gpu: nvgpu: abstract away ioctl gpfifo read

The biggest remaining Linuxism in the submit path is the
copy_from_user() calls for reading the gpfifo entries to the HW-visible
buffer. Abstract away the copy of one such segment starting at some
offset and keep the wraparound logic and vidmem proxy in the core submit
path.

Jira NVGPU-705

Change-Id: I0c6438045c695e5e3f5da4fbc0c92d2c6e7f32cb
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1730480
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.h b/drivers/gpu/nvgpu/gk20a/gk20a.h
index 3b8c5cd2..9061236e 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.h
@@ -148,6 +148,14 @@ enum gk20a_cbc_op {
 enum nvgpu_unit;
 
 enum nvgpu_flush_op;
+
+struct _resmgr_context;
+
+struct nvgpu_gpfifo_userdata {
+        struct nvgpu_gpfifo_entry __user *entries;
+        struct _resmgr_context *context;
+};
+
 /*
  * gpu_ops should only contain function pointers! Non-function pointer members
  * should go in struct gk20a or be implemented with the boolean flag API defined
@@ -1488,6 +1496,9 @@ struct gk20a {
                         struct channel_gk20a *ch, const char *fmt, ...);
                 void (*signal_os_fence_framework)(struct channel_gk20a *ch);
                 void (*destroy_os_fence_framework)(struct channel_gk20a *ch);
+                int (*copy_user_gpfifo)(struct nvgpu_gpfifo_entry *dest,
+                                struct nvgpu_gpfifo_userdata userdata,
+                                u32 start, u32 length);
         } os_channel;
 
         struct gk20a_scale_profile *scale_profile;