gpu: nvgpu: Add nvgpu_os_buffer

Add a generic nvgpu_os_buffer type, defined by each OS, to abstract
a "user" buffer. This allows the comptag interface to be used in the
core code.

The end goal of this patch is to allow the OS specific mapping code
to call a generic mapping function that handles most of the mapping
logic. The problem is a lot of the logic involves comptags which are
highly dependent on the operating systems buffer management scheme.
With this, each OS can implement the buffer comptag mechanics
however it wishes without the core MM code caring.

JIRA NVGPU-30
JIRA NVGPU-223

Change-Id: Iaf64bc52e01ef3f262b4f8f9173a84384db7dc3e
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1583986
Reviewed-by: Automatic_Commit_Validation_User
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>

3 files changed, 24 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/include/nvgpu/comptags.h b/drivers/gpu/nvgpu/include/nvgpu/comptags.h
index 6e3062ec..5482d0ce 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/comptags.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/comptags.h
@@ -20,6 +20,7 @@
 #include <nvgpu/lock.h>
 
 struct gk20a;
+struct nvgpu_os_buffer;
 
 struct gk20a_comptags {
         u32 offset;
@@ -52,6 +53,17 @@ int gk20a_comptaglines_alloc(struct gk20a_comptag_allocator *allocator,
 void gk20a_comptaglines_free(struct gk20a_comptag_allocator *allocator,
                              u32 offset, u32 len);
 
+/*
+ * Defined by OS specific code since comptags are stored in a highly OS specific
+ * way.
+ */
+int gk20a_alloc_comptags(struct gk20a *g,
+                         struct nvgpu_os_buffer *buf,
+                         struct gk20a_comptag_allocator *allocator,
+                         u32 lines);
+void gk20a_get_comptags(struct nvgpu_os_buffer *buf,
+                        struct gk20a_comptags *comptags);
+
 
 
 #endif
diff --git a/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h b/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
index dee8fa09..39deeb69 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
@@ -33,11 +33,17 @@
 
 struct sg_table;
 struct dma_buf;
+struct device;
 
 struct vm_gk20a;
 struct vm_gk20a_mapping_batch;
 struct nvgpu_vm_area;
 
+struct nvgpu_os_buffer {
+        struct dma_buf *dmabuf;
+        struct device *dev;
+};
+
 /* NVGPU_AS_MAP_BUFFER_FLAGS_DIRECT_KIND_CTRL must be set */
 int nvgpu_vm_map_linux(struct vm_gk20a *vm,
                        struct dma_buf *dmabuf,
diff --git a/drivers/gpu/nvgpu/include/nvgpu/vm.h b/drivers/gpu/nvgpu/include/nvgpu/vm.h
index 10a7f7ce..b91b41e4 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/vm.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/vm.h
@@ -107,6 +107,12 @@ struct nvgpu_mapped_buf {
         bool va_allocated;
 };
 
+/*
+ * Defined by each OS. Allows the common VM code do things to the OS specific
+ * buffer structures.
+ */
+struct nvgpu_os_buffer;
+
 static inline struct nvgpu_mapped_buf *
 nvgpu_mapped_buf_from_buffer_list(struct nvgpu_list_node *node)
 {