From patchwork Thu Oct 26 20:01:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: andrey.konovalov@linux.dev X-Patchwork-Id: 738638 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 556003C078 for ; Thu, 26 Oct 2023 20:09:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Q6YJK2jt" X-Greylist: delayed 486 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 26 Oct 2023 13:09:31 PDT Received: from out-174.mta0.migadu.com (out-174.mta0.migadu.com [91.218.175.174]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B84EE129 for ; Thu, 26 Oct 2023 13:09:31 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1698350482; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=w9sbKYXZtIyf/ohQE3Edg07I3no4RCuR4cZPauSieZc=; b=Q6YJK2jt8aNtYlz8aXpbXEWd2kqMpPtQi5xuwpIHAqyuf9aFF60iI469yR9sXN+U5jAsl1 Mtp7c9Vc5whZ4u38LKe46DBzYaXVhRTQQCFXcC/gDZVPwZarUGe2TcuOM0l9txxgRMmVIq drqS5ay+gubC+PaR89dnjZTdhkwB61U= From: andrey.konovalov@linux.dev To: Greg Kroah-Hartman Cc: Andrey Konovalov , Alan Stern , Felipe Balbi , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/3] usb: raw-gadget: properly handle interrupted requests Date: Thu, 26 Oct 2023 22:01:12 +0200 Message-Id: <0db45b1d7cc466e3d4d1ab353f61d63c977fbbc5.1698350424.git.andreyknvl@gmail.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT From: Andrey Konovalov Currently, if a USB request that was queued by Raw Gadget is interrupted (via a signal), wait_for_completion_interruptible returns -ERESTARTSYS. Raw Gadget then attempts to propagate this value to userspace as a return value from its ioctls. However, when -ERESTARTSYS is returned by a syscall handler, the kernel internally restarts the syscall. This doesn't allow userspace applications to interrupt requests queued by Raw Gadget (which is required when the emulated device is asked to switch altsettings). It also violates the implied interface of Raw Gadget that a single ioctl must only queue a single USB request. Instead, make Raw Gadget do what GadgetFS does: check whether the request was interrupted (dequeued with status == -ECONNRESET) and report -EINTR to userspace. Fixes: f2c2e717642c ("usb: gadget: add raw-gadget interface") Signed-off-by: Andrey Konovalov --- drivers/usb/gadget/legacy/raw_gadget.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c index b9ecc55a2ce2..ce9e87f84911 100644 --- a/drivers/usb/gadget/legacy/raw_gadget.c +++ b/drivers/usb/gadget/legacy/raw_gadget.c @@ -674,12 +674,12 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io, if (WARN_ON(in && dev->ep0_out_pending)) { ret = -ENODEV; dev->state = STATE_DEV_FAILED; - goto out_done; + goto out_unlock; } if (WARN_ON(!in && dev->ep0_in_pending)) { ret = -ENODEV; dev->state = STATE_DEV_FAILED; - goto out_done; + goto out_unlock; } dev->req->buf = data; @@ -694,7 +694,7 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io, "fail, usb_ep_queue returned %d\n", ret); spin_lock_irqsave(&dev->lock, flags); dev->state = STATE_DEV_FAILED; - goto out_done; + goto out_queue_failed; } ret = wait_for_completion_interruptible(&dev->ep0_done); @@ -703,13 +703,16 @@ static int raw_process_ep0_io(struct raw_dev *dev, struct usb_raw_ep_io *io, usb_ep_dequeue(dev->gadget->ep0, dev->req); wait_for_completion(&dev->ep0_done); spin_lock_irqsave(&dev->lock, flags); - goto out_done; + if (dev->ep0_status == -ECONNRESET) + dev->ep0_status = -EINTR; + goto out_interrupted; } spin_lock_irqsave(&dev->lock, flags); - ret = dev->ep0_status; -out_done: +out_interrupted: + ret = dev->ep0_status; +out_queue_failed: dev->ep0_urb_queued = false; out_unlock: spin_unlock_irqrestore(&dev->lock, flags); @@ -1078,7 +1081,7 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io, "fail, usb_ep_queue returned %d\n", ret); spin_lock_irqsave(&dev->lock, flags); dev->state = STATE_DEV_FAILED; - goto out_done; + goto out_queue_failed; } ret = wait_for_completion_interruptible(&done); @@ -1087,13 +1090,16 @@ static int raw_process_ep_io(struct raw_dev *dev, struct usb_raw_ep_io *io, usb_ep_dequeue(ep->ep, ep->req); wait_for_completion(&done); spin_lock_irqsave(&dev->lock, flags); - goto out_done; + if (ep->status == -ECONNRESET) + ep->status = -EINTR; + goto out_interrupted; } spin_lock_irqsave(&dev->lock, flags); - ret = ep->status; -out_done: +out_interrupted: + ret = ep->status; +out_queue_failed: ep->urb_queued = false; out_unlock: spin_unlock_irqrestore(&dev->lock, flags); From patchwork Thu Oct 26 20:01:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: andrey.konovalov@linux.dev X-Patchwork-Id: 738637 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BAE393C6B2 for ; Thu, 26 Oct 2023 20:09:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="VGYbP43i" X-Greylist: delayed 487 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 26 Oct 2023 13:09:31 PDT Received: from out-189.mta0.migadu.com (out-189.mta0.migadu.com [IPv6:2001:41d0:1004:224b::bd]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CBFF51AC for ; Thu, 26 Oct 2023 13:09:31 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1698350483; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rChh14RoKqHyNTtLO4oEGTir1WUGyXt9ry5A85Vdpuk=; b=VGYbP43i8J4IsipMVD+zeMt0fHoJnBYRw/yKfBwEDSHLF165mZk657fUGAW6Z6z7F1+H0W L/HFADJLtTzn+GsE1YxiJyBXy1pXgyb20osxW+e5iFmf36OGuuCM7hUZ61svAzlchTfN6U PZAeo7JpU0FDob/uVbpy0QFzmiAh050= From: andrey.konovalov@linux.dev To: Greg Kroah-Hartman Cc: Andrey Konovalov , Alan Stern , Felipe Balbi , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/3] usb: raw-gadget: report suspend, resume, reset, and disconnect events Date: Thu, 26 Oct 2023 22:01:14 +0200 Message-Id: In-Reply-To: <0db45b1d7cc466e3d4d1ab353f61d63c977fbbc5.1698350424.git.andreyknvl@gmail.com> References: <0db45b1d7cc466e3d4d1ab353f61d63c977fbbc5.1698350424.git.andreyknvl@gmail.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT From: Andrey Konovalov Update USB_RAW_IOCTL_EVENT_FETCH to also report suspend, resume, reset, and disconnect events. This allows the code that emulates a USB device via Raw Gadget to handle these events. For example, the device can restart enumeration when it gets reset. Also do not print a WARNING when the event queue overflows. With these new events being queued, the queue might overflow if the device emulation code stops fetching events. Also print debug messages when a non-control event is received. Signed-off-by: Andrey Konovalov --- Changes v1->v2: - Don't print another error message if event queue overflows: each caller already prints one if event queueing fails. --- drivers/usb/gadget/legacy/raw_gadget.c | 52 ++++++++++++++++++++++---- include/uapi/linux/usb/raw_gadget.h | 14 ++++++- 2 files changed, 56 insertions(+), 10 deletions(-) diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c index daac1f078516..399fca32a8ac 100644 --- a/drivers/usb/gadget/legacy/raw_gadget.c +++ b/drivers/usb/gadget/legacy/raw_gadget.c @@ -65,7 +65,7 @@ static int raw_event_queue_add(struct raw_event_queue *queue, struct usb_raw_event *event; spin_lock_irqsave(&queue->lock, flags); - if (WARN_ON(queue->size >= RAW_EVENT_QUEUE_SIZE)) { + if (queue->size >= RAW_EVENT_QUEUE_SIZE) { spin_unlock_irqrestore(&queue->lock, flags); return -ENOMEM; } @@ -311,9 +311,10 @@ static int gadget_bind(struct usb_gadget *gadget, dev->eps_num = i; spin_unlock_irqrestore(&dev->lock, flags); + dev_dbg(&gadget->dev, "gadget connected\n"); ret = raw_queue_event(dev, USB_RAW_EVENT_CONNECT, 0, NULL); if (ret < 0) { - dev_err(&gadget->dev, "failed to queue event\n"); + dev_err(&gadget->dev, "failed to queue connect event\n"); set_gadget_data(gadget, NULL); return ret; } @@ -358,7 +359,7 @@ static int gadget_setup(struct usb_gadget *gadget, ret = raw_queue_event(dev, USB_RAW_EVENT_CONTROL, sizeof(*ctrl), ctrl); if (ret < 0) - dev_err(&gadget->dev, "failed to queue event\n"); + dev_err(&gadget->dev, "failed to queue control event\n"); goto out; out_unlock: @@ -377,11 +378,46 @@ static int gadget_setup(struct usb_gadget *gadget, return ret; } -/* These are currently unused but present in case UDC driver requires them. */ -static void gadget_disconnect(struct usb_gadget *gadget) { } -static void gadget_suspend(struct usb_gadget *gadget) { } -static void gadget_resume(struct usb_gadget *gadget) { } -static void gadget_reset(struct usb_gadget *gadget) { } +static void gadget_disconnect(struct usb_gadget *gadget) +{ + struct raw_dev *dev = get_gadget_data(gadget); + int ret; + + dev_dbg(&gadget->dev, "gadget disconnected\n"); + ret = raw_queue_event(dev, USB_RAW_EVENT_DISCONNECT, 0, NULL); + if (ret < 0) + dev_err(&gadget->dev, "failed to queue disconnect event\n"); +} +static void gadget_suspend(struct usb_gadget *gadget) +{ + struct raw_dev *dev = get_gadget_data(gadget); + int ret; + + dev_dbg(&gadget->dev, "gadget suspended\n"); + ret = raw_queue_event(dev, USB_RAW_EVENT_SUSPEND, 0, NULL); + if (ret < 0) + dev_err(&gadget->dev, "failed to queue suspend event\n"); +} +static void gadget_resume(struct usb_gadget *gadget) +{ + struct raw_dev *dev = get_gadget_data(gadget); + int ret; + + dev_dbg(&gadget->dev, "gadget resumed\n"); + ret = raw_queue_event(dev, USB_RAW_EVENT_RESUME, 0, NULL); + if (ret < 0) + dev_err(&gadget->dev, "failed to queue resume event\n"); +} +static void gadget_reset(struct usb_gadget *gadget) +{ + struct raw_dev *dev = get_gadget_data(gadget); + int ret; + + dev_dbg(&gadget->dev, "gadget reset\n"); + ret = raw_queue_event(dev, USB_RAW_EVENT_RESET, 0, NULL); + if (ret < 0) + dev_err(&gadget->dev, "failed to queue reset event\n"); +} /*----------------------------------------------------------------------*/ diff --git a/include/uapi/linux/usb/raw_gadget.h b/include/uapi/linux/usb/raw_gadget.h index c7d2199134d7..f0224a8dc858 100644 --- a/include/uapi/linux/usb/raw_gadget.h +++ b/include/uapi/linux/usb/raw_gadget.h @@ -44,6 +44,16 @@ enum usb_raw_event_type { /* This event is queued when a new control request arrived to ep0. */ USB_RAW_EVENT_CONTROL = 2, + /* + * These events are queued when the gadget driver is suspended, + * resumed, reset, or disconnected. Note that some UDCs (e.g. dwc2) + * report a disconnect event instead of a reset. + */ + USB_RAW_EVENT_SUSPEND = 3, + USB_RAW_EVENT_RESUME = 4, + USB_RAW_EVENT_RESET = 5, + USB_RAW_EVENT_DISCONNECT = 6, + /* The list might grow in the future. */ }; @@ -54,8 +64,8 @@ enum usb_raw_event_type { * actual length of the fetched event data. * @data: A buffer to store the fetched event data. * - * Currently the fetched data buffer is empty for USB_RAW_EVENT_CONNECT, - * and contains struct usb_ctrlrequest for USB_RAW_EVENT_CONTROL. + * The fetched event data buffer contains struct usb_ctrlrequest for + * USB_RAW_EVENT_CONTROL and is empty for other events. */ struct usb_raw_event { __u32 type;