From 263ae152e96253f40c2c276faad8629e096b3bad Mon Sep 17 00:00:00 2001 From: Joanne Koong Date: Mon, 23 May 2022 14:07:08 -0700 Subject: bpf: Add bpf_dynptr_from_mem for local dynptrs This patch adds a new api bpf_dynptr_from_mem: long bpf_dynptr_from_mem(void *data, u32 size, u64 flags, struct bpf_dynptr *ptr); which initializes a dynptr to point to a bpf program's local memory. For now only local memory that is of reg type PTR_TO_MAP_VALUE is supported. Signed-off-by: Joanne Koong Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220523210712.3641569-3-joannelkoong@gmail.com --- tools/include/uapi/linux/bpf.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 610944cb3389..9be3644457dd 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5178,6 +5178,17 @@ union bpf_attr { * Dynamically cast a *sk* pointer to a *mptcp_sock* pointer. * Return * *sk* if casting is valid, or **NULL** otherwise. + * + * long bpf_dynptr_from_mem(void *data, u32 size, u64 flags, struct bpf_dynptr *ptr) + * Description + * Get a dynptr to local memory *data*. + * + * *data* must be a ptr to a map value. + * The maximum *size* supported is DYNPTR_MAX_SIZE. + * *flags* is currently unused. + * Return + * 0 on success, -E2BIG if the size exceeds DYNPTR_MAX_SIZE, + * -EINVAL if flags is not 0. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5377,6 +5388,7 @@ union bpf_attr { FN(kptr_xchg), \ FN(map_lookup_percpu_elem), \ FN(skc_to_mptcp_sock), \ + FN(dynptr_from_mem), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper -- cgit v1.2.3-59-g8ed1b