Now that there are helpers for converting IP tunnel flags between the old __be16 format and the bitmap format, make sure they work as expected by adding a couple of tests to the bitmap testing suite. The helpers are all inline, so no dependencies on the related CONFIG_* (or a standalone module) are needed. Cover three possible cases: 1. No bits past BIT(15) are set, VTI/SIT bits are not set. This conversion is almost a direct assignment. 2. No bits past BIT(15) are set, but VTI/SIT bit is set. During the conversion, it must be transformed into BIT(16) in the bitmap, but still compatible with the __be16 format. 3. The bitmap has bits past BIT(15) set (not the VTI/SIT one). The result will be truncated. Note that currently __IP_TUNNEL_FLAG_NUM is 17 (incl. special), which means that the result of this case is currently semi-false-positive. When BIT(17) is finally here, it will be adjusted accordingly. Signed-off-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx> --- lib/test_bitmap.c | 105 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c index a005fcd70ed7..2981277ed8d4 100644 --- a/lib/test_bitmap.c +++ b/lib/test_bitmap.c @@ -14,6 +14,8 @@ #include <linux/string.h> #include <linux/uaccess.h> +#include <net/ip_tunnels.h> + #include "../tools/testing/selftests/kselftest_module.h" #define EXP1_IN_BITS (sizeof(exp1) * 8) @@ -1387,6 +1389,108 @@ static void __init test_bitmap_write_perf(void) #undef TEST_BIT_LEN +struct ip_tunnel_flags_test { + const u16 *src_bits; + const u16 *exp_bits; + u8 src_num; + u8 exp_num; + __be16 exp_val; + bool exp_comp:1; +}; + +#define IP_TUNNEL_FLAGS_TEST(src, comp, eval, exp) { \ + .src_bits = (src), \ + .src_num = ARRAY_SIZE(src), \ + .exp_comp = (comp), \ + .exp_val = (eval), \ + .exp_bits = (exp), \ + .exp_num = ARRAY_SIZE(exp), \ +} + +/* These are __be16-compatible and can be compared as is */ +static const u16 ip_tunnel_flags_1[] __initconst = { + IP_TUNNEL_KEY_BIT, + IP_TUNNEL_STRICT_BIT, + IP_TUNNEL_ERSPAN_OPT_BIT, +}; + +/* + * Due to the previous flags design limitation, setting either + * ``IP_TUNNEL_CSUM_BIT`` (on Big Endian) or ``IP_TUNNEL_DONT_FRAGMENT_BIT`` + * (on Little) also sets VTI/ISATAP bit. In the bitmap implementation, they + * correspond to ``BIT(16)``, which is bigger than ``U16_MAX``, but still is + * backward-compatible. + */ +#ifdef __BIG_ENDIAN +#define IP_TUNNEL_CONFLICT_BIT IP_TUNNEL_CSUM_BIT +#else +#define IP_TUNNEL_CONFLICT_BIT IP_TUNNEL_DONT_FRAGMENT_BIT +#endif + +static const u16 ip_tunnel_flags_2_src[] __initconst = { + IP_TUNNEL_CONFLICT_BIT, +}; + +static const u16 ip_tunnel_flags_2_exp[] __initconst = { + IP_TUNNEL_CONFLICT_BIT, + IP_TUNNEL_SIT_ISATAP_BIT, +}; + +/* Bits 17 and higher are not compatible with __be16 flags */ +static const u16 ip_tunnel_flags_3_src[] __initconst = { + IP_TUNNEL_VXLAN_OPT_BIT, + 17, + 18, + 20, +}; + +static const u16 ip_tunnel_flags_3_exp[] __initconst = { + IP_TUNNEL_VXLAN_OPT_BIT, +}; + +static const struct ip_tunnel_flags_test ip_tunnel_flags_test[] __initconst = { + IP_TUNNEL_FLAGS_TEST(ip_tunnel_flags_1, true, + cpu_to_be16(BIT(IP_TUNNEL_KEY_BIT) | + BIT(IP_TUNNEL_STRICT_BIT) | + BIT(IP_TUNNEL_ERSPAN_OPT_BIT)), + ip_tunnel_flags_1), + IP_TUNNEL_FLAGS_TEST(ip_tunnel_flags_2_src, true, VTI_ISVTI, + ip_tunnel_flags_2_exp), + IP_TUNNEL_FLAGS_TEST(ip_tunnel_flags_3_src, + /* + * This must be set to ``false`` once + * ``__IP_TUNNEL_FLAG_NUM`` goes above 17. + */ + true, + cpu_to_be16(BIT(IP_TUNNEL_VXLAN_OPT_BIT)), + ip_tunnel_flags_3_exp), +}; + +static void __init test_ip_tunnel_flags(void) +{ + for (u32 i = 0; i < ARRAY_SIZE(ip_tunnel_flags_test); i++) { + typeof(*ip_tunnel_flags_test) *test = &ip_tunnel_flags_test[i]; + IP_TUNNEL_DECLARE_FLAGS(src) = { }; + IP_TUNNEL_DECLARE_FLAGS(exp) = { }; + IP_TUNNEL_DECLARE_FLAGS(out); + + for (u32 j = 0; j < test->src_num; j++) + __set_bit(test->src_bits[j], src); + + for (u32 j = 0; j < test->exp_num; j++) + __set_bit(test->exp_bits[j], exp); + + ip_tunnel_flags_from_be16(out, test->exp_val); + + expect_eq_uint(test->exp_comp, + ip_tunnel_flags_is_be16_compat(src)); + expect_eq_uint((__force u16)test->exp_val, + (__force u16)ip_tunnel_flags_to_be16(src)); + + __ipt_flag_op(expect_eq_bitmap, exp, out); + } +} + static void __init selftest(void) { test_zero_clear(); @@ -1405,6 +1509,7 @@ static void __init selftest(void) test_bitmap_read_write(); test_bitmap_read_perf(); test_bitmap_write_perf(); + test_ip_tunnel_flags(); test_find_nth_bit(); test_for_each_set_bit(); -- 2.41.0