usb: f_fs: refactor ffs_epfile_io (ae76e134) · Commits · e / devices / android_kernel_oneplus_sm8150

drivers/usb/gadget/function/f_fs.c

+58 −69

Original line number	Original line	Diff line number	Diff line
	@@ -684,6 +684,7 @@ static void ffs_epfile_async_io_complete(struct usb_ep *_ep,
	static ssize_t ffs_epfile_io(struct file file, struct ffs_io_data io_data)		static ssize_t ffs_epfile_io(struct file file, struct ffs_io_data io_data)
	{		{
	struct ffs_epfile *epfile = file->private_data;		struct ffs_epfile *epfile = file->private_data;
			struct usb_request *req;
	struct ffs_ep *ep;		struct ffs_ep *ep;
	char *data = NULL;		char *data = NULL;
	ssize_t ret, data_len = -EINVAL;		ssize_t ret, data_len = -EINVAL;
	@@ -713,7 +714,8 @@ static ssize_t ffs_epfile_io(struct file file, struct ffs_io_data io_data)
	if (!halt) {		if (!halt) {
	/*		/*
	* if we _do_ wait above, the epfile->ffs->gadget might be NULL		* if we _do_ wait above, the epfile->ffs->gadget might be NULL
	* before the waiting completes, so do not assign to 'gadget' earlier		* before the waiting completes, so do not assign to 'gadget'
			* earlier
	*/		*/
	struct usb_gadget *gadget = epfile->ffs->gadget;		struct usb_gadget *gadget = epfile->ffs->gadget;
	size_t copied;		size_t copied;
	@@ -755,17 +757,12 @@ static ssize_t ffs_epfile_io(struct file file, struct ffs_io_data io_data)
	if (epfile->ep != ep) {		if (epfile->ep != ep) {
	/* In the meantime, endpoint got disabled or changed. */		/* In the meantime, endpoint got disabled or changed. */
	ret = -ESHUTDOWN;		ret = -ESHUTDOWN;
	goto error_lock;
	} else if (halt) {		} else if (halt) {
	/* Halt */		/* Halt */
	if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))		if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
	usb_ep_set_halt(ep->ep);		usb_ep_set_halt(ep->ep);
	spin_unlock_irq(&epfile->ffs->eps_lock);
	ret = -EBADMSG;		ret = -EBADMSG;
	} else {		} else if (unlikely(data_len == -EINVAL)) {
	/* Fire the request */
	struct usb_request *req;

	/*		/*
	* Sanity Check: even though data_len can't be used		* Sanity Check: even though data_len can't be used
	* uninitialized at the time I write this comment, some		* uninitialized at the time I write this comment, some
	@@ -777,39 +774,9 @@ static ssize_t ffs_epfile_io(struct file file, struct ffs_io_data io_data)
	* For such reason, we're adding this redundant sanity check		* For such reason, we're adding this redundant sanity check
	* here.		* here.
	*/		*/
	if (unlikely(data_len == -EINVAL)) {
	WARN(1, "%s: data_len == -EINVAL\n", __func__);		WARN(1, "%s: data_len == -EINVAL\n", __func__);
	ret = -EINVAL;		ret = -EINVAL;
	goto error_lock;		} else if (!io_data->aio) {
	}

	if (io_data->aio) {
	req = usb_ep_alloc_request(ep->ep, GFP_KERNEL);
	if (unlikely(!req)) {
	ret = -ENOMEM;
	goto error_lock;
	}

	req->buf = data;
	req->length = data_len;

	io_data->buf = data;
	io_data->ep = ep->ep;
	io_data->req = req;
	io_data->ffs = epfile->ffs;

	req->context = io_data;
	req->complete = ffs_epfile_async_io_complete;

	ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
	if (unlikely(ret)) {
	usb_ep_free_request(ep->ep, req);
	goto error_lock;
	}
	ret = -EIOCBQUEUED;

	spin_unlock_irq(&epfile->ffs->eps_lock);
	} else {
	DECLARE_COMPLETION_ONSTACK(done);		DECLARE_COMPLETION_ONSTACK(done);

	req = ep->req;		req = ep->req;
	@@ -820,22 +787,22 @@ static ssize_t ffs_epfile_io(struct file file, struct ffs_io_data io_data)
	req->complete = ffs_epfile_io_complete;		req->complete = ffs_epfile_io_complete;

	ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);		ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
			if (unlikely(ret < 0))
			goto error_lock;

	spin_unlock_irq(&epfile->ffs->eps_lock);		spin_unlock_irq(&epfile->ffs->eps_lock);

	if (unlikely(ret < 0)) {		if (unlikely(wait_for_completion_interruptible(&done))) {
	/* nop */
	} else if (unlikely(
	wait_for_completion_interruptible(&done))) {
	ret = -EINTR;		ret = -EINTR;
	usb_ep_dequeue(ep->ep, req);		usb_ep_dequeue(ep->ep, req);
	} else {		goto error_mutex;
			}

	/*		/*
	* XXX We may end up silently droping data		* XXX We may end up silently droping data here. Since data_len
	* here. Since data_len (i.e. req->length) may		* (i.e. req->length) may be bigger than len (after being
	* be bigger than len (after being rounded up		* rounded up to maxpacketsize), we may end up with more data
	* to maxpacketsize), we may end up with more		* then user space has space for.
	* data then user space has space for.
	*/		*/
	ret = ep->status;		ret = ep->status;
	if (io_data->read && ret > 0) {		if (io_data->read && ret > 0) {
	@@ -843,16 +810,38 @@ static ssize_t ffs_epfile_io(struct file file, struct ffs_io_data io_data)
	if (!ret)		if (!ret)
	ret = -EFAULT;		ret = -EFAULT;
	}		}
	}		goto error_mutex;
	kfree(data);		} else if (!(req = usb_ep_alloc_request(ep->ep, GFP_KERNEL))) {
	}		ret = -ENOMEM;
			} else {
			req->buf = data;
			req->length = data_len;

			io_data->buf = data;
			io_data->ep = ep->ep;
			io_data->req = req;
			io_data->ffs = epfile->ffs;

			req->context = io_data;
			req->complete = ffs_epfile_async_io_complete;

			ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
			if (unlikely(ret)) {
			usb_ep_free_request(ep->ep, req);
			goto error_lock;
	}		}

	mutex_unlock(&epfile->mutex);		ret = -EIOCBQUEUED;
	return ret;		/*
			* Do not kfree the buffer in this function. It will be freed
			* by ffs_user_copy_worker.
			*/
			data = NULL;
			}

	error_lock:		error_lock:
	spin_unlock_irq(&epfile->ffs->eps_lock);		spin_unlock_irq(&epfile->ffs->eps_lock);
			error_mutex:
	mutex_unlock(&epfile->mutex);		mutex_unlock(&epfile->mutex);
	error:		error:
	kfree(data);		kfree(data);