gpu: nvgpu: support usermode submit buffers

Import userd and gpfifo buffers from userspace if provided via
NVGPU_IOCTL_CHANNEL_ALLOC_GPFIFO_EX. Also supply the work submit token
(i.e., the hw channel id) to userspace.

To keep the buffers alive, store their dmabuf and attachment/sgt handles
in nvgpu_channel_linux. Our nvgpu_mem doesn't provide such data for
buffers that are mainly in kernel use. The buffers are freed via a new
API in the os_channel interface.

Fix a bug in gk20a_channel_free_usermode_buffers: also unmap the
usermode gpfifo buffer.

Bug 200145225
Bug 200541476

Change-Id: I8416af7085c91b044ac8ccd9faa38e2a6d0c3946
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1795821
Signed-off-by: Debarshi Dutta <ddutta@nvidia.com>
(cherry picked from commit 99b1c6dcdf328efcfe47338ad1b71a114ab7f272
in dev-main)
Reviewed-on: https://git-master.nvidia.com/r/2170603
GVS: Gerrit_Virtual_Submit
Reviewed-by: Bibek Basu <bbasu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

2 files changed, 4 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/include/nvgpu/channel.h b/drivers/gpu/nvgpu/include/nvgpu/channel.h
index d7bf7816..7ca60fe3 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/channel.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/channel.h
@@ -95,7 +95,9 @@ struct nvgpu_setup_bind_args {
         u32 num_gpfifo_entries;
         u32 num_inflight_jobs;
         u32 userd_dmabuf_fd;
+        u64 userd_dmabuf_offset;
         u32 gpfifo_dmabuf_fd;
+        u64 gpfifo_dmabuf_offset;
         u32 work_submit_token;
         u32 flags;
 };
diff --git a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
index feae7d23..873fa826 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/gk20a.h
@@ -1605,7 +1605,8 @@ struct gk20a {
                                 struct nvgpu_gpfifo_userdata userdata,
                                 u32 start, u32 length);
                 int (*alloc_usermode_buffers)(struct channel_gk20a *c,
-                        struct nvgpu_setup_bind_args *gpfifo_args);
+                        struct nvgpu_setup_bind_args *args);
+                void (*free_usermode_buffers)(struct channel_gk20a *c);
         } os_channel;
 
         struct gk20a_scale_profile *scale_profile;