[bpf-next,v3,10/16] bpf: Export bpf_dynptr_set_size

Commit Message

Hou Tao March 27, 2025, 8:34 a.m. UTC

From: Hou Tao <[e-mail]>

It will be used by the following patch to shrink the size of dynptr when
the actual data length is smaller than the size of dynptr during
map_get_next_key operation.

Signed-off-by: Hou Tao <[e-mail]>
---
 include/linux/bpf.h  | 1 +
 kernel/bpf/helpers.c | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

Patch

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 737890e5c58b4..4f4b43b68f8d1 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1361,6 +1361,7 @@  enum bpf_dynptr_type {
 };
 
 int bpf_dynptr_check_size(u32 size);
+void bpf_dynptr_set_size(struct bpf_dynptr_kern *ptr, u32 new_size);
 u32 __bpf_dynptr_size(const struct bpf_dynptr_kern *ptr);
 const void *__bpf_dynptr_data(const struct bpf_dynptr_kern *ptr, u32 len);
 void *__bpf_dynptr_data_rw(const struct bpf_dynptr_kern *ptr, u32 len);
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index ddaa41a70676c..67c13a6d20dae 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -1688,7 +1688,7 @@  u32 __bpf_dynptr_size(const struct bpf_dynptr_kern *ptr)
 	return ptr->size & DYNPTR_SIZE_MASK;
 }
 
-static void bpf_dynptr_set_size(struct bpf_dynptr_kern *ptr, u32 new_size)
+void bpf_dynptr_set_size(struct bpf_dynptr_kern *ptr, u32 new_size)
 {
 	u32 metadata = ptr->size & ~DYNPTR_SIZE_MASK;