similar to: [RFC 0/4] rpmsg: Fix init of DMA:able virtqueues

"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

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

From: "Edgar E. Iglesias" <edgar.iglesias at xilinx.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias at xilinx.com> --- drivers/rpmsg/virtio_rpmsg_bus.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c index 73354ee..9ae53a0 100644 ---

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.iglesias at xilinx.com> > > First off, I have handed maintainership off to Michael S. Tsirkin, so >

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

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

virtio spec requires that all drivers set DRIVER_OK before using devices. While rpmsg isn't yet included in the virtio 1 spec, previous spec versions also required this. virtio rpmsg violates this rule: is calls kick before setting DRIVER_OK. The fix isn't trivial since simply calling virtio_device_ready earlier would mean we might get an interrupt in parallel with adding buffers.

virtio spec requires that all drivers set DRIVER_OK before using devices. While rpmsg isn't yet included in the virtio 1 spec, previous spec versions also required this. virtio rpmsg violates this rule: is calls kick before setting DRIVER_OK. The fix isn't trivial since simply calling virtio_device_ready earlier would mean we might get an interrupt in parallel with adding buffers.

Add virtqueue_add_sgs which is more general than virtqueue_add_buf, which makes virtio-scsi and virtio-blk nicer, then add virtqueue_add_inbuf and virtqueue_add_outbuf which handle the more general case, and finally delete virtqueue_add_buf(). I'm hoping this will be the final post of the whole series, and it can move from my pending-rebases tree into virtio-next. Thanks! Rusty. Paolo

Add virtqueue_add_sgs which is more general than virtqueue_add_buf, which makes virtio-scsi and virtio-blk nicer, then add virtqueue_add_inbuf and virtqueue_add_outbuf which handle the more general case, and finally delete virtqueue_add_buf(). I'm hoping this will be the final post of the whole series, and it can move from my pending-rebases tree into virtio-next. Thanks! Rusty. Paolo

checkpatch.pl wants arrays of strings declared as follows: static const char * const names[] = { "vq-1", "vq-2", "vq-3" }; Currently the find_vqs() function takes a const char *names[] argument so passing checkpatch.pl's const char * const names[] results in a compiler error due to losing the second const. This patch adjusts the find_vqs() prototype and

checkpatch.pl wants arrays of strings declared as follows: static const char * const names[] = { "vq-1", "vq-2", "vq-3" }; Currently the find_vqs() function takes a const char *names[] argument so passing checkpatch.pl's const char * const names[] results in a compiler error due to losing the second const. This patch adjusts the find_vqs() prototype and