Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756725AbbFPO4r (ORCPT ); Tue, 16 Jun 2015 10:56:47 -0400 Received: from cantor2.suse.de ([195.135.220.15]:55296 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754814AbbFPO4h (ORCPT ); Tue, 16 Jun 2015 10:56:37 -0400 Message-ID: <55803923.3050208@suse.com> Date: Tue, 16 Jun 2015 16:56:35 +0200 From: Juergen Gross User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Greg KH CC: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, konrad.wilk@oracle.com, david.vrabel@citrix.com, boris.ostrovsky@oracle.com, linux-usb@vger.kernel.org Subject: Re: [Patch V3 2/3] usb: Introduce Xen pvUSB frontend (xen hcd) References: <1434465155-8401-1-git-send-email-jgross@suse.com> <1434465155-8401-3-git-send-email-jgross@suse.com> <20150616144514.GA13595@kroah.com> In-Reply-To: <20150616144514.GA13595@kroah.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9630 Lines: 285 On 06/16/2015 04:45 PM, Greg KH wrote: > On Tue, Jun 16, 2015 at 04:32:34PM +0200, Juergen Gross wrote: >> Introduces the Xen pvUSB frontend. With pvUSB it is possible for a Xen >> domU to communicate with a USB device assigned to that domU. The >> communication is all done via the pvUSB backend in a driver domain >> (usually Dom0) which is owner of the physical device. >> >> The pvUSB frontend is a USB hcd for a virtual USB host connector. >> >> The code is taken from the pvUSB implementation in Xen done by Fujitsu >> based on Linux kernel 2.6.18. >> >> Changes from the original version are: >> - port to upstream kernel >> - put all code in just one source file >> - move module to appropriate location in kernel tree >> - adapt to Linux style guide >> - minor code modifications to increase readability >> >> Signed-off-by: Juergen Gross >> --- >> drivers/usb/host/Kconfig | 11 + >> drivers/usb/host/Makefile | 1 + >> drivers/usb/host/xen-hcd.c | 1638 ++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 1650 insertions(+) >> create mode 100644 drivers/usb/host/xen-hcd.c >> >> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig >> index 197a6a3..3361b4b 100644 >> --- a/drivers/usb/host/Kconfig >> +++ b/drivers/usb/host/Kconfig >> @@ -788,3 +788,14 @@ config USB_HCD_TEST_MODE >> This option is of interest only to developers who need to validate >> their USB hardware designs. It is not needed for normal use. If >> unsure, say N. >> + >> +config USB_XEN_HCD >> + tristate "Xen usb virtual host driver" >> + depends on XEN >> + select XEN_XENBUS_FRONTEND >> + help >> + The Xen usb virtual host driver serves as a frontend driver enabling >> + a Xen guest system to access USB Devices passed through to the guest >> + by the Xen host (usually Dom0). >> + Only needed if the kernel is running in a Xen guest and generic >> + access to a USB device is needed. >> diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile >> index 65b0b6a..3779696 100644 >> --- a/drivers/usb/host/Makefile >> +++ b/drivers/usb/host/Makefile >> @@ -75,3 +75,4 @@ obj-$(CONFIG_USB_HCD_SSB) += ssb-hcd.o >> obj-$(CONFIG_USB_FUSBH200_HCD) += fusbh200-hcd.o >> obj-$(CONFIG_USB_FOTG210_HCD) += fotg210-hcd.o >> obj-$(CONFIG_USB_MAX3421_HCD) += max3421-hcd.o >> +obj-$(CONFIG_USB_XEN_HCD) += xen-hcd.o >> diff --git a/drivers/usb/host/xen-hcd.c b/drivers/usb/host/xen-hcd.c >> new file mode 100644 >> index 0000000..9da2856 >> --- /dev/null >> +++ b/drivers/usb/host/xen-hcd.c >> @@ -0,0 +1,1638 @@ >> +/* >> + * xen-hcd.c >> + * >> + * Xen USB Virtual Host Controller driver >> + * >> + * Copyright (C) 2009, FUJITSU LABORATORIES LTD. >> + * Author: Noboru Iwamatsu >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License as published by >> + * the Free Software Foundation; either version 2 of the License, or >> + * (at your option) any later version. >> + * >> + * This program is distributed in the hope that it will be useful, >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >> + * GNU General Public License for more details. >> + * >> + * You should have received a copy of the GNU General Public License >> + * along with this program; if not, see . >> + * >> + * Or, by your choice: >> + * >> + * When distributed separately from the Linux kernel or incorporated into >> + * other software packages, subject to the following license: >> + * >> + * Permission is hereby granted, free of charge, to any person obtaining a copy >> + * of this software and associated documentation files (the "Software"), to >> + * deal in the Software without restriction, including without limitation the >> + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or >> + * sell copies of the Software, and to permit persons to whom the Software is >> + * furnished to do so, subject to the following conditions: >> + * >> + * The above copyright notice and this permission notice shall be included in >> + * all copies or substantial portions of the Software. >> + * >> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR >> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, >> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE >> + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER >> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING >> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER >> + * DEALINGS IN THE SOFTWARE. >> + */ >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +#include >> + >> +/* Private per-URB data */ >> +struct urb_priv { >> + struct list_head list; >> + struct urb *urb; >> + int req_id; /* RING_REQUEST id for submitting */ >> + int unlink_req_id; /* RING_REQUEST id for unlinking */ >> + int status; >> + unsigned unlinked:1; /* dequeued marker */ >> +}; >> + >> +/* virtual roothub port status */ >> +struct rhport_status { >> + __u32 status; >> + unsigned resuming:1; /* in resuming */ >> + unsigned c_connection:1; /* connection changed */ >> + unsigned long timeout; >> +}; >> + >> +/* status of attached device */ >> +struct vdevice_status { >> + int devnum; >> + enum usb_device_state status; >> + enum usb_device_speed speed; >> +}; >> + >> +/* RING request shadow */ >> +struct usb_shadow { >> + struct xenusb_urb_request req; >> + struct urb *urb; >> +}; >> + >> +struct xenhcd_info { >> + /* Virtual Host Controller has 4 urb queues */ >> + struct list_head pending_submit_list; >> + struct list_head pending_unlink_list; >> + struct list_head in_progress_list; >> + struct list_head giveback_waiting_list; >> + >> + spinlock_t lock; >> + >> + /* timer that kick pending and giveback waiting urbs */ >> + struct timer_list watchdog; >> + unsigned long actions; >> + >> + /* virtual root hub */ >> + int rh_numports; >> + struct rhport_status ports[XENUSB_MAX_PORTNR]; >> + struct vdevice_status devices[XENUSB_MAX_PORTNR]; >> + >> + /* Xen related staff */ >> + struct xenbus_device *xbdev; >> + int urb_ring_ref; >> + int conn_ring_ref; >> + struct xenusb_urb_front_ring urb_ring; >> + struct xenusb_conn_front_ring conn_ring; >> + >> + unsigned int evtchn; >> + unsigned int irq; >> + struct usb_shadow shadow[XENUSB_URB_RING_SIZE]; >> + unsigned shadow_free; >> +}; >> + >> +#define GRANT_INVALID_REF 0 >> + >> +#define XENHCD_RING_JIFFIES (HZ/200) >> +#define XENHCD_SCAN_JIFFIES 1 >> + >> +enum xenhcd_timer_action { >> + TIMER_RING_WATCHDOG, >> + TIMER_SCAN_PENDING_URBS, >> +}; >> + >> +static struct kmem_cache *xenhcd_urbp_cachep; >> + >> +static inline struct xenhcd_info *xenhcd_hcd_to_info(struct usb_hcd *hcd) >> +{ >> + return (struct xenhcd_info *)hcd->hcd_priv; >> +} >> + >> +static inline struct usb_hcd *xenhcd_info_to_hcd(struct xenhcd_info *info) >> +{ >> + return container_of((void *)info, struct usb_hcd, hcd_priv); >> +} >> + >> +static inline void xenhcd_timer_action_done(struct xenhcd_info *info, >> + enum xenhcd_timer_action action) >> +{ >> + clear_bit(action, &info->actions); >> +} >> + >> +static void xenhcd_timer_action(struct xenhcd_info *info, >> + enum xenhcd_timer_action action) >> +{ >> + if (timer_pending(&info->watchdog) && >> + test_bit(TIMER_SCAN_PENDING_URBS, &info->actions)) >> + return; >> + >> + if (!test_and_set_bit(action, &info->actions)) { >> + unsigned long t; >> + >> + switch (action) { >> + case TIMER_RING_WATCHDOG: >> + t = XENHCD_RING_JIFFIES; >> + break; >> + default: >> + t = XENHCD_SCAN_JIFFIES; >> + break; >> + } >> + mod_timer(&info->watchdog, t + jiffies); >> + } >> +} >> + >> +static ssize_t xenhcd_show_statistics(struct device *dev, >> + struct device_attribute *attr, char *buf) >> +{ >> + struct usb_hcd *hcd; >> + struct xenhcd_info *info; >> + unsigned long flags; >> + unsigned size; >> + >> + hcd = dev_get_drvdata(dev); >> + info = xenhcd_hcd_to_info(hcd); >> + >> + spin_lock_irqsave(&info->lock, flags); >> + >> + size = scnprintf(buf, PAGE_SIZE, "bus %s, device %s\n%s\n" >> + "xenhcd, hcd state %d\n", >> + hcd->self.controller->bus->name, >> + dev_name(hcd->self.controller), hcd->product_desc, >> + hcd->state); >> + >> + spin_unlock_irqrestore(&info->lock, flags); >> + >> + return size; >> +} >> + >> +static DEVICE_ATTR(statistics, S_IRUGO, xenhcd_show_statistics, NULL); > > DEVICE_ATTR_RO() please. Okay. > As you are adding new sysfs files, we need Documentation/ABI/ entries. Okay. > Also note that I will reject this sysfs file for the obvious reasons > that it violates the one-value-per-file sysfs rule. Nice try to sneak > this one by, don't ever do that again. Lesson learned. Hmm, I'm beginning to question the value of that file. May be I should just throw it away. Thanks for the quick feedback. Juergen -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/