gpu: nvgpu: VM map path refactoring

Final VM mapping refactoring. Move most of the logic in the VM
map path to the common/mm/vm.c code and use the generic APIs
previously implemented to deal with comptags and map caching.

This also updates the mapped_buffer struct to finally be free
of the Linux dma_buf and scatter gather table pointers. This
is replaced with the nvgpu_os_buffer struct.

JIRA NVGPU-30
JIRA NVGPU-71
JIRA NVGPU-224

Change-Id: If5b32886221c3e5af2f3d7ddd4fa51dd487bb981
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1583987
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>

2 files changed, 49 insertions, 9 deletions

diff --git a/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h b/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
index 39deeb69..d9f082af 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
@@ -44,6 +44,11 @@ struct nvgpu_os_buffer {
         struct device *dev;
 };
 
+struct nvgpu_mapped_buf_priv {
+        struct dma_buf *dmabuf;
+        struct sg_table *sgt;
+};
+
 /* 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 b91b41e4..d501b98f 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/vm.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/vm.h
@@ -37,6 +37,18 @@ struct vm_gk20a;
 struct nvgpu_vm_area;
 struct gk20a_comptag_allocator;
 
+/*
+ * Defined by each OS. Allows the common VM code do things to the OS specific
+ * buffer structures.
+ */
+struct nvgpu_os_buffer;
+
+#ifdef __KERNEL__
+#include <nvgpu/linux/vm.h>
+#else
+/* QNX include goes here. */
+#endif
+
 /**
  * This header contains the OS agnostic APIs for dealing with VMs. Most of the
  * VM implementation is system specific - it must translate from a platform's
@@ -89,13 +101,12 @@ struct nvgpu_mapped_buf {
         struct vm_gk20a *vm;
         struct nvgpu_vm_area *vm_area;
 
+        struct nvgpu_ref ref;
+
         struct nvgpu_rbtree_node node;
         struct nvgpu_list_node buffer_list;
         u64 addr;
         u64 size;
-        struct dma_buf *dmabuf;
-        struct sg_table *sgt;
-        struct nvgpu_ref ref;
 
         u32 pgsz_idx;
         u32 ctag_offset;
@@ -105,13 +116,16 @@ struct nvgpu_mapped_buf {
         u32 flags;
         u32 kind;
         bool va_allocated;
-};
 
-/*
- * Defined by each OS. Allows the common VM code do things to the OS specific
- * buffer structures.
- */
-struct nvgpu_os_buffer;
+        /*
+         * Separate from the nvgpu_os_buffer struct to clearly distinguish
+         * lifetime. A nvgpu_mapped_buf_priv will _always_ be wrapped by a
+         * struct nvgpu_mapped_buf; however, there are times when a struct
+         * nvgpu_os_buffer would be separate. This aims to prevent dangerous
+         * usage of container_of() or the like in OS code.
+         */
+        struct nvgpu_mapped_buf_priv os_priv;
+};
 
 static inline struct nvgpu_mapped_buf *
 nvgpu_mapped_buf_from_buffer_list(struct nvgpu_list_node *node)
@@ -226,6 +240,25 @@ void nvgpu_vm_put_buffers(struct vm_gk20a *vm,
                           struct nvgpu_mapped_buf **mapped_buffers,
                           int num_buffers);
 
+struct nvgpu_mapped_buf *nvgpu_vm_find_mapping(struct vm_gk20a *vm,
+                                               struct nvgpu_os_buffer *os_buf,
+                                               u64 map_addr,
+                                               u32 flags,
+                                               int kind);
+
+struct nvgpu_mapped_buf *nvgpu_vm_map(struct vm_gk20a *vm,
+                                      struct nvgpu_os_buffer *os_buf,
+                                      struct nvgpu_sgt *sgt,
+                                      u64 map_addr,
+                                      u64 map_size,
+                                      u64 phys_offset,
+                                      int rw,
+                                      u32 flags,
+                                      s16 compr_kind,
+                                      s16 incompr_kind,
+                                      struct vm_gk20a_mapping_batch *batch,
+                                      enum nvgpu_aperture aperture);
+
 void nvgpu_vm_unmap(struct vm_gk20a *vm, u64 offset,
                     struct vm_gk20a_mapping_batch *batch);
 
@@ -240,6 +273,8 @@ void nvgpu_vm_unmap_system(struct nvgpu_mapped_buf *mapped_buffer);
  */
 void __nvgpu_vm_unmap_ref(struct nvgpu_ref *ref);
 
+u64 nvgpu_os_buf_get_size(struct nvgpu_os_buffer *os_buf);
+
 /*
  * These all require the VM update lock to be held.
  */