From: Ilya Leoshkevich <iii@linux.ibm.com>
To: Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Andrii Nakryiko <andrii@kernel.org>, Yonghong Song <yhs@fb.com>,
Arnaldo Carvalho de Melo <acme@redhat.com>,
John Fastabend <john.fastabend@gmail.com>
Cc: bpf@vger.kernel.org, Heiko Carstens <heiko.carstens@de.ibm.com>,
Vasily Gorbik <gor@linux.ibm.com>,
Ilya Leoshkevich <iii@linux.ibm.com>
Subject: [PATCH v3 bpf-next 4/6] bpf: Add BTF_KIND_FLOAT support
Date: Sat, 20 Feb 2021 04:49:57 +0100 [thread overview]
Message-ID: <20210220034959.27006-5-iii@linux.ibm.com> (raw)
In-Reply-To: <20210220034959.27006-1-iii@linux.ibm.com>
On the kernel side, introduce a new btf_kind_operations. It is
similar to that of BTF_KIND_INT, however, it does not need to
handle encodings and bit offsets. Do not implement printing, since
the kernel does not know how to format floating-point values.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
kernel/bpf/btf.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 75 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 2efeb5f4b343..813c2bfe284f 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -173,7 +173,7 @@
#define BITS_ROUNDUP_BYTES(bits) \
(BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits))
-#define BTF_INFO_MASK 0x8f00ffff
+#define BTF_INFO_MASK 0x9f00ffff
#define BTF_INT_MASK 0x0fffffff
#define BTF_TYPE_ID_VALID(type_id) ((type_id) <= BTF_MAX_TYPE)
#define BTF_STR_OFFSET_VALID(name_off) ((name_off) <= BTF_MAX_NAME_OFFSET)
@@ -280,6 +280,7 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = {
[BTF_KIND_FUNC_PROTO] = "FUNC_PROTO",
[BTF_KIND_VAR] = "VAR",
[BTF_KIND_DATASEC] = "DATASEC",
+ [BTF_KIND_FLOAT] = "FLOAT",
};
static const char *btf_type_str(const struct btf_type *t)
@@ -574,6 +575,7 @@ static bool btf_type_has_size(const struct btf_type *t)
case BTF_KIND_UNION:
case BTF_KIND_ENUM:
case BTF_KIND_DATASEC:
+ case BTF_KIND_FLOAT:
return true;
}
@@ -1704,6 +1706,7 @@ __btf_resolve_size(const struct btf *btf, const struct btf_type *type,
case BTF_KIND_STRUCT:
case BTF_KIND_UNION:
case BTF_KIND_ENUM:
+ case BTF_KIND_FLOAT:
size = type->size;
goto resolved;
@@ -1849,7 +1852,7 @@ static int btf_df_check_kflag_member(struct btf_verifier_env *env,
return -EINVAL;
}
-/* Used for ptr, array and struct/union type members.
+/* Used for ptr, array struct/union and float type members.
* int, enum and modifier types have their specific callback functions.
*/
static int btf_generic_check_kflag_member(struct btf_verifier_env *env,
@@ -3675,6 +3678,75 @@ static const struct btf_kind_operations datasec_ops = {
.show = btf_datasec_show,
};
+static s32 btf_float_check_meta(struct btf_verifier_env *env,
+ const struct btf_type *t,
+ u32 meta_left)
+{
+ if (btf_type_vlen(t)) {
+ btf_verifier_log_type(env, t, "vlen != 0");
+ return -EINVAL;
+ }
+
+ if (btf_type_kflag(t)) {
+ btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
+ return -EINVAL;
+ }
+
+ if (t->size != 2 && t->size != 4 && t->size != 8 && t->size != 12 &&
+ t->size != 16) {
+ btf_verifier_log_type(env, t, "Invalid type_size");
+ return -EINVAL;
+ }
+
+ btf_verifier_log_type(env, t, NULL);
+
+ return 0;
+}
+
+static int btf_float_check_member(struct btf_verifier_env *env,
+ const struct btf_type *struct_type,
+ const struct btf_member *member,
+ const struct btf_type *member_type)
+{
+ u64 start_offset_bytes;
+ u64 end_offset_bytes;
+ u64 align_bytes;
+ u64 align_bits;
+
+ align_bytes = min_t(u64, sizeof(void *), member_type->size);
+ align_bits = align_bytes * BITS_PER_BYTE;
+ if (member->offset % align_bits) {
+ btf_verifier_log_member(env, struct_type, member,
+ "Member is not properly aligned");
+ return -EINVAL;
+ }
+
+ start_offset_bytes = member->offset / BITS_PER_BYTE;
+ end_offset_bytes = start_offset_bytes + member_type->size;
+ if (end_offset_bytes > struct_type->size) {
+ btf_verifier_log_member(env, struct_type, member,
+ "Member exceeds struct_size");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void btf_float_log(struct btf_verifier_env *env,
+ const struct btf_type *t)
+{
+ btf_verifier_log(env, "size=%u", t->size);
+}
+
+static const struct btf_kind_operations float_ops = {
+ .check_meta = btf_float_check_meta,
+ .resolve = btf_df_resolve,
+ .check_member = btf_float_check_member,
+ .check_kflag_member = btf_generic_check_kflag_member,
+ .log_details = btf_float_log,
+ .show = btf_df_show,
+};
+
static int btf_func_proto_check(struct btf_verifier_env *env,
const struct btf_type *t)
{
@@ -3808,6 +3880,7 @@ static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = {
[BTF_KIND_FUNC_PROTO] = &func_proto_ops,
[BTF_KIND_VAR] = &var_ops,
[BTF_KIND_DATASEC] = &datasec_ops,
+ [BTF_KIND_FLOAT] = &float_ops,
};
static s32 btf_check_meta(struct btf_verifier_env *env,
--
2.29.2
next prev parent reply other threads:[~2021-02-20 3:52 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-20 3:49 [PATCH v3 bpf-next 0/6] Add BTF_KIND_FLOAT support Ilya Leoshkevich
2021-02-20 3:49 ` [PATCH v3 bpf-next 1/6] bpf: Add BTF_KIND_FLOAT to uapi Ilya Leoshkevich
2021-02-22 3:42 ` Yonghong Song
2021-02-20 3:49 ` [PATCH v3 bpf-next 2/6] libbpf: Add BTF_KIND_FLOAT support Ilya Leoshkevich
2021-02-22 3:41 ` Yonghong Song
2021-02-20 3:49 ` [PATCH v3 bpf-next 3/6] tools/bpftool: " Ilya Leoshkevich
2021-02-22 3:44 ` Yonghong Song
2021-02-20 3:49 ` Ilya Leoshkevich [this message]
2021-02-20 6:13 ` [PATCH v3 bpf-next 4/6] bpf: " kernel test robot
2021-02-20 6:24 ` kernel test robot
2021-02-21 16:37 ` Ilya Leoshkevich
2021-02-20 3:49 ` [PATCH v3 bpf-next 5/6] selftest/bpf: Add BTF_KIND_FLOAT tests Ilya Leoshkevich
2021-02-22 3:53 ` Yonghong Song
2021-02-20 3:49 ` [PATCH v3 bpf-next 6/6] bpf: Document BTF_KIND_FLOAT in btf.rst Ilya Leoshkevich
2021-02-22 3:55 ` Yonghong Song
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210220034959.27006-5-iii@linux.ibm.com \
--to=iii@linux.ibm.com \
--cc=acme@redhat.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=gor@linux.ibm.com \
--cc=heiko.carstens@de.ibm.com \
--cc=john.fastabend@gmail.com \
--cc=yhs@fb.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).