--- /dev/null
+/* visorbus_main.c
+ *
+ * Copyright � 2010 - 2013 UNISYS CORPORATION
+ * All rights reserved.
+ *
+ * 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, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ */
+
+#include <linux/uuid.h>
+
+#include "visorbus_private.h"
+#include "businst_attr.h"
+#include "channel_attr.h"
+#include "devmajorminor_attr.h"
+#include "periodic_work.h"
+#include "vbuschannel.h"
+#include "guestlinuxdebug.h"
+#include "vbusdeviceinfo.h"
+/* These forward declarations are required since our drivers are out-of-tree.
+ * The structures referenced are kernel-private and are not in the headers, but
+ * it is impossible to make a functioning bus driver without them.
+ */
+struct subsys_private {
+ struct kset subsys;
+ struct kset *devices_kset;
+
+ struct kset *drivers_kset;
+ struct klist klist_devices;
+ struct klist klist_drivers;
+ struct blocking_notifier_head bus_notifier;
+ unsigned int drivers_autoprobe:1;
+ struct bus_type *bus;
+
+ struct list_head class_interfaces;
+ struct kset glue_dirs;
+ struct mutex class_mutex; /* ignore */
+ struct class *class;
+};
+
+struct bus_type_private {
+ struct kset subsys;
+ struct kset *drivers_kset;
+ struct kset *devices_kset;
+ struct klist klist_devices;
+ struct klist klist_drivers;
+ struct blocking_notifier_head bus_notifier;
+ unsigned int drivers_autoprobe:1;
+ struct bus_type *bus;
+};
+
+#define CURRENT_FILE_PC VISOR_BUS_PC_visorbus_main_c
+#define POLLJIFFIES_TESTWORK 100
+#define POLLJIFFIES_NORMALCHANNEL 10
+
+static int visorbus_uevent(struct device *xdev, struct kobj_uevent_env *env);
+static int visorbus_match(struct device *xdev, struct device_driver *xdrv);
+static void fix_vbus_dev_info(struct visor_device *visordev);
+
+/** This describes the TYPE of bus.
+ * (Don't confuse this with an INSTANCE of the bus.)
+ */
+static struct bus_type visorbus_type = {
+ .name = "visorbus",
+ .match = visorbus_match,
+ .uevent = visorbus_uevent,
+};
+
+static struct delayed_work periodic_work;
+
+/* YES, we need 2 workqueues.
+ * The reason is, workitems on the test queue may need to cancel
+ * workitems on the other queue. You will be in for trouble if you try to
+ * do this with workitems queued on the same workqueue.
+ */
+static struct workqueue_struct *periodic_test_workqueue;
+static struct workqueue_struct *periodic_dev_workqueue;
+static long long bus_count; /** number of bus instances */
+static long long total_devices_created;
+ /** ever-increasing */
+
+static void chipset_bus_create(u32 bus_no);
+static void chipset_bus_destroy(u32 bus_no);
+static void chipset_device_create(u32 bus_no, u32 dev_no);
+static void chipset_device_destroy(u32 bus_no, u32 dev_no);
+static void chipset_device_pause(u32 bus_no, u32 dev_no);
+static void chipset_device_resume(u32 bus_no, u32 dev_no);
+
+/** These functions are implemented herein, and are called by the chipset
+ * driver to notify us about specific events.
+ */
+static struct visorchipset_busdev_notifiers chipset_notifiers = {
+ .bus_create = chipset_bus_create,
+ .bus_destroy = chipset_bus_destroy,
+ .device_create = chipset_device_create,
+ .device_destroy = chipset_device_destroy,
+ .device_pause = chipset_device_pause,
+ .device_resume = chipset_device_resume,
+};
+
+/** These functions are implemented in the chipset driver, and we call them
+ * herein when we want to acknowledge a specific event.
+ */
+static struct visorchipset_busdev_responders chipset_responders;
+
+/* filled in with info about parent chipset driver when we register with it */
+static struct ultra_vbus_deviceinfo chipset_driverinfo;
+/* filled in with info about this driver, wrt it servicing client busses */
+static struct ultra_vbus_deviceinfo clientbus_driverinfo;
+
+/** list of visorbus_devdata structs, linked via .list_all */
+static LIST_HEAD(list_all_bus_instances);
+/** list of visor_device structs, linked via .list_all */
+static LIST_HEAD(list_all_device_instances);
+
+static int
+visorbus_uevent(struct device *xdev, struct kobj_uevent_env *env)
+{
+ if (add_uevent_var(env, "VERSION=%s", VERSION))
+ return -ENOMEM;
+ return 0;
+}
+
+/* This is called automatically upon adding a visor_device (device_add), or
+ * adding a visor_driver (visorbus_register_visor_driver), and returns 1 iff the
+ * provided driver can control the specified device.
+ */
+static int
+visorbus_match(struct device *xdev, struct device_driver *xdrv)
+{
+ uuid_le channel_type;
+ int rc = 0;
+ int i;
+ struct visor_device *dev;
+ struct visor_driver *drv;
+
+ dev = to_visor_device(xdev);
+ drv = to_visor_driver(xdrv);
+ channel_type = visorchannel_get_uuid(dev->visorchannel);
+ if (visorbus_forcematch) {
+ rc = 1;
+ goto away;
+ }
+ if (visorbus_forcenomatch)
+ goto away;
+
+ if (!drv->channel_types)
+ goto away;
+ for (i = 0;
+ (uuid_le_cmp(drv->channel_types[i].guid, NULL_UUID_LE) != 0) ||
+ (drv->channel_types[i].name);
+ i++)
+ if (uuid_le_cmp(drv->channel_types[i].guid,
+ channel_type) == 0) {
+ rc = i + 1;
+ goto away;
+ }
+away:
+ return rc;
+}
+
+/** This is called when device_unregister() is called for the bus device
+ * instance, after all other tasks involved with destroying the device
+ * are complete.
+ */
+static void
+visorbus_release_busdevice(struct device *xdev)
+{
+ struct visorbus_devdata *devdata = dev_get_drvdata(xdev);
+
+ dev_set_drvdata(xdev, NULL);
+ kfree(devdata);
+ kfree(xdev);
+}
+
+/** This is called when device_unregister() is called for each child
+ * device instance.
+ */
+static void
+visorbus_release_device(struct device *xdev)
+{
+ struct visor_device *dev = to_visor_device(xdev);
+
+ if (dev->periodic_work) {
+ visor_periodic_work_destroy(dev->periodic_work);
+ dev->periodic_work = NULL;
+ }
+ if (dev->visorchannel) {
+ visorchannel_destroy(dev->visorchannel);
+ dev->visorchannel = NULL;
+ }
+ kfree(dev);
+}
+
+static const struct sysfs_ops businst_sysfs_ops = {
+ .show = businst_attr_show,
+ .store = businst_attr_store,
+};
+
+static struct kobj_type businst_kobj_type = {
+ .sysfs_ops = &businst_sysfs_ops
+};
+
+static struct kset businstances = { /* should actually be a member of
+ * bus_type */
+};
+
+/* BUS type attributes
+ *
+ * define & implement display of bus attributes under
+ * /sys/bus/visorbus.
+ *
+ */
+
+static ssize_t
+BUSTYPE_ATTR_version(struct bus_type *bus, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%s\n", VERSION);
+}
+
+static struct bus_attribute bustype_attr_version =
+__ATTR(version, S_IRUGO, BUSTYPE_ATTR_version, NULL);
+
+static int
+register_bustype_attributes(void)
+{
+ int rc = 0;
+
+ rc = bus_create_file(&visorbus_type, &bustype_attr_version);
+ if (rc < 0)
+ goto away;
+
+ /* Here we make up for the fact that bus_type does not yet have a
+ * member to keep track of multiple bus instances for a given bus
+ * type. This is useful for stashing properties for each bus
+ * instance.
+ */
+ kobject_set_name(&businstances.kobj, "busses");
+ businstances.kobj.ktype = &businst_kobj_type;
+ businstances.kobj.parent = &visorbus_type.p->subsys.kobj;
+ rc = kset_register(&businstances);
+ if (rc < 0)
+ goto away;
+
+ rc = 0;
+away:
+ return rc;
+}
+
+static void
+unregister_bustype_attributes(void)
+{
+ bus_remove_file(&visorbus_type, &bustype_attr_version);
+ kset_unregister(&businstances);
+}
+
+/* BUS instance attributes
+ *
+ * define & implement display of bus attributes under
+ * /sys/bus/visorbus/busses/visorbus<n>.
+ *
+ * This is a bit hoaky because the kernel does not yet have the infrastructure
+ * to separate bus INSTANCE attributes from bus TYPE attributes...
+ * so we roll our own. See businst.c / businst.h.
+ *
+ */
+
+static ssize_t businst_attr_partition_handle(struct visorbus_devdata *businst,
+ char *buf) {
+ struct visorchipset_bus_info bus_info;
+ int len = 0;
+
+ if (businst && visorchipset_get_bus_info(businst->devno, &bus_info))
+ len = snprintf(buf, PAGE_SIZE,
+ "0x%Lx\n",
+ (unsigned long long)bus_info.partition_handle);
+ return len;
+}
+
+static ssize_t businst_attr_partition_guid(struct visorbus_devdata *businst,
+ char *buf) {
+ struct visorchipset_bus_info bus_info;
+ int len = 0;
+
+ if (businst && visorchipset_get_bus_info(businst->devno, &bus_info))
+ len = snprintf(buf, PAGE_SIZE, "{%pUb}\n",
+ &bus_info.partition_uuid);
+ return len;
+}
+
+static ssize_t businst_attr_partition_name(struct visorbus_devdata *businst,
+ char *buf) {
+ struct visorchipset_bus_info bus_info;
+ int len = 0;
+
+ if (businst &&
+ visorchipset_get_bus_info(businst->devno, &bus_info) &&
+ bus_info.name)
+ len = snprintf(buf, PAGE_SIZE, "%s\n", bus_info.name);
+ return len;
+}
+
+static ssize_t businst_attr_channel_addr(struct visorbus_devdata *businst,
+ char *buf) {
+ struct visorchipset_bus_info bus_info;
+ int len = 0;
+
+ if (businst && visorchipset_get_bus_info(businst->devno, &bus_info))
+ len = snprintf(buf, PAGE_SIZE, "0x%Lx\n", (unsigned long long)
+ bus_info.chan_info.channel_addr);
+ return len;
+}
+
+static ssize_t businst_attr_nchannel_bytes(struct visorbus_devdata *businst,
+ char *buf) {
+ struct visorchipset_bus_info bus_info;
+ int len = 0;
+
+ if (businst && visorchipset_get_bus_info(businst->devno, &bus_info))
+ len = snprintf(buf, PAGE_SIZE, "0x%Lx\n", (unsigned long long)
+ bus_info.chan_info.n_channel_bytes);
+ return len;
+}
+
+static ssize_t businst_attr_channel_id(struct visorbus_devdata *businst,
+ char *buf) {
+ int len = 0;
+
+ if (businst && businst->chan) {
+ visorchannel_id(businst->chan, buf);
+ len = strlen(buf);
+ buf[len++] = '\n';
+ }
+ return len;
+}
+
+static ssize_t businst_attr_client_bus_info(struct visorbus_devdata *businst,
+ char *buf) {
+ struct visorchipset_bus_info bus_info;
+ int i, x, remain = PAGE_SIZE;
+ unsigned long off;
+ char *p = buf;
+ u8 *partition_name;
+ struct ultra_vbus_deviceinfo dev_info;
+
+ partition_name = "";
+ if (businst && businst->chan) {
+ if (visorchipset_get_bus_info(businst->devno, &bus_info) &&
+ bus_info.name)
+ partition_name = bus_info.name;
+ x = snprintf(p, remain,
+ "Client device / client driver info for %s partition (vbus #%d):\n",
+ partition_name, businst->devno);
+ p += x;
+ remain -= x;
+ x = visorchannel_read(businst->chan,
+ offsetof(struct
+ spar_vbus_channel_protocol,
+ chp_info),
+ &dev_info, sizeof(dev_info));
+ if (x >= 0) {
+ x = vbuschannel_devinfo_to_string(&dev_info, p,
+ remain, -1);
+ p += x;
+ remain -= x;
+ }
+ x = visorchannel_read(businst->chan,
+ offsetof(struct
+ spar_vbus_channel_protocol,
+ bus_info),
+ &dev_info, sizeof(dev_info));
+ if (x >= 0) {
+ x = vbuschannel_devinfo_to_string(&dev_info, p,
+ remain, -1);
+ p += x;
+ remain -= x;
+ }
+ off = offsetof(struct spar_vbus_channel_protocol, dev_info);
+ i = 0;
+ while (off + sizeof(dev_info) <=
+ visorchannel_get_nbytes(businst->chan)) {
+ x = visorchannel_read(businst->chan,
+ off, &dev_info, sizeof(dev_info));
+ if (x >= 0) {
+ x = vbuschannel_devinfo_to_string
+ (&dev_info, p, remain, i);
+ p += x;
+ remain -= x;
+ }
+ off += sizeof(dev_info);
+ i++;
+ }
+ }
+ return PAGE_SIZE - remain;
+}
+
+static struct businst_attribute ba_partition_handle =
+ __ATTR(partition_handle, S_IRUGO, businst_attr_partition_handle, NULL);
+static struct businst_attribute ba_partition_guid =
+ __ATTR(partition_guid, S_IRUGO, businst_attr_partition_guid, NULL);
+static struct businst_attribute ba_partition_name =
+ __ATTR(partition_name, S_IRUGO, businst_attr_partition_name, NULL);
+static struct businst_attribute ba_channel_addr =
+ __ATTR(channel_addr, S_IRUGO, businst_attr_channel_addr, NULL);
+static struct businst_attribute ba_nchannel_bytes =
+ __ATTR(nchannel_bytes, S_IRUGO, businst_attr_nchannel_bytes, NULL);
+static struct businst_attribute ba_channel_id =
+ __ATTR(channel_id, S_IRUGO, businst_attr_channel_id, NULL);
+static struct businst_attribute ba_client_bus_info =
+ __ATTR(client_bus_info, S_IRUGO, businst_attr_client_bus_info, NULL);
+
+static int
+register_businst_attributes(struct visorbus_devdata *businst)
+{
+ int rc = 0;
+
+ businst->kobj.kset = &businstances; /* identify parent sysfs dir */
+ rc = kobject_init_and_add(&businst->kobj, &businst_kobj_type,
+ NULL, "visorbus%d", businst->devno);
+ if (rc < 0)
+ goto away;
+
+ rc = businst_create_file(businst, &ba_partition_handle);
+ if (rc < 0)
+ goto away;
+
+ rc = businst_create_file(businst, &ba_partition_guid);
+ if (rc < 0)
+ goto away;
+
+ rc = businst_create_file(businst, &ba_partition_name);
+ if (rc < 0)
+ goto away;
+
+ rc = businst_create_file(businst, &ba_channel_addr);
+ if (rc < 0)
+ goto away;
+
+ rc = businst_create_file(businst, &ba_nchannel_bytes);
+ if (rc < 0)
+ goto away;
+
+ rc = businst_create_file(businst, &ba_channel_id);
+ if (rc < 0)
+ goto away;
+
+ rc = businst_create_file(businst, &ba_client_bus_info);
+ if (rc < 0)
+ goto away;
+
+ kobject_uevent(&businst->kobj, KOBJ_ADD);
+
+ rc = 0;
+away:
+ return rc;
+}
+
+static void
+unregister_businst_attributes(struct visorbus_devdata *businst)
+{
+ businst_remove_file(businst, &ba_partition_handle);
+ businst_remove_file(businst, &ba_partition_guid);
+ businst_remove_file(businst, &ba_partition_name);
+ businst_remove_file(businst, &ba_channel_addr);
+ businst_remove_file(businst, &ba_nchannel_bytes);
+ businst_remove_file(businst, &ba_channel_id);
+ businst_remove_file(businst, &ba_client_bus_info);
+ kobject_put(&businst->kobj);
+}
+
+/* DRIVER attributes
+ *
+ * define & implement display of driver attributes under
+ * /sys/bus/visorbus/drivers/<drivername>.
+ *
+ */
+
+static ssize_t
+DRIVER_ATTR_version(struct device_driver *xdrv, char *buf)
+{
+ struct visor_driver *drv = to_visor_driver(xdrv);
+
+ return snprintf(buf, PAGE_SIZE, "%s\n", drv->version);
+}
+
+static int
+register_driver_attributes(struct visor_driver *drv)
+{
+ int rc;
+ struct driver_attribute version =
+ __ATTR(version, S_IRUGO, DRIVER_ATTR_version, NULL);
+ drv->version_attr = version;
+ rc = driver_create_file(&drv->driver, &drv->version_attr);
+ return rc;
+}
+
+static void
+unregister_driver_attributes(struct visor_driver *drv)
+{
+ driver_remove_file(&drv->driver, &drv->version_attr);
+}
+
+/* DEVICE attributes
+ *
+ * define & implement display of device attributes under
+ * /sys/bus/visorbus/devices/<devicename>.
+ *
+ */
+
+#define DEVATTR(nam, func) { \
+ .attr = { .name = __stringify(nam), \
+ .mode = 0444, \
+ .owner = THIS_MODULE }, \
+ .show = func, \
+}
+
+static struct device_attribute visor_device_attrs[] = {
+ /* DEVATTR(channel_nbytes, DEVICE_ATTR_channel_nbytes), */
+ __ATTR_NULL
+};
+
+static void
+dev_periodic_work(void *xdev)
+{
+ struct visor_device *dev = (struct visor_device *)xdev;
+ struct visor_driver *drv = to_visor_driver(dev->device.driver);
+
+ down(&dev->visordriver_callback_lock);
+ if (drv->channel_interrupt)
+ drv->channel_interrupt(dev);
+ up(&dev->visordriver_callback_lock);
+ if (!visor_periodic_work_nextperiod(dev->periodic_work))
+ put_device(&dev->device);
+}
+
+static void
+dev_start_periodic_work(struct visor_device *dev)
+{
+ if (dev->being_removed)
+ return;
+ /* now up by at least 2 */
+ get_device(&dev->device);
+ if (!visor_periodic_work_start(dev->periodic_work))
+ put_device(&dev->device);
+}
+
+static void
+dev_stop_periodic_work(struct visor_device *dev)
+{
+ if (visor_periodic_work_stop(dev->periodic_work))
+ put_device(&dev->device);
+}
+
+/** This is called automatically upon adding a visor_device (device_add), or
+ * adding a visor_driver (visorbus_register_visor_driver), but only after
+ * visorbus_match has returned 1 to indicate a successful match between
+ * driver and device.
+ */
+static int
+visordriver_probe_device(struct device *xdev)
+{
+ int rc;
+ struct visor_driver *drv;
+ struct visor_device *dev;
+
+ drv = to_visor_driver(xdev->driver);
+ dev = to_visor_device(xdev);
+ down(&dev->visordriver_callback_lock);
+ dev->being_removed = FALSE;
+ /*
+ * ensure that the dev->being_removed flag is cleared before
+ * we start the probe
+ */
+ wmb();
+ get_device(&dev->device);
+ if (!drv->probe) {
+ up(&dev->visordriver_callback_lock);
+ rc = -1;
+ goto away;
+ }
+ rc = drv->probe(dev);
+ if (rc < 0)
+ goto away;
+
+ fix_vbus_dev_info(dev);
+ up(&dev->visordriver_callback_lock);
+ rc = 0;
+away:
+ if (rc != 0)
+ put_device(&dev->device);
+ /* We could get here more than once if the child driver module is
+ * unloaded and re-loaded while devices are present. That's why we
+ * need a flag to be sure that we only respond to the device_create
+ * once. We cannot respond to the device_create prior to here,
+ * because until we call drv->probe() above, the channel has not been
+ * initialized.
+ */
+ if (!dev->responded_to_device_create) {
+ dev->responded_to_device_create = TRUE;
+ if (chipset_responders.device_create)
+ (*chipset_responders.device_create)(dev->chipset_bus_no,
+ dev->chipset_dev_no,
+ rc);
+ }
+ return rc;
+}
+
+/** This is called when device_unregister() is called for each child device
+ * instance, to notify the appropriate visorbus_driver that the device is
+ * going away, and to decrease the reference count of the device.
+ */
+static int
+visordriver_remove_device(struct device *xdev)
+{
+ int rc = 0;
+ struct visor_device *dev;
+ struct visor_driver *drv;
+
+ dev = to_visor_device(xdev);
+ drv = to_visor_driver(xdev->driver);
+ down(&dev->visordriver_callback_lock);
+ dev->being_removed = TRUE;
+ /*
+ * ensure that the dev->being_removed flag is set before we start the
+ * actual removal
+ */
+ wmb();
+ if (drv) {
+ if (drv->remove)
+ drv->remove(dev);
+ }
+ up(&dev->visordriver_callback_lock);
+ dev_stop_periodic_work(dev);
+ devmajorminor_remove_all_files(dev);
+
+ put_device(&dev->device);
+
+ return rc;
+}
+
+/** A particular type of visor driver calls this function to register
+ * the driver. The caller MUST fill in the following fields within the
+ * #drv structure:
+ * name, version, owner, channel_types, probe, remove
+ *
+ * Here's how the whole Linux bus / driver / device model works.
+ *
+ * At system start-up, the visorbus kernel module is loaded, which registers
+ * visorbus_type as a bus type, using bus_register().
+ *
+ * All kernel modules that support particular device types on a
+ * visorbus bus are loaded. Each of these kernel modules calls
+ * visorbus_register_visor_driver() in their init functions, passing a
+ * visor_driver struct. visorbus_register_visor_driver() in turn calls
+ * register_driver(&visor_driver.driver). This .driver member is
+ * initialized with generic methods (like probe), whose sole responsibility
+ * is to act as a broker for the real methods, which are within the
+ * visor_driver struct. (This is the way the subclass behavior is
+ * implemented, since visor_driver is essentially a subclass of the
+ * generic driver.) Whenever a driver_register() happens, core bus code in
+ * the kernel does (see device_attach() in drivers/base/dd.c):
+ *
+ * for each dev associated with the bus (the bus that driver is on) that
+ * does not yet have a driver
+ * if bus.match(dev,newdriver) == yes_matched ** .match specified
+ * ** during bus_register().
+ * newdriver.probe(dev) ** for visor drivers, this will call
+ * ** the generic driver.probe implemented in visorbus.c,
+ * ** which in turn calls the probe specified within the
+ * ** struct visor_driver (which was specified by the
+ * ** actual device driver as part of
+ * ** visorbus_register_visor_driver()).
+ *
+ * The above dance also happens when a new device appears.
+ * So the question is, how are devices created within the system?
+ * Basically, just call device_add(dev). See pci_bus_add_devices().
+ * pci_scan_device() shows an example of how to build a device struct. It
+ * returns the newly-created struct to pci_scan_single_device(), who adds it
+ * to the list of devices at PCIBUS.devices. That list of devices is what
+ * is traversed by pci_bus_add_devices().
+ *
+ */
+int visorbus_register_visor_driver(struct visor_driver *drv)
+{
+ int rc = 0;
+
+ drv->driver.name = drv->name;
+ drv->driver.bus = &visorbus_type;
+ drv->driver.probe = visordriver_probe_device;
+ drv->driver.remove = visordriver_remove_device;
+ drv->driver.owner = drv->owner;
+
+ /* driver_register does this:
+ * bus_add_driver(drv)
+ * ->if (drv.bus) ** (bus_type) **
+ * driver_attach(drv)
+ * for each dev with bus type of drv.bus
+ * if (!dev.drv) ** no driver assigned yet **
+ * if (bus.match(dev,drv)) [visorbus_match]
+ * dev.drv = drv
+ * if (!drv.probe(dev)) [visordriver_probe_device]
+ * dev.drv = NULL
+ */
+
+ rc = driver_register(&drv->driver);
+ if (rc < 0)
+ return rc;
+ rc = register_driver_attributes(drv);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(visorbus_register_visor_driver);
+
+/** A particular type of visor driver calls this function to unregister
+ * the driver, i.e., within its module_exit function.
+ */
+void
+visorbus_unregister_visor_driver(struct visor_driver *drv)
+{
+ unregister_driver_attributes(drv);
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(visorbus_unregister_visor_driver);
+
+int
+visorbus_read_channel(struct visor_device *dev, unsigned long offset,
+ void *dest, unsigned long nbytes)
+{
+ return visorchannel_read(dev->visorchannel, offset, dest, nbytes);
+}
+EXPORT_SYMBOL_GPL(visorbus_read_channel);
+
+int
+visorbus_write_channel(struct visor_device *dev, unsigned long offset,
+ void *src, unsigned long nbytes)
+{
+ return visorchannel_write(dev->visorchannel, offset, src, nbytes);
+}
+EXPORT_SYMBOL_GPL(visorbus_write_channel);
+
+int
+visorbus_clear_channel(struct visor_device *dev, unsigned long offset, u8 ch,
+ unsigned long nbytes)
+{
+ return visorchannel_clear(dev->visorchannel, offset, ch, nbytes);
+}
+EXPORT_SYMBOL_GPL(visorbus_clear_channel);
+
+int
+visorbus_registerdevnode(struct visor_device *dev,
+ const char *name, int major, int minor)
+{
+ return devmajorminor_create_file(dev, name, major, minor);
+}
+EXPORT_SYMBOL_GPL(visorbus_registerdevnode);
+
+/** We don't really have a real interrupt, so for now we just call the
+ * interrupt function periodically...
+ */
+void
+visorbus_enable_channel_interrupts(struct visor_device *dev)
+{
+ dev_start_periodic_work(dev);
+}
+EXPORT_SYMBOL_GPL(visorbus_enable_channel_interrupts);
+
+void
+visorbus_disable_channel_interrupts(struct visor_device *dev)
+{
+ dev_stop_periodic_work(dev);
+}
+EXPORT_SYMBOL_GPL(visorbus_disable_channel_interrupts);
+
+/** This is how everything starts from the device end.
+ * This function is called when a channel first appears via a ControlVM
+ * message. In response, this function allocates a visor_device to
+ * correspond to the new channel, and attempts to connect it the appropriate
+ * driver. If the appropriate driver is found, the visor_driver.probe()
+ * function for that driver will be called, and will be passed the new
+ * visor_device that we just created.
+ *
+ * It's ok if the appropriate driver is not yet loaded, because in that case
+ * the new device struct will just stick around in the bus' list of devices.
+ * When the appropriate driver calls visorbus_register_visor_driver(), the
+ * visor_driver.probe() for the new driver will be called with the new
+ * device.
+ */
+static int
+create_visor_device(struct visorbus_devdata *devdata,
+ unsigned long chipset_bus_no, unsigned long chipset_dev_no,
+ struct visorchipset_channel_info chan_info,
+ u64 partition_handle)
+{
+ int rc = -1;
+ struct visorchannel *visorchannel = NULL;
+ struct visor_device *dev = NULL;
+ bool gotten = FALSE, registered1 = FALSE, registered2 = FALSE;
+
+ POSTCODE_LINUX_4(DEVICE_CREATE_ENTRY_PC, chipset_dev_no, chipset_bus_no,
+ POSTCODE_SEVERITY_INFO);
+ /* prepare chan_hdr (abstraction to read/write channel memory) */
+ visorchannel = visorchannel_create(chan_info.channel_addr,
+ (unsigned long)
+ chan_info.n_channel_bytes,
+ chan_info.channel_type_uuid);
+ if (!visorchannel) {
+ POSTCODE_LINUX_3(DEVICE_CREATE_FAILURE_PC, chipset_dev_no,
+ DIAG_SEVERITY_ERR);
+ goto away;
+ }
+ dev = kmalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev) {
+ POSTCODE_LINUX_3(DEVICE_CREATE_FAILURE_PC, chipset_dev_no,
+ DIAG_SEVERITY_ERR);
+ goto away;
+ }
+
+ memset(dev, 0, sizeof(struct visor_device));
+ dev->visorchannel = visorchannel;
+ dev->channel_type_guid = chan_info.channel_type_uuid;
+ dev->channel_bytes = chan_info.n_channel_bytes;
+ dev->chipset_bus_no = chipset_bus_no;
+ dev->chipset_dev_no = chipset_dev_no;
+ dev->device.parent = devdata->dev;
+ sema_init(&dev->visordriver_callback_lock, 1); /* unlocked */
+ dev->device.bus = &visorbus_type;
+ device_initialize(&dev->device);
+ dev->device.release = visorbus_release_device;
+ /* keep a reference just for us (now 2) */
+ get_device(&dev->device);
+ gotten = TRUE;
+ dev->periodic_work =
+ visor_periodic_work_create(POLLJIFFIES_NORMALCHANNEL,
+ periodic_dev_workqueue,
+ dev_periodic_work,
+ dev, dev_name(&dev->device));
+ if (!dev->periodic_work) {
+ POSTCODE_LINUX_3(DEVICE_CREATE_FAILURE_PC, chipset_dev_no,
+ DIAG_SEVERITY_ERR);
+ goto away;
+ }
+
+ /* bus_id must be a unique name with respect to this bus TYPE
+ * (NOT bus instance). That's why we need to include the bus
+ * number within the name.
+ */
+ dev_set_name(&dev->device, "vbus%lu:dev%lu",
+ chipset_bus_no, chipset_dev_no);
+
+ /* device_add does this:
+ * bus_add_device(dev)
+ * ->device_attach(dev)
+ * ->for each driver drv registered on the bus that dev is on
+ * if (dev.drv) ** device already has a driver **
+ * ** not sure we could ever get here... **
+ * else
+ * if (bus.match(dev,drv)) [visorbus_match]
+ * dev.drv = drv
+ * if (!drv.probe(dev)) [visordriver_probe_device]
+ * dev.drv = NULL
+ *
+ * Note that device_add does NOT fail if no driver failed to
+ * claim the device. The device will be linked onto
+ * bus_type.klist_devices regardless (use bus_for_each_dev).
+ */
+ rc = device_add(&dev->device);
+ if (rc < 0) {
+ POSTCODE_LINUX_3(DEVICE_ADD_PC, chipset_bus_no,
+ DIAG_SEVERITY_ERR);
+ goto away;
+ }
+
+ /* note: device_register is simply device_initialize + device_add */
+ rc = register_channel_attributes(dev);
+ if (rc < 0) {
+ POSTCODE_LINUX_3(DEVICE_REGISTER_FAILURE_PC, chipset_dev_no,
+ DIAG_SEVERITY_ERR);
+ goto away;
+ }
+
+ registered1 = TRUE;
+
+ rc = register_devmajorminor_attributes(dev);
+ if (rc < 0) {
+ POSTCODE_LINUX_3(DEVICE_REGISTER_FAILURE_PC, chipset_dev_no,
+ DIAG_SEVERITY_ERR);
+ goto away;
+ }
+
+ registered2 = TRUE;
+ rc = 0;
+
+away:
+ if (rc < 0) {
+ if (registered2)
+ unregister_devmajorminor_attributes(dev);
+ if (registered1)
+ unregister_channel_attributes(dev);
+ if (gotten)
+ put_device(&dev->device);
+ if (visorchannel)
+ visorchannel_destroy(visorchannel);
+ kfree(dev);
+ } else {
+ total_devices_created++;
+ list_add_tail(&dev->list_all, &list_all_device_instances);
+ }
+ return rc;
+}
+
+static void
+remove_visor_device(struct visor_device *dev)
+{
+ list_del(&dev->list_all);
+ unregister_devmajorminor_attributes(dev);
+ unregister_channel_attributes(dev);
+ put_device(&dev->device);
+ device_unregister(&dev->device);
+}
+
+static struct visor_device *
+find_visor_device_by_channel(HOSTADDRESS channel_physaddr)
+{
+ struct list_head *listentry, *listtmp;
+
+ list_for_each_safe(listentry, listtmp, &list_all_device_instances) {
+ struct visor_device *dev = list_entry(listentry,
+ struct visor_device,
+ list_all);
+ if (visorchannel_get_physaddr(dev->visorchannel) ==
+ channel_physaddr)
+ return dev;
+ }
+ return NULL;
+}
+
+static int
+init_vbus_channel(struct visorchannel *chan)
+{
+ int rc = -1;
+ unsigned long allocated_bytes = visorchannel_get_nbytes(chan);
+ struct spar_vbus_channel_protocol *x =
+ kmalloc(sizeof(struct spar_vbus_channel_protocol),
+ GFP_KERNEL);
+
+ POSTCODE_LINUX_3(VBUS_CHANNEL_ENTRY_PC, rc, POSTCODE_SEVERITY_INFO);
+
+ if (x) {
+ POSTCODE_LINUX_2(MALLOC_FAILURE_PC, POSTCODE_SEVERITY_ERR);
+ goto away;
+ }
+ if (visorchannel_clear(chan, 0, 0, allocated_bytes) < 0) {
+ POSTCODE_LINUX_2(VBUS_CHANNEL_FAILURE_PC,
+ POSTCODE_SEVERITY_ERR);
+ goto away;
+ }
+ if (visorchannel_read
+ (chan, 0, x, sizeof(struct spar_vbus_channel_protocol)) < 0) {
+ POSTCODE_LINUX_2(VBUS_CHANNEL_FAILURE_PC,
+ POSTCODE_SEVERITY_ERR);
+ goto away;
+ }
+ if (!SPAR_VBUS_CHANNEL_OK_SERVER(allocated_bytes)) {
+ POSTCODE_LINUX_2(VBUS_CHANNEL_FAILURE_PC,
+ POSTCODE_SEVERITY_ERR);
+ goto away;
+ }
+
+ if (visorchannel_write
+ (chan, 0, x, sizeof(struct spar_vbus_channel_protocol)) < 0) {
+ POSTCODE_LINUX_3(VBUS_CHANNEL_FAILURE_PC, chan,
+ POSTCODE_SEVERITY_ERR);
+ goto away;
+ }
+
+ POSTCODE_LINUX_3(VBUS_CHANNEL_EXIT_PC, chan, POSTCODE_SEVERITY_INFO);
+ rc = 0;
+
+away:
+ kfree(x);
+ x = NULL;
+ return rc;
+}
+
+static int
+get_vbus_header_info(struct visorchannel *chan,
+ struct spar_vbus_headerinfo *hdr_info)
+{
+ int rc = -1;
+
+ if (!SPAR_VBUS_CHANNEL_OK_CLIENT(visorchannel_get_header(chan)))
+ goto away;
+ if (visorchannel_read(chan, sizeof(struct channel_header), hdr_info,
+ sizeof(*hdr_info)) < 0) {
+ goto away;
+ }
+ if (hdr_info->struct_bytes < sizeof(struct spar_vbus_headerinfo))
+ goto away;
+ if (hdr_info->device_info_struct_bytes <
+ sizeof(struct ultra_vbus_deviceinfo)) {
+ goto away;
+ }
+ rc = 0;
+away:
+ return rc;
+}
+
+/* Write the contents of <info> to the struct
+ * spar_vbus_channel_protocol.chp_info. */
+
+static int
+write_vbus_chp_info(struct visorchannel *chan,
+ struct spar_vbus_headerinfo *hdr_info,
+ struct ultra_vbus_deviceinfo *info)
+{
+ int off = sizeof(struct channel_header) + hdr_info->chp_info_offset;
+
+ if (hdr_info->chp_info_offset == 0)
+ return -1;
+
+ if (visorchannel_write(chan, off, info, sizeof(*info)) < 0)
+ return -1;
+ return 0;
+}
+
+/* Write the contents of <info> to the struct
+ * spar_vbus_channel_protocol.bus_info. */
+
+static int
+write_vbus_bus_info(struct visorchannel *chan,
+ struct spar_vbus_headerinfo *hdr_info,
+ struct ultra_vbus_deviceinfo *info)
+{
+ int off = sizeof(struct channel_header) + hdr_info->bus_info_offset;
+
+ if (hdr_info->bus_info_offset == 0)
+ return -1;
+
+ if (visorchannel_write(chan, off, info, sizeof(*info)) < 0)
+ return -1;
+ return 0;
+}
+
+/* Write the contents of <info> to the
+ * struct spar_vbus_channel_protocol.dev_info[<devix>].
+ */
+static int
+write_vbus_dev_info(struct visorchannel *chan,
+ struct spar_vbus_headerinfo *hdr_info,
+ struct ultra_vbus_deviceinfo *info, int devix)
+{
+ int off =
+ (sizeof(struct channel_header) + hdr_info->dev_info_offset) +
+ (hdr_info->device_info_struct_bytes * devix);
+
+ if (hdr_info->dev_info_offset == 0)
+ return -1;
+
+ if (visorchannel_write(chan, off, info, sizeof(*info)) < 0)
+ return -1;
+ return 0;
+}
+
+/* For a child device just created on a client bus, fill in
+ * information about the driver that is controlling this device into
+ * the the appropriate slot within the vbus channel of the bus
+ * instance.
+ */
+static void
+fix_vbus_dev_info(struct visor_device *visordev)
+{
+ int i;
+ struct visorchipset_bus_info bus_info;
+ struct visorbus_devdata *devdata = NULL;
+ struct visor_driver *visordrv;
+ int bus_no = visordev->chipset_bus_no;
+ int dev_no = visordev->chipset_dev_no;
+ struct ultra_vbus_deviceinfo dev_info;
+ const char *chan_type_name = NULL;
+
+ if (!visordev->device.driver)
+ return;
+
+ visordrv = to_visor_driver(visordev->device.driver);
+ if (!visorchipset_get_bus_info(bus_no, &bus_info))
+ return;
+
+ devdata = (struct visorbus_devdata *)(bus_info.bus_driver_context);
+ if (!devdata)
+ return;
+
+ if (!devdata->vbus_valid)
+ return;
+
+ /* Within the list of device types (by GUID) that the driver
+ * says it supports, find out which one of those types matches
+ * the type of this device, so that we can include the device
+ * type name
+ */
+ for (i = 0; visordrv->channel_types[i].name; i++) {
+ if (STRUCTSEQUAL(visordrv->channel_types[i].guid,
+ visordev->channel_type_guid)) {
+ chan_type_name = visordrv->channel_types[i].name;
+ break;
+ }
+ }
+
+ bus_device_info_init(&dev_info, chan_type_name,
+ visordrv->name, visordrv->version,
+ visordrv->vertag);
+ write_vbus_dev_info(devdata->chan,
+ &devdata->vbus_hdr_info, &dev_info, dev_no);
+
+ /* Re-write bus+chipset info, because it is possible that this
+ * was previously written by our evil counterpart, virtpci.
+ */
+ write_vbus_chp_info(devdata->chan, &devdata->vbus_hdr_info,
+ &chipset_driverinfo);
+ write_vbus_bus_info(devdata->chan, &devdata->vbus_hdr_info,
+ &clientbus_driverinfo);
+}
+
+/** Create a device instance for the visor bus itself.
+ */
+static struct visorbus_devdata *
+create_bus_instance(int id)
+{
+ struct visorbus_devdata *rc = NULL;
+ struct visorbus_devdata *devdata = NULL;
+ struct device *dev;
+ struct visorchipset_bus_info bus_info;
+
+ POSTCODE_LINUX_2(BUS_CREATE_ENTRY_PC, POSTCODE_SEVERITY_INFO);
+ dev = kmalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev) {
+ POSTCODE_LINUX_2(MALLOC_FAILURE_PC, POSTCODE_SEVERITY_ERR);
+ rc = NULL;
+ goto away;
+ }
+ memset(dev, 0, sizeof(struct device));
+ dev_set_name(dev, "visorbus%d", id);
+ dev->release = visorbus_release_busdevice;
+ if (device_register(dev) < 0) {
+ POSTCODE_LINUX_3(DEVICE_CREATE_FAILURE_PC, id,
+ POSTCODE_SEVERITY_ERR);
+ rc = NULL;
+ goto away;
+ }
+ devdata = kmalloc(sizeof(*devdata), GFP_KERNEL);
+ if (!devdata) {
+ POSTCODE_LINUX_2(MALLOC_FAILURE_PC, POSTCODE_SEVERITY_ERR);
+ rc = NULL;
+ goto away;
+ }
+ memset(devdata, 0, sizeof(struct visorbus_devdata));
+ devdata->devno = id;
+ devdata->dev = dev;
+ if ((visorchipset_get_bus_info(id, &bus_info)) &&
+ (bus_info.chan_info.channel_addr > 0) &&
+ (bus_info.chan_info.n_channel_bytes > 0)) {
+ HOSTADDRESS channel_addr = bus_info.chan_info.channel_addr;
+ unsigned long n_channel_bytes =
+ (unsigned long)
+ bus_info.chan_info.n_channel_bytes;
+ uuid_le channel_type_guid =
+ bus_info.chan_info.channel_type_uuid;
+
+ devdata->chan = visorchannel_create(channel_addr,
+ n_channel_bytes,
+ channel_type_guid);
+ if (!devdata->chan) {
+ POSTCODE_LINUX_3(DEVICE_CREATE_FAILURE_PC, channel_addr,
+ POSTCODE_SEVERITY_ERR);
+ } else {
+ if (bus_info.flags.server) {
+ init_vbus_channel(devdata->chan);
+ } else {
+ if (get_vbus_header_info(devdata->chan,
+ &devdata->
+ vbus_hdr_info) >= 0) {
+ devdata->vbus_valid = TRUE;
+ write_vbus_chp_info(devdata->chan,
+ &devdata->
+ vbus_hdr_info,
+ &chipset_driverinfo
+ );
+ write_vbus_bus_info(devdata->chan,
+ &devdata->
+ vbus_hdr_info,
+ &clientbus_driverinfo);
+ }
+ }
+ }
+ }
+ register_businst_attributes(devdata);
+ bus_count++;
+ list_add_tail(&devdata->list_all, &list_all_bus_instances);
+ if (id == 0)
+ devdata = devdata; /* for testing ONLY */
+ dev_set_drvdata(dev, devdata);
+ rc = devdata;
+away:
+ return rc;
+}
+
+/** Remove a device instance for the visor bus itself.
+ */
+static void
+remove_bus_instance(struct visorbus_devdata *devdata)
+{
+ /* Note that this will result in the release method for
+ * devdata->dev being called, which will call
+ * visorbus_release_busdevice(). This has something to do with
+ * the put_device() done in device_unregister(), but I have never
+ * successfully been able to trace thru the code to see where/how
+ * release() gets called. But I know it does.
+ */
+ unregister_businst_attributes(devdata);
+ bus_count--;
+ if (devdata->chan) {
+ visorchannel_destroy(devdata->chan);
+ devdata->chan = NULL;
+ }
+ list_del(&devdata->list_all);
+ device_unregister(devdata->dev);
+}
+
+/** Create and register the one-and-only one instance of
+ * the visor bus type (visorbus_type).
+ */
+static int
+create_bus_type(void)
+{
+ int rc = 0;
+
+ visorbus_type.dev_attrs = visor_device_attrs;
+ rc = bus_register(&visorbus_type);
+ if (rc < 0)
+ return rc;
+
+ rc = register_bustype_attributes();
+ return rc;
+}
+
+/** Remove the one-and-only one instance of the visor bus type (visorbus_type).
+ */
+static void
+remove_bus_type(void)
+{
+ unregister_bustype_attributes();
+ bus_unregister(&visorbus_type);
+}
+
+/** Remove all child visor bus device instances.
+ */
+static void
+remove_all_visor_devices(void)
+{
+ struct list_head *listentry, *listtmp;
+
+ list_for_each_safe(listentry, listtmp, &list_all_device_instances) {
+ struct visor_device *dev = list_entry(listentry,
+ struct visor_device,
+ list_all);
+ remove_visor_device(dev);
+ }
+}
+
+static bool entered_testing_mode = FALSE;
+static struct visorchipset_channel_info test_channel_infos[MAXDEVICETEST];
+static unsigned long test_bus_nos[MAXDEVICETEST];
+static unsigned long test_dev_nos[MAXDEVICETEST];
+
+static void
+chipset_bus_create(u32 bus_no)
+{
+ struct visorchipset_bus_info bus_info;
+ struct visorbus_devdata *devdata;
+ int rc = -1;
+
+ POSTCODE_LINUX_3(BUS_CREATE_ENTRY_PC, bus_no, POSTCODE_SEVERITY_INFO);
+ if (!visorchipset_get_bus_info(bus_no, &bus_info))
+ goto away;
+ devdata = create_bus_instance(bus_no);
+ if (!devdata)
+ goto away;
+ if (!visorchipset_set_bus_context(bus_no, devdata))
+ goto away;
+ POSTCODE_LINUX_3(BUS_CREATE_EXIT_PC, bus_no, POSTCODE_SEVERITY_INFO);
+ rc = 0;
+away:
+ if (rc < 0) {
+ POSTCODE_LINUX_3(BUS_CREATE_FAILURE_PC, bus_no,
+ POSTCODE_SEVERITY_ERR);
+ return;
+ }
+ POSTCODE_LINUX_3(CHIPSET_INIT_SUCCESS_PC, bus_no,
+ POSTCODE_SEVERITY_INFO);
+ if (chipset_responders.bus_create)
+ (*chipset_responders.bus_create) (bus_no, rc);
+}
+
+static void
+chipset_bus_destroy(u32 bus_no)
+{
+ struct visorchipset_bus_info bus_info;
+ struct visorbus_devdata *devdata;
+ int rc = -1;
+
+ if (!visorchipset_get_bus_info(bus_no, &bus_info))
+ goto away;
+ devdata = (struct visorbus_devdata *)(bus_info.bus_driver_context);
+ if (!devdata)
+ goto away;
+ remove_bus_instance(devdata);
+ if (!visorchipset_set_bus_context(bus_no, NULL))
+ goto away;
+ rc = 0;
+away:
+ if (rc < 0)
+ return;
+ if (chipset_responders.bus_destroy)
+ (*chipset_responders.bus_destroy)(bus_no, rc);
+}
+
+static void
+chipset_device_create(u32 bus_no, u32 dev_no)
+{
+ struct visorchipset_device_info dev_info;
+ struct visorchipset_bus_info bus_info;
+ struct visorbus_devdata *devdata = NULL;
+ int rc = -1;
+
+ POSTCODE_LINUX_4(DEVICE_CREATE_ENTRY_PC, dev_no, bus_no,
+ POSTCODE_SEVERITY_INFO);
+
+ if (entered_testing_mode)
+ return;
+ if (!visorchipset_get_device_info(bus_no, dev_no, &dev_info))
+ goto away;
+ if (!visorchipset_get_bus_info(bus_no, &bus_info))
+ goto away;
+ if (visorbus_devicetest)
+ if (total_devices_created < MAXDEVICETEST) {
+ test_channel_infos[total_devices_created] =
+ dev_info.chan_info;
+ test_bus_nos[total_devices_created] = bus_no;
+ test_dev_nos[total_devices_created] = dev_no;
+ }
+ POSTCODE_LINUX_4(DEVICE_CREATE_EXIT_PC, dev_no, bus_no,
+ POSTCODE_SEVERITY_INFO);
+ rc = 0;
+away:
+ if (rc < 0) {
+ POSTCODE_LINUX_4(DEVICE_CREATE_FAILURE_PC, dev_no, bus_no,
+ POSTCODE_SEVERITY_ERR);
+ return;
+ }
+ devdata = (struct visorbus_devdata *)(bus_info.bus_driver_context);
+ rc = create_visor_device(devdata, bus_no, dev_no,
+ dev_info.chan_info, bus_info.partition_handle);
+ POSTCODE_LINUX_4(DEVICE_CREATE_SUCCESS_PC, dev_no, bus_no,
+ POSTCODE_SEVERITY_INFO);
+ if (rc < 0)
+ if (chipset_responders.device_create)
+ (*chipset_responders.device_create)(bus_no, dev_no, rc);
+}
+
+static void
+chipset_device_destroy(u32 bus_no, u32 dev_no)
+{
+ struct visorchipset_device_info dev_info;
+ struct visor_device *dev;
+ int rc = -1;
+
+ if (entered_testing_mode)
+ return;
+ if (!visorchipset_get_device_info(bus_no, dev_no, &dev_info))
+ goto away;
+ dev = find_visor_device_by_channel(dev_info.chan_info.channel_addr);
+ if (!dev)
+ goto away;
+ rc = 0;
+away:
+ if (rc < 0)
+ return;
+
+ if (chipset_responders.device_destroy)
+ (*chipset_responders.device_destroy) (bus_no, dev_no, rc);
+ remove_visor_device(dev);
+}
+
+/* This is the callback function specified for a function driver, to
+ * be called when a pending "pause device" operation has been
+ * completed.
+ */
+static void
+pause_state_change_complete(struct visor_device *dev, int status)
+{
+ if (!dev->pausing)
+ return;
+
+ dev->pausing = FALSE;
+ if (!chipset_responders.device_pause) /* this can never happen! */
+ return;
+
+ /* Notify the chipset driver that the pause is complete, which
+ * will presumably want to send some sort of response to the
+ * initiator. */
+ (*chipset_responders.device_pause) (dev->chipset_bus_no,
+ dev->chipset_dev_no, status);
+}
+
+/* This is the callback function specified for a function driver, to
+ * be called when a pending "resume device" operation has been
+ * completed.
+ */
+static void
+resume_state_change_complete(struct visor_device *dev, int status)
+{
+ if (!dev->resuming)
+ return;
+
+ dev->resuming = FALSE;
+ if (!chipset_responders.device_resume) /* this can never happen! */
+ return;
+
+ /* Notify the chipset driver that the resume is complete,
+ * which will presumably want to send some sort of response to
+ * the initiator. */
+ (*chipset_responders.device_resume) (dev->chipset_bus_no,
+ dev->chipset_dev_no, status);
+}
+
+/* Tell the subordinate function driver for a specific device to pause
+ * or resume that device. Result is returned asynchronously via a
+ * callback function.
+ */
+static void
+initiate_chipset_device_pause_resume(u32 bus_no, u32 dev_no, bool is_pause)
+{
+ struct visorchipset_device_info dev_info;
+ struct visor_device *dev = NULL;
+ int rc = -1, x;
+ struct visor_driver *drv = NULL;
+ void (*notify_func)(u32 bus_no, u32 dev_no, int response) = NULL;
+
+ if (is_pause)
+ notify_func = chipset_responders.device_pause;
+ else
+ notify_func = chipset_responders.device_resume;
+ if (!notify_func)
+ goto away;
+
+ if (!visorchipset_get_device_info(bus_no, dev_no, &dev_info))
+ goto away;
+
+ dev = find_visor_device_by_channel(dev_info.chan_info.channel_addr);
+ if (!dev)
+ goto away;
+
+ drv = to_visor_driver(dev->device.driver);
+ if (!drv)
+ goto away;
+
+ if (dev->pausing || dev->resuming)
+ goto away;
+
+ /* Note that even though both drv->pause() and drv->resume
+ * specify a callback function, it is NOT necessary for us to
+ * increment our local module usage count. Reason is, there
+ * is already a linkage dependency between child function
+ * drivers and visorbus, so it is already IMPOSSIBLE to unload
+ * visorbus while child function drivers are still running.
+ */
+ if (is_pause) {
+ if (!drv->pause)
+ goto away;
+
+ dev->pausing = TRUE;
+ x = drv->pause(dev, pause_state_change_complete);
+ } else {
+ /* This should be done at BUS resume time, but an
+ * existing problem prevents us from ever getting a bus
+ * resume... This hack would fail to work should we
+ * ever have a bus that contains NO devices, since we
+ * would never even get here in that case. */
+ fix_vbus_dev_info(dev);
+ if (!drv->resume)
+ goto away;
+
+ dev->resuming = TRUE;
+ x = drv->resume(dev, resume_state_change_complete);
+ }
+ if (x < 0) {
+ if (is_pause)
+ dev->pausing = FALSE;
+ else
+ dev->resuming = FALSE;
+ goto away;
+ }
+ rc = 0;
+away:
+ if (rc < 0) {
+ if (notify_func)
+ (*notify_func)(bus_no, dev_no, rc);
+ }
+}
+
+static void
+chipset_device_pause(u32 bus_no, u32 dev_no)
+{
+ initiate_chipset_device_pause_resume(bus_no, dev_no, TRUE);
+}
+
+static void
+chipset_device_resume(u32 bus_no, u32 dev_no)
+{
+ initiate_chipset_device_pause_resume(bus_no, dev_no, FALSE);
+}
+
+struct channel_size_info {
+ uuid_le guid;
+ unsigned long min_size;
+ unsigned long max_size;
+};
+
+static int __init
+visorbus_init(void)
+{
+ int rc = 0;
+
+ POSTCODE_LINUX_3(DRIVER_ENTRY_PC, rc, POSTCODE_SEVERITY_INFO);
+ bus_device_info_init(&clientbus_driverinfo,
+ "clientbus", MYDRVNAME,
+ VERSION, NULL);
+
+ /* process module options */
+
+ if (visorbus_devicetest > MAXDEVICETEST)
+ visorbus_devicetest = MAXDEVICETEST;
+
+ rc = create_bus_type();
+ if (rc < 0) {
+ POSTCODE_LINUX_2(BUS_CREATE_ENTRY_PC, DIAG_SEVERITY_ERR);
+ goto away;
+ }
+
+ periodic_dev_workqueue = create_singlethread_workqueue("visorbus_dev");
+ if (!periodic_dev_workqueue) {
+ POSTCODE_LINUX_2(CREATE_WORKQUEUE_PC, DIAG_SEVERITY_ERR);
+ rc = -ENOMEM;
+ goto away;
+ }
+
+ /* This enables us to receive notifications when devices appear for
+ * which this service partition is to be a server for.
+ */
+ visorchipset_register_busdev_server(&chipset_notifiers,
+ &chipset_responders,
+ &chipset_driverinfo);
+
+ rc = 0;
+
+away:
+ if (rc)
+ POSTCODE_LINUX_3(CHIPSET_INIT_FAILURE_PC, rc,
+ POSTCODE_SEVERITY_ERR);
+ return rc;
+}
+
+static void
+visorbus_exit(void)
+{
+ struct list_head *listentry, *listtmp;
+
+ visorchipset_register_busdev_server(NULL, NULL, NULL);
+ remove_all_visor_devices();
+
+ flush_workqueue(periodic_dev_workqueue); /* better not be any work! */
+ destroy_workqueue(periodic_dev_workqueue);
+ periodic_dev_workqueue = NULL;
+
+ if (periodic_test_workqueue) {
+ cancel_delayed_work(&periodic_work);
+ flush_workqueue(periodic_test_workqueue);
+ destroy_workqueue(periodic_test_workqueue);
+ periodic_test_workqueue = NULL;
+ }
+
+ list_for_each_safe(listentry, listtmp, &list_all_bus_instances) {
+ struct visorbus_devdata *devdata = list_entry(listentry,
+ struct
+ visorbus_devdata,
+ list_all);
+ remove_bus_instance(devdata);
+ }
+ remove_bus_type();
+}
+
+module_param_named(debug, visorbus_debug, int, S_IRUGO);
+MODULE_PARM_DESC(visorbus_debug, "1 to debug");
+int visorbus_debug = 0;
+
+module_param_named(forcematch, visorbus_forcematch, int, S_IRUGO);
+MODULE_PARM_DESC(visorbus_forcematch,
+ "1 to force a successful dev <--> drv match");
+int visorbus_forcematch = 0;
+
+module_param_named(forcenomatch, visorbus_forcenomatch, int, S_IRUGO);
+MODULE_PARM_DESC(visorbus_forcenomatch,
+ "1 to force an UNsuccessful dev <--> drv match");
+int visorbus_forcenomatch = 0;
+
+module_param_named(devicetest, visorbus_devicetest, int, S_IRUGO);
+MODULE_PARM_DESC(visorbus_devicetest,
+ "non-0 to just test device creation and destruction");
+int visorbus_devicetest = 0;
+
+module_param_named(debugref, visorbus_debugref, int, S_IRUGO);
+MODULE_PARM_DESC(visorbus_debugref, "1 to debug reference counting");
+int visorbus_debugref = 0;
+
+module_param_named(serialloopbacktest, visorbus_serialloopbacktest,
+ int, S_IRUGO);
+MODULE_PARM_DESC(visorbus_serialloopbacktest,
+ "non-0 to just create 2 serial devices on the same channel");
+int visorbus_serialloopbacktest = 0;
+
+module_init(visorbus_init);
+module_exit(visorbus_exit);
+
+MODULE_AUTHOR("Unisys");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Supervisor bus driver for service partition: ver " VERSION);
+MODULE_VERSION(VERSION);