests/bpf/progs/sockopt_sk.c | 10 ++++------ 2 files changed, 6 insertions(+), 6 deletions(-)diff --git a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c index 114c1a622ffa..6a7cb5f23db2 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c +++ b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c@@ -201,6 +201,8 @@ static void run_test(int cgroup_fd) if (CHECK(!skel, "skel_load", "sockopt_sk skeleton failed\n")) goto cleanup; + skel->bss->page_size = getpagesize(); + skel->links._setsockopt = bpf_program__attach_cgroup(skel->progs._setsockopt, cgroup_fd); if (CHECK(IS_ERR(skel->links._setsockopt),diff --git a/tools/testing/selftests/bpf/progs/sockopt_sk.c b/tools/testing/selftests/bpf/progs/sockopt_sk.c index d3597f81e6e9..55dfbe53c24e 100644 --- a/tools/testing/selftests/bpf/progs/sockopt_sk.c +++ b/tools/testing/selftests/bpf/progs/sockopt_sk.c@@ -8,9 +8,7 @@ char _license[] SEC("license") = "GPL"; __u32 _version SEC("version") = 1; -#ifndef PAGE_SIZE -#define PAGE_SIZE 4096 -#endif +int page_size; /* userspace should set it */ #ifndef SOL_TCP #define SOL_TCP IPPROTO_TCP@@ -90,7 +88,7 @@ int _getsockopt(struct bpf_sockopt *ctx) * program can only see the first PAGE_SIZE * bytes of data. */ - if (optval_end - optval != PAGE_SIZE) + if (optval_end - optval != page_size) return 0; /* EPERM, unexpected data size */ return 1;@@ -161,7 +159,7 @@ int _setsockopt(struct bpf_sockopt *ctx) if (ctx->level == SOL_IP && ctx->optname == IP_FREEBIND) { /* Original optlen is larger than PAGE_SIZE. */ - if (ctx->optlen != PAGE_SIZE * 2) + if (ctx->optlen != page_size * 2) return 0; /* EPERM, unexpected data size */ if (optval + 1 > optval_end)@@ -175,7 +173,7 @@ int _setsockopt(struct bpf_sockopt *ctx) * program can only see the first PAGE_SIZE * bytes of data. */ - if (optval_end - optval != PAGE_SIZE) + if (optval_end - optval != page_size) return 0; /* EPERM, unexpected data size */ return 1; --2.29.2