From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751874AbdCRTAo (ORCPT ); Sat, 18 Mar 2017 15:00:44 -0400 Received: from mout.gmx.net ([212.227.17.21]:53118 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751695AbdCRTAk (ORCPT ); Sat, 18 Mar 2017 15:00:40 -0400 From: Tobias Herzog To: oneukum@suse.com Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/4] cdc-acm: reassemble fragmented notifications Date: Sat, 18 Mar 2017 19:52:36 +0100 Message-Id: <1489863159-10972-2-git-send-email-t-herzog@gmx.de> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1489863159-10972-1-git-send-email-t-herzog@gmx.de> References: <1479118868.21146.4.camel@suse.com> <1489863159-10972-1-git-send-email-t-herzog@gmx.de> X-Provags-ID: V03:K0:ms42/FHs7TjyuNzNhLd/KZ/Vlc5pjWG3Ahzzo4mDywm35I/MfDl qaEA9zBGI9rhaEpyfAgWqHxm25tjf8Eo9t+kHLH2Ho0zNRNHbVPyByFG1ENc8hzCY+zeUMk e30Jq+09rloUG98BG98BG3Fznnk7DpEITiHE392dAgJu3AgHcf7SEPHlZrk2m0761ajpJK1 Im5wm53NNWyaoZFFG7hyA== X-UI-Out-Filterresults: notjunk:1;V01:K0:VhaLBgkzgCI=:B+Y5MXUQ7/j+pAs49NzPm+ Y7r0nK1zjIEBaMqRSVu1BrdpZWhLul6jd7cAPuF8gA+cBlw3uMb8LM6SydnxYqFLFLLhrzmyR qgY90GJlEObExuVw+V9k5M2gOgyFV6w3xSpeISn6cVQ0C7pAqbtCjJqE1N2N1EcLAWsoJcCUg N4vXKdXchSwV92l1KyZ3e45vezrVdhitHwYS+VHvANS8hZfJehMrv8OdJSHdjmqoqo0mUsv0f wmUYw15kQOa90gyUe/xqa38rEhb8iAaqk09couZr06b1Lx8mzHsakL/1cVLQma1ZxhhPyysqe 4AGlFRPhec4nUBmpo/V5D9Ioj7lsiLIsY3EWvj+VaqmqQkGCVSzIycD2nEk9wTbMsl5r7Bx3o s77IkviDTc1DlokIjmGaXHAAJ2lo2FyI7YlLs20xDoI8eoEXdpkDmZ8TO14yl4pIGzu8NBDu5 b+PiSl5Ym/5zRYRM9cqBsE5edH8fV6SIaBuRbMwF1L++DZTDLfI6vEy1JZ3f0ctB6/2Zr+HUf b8a8PlYiUsZ44atn+xlVrnZmSCkWHOmStd32aoLrwlCAZeayc9V2jKL3EFgCaawqDjq/dZuFm zxDIYcrSlSAqhHONIhrgeDCeVgbtJ/pTa+En2cgQPjgWTQaL1lIfijHnX43beaipIl6ofH1Qy 69VPhEwvv+7un6CAJ6c03Rv30eAMoFHQxAFE+aC06PgN8MUCMG+ddSCreGrpCBoewP0hbOhNU 8Jgphw57euGxKS6bwndjA1MBJt5y4KNxktd7IaXnNz2q+0c916Yt73Lp54Q= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org USB devices may have very limitited 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 | 106 ++++++++++++++++++++++++++++++++------------ drivers/usb/class/cdc-acm.h | 3 ++ 2 files changed, 80 insertions(+), 29 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index e35b150..74acca1 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -282,39 +282,13 @@ 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 = (unsigned char *)(dr + 1); - 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, @@ -363,8 +337,77 @@ static void acm_ctrl_irq(struct urb *urb) __func__, dr->bNotificationType, dr->wIndex, dr->wLength, data[0], data[1]); + } +} + +/* 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; + 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; + } + acm->notification_buffer = + kmalloc(expected_size, GFP_ATOMIC); + if (!acm->notification_buffer) + goto exit; + acm->nb_size = expected_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) @@ -1488,6 +1531,9 @@ 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); @@ -1580,6 +1626,8 @@ 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