drm/xe: Port Xe to GPUVA

Rather than open coding VM binds and VMA tracking, use the GPUVA
library. GPUVA provides a common infrastructure for VM binds to use mmap
/ munmap semantics and support for VK sparse bindings.

The concepts are:

1) xe_vm inherits from drm_gpuva_manager
2) xe_vma inherits from drm_gpuva
3) xe_vma_op inherits from drm_gpuva_op
4) VM bind operations (MAP, UNMAP, PREFETCH, UNMAP_ALL) call into the
GPUVA code to generate an VMA operations list which is parsed, committed,
and executed.

v2 (CI): Add break after default in case statement.
v3: Rebase
v4: Fix some error handling
v5: Use unlocked version VMA in error paths
v6: Rebase, address some review feedback mainly Thomas H
v7: Fix compile error in xe_vma_op_unwind, address checkpatch

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

1 files changed, 21 insertions, 10 deletions

diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
index fb351c36cdc2..00b8b5e7f197 100644
--- a/drivers/gpu/drm/xe/xe_bo.c
+++ b/drivers/gpu/drm/xe/xe_bo.c
@@ -412,7 +412,9 @@ static int xe_bo_trigger_rebind(struct xe_device *xe, struct xe_bo *bo,
 {
 	struct dma_resv_iter cursor;
 	struct dma_fence *fence;
-	struct xe_vma *vma;
+	struct drm_gpuva *gpuva;
+	struct drm_gem_object *obj = &bo->ttm.base;
+	struct drm_gpuvm_bo *vm_bo;
 	int ret = 0;
 
 	dma_resv_assert_held(bo->ttm.base.resv);
@@ -425,10 +427,12 @@ static int xe_bo_trigger_rebind(struct xe_device *xe, struct xe_bo *bo,
 		dma_resv_iter_end(&cursor);
 	}
 
-	list_for_each_entry(vma, &bo->vmas, bo_link) {
-		struct xe_vm *vm = xe_vma_vm(vma);
+	drm_gem_for_each_gpuvm_bo(vm_bo, obj) {
+		drm_gpuvm_bo_for_each_va(gpuva, vm_bo) {
+			struct xe_vma *vma = gpuva_to_vma(gpuva);
+			struct xe_vm *vm = xe_vma_vm(vma);
 
-		trace_xe_vma_evict(vma);
+			trace_xe_vma_evict(vma);
 
 		if (xe_vm_in_fault_mode(vm)) {
 			/* Wait for pending binds / unbinds. */
@@ -454,7 +458,6 @@ static int xe_bo_trigger_rebind(struct xe_device *xe, struct xe_bo *bo,
 
 		} else {
 			bool vm_resv_locked = false;
-			struct xe_vm *vm = xe_vma_vm(vma);
 
 			/*
 			 * We need to put the vma on the vm's rebind_list,
@@ -462,9 +465,9 @@ static int xe_bo_trigger_rebind(struct xe_device *xe, struct xe_bo *bo,
 			 * that we indeed have it locked, put the vma an the
 			 * vm's notifier.rebind_list instead and scoop later.
 			 */
-			if (dma_resv_trylock(&vm->resv))
+			if (dma_resv_trylock(xe_vm_resv(vm)))
 				vm_resv_locked = true;
-			else if (ctx->resv != &vm->resv) {
+			else if (ctx->resv != xe_vm_resv(vm)) {
 				spin_lock(&vm->notifier.list_lock);
 				list_move_tail(&vma->notifier.rebind_link,
 					       &vm->notifier.rebind_list);
@@ -477,7 +480,8 @@ static int xe_bo_trigger_rebind(struct xe_device *xe, struct xe_bo *bo,
 				list_add_tail(&vma->rebind_link, &vm->rebind_list);
 
 			if (vm_resv_locked)
-				dma_resv_unlock(&vm->resv);
+				dma_resv_unlock(xe_vm_resv(vm));
+		}
 		}
 	}
 
@@ -1285,7 +1289,7 @@ xe_bo_create_locked_range(struct xe_device *xe,
 		}
 	}
 
-	bo = __xe_bo_create_locked(xe, bo, tile, vm ? &vm->resv : NULL,
+	bo = __xe_bo_create_locked(xe, bo, tile, vm ? xe_vm_resv(vm) : NULL,
 				   vm && !xe_vm_in_fault_mode(vm) &&
 				   flags & XE_BO_CREATE_USER_BIT ?
 				   &vm->lru_bulk_move : NULL, size,
@@ -1293,6 +1297,13 @@ xe_bo_create_locked_range(struct xe_device *xe,
 	if (IS_ERR(bo))
 		return bo;
 
+	/*
+	 * Note that instead of taking a reference no the drm_gpuvm_resv_bo(),
+	 * to ensure the shared resv doesn't disappear under the bo, the bo
+	 * will keep a reference to the vm, and avoid circular references
+	 * by having all the vm's bo refereferences released at vm close
+	 * time.
+	 */
 	if (vm && xe_bo_is_user(bo))
 		xe_vm_get(vm);
 	bo->vm = vm;
@@ -1600,7 +1611,7 @@ int xe_bo_validate(struct xe_bo *bo, struct xe_vm *vm, bool allow_res_evict)
 		xe_vm_assert_held(vm);
 
 		ctx.allow_res_evict = allow_res_evict;
-		ctx.resv = &vm->resv;
+		ctx.resv = xe_vm_resv(vm);
 	}
 
 	return ttm_bo_validate(&bo->ttm, &bo->placement, &ctx);