From 1c74f10b54f3f603797dcd1b9db3e516b4f2eb7c Mon Sep 17 00:00:00 2001
From: Felix Kuehling <Felix.Kuehling@amd.com>
Date: Wed, 12 Jul 2017 17:08:28 -0400
Subject: [PATCH 0844/4131] drm/amdgpu: Rework ptrace access function

This is based on code review feedback from the amd-gfx:

* Move common code and system memory handling into TTM
* Handle VRAM and optionally private pools in driver callback
* Kmap only system memory pages that are accessed, one page at a time
* Swap in system memory BOs if needed
* Add range check

Change-Id: Id01a6675b2af9bd3400416c18b66c1baefc1c4f1
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Kalyan Alle <kalyan.alle@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 109 +-------------------------------
 1 file changed, 1 insertion(+), 108 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 94e7611..9ae5fda 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1567,113 +1567,7 @@ void amdgpu_ttm_set_active_vram_size(struct amdgpu_device *adev, u64 size)
 }
 
 static struct vm_operations_struct amdgpu_ttm_vm_ops;
-static const struct vm_operations_struct *ttm_vm_ops /* = NULL;
-						      * (appease checkpatch) */;
-static int amdgpu_ttm_bo_access_vram(struct amdgpu_bo *abo,
-				     unsigned long offset,
-				     void *buf, int len, int write)
-{
-	struct amdgpu_device *adev = amdgpu_ttm_adev(abo->tbo.bdev);
-	struct drm_mm_node *nodes = abo->tbo.mem.mm_node;
-	uint32_t value = 0;
-	int result = 0;
-	uint64_t pos;
-	unsigned long flags;
-
-	while (offset >= (nodes->size << PAGE_SHIFT)) {
-		offset -= nodes->size << PAGE_SHIFT;
-		++nodes;
-	}
-	pos = (nodes->start << PAGE_SHIFT) + offset;
-
-	while (len && pos < adev->mc.mc_vram_size) {
-		uint64_t aligned_pos = pos & ~(uint64_t)3;
-		uint32_t bytes = 4 - (pos & 3);
-		uint32_t shift = (pos & 3) * 8;
-		uint32_t mask = 0xffffffff << shift;
-
-		if (len < bytes) {
-			mask &= 0xffffffff >> (bytes - len) * 8;
-			bytes = len;
-		}
-
-		spin_lock_irqsave(&adev->mmio_idx_lock, flags);
-		WREG32(mmMM_INDEX, ((uint32_t)aligned_pos) | 0x80000000);
-		WREG32(mmMM_INDEX_HI, aligned_pos >> 31);
-		if (!write || mask != 0xffffffff)
-			value = RREG32(mmMM_DATA);
-		if (write) {
-			value &= ~mask;
-			value |= (*(uint32_t *)buf << shift) & mask;
-			WREG32(mmMM_DATA, value);
-		}
-		spin_unlock_irqrestore(&adev->mmio_idx_lock, flags);
-		if (!write) {
-			value = (value & mask) >> shift;
-			memcpy(buf, &value, bytes);
-		}
-
-		result += bytes;
-		buf = (uint8_t *)buf + bytes;
-		pos += bytes;
-		len -= bytes;
-		if (pos >= (nodes->start + nodes->size) << PAGE_SHIFT) {
-			++nodes;
-			pos = (nodes->start << PAGE_SHIFT);
-		}
-	}
-
-	return result;
-}
-
-static int amdgpu_ttm_bo_access_kmap(struct amdgpu_bo *abo,
-				     unsigned long offset,
-				     void *buf, int len, int write)
-{
-	struct ttm_buffer_object *bo = &abo->tbo;
-	struct ttm_bo_kmap_obj map;
-	void *ptr;
-	bool is_iomem;
-	int r;
-
-	r = ttm_bo_kmap(bo, 0, bo->num_pages, &map);
-	if (r)
-		return r;
-	ptr = (uint8_t *)ttm_kmap_obj_virtual(&map, &is_iomem) + offset;
-	WARN_ON(is_iomem);
-	if (write)
-		memcpy(ptr, buf, len);
-	else
-		memcpy(buf, ptr, len);
-	ttm_bo_kunmap(&map);
-
-	return len;
-}
-
-static int amdgpu_ttm_vm_access(struct vm_area_struct *vma, unsigned long addr,
-				void *buf, int len, int write)
-{
-	unsigned long offset = (addr) - vma->vm_start;
-	struct ttm_buffer_object *bo = vma->vm_private_data;
-	struct amdgpu_bo *abo = container_of(bo, struct amdgpu_bo, tbo);
-	unsigned domain;
-	int result;
-
-	result = amdgpu_bo_reserve(abo, false);
-	if (result != 0)
-		return result;
-
-	domain = amdgpu_mem_type_to_domain(bo->mem.mem_type);
-	if (domain == AMDGPU_GEM_DOMAIN_VRAM)
-		result = amdgpu_ttm_bo_access_vram(abo, offset,
-						   buf, len, write);
-	else
-		result = amdgpu_ttm_bo_access_kmap(abo, offset,
-						   buf, len, write);
-	amdgpu_bo_unreserve(abo);
-
-	return len;
-}
+static const struct vm_operations_struct *ttm_vm_ops;
 
 int amdgpu_bo_mmap(struct file *filp, struct vm_area_struct *vma,
 		   struct ttm_bo_device *bdev)
@@ -1687,7 +1581,6 @@ int amdgpu_bo_mmap(struct file *filp, struct vm_area_struct *vma,
 	if (unlikely(ttm_vm_ops == NULL)) {
 		ttm_vm_ops = vma->vm_ops;
 		amdgpu_ttm_vm_ops = *ttm_vm_ops;
-		amdgpu_ttm_vm_ops.access = &amdgpu_ttm_vm_access;
 	}
 	vma->vm_ops = &amdgpu_ttm_vm_ops;
 
-- 
2.7.4