					       void __user *arg)
	__must_hold(&ctx->uring_lock)
{
	struct io_tctx_node *node;
	struct io_uring_task *tctx = NULL;
	struct io_sq_data *sqd = NULL;
	__u32 new_count[2];
	int i, ret;

	if (copy_from_user(new_count, arg, sizeof(new_count)))
		return -EFAULT;
	for (i = 0; i < ARRAY_SIZE(new_count); i++)
		if (new_count[i] > INT_MAX)
			return -EINVAL;

	if (ctx->flags & IORING_SETUP_SQPOLL) {
		sqd = ctx->sq_data;
		if (sqd) {
			/*
			 * Observe the correct sqd->lock -> ctx->uring_lock
			 * ordering. Fine to drop uring_lock here, we hold
			 * a ref to the ctx.
			 */
			refcount_inc(&sqd->refs);
			mutex_unlock(&ctx->uring_lock);
			mutex_lock(&sqd->lock);
			mutex_lock(&ctx->uring_lock);
			if (sqd->thread)
				tctx = sqd->thread->io_uring;
		}
	} else {
		tctx = current->io_uring;
	}

	BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits));

	for (i = 0; i < ARRAY_SIZE(new_count); i++)
		if (new_count[i])
			ctx->iowq_limits[i] = new_count[i];
	ctx->iowq_limits_set = true;

	if (tctx && tctx->io_wq) {
		ret = io_wq_max_workers(tctx->io_wq, new_count);
		if (ret)
			goto err;
	} else {
		memset(new_count, 0, sizeof(new_count));
	}

	if (sqd) {
		mutex_unlock(&sqd->lock);
		io_put_sq_data(sqd);
	}

	if (copy_to_user(arg, new_count, sizeof(new_count)))
		return -EFAULT;

	/* that's it for SQPOLL, only the SQPOLL task creates requests */
	if (sqd)
		return 0;

	/* now propagate the restriction to all registered users */
	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
		struct io_uring_task *tctx = node->task->io_uring;

		if (WARN_ON_ONCE(!tctx->io_wq))
			continue;

		for (i = 0; i < ARRAY_SIZE(new_count); i++)
			new_count[i] = ctx->iowq_limits[i];
		/* ignore errors, it always returns zero anyway */
		(void)io_wq_max_workers(tctx->io_wq, new_count);
	}
	return 0;
err:
	if (sqd) {
		mutex_unlock(&sqd->lock);
		io_put_sq_data(sqd);
	}
	return ret;