Re: [PATCH] xen: introduce xen_vring_use_dma

2020-07-15 Thread Stefano Stabellini
On Sat, 11 Jul 2020, Michael S. Tsirkin wrote: > On Fri, Jul 10, 2020 at 10:23:22AM -0700, Stefano Stabellini wrote: > > Sorry for the late reply -- a couple of conferences kept me busy. > > > > > > On Wed, 1 Jul 2020, Michael S. Tsirkin wrote: > > > On Wed, Jul 01, 2020 at 10:34:53AM -0700,

RE: [PATCH] xen: introduce xen_vring_use_dma

2020-07-12 Thread Peng Fan
> Subject: Re: [PATCH] xen: introduce xen_vring_use_dma > > Sorry for the late reply -- a couple of conferences kept me busy. > > > On Wed, 1 Jul 2020, Michael S. Tsirkin wrote: > > On Wed, Jul 01, 2020 at 10:34:53AM -0700, Stefano Stabellini wrote: > > >

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-07-11 Thread Michael S. Tsirkin
On Fri, Jul 10, 2020 at 10:23:22AM -0700, Stefano Stabellini wrote: > Sorry for the late reply -- a couple of conferences kept me busy. > > > On Wed, 1 Jul 2020, Michael S. Tsirkin wrote: > > On Wed, Jul 01, 2020 at 10:34:53AM -0700, Stefano Stabellini wrote: > > > Would you be in favor of a

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-07-10 Thread Stefano Stabellini
Sorry for the late reply -- a couple of conferences kept me busy. On Wed, 1 Jul 2020, Michael S. Tsirkin wrote: > On Wed, Jul 01, 2020 at 10:34:53AM -0700, Stefano Stabellini wrote: > > Would you be in favor of a more flexible check along the lines of the > > one proposed in the patch that

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-07-01 Thread Michael S. Tsirkin
On Wed, Jul 01, 2020 at 10:34:53AM -0700, Stefano Stabellini wrote: > Would you be in favor of a more flexible check along the lines of the > one proposed in the patch that started this thread: > > if (xen_vring_use_dma()) > return true; > > > xen_vring_use_dma would be

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-07-01 Thread Michael S. Tsirkin
On Wed, Jul 01, 2020 at 10:34:53AM -0700, Stefano Stabellini wrote: > On Wed, 1 Jul 2020, Christoph Hellwig wrote: > > On Mon, Jun 29, 2020 at 04:46:09PM -0700, Stefano Stabellini wrote: > > > > I could imagine some future Xen hosts setting a flag somewhere in the > > > > platform capability

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-07-01 Thread Stefano Stabellini
On Wed, 1 Jul 2020, Christoph Hellwig wrote: > On Mon, Jun 29, 2020 at 04:46:09PM -0700, Stefano Stabellini wrote: > > > I could imagine some future Xen hosts setting a flag somewhere in the > > > platform capability saying "no xen specific flag, rely on > > > "VIRTIO_F_ACCESS_PLATFORM". Then you

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-07-01 Thread Christoph Hellwig
On Mon, Jun 29, 2020 at 04:46:09PM -0700, Stefano Stabellini wrote: > > I could imagine some future Xen hosts setting a flag somewhere in the > > platform capability saying "no xen specific flag, rely on > > "VIRTIO_F_ACCESS_PLATFORM". Then you set that accordingly in QEMU. > > How about that? >

RE: [PATCH] xen: introduce xen_vring_use_dma

2020-06-29 Thread Peng Fan
> Subject: RE: [PATCH] xen: introduce xen_vring_use_dma > > On Mon, 29 Jun 2020, Peng Fan wrote: > > > > If that is the case, how is it possible that virtio breaks on ARM > > > > using the default dma_ops? The breakage is not Xen related (except > > >

RE: [PATCH] xen: introduce xen_vring_use_dma

2020-06-29 Thread Stefano Stabellini
On Mon, 29 Jun 2020, Peng Fan wrote: > > > If that is the case, how is it possible that virtio breaks on ARM > > > using the default dma_ops? The breakage is not Xen related (except > > > that Xen turns dma_ops on). The original message from Peng was: > > > > > > vring_map_one_sg ->

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-29 Thread Stefano Stabellini
On Fri, 26 Jun 2020, Michael S. Tsirkin wrote: > On Thu, Jun 25, 2020 at 10:31:27AM -0700, Stefano Stabellini wrote: > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > On Wed, Jun 24, 2020 at 02:53:54PM -0700, Stefano Stabellini wrote: > > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: >

RE: [PATCH] xen: introduce xen_vring_use_dma

2020-06-29 Thread Peng Fan
> Subject: Re: [PATCH] xen: introduce xen_vring_use_dma > > On Mon, Jun 29, 2020 at 06:25:41AM +, Peng Fan wrote: > > > > > > Anyway, re-reading the last messages of the original thread > > > > > > [1], it looks like Peng had a clear idea

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-29 Thread Michael S. Tsirkin
On Mon, Jun 29, 2020 at 06:25:41AM +, Peng Fan wrote: > > > > > Anyway, re-reading the last messages of the original thread [1], > > > > > it looks like Peng had a clear idea on how to fix the general issue. > > > > > Peng, what happened with that? > > > > > > We shrinked the rpmsg reserved

RE: [PATCH] xen: introduce xen_vring_use_dma

2020-06-29 Thread Peng Fan
> Subject: Re: [PATCH] xen: introduce xen_vring_use_dma > > On Mon, Jun 29, 2020 at 03:05:19AM +, Peng Fan wrote: > > > Subject: Re: [PATCH] xen: introduce xen_vring_use_dma > > > > > > On Thu, Jun 25, 2020 at 10:31:27AM -0700, Stefano Stabellini wrote: &g

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-29 Thread Michael S. Tsirkin
On Mon, Jun 29, 2020 at 03:05:19AM +, Peng Fan wrote: > > Subject: Re: [PATCH] xen: introduce xen_vring_use_dma > > > > On Thu, Jun 25, 2020 at 10:31:27AM -0700, Stefano Stabellini wrote: > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > > O

RE: [PATCH] xen: introduce xen_vring_use_dma

2020-06-28 Thread Peng Fan
> Subject: Re: [PATCH] xen: introduce xen_vring_use_dma > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > On Wed, Jun 24, 2020 at 02:53:54PM -0700, Stefano Stabellini wrote: > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > > On Wed, Jun 2

RE: [PATCH] xen: introduce xen_vring_use_dma

2020-06-28 Thread Peng Fan
> Subject: Re: [PATCH] xen: introduce xen_vring_use_dma > > On Thu, Jun 25, 2020 at 10:31:27AM -0700, Stefano Stabellini wrote: > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > On Wed, Jun 24, 2020 at 02:53:54PM -0700, Stefano Stabellini wrote: > > >

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-26 Thread Michael S. Tsirkin
On Thu, Jun 25, 2020 at 10:31:27AM -0700, Stefano Stabellini wrote: > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > On Wed, Jun 24, 2020 at 02:53:54PM -0700, Stefano Stabellini wrote: > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > > On Wed, Jun 24, 2020 at 10:59:47AM -0700,

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-25 Thread Stefano Stabellini
On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > On Wed, Jun 24, 2020 at 02:53:54PM -0700, Stefano Stabellini wrote: > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > On Wed, Jun 24, 2020 at 10:59:47AM -0700, Stefano Stabellini wrote: > > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: >

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-24 Thread Michael S. Tsirkin
On Wed, Jun 24, 2020 at 02:53:54PM -0700, Stefano Stabellini wrote: > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > On Wed, Jun 24, 2020 at 10:59:47AM -0700, Stefano Stabellini wrote: > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > > On Wed, Jun 24, 2020 at 05:17:32PM +0800, Peng

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-24 Thread Stefano Stabellini
On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > On Wed, Jun 24, 2020 at 10:59:47AM -0700, Stefano Stabellini wrote: > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > On Wed, Jun 24, 2020 at 05:17:32PM +0800, Peng Fan wrote: > > > > Export xen_swiotlb for all platforms using xen swiotlb > >

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-24 Thread Michael S. Tsirkin
On Wed, Jun 24, 2020 at 10:59:47AM -0700, Stefano Stabellini wrote: > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > On Wed, Jun 24, 2020 at 05:17:32PM +0800, Peng Fan wrote: > > > Export xen_swiotlb for all platforms using xen swiotlb > > > > > > Use xen_swiotlb to determine when vring

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-24 Thread Stefano Stabellini
On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > On Wed, Jun 24, 2020 at 05:17:32PM +0800, Peng Fan wrote: > > Export xen_swiotlb for all platforms using xen swiotlb > > > > Use xen_swiotlb to determine when vring should use dma APIs to map the > > ring: when xen_swiotlb is enabled the dma API is

Re: [PATCH] xen: introduce xen_vring_use_dma

2020-06-24 Thread Michael S. Tsirkin
On Wed, Jun 24, 2020 at 05:17:32PM +0800, Peng Fan wrote: > Export xen_swiotlb for all platforms using xen swiotlb > > Use xen_swiotlb to determine when vring should use dma APIs to map the > ring: when xen_swiotlb is enabled the dma API is required. When it is > disabled, it is not required. >

[PATCH] xen: introduce xen_vring_use_dma

2020-06-24 Thread Peng Fan
Export xen_swiotlb for all platforms using xen swiotlb Use xen_swiotlb to determine when vring should use dma APIs to map the ring: when xen_swiotlb is enabled the dma API is required. When it is disabled, it is not required. Signed-off-by: Peng Fan --- V2: This is a modified version from