Re: [PATCH v12 2/4] uacce: add uacce driver

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Wed, Jan 15, 2020 at 10:12:46PM +0800, Zhangfei Gao wrote:
> From: Kenneth Lee <liguozhu@hisilicon.com>
> 
> Uacce (Unified/User-space-access-intended Accelerator Framework) targets to
> provide Shared Virtual Addressing (SVA) between accelerators and processes.
> So accelerator can access any data structure of the main cpu.
> This differs from the data sharing between cpu and io device, which share
> only data content rather than address.
> Since unified address, hardware and user space of process can share the
> same virtual address in the communication.
> 
> Uacce create a chrdev for every registration, the queue is allocated to
> the process when the chrdev is opened. Then the process can access the
> hardware resource by interact with the queue file. By mmap the queue
> file space to user space, the process can directly put requests to the
> hardware without syscall to the kernel space.
> 
> The IOMMU core only tracks mm<->device bonds at the moment, because it
> only needs to handle IOTLB invalidation and PASID table entries. However
> uacce needs a finer granularity since multiple queues from the same
> device can be bound to an mm. When the mm exits, all bound queues must
> be stopped so that the IOMMU can safely clear the PASID table entry and
> reallocate the PASID.
> 
> An intermediate struct uacce_mm links uacce devices and queues.
> Note that an mm may be bound to multiple devices but an uacce_mm
> structure only ever belongs to a single device, because we don't need
> anything more complex (if multiple devices are bound to one mm, then
> we'll create one uacce_mm for each bond).
> 
>         uacce_device --+-- uacce_mm --+-- uacce_queue
>                        |              '-- uacce_queue
>                        |
>                        '-- uacce_mm --+-- uacce_queue
>                                       +-- uacce_queue
>                                       '-- uacce_queue
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Kenneth Lee <liguozhu@hisilicon.com>
> Signed-off-by: Zaibo Xu <xuzaibo@huawei.com>
> Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>

Looks much saner now, thanks for all of the work on this:

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Or am I supposed to take this in my tree?  If so, I can, but I need an
ack for the crypto parts.

thanks,

greg k-h