drm/xe: Assign ioctl xe file handler to vm in xe_vm_create

In several code paths, such as xe_pt_create(), the vm->xef field is used
to determine whether a VM originates from userspace or the kernel.

Previously, this handler was only assigned in xe_vm_create_ioctl(),
after the VM was created by xe_vm_create(). However, xe_vm_create()
triggers page table creation, and that function assumes vm->xef should
be already set. This could lead to incorrect origin detection.

To fix this problem and ensure consistency in the initialization of
the VM object, let's move the assignment of this handler to
xe_vm_create.

v2:
 - take reference to the xe file object only when xef is not NULL
 - release the reference to the xe file object on the error path (Matthew)

Fixes: 7f387e6 ("drm/xe: add XE_BO_FLAG_PINNED_LATE_RESTORE")
Signed-off-by: Piotr Piórkowski <[email protected]>
Cc: Matthew Auld <[email protected]>
Reviewed-by: Matthew Auld <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Michał Winiarski <[email protected]>
(cherry picked from commit 9337166)
Signed-off-by: Rodrigo Vivi <[email protected]>

Author: piorkov

drivers/gpu/drm/xe/xe_migrate.c

@@ -408,7 +408,7 @@ struct xe_migrate *xe_migrate_init(struct xe_tile *tile)
 
 	/* Special layout, prepared below.. */
 	vm = xe_vm_create(xe, XE_VM_FLAG_MIGRATION |
-			  XE_VM_FLAG_SET_TILE_ID(tile));
+			  XE_VM_FLAG_SET_TILE_ID(tile), NULL);
 	if (IS_ERR(vm))
 		return ERR_CAST(vm);
 

drivers/gpu/drm/xe/xe_pxp_submit.c

@@ -101,7 +101,7 @@ static int allocate_gsc_client_resources(struct xe_gt *gt,
 	xe_assert(xe, hwe);
 
 	/* PXP instructions must be issued from PPGTT */
-	vm = xe_vm_create(xe, XE_VM_FLAG_GSC);
+	vm = xe_vm_create(xe, XE_VM_FLAG_GSC, NULL);
 	if (IS_ERR(vm))
 		return PTR_ERR(vm);
 

drivers/gpu/drm/xe/xe_vm.c

@@ -1640,7 +1640,7 @@ static void xe_vm_free_scratch(struct xe_vm *vm)
 	}
 }
 
-struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
+struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags, struct xe_file *xef)
 {
 	struct drm_gem_object *vm_resv_obj;
 	struct xe_vm *vm;
@@ -1661,9 +1661,10 @@ struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
 	vm->xe = xe;
 
 	vm->size = 1ull << xe->info.va_bits;
-
 	vm->flags = flags;
 
+	if (xef)
+		vm->xef = xe_file_get(xef);
 	/**
 	 * GSC VMs are kernel-owned, only used for PXP ops and can sometimes be
 	 * manipulated under the PXP mutex. However, the PXP mutex can be taken
@@ -1814,6 +1815,8 @@ struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
 	for_each_tile(tile, xe, id)
 		xe_range_fence_tree_fini(&vm->rftree[id]);
 	ttm_lru_bulk_move_fini(&xe->ttm, &vm->lru_bulk_move);
+	if (vm->xef)
+		xe_file_put(vm->xef);
 	kfree(vm);
 	if (flags & XE_VM_FLAG_LR_MODE)
 		xe_pm_runtime_put(xe);
@@ -2097,7 +2100,7 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
 	if (args->flags & DRM_XE_VM_CREATE_FLAG_FAULT_MODE)
 		flags |= XE_VM_FLAG_FAULT_MODE;
 
-	vm = xe_vm_create(xe, flags);
+	vm = xe_vm_create(xe, flags, xef);
 	if (IS_ERR(vm))
 		return PTR_ERR(vm);
 
@@ -2113,8 +2116,6 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
 		vm->usm.asid = asid;
 	}
 
-	vm->xef = xe_file_get(xef);
-
 	/* Record BO memory for VM pagetable created against client */
 	for_each_tile(tile, xe, id)
 		if (vm->pt_root[id])

drivers/gpu/drm/xe/xe_vm.h

@@ -26,7 +26,7 @@ struct xe_sync_entry;
 struct xe_svm_range;
 struct drm_exec;
 
-struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags);
+struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags, struct xe_file *xef);
 
 struct xe_vm *xe_vm_lookup(struct xe_file *xef, u32 id);
 int xe_vma_cmp_vma_cb(const void *key, const struct rb_node *node);