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Thu, 12 Mar 2026 23:18:42 -0700 (PDT) X-Received: by 2002:a05:6a20:cc0b:b0:398:b61e:ff49 with SMTP id adf61e73a8af0-398ecd396b6mr1762951637.49.1773382721627; Thu, 12 Mar 2026 23:18:41 -0700 (PDT) Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: In-Reply-To: From: Jason Wang Date: Fri, 13 Mar 2026 14:18:30 +0800 X-Gm-Features: AaiRm50ufnhualN_GPqqA8VArNbrVUugmk7--xHwxcWqjvMX3sr4KWxvuUQv5M0 Message-ID: Subject: Re: [PATCH] virtio: document the map API in the driver writing guide To: John S Cc: mst@redhat.com, xuanzhuo@linux.alibaba.com, eperezma@redhat.com, corbet@lwn.net, skhan@linuxfoundation.org, virtualization@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: dKF61BP-Ygvlsd3o8s2enTgBrbNx5CUx-8HWZDop6eg_1773382722 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, Mar 13, 2026 at 5:58=E2=80=AFAM John S wrote: > > Add a new "Buffer mapping" section to the virtio driver writing guide > documenting the virtio map API (struct virtio_map_ops). This API was > introduced in commit bee8c7c24b73 ("virtio: introduce map ops in virtio > core") to allow transports and devices that do not perform DMA (such > as VDUSE) to provide their own buffer mapping logic instead of abusing > the DMA API. > > The new section explains when and why custom map ops are used, documents > the virtio_map_ops structure and the union virtio_map token, and > references the driver-facing mapping helpers with their kernel-doc. > > Signed-off-by: Kit Dallege > --- Acked-by: Jason Wang Thanks