diff mbox series

[RFC,bpf-next,2/9] bpf: export btf functions for modules

Message ID 165643384372.449467.131935445575415818.stgit@firesoul (mailing list archive)
State RFC
Delegated to: BPF
Headers show
Series Introduce XDP-hints via BTF | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-VM_Test-3 success Logs for Kernel LATEST on z15 with gcc
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-1 success Logs for Kernel LATEST on ubuntu-latest with gcc
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Kernel LATEST on ubuntu-latest with llvm-15
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1427 this patch: 1427
netdev/cc_maintainers fail 12 maintainers not CCed: netdev@vger.kernel.org daniel@iogearbox.net songliubraving@fb.com ast@kernel.org hawk@kernel.org yhs@fb.com davem@davemloft.net john.fastabend@gmail.com kuba@kernel.org kafai@fb.com andrii@kernel.org kpsingh@kernel.org
netdev/build_clang success Errors and warnings before: 169 this patch: 169
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1434 this patch: 1434
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 45 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jesper Dangaard Brouer June 28, 2022, 4:30 p.m. UTC
This allows modules to lookup their own module BTF info.

These are get and set operations that bump the refcount.
Thus, modules can use this to control the lifetime.

Suggested-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
---
 include/linux/btf.h |    2 ++
 kernel/bpf/btf.c    |   13 ++++++++++++-
 2 files changed, 14 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/include/linux/btf.h b/include/linux/btf.h
index 1bfed7fa0428..df9776018059 100644
--- a/include/linux/btf.h
+++ b/include/linux/btf.h
@@ -126,6 +126,8 @@  u32 btf_obj_id(const struct btf *btf);
 bool btf_is_kernel(const struct btf *btf);
 bool btf_is_module(const struct btf *btf);
 struct module *btf_try_get_module(const struct btf *btf);
+struct btf *btf_get_module_btf(const struct module *module);
+void btf_put_module_btf(struct btf *btf);
 u32 btf_nr_types(const struct btf *btf);
 bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
 			   const struct btf_member *m,
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 2e2066d6af94..96fd5e469b42 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -534,6 +534,7 @@  s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind)
 
 	return -ENOENT;
 }
+EXPORT_SYMBOL_GPL(btf_find_by_name_kind);
 
 static s32 bpf_find_btf_id(const char *name, u32 kind, struct btf **btf_p)
 {
@@ -1674,6 +1675,15 @@  void btf_put(struct btf *btf)
 	}
 }
 
+void btf_put_module_btf(struct btf *btf)
+{
+	if (!btf_is_module(btf))
+		return;
+
+	btf_put(btf);
+}
+EXPORT_SYMBOL_GPL(btf_put_module_btf);
+
 static int env_resolve_init(struct btf_verifier_env *env)
 {
 	struct btf *btf = env->btf;
@@ -7022,7 +7032,7 @@  struct module *btf_try_get_module(const struct btf *btf)
 /* Returns struct btf corresponding to the struct module.
  * This function can return NULL or ERR_PTR.
  */
-static struct btf *btf_get_module_btf(const struct module *module)
+struct btf *btf_get_module_btf(const struct module *module)
 {
 #ifdef CONFIG_DEBUG_INFO_BTF_MODULES
 	struct btf_module *btf_mod, *tmp;
@@ -7051,6 +7061,7 @@  static struct btf *btf_get_module_btf(const struct module *module)
 
 	return btf;
 }
+EXPORT_SYMBOL_GPL(btf_get_module_btf);
 
 BPF_CALL_4(bpf_btf_find_by_name_kind, char *, name, int, name_sz, u32, kind, int, flags)
 {