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Diffstat (limited to 'kernel/bpf/btf.c')
-rw-r--r--kernel/bpf/btf.c163
1 files changed, 136 insertions, 27 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 715f9fcf4712..bd3921b1514b 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -157,7 +157,7 @@
*
*/
-#define BITS_PER_U64 (sizeof(u64) * BITS_PER_BYTE)
+#define BITS_PER_U128 (sizeof(u64) * BITS_PER_BYTE * 2)
#define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1)
#define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK)
#define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3)
@@ -355,6 +355,11 @@ static bool btf_type_is_struct(const struct btf_type *t)
return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
}
+static bool __btf_type_is_struct(const struct btf_type *t)
+{
+ return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT;
+}
+
static bool btf_type_is_array(const struct btf_type *t)
{
return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY;
@@ -467,7 +472,7 @@ static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t)
return kind_ops[BTF_INFO_KIND(t->info)];
}
-bool btf_name_offset_valid(const struct btf *btf, u32 offset)
+static bool btf_name_offset_valid(const struct btf *btf, u32 offset)
{
return BTF_STR_OFFSET_VALID(offset) &&
offset < btf->hdr.str_len;
@@ -525,7 +530,7 @@ const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id)
/*
* Regular int is not a bit field and it must be either
- * u8/u16/u32/u64.
+ * u8/u16/u32/u64 or __int128.
*/
static bool btf_type_int_is_regular(const struct btf_type *t)
{
@@ -538,7 +543,8 @@ static bool btf_type_int_is_regular(const struct btf_type *t)
if (BITS_PER_BYTE_MASKED(nr_bits) ||
BTF_INT_OFFSET(int_data) ||
(nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) &&
- nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64))) {
+ nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64) &&
+ nr_bytes != (2 * sizeof(u64)))) {
return false;
}
@@ -1063,9 +1069,9 @@ static int btf_int_check_member(struct btf_verifier_env *env,
nr_copy_bits = BTF_INT_BITS(int_data) +
BITS_PER_BYTE_MASKED(struct_bits_off);
- if (nr_copy_bits > BITS_PER_U64) {
+ if (nr_copy_bits > BITS_PER_U128) {
btf_verifier_log_member(env, struct_type, member,
- "nr_copy_bits exceeds 64");
+ "nr_copy_bits exceeds 128");
return -EINVAL;
}
@@ -1119,9 +1125,9 @@ static int btf_int_check_kflag_member(struct btf_verifier_env *env,
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
nr_copy_bits = nr_bits + BITS_PER_BYTE_MASKED(struct_bits_off);
- if (nr_copy_bits > BITS_PER_U64) {
+ if (nr_copy_bits > BITS_PER_U128) {
btf_verifier_log_member(env, struct_type, member,
- "nr_copy_bits exceeds 64");
+ "nr_copy_bits exceeds 128");
return -EINVAL;
}
@@ -1168,9 +1174,9 @@ static s32 btf_int_check_meta(struct btf_verifier_env *env,
nr_bits = BTF_INT_BITS(int_data) + BTF_INT_OFFSET(int_data);
- if (nr_bits > BITS_PER_U64) {
+ if (nr_bits > BITS_PER_U128) {
btf_verifier_log_type(env, t, "nr_bits exceeds %zu",
- BITS_PER_U64);
+ BITS_PER_U128);
return -EINVAL;
}
@@ -1211,33 +1217,93 @@ static void btf_int_log(struct btf_verifier_env *env,
btf_int_encoding_str(BTF_INT_ENCODING(int_data)));
}
+static void btf_int128_print(struct seq_file *m, void *data)
+{
+ /* data points to a __int128 number.
+ * Suppose
+ * int128_num = *(__int128 *)data;
+ * The below formulas shows what upper_num and lower_num represents:
+ * upper_num = int128_num >> 64;
+ * lower_num = int128_num & 0xffffffffFFFFFFFFULL;
+ */
+ u64 upper_num, lower_num;
+
+#ifdef __BIG_ENDIAN_BITFIELD
+ upper_num = *(u64 *)data;
+ lower_num = *(u64 *)(data + 8);
+#else
+ upper_num = *(u64 *)(data + 8);
+ lower_num = *(u64 *)data;
+#endif
+ if (upper_num == 0)
+ seq_printf(m, "0x%llx", lower_num);
+ else
+ seq_printf(m, "0x%llx%016llx", upper_num, lower_num);
+}
+
+static void btf_int128_shift(u64 *print_num, u16 left_shift_bits,
+ u16 right_shift_bits)
+{
+ u64 upper_num, lower_num;
+
+#ifdef __BIG_ENDIAN_BITFIELD
+ upper_num = print_num[0];
+ lower_num = print_num[1];
+#else
+ upper_num = print_num[1];
+ lower_num = print_num[0];
+#endif
+
+ /* shake out un-needed bits by shift/or operations */
+ if (left_shift_bits >= 64) {
+ upper_num = lower_num << (left_shift_bits - 64);
+ lower_num = 0;
+ } else {
+ upper_num = (upper_num << left_shift_bits) |
+ (lower_num >> (64 - left_shift_bits));
+ lower_num = lower_num << left_shift_bits;
+ }
+
+ if (right_shift_bits >= 64) {
+ lower_num = upper_num >> (right_shift_bits - 64);
+ upper_num = 0;
+ } else {
+ lower_num = (lower_num >> right_shift_bits) |
+ (upper_num << (64 - right_shift_bits));
+ upper_num = upper_num >> right_shift_bits;
+ }
+
+#ifdef __BIG_ENDIAN_BITFIELD
+ print_num[0] = upper_num;
+ print_num[1] = lower_num;
+#else
+ print_num[0] = lower_num;
+ print_num[1] = upper_num;
+#endif
+}
+
static void btf_bitfield_seq_show(void *data, u8 bits_offset,
u8 nr_bits, struct seq_file *m)
{
u16 left_shift_bits, right_shift_bits;
u8 nr_copy_bytes;
u8 nr_copy_bits;
- u64 print_num;
+ u64 print_num[2] = {};
- data += BITS_ROUNDDOWN_BYTES(bits_offset);
- bits_offset = BITS_PER_BYTE_MASKED(bits_offset);
nr_copy_bits = nr_bits + bits_offset;
nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits);
- print_num = 0;
- memcpy(&print_num, data, nr_copy_bytes);
+ memcpy(print_num, data, nr_copy_bytes);
#ifdef __BIG_ENDIAN_BITFIELD
left_shift_bits = bits_offset;
#else
- left_shift_bits = BITS_PER_U64 - nr_copy_bits;
+ left_shift_bits = BITS_PER_U128 - nr_copy_bits;
#endif
- right_shift_bits = BITS_PER_U64 - nr_bits;
-
- print_num <<= left_shift_bits;
- print_num >>= right_shift_bits;
+ right_shift_bits = BITS_PER_U128 - nr_bits;
- seq_printf(m, "0x%llx", print_num);
+ btf_int128_shift(print_num, left_shift_bits, right_shift_bits);
+ btf_int128_print(m, print_num);
}
@@ -1252,10 +1318,12 @@ static void btf_int_bits_seq_show(const struct btf *btf,
/*
* bits_offset is at most 7.
- * BTF_INT_OFFSET() cannot exceed 64 bits.
+ * BTF_INT_OFFSET() cannot exceed 128 bits.
*/
total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data);
- btf_bitfield_seq_show(data, total_bits_offset, nr_bits, m);
+ data += BITS_ROUNDDOWN_BYTES(total_bits_offset);
+ bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset);
+ btf_bitfield_seq_show(data, bits_offset, nr_bits, m);
}
static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t,
@@ -1274,6 +1342,9 @@ static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t,
}
switch (nr_bits) {
+ case 128:
+ btf_int128_print(m, data);
+ break;
case 64:
if (sign)
seq_printf(m, "%lld", *(s64 *)data);
@@ -1459,7 +1530,8 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
/* "typedef void new_void", "const void"...etc */
if (!btf_type_is_void(next_type) &&
- !btf_type_is_fwd(next_type)) {
+ !btf_type_is_fwd(next_type) &&
+ !btf_type_is_func_proto(next_type)) {
btf_verifier_log_type(env, v->t, "Invalid type_id");
return -EINVAL;
}
@@ -1979,6 +2051,43 @@ static void btf_struct_log(struct btf_verifier_env *env,
btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t));
}
+/* find 'struct bpf_spin_lock' in map value.
+ * return >= 0 offset if found
+ * and < 0 in case of error
+ */
+int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t)
+{
+ const struct btf_member *member;
+ u32 i, off = -ENOENT;
+
+ if (!__btf_type_is_struct(t))
+ return -EINVAL;
+
+ for_each_member(i, t, member) {
+ const struct btf_type *member_type = btf_type_by_id(btf,
+ member->type);
+ if (!__btf_type_is_struct(member_type))
+ continue;
+ if (member_type->size != sizeof(struct bpf_spin_lock))
+ continue;
+ if (strcmp(__btf_name_by_offset(btf, member_type->name_off),
+ "bpf_spin_lock"))
+ continue;
+ if (off != -ENOENT)
+ /* only one 'struct bpf_spin_lock' is allowed */
+ return -E2BIG;
+ off = btf_member_bit_offset(t, member);
+ if (off % 8)
+ /* valid C code cannot generate such BTF */
+ return -EINVAL;
+ off /= 8;
+ if (off % __alignof__(struct bpf_spin_lock))
+ /* valid struct bpf_spin_lock will be 4 byte aligned */
+ return -EINVAL;
+ }
+ return off;
+}
+
static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t,
u32 type_id, void *data, u8 bits_offset,
struct seq_file *m)
@@ -2001,12 +2110,12 @@ static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t,
member_offset = btf_member_bit_offset(t, member);
bitfield_size = btf_member_bitfield_size(t, member);
+ bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset);
+ bits8_offset = BITS_PER_BYTE_MASKED(member_offset);
if (bitfield_size) {
- btf_bitfield_seq_show(data, member_offset,
+ btf_bitfield_seq_show(data + bytes_offset, bits8_offset,
bitfield_size, m);
} else {
- bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset);
- bits8_offset = BITS_PER_BYTE_MASKED(member_offset);
ops = btf_type_ops(member_type);
ops->seq_show(btf, member_type, member->type,
data + bytes_offset, bits8_offset, m);