tristate "Xen virtual block device support"
depends on XEN
default y
+ select XEN_XENBUS_FRONTEND
help
This driver implements the front-end of the Xen virtual
block device driver. It communicates with a back-end driver
config XEN_NETDEV_FRONTEND
tristate "Xen network device frontend driver"
depends on XEN
+ select XEN_XENBUS_FRONTEND
default y
help
The network device frontend driver allows the kernel to
depends on PCI && X86 && XEN
select HOTPLUG
select PCI_XEN
+ select XEN_XENBUS_FRONTEND
default y
help
The PCI device frontend driver allows the kernel to import arbitrary
firing.
If in doubt, say yes.
+config XEN_BACKEND
+ bool "Backend driver support"
+ depends on XEN_DOM0
+ default y
+ help
+ Support for backend device drivers that provide I/O services
+ to other virtual machines.
+
config XENFS
tristate "Xen filesystem"
default y
virtual environment, /sys/hypervisor will still be present,
but will have no xen contents.
+config XEN_XENBUS_FRONTEND
+ tristate
+
config XEN_PLATFORM_PCI
tristate "xen platform pci device driver"
depends on XEN_PVHVM
xenbus-objs += xenbus_comms.o
xenbus-objs += xenbus_xs.o
xenbus-objs += xenbus_probe.o
+
+xenbus-be-objs-$(CONFIG_XEN_BACKEND) += xenbus_probe_backend.o
+xenbus-objs += $(xenbus-be-objs-y)
+
+obj-$(CONFIG_XEN_XENBUS_FRONTEND) += xenbus_probe_frontend.o
#include <xen/events.h>
#include <xen/page.h>
-#include <xen/platform_pci.h>
#include <xen/hvm.h>
#include "xenbus_comms.h"
static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
-static void wait_for_devices(struct xenbus_driver *xendrv);
-
-static int xenbus_probe_frontend(const char *type, const char *name);
-
-static void xenbus_dev_shutdown(struct device *_dev);
-
-static int xenbus_dev_suspend(struct device *dev, pm_message_t state);
-static int xenbus_dev_resume(struct device *dev);
-
/* If something in array of ids matches this device, return it. */
static const struct xenbus_device_id *
match_device(const struct xenbus_device_id *arr, struct xenbus_device *dev)
return match_device(drv->ids, to_xenbus_device(_dev)) != NULL;
}
-
-static int xenbus_uevent(struct device *_dev, struct kobj_uevent_env *env)
-{
- struct xenbus_device *dev = to_xenbus_device(_dev);
-
- if (add_uevent_var(env, "MODALIAS=xen:%s", dev->devicetype))
- return -ENOMEM;
-
- return 0;
-}
-
-/* device/<type>/<id> => <type>-<id> */
-static int frontend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename)
-{
- nodename = strchr(nodename, '/');
- if (!nodename || strlen(nodename + 1) >= XEN_BUS_ID_SIZE) {
- printk(KERN_WARNING "XENBUS: bad frontend %s\n", nodename);
- return -EINVAL;
- }
-
- strlcpy(bus_id, nodename + 1, XEN_BUS_ID_SIZE);
- if (!strchr(bus_id, '/')) {
- printk(KERN_WARNING "XENBUS: bus_id %s no slash\n", bus_id);
- return -EINVAL;
- }
- *strchr(bus_id, '/') = '-';
- return 0;
-}
+EXPORT_SYMBOL_GPL(xenbus_match);
static void free_otherend_details(struct xenbus_device *dev)
}
-int read_otherend_details(struct xenbus_device *xendev,
+static int talk_to_otherend(struct xenbus_device *dev)
+{
+ struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
+
+ free_otherend_watch(dev);
+ free_otherend_details(dev);
+
+ return drv->read_otherend_details(dev);
+}
+
+
+
+static int watch_otherend(struct xenbus_device *dev)
+{
+ struct xen_bus_type *bus =
+ container_of(dev->dev.bus, struct xen_bus_type, bus);
+
+ return xenbus_watch_pathfmt(dev, &dev->otherend_watch,
+ bus->otherend_changed,
+ "%s/%s", dev->otherend, "state");
+}
+
+
+int xenbus_read_otherend_details(struct xenbus_device *xendev,
char *id_node, char *path_node)
{
int err = xenbus_gather(XBT_NIL, xendev->nodename,
return 0;
}
+EXPORT_SYMBOL_GPL(xenbus_read_otherend_details);
-
-static int read_backend_details(struct xenbus_device *xendev)
-{
- return read_otherend_details(xendev, "backend-id", "backend");
-}
-
-static struct device_attribute xenbus_dev_attrs[] = {
- __ATTR_NULL
-};
-
-/* Bus type for frontend drivers. */
-static struct xen_bus_type xenbus_frontend = {
- .root = "device",
- .levels = 2, /* device/type/<id> */
- .get_bus_id = frontend_bus_id,
- .probe = xenbus_probe_frontend,
- .bus = {
- .name = "xen",
- .match = xenbus_match,
- .uevent = xenbus_uevent,
- .probe = xenbus_dev_probe,
- .remove = xenbus_dev_remove,
- .shutdown = xenbus_dev_shutdown,
- .dev_attrs = xenbus_dev_attrs,
-
- .suspend = xenbus_dev_suspend,
- .resume = xenbus_dev_resume,
- },
-};
-
-static void otherend_changed(struct xenbus_watch *watch,
- const char **vec, unsigned int len)
+void xenbus_otherend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len,
+ int ignore_on_shutdown)
{
struct xenbus_device *dev =
container_of(watch, struct xenbus_device, otherend_watch);
* work that can fail e.g., when the rootfs is gone.
*/
if (system_state > SYSTEM_RUNNING) {
- struct xen_bus_type *bus = bus;
- bus = container_of(dev->dev.bus, struct xen_bus_type, bus);
- /* If we're frontend, drive the state machine to Closed. */
- /* This should cause the backend to release our resources. */
- if ((bus == &xenbus_frontend) && (state == XenbusStateClosing))
+ if (ignore_on_shutdown && (state == XenbusStateClosing))
xenbus_frontend_closed(dev);
return;
}
if (drv->otherend_changed)
drv->otherend_changed(dev, state);
}
-
-
-static int talk_to_otherend(struct xenbus_device *dev)
-{
- struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
-
- free_otherend_watch(dev);
- free_otherend_details(dev);
-
- return drv->read_otherend_details(dev);
-}
-
-
-static int watch_otherend(struct xenbus_device *dev)
-{
- return xenbus_watch_pathfmt(dev, &dev->otherend_watch, otherend_changed,
- "%s/%s", dev->otherend, "state");
-}
-
+EXPORT_SYMBOL_GPL(xenbus_otherend_changed);
int xenbus_dev_probe(struct device *_dev)
{
fail:
xenbus_dev_error(dev, err, "xenbus_dev_probe on %s", dev->nodename);
xenbus_switch_state(dev, XenbusStateClosed);
- return -ENODEV;
+ return err;
}
+EXPORT_SYMBOL_GPL(xenbus_dev_probe);
int xenbus_dev_remove(struct device *_dev)
{
xenbus_switch_state(dev, XenbusStateClosed);
return 0;
}
+EXPORT_SYMBOL_GPL(xenbus_dev_remove);
-static void xenbus_dev_shutdown(struct device *_dev)
+void xenbus_dev_shutdown(struct device *_dev)
{
struct xenbus_device *dev = to_xenbus_device(_dev);
unsigned long timeout = 5*HZ;
out:
put_device(&dev->dev);
}
+EXPORT_SYMBOL_GPL(xenbus_dev_shutdown);
int xenbus_register_driver_common(struct xenbus_driver *drv,
struct xen_bus_type *bus,
return driver_register(&drv->driver);
}
-
-int __xenbus_register_frontend(struct xenbus_driver *drv,
- struct module *owner, const char *mod_name)
-{
- int ret;
-
- drv->read_otherend_details = read_backend_details;
-
- ret = xenbus_register_driver_common(drv, &xenbus_frontend,
- owner, mod_name);
- if (ret)
- return ret;
-
- /* If this driver is loaded as a module wait for devices to attach. */
- wait_for_devices(drv);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(__xenbus_register_frontend);
+EXPORT_SYMBOL_GPL(xenbus_register_driver_common);
void xenbus_unregister_driver(struct xenbus_driver *drv)
{
kfree(xendev);
return err;
}
-
-/* device/<typename>/<name> */
-static int xenbus_probe_frontend(const char *type, const char *name)
-{
- char *nodename;
- int err;
-
- nodename = kasprintf(GFP_KERNEL, "%s/%s/%s",
- xenbus_frontend.root, type, name);
- if (!nodename)
- return -ENOMEM;
-
- DPRINTK("%s", nodename);
-
- err = xenbus_probe_node(&xenbus_frontend, type, nodename);
- kfree(nodename);
- return err;
-}
+EXPORT_SYMBOL_GPL(xenbus_probe_node);
static int xenbus_probe_device_type(struct xen_bus_type *bus, const char *type)
{
return PTR_ERR(dir);
for (i = 0; i < dir_n; i++) {
- err = bus->probe(type, dir[i]);
+ err = bus->probe(bus, type, dir[i]);
if (err)
break;
}
+
kfree(dir);
return err;
}
if (err)
break;
}
+
kfree(dir);
return err;
}
+EXPORT_SYMBOL_GPL(xenbus_probe_devices);
static unsigned int char_count(const char *str, char c)
{
}
EXPORT_SYMBOL_GPL(xenbus_dev_changed);
-static void frontend_changed(struct xenbus_watch *watch,
- const char **vec, unsigned int len)
-{
- DPRINTK("");
-
- xenbus_dev_changed(vec[XS_WATCH_PATH], &xenbus_frontend);
-}
-
-/* We watch for devices appearing and vanishing. */
-static struct xenbus_watch fe_watch = {
- .node = "device",
- .callback = frontend_changed,
-};
-
-static int xenbus_dev_suspend(struct device *dev, pm_message_t state)
+int xenbus_dev_suspend(struct device *dev, pm_message_t state)
{
int err = 0;
struct xenbus_driver *drv;
- struct xenbus_device *xdev;
+ struct xenbus_device *xdev
+ = container_of(dev, struct xenbus_device, dev);
- DPRINTK("");
+ DPRINTK("%s", xdev->nodename);
if (dev->driver == NULL)
return 0;
drv = to_xenbus_driver(dev->driver);
- xdev = container_of(dev, struct xenbus_device, dev);
if (drv->suspend)
err = drv->suspend(xdev, state);
if (err)
"xenbus: suspend %s failed: %i\n", dev_name(dev), err);
return 0;
}
+EXPORT_SYMBOL_GPL(xenbus_dev_suspend);
-static int xenbus_dev_resume(struct device *dev)
+int xenbus_dev_resume(struct device *dev)
{
int err;
struct xenbus_driver *drv;
- struct xenbus_device *xdev;
+ struct xenbus_device *xdev
+ = container_of(dev, struct xenbus_device, dev);
- DPRINTK("");
+ DPRINTK("%s", xdev->nodename);
if (dev->driver == NULL)
return 0;
-
drv = to_xenbus_driver(dev->driver);
- xdev = container_of(dev, struct xenbus_device, dev);
-
err = talk_to_otherend(xdev);
if (err) {
printk(KERN_WARNING
return 0;
}
+EXPORT_SYMBOL_GPL(xenbus_dev_resume);
/* A flag to determine if xenstored is 'ready' (i.e. has started) */
int xenstored_ready = 0;
{
xenstored_ready = 1;
- /* Enumerate devices in xenstore and watch for changes. */
- xenbus_probe_devices(&xenbus_frontend);
- register_xenbus_watch(&fe_watch);
- xenbus_backend_probe_and_watch();
-
/* Notify others that xenstore is up */
blocking_notifier_call_chain(&xenstore_chain, 0, NULL);
}
err = -ENODEV;
if (!xen_domain())
- goto out_error;
-
- /* Register ourselves with the kernel bus subsystem */
- err = bus_register(&xenbus_frontend.bus);
- if (err)
- goto out_error;
-
- err = xenbus_backend_bus_register();
- if (err)
- goto out_unreg_front;
+ return err;
/*
* Domain0 doesn't have a store_evtchn or store_mfn yet.
if (err) {
printk(KERN_WARNING
"XENBUS: Error initializing xenstore comms: %i\n", err);
- goto out_unreg_back;
+ goto out_error;
}
#ifdef CONFIG_XEN_COMPAT_XENFS
return 0;
- out_unreg_back:
- xenbus_backend_bus_unregister();
-
- out_unreg_front:
- bus_unregister(&xenbus_frontend.bus);
-
out_error:
if (page != 0)
free_page(page);
+
return err;
}
postcore_initcall(xenbus_init);
MODULE_LICENSE("GPL");
-
-static int is_device_connecting(struct device *dev, void *data)
-{
- struct xenbus_device *xendev = to_xenbus_device(dev);
- struct device_driver *drv = data;
- struct xenbus_driver *xendrv;
-
- /*
- * A device with no driver will never connect. We care only about
- * devices which should currently be in the process of connecting.
- */
- if (!dev->driver)
- return 0;
-
- /* Is this search limited to a particular driver? */
- if (drv && (dev->driver != drv))
- return 0;
-
- xendrv = to_xenbus_driver(dev->driver);
- return (xendev->state < XenbusStateConnected ||
- (xendev->state == XenbusStateConnected &&
- xendrv->is_ready && !xendrv->is_ready(xendev)));
-}
-
-static int exists_connecting_device(struct device_driver *drv)
-{
- return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
- is_device_connecting);
-}
-
-static int print_device_status(struct device *dev, void *data)
-{
- struct xenbus_device *xendev = to_xenbus_device(dev);
- struct device_driver *drv = data;
-
- /* Is this operation limited to a particular driver? */
- if (drv && (dev->driver != drv))
- return 0;
-
- if (!dev->driver) {
- /* Information only: is this too noisy? */
- printk(KERN_INFO "XENBUS: Device with no driver: %s\n",
- xendev->nodename);
- } else if (xendev->state < XenbusStateConnected) {
- enum xenbus_state rstate = XenbusStateUnknown;
- if (xendev->otherend)
- rstate = xenbus_read_driver_state(xendev->otherend);
- printk(KERN_WARNING "XENBUS: Timeout connecting "
- "to device: %s (local state %d, remote state %d)\n",
- xendev->nodename, xendev->state, rstate);
- }
-
- return 0;
-}
-
-/* We only wait for device setup after most initcalls have run. */
-static int ready_to_wait_for_devices;
-
-/*
- * On a 5-minute timeout, wait for all devices currently configured. We need
- * to do this to guarantee that the filesystems and / or network devices
- * needed for boot are available, before we can allow the boot to proceed.
- *
- * This needs to be on a late_initcall, to happen after the frontend device
- * drivers have been initialised, but before the root fs is mounted.
- *
- * A possible improvement here would be to have the tools add a per-device
- * flag to the store entry, indicating whether it is needed at boot time.
- * This would allow people who knew what they were doing to accelerate their
- * boot slightly, but of course needs tools or manual intervention to set up
- * those flags correctly.
- */
-static void wait_for_devices(struct xenbus_driver *xendrv)
-{
- unsigned long start = jiffies;
- struct device_driver *drv = xendrv ? &xendrv->driver : NULL;
- unsigned int seconds_waited = 0;
-
- if (!ready_to_wait_for_devices || !xen_domain())
- return;
-
- while (exists_connecting_device(drv)) {
- if (time_after(jiffies, start + (seconds_waited+5)*HZ)) {
- if (!seconds_waited)
- printk(KERN_WARNING "XENBUS: Waiting for "
- "devices to initialise: ");
- seconds_waited += 5;
- printk("%us...", 300 - seconds_waited);
- if (seconds_waited == 300)
- break;
- }
-
- schedule_timeout_interruptible(HZ/10);
- }
-
- if (seconds_waited)
- printk("\n");
-
- bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
- print_device_status);
-}
-
-#ifndef MODULE
-static int __init boot_wait_for_devices(void)
-{
- if (xen_hvm_domain() && !xen_platform_pci_unplug)
- return -ENODEV;
-
- ready_to_wait_for_devices = 1;
- wait_for_devices(NULL);
- return 0;
-}
-
-late_initcall(boot_wait_for_devices);
-#endif
#define XEN_BUS_ID_SIZE 20
-#ifdef CONFIG_XEN_BACKEND
-extern void xenbus_backend_suspend(int (*fn)(struct device *, void *));
-extern void xenbus_backend_resume(int (*fn)(struct device *, void *));
-extern void xenbus_backend_probe_and_watch(void);
-extern int xenbus_backend_bus_register(void);
-extern void xenbus_backend_bus_unregister(void);
-#else
-static inline void xenbus_backend_suspend(int (*fn)(struct device *, void *)) {}
-static inline void xenbus_backend_resume(int (*fn)(struct device *, void *)) {}
-static inline void xenbus_backend_probe_and_watch(void) {}
-static inline int xenbus_backend_bus_register(void) { return 0; }
-static inline void xenbus_backend_bus_unregister(void) {}
-#endif
-
struct xen_bus_type
{
char *root;
unsigned int levels;
int (*get_bus_id)(char bus_id[XEN_BUS_ID_SIZE], const char *nodename);
- int (*probe)(const char *type, const char *dir);
+ int (*probe)(struct xen_bus_type *bus, const char *type,
+ const char *dir);
+ void (*otherend_changed)(struct xenbus_watch *watch, const char **vec,
+ unsigned int len);
struct bus_type bus;
};
extern void xenbus_dev_changed(const char *node, struct xen_bus_type *bus);
+extern void xenbus_dev_shutdown(struct device *_dev);
+
+extern int xenbus_dev_suspend(struct device *dev, pm_message_t state);
+extern int xenbus_dev_resume(struct device *dev);
+
+extern void xenbus_otherend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len,
+ int ignore_on_shutdown);
+
+extern int xenbus_read_otherend_details(struct xenbus_device *xendev,
+ char *id_node, char *path_node);
+
#endif
--- /dev/null
+/******************************************************************************
+ * Talks to Xen Store to figure out what devices we have (backend half).
+ *
+ * Copyright (C) 2005 Rusty Russell, IBM Corporation
+ * Copyright (C) 2005 Mike Wray, Hewlett-Packard
+ * Copyright (C) 2005, 2006 XenSource Ltd
+ * Copyright (C) 2007 Solarflare Communications, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, 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 source file (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.
+ */
+
+#define DPRINTK(fmt, args...) \
+ pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
+ __func__, __LINE__, ##args)
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/notifier.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/hypervisor.h>
+#include <xen/xenbus.h>
+#include <xen/features.h>
+
+#include "xenbus_comms.h"
+#include "xenbus_probe.h"
+
+/* backend/<type>/<fe-uuid>/<id> => <type>-<fe-domid>-<id> */
+static int backend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename)
+{
+ int domid, err;
+ const char *devid, *type, *frontend;
+ unsigned int typelen;
+
+ type = strchr(nodename, '/');
+ if (!type)
+ return -EINVAL;
+ type++;
+ typelen = strcspn(type, "/");
+ if (!typelen || type[typelen] != '/')
+ return -EINVAL;
+
+ devid = strrchr(nodename, '/') + 1;
+
+ err = xenbus_gather(XBT_NIL, nodename, "frontend-id", "%i", &domid,
+ "frontend", NULL, &frontend,
+ NULL);
+ if (err)
+ return err;
+ if (strlen(frontend) == 0)
+ err = -ERANGE;
+ if (!err && !xenbus_exists(XBT_NIL, frontend, ""))
+ err = -ENOENT;
+ kfree(frontend);
+
+ if (err)
+ return err;
+
+ if (snprintf(bus_id, XEN_BUS_ID_SIZE, "%.*s-%i-%s",
+ typelen, type, domid, devid) >= XEN_BUS_ID_SIZE)
+ return -ENOSPC;
+ return 0;
+}
+
+static int xenbus_uevent_backend(struct device *dev,
+ struct kobj_uevent_env *env)
+{
+ struct xenbus_device *xdev;
+ struct xenbus_driver *drv;
+ struct xen_bus_type *bus;
+
+ DPRINTK("");
+
+ if (dev == NULL)
+ return -ENODEV;
+
+ xdev = to_xenbus_device(dev);
+ bus = container_of(xdev->dev.bus, struct xen_bus_type, bus);
+ if (xdev == NULL)
+ return -ENODEV;
+
+ /* stuff we want to pass to /sbin/hotplug */
+ if (add_uevent_var(env, "XENBUS_TYPE=%s", xdev->devicetype))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "XENBUS_PATH=%s", xdev->nodename))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "XENBUS_BASE_PATH=%s", bus->root))
+ return -ENOMEM;
+
+ if (dev->driver) {
+ drv = to_xenbus_driver(dev->driver);
+ if (drv && drv->uevent)
+ return drv->uevent(xdev, env);
+ }
+
+ return 0;
+}
+
+/* backend/<typename>/<frontend-uuid>/<name> */
+static int xenbus_probe_backend_unit(struct xen_bus_type *bus,
+ const char *dir,
+ const char *type,
+ const char *name)
+{
+ char *nodename;
+ int err;
+
+ nodename = kasprintf(GFP_KERNEL, "%s/%s", dir, name);
+ if (!nodename)
+ return -ENOMEM;
+
+ DPRINTK("%s\n", nodename);
+
+ err = xenbus_probe_node(bus, type, nodename);
+ kfree(nodename);
+ return err;
+}
+
+/* backend/<typename>/<frontend-domid> */
+static int xenbus_probe_backend(struct xen_bus_type *bus, const char *type,
+ const char *domid)
+{
+ char *nodename;
+ int err = 0;
+ char **dir;
+ unsigned int i, dir_n = 0;
+
+ DPRINTK("");
+
+ nodename = kasprintf(GFP_KERNEL, "%s/%s/%s", bus->root, type, domid);
+ if (!nodename)
+ return -ENOMEM;
+
+ dir = xenbus_directory(XBT_NIL, nodename, "", &dir_n);
+ if (IS_ERR(dir)) {
+ kfree(nodename);
+ return PTR_ERR(dir);
+ }
+
+ for (i = 0; i < dir_n; i++) {
+ err = xenbus_probe_backend_unit(bus, nodename, type, dir[i]);
+ if (err)
+ break;
+ }
+ kfree(dir);
+ kfree(nodename);
+ return err;
+}
+
+static void frontend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ xenbus_otherend_changed(watch, vec, len, 0);
+}
+
+static struct device_attribute xenbus_backend_dev_attrs[] = {
+ __ATTR_NULL
+};
+
+static struct xen_bus_type xenbus_backend = {
+ .root = "backend",
+ .levels = 3, /* backend/type/<frontend>/<id> */
+ .get_bus_id = backend_bus_id,
+ .probe = xenbus_probe_backend,
+ .otherend_changed = frontend_changed,
+ .bus = {
+ .name = "xen-backend",
+ .match = xenbus_match,
+ .uevent = xenbus_uevent_backend,
+ .probe = xenbus_dev_probe,
+ .remove = xenbus_dev_remove,
+ .shutdown = xenbus_dev_shutdown,
+ .dev_attrs = xenbus_backend_dev_attrs,
+ },
+};
+
+static void backend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ DPRINTK("");
+
+ xenbus_dev_changed(vec[XS_WATCH_PATH], &xenbus_backend);
+}
+
+static struct xenbus_watch be_watch = {
+ .node = "backend",
+ .callback = backend_changed,
+};
+
+static int read_frontend_details(struct xenbus_device *xendev)
+{
+ return xenbus_read_otherend_details(xendev, "frontend-id", "frontend");
+}
+
+int xenbus_dev_is_online(struct xenbus_device *dev)
+{
+ int rc, val;
+
+ rc = xenbus_scanf(XBT_NIL, dev->nodename, "online", "%d", &val);
+ if (rc != 1)
+ val = 0; /* no online node present */
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_is_online);
+
+int __xenbus_register_backend(struct xenbus_driver *drv,
+ struct module *owner, const char *mod_name)
+{
+ drv->read_otherend_details = read_frontend_details;
+
+ return xenbus_register_driver_common(drv, &xenbus_backend,
+ owner, mod_name);
+}
+EXPORT_SYMBOL_GPL(__xenbus_register_backend);
+
+static int backend_probe_and_watch(struct notifier_block *notifier,
+ unsigned long event,
+ void *data)
+{
+ /* Enumerate devices in xenstore and watch for changes. */
+ xenbus_probe_devices(&xenbus_backend);
+ register_xenbus_watch(&be_watch);
+
+ return NOTIFY_DONE;
+}
+
+static int __init xenbus_probe_backend_init(void)
+{
+ static struct notifier_block xenstore_notifier = {
+ .notifier_call = backend_probe_and_watch
+ };
+ int err;
+
+ DPRINTK("");
+
+ /* Register ourselves with the kernel bus subsystem */
+ err = bus_register(&xenbus_backend.bus);
+ if (err)
+ return err;
+
+ register_xenstore_notifier(&xenstore_notifier);
+
+ return 0;
+}
+subsys_initcall(xenbus_probe_backend_init);
--- /dev/null
+#define DPRINTK(fmt, args...) \
+ pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
+ __func__, __LINE__, ##args)
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/notifier.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/xen/hypervisor.h>
+#include <xen/xenbus.h>
+#include <xen/events.h>
+#include <xen/page.h>
+
+#include <xen/platform_pci.h>
+
+#include "xenbus_comms.h"
+#include "xenbus_probe.h"
+
+
+/* device/<type>/<id> => <type>-<id> */
+static int frontend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename)
+{
+ nodename = strchr(nodename, '/');
+ if (!nodename || strlen(nodename + 1) >= XEN_BUS_ID_SIZE) {
+ printk(KERN_WARNING "XENBUS: bad frontend %s\n", nodename);
+ return -EINVAL;
+ }
+
+ strlcpy(bus_id, nodename + 1, XEN_BUS_ID_SIZE);
+ if (!strchr(bus_id, '/')) {
+ printk(KERN_WARNING "XENBUS: bus_id %s no slash\n", bus_id);
+ return -EINVAL;
+ }
+ *strchr(bus_id, '/') = '-';
+ return 0;
+}
+
+/* device/<typename>/<name> */
+static int xenbus_probe_frontend(struct xen_bus_type *bus, const char *type,
+ const char *name)
+{
+ char *nodename;
+ int err;
+
+ nodename = kasprintf(GFP_KERNEL, "%s/%s/%s", bus->root, type, name);
+ if (!nodename)
+ return -ENOMEM;
+
+ DPRINTK("%s", nodename);
+
+ err = xenbus_probe_node(bus, type, nodename);
+ kfree(nodename);
+ return err;
+}
+
+static int xenbus_uevent_frontend(struct device *_dev,
+ struct kobj_uevent_env *env)
+{
+ struct xenbus_device *dev = to_xenbus_device(_dev);
+
+ if (add_uevent_var(env, "MODALIAS=xen:%s", dev->devicetype))
+ return -ENOMEM;
+
+ return 0;
+}
+
+
+static void backend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ xenbus_otherend_changed(watch, vec, len, 1);
+}
+
+static struct device_attribute xenbus_frontend_dev_attrs[] = {
+ __ATTR_NULL
+};
+
+static struct xen_bus_type xenbus_frontend = {
+ .root = "device",
+ .levels = 2, /* device/type/<id> */
+ .get_bus_id = frontend_bus_id,
+ .probe = xenbus_probe_frontend,
+ .otherend_changed = backend_changed,
+ .bus = {
+ .name = "xen",
+ .match = xenbus_match,
+ .uevent = xenbus_uevent_frontend,
+ .probe = xenbus_dev_probe,
+ .remove = xenbus_dev_remove,
+ .shutdown = xenbus_dev_shutdown,
+ .dev_attrs = xenbus_frontend_dev_attrs,
+
+ .suspend = xenbus_dev_suspend,
+ .resume = xenbus_dev_resume,
+ },
+};
+
+static void frontend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ DPRINTK("");
+
+ xenbus_dev_changed(vec[XS_WATCH_PATH], &xenbus_frontend);
+}
+
+
+/* We watch for devices appearing and vanishing. */
+static struct xenbus_watch fe_watch = {
+ .node = "device",
+ .callback = frontend_changed,
+};
+
+static int read_backend_details(struct xenbus_device *xendev)
+{
+ return xenbus_read_otherend_details(xendev, "backend-id", "backend");
+}
+
+static int is_device_connecting(struct device *dev, void *data)
+{
+ struct xenbus_device *xendev = to_xenbus_device(dev);
+ struct device_driver *drv = data;
+ struct xenbus_driver *xendrv;
+
+ /*
+ * A device with no driver will never connect. We care only about
+ * devices which should currently be in the process of connecting.
+ */
+ if (!dev->driver)
+ return 0;
+
+ /* Is this search limited to a particular driver? */
+ if (drv && (dev->driver != drv))
+ return 0;
+
+ xendrv = to_xenbus_driver(dev->driver);
+ return (xendev->state < XenbusStateConnected ||
+ (xendev->state == XenbusStateConnected &&
+ xendrv->is_ready && !xendrv->is_ready(xendev)));
+}
+
+static int exists_connecting_device(struct device_driver *drv)
+{
+ return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
+ is_device_connecting);
+}
+
+static int print_device_status(struct device *dev, void *data)
+{
+ struct xenbus_device *xendev = to_xenbus_device(dev);
+ struct device_driver *drv = data;
+
+ /* Is this operation limited to a particular driver? */
+ if (drv && (dev->driver != drv))
+ return 0;
+
+ if (!dev->driver) {
+ /* Information only: is this too noisy? */
+ printk(KERN_INFO "XENBUS: Device with no driver: %s\n",
+ xendev->nodename);
+ } else if (xendev->state < XenbusStateConnected) {
+ enum xenbus_state rstate = XenbusStateUnknown;
+ if (xendev->otherend)
+ rstate = xenbus_read_driver_state(xendev->otherend);
+ printk(KERN_WARNING "XENBUS: Timeout connecting "
+ "to device: %s (local state %d, remote state %d)\n",
+ xendev->nodename, xendev->state, rstate);
+ }
+
+ return 0;
+}
+
+/* We only wait for device setup after most initcalls have run. */
+static int ready_to_wait_for_devices;
+
+/*
+ * On a 5-minute timeout, wait for all devices currently configured. We need
+ * to do this to guarantee that the filesystems and / or network devices
+ * needed for boot are available, before we can allow the boot to proceed.
+ *
+ * This needs to be on a late_initcall, to happen after the frontend device
+ * drivers have been initialised, but before the root fs is mounted.
+ *
+ * A possible improvement here would be to have the tools add a per-device
+ * flag to the store entry, indicating whether it is needed at boot time.
+ * This would allow people who knew what they were doing to accelerate their
+ * boot slightly, but of course needs tools or manual intervention to set up
+ * those flags correctly.
+ */
+static void wait_for_devices(struct xenbus_driver *xendrv)
+{
+ unsigned long start = jiffies;
+ struct device_driver *drv = xendrv ? &xendrv->driver : NULL;
+ unsigned int seconds_waited = 0;
+
+ if (!ready_to_wait_for_devices || !xen_domain())
+ return;
+
+ while (exists_connecting_device(drv)) {
+ if (time_after(jiffies, start + (seconds_waited+5)*HZ)) {
+ if (!seconds_waited)
+ printk(KERN_WARNING "XENBUS: Waiting for "
+ "devices to initialise: ");
+ seconds_waited += 5;
+ printk("%us...", 300 - seconds_waited);
+ if (seconds_waited == 300)
+ break;
+ }
+
+ schedule_timeout_interruptible(HZ/10);
+ }
+
+ if (seconds_waited)
+ printk("\n");
+
+ bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
+ print_device_status);
+}
+
+int __xenbus_register_frontend(struct xenbus_driver *drv,
+ struct module *owner, const char *mod_name)
+{
+ int ret;
+
+ drv->read_otherend_details = read_backend_details;
+
+ ret = xenbus_register_driver_common(drv, &xenbus_frontend,
+ owner, mod_name);
+ if (ret)
+ return ret;
+
+ /* If this driver is loaded as a module wait for devices to attach. */
+ wait_for_devices(drv);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__xenbus_register_frontend);
+
+static int frontend_probe_and_watch(struct notifier_block *notifier,
+ unsigned long event,
+ void *data)
+{
+ /* Enumerate devices in xenstore and watch for changes. */
+ xenbus_probe_devices(&xenbus_frontend);
+ register_xenbus_watch(&fe_watch);
+
+ return NOTIFY_DONE;
+}
+
+
+static int __init xenbus_probe_frontend_init(void)
+{
+ static struct notifier_block xenstore_notifier = {
+ .notifier_call = frontend_probe_and_watch
+ };
+ int err;
+
+ DPRINTK("");
+
+ /* Register ourselves with the kernel bus subsystem */
+ err = bus_register(&xenbus_frontend.bus);
+ if (err)
+ return err;
+
+ register_xenstore_notifier(&xenstore_notifier);
+
+ return 0;
+}
+subsys_initcall(xenbus_probe_frontend_init);
+
+#ifndef MODULE
+static int __init boot_wait_for_devices(void)
+{
+ if (xen_hvm_domain() && !xen_platform_pci_unplug)
+ return -ENODEV;
+
+ ready_to_wait_for_devices = 1;
+ wait_for_devices(NULL);
+ return 0;
+}
+
+late_initcall(boot_wait_for_devices);
+#endif
+
+MODULE_LICENSE("GPL");
int (*remove)(struct xenbus_device *dev);
int (*suspend)(struct xenbus_device *dev, pm_message_t state);
int (*resume)(struct xenbus_device *dev);
- int (*uevent)(struct xenbus_device *, char **, int, char *, int);
+ int (*uevent)(struct xenbus_device *, struct kobj_uevent_env *);
struct device_driver driver;
int (*read_otherend_details)(struct xenbus_device *dev);
int (*is_ready)(struct xenbus_device *dev);
projects / mirror_ubuntu-zesty-kernel.git / commitdiff