41 struct kcov {  struct
229 static void kcov_get(struct kcov *kcov)  in kcov_get()  argument
231 	atomic_inc(&kcov->refcount);  in kcov_get()
234 static void kcov_put(struct kcov *kcov)  in kcov_put()  argument
236 	if (atomic_dec_and_test(&kcov->refcount)) {  in kcov_put()
237 		vfree(kcov->area);  in kcov_put()
238 		kfree(kcov);  in kcov_put()
248 	t->kcov = NULL;  in kcov_task_init()
253 	struct kcov *kcov;  in kcov_task_exit()  local
255 	kcov = t->kcov;  in kcov_task_exit()
256 	if (kcov == NULL)  in kcov_task_exit()
258 	spin_lock(&kcov->lock);  in kcov_task_exit()
259 	if (WARN_ON(kcov->t != t)) {  in kcov_task_exit()
260 		spin_unlock(&kcov->lock);  in kcov_task_exit()
265 	kcov->t = NULL;  in kcov_task_exit()
266 	kcov->mode = KCOV_MODE_INIT;  in kcov_task_exit()
267 	spin_unlock(&kcov->lock);  in kcov_task_exit()
268 	kcov_put(kcov);  in kcov_task_exit()
275 	struct kcov *kcov = vma->vm_file->private_data;  in kcov_mmap()  local
283 	spin_lock(&kcov->lock);  in kcov_mmap()
284 	size = kcov->size * sizeof(unsigned long);  in kcov_mmap()
285 	if (kcov->mode != KCOV_MODE_INIT || vma->vm_pgoff != 0 ||  in kcov_mmap()
290 	if (!kcov->area) {  in kcov_mmap()
291 		kcov->area = area;  in kcov_mmap()
293 		spin_unlock(&kcov->lock);  in kcov_mmap()
295 			page = vmalloc_to_page(kcov->area + off);  in kcov_mmap()
302 	spin_unlock(&kcov->lock);  in kcov_mmap()
309 	struct kcov *kcov;  in kcov_open()  local
311 	kcov = kzalloc(sizeof(*kcov), GFP_KERNEL);  in kcov_open()
312 	if (!kcov)  in kcov_open()
314 	kcov->mode = KCOV_MODE_DISABLED;  in kcov_open()
315 	atomic_set(&kcov->refcount, 1);  in kcov_open()
316 	spin_lock_init(&kcov->lock);  in kcov_open()
317 	filep->private_data = kcov;  in kcov_open()
332 static void kcov_fault_in_area(struct kcov *kcov)  in kcov_fault_in_area()  argument
335 	unsigned long *area = kcov->area;  in kcov_fault_in_area()
338 	for (offset = 0; offset < kcov->size; offset += stride)  in kcov_fault_in_area()
342 static int kcov_ioctl_locked(struct kcov *kcov, unsigned int cmd,  in kcov_ioctl_locked()  argument
354 		if (kcov->mode != KCOV_MODE_DISABLED)  in kcov_ioctl_locked()
364 		kcov->size = size;  in kcov_ioctl_locked()
365 		kcov->mode = KCOV_MODE_INIT;  in kcov_ioctl_locked()
375 		if (kcov->mode != KCOV_MODE_INIT || !kcov->area)  in kcov_ioctl_locked()
378 		if (kcov->t != NULL || t->kcov != NULL)  in kcov_ioctl_locked()
381 			kcov->mode = KCOV_MODE_TRACE_PC;  in kcov_ioctl_locked()
384 			kcov->mode = KCOV_MODE_TRACE_CMP;  in kcov_ioctl_locked()
390 		kcov_fault_in_area(kcov);  in kcov_ioctl_locked()
392 		t->kcov_size = kcov->size;  in kcov_ioctl_locked()
393 		t->kcov_area = kcov->area;  in kcov_ioctl_locked()
396 		WRITE_ONCE(t->kcov_mode, kcov->mode);  in kcov_ioctl_locked()
397 		t->kcov = kcov;  in kcov_ioctl_locked()
398 		kcov->t = t;  in kcov_ioctl_locked()
400 		kcov_get(kcov);  in kcov_ioctl_locked()
405 		if (unused != 0 || current->kcov != kcov)  in kcov_ioctl_locked()
408 		if (WARN_ON(kcov->t != t))  in kcov_ioctl_locked()
411 		kcov->t = NULL;  in kcov_ioctl_locked()
412 		kcov->mode = KCOV_MODE_INIT;  in kcov_ioctl_locked()
413 		kcov_put(kcov);  in kcov_ioctl_locked()
422 	struct kcov *kcov;  in kcov_ioctl()  local
425 	kcov = filep->private_data;  in kcov_ioctl()
426 	spin_lock(&kcov->lock);  in kcov_ioctl()
427 	res = kcov_ioctl_locked(kcov, cmd, arg);  in kcov_ioctl()
428 	spin_unlock(&kcov->lock);  in kcov_ioctl()