drm/amdgpu: fix before and after mapping judgement for replace mapping

If the before mapping is 1 page size, so its start and last will be same.
Thus below condition will become false, then to free the before mapping.
   > if (before->it.start != before->it.last)
But in this case, we need the before mapping of 1 page size.
So does after mapping.

Signed-off-by: Junwei Zhang <Jerry.Zhang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 2da0802..1f811ef 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1704,12 +1704,14 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
        before = kzalloc(sizeof(*before), GFP_KERNEL);
        if (!before)
                return -ENOMEM;
+       INIT_LIST_HEAD(&before->list);
 
        after = kzalloc(sizeof(*after), GFP_KERNEL);
        if (!after) {
                kfree(before);
                return -ENOMEM;
        }
+       INIT_LIST_HEAD(&after->list);
 
        /* Now gather all removed mappings */
        it = interval_tree_iter_first(&vm->va, saddr, eaddr);
@@ -1719,7 +1721,7 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
 
                /* Remember mapping split at the start */
                if (tmp->it.start < saddr) {
-                       before->it.start = tmp->it.start;;
+                       before->it.start = tmp->it.start;
                        before->it.last = saddr - 1;
                        before->offset = tmp->offset;
                        before->flags = tmp->flags;
@@ -1754,8 +1756,8 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
                trace_amdgpu_vm_bo_unmap(NULL, tmp);
        }
 
-       /* Insert partial mapping before the range*/
-       if (before->it.start != before->it.last) {
+       /* Insert partial mapping before the range */
+       if (!list_empty(&before->list)) {
                interval_tree_insert(&before->it, &vm->va);
                if (before->flags & AMDGPU_PTE_PRT)
                        amdgpu_vm_prt_get(adev);
@@ -1764,7 +1766,7 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
        }
 
        /* Insert partial mapping after the range */
-       if (after->it.start != after->it.last) {
+       if (!list_empty(&after->list)) {
                interval_tree_insert(&after->it, &vm->va);
                if (after->flags & AMDGPU_PTE_PRT)
                        amdgpu_vm_prt_get(adev);