// SPDX-License-Identifier: GPL-2.0/* * KUnit userspace memory allocation resource management. */#include <kunit/resource.h>#include <kunit/test.h>#include <linux/kthread.h>#include <linux/mm.h> struct kunit_vm_mmap_resource {	unsigned long addr;	size_t size;}; /* vm_mmap() arguments */struct kunit_vm_mmap_params {	struct file *file;	unsigned long addr;	unsigned long len;	unsigned long prot;	unsigned long flag;	unsigned long offset;}; /* Create and attach a new mm if it doesn't already exist. */static int kunit_attach_mm(void){	struct mm_struct *mm; 	if (current->mm)		return 0; 	/* arch_pick_mmap_layout() is only sane with MMU systems. */	if (!IS_ENABLED(CONFIG_MMU))		return -EINVAL; 	mm = mm_alloc();	if (!mm)		return -ENOMEM; 	/* Define the task size. */	mm->task_size = TASK_SIZE; 	/* Make sure we can allocate new VMAs. */	arch_pick_mmap_layout(mm, &current->signal->rlim[RLIMIT_STACK]); 	/* Attach the mm. It will be cleaned up when the process dies. */	kthread_use_mm(mm); 	return 0;} static int kunit_vm_mmap_init(struct kunit_resource *res, void *context){	struct kunit_vm_mmap_params *p = context;	struct kunit_vm_mmap_resource vres;	int ret; 	ret = kunit_attach_mm();	if (ret)		return ret; 	vres.size = p->len;	vres.addr = vm_mmap(p->file, p->addr, p->len, p->prot, p->flag, p->offset);	if (!vres.addr)		return -ENOMEM;	res->data = kmemdup(&vres, sizeof(vres), GFP_KERNEL);	if (!res->data) {		vm_munmap(vres.addr, vres.size);		return -ENOMEM;	} 	return 0;} static void kunit_vm_mmap_free(struct kunit_resource *res){	struct kunit_vm_mmap_resource *vres = res->data; 	/*	 * Since this is executed from the test monitoring process,	 * the test's mm has already been torn down. We don't need	 * to run vm_munmap(vres->addr, vres->size), only clean up	 * the vres.	 */ 	kfree(vres);	res->data = NULL;} unsigned long kunit_vm_mmap(struct kunit *test, struct file *file,			    unsigned long addr, unsigned long len,			    unsigned long prot, unsigned long flag,			    unsigned long offset){	struct kunit_vm_mmap_params params = {		.file = file,		.addr = addr,		.len = len,		.prot = prot,		.flag = flag,		.offset = offset,	};	struct kunit_vm_mmap_resource *vres; 	vres = kunit_alloc_resource(test,				    kunit_vm_mmap_init,				    kunit_vm_mmap_free,				    GFP_KERNEL,				    &params);	if (vres)		return vres->addr;	return 0;}EXPORT_SYMBOL_GPL(kunit_vm_mmap); MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING);