gpu-paging: Initial working implementation

Supports synchronous page out or in of a specific buffer.

Includes fast reverse struct mapped_buf lookup.

Requires initial set of changes to nvmap as well.

3 files changed, 21 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/include/nvgpu/gmmu.h b/drivers/gpu/nvgpu/include/nvgpu/gmmu.h
index 2fc0d44e..81f829ed 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/gmmu.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/gmmu.h
@@ -354,6 +354,23 @@ int __nvgpu_get_pte(struct gk20a *g, struct vm_gk20a *vm, u64 vaddr, u32 *pte);
  */
 int __nvgpu_set_pte(struct gk20a *g, struct vm_gk20a *vm, u64 vaddr, u32 *pte);
 
+/**
+ * __nvgpu_update_paddr - Remap a virtual address to a new physical address
+ *
+ * @g     - The GPU.
+ * @vm    - VM to look in.
+ * @vaddr - GPU virtual address.
+ * @paddr - The new physical address to map to
+ *
+ * This function is a combination of __nvgpu_get_pte() and __nvgpu_set_pte().
+ * It searches for an existing PTE associated with @vaddr, and then updates
+ * only the physical address pointed to in the PTE to @paddr. All other
+ * attributes/fields of the PTE are preserved.
+ *
+ * This function returns the number of bytes mapped on success and -EINVAL
+ * otherwise.
+ */
+int __nvgpu_update_paddr(struct gk20a *g, struct vm_gk20a *vm, u64 vaddr, u64 paddr);
 
 /*
  * Internal debugging routines. Probably not something you want to use.
diff --git a/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h b/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
index 6f3beaa9..b86a428a 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/linux/vm.h
@@ -49,6 +49,8 @@ struct nvgpu_mapped_buf_priv {
         struct dma_buf *dmabuf;
         struct dma_buf_attachment *attachment;
         struct sg_table *sgt;
+        // For fast reverse lookup (FD -> mapped_buf)
+        struct list_head nvmap_priv_entry;
 };
 
 /* NVGPU_AS_MAP_BUFFER_FLAGS_DIRECT_KIND_CTRL must be set */
diff --git a/drivers/gpu/nvgpu/include/nvgpu/vm.h b/drivers/gpu/nvgpu/include/nvgpu/vm.h
index 3867c745..f007d880 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/vm.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/vm.h
@@ -261,6 +261,8 @@ struct nvgpu_mapped_buf *nvgpu_vm_map(struct vm_gk20a *vm,
                                       struct vm_gk20a_mapping_batch *batch,
                                       enum nvgpu_aperture aperture);
 
+void nvgpu_vm_remap(struct nvgpu_mapped_buf *m);
+
 void nvgpu_vm_unmap(struct vm_gk20a *vm, u64 offset,
                     struct vm_gk20a_mapping_batch *batch);