drm/nouveau/core/mm: allow to find nvkm_vma from offset

Need this as we can not lookup regular process vma from page table
synchronization callback.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>

4 files changed, 43 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/include/nvkm/core/mm.h b/drivers/gpu/drm/nouveau/include/nvkm/core/mm.h
index edaad5265d52..95f6a8d71559 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/core/mm.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/core/mm.h
@@ -14,6 +14,7 @@ struct nvkm_mm_node {
 	u8  type;
 	u64 offset;
 	u64 length;
+	void *data;
 };
 
 struct nvkm_mm {
@@ -41,6 +42,7 @@ int  nvkm_mm_tail(struct nvkm_mm *, u8 heap, u8 type, u64 size_max,
 		  u64 size_min, u64 align, struct nvkm_mm_node **);
 void nvkm_mm_free(struct nvkm_mm *, struct nvkm_mm_node **);
 void nvkm_mm_dump(struct nvkm_mm *, const char *);
+struct nvkm_mm_node *nvkm_mm_find(struct nvkm_mm *mm, u64 start, u64 end);
 
 static inline bool
 nvkm_mm_contiguous(struct nvkm_mm_node *node)
diff --git a/drivers/gpu/drm/nouveau/include/nvkm/subdev/mmu.h b/drivers/gpu/drm/nouveau/include/nvkm/subdev/mmu.h
index 069c20940740..40022c496087 100644
--- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/mmu.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/mmu.h
@@ -54,6 +54,7 @@ void nvkm_vm_map(struct nvkm_vma *, struct nvkm_mem *);
 void nvkm_vm_map_at(struct nvkm_vma *, u64 offset, u64 length, struct nvkm_mem *);
 void nvkm_vm_unmap(struct nvkm_vma *);
 void nvkm_vm_unmap_at(struct nvkm_vma *, u64 offset, u64 length);
+struct nvkm_vma *nvkm_vm_find(struct nvkm_vm *vm, u64 start, u64 end);
 
 int nvkm_vmm_new(struct nvkm_mmu *, u64 addr, u64 size, void *argv, u32 argc,
 		 struct lock_class_key *, struct nvkm_vmm **);
diff --git a/drivers/gpu/drm/nouveau/nvkm/core/mm.c b/drivers/gpu/drm/nouveau/nvkm/core/mm.c
index a38630804139..f66197733bb0 100644
--- a/drivers/gpu/drm/nouveau/nvkm/core/mm.c
+++ b/drivers/gpu/drm/nouveau/nvkm/core/mm.c
@@ -207,6 +207,18 @@ nvkm_mm_fix(struct nvkm_mm *mm,
 	return -ENOSPC;
 }
 
+struct nvkm_mm_node *nvkm_mm_find(struct nvkm_mm *mm, u64 start, u64 end)
+{
+	struct nvkm_mm_node *this;
+
+	list_for_each_entry (this, &mm->nodes, nl_entry) {
+		if (start >= this->offset && (this->offset + this->length) >= end)
+			return this;
+	}
+
+	return NULL;
+}
+
 static struct nvkm_mm_node *
 region_tail(struct nvkm_mm *mm, struct nvkm_mm_node *a, u64 size)
 {
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/base.c
index b1afd964d5cc..d16d19386425 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/base.c
@@ -297,6 +297,7 @@ nvkm_vm_get(struct nvkm_vm *vm, u64 size, u32 page_shift, u32 access,
 		mutex_unlock(&vm->mutex);
 		return ret;
 	}
+	vma->node->data = vma;
 
 	fpde = (vma->node->offset >> mmu->func->pgt_bits);
 	lpde = (vma->node->offset + vma->node->length - 1) >> mmu->func->pgt_bits;
@@ -344,6 +345,7 @@ nvkm_vm_get_fix(struct nvkm_vm *vm, u64 offset, u64 size, u32 page_shift,
 		mutex_unlock(&vm->mutex);
 		return ret;
 	}
+	vma->node->data = vma;
 
 	fpde = (vma->node->offset >> mmu->func->pgt_bits);
 	lpde = (vma->node->offset + vma->node->length - 1) >> mmu->func->pgt_bits;
@@ -398,6 +400,32 @@ nvkm_vm_put(struct nvkm_vma *vma)
 	nvkm_vm_ref(NULL, &vma->vm, NULL);
 }
 
+struct nvkm_vma *nvkm_vm_find(struct nvkm_vm *vm, u64 start, u64 end)
+{
+	struct nvkm_vma *vma = NULL;
+	struct nvkm_mm_node *node;
+
+	mutex_lock(&vm->mutex);
+again:
+	node = nvkm_mm_find(&vm->mm, start >> 12, end >> 12);
+	if (node) {
+		vma = node->data;
+		if (vma) {
+			if (vma->refcount <= 0) {
+				start = (node->offset + node->length) << 12;
+				if (start < end)
+					goto again;
+				vma = NULL;
+			} else {
+				vma->refcount++;
+			}
+		}
+	}
+	mutex_unlock(&vm->mutex);
+
+	return vma;
+}
+
 int
 nvkm_vm_boot(struct nvkm_vm *vm, u64 size)
 {