similar to: [RFC LINUX PATCH 0/2] Virtio ring works with DMA coherent memory

RPMsg uses dma_alloc_coherent() to allocate memory to shared with the remote. In this case, as there is no pages setup in the dma_alloc_coherent(), we cannot get the physical address back from the virtual address, and thus, we can set the sg_dma_addr to store the DMA address and mark it already DMA mapped. When virtio vring sees the sg_dma_addr is ready set, do not call dma_map_page(). The issue

RPMsg uses dma_alloc_coherent() to allocate memory to shared with the remote. In this case, as there is no pages setup in the dma_alloc_coherent(), we cannot get the physical address back from the virtual address, and thus, we can set the sg_dma_addr to store the DMA address and mark it already DMA mapped. When virtio vring sees the sg_dma_addr is ready set, do not call dma_map_page(). The issue

RPMsg uses dma_alloc_coherent() to allocate memory to shared with the remote. In this case, as there is no pages setup in the dma_alloc_coherent(), we cannot get the physical address back from the virtual address, and thus, we can set the sg_dma_addr to store the DMA address and mark it already DMA mapped. When virtio vring sees the sg_dma_addr is ready set, do not call dma_map_page(). The issue

RPMsg uses dma_alloc_coherent() to allocate memory to shared with the remote. In this case, as there is no pages setup in the dma_alloc_coherent(), we cannot get the physical address back from the virtual address, and thus, we can set the sg_dma_addr to store the DMA address and mark it already DMA mapped. When virtio vring sees the sg_dma_addr is ready set, do not call dma_map_page(). The issue

RPMsg uses dma_alloc_coherent() to allocate memory to shared with the remote. In this case, as there is no pages setup in the dma_alloc_coherent(), we cannot get the physical address back from the virtual address, and thus, we can set the sg_dma_addr to store the DMA address and mark it already DMA mapped. When virtio vring sees the sg_dma_addr is ready set, do not call dma_map_page(). The issue

RPMsg uses dma_alloc_coherent() to allocate memory to shared with the remote. In this case, as there is no pages setup in the dma_alloc_coherent(), we cannot get the physical address back from the virtual address, and thus, we can set the sg_dma_addr to store the DMA address and mark it already DMA mapped. When virtio vring sees the sg_dma_addr is ready set, do not call dma_map_page(). The issue

On Wed, Dec 07, 2016 at 10:59:12PM -0800, Wendy Liang wrote: > If sg is already dma mapped, do not call dma_map_page() in > vring_map_one_sg(). > > In case of rpmsg, rpmsg uses dma_alloc_coherent() to allocate > memory to share with the remote. There is no pages setup > in dma_alloc_coherent(). > > In this case, we cannot convert the virtual address back to the >

On Wed, Dec 07, 2016 at 10:59:12PM -0800, Wendy Liang wrote: > If sg is already dma mapped, do not call dma_map_page() in > vring_map_one_sg(). > > In case of rpmsg, rpmsg uses dma_alloc_coherent() to allocate > memory to share with the remote. There is no pages setup > in dma_alloc_coherent(). > > In this case, we cannot convert the virtual address back to the >

On 2016?12?07? 02:21, Wendy Liang wrote: > RPMsg uses dma_alloc_coherent() to allocate memory to shared with the remote. > In this case, as there is no pages setup in the dma_alloc_coherent(), > we cannot get the physical address back from the virtual address, and thus, > we can set the sg_dma_addr to store the DMA address and mark it already DMA > mapped. > > When virtio

On Thu, May 7, 2015 at 3:28 AM, Edgar E. Iglesias <edgar.iglesias at gmail.com> wrote: > > On Wed, May 06, 2015 at 03:51:48PM +0930, Rusty Russell wrote: > > "Edgar E. Iglesias" <edgar.iglesias at gmail.com> writes: > > > From: "Edgar E. Iglesias" <edgar.iglesias at xilinx.com> > > > > > > Signed-off-by: Edgar E. Iglesias

On Thu, May 7, 2015 at 3:28 AM, Edgar E. Iglesias <edgar.iglesias at gmail.com> wrote: > > On Wed, May 06, 2015 at 03:51:48PM +0930, Rusty Russell wrote: > > "Edgar E. Iglesias" <edgar.iglesias at gmail.com> writes: > > > From: "Edgar E. Iglesias" <edgar.iglesias at xilinx.com> > > > > > > Signed-off-by: Edgar E. Iglesias

"Edgar E. Iglesias" <edgar.iglesias at gmail.com> writes: > From: "Edgar E. Iglesias" <edgar.iglesias at xilinx.com> > > Signed-off-by: Edgar E. Iglesias <edgar.iglesias at xilinx.com> First off, I have handed maintainership off to Michael S. Tsirkin, so his word is now law. That said... there's nothing fundamentally *wrong* with this, but

"Edgar E. Iglesias" <edgar.iglesias at gmail.com> writes: > From: "Edgar E. Iglesias" <edgar.iglesias at xilinx.com> > > Signed-off-by: Edgar E. Iglesias <edgar.iglesias at xilinx.com> First off, I have handed maintainership off to Michael S. Tsirkin, so his word is now law. That said... there's nothing fundamentally *wrong* with this, but

If sg is already dma mapped, do not call dma_map_page() in vring_map_one_sg(). In case of rpmsg, rpmsg uses dma_alloc_coherent() to allocate memory to share with the remote. There is no pages setup in dma_alloc_coherent(). In this case, we cannot convert the virtual address back to the physical address. In this case, we can setup the sg_dma_addr to store the DMA address, and also mark the sg is

If sg is already dma mapped, do not call dma_map_page() in vring_map_one_sg(). In case of rpmsg, rpmsg uses dma_alloc_coherent() to allocate memory to share with the remote. There is no pages setup in dma_alloc_coherent(). In this case, we cannot convert the virtual address back to the physical address. In this case, we can setup the sg_dma_addr to store the DMA address, and also mark the sg is

> 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: > > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > > > On Wed, Jun 24, 2020 at

> 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: > > > > On Wed, 24 Jun 2020, Michael S. Tsirkin wrote: > > > > > On Wed, Jun 24, 2020 at

From: "Edgar E. Iglesias" <edgar.iglesias at xilinx.com> I'm trying to run rpmsg and remoteproc on the ZynqMP (arm64) but I'm hitting a DMA/mm error. The issue was discussed here: http://lists.infradead.org/pipermail/linux-arm-kernel/2015-March/333050.html Russel King pointed out that the arm64 is not doing anything wrong by returning vmapped memory (which is incompatible

From: "Edgar E. Iglesias" <edgar.iglesias at xilinx.com> I'm trying to run rpmsg and remoteproc on the ZynqMP (arm64) but I'm hitting a DMA/mm error. The issue was discussed here: http://lists.infradead.org/pipermail/linux-arm-kernel/2015-March/333050.html Russel King pointed out that the arm64 is not doing anything wrong by returning vmapped memory (which is incompatible

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: > > > > > On Wed, Jun 24, 2020 at 05:17:32PM +0800, Peng