Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210912165309.98695-1-ogabbay@kernel.org> <20210912165309.98695-2-ogabbay@kernel.org>
 <20210928171329.GF3544071@ziepe.ca>
In-Reply-To: <20210928171329.GF3544071@ziepe.ca>
From:   Oded Gabbay <ogabbay@kernel.org>
Date:   Tue, 28 Sep 2021 22:12:45 +0300
Message-ID: <CAFCwf11_2TTVnqr8HqrsCW6cxUHu9txKuX-3U6mgMVPq8WqKdg@mail.gmail.com>
Subject: Re: [PATCH v6 1/2] habanalabs: define uAPI to export FD for DMA-BUF
To:     Jason Gunthorpe <jgg@ziepe.ca>
Cc:     "Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        =?UTF-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        Gal Pressman <galpress@amazon.com>,
        Yossi Leybovich <sleybo@amazon.com>,
        Maling list - DRI developers 
        <dri-devel@lists.freedesktop.org>,
        linux-rdma <linux-rdma@vger.kernel.org>,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        Doug Ledford <dledford@redhat.com>,
        Dave Airlie <airlied@gmail.com>,
        Alex Deucher <alexander.deucher@amd.com>,
        Leon Romanovsky <leonro@nvidia.com>,
        Christoph Hellwig <hch@lst.de>,
        amd-gfx list <amd-gfx@lists.freedesktop.org>,
        "moderated list:DMA BUFFER SHARING FRAMEWORK" 
        <linaro-mm-sig@lists.linaro.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue, Sep 28, 2021 at 8:13 PM Jason Gunthorpe <jgg@ziepe.ca> wrote:
>
> On Sun, Sep 12, 2021 at 07:53:08PM +0300, Oded Gabbay wrote:
> >       /* HL_MEM_OP_* */
> >       __u32 op;
> > -     /* HL_MEM_* flags */
> > +     /* HL_MEM_* flags.
> > +      * For the HL_MEM_OP_EXPORT_DMABUF_FD opcode, this field holds the
> > +      * DMA-BUF file/FD flags.
> > +      */
> >       __u32 flags;
> >       /* Context ID - Currently not in use */
> >       __u32 ctx_id;
> > @@ -1072,6 +1091,13 @@ struct hl_mem_out {
> >
> >                       __u32 pad;
> >               };
> > +
> > +             /* Returned in HL_MEM_OP_EXPORT_DMABUF_FD. Represents the
> > +              * DMA-BUF object that was created to describe a memory
> > +              * allocation on the device's memory space. The FD should be
> > +              * passed to the importer driver
> > +              */
> > +             __u64 fd;
>
> fd's should be a s32 type in a fixed width uapi.
Yep, will correct this.

>
> I usually expect to see the uapi changes inside the commit that
> consumes them, splitting the patch like this seems strange but
> harmless.
I'll remember that when I send the RDMA patches down the road :)

Thanks,
Oded
>
> Jason