gpu: nvgpu: Split VM interface out

This patch begins the major rework of the GPU's virtual memory manager
(VMM). The VMM is the piece of code that handles the userspace interface
to buffers and their mappings into the GMMU. The core data structure is
the VM - for now still known as 'struct vm_gk20a'. Each one of these
structs represents one addres space to which channels or TSGs may bind
themselves to.

The VMM splits the interface up into two broad categories. First there's
the common, OS independent interfaces; and second there's the OS specific
interfaces.

OS independent
--------------

  This is the code that manages the lifetime of VMs, the buffers inside
  VMs (search, batch mapping) creation, destruction, etc.

OS Specific
-----------

  This handles mapping of buffers represented as they are represented by
  the OS (dma_buf's for example on Linux).

This patch is by no means complete. There's still Linux specific functions
scattered in ostensibly OS independent code. This is the first step. A
patch that rewrites everything in one go would simply be too big to
effectively review.

Instead the goal of this change is to simply separate out the basic
OS specific and OS agnostic interfaces into their own header files. The
next series of patches will start to pull the relevant implementations
into OS specific C files and common C files.

JIRA NVGPU-12
JIRA NVGPU-30

Change-Id: I242c7206047b6c769296226d855b7e44d5c4bfa8
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: http://git-master/r/1464939
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/vm_priv.h b/drivers/gpu/nvgpu/common/linux/vm_priv.h
new file mode 100644
index 00000000..c0fb0ffe
--- /dev/null
+++ b/drivers/gpu/nvgpu/common/linux/vm_priv.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2017, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __COMMON_LINUX_VM_PRIV_H__
+#define __COMMON_LINUX_VM_PRIV_H__
+
+#include <nvgpu/types.h>
+
+struct sg_table;
+struct dma_buf;
+
+struct vm_gk20a;
+struct vm_gk20a_mapping_batch;
+
+u64 nvgpu_vm_map(struct vm_gk20a *vm,
+                 struct dma_buf *dmabuf,
+                 u64 offset_align,
+                 u32 flags /*NVGPU_AS_MAP_BUFFER_FLAGS_*/,
+                 int kind,
+                 struct sg_table **sgt,
+                 bool user_mapped,
+                 int rw_flag,
+                 u64 buffer_offset,
+                 u64 mapping_size,
+                 struct vm_gk20a_mapping_batch *mapping_batch);
+
+int nvgpu_vm_map_compbits(struct vm_gk20a *vm,
+                          u64 mapping_gva,
+                          u64 *compbits_win_gva,
+                          u64 *mapping_iova,
+                          u32 flags);
+
+/* Note: batch may be NULL if map op is not part of a batch */
+int nvgpu_vm_map_buffer(struct vm_gk20a *vm,
+                        int dmabuf_fd,
+                        u64 *offset_align,
+                        u32 flags, /* NVGPU_AS_MAP_BUFFER_FLAGS_ */
+                        int kind,
+                        u64 buffer_offset,
+                        u64 mapping_size,
+                        struct vm_gk20a_mapping_batch *batch);
+
+void nvgpu_vm_unmap(struct vm_gk20a *vm, u64 offset);
+
+/* find buffer corresponding to va */
+int nvgpu_vm_find_buffer(struct vm_gk20a *vm, u64 gpu_va,
+                         struct dma_buf **dmabuf,
+                         u64 *offset);
+#endif