From 2654268c7989299f3dd623b0715279554336687c Mon Sep 17 00:00:00 2001 From: Alan Maguire Date: Mon, 28 Sep 2020 12:31:09 +0100 Subject: [PATCH] bpf: Add bpf_seq_printf_btf helper A helper is added to allow seq file writing of kernel data structures using vmlinux BTF. Its signature is long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr, u32 btf_ptr_size, u64 flags); Flags and struct btf_ptr definitions/use are identical to the bpf_snprintf_btf helper, and the helper returns 0 on success or a negative error value. Suggested-by: Alexei Starovoitov Signed-off-by: Alan Maguire Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/1601292670-1616-8-git-send-email-alan.maguire@oracle.com --- include/uapi/linux/bpf.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index cca9eb1..96ddb00 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3630,6 +3630,14 @@ union bpf_attr { * The number of bytes that were written (or would have been * written if output had to be truncated due to string size), * or a negative error in cases of failure. + * + * long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr, u32 ptr_size, u64 flags) + * Description + * Use BTF to write to seq_write a string representation of + * *ptr*->ptr, using *ptr*->type_id as per bpf_snprintf_btf(). + * *flags* are identical to those used for bpf_snprintf_btf. + * Return + * 0 on success or a negative error in case of failure. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -3782,6 +3790,7 @@ union bpf_attr { FN(d_path), \ FN(copy_from_user), \ FN(snprintf_btf), \ + FN(seq_printf_btf), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper