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![Jan Beulich](/assets/img/avatar_default.png)
Older compilers don't recognize that "v" can't be used uninitialized; other code using hvm_get_parameter() zeros the value too, so follow suit here. Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
839 lines
19 KiB
C
839 lines
19 KiB
C
/******************************************************************************
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* Talks to Xen Store to figure out what devices we have.
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*
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* Copyright (C) 2005 Rusty Russell, IBM Corporation
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* Copyright (C) 2005 Mike Wray, Hewlett-Packard
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* Copyright (C) 2005, 2006 XenSource Ltd
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation; or, when distributed
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* separately from the Linux kernel or incorporated into other
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* software packages, subject to the following license:
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this source file (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use, copy, modify,
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* merge, publish, distribute, sublicense, and/or sell copies of the Software,
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* and to permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#define DPRINTK(fmt, args...) \
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pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
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__func__, __LINE__, ##args)
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#include <linux/kernel.h>
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#include <linux/err.h>
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#include <linux/string.h>
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#include <linux/ctype.h>
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#include <linux/fcntl.h>
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#include <linux/mm.h>
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#include <linux/proc_fs.h>
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#include <linux/notifier.h>
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#include <linux/kthread.h>
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#include <linux/mutex.h>
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#include <linux/io.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <asm/page.h>
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#include <asm/pgtable.h>
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#include <asm/xen/hypervisor.h>
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#include <xen/xen.h>
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#include <xen/xenbus.h>
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#include <xen/events.h>
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#include <xen/xen-ops.h>
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#include <xen/page.h>
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#include <xen/hvm.h>
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#include "xenbus_comms.h"
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#include "xenbus_probe.h"
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int xen_store_evtchn;
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EXPORT_SYMBOL_GPL(xen_store_evtchn);
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struct xenstore_domain_interface *xen_store_interface;
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EXPORT_SYMBOL_GPL(xen_store_interface);
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enum xenstore_init xen_store_domain_type;
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EXPORT_SYMBOL_GPL(xen_store_domain_type);
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static unsigned long xen_store_mfn;
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static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
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/* If something in array of ids matches this device, return it. */
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static const struct xenbus_device_id *
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match_device(const struct xenbus_device_id *arr, struct xenbus_device *dev)
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{
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for (; *arr->devicetype != '\0'; arr++) {
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if (!strcmp(arr->devicetype, dev->devicetype))
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return arr;
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}
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return NULL;
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}
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int xenbus_match(struct device *_dev, struct device_driver *_drv)
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{
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struct xenbus_driver *drv = to_xenbus_driver(_drv);
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if (!drv->ids)
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return 0;
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return match_device(drv->ids, to_xenbus_device(_dev)) != NULL;
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}
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EXPORT_SYMBOL_GPL(xenbus_match);
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static void free_otherend_details(struct xenbus_device *dev)
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{
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kfree(dev->otherend);
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dev->otherend = NULL;
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}
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static void free_otherend_watch(struct xenbus_device *dev)
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{
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if (dev->otherend_watch.node) {
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unregister_xenbus_watch(&dev->otherend_watch);
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kfree(dev->otherend_watch.node);
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dev->otherend_watch.node = NULL;
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}
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}
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static int talk_to_otherend(struct xenbus_device *dev)
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{
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struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
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free_otherend_watch(dev);
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free_otherend_details(dev);
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return drv->read_otherend_details(dev);
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}
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static int watch_otherend(struct xenbus_device *dev)
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{
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struct xen_bus_type *bus =
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container_of(dev->dev.bus, struct xen_bus_type, bus);
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return xenbus_watch_pathfmt(dev, &dev->otherend_watch,
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bus->otherend_changed,
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"%s/%s", dev->otherend, "state");
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}
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int xenbus_read_otherend_details(struct xenbus_device *xendev,
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char *id_node, char *path_node)
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{
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int err = xenbus_gather(XBT_NIL, xendev->nodename,
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id_node, "%i", &xendev->otherend_id,
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path_node, NULL, &xendev->otherend,
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NULL);
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if (err) {
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xenbus_dev_fatal(xendev, err,
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"reading other end details from %s",
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xendev->nodename);
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return err;
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}
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if (strlen(xendev->otherend) == 0 ||
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!xenbus_exists(XBT_NIL, xendev->otherend, "")) {
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xenbus_dev_fatal(xendev, -ENOENT,
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"unable to read other end from %s. "
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"missing or inaccessible.",
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xendev->nodename);
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free_otherend_details(xendev);
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return -ENOENT;
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}
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return 0;
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}
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EXPORT_SYMBOL_GPL(xenbus_read_otherend_details);
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void xenbus_otherend_changed(struct xenbus_watch *watch,
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const char **vec, unsigned int len,
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int ignore_on_shutdown)
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{
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struct xenbus_device *dev =
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container_of(watch, struct xenbus_device, otherend_watch);
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struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
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enum xenbus_state state;
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/* Protect us against watches firing on old details when the otherend
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details change, say immediately after a resume. */
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if (!dev->otherend ||
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strncmp(dev->otherend, vec[XS_WATCH_PATH],
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strlen(dev->otherend))) {
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dev_dbg(&dev->dev, "Ignoring watch at %s\n",
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vec[XS_WATCH_PATH]);
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return;
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}
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state = xenbus_read_driver_state(dev->otherend);
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dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n",
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state, xenbus_strstate(state), dev->otherend_watch.node,
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vec[XS_WATCH_PATH]);
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/*
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* Ignore xenbus transitions during shutdown. This prevents us doing
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* work that can fail e.g., when the rootfs is gone.
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*/
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if (system_state > SYSTEM_RUNNING) {
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if (ignore_on_shutdown && (state == XenbusStateClosing))
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xenbus_frontend_closed(dev);
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return;
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}
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if (drv->otherend_changed)
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drv->otherend_changed(dev, state);
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}
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EXPORT_SYMBOL_GPL(xenbus_otherend_changed);
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int xenbus_dev_probe(struct device *_dev)
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{
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struct xenbus_device *dev = to_xenbus_device(_dev);
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struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
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const struct xenbus_device_id *id;
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int err;
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DPRINTK("%s", dev->nodename);
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if (!drv->probe) {
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err = -ENODEV;
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goto fail;
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}
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id = match_device(drv->ids, dev);
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if (!id) {
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err = -ENODEV;
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goto fail;
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}
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err = talk_to_otherend(dev);
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if (err) {
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dev_warn(&dev->dev, "talk_to_otherend on %s failed.\n",
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dev->nodename);
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return err;
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}
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err = drv->probe(dev, id);
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if (err)
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goto fail;
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err = watch_otherend(dev);
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if (err) {
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dev_warn(&dev->dev, "watch_otherend on %s failed.\n",
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dev->nodename);
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return err;
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}
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return 0;
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fail:
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xenbus_dev_error(dev, err, "xenbus_dev_probe on %s", dev->nodename);
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xenbus_switch_state(dev, XenbusStateClosed);
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return err;
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}
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EXPORT_SYMBOL_GPL(xenbus_dev_probe);
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int xenbus_dev_remove(struct device *_dev)
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{
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struct xenbus_device *dev = to_xenbus_device(_dev);
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struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
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DPRINTK("%s", dev->nodename);
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free_otherend_watch(dev);
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if (drv->remove)
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drv->remove(dev);
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free_otherend_details(dev);
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xenbus_switch_state(dev, XenbusStateClosed);
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return 0;
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}
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EXPORT_SYMBOL_GPL(xenbus_dev_remove);
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void xenbus_dev_shutdown(struct device *_dev)
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{
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struct xenbus_device *dev = to_xenbus_device(_dev);
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unsigned long timeout = 5*HZ;
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DPRINTK("%s", dev->nodename);
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get_device(&dev->dev);
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if (dev->state != XenbusStateConnected) {
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pr_info("%s: %s: %s != Connected, skipping\n",
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__func__, dev->nodename, xenbus_strstate(dev->state));
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goto out;
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}
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xenbus_switch_state(dev, XenbusStateClosing);
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timeout = wait_for_completion_timeout(&dev->down, timeout);
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if (!timeout)
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pr_info("%s: %s timeout closing device\n",
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__func__, dev->nodename);
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out:
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put_device(&dev->dev);
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}
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EXPORT_SYMBOL_GPL(xenbus_dev_shutdown);
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int xenbus_register_driver_common(struct xenbus_driver *drv,
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struct xen_bus_type *bus,
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struct module *owner, const char *mod_name)
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{
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drv->driver.name = drv->name ? drv->name : drv->ids[0].devicetype;
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drv->driver.bus = &bus->bus;
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drv->driver.owner = owner;
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drv->driver.mod_name = mod_name;
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return driver_register(&drv->driver);
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}
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EXPORT_SYMBOL_GPL(xenbus_register_driver_common);
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void xenbus_unregister_driver(struct xenbus_driver *drv)
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{
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driver_unregister(&drv->driver);
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}
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EXPORT_SYMBOL_GPL(xenbus_unregister_driver);
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struct xb_find_info {
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struct xenbus_device *dev;
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const char *nodename;
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};
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static int cmp_dev(struct device *dev, void *data)
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{
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struct xenbus_device *xendev = to_xenbus_device(dev);
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struct xb_find_info *info = data;
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if (!strcmp(xendev->nodename, info->nodename)) {
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info->dev = xendev;
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get_device(dev);
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return 1;
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}
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return 0;
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}
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static struct xenbus_device *xenbus_device_find(const char *nodename,
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struct bus_type *bus)
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{
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struct xb_find_info info = { .dev = NULL, .nodename = nodename };
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bus_for_each_dev(bus, NULL, &info, cmp_dev);
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return info.dev;
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}
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static int cleanup_dev(struct device *dev, void *data)
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{
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struct xenbus_device *xendev = to_xenbus_device(dev);
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struct xb_find_info *info = data;
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int len = strlen(info->nodename);
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DPRINTK("%s", info->nodename);
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|
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/* Match the info->nodename path, or any subdirectory of that path. */
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if (strncmp(xendev->nodename, info->nodename, len))
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return 0;
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|
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/* If the node name is longer, ensure it really is a subdirectory. */
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if ((strlen(xendev->nodename) > len) && (xendev->nodename[len] != '/'))
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return 0;
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info->dev = xendev;
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get_device(dev);
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return 1;
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}
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|
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static void xenbus_cleanup_devices(const char *path, struct bus_type *bus)
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{
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struct xb_find_info info = { .nodename = path };
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|
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do {
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info.dev = NULL;
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bus_for_each_dev(bus, NULL, &info, cleanup_dev);
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if (info.dev) {
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device_unregister(&info.dev->dev);
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put_device(&info.dev->dev);
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}
|
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} while (info.dev);
|
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}
|
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|
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static void xenbus_dev_release(struct device *dev)
|
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{
|
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if (dev)
|
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kfree(to_xenbus_device(dev));
|
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}
|
|
|
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static ssize_t nodename_show(struct device *dev,
|
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struct device_attribute *attr, char *buf)
|
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{
|
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return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename);
|
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}
|
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static DEVICE_ATTR_RO(nodename);
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|
|
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static ssize_t devtype_show(struct device *dev,
|
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struct device_attribute *attr, char *buf)
|
|
{
|
|
return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype);
|
|
}
|
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static DEVICE_ATTR_RO(devtype);
|
|
|
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static ssize_t modalias_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
return sprintf(buf, "%s:%s\n", dev->bus->name,
|
|
to_xenbus_device(dev)->devicetype);
|
|
}
|
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static DEVICE_ATTR_RO(modalias);
|
|
|
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static struct attribute *xenbus_dev_attrs[] = {
|
|
&dev_attr_nodename.attr,
|
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&dev_attr_devtype.attr,
|
|
&dev_attr_modalias.attr,
|
|
NULL,
|
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};
|
|
|
|
static const struct attribute_group xenbus_dev_group = {
|
|
.attrs = xenbus_dev_attrs,
|
|
};
|
|
|
|
const struct attribute_group *xenbus_dev_groups[] = {
|
|
&xenbus_dev_group,
|
|
NULL,
|
|
};
|
|
EXPORT_SYMBOL_GPL(xenbus_dev_groups);
|
|
|
|
int xenbus_probe_node(struct xen_bus_type *bus,
|
|
const char *type,
|
|
const char *nodename)
|
|
{
|
|
char devname[XEN_BUS_ID_SIZE];
|
|
int err;
|
|
struct xenbus_device *xendev;
|
|
size_t stringlen;
|
|
char *tmpstring;
|
|
|
|
enum xenbus_state state = xenbus_read_driver_state(nodename);
|
|
|
|
if (state != XenbusStateInitialising) {
|
|
/* Device is not new, so ignore it. This can happen if a
|
|
device is going away after switching to Closed. */
|
|
return 0;
|
|
}
|
|
|
|
stringlen = strlen(nodename) + 1 + strlen(type) + 1;
|
|
xendev = kzalloc(sizeof(*xendev) + stringlen, GFP_KERNEL);
|
|
if (!xendev)
|
|
return -ENOMEM;
|
|
|
|
xendev->state = XenbusStateInitialising;
|
|
|
|
/* Copy the strings into the extra space. */
|
|
|
|
tmpstring = (char *)(xendev + 1);
|
|
strcpy(tmpstring, nodename);
|
|
xendev->nodename = tmpstring;
|
|
|
|
tmpstring += strlen(tmpstring) + 1;
|
|
strcpy(tmpstring, type);
|
|
xendev->devicetype = tmpstring;
|
|
init_completion(&xendev->down);
|
|
|
|
xendev->dev.bus = &bus->bus;
|
|
xendev->dev.release = xenbus_dev_release;
|
|
|
|
err = bus->get_bus_id(devname, xendev->nodename);
|
|
if (err)
|
|
goto fail;
|
|
|
|
dev_set_name(&xendev->dev, "%s", devname);
|
|
|
|
/* Register with generic device framework. */
|
|
err = device_register(&xendev->dev);
|
|
if (err)
|
|
goto fail;
|
|
|
|
return 0;
|
|
fail:
|
|
kfree(xendev);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(xenbus_probe_node);
|
|
|
|
static int xenbus_probe_device_type(struct xen_bus_type *bus, const char *type)
|
|
{
|
|
int err = 0;
|
|
char **dir;
|
|
unsigned int dir_n = 0;
|
|
int i;
|
|
|
|
dir = xenbus_directory(XBT_NIL, bus->root, type, &dir_n);
|
|
if (IS_ERR(dir))
|
|
return PTR_ERR(dir);
|
|
|
|
for (i = 0; i < dir_n; i++) {
|
|
err = bus->probe(bus, type, dir[i]);
|
|
if (err)
|
|
break;
|
|
}
|
|
|
|
kfree(dir);
|
|
return err;
|
|
}
|
|
|
|
int xenbus_probe_devices(struct xen_bus_type *bus)
|
|
{
|
|
int err = 0;
|
|
char **dir;
|
|
unsigned int i, dir_n;
|
|
|
|
dir = xenbus_directory(XBT_NIL, bus->root, "", &dir_n);
|
|
if (IS_ERR(dir))
|
|
return PTR_ERR(dir);
|
|
|
|
for (i = 0; i < dir_n; i++) {
|
|
err = xenbus_probe_device_type(bus, dir[i]);
|
|
if (err)
|
|
break;
|
|
}
|
|
|
|
kfree(dir);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(xenbus_probe_devices);
|
|
|
|
static unsigned int char_count(const char *str, char c)
|
|
{
|
|
unsigned int i, ret = 0;
|
|
|
|
for (i = 0; str[i]; i++)
|
|
if (str[i] == c)
|
|
ret++;
|
|
return ret;
|
|
}
|
|
|
|
static int strsep_len(const char *str, char c, unsigned int len)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; str[i]; i++)
|
|
if (str[i] == c) {
|
|
if (len == 0)
|
|
return i;
|
|
len--;
|
|
}
|
|
return (len == 0) ? i : -ERANGE;
|
|
}
|
|
|
|
void xenbus_dev_changed(const char *node, struct xen_bus_type *bus)
|
|
{
|
|
int exists, rootlen;
|
|
struct xenbus_device *dev;
|
|
char type[XEN_BUS_ID_SIZE];
|
|
const char *p, *root;
|
|
|
|
if (char_count(node, '/') < 2)
|
|
return;
|
|
|
|
exists = xenbus_exists(XBT_NIL, node, "");
|
|
if (!exists) {
|
|
xenbus_cleanup_devices(node, &bus->bus);
|
|
return;
|
|
}
|
|
|
|
/* backend/<type>/... or device/<type>/... */
|
|
p = strchr(node, '/') + 1;
|
|
snprintf(type, XEN_BUS_ID_SIZE, "%.*s", (int)strcspn(p, "/"), p);
|
|
type[XEN_BUS_ID_SIZE-1] = '\0';
|
|
|
|
rootlen = strsep_len(node, '/', bus->levels);
|
|
if (rootlen < 0)
|
|
return;
|
|
root = kasprintf(GFP_KERNEL, "%.*s", rootlen, node);
|
|
if (!root)
|
|
return;
|
|
|
|
dev = xenbus_device_find(root, &bus->bus);
|
|
if (!dev)
|
|
xenbus_probe_node(bus, type, root);
|
|
else
|
|
put_device(&dev->dev);
|
|
|
|
kfree(root);
|
|
}
|
|
EXPORT_SYMBOL_GPL(xenbus_dev_changed);
|
|
|
|
int xenbus_dev_suspend(struct device *dev)
|
|
{
|
|
int err = 0;
|
|
struct xenbus_driver *drv;
|
|
struct xenbus_device *xdev
|
|
= container_of(dev, struct xenbus_device, dev);
|
|
|
|
DPRINTK("%s", xdev->nodename);
|
|
|
|
if (dev->driver == NULL)
|
|
return 0;
|
|
drv = to_xenbus_driver(dev->driver);
|
|
if (drv->suspend)
|
|
err = drv->suspend(xdev);
|
|
if (err)
|
|
pr_warn("suspend %s failed: %i\n", dev_name(dev), err);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(xenbus_dev_suspend);
|
|
|
|
int xenbus_dev_resume(struct device *dev)
|
|
{
|
|
int err;
|
|
struct xenbus_driver *drv;
|
|
struct xenbus_device *xdev
|
|
= container_of(dev, struct xenbus_device, dev);
|
|
|
|
DPRINTK("%s", xdev->nodename);
|
|
|
|
if (dev->driver == NULL)
|
|
return 0;
|
|
drv = to_xenbus_driver(dev->driver);
|
|
err = talk_to_otherend(xdev);
|
|
if (err) {
|
|
pr_warn("resume (talk_to_otherend) %s failed: %i\n",
|
|
dev_name(dev), err);
|
|
return err;
|
|
}
|
|
|
|
xdev->state = XenbusStateInitialising;
|
|
|
|
if (drv->resume) {
|
|
err = drv->resume(xdev);
|
|
if (err) {
|
|
pr_warn("resume %s failed: %i\n", dev_name(dev), err);
|
|
return err;
|
|
}
|
|
}
|
|
|
|
err = watch_otherend(xdev);
|
|
if (err) {
|
|
pr_warn("resume (watch_otherend) %s failed: %d.\n",
|
|
dev_name(dev), err);
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(xenbus_dev_resume);
|
|
|
|
int xenbus_dev_cancel(struct device *dev)
|
|
{
|
|
/* Do nothing */
|
|
DPRINTK("cancel");
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(xenbus_dev_cancel);
|
|
|
|
/* A flag to determine if xenstored is 'ready' (i.e. has started) */
|
|
int xenstored_ready;
|
|
|
|
|
|
int register_xenstore_notifier(struct notifier_block *nb)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (xenstored_ready > 0)
|
|
ret = nb->notifier_call(nb, 0, NULL);
|
|
else
|
|
blocking_notifier_chain_register(&xenstore_chain, nb);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(register_xenstore_notifier);
|
|
|
|
void unregister_xenstore_notifier(struct notifier_block *nb)
|
|
{
|
|
blocking_notifier_chain_unregister(&xenstore_chain, nb);
|
|
}
|
|
EXPORT_SYMBOL_GPL(unregister_xenstore_notifier);
|
|
|
|
void xenbus_probe(struct work_struct *unused)
|
|
{
|
|
xenstored_ready = 1;
|
|
|
|
/* Notify others that xenstore is up */
|
|
blocking_notifier_call_chain(&xenstore_chain, 0, NULL);
|
|
}
|
|
EXPORT_SYMBOL_GPL(xenbus_probe);
|
|
|
|
static int __init xenbus_probe_initcall(void)
|
|
{
|
|
if (!xen_domain())
|
|
return -ENODEV;
|
|
|
|
if (xen_initial_domain() || xen_hvm_domain())
|
|
return 0;
|
|
|
|
xenbus_probe(NULL);
|
|
return 0;
|
|
}
|
|
|
|
device_initcall(xenbus_probe_initcall);
|
|
|
|
/* Set up event channel for xenstored which is run as a local process
|
|
* (this is normally used only in dom0)
|
|
*/
|
|
static int __init xenstored_local_init(void)
|
|
{
|
|
int err = 0;
|
|
unsigned long page = 0;
|
|
struct evtchn_alloc_unbound alloc_unbound;
|
|
|
|
/* Allocate Xenstore page */
|
|
page = get_zeroed_page(GFP_KERNEL);
|
|
if (!page)
|
|
goto out_err;
|
|
|
|
xen_store_mfn = xen_start_info->store_mfn =
|
|
pfn_to_mfn(virt_to_phys((void *)page) >>
|
|
PAGE_SHIFT);
|
|
|
|
/* Next allocate a local port which xenstored can bind to */
|
|
alloc_unbound.dom = DOMID_SELF;
|
|
alloc_unbound.remote_dom = DOMID_SELF;
|
|
|
|
err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
|
|
&alloc_unbound);
|
|
if (err == -ENOSYS)
|
|
goto out_err;
|
|
|
|
BUG_ON(err);
|
|
xen_store_evtchn = xen_start_info->store_evtchn =
|
|
alloc_unbound.port;
|
|
|
|
return 0;
|
|
|
|
out_err:
|
|
if (page != 0)
|
|
free_page(page);
|
|
return err;
|
|
}
|
|
|
|
static int xenbus_resume_cb(struct notifier_block *nb,
|
|
unsigned long action, void *data)
|
|
{
|
|
int err = 0;
|
|
|
|
if (xen_hvm_domain()) {
|
|
uint64_t v = 0;
|
|
|
|
err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
|
|
if (!err && v)
|
|
xen_store_evtchn = v;
|
|
else
|
|
pr_warn("Cannot update xenstore event channel: %d\n",
|
|
err);
|
|
} else
|
|
xen_store_evtchn = xen_start_info->store_evtchn;
|
|
|
|
return err;
|
|
}
|
|
|
|
static struct notifier_block xenbus_resume_nb = {
|
|
.notifier_call = xenbus_resume_cb,
|
|
};
|
|
|
|
static int __init xenbus_init(void)
|
|
{
|
|
int err = 0;
|
|
uint64_t v = 0;
|
|
xen_store_domain_type = XS_UNKNOWN;
|
|
|
|
if (!xen_domain())
|
|
return -ENODEV;
|
|
|
|
xenbus_ring_ops_init();
|
|
|
|
if (xen_pv_domain())
|
|
xen_store_domain_type = XS_PV;
|
|
if (xen_hvm_domain())
|
|
xen_store_domain_type = XS_HVM;
|
|
if (xen_hvm_domain() && xen_initial_domain())
|
|
xen_store_domain_type = XS_LOCAL;
|
|
if (xen_pv_domain() && !xen_start_info->store_evtchn)
|
|
xen_store_domain_type = XS_LOCAL;
|
|
if (xen_pv_domain() && xen_start_info->store_evtchn)
|
|
xenstored_ready = 1;
|
|
|
|
switch (xen_store_domain_type) {
|
|
case XS_LOCAL:
|
|
err = xenstored_local_init();
|
|
if (err)
|
|
goto out_error;
|
|
xen_store_interface = mfn_to_virt(xen_store_mfn);
|
|
break;
|
|
case XS_PV:
|
|
xen_store_evtchn = xen_start_info->store_evtchn;
|
|
xen_store_mfn = xen_start_info->store_mfn;
|
|
xen_store_interface = mfn_to_virt(xen_store_mfn);
|
|
break;
|
|
case XS_HVM:
|
|
err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
|
|
if (err)
|
|
goto out_error;
|
|
xen_store_evtchn = (int)v;
|
|
err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
|
|
if (err)
|
|
goto out_error;
|
|
xen_store_mfn = (unsigned long)v;
|
|
xen_store_interface =
|
|
xen_remap(xen_store_mfn << PAGE_SHIFT, PAGE_SIZE);
|
|
break;
|
|
default:
|
|
pr_warn("Xenstore state unknown\n");
|
|
break;
|
|
}
|
|
|
|
/* Initialize the interface to xenstore. */
|
|
err = xs_init();
|
|
if (err) {
|
|
pr_warn("Error initializing xenstore comms: %i\n", err);
|
|
goto out_error;
|
|
}
|
|
|
|
if ((xen_store_domain_type != XS_LOCAL) &&
|
|
(xen_store_domain_type != XS_UNKNOWN))
|
|
xen_resume_notifier_register(&xenbus_resume_nb);
|
|
|
|
#ifdef CONFIG_XEN_COMPAT_XENFS
|
|
/*
|
|
* Create xenfs mountpoint in /proc for compatibility with
|
|
* utilities that expect to find "xenbus" under "/proc/xen".
|
|
*/
|
|
proc_mkdir("xen", NULL);
|
|
#endif
|
|
|
|
out_error:
|
|
return err;
|
|
}
|
|
|
|
postcore_initcall(xenbus_init);
|
|
|
|
MODULE_LICENSE("GPL");
|