From ffa0c1cf59596fba54546ea828305acfcc2cf55e Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Sat, 15 Dec 2018 22:13:52 -0800 Subject: bpf: enable cgroup local storage map pretty print with kind_flag Commit 970289fc0a83 ("bpf: add bpffs pretty print for cgroup local storage maps") added bpffs pretty print for cgroup local storage maps. The commit worked for struct without kind_flag set. This patch refactored and made pretty print also work with kind_flag set for the struct. Acked-by: Martin KaFai Lau Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann --- kernel/bpf/btf.c | 37 ++++++++++++++++++++++++++++--------- kernel/bpf/local_storage.c | 17 ++++------------- 2 files changed, 32 insertions(+), 22 deletions(-) (limited to 'kernel') diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 93b6905e3a9b..e804b26a0506 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -546,22 +546,41 @@ static bool btf_type_int_is_regular(const struct btf_type *t) } /* - * Check that given type is a regular int and has the expected size. + * Check that given struct member is a regular int with expected + * offset and size. */ -bool btf_type_is_reg_int(const struct btf_type *t, u32 expected_size) +bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s, + const struct btf_member *m, + u32 expected_offset, u32 expected_size) { - u8 nr_bits, nr_bytes; - u32 int_data; + const struct btf_type *t; + u32 id, int_data; + u8 nr_bits; - if (!btf_type_is_int(t)) + id = m->type; + t = btf_type_id_size(btf, &id, NULL); + if (!t || !btf_type_is_int(t)) return false; int_data = btf_type_int(t); nr_bits = BTF_INT_BITS(int_data); - nr_bytes = BITS_ROUNDUP_BYTES(nr_bits); - if (BITS_PER_BYTE_MASKED(nr_bits) || - BTF_INT_OFFSET(int_data) || - nr_bytes != expected_size) + if (btf_type_kflag(s)) { + u32 bitfield_size = BTF_MEMBER_BITFIELD_SIZE(m->offset); + u32 bit_offset = BTF_MEMBER_BIT_OFFSET(m->offset); + + /* if kflag set, int should be a regular int and + * bit offset should be at byte boundary. + */ + return !bitfield_size && + BITS_ROUNDUP_BYTES(bit_offset) == expected_offset && + BITS_ROUNDUP_BYTES(nr_bits) == expected_size; + } + + if (BTF_INT_OFFSET(int_data) || + BITS_PER_BYTE_MASKED(m->offset) || + BITS_ROUNDUP_BYTES(m->offset) != expected_offset || + BITS_PER_BYTE_MASKED(nr_bits) || + BITS_ROUNDUP_BYTES(nr_bits) != expected_size) return false; return true; diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c index 5eca03da0989..07a34ef562a0 100644 --- a/kernel/bpf/local_storage.c +++ b/kernel/bpf/local_storage.c @@ -315,9 +315,8 @@ static int cgroup_storage_check_btf(const struct bpf_map *map, const struct btf_type *key_type, const struct btf_type *value_type) { - const struct btf_type *t; struct btf_member *m; - u32 id, size; + u32 offset, size; /* Key is expected to be of struct bpf_cgroup_storage_key type, * which is: @@ -338,25 +337,17 @@ static int cgroup_storage_check_btf(const struct bpf_map *map, * The first field must be a 64 bit integer at 0 offset. */ m = (struct btf_member *)(key_type + 1); - if (m->offset) - return -EINVAL; - id = m->type; - t = btf_type_id_size(btf, &id, NULL); size = FIELD_SIZEOF(struct bpf_cgroup_storage_key, cgroup_inode_id); - if (!t || !btf_type_is_reg_int(t, size)) + if (!btf_member_is_reg_int(btf, key_type, m, 0, size)) return -EINVAL; /* * The second field must be a 32 bit integer at 64 bit offset. */ m++; - if (m->offset != offsetof(struct bpf_cgroup_storage_key, attach_type) * - BITS_PER_BYTE) - return -EINVAL; - id = m->type; - t = btf_type_id_size(btf, &id, NULL); + offset = offsetof(struct bpf_cgroup_storage_key, attach_type); size = FIELD_SIZEOF(struct bpf_cgroup_storage_key, attach_type); - if (!t || !btf_type_is_reg_int(t, size)) + if (!btf_member_is_reg_int(btf, key_type, m, offset, size)) return -EINVAL; return 0; -- cgit v1.2.3-58-ga151