Received-SPF: pass (google.com: domain of linux-kernel+bounces-63583-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249;
Message-ID: <94ff0733-5987-4bf5-a53c-011e03aa6323@gmail.com>
Date: Tue, 13 Feb 2024 13:15:08 +0000
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [RFC PATCH net-next v5 05/14] netdev: netdevice devmem allocator
Content-Language: en-US
To: Mina Almasry <almasrymina@google.com>,
 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
 Martin KaFai Lau <martin.lau@linux.dev>, Song Liu <song@kernel.org>,
 Yonghong Song <yonghong.song@linux.dev>,
 John Fastabend <john.fastabend@gmail.com>, KP Singh <kpsingh@kernel.org>,
 Stanislav Fomichev <sdf@google.com>, Hao Luo <haoluo@google.com>,
 Jiri Olsa <jolsa@kernel.org>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
 linux-alpha@vger.kernel.org, linux-mips@vger.kernel.org,
 linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org,
 linux-trace-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
 bpf@vger.kernel.org, linux-kselftest@vger.kernel.org,
 linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org
Cc: "David S. Miller" <davem@davemloft.net>,
 Eric Dumazet <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>,
 Paolo Abeni <pabeni@redhat.com>, Jonathan Corbet <corbet@lwn.net>,
 Richard Henderson <richard.henderson@linaro.org>,
 Ivan Kokshaysky <ink@jurassic.park.msu.ru>, Matt Turner
 <mattst88@gmail.com>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
 "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>,
 Helge Deller <deller@gmx.de>, Jesper Dangaard Brouer <hawk@kernel.org>,
 Ilias Apalodimas <ilias.apalodimas@linaro.org>,
 Steven Rostedt <rostedt@goodmis.org>, Masami Hiramatsu
 <mhiramat@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
 Alexei Starovoitov <ast@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>,
 Andrii Nakryiko <andrii@kernel.org>, David Ahern <dsahern@kernel.org>,
 Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
 Shuah Khan <shuah@kernel.org>, Sumit Semwal <sumit.semwal@linaro.org>,
 =?UTF-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>,
 David Wei <dw@davidwei.uk>, Jason Gunthorpe <jgg@ziepe.ca>,
 Yunsheng Lin <linyunsheng@huawei.com>, Shailend Chand <shailend@google.com>,
 Harshitha Ramamurthy <hramamurthy@google.com>,
 Shakeel Butt <shakeelb@google.com>, Jeroen de Borst <jeroendb@google.com>,
 Praveen Kaligineedi <pkaligineedi@google.com>,
 Willem de Bruijn <willemb@google.com>, Kaiyuan Zhang <kaiyuanz@google.com>
References: <20231218024024.3516870-1-almasrymina@google.com>
 <20231218024024.3516870-6-almasrymina@google.com>
From: Pavel Begunkov <asml.silence@gmail.com>
In-Reply-To: <20231218024024.3516870-6-almasrymina@google.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

On 12/18/23 02:40, Mina Almasry wrote:
> Implement netdev devmem allocator. The allocator takes a given struct
> netdev_dmabuf_binding as input and allocates net_iov from that
> binding.
> 
> The allocation simply delegates to the binding's genpool for the
> allocation logic and wraps the returned memory region in a net_iov
> struct.
> 
> Signed-off-by: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com>
> Signed-off-by: Mina Almasry <almasrymina@google.com>
> 
> ---
> 
> v1:
> - Rename devmem -> dmabuf (David).
> 
> ---
>   include/net/devmem.h | 12 ++++++++++++
>   include/net/netmem.h | 26 ++++++++++++++++++++++++++
>   net/core/dev.c       | 38 ++++++++++++++++++++++++++++++++++++++
>   3 files changed, 76 insertions(+)
> 
..
> diff --git a/include/net/netmem.h b/include/net/netmem.h
> index 45eb42d9990b..7fce2efc8707 100644
> --- a/include/net/netmem.h
> +++ b/include/net/netmem.h
> @@ -14,8 +14,34 @@
>   
>   struct net_iov {
>   	struct dmabuf_genpool_chunk_owner *owner;
> +	unsigned long dma_addr;
>   };
>   
> +static inline struct dmabuf_genpool_chunk_owner *
> +net_iov_owner(const struct net_iov *niov)
> +{
> +	return niov->owner;
> +}
> +
> +static inline unsigned int net_iov_idx(const struct net_iov *niov)
> +{
> +	return niov - net_iov_owner(niov)->niovs;
> +}
> +
> +static inline dma_addr_t net_iov_dma_addr(const struct net_iov *niov)
> +{
> +	struct dmabuf_genpool_chunk_owner *owner = net_iov_owner(niov);
> +
> +	return owner->base_dma_addr +
> +	       ((dma_addr_t)net_iov_idx(niov) << PAGE_SHIFT);

Looks like it should have been niov->dma_addr

> +}
> +
> +static inline struct netdev_dmabuf_binding *
> +net_iov_binding(const struct net_iov *niov)
> +{
> +	return net_iov_owner(niov)->binding;
> +}
> +
>   /* netmem */
>   
>   struct netmem {
..

-- 
Pavel Begunkov