drm/xe: Pick correct userptr VMA to repin on REMAP op failure

A REMAP op is composed of 3 VMA's - unmap, prev map, and next map. When
op_execute fails with -EAGAIN we need to update the local VMA pointer to
the current op state and then repin the VMA if it is a userptr.

Fixes a failure seen in xe_vm.munmap-style-unbind-userptr-one-partial.

Fixes: b06d47be ("drm/xe: Port Xe to GPUVA")
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240201004849.2219558-3-matthew.brost@intel.com
(cherry picked from commit 447f74d2)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

drivers/gpu/drm/xe/xe_vm.c

@@ -2531,13 +2531,25 @@ static int __xe_vma_op_execute(struct xe_vm *vm, struct xe_vma *vma,
 	}
 	drm_exec_fini(&exec);
 
-	if (err == -EAGAIN && xe_vma_is_userptr(vma)) {
+	if (err == -EAGAIN) {
 		lockdep_assert_held_write(&vm->lock);
-		err = xe_vma_userptr_pin_pages(to_userptr_vma(vma));
-		if (!err)
-			goto retry_userptr;
 
-		trace_xe_vma_fail(vma);
+		if (op->base.op == DRM_GPUVA_OP_REMAP) {
+			if (!op->remap.unmap_done)
+				vma = gpuva_to_vma(op->base.remap.unmap->va);
+			else if (op->remap.prev)
+				vma = op->remap.prev;
+			else
+				vma = op->remap.next;
+		}
+
+		if (xe_vma_is_userptr(vma)) {
+			err = xe_vma_userptr_pin_pages(to_userptr_vma(vma));
+			if (!err)
+				goto retry_userptr;
+
+			trace_xe_vma_fail(vma);
+		}
 	}
 
 	return err;