/*
- * drivers/s390/cio/css.c
- * driver for channel subsystem
+ * driver for channel subsystem
*
- * Copyright IBM Corp. 2002,2008
- * Author(s): Arnd Bergmann (arndb@de.ibm.com)
- * Cornelia Huck (cornelia.huck@de.ibm.com)
+ * Copyright IBM Corp. 2002, 2009
+ *
+ * Author(s): Arnd Bergmann (arndb@de.ibm.com)
+ * Cornelia Huck (cornelia.huck@de.ibm.com)
*/
+
+#define KMSG_COMPONENT "cio"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/reboot.h>
+#include <linux/suspend.h>
#include <asm/isc.h>
+#include <asm/crw.h>
-#include "../s390mach.h"
#include "css.h"
#include "cio.h"
#include "cio_debug.h"
#include "chp.h"
int css_init_done = 0;
-static int need_reprobe = 0;
-static int max_ssid = 0;
+int max_ssid;
struct channel_subsystem *channel_subsystems[__MAX_CSSID + 1];
return rc;
}
+static int call_fn_all_sch(struct subchannel_id schid, void *data)
+{
+ struct cb_data *cb = data;
+ struct subchannel *sch;
+ int rc = 0;
+
+ sch = get_subchannel_by_schid(schid);
+ if (sch) {
+ if (cb->fn_known_sch)
+ rc = cb->fn_known_sch(sch, cb->data);
+ put_device(&sch->dev);
+ } else {
+ if (cb->fn_unknown_sch)
+ rc = cb->fn_unknown_sch(schid, cb->data);
+ }
+
+ return rc;
+}
+
int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
int (*fn_unknown)(struct subchannel_id,
void *), void *data)
struct cb_data cb;
int rc;
- cb.set = idset_sch_new();
- if (!cb.set)
- return -ENOMEM;
- idset_fill(cb.set);
cb.data = data;
cb.fn_known_sch = fn_known;
cb.fn_unknown_sch = fn_unknown;
+
+ cb.set = idset_sch_new();
+ if (!cb.set)
+ /* fall back to brute force scanning in case of oom */
+ return for_each_subchannel(call_fn_all_sch, &cb);
+
+ idset_fill(cb.set);
+
/* Process registered subchannels. */
rc = bus_for_each_dev(&css_bus_type, NULL, &cb, call_fn_known_sch);
if (rc)
}
static void
-css_free_subchannel(struct subchannel *sch)
-{
- if (sch) {
- /* Reset intparm to zeroes. */
- sch->schib.pmcw.intparm = 0;
- cio_modify(sch);
- kfree(sch->lock);
- kfree(sch);
- }
-}
-
-static void
css_subchannel_release(struct device *dev)
{
struct subchannel *sch;
sch = to_subchannel(dev);
if (!cio_is_console(sch->schid)) {
+ /* Reset intparm to zeroes. */
+ sch->config.intparm = 0;
+ cio_commit_config(sch);
kfree(sch->lock);
kfree(sch);
}
int ret;
mutex_lock(&sch->reg_mutex);
+ dev_set_name(&sch->dev, "0.%x.%04x", sch->schid.ssid,
+ sch->schid.sch_no);
ret = device_register(&sch->dev);
mutex_unlock(&sch->reg_mutex);
return ret;
void css_sch_device_unregister(struct subchannel *sch)
{
mutex_lock(&sch->reg_mutex);
- device_unregister(&sch->dev);
+ if (device_is_registered(&sch->dev))
+ device_unregister(&sch->dev);
mutex_unlock(&sch->reg_mutex);
}
EXPORT_SYMBOL_GPL(css_sch_device_unregister);
.attrs = subch_attrs,
};
-static struct attribute_group *default_subch_attr_groups[] = {
+static const struct attribute_group *default_subch_attr_groups[] = {
&subch_attr_group,
NULL,
};
* the subchannel driver can decide itself when it wants to inform
* userspace of its existence.
*/
- sch->dev.uevent_suppress = 1;
+ dev_set_uevent_suppress(&sch->dev, 1);
css_update_ssd_info(sch);
/* make it known to the system */
ret = css_sch_device_register(sch);
* a fitting driver module may be loaded based on the
* modalias.
*/
- sch->dev.uevent_suppress = 0;
+ dev_set_uevent_suppress(&sch->dev, 0);
kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
}
return ret;
int ret;
struct subchannel *sch;
- sch = css_alloc_subchannel(schid);
- if (IS_ERR(sch))
- return PTR_ERR(sch);
+ if (cio_is_console(schid))
+ sch = cio_get_console_subchannel();
+ else {
+ sch = css_alloc_subchannel(schid);
+ if (IS_ERR(sch))
+ return PTR_ERR(sch);
+ }
ret = css_register_subchannel(sch);
- if (ret)
- css_free_subchannel(sch);
+ if (ret) {
+ if (!cio_is_console(schid))
+ put_device(&sch->dev);
+ }
return ret;
}
static struct idset *slow_subchannel_set;
static spinlock_t slow_subchannel_lock;
+static wait_queue_head_t css_eval_wq;
+static atomic_t css_eval_scheduled;
static int __init slow_subchannel_init(void)
{
spin_lock_init(&slow_subchannel_lock);
+ atomic_set(&css_eval_scheduled, 0);
+ init_waitqueue_head(&css_eval_wq);
slow_subchannel_set = idset_sch_new();
if (!slow_subchannel_set) {
CIO_MSG_EVENT(0, "could not allocate slow subchannel set\n");
static void css_slow_path_func(struct work_struct *unused)
{
+ unsigned long flags;
+
CIO_TRACE_EVENT(4, "slowpath");
for_each_subchannel_staged(slow_eval_known_fn, slow_eval_unknown_fn,
NULL);
+ spin_lock_irqsave(&slow_subchannel_lock, flags);
+ if (idset_is_empty(slow_subchannel_set)) {
+ atomic_set(&css_eval_scheduled, 0);
+ wake_up(&css_eval_wq);
+ }
+ spin_unlock_irqrestore(&slow_subchannel_lock, flags);
}
static DECLARE_WORK(slow_path_work, css_slow_path_func);
spin_lock_irqsave(&slow_subchannel_lock, flags);
idset_sch_add(slow_subchannel_set, schid);
+ atomic_set(&css_eval_scheduled, 1);
queue_work(slow_path_wq, &slow_path_work);
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
}
spin_lock_irqsave(&slow_subchannel_lock, flags);
idset_fill(slow_subchannel_set);
+ atomic_set(&css_eval_scheduled, 1);
queue_work(slow_path_wq, &slow_path_work);
spin_unlock_irqrestore(&slow_subchannel_lock, flags);
}
-void css_wait_for_slow_path(void)
+static int __unset_registered(struct device *dev, void *data)
{
- flush_workqueue(ccw_device_notify_work);
- flush_workqueue(slow_path_wq);
+ struct idset *set = data;
+ struct subchannel *sch = to_subchannel(dev);
+
+ idset_sch_del(set, sch->schid);
+ return 0;
}
-/* Reprobe subchannel if unregistered. */
-static int reprobe_subchannel(struct subchannel_id schid, void *data)
+void css_schedule_eval_all_unreg(void)
{
- int ret;
-
- CIO_MSG_EVENT(6, "cio: reprobe 0.%x.%04x\n",
- schid.ssid, schid.sch_no);
- if (need_reprobe)
- return -EAGAIN;
+ unsigned long flags;
+ struct idset *unreg_set;
- ret = css_probe_device(schid);
- switch (ret) {
- case 0:
- break;
- case -ENXIO:
- case -ENOMEM:
- case -EIO:
- /* These should abort looping */
- break;
- default:
- ret = 0;
+ /* Find unregistered subchannels. */
+ unreg_set = idset_sch_new();
+ if (!unreg_set) {
+ /* Fallback. */
+ css_schedule_eval_all();
+ return;
}
-
- return ret;
+ idset_fill(unreg_set);
+ bus_for_each_dev(&css_bus_type, NULL, unreg_set, __unset_registered);
+ /* Apply to slow_subchannel_set. */
+ spin_lock_irqsave(&slow_subchannel_lock, flags);
+ idset_add_set(slow_subchannel_set, unreg_set);
+ atomic_set(&css_eval_scheduled, 1);
+ queue_work(slow_path_wq, &slow_path_work);
+ spin_unlock_irqrestore(&slow_subchannel_lock, flags);
+ idset_free(unreg_set);
}
-/* Work function used to reprobe all unregistered subchannels. */
-static void reprobe_all(struct work_struct *unused)
+void css_wait_for_slow_path(void)
{
- int ret;
-
- CIO_MSG_EVENT(4, "reprobe start\n");
-
- need_reprobe = 0;
- /* Make sure initial subchannel scan is done. */
- wait_event(ccw_device_init_wq,
- atomic_read(&ccw_device_init_count) == 0);
- ret = for_each_subchannel_staged(NULL, reprobe_subchannel, NULL);
-
- CIO_MSG_EVENT(4, "reprobe done (rc=%d, need_reprobe=%d)\n", ret,
- need_reprobe);
+ flush_workqueue(slow_path_wq);
}
-static DECLARE_WORK(css_reprobe_work, reprobe_all);
-
/* Schedule reprobing of all unregistered subchannels. */
void css_schedule_reprobe(void)
{
- need_reprobe = 1;
- queue_work(slow_path_wq, &css_reprobe_work);
+ css_schedule_eval_all_unreg();
}
-
EXPORT_SYMBOL_GPL(css_schedule_reprobe);
/*
css_evaluate_subchannel(mchk_schid, 0);
}
-static int __init
-__init_channel_subsystem(struct subchannel_id schid, void *data)
-{
- struct subchannel *sch;
- int ret;
-
- if (cio_is_console(schid))
- sch = cio_get_console_subchannel();
- else {
- sch = css_alloc_subchannel(schid);
- if (IS_ERR(sch))
- ret = PTR_ERR(sch);
- else
- ret = 0;
- switch (ret) {
- case 0:
- break;
- case -ENOMEM:
- panic("Out of memory in init_channel_subsystem\n");
- /* -ENXIO: no more subchannels. */
- case -ENXIO:
- return ret;
- /* -EIO: this subchannel set not supported. */
- case -EIO:
- return ret;
- default:
- return 0;
- }
- }
- /*
- * We register ALL valid subchannels in ioinfo, even those
- * that have been present before init_channel_subsystem.
- * These subchannels can't have been registered yet (kmalloc
- * not working) so we do it now. This is true e.g. for the
- * console subchannel.
- */
- css_register_subchannel(sch);
- return 0;
-}
-
static void __init
css_generate_pgid(struct channel_subsystem *css, u32 tod_high)
{
css->global_pgid.pgid_high.ext_cssid.cssid = css->cssid;
} else {
#ifdef CONFIG_SMP
- css->global_pgid.pgid_high.cpu_addr = hard_smp_processor_id();
+ css->global_pgid.pgid_high.cpu_addr = stap();
#else
css->global_pgid.pgid_high.cpu_addr = 0;
#endif
}
- css->global_pgid.cpu_id = ((cpuid_t *) __LC_CPUID)->ident;
- css->global_pgid.cpu_model = ((cpuid_t *) __LC_CPUID)->machine;
+ css->global_pgid.cpu_id = S390_lowcore.cpu_id.ident;
+ css->global_pgid.cpu_model = S390_lowcore.cpu_id.machine;
css->global_pgid.tod_high = tod_high;
}
css = to_css(dev);
mutex_destroy(&css->mutex);
+ if (css->pseudo_subchannel) {
+ /* Implies that it has been generated but never registered. */
+ css_subchannel_release(&css->pseudo_subchannel->dev);
+ css->pseudo_subchannel = NULL;
+ }
kfree(css);
}
return -ENOMEM;
css->pseudo_subchannel->dev.parent = &css->device;
css->pseudo_subchannel->dev.release = css_subchannel_release;
- sprintf(css->pseudo_subchannel->dev.bus_id, "defunct");
+ dev_set_name(&css->pseudo_subchannel->dev, "defunct");
ret = cio_create_sch_lock(css->pseudo_subchannel);
if (ret) {
kfree(css->pseudo_subchannel);
mutex_init(&css->mutex);
css->valid = 1;
css->cssid = nr;
- sprintf(css->device.bus_id, "css%x", nr);
+ dev_set_name(&css->device, "css%x", nr);
css->device.release = channel_subsystem_release;
tod_high = (u32) (get_clock() >> 32);
css_generate_pgid(css, tod_high);
};
/*
+ * Since the css devices are neither on a bus nor have a class
+ * nor have a special device type, we cannot stop/restart channel
+ * path measurements via the normal suspend/resume callbacks, but have
+ * to use notifiers.
+ */
+static int css_power_event(struct notifier_block *this, unsigned long event,
+ void *ptr)
+{
+ void *secm_area;
+ int ret, i;
+
+ switch (event) {
+ case PM_HIBERNATION_PREPARE:
+ case PM_SUSPEND_PREPARE:
+ ret = NOTIFY_DONE;
+ for (i = 0; i <= __MAX_CSSID; i++) {
+ struct channel_subsystem *css;
+
+ css = channel_subsystems[i];
+ mutex_lock(&css->mutex);
+ if (!css->cm_enabled) {
+ mutex_unlock(&css->mutex);
+ continue;
+ }
+ secm_area = (void *)get_zeroed_page(GFP_KERNEL |
+ GFP_DMA);
+ if (secm_area) {
+ if (__chsc_do_secm(css, 0, secm_area))
+ ret = NOTIFY_BAD;
+ free_page((unsigned long)secm_area);
+ } else
+ ret = NOTIFY_BAD;
+
+ mutex_unlock(&css->mutex);
+ }
+ break;
+ case PM_POST_HIBERNATION:
+ case PM_POST_SUSPEND:
+ ret = NOTIFY_DONE;
+ for (i = 0; i <= __MAX_CSSID; i++) {
+ struct channel_subsystem *css;
+
+ css = channel_subsystems[i];
+ mutex_lock(&css->mutex);
+ if (!css->cm_enabled) {
+ mutex_unlock(&css->mutex);
+ continue;
+ }
+ secm_area = (void *)get_zeroed_page(GFP_KERNEL |
+ GFP_DMA);
+ if (secm_area) {
+ if (__chsc_do_secm(css, 1, secm_area))
+ ret = NOTIFY_BAD;
+ free_page((unsigned long)secm_area);
+ } else
+ ret = NOTIFY_BAD;
+
+ mutex_unlock(&css->mutex);
+ }
+ /* search for subchannels, which appeared during hibernation */
+ css_schedule_reprobe();
+ break;
+ default:
+ ret = NOTIFY_DONE;
+ }
+ return ret;
+
+}
+static struct notifier_block css_power_notifier = {
+ .notifier_call = css_power_event,
+};
+
+/*
* Now that the driver core is running, we can setup our channel subsystem.
* The struct subchannel's are created during probing (except for the
* static console subchannel).
*/
-static int __init
-init_channel_subsystem (void)
+static int __init css_bus_init(void)
{
int ret, i;
ret = chsc_determine_css_characteristics();
if (ret == -ENOMEM)
- goto out; /* No need to continue. */
-
- ret = chsc_alloc_sei_area();
- if (ret)
goto out;
- ret = slow_subchannel_init();
- if (ret)
- goto out;
-
- ret = s390_register_crw_handler(CRW_RSC_SCH, css_process_crw);
+ ret = chsc_alloc_sei_area();
if (ret)
goto out;
- if ((ret = bus_register(&css_bus_type)))
- goto out;
-
/* Try to enable MSS. */
ret = chsc_enable_facility(CHSC_SDA_OC_MSS);
switch (ret) {
max_ssid = __MAX_SSID;
break;
case -ENOMEM:
- goto out_bus;
+ goto out;
default:
max_ssid = 0;
}
+
+ ret = slow_subchannel_init();
+ if (ret)
+ goto out;
+
+ ret = crw_register_handler(CRW_RSC_SCH, css_process_crw);
+ if (ret)
+ goto out;
+
+ if ((ret = bus_register(&css_bus_type)))
+ goto out;
+
/* Setup css structure. */
for (i = 0; i <= __MAX_CSSID; i++) {
struct channel_subsystem *css;
}
channel_subsystems[i] = css;
ret = setup_css(i);
- if (ret)
- goto out_free;
+ if (ret) {
+ kfree(channel_subsystems[i]);
+ goto out_unregister;
+ }
ret = device_register(&css->device);
- if (ret)
- goto out_free_all;
+ if (ret) {
+ put_device(&css->device);
+ goto out_unregister;
+ }
if (css_chsc_characteristics.secm) {
ret = device_create_file(&css->device,
&dev_attr_cm_enable);
goto out_device;
}
ret = device_register(&css->pseudo_subchannel->dev);
- if (ret)
+ if (ret) {
+ put_device(&css->pseudo_subchannel->dev);
goto out_file;
+ }
}
ret = register_reboot_notifier(&css_reboot_notifier);
if (ret)
- goto out_pseudo;
+ goto out_unregister;
+ ret = register_pm_notifier(&css_power_notifier);
+ if (ret) {
+ unregister_reboot_notifier(&css_reboot_notifier);
+ goto out_unregister;
+ }
css_init_done = 1;
/* Enable default isc for I/O subchannels. */
isc_register(IO_SCH_ISC);
- for_each_subchannel(__init_channel_subsystem, NULL);
return 0;
-out_pseudo:
- device_unregister(&channel_subsystems[i]->pseudo_subchannel->dev);
out_file:
- device_remove_file(&channel_subsystems[i]->device,
- &dev_attr_cm_enable);
+ if (css_chsc_characteristics.secm)
+ device_remove_file(&channel_subsystems[i]->device,
+ &dev_attr_cm_enable);
out_device:
device_unregister(&channel_subsystems[i]->device);
-out_free_all:
- kfree(channel_subsystems[i]->pseudo_subchannel->lock);
- kfree(channel_subsystems[i]->pseudo_subchannel);
-out_free:
- kfree(channel_subsystems[i]);
out_unregister:
while (i > 0) {
struct channel_subsystem *css;
i--;
css = channel_subsystems[i];
device_unregister(&css->pseudo_subchannel->dev);
+ css->pseudo_subchannel = NULL;
if (css_chsc_characteristics.secm)
device_remove_file(&css->device,
&dev_attr_cm_enable);
device_unregister(&css->device);
}
-out_bus:
bus_unregister(&css_bus_type);
out:
- s390_unregister_crw_handler(CRW_RSC_CSS);
+ crw_unregister_handler(CRW_RSC_CSS);
chsc_free_sei_area();
- kfree(slow_subchannel_set);
- printk(KERN_WARNING"cio: failed to initialize css driver (%d)!\n",
- ret);
+ idset_free(slow_subchannel_set);
+ pr_alert("The CSS device driver initialization failed with "
+ "errno=%d\n", ret);
return ret;
}
-int sch_is_pseudo_sch(struct subchannel *sch)
+static void __init css_bus_cleanup(void)
{
- return sch == to_css(sch->dev.parent)->pseudo_subchannel;
+ struct channel_subsystem *css;
+ int i;
+
+ for (i = 0; i <= __MAX_CSSID; i++) {
+ css = channel_subsystems[i];
+ device_unregister(&css->pseudo_subchannel->dev);
+ css->pseudo_subchannel = NULL;
+ if (css_chsc_characteristics.secm)
+ device_remove_file(&css->device, &dev_attr_cm_enable);
+ device_unregister(&css->device);
+ }
+ bus_unregister(&css_bus_type);
+ crw_unregister_handler(CRW_RSC_CSS);
+ chsc_free_sei_area();
+ idset_free(slow_subchannel_set);
+ isc_unregister(IO_SCH_ISC);
+}
+
+static int __init channel_subsystem_init(void)
+{
+ int ret;
+
+ ret = css_bus_init();
+ if (ret)
+ return ret;
+
+ ret = io_subchannel_init();
+ if (ret)
+ css_bus_cleanup();
+
+ return ret;
+}
+subsys_initcall(channel_subsystem_init);
+
+static int css_settle(struct device_driver *drv, void *unused)
+{
+ struct css_driver *cssdrv = to_cssdriver(drv);
+
+ if (cssdrv->settle)
+ cssdrv->settle();
+ return 0;
}
/*
- * find a driver for a subchannel. They identify by the subchannel
- * type with the exception that the console subchannel driver has its own
- * subchannel type although the device is an i/o subchannel
+ * Wait for the initialization of devices to finish, to make sure we are
+ * done with our setup if the search for the root device starts.
*/
-static int
-css_bus_match (struct device *dev, struct device_driver *drv)
+static int __init channel_subsystem_init_sync(void)
+{
+ /* Start initial subchannel evaluation. */
+ css_schedule_eval_all();
+ /* Wait for the evaluation of subchannels to finish. */
+ wait_event(css_eval_wq, atomic_read(&css_eval_scheduled) == 0);
+ /* Wait for the subchannel type specific initialization to finish */
+ return bus_for_each_drv(&css_bus_type, NULL, NULL, css_settle);
+}
+subsys_initcall_sync(channel_subsystem_init_sync);
+
+int sch_is_pseudo_sch(struct subchannel *sch)
+{
+ return sch == to_css(sch->dev.parent)->pseudo_subchannel;
+}
+
+static int css_bus_match(struct device *dev, struct device_driver *drv)
{
struct subchannel *sch = to_subchannel(dev);
struct css_driver *driver = to_cssdriver(drv);
+ struct css_device_id *id;
- if (sch->st == driver->subchannel_type)
- return 1;
+ for (id = driver->subchannel_type; id->match_flags; id++) {
+ if (sch->st == id->type)
+ return 1;
+ }
return 0;
}
return ret;
}
+static int css_pm_prepare(struct device *dev)
+{
+ struct subchannel *sch = to_subchannel(dev);
+ struct css_driver *drv;
+
+ if (mutex_is_locked(&sch->reg_mutex))
+ return -EAGAIN;
+ if (!sch->dev.driver)
+ return 0;
+ drv = to_cssdriver(sch->dev.driver);
+ /* Notify drivers that they may not register children. */
+ return drv->prepare ? drv->prepare(sch) : 0;
+}
+
+static void css_pm_complete(struct device *dev)
+{
+ struct subchannel *sch = to_subchannel(dev);
+ struct css_driver *drv;
+
+ if (!sch->dev.driver)
+ return;
+ drv = to_cssdriver(sch->dev.driver);
+ if (drv->complete)
+ drv->complete(sch);
+}
+
+static int css_pm_freeze(struct device *dev)
+{
+ struct subchannel *sch = to_subchannel(dev);
+ struct css_driver *drv;
+
+ if (!sch->dev.driver)
+ return 0;
+ drv = to_cssdriver(sch->dev.driver);
+ return drv->freeze ? drv->freeze(sch) : 0;
+}
+
+static int css_pm_thaw(struct device *dev)
+{
+ struct subchannel *sch = to_subchannel(dev);
+ struct css_driver *drv;
+
+ if (!sch->dev.driver)
+ return 0;
+ drv = to_cssdriver(sch->dev.driver);
+ return drv->thaw ? drv->thaw(sch) : 0;
+}
+
+static int css_pm_restore(struct device *dev)
+{
+ struct subchannel *sch = to_subchannel(dev);
+ struct css_driver *drv;
+
+ if (!sch->dev.driver)
+ return 0;
+ drv = to_cssdriver(sch->dev.driver);
+ return drv->restore ? drv->restore(sch) : 0;
+}
+
+static struct dev_pm_ops css_pm_ops = {
+ .prepare = css_pm_prepare,
+ .complete = css_pm_complete,
+ .freeze = css_pm_freeze,
+ .thaw = css_pm_thaw,
+ .restore = css_pm_restore,
+};
+
struct bus_type css_bus_type = {
.name = "css",
.match = css_bus_match,
.remove = css_remove,
.shutdown = css_shutdown,
.uevent = css_uevent,
+ .pm = &css_pm_ops,
};
/**
}
EXPORT_SYMBOL_GPL(css_driver_unregister);
-subsys_initcall(init_channel_subsystem);
-
MODULE_LICENSE("GPL");
EXPORT_SYMBOL(css_bus_type);