From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935030AbdC3UQV (ORCPT ); Thu, 30 Mar 2017 16:16:21 -0400 Received: from mout.gmx.net ([212.227.15.19]:57464 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934813AbdC3UPh (ORCPT ); Thu, 30 Mar 2017 16:15:37 -0400 From: Tobias Herzog To: oneukum@suse.com Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v3 2/4] cdc-acm: reassemble fragmented notifications Date: Thu, 30 Mar 2017 22:15:11 +0200 Message-Id: <1490904913-3222-3-git-send-email-t-herzog@gmx.de> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1490904913-3222-1-git-send-email-t-herzog@gmx.de> References: <1479118868.21146.4.camel@suse.com> <1490904913-3222-1-git-send-email-t-herzog@gmx.de> X-Provags-ID: V03:K0:764+66LVvwJL3Ypo3/kTbT6ES2ojuywMwO3w/nU3TMW9LKbbTwD p+0e9rQNKIC66PPBKcxdH4np/0o97/iOApVKZ3fNfQQE/1UzhK+MJlI6/91Be8bLKLVMfiO NKifNep7odw+xyaSnaFAq7aXOt5BXzFcaaX18L+Imrd+1VPDqDe1nmGwNn7dfTHehyUVIWK izHwkL7zUW5/VPMqqKH+A== X-UI-Out-Filterresults: notjunk:1;V01:K0:LB3zj/sck/U=:IyFmQ7rT9lmYtwxLyhaqar UCPCbuv3PsFNg4mLznrk2X6bItChDcJKKDSKLnMnTSck/YbJkPalIw/NOwJDw6Lztxofx61Kl WxaYARR7yLqX0KGfisokjqeigXpL0sdq/RkxJGMQgI3HXP+1HYGq8LjBHTdLaLyIO8WG3o6y3 H1b2ydsFQNndBb0s0iV3pb8Og8AFKZiClCEOIkQavEXuOgBbobfrIjgrZ7j72sB2XglRgMESU LABBD57TjsRD4m5rrRn95qiHFt7LihcOss3qP3z2moi6mDtQD441Iet0fbQxb8Sj6LfPxQgwB LePVnBU7o25DuDHsR9mwEggSURI+YHAWn1XDqdPmkv+d6i6wG9FATQKw0k9nvqY5YusqSJOUm oVcXXGRN7X/k/3H2QUYTSvSG/zjgDXabuWpmCNrtJjV6v9g6RcwYYqBa7GU/hRhaJ5dcfaFrM vn1yJkrI+twYITXKBv5VY321aT3qKbFwBCvpKiR4HljBuao3iMpdYEUTxiwvrLWTICwkIv2AB cKwSKy7HIpUMjeVkTQLBuZzqkQ7yifxQ+WgE5ae9IDnjubnlNzYDHx4qdhSF6ePbIWCQTkBkQ in3E29mJ8Nvs+/7mEKya4cV9xuv0m8yxgS2XWxJMSI7HkQd/mk3StoBaUUlUfEoRufV1g/D/h yt8YDrOg3/08vl5Ep4ZqPHJoBbO1LlnnIPJfZs+W41xX7Ikf8dU1gr2m6WTT6rs54GBU4ZM2h K2PyoFG1N3kpU/hXR3ZxWnBotBJ1VxawYOSY7yCL1LJXO+RlxutFwslhQWc= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org USB devices may have very limited endpoint packet sizes, so that notifications can not be transferred within one single usb packet. Reassembling of multiple packages may be necessary. Signed-off-by: Tobias Herzog --- drivers/usb/class/cdc-acm.c | 112 ++++++++++++++++++++++++++++++++------------ drivers/usb/class/cdc-acm.h | 3 ++ 2 files changed, 86 insertions(+), 29 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index f554e2f..58efa15 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include #include @@ -282,39 +283,13 @@ static DEVICE_ATTR(iCountryCodeRelDate, S_IRUGO, show_country_rel_date, NULL); * Interrupt handlers for various ACM device responses */ -/* control interface reports status changes with "interrupt" transfers */ -static void acm_ctrl_irq(struct urb *urb) +static void acm_process_notification(struct acm *acm, unsigned char *buf) { - struct acm *acm = urb->context; - struct usb_cdc_notification *dr = urb->transfer_buffer; - unsigned char *data; int newctrl; int difference; - int retval; - int status = urb->status; - - switch (status) { - case 0: - /* success */ - break; - case -ECONNRESET: - case -ENOENT: - case -ESHUTDOWN: - /* this urb is terminated, clean up */ - dev_dbg(&acm->control->dev, - "%s - urb shutting down with status: %d\n", - __func__, status); - return; - default: - dev_dbg(&acm->control->dev, - "%s - nonzero urb status received: %d\n", - __func__, status); - goto exit; - } + struct usb_cdc_notification *dr = (struct usb_cdc_notification *)buf; + unsigned char *data = buf + sizeof(struct usb_cdc_notification); - usb_mark_last_busy(acm->dev); - - data = (unsigned char *)(dr + 1); switch (dr->bNotificationType) { case USB_CDC_NOTIFY_NETWORK_CONNECTION: dev_dbg(&acm->control->dev, @@ -367,9 +342,83 @@ static void acm_ctrl_irq(struct urb *urb) "%s - unknown notification %d received: index %d len %d\n", __func__, dr->bNotificationType, dr->wIndex, dr->wLength); + } +} +/* control interface reports status changes with "interrupt" transfers */ +static void acm_ctrl_irq(struct urb *urb) +{ + struct acm *acm = urb->context; + struct usb_cdc_notification *dr = urb->transfer_buffer; + unsigned int current_size = urb->actual_length; + unsigned int expected_size, copy_size, alloc_size; + int retval; + int status = urb->status; + + switch (status) { + case 0: + /* success */ break; + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + /* this urb is terminated, clean up */ + acm->nb_index = 0; + dev_dbg(&acm->control->dev, + "%s - urb shutting down with status: %d\n", + __func__, status); + return; + default: + dev_dbg(&acm->control->dev, + "%s - nonzero urb status received: %d\n", + __func__, status); + goto exit; + } + + usb_mark_last_busy(acm->dev); + + if (acm->nb_index) + dr = (struct usb_cdc_notification *)acm->notification_buffer; + + /* size = notification-header + (optional) data */ + expected_size = sizeof(struct usb_cdc_notification) + + le16_to_cpu(dr->wLength); + + if (current_size < expected_size) { + /* notification is transmitted fragmented, reassemble */ + if (acm->nb_size < expected_size) { + if (acm->nb_size) { + kfree(acm->notification_buffer); + acm->nb_size = 0; + } + alloc_size = roundup_pow_of_two(expected_size); + /* + * kmalloc ensures a valid notification_buffer after a + * use of kfree in case the previous allocation was too + * small. Final freeing is done on disconnect. + */ + acm->notification_buffer = + kmalloc(alloc_size, GFP_ATOMIC); + if (!acm->notification_buffer) + goto exit; + acm->nb_size = alloc_size; + } + + copy_size = min(current_size, + expected_size - acm->nb_index); + + memcpy(&acm->notification_buffer[acm->nb_index], + urb->transfer_buffer, copy_size); + acm->nb_index += copy_size; + current_size = acm->nb_index; } + + if (current_size >= expected_size) { + /* notification complete */ + acm_process_notification(acm, (unsigned char *)dr); + acm->nb_index = 0; + } + exit: retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval && retval != -EPERM) @@ -1493,6 +1542,9 @@ static int acm_probe(struct usb_interface *intf, epctrl->bInterval ? epctrl->bInterval : 16); acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; acm->ctrlurb->transfer_dma = acm->ctrl_dma; + acm->notification_buffer = NULL; + acm->nb_index = 0; + acm->nb_size = 0; dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor); @@ -1585,6 +1637,8 @@ static void acm_disconnect(struct usb_interface *intf) usb_free_coherent(acm->dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma); acm_read_buffers_free(acm); + kfree(acm->notification_buffer); + if (!acm->combined_interfaces) usb_driver_release_interface(&acm_driver, intf == acm->control ? acm->data : acm->control); diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index c980f11..b519138 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -98,6 +98,9 @@ struct acm { struct acm_wb *putbuffer; /* for acm_tty_put_char() */ int rx_buflimit; spinlock_t read_lock; + u8 *notification_buffer; /* to reassemble fragmented notifications */ + unsigned int nb_index; + unsigned int nb_size; int write_used; /* number of non-empty write buffers */ int transmitting; spinlock_t write_lock; -- 2.1.4