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References: <20220614115420.1964686-1-roberto.sassu@huawei.com> <20220614115420.1964686-2-roberto.sassu@huawei.com>
In-Reply-To: <20220614115420.1964686-2-roberto.sassu@huawei.com>
From:   Joanne Koong <joannelkoong@gmail.com>
Date:   Tue, 14 Jun 2022 10:50:42 -0700
Message-ID: <CAJnrk1bz33yeRRXP46tU1iKOHKxowj5-BaThT24kEnfUP9aAeQ@mail.gmail.com>
Subject: Re: [PATCH v4 1/4] bpf: Export bpf_dynptr_get_size()
To:     Roberto Sassu <roberto.sassu@huawei.com>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        KP Singh <kpsingh@kernel.org>,
        John Fastabend <john.fastabend@gmail.com>,
        bpf <bpf@vger.kernel.org>, netdev <netdev@vger.kernel.org>,
        linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org
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On Tue, Jun 14, 2022 at 4:54 AM Roberto Sassu <roberto.sassu@huawei.com> wrote:
>
> Export bpf_dynptr_get_size(), so that kernel code dealing with eBPF dynamic
> pointers can obtain the real size of data carried by this data structure.
>
> Cc: Joanne Koong <joannelkoong@gmail.com>
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>

LGTM

Acked-by: Joanne Koong <joannelkoong@gmail.com>

> ---
>  include/linux/bpf.h  | 1 +
>  kernel/bpf/helpers.c | 2 +-
>  2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index 8e6092d0ea95..6eb03a0c9687 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -2420,5 +2420,6 @@ void bpf_dynptr_init(struct bpf_dynptr_kern *ptr, void *data,
>                      enum bpf_dynptr_type type, u32 offset, u32 size);
>  void bpf_dynptr_set_null(struct bpf_dynptr_kern *ptr);
>  int bpf_dynptr_check_size(u32 size);
> +u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr);
>
>  #endif /* _LINUX_BPF_H */
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index 225806a02efb..29e1810afaf6 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -1430,7 +1430,7 @@ static void bpf_dynptr_set_type(struct bpf_dynptr_kern *ptr, enum bpf_dynptr_typ
>         ptr->size |= type << DYNPTR_TYPE_SHIFT;
>  }
>
> -static u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr)
> +u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr)
>  {
>         return ptr->size & DYNPTR_SIZE_MASK;
>  }
> --
> 2.25.1
>