Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
new file mode 100644
index 0000000..87bd70e
--- /dev/null
+++ b/drivers/s390/cio/css.c
@@ -0,0 +1,575 @@
+/*
+ * drivers/s390/cio/css.c
+ * driver for channel subsystem
+ * $Revision: 1.85 $
+ *
+ * Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
+ * IBM Corporation
+ * Author(s): Arnd Bergmann (arndb@de.ibm.com)
+ * Cornelia Huck (cohuck@de.ibm.com)
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+
+#include "css.h"
+#include "cio.h"
+#include "cio_debug.h"
+#include "ioasm.h"
+#include "chsc.h"
+
+unsigned int highest_subchannel;
+int need_rescan = 0;
+int css_init_done = 0;
+
+struct pgid global_pgid;
+int css_characteristics_avail = 0;
+
+struct device css_bus_device = {
+ .bus_id = "css0",
+};
+
+static struct subchannel *
+css_alloc_subchannel(int irq)
+{
+ struct subchannel *sch;
+ int ret;
+
+ sch = kmalloc (sizeof (*sch), GFP_KERNEL | GFP_DMA);
+ if (sch == NULL)
+ return ERR_PTR(-ENOMEM);
+ ret = cio_validate_subchannel (sch, irq);
+ if (ret < 0) {
+ kfree(sch);
+ return ERR_PTR(ret);
+ }
+ if (irq > highest_subchannel)
+ highest_subchannel = irq;
+
+ if (sch->st != SUBCHANNEL_TYPE_IO) {
+ /* For now we ignore all non-io subchannels. */
+ kfree(sch);
+ return ERR_PTR(-EINVAL);
+ }
+
+ /*
+ * Set intparm to subchannel address.
+ * This is fine even on 64bit since the subchannel is always located
+ * under 2G.
+ */
+ sch->schib.pmcw.intparm = (__u32)(unsigned long)sch;
+ ret = cio_modify(sch);
+ if (ret) {
+ kfree(sch);
+ return ERR_PTR(ret);
+ }
+ return sch;
+}
+
+static void
+css_free_subchannel(struct subchannel *sch)
+{
+ if (sch) {
+ /* Reset intparm to zeroes. */
+ sch->schib.pmcw.intparm = 0;
+ cio_modify(sch);
+ kfree(sch);
+ }
+
+}
+
+static void
+css_subchannel_release(struct device *dev)
+{
+ struct subchannel *sch;
+
+ sch = to_subchannel(dev);
+ if (!cio_is_console(sch->irq))
+ kfree(sch);
+}
+
+extern int css_get_ssd_info(struct subchannel *sch);
+
+static int
+css_register_subchannel(struct subchannel *sch)
+{
+ int ret;
+
+ /* Initialize the subchannel structure */
+ sch->dev.parent = &css_bus_device;
+ sch->dev.bus = &css_bus_type;
+ sch->dev.release = &css_subchannel_release;
+
+ /* make it known to the system */
+ ret = device_register(&sch->dev);
+ if (ret)
+ printk (KERN_WARNING "%s: could not register %s\n",
+ __func__, sch->dev.bus_id);
+ else
+ css_get_ssd_info(sch);
+ return ret;
+}
+
+int
+css_probe_device(int irq)
+{
+ int ret;
+ struct subchannel *sch;
+
+ sch = css_alloc_subchannel(irq);
+ if (IS_ERR(sch))
+ return PTR_ERR(sch);
+ ret = css_register_subchannel(sch);
+ if (ret)
+ css_free_subchannel(sch);
+ return ret;
+}
+
+struct subchannel *
+get_subchannel_by_schid(int irq)
+{
+ struct subchannel *sch;
+ struct list_head *entry;
+ struct device *dev;
+
+ if (!get_bus(&css_bus_type))
+ return NULL;
+ down_read(&css_bus_type.subsys.rwsem);
+ sch = NULL;
+ list_for_each(entry, &css_bus_type.devices.list) {
+ dev = get_device(container_of(entry,
+ struct device, bus_list));
+ if (!dev)
+ continue;
+ sch = to_subchannel(dev);
+ if (sch->irq == irq)
+ break;
+ put_device(dev);
+ sch = NULL;
+ }
+ up_read(&css_bus_type.subsys.rwsem);
+ put_bus(&css_bus_type);
+
+ return sch;
+}
+
+static inline int
+css_get_subchannel_status(struct subchannel *sch, int schid)
+{
+ struct schib schib;
+ int cc;
+
+ cc = stsch(schid, &schib);
+ if (cc)
+ return CIO_GONE;
+ if (!schib.pmcw.dnv)
+ return CIO_GONE;
+ if (sch && sch->schib.pmcw.dnv &&
+ (schib.pmcw.dev != sch->schib.pmcw.dev))
+ return CIO_REVALIDATE;
+ if (sch && !sch->lpm)
+ return CIO_NO_PATH;
+ return CIO_OPER;
+}
+
+static int
+css_evaluate_subchannel(int irq, int slow)
+{
+ int event, ret, disc;
+ struct subchannel *sch;
+ unsigned long flags;
+
+ sch = get_subchannel_by_schid(irq);
+ disc = sch ? device_is_disconnected(sch) : 0;
+ if (disc && slow) {
+ if (sch)
+ put_device(&sch->dev);
+ return 0; /* Already processed. */
+ }
+ /*
+ * We've got a machine check, so running I/O won't get an interrupt.
+ * Kill any pending timers.
+ */
+ if (sch)
+ device_kill_pending_timer(sch);
+ if (!disc && !slow) {
+ if (sch)
+ put_device(&sch->dev);
+ return -EAGAIN; /* Will be done on the slow path. */
+ }
+ event = css_get_subchannel_status(sch, irq);
+ CIO_MSG_EVENT(4, "Evaluating schid %04x, event %d, %s, %s path.\n",
+ irq, event, sch?(disc?"disconnected":"normal"):"unknown",
+ slow?"slow":"fast");
+ switch (event) {
+ case CIO_NO_PATH:
+ case CIO_GONE:
+ if (!sch) {
+ /* Never used this subchannel. Ignore. */
+ ret = 0;
+ break;
+ }
+ if (disc && (event == CIO_NO_PATH)) {
+ /*
+ * Uargh, hack again. Because we don't get a machine
+ * check on configure on, our path bookkeeping can
+ * be out of date here (it's fine while we only do
+ * logical varying or get chsc machine checks). We
+ * need to force reprobing or we might miss devices
+ * coming operational again. It won't do harm in real
+ * no path situations.
+ */
+ spin_lock_irqsave(&sch->lock, flags);
+ device_trigger_reprobe(sch);
+ spin_unlock_irqrestore(&sch->lock, flags);
+ ret = 0;
+ break;
+ }
+ if (sch->driver && sch->driver->notify &&
+ sch->driver->notify(&sch->dev, event)) {
+ cio_disable_subchannel(sch);
+ device_set_disconnected(sch);
+ ret = 0;
+ break;
+ }
+ /*
+ * Unregister subchannel.
+ * The device will be killed automatically.
+ */
+ cio_disable_subchannel(sch);
+ device_unregister(&sch->dev);
+ /* Reset intparm to zeroes. */
+ sch->schib.pmcw.intparm = 0;
+ cio_modify(sch);
+ put_device(&sch->dev);
+ ret = 0;
+ break;
+ case CIO_REVALIDATE:
+ /*
+ * Revalidation machine check. Sick.
+ * We don't notify the driver since we have to throw the device
+ * away in any case.
+ */
+ if (!disc) {
+ device_unregister(&sch->dev);
+ /* Reset intparm to zeroes. */
+ sch->schib.pmcw.intparm = 0;
+ cio_modify(sch);
+ put_device(&sch->dev);
+ ret = css_probe_device(irq);
+ } else {
+ /*
+ * We can't immediately deregister the disconnected
+ * device since it might block.
+ */
+ spin_lock_irqsave(&sch->lock, flags);
+ device_trigger_reprobe(sch);
+ spin_unlock_irqrestore(&sch->lock, flags);
+ ret = 0;
+ }
+ break;
+ case CIO_OPER:
+ if (disc) {
+ spin_lock_irqsave(&sch->lock, flags);
+ /* Get device operational again. */
+ device_trigger_reprobe(sch);
+ spin_unlock_irqrestore(&sch->lock, flags);
+ }
+ ret = sch ? 0 : css_probe_device(irq);
+ break;
+ default:
+ BUG();
+ ret = 0;
+ }
+ return ret;
+}
+
+static void
+css_rescan_devices(void)
+{
+ int irq, ret;
+
+ for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
+ ret = css_evaluate_subchannel(irq, 1);
+ /* No more memory. It doesn't make sense to continue. No
+ * panic because this can happen in midflight and just
+ * because we can't use a new device is no reason to crash
+ * the system. */
+ if (ret == -ENOMEM)
+ break;
+ /* -ENXIO indicates that there are no more subchannels. */
+ if (ret == -ENXIO)
+ break;
+ }
+}
+
+struct slow_subchannel {
+ struct list_head slow_list;
+ unsigned long schid;
+};
+
+static LIST_HEAD(slow_subchannels_head);
+static DEFINE_SPINLOCK(slow_subchannel_lock);
+
+static void
+css_trigger_slow_path(void)
+{
+ CIO_TRACE_EVENT(4, "slowpath");
+
+ if (need_rescan) {
+ need_rescan = 0;
+ css_rescan_devices();
+ return;
+ }
+
+ spin_lock_irq(&slow_subchannel_lock);
+ while (!list_empty(&slow_subchannels_head)) {
+ struct slow_subchannel *slow_sch =
+ list_entry(slow_subchannels_head.next,
+ struct slow_subchannel, slow_list);
+
+ list_del_init(slow_subchannels_head.next);
+ spin_unlock_irq(&slow_subchannel_lock);
+ css_evaluate_subchannel(slow_sch->schid, 1);
+ spin_lock_irq(&slow_subchannel_lock);
+ kfree(slow_sch);
+ }
+ spin_unlock_irq(&slow_subchannel_lock);
+}
+
+typedef void (*workfunc)(void *);
+DECLARE_WORK(slow_path_work, (workfunc)css_trigger_slow_path, NULL);
+struct workqueue_struct *slow_path_wq;
+
+/*
+ * Rescan for new devices. FIXME: This is slow.
+ * This function is called when we have lost CRWs due to overflows and we have
+ * to do subchannel housekeeping.
+ */
+void
+css_reiterate_subchannels(void)
+{
+ css_clear_subchannel_slow_list();
+ need_rescan = 1;
+}
+
+/*
+ * Called from the machine check handler for subchannel report words.
+ */
+int
+css_process_crw(int irq)
+{
+ int ret;
+
+ CIO_CRW_EVENT(2, "source is subchannel %04X\n", irq);
+
+ if (need_rescan)
+ /* We need to iterate all subchannels anyway. */
+ return -EAGAIN;
+ /*
+ * Since we are always presented with IPI in the CRW, we have to
+ * use stsch() to find out if the subchannel in question has come
+ * or gone.
+ */
+ ret = css_evaluate_subchannel(irq, 0);
+ if (ret == -EAGAIN) {
+ if (css_enqueue_subchannel_slow(irq)) {
+ css_clear_subchannel_slow_list();
+ need_rescan = 1;
+ }
+ }
+ return ret;
+}
+
+static void __init
+css_generate_pgid(void)
+{
+ /* Let's build our path group ID here. */
+ if (css_characteristics_avail && css_general_characteristics.mcss)
+ global_pgid.cpu_addr = 0x8000;
+ else {
+#ifdef CONFIG_SMP
+ global_pgid.cpu_addr = hard_smp_processor_id();
+#else
+ global_pgid.cpu_addr = 0;
+#endif
+ }
+ global_pgid.cpu_id = ((cpuid_t *) __LC_CPUID)->ident;
+ global_pgid.cpu_model = ((cpuid_t *) __LC_CPUID)->machine;
+ global_pgid.tod_high = (__u32) (get_clock() >> 32);
+}
+
+/*
+ * 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)
+{
+ int ret, irq;
+
+ if (chsc_determine_css_characteristics() == 0)
+ css_characteristics_avail = 1;
+
+ css_generate_pgid();
+
+ if ((ret = bus_register(&css_bus_type)))
+ goto out;
+ if ((ret = device_register (&css_bus_device)))
+ goto out_bus;
+
+ css_init_done = 1;
+
+ ctl_set_bit(6, 28);
+
+ for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
+ struct subchannel *sch;
+
+ if (cio_is_console(irq))
+ sch = cio_get_console_subchannel();
+ else {
+ sch = css_alloc_subchannel(irq);
+ if (IS_ERR(sch))
+ ret = PTR_ERR(sch);
+ else
+ ret = 0;
+ if (ret == -ENOMEM)
+ panic("Out of memory in "
+ "init_channel_subsystem\n");
+ /* -ENXIO: no more subchannels. */
+ if (ret == -ENXIO)
+ break;
+ if (ret)
+ continue;
+ }
+ /*
+ * 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;
+
+out_bus:
+ bus_unregister(&css_bus_type);
+out:
+ return ret;
+}
+
+/*
+ * 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
+ */
+static int
+css_bus_match (struct device *dev, struct device_driver *drv)
+{
+ struct subchannel *sch = container_of (dev, struct subchannel, dev);
+ struct css_driver *driver = container_of (drv, struct css_driver, drv);
+
+ if (sch->st == driver->subchannel_type)
+ return 1;
+
+ return 0;
+}
+
+struct bus_type css_bus_type = {
+ .name = "css",
+ .match = &css_bus_match,
+};
+
+subsys_initcall(init_channel_subsystem);
+
+/*
+ * Register root devices for some drivers. The release function must not be
+ * in the device drivers, so we do it here.
+ */
+static void
+s390_root_dev_release(struct device *dev)
+{
+ kfree(dev);
+}
+
+struct device *
+s390_root_dev_register(const char *name)
+{
+ struct device *dev;
+ int ret;
+
+ if (!strlen(name))
+ return ERR_PTR(-EINVAL);
+ dev = kmalloc(sizeof(struct device), GFP_KERNEL);
+ if (!dev)
+ return ERR_PTR(-ENOMEM);
+ memset(dev, 0, sizeof(struct device));
+ strncpy(dev->bus_id, name, min(strlen(name), (size_t)BUS_ID_SIZE));
+ dev->release = s390_root_dev_release;
+ ret = device_register(dev);
+ if (ret) {
+ kfree(dev);
+ return ERR_PTR(ret);
+ }
+ return dev;
+}
+
+void
+s390_root_dev_unregister(struct device *dev)
+{
+ if (dev)
+ device_unregister(dev);
+}
+
+int
+css_enqueue_subchannel_slow(unsigned long schid)
+{
+ struct slow_subchannel *new_slow_sch;
+ unsigned long flags;
+
+ new_slow_sch = kmalloc(sizeof(struct slow_subchannel), GFP_ATOMIC);
+ if (!new_slow_sch)
+ return -ENOMEM;
+ memset(new_slow_sch, 0, sizeof(struct slow_subchannel));
+ new_slow_sch->schid = schid;
+ spin_lock_irqsave(&slow_subchannel_lock, flags);
+ list_add_tail(&new_slow_sch->slow_list, &slow_subchannels_head);
+ spin_unlock_irqrestore(&slow_subchannel_lock, flags);
+ return 0;
+}
+
+void
+css_clear_subchannel_slow_list(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&slow_subchannel_lock, flags);
+ while (!list_empty(&slow_subchannels_head)) {
+ struct slow_subchannel *slow_sch =
+ list_entry(slow_subchannels_head.next,
+ struct slow_subchannel, slow_list);
+
+ list_del_init(slow_subchannels_head.next);
+ kfree(slow_sch);
+ }
+ spin_unlock_irqrestore(&slow_subchannel_lock, flags);
+}
+
+
+
+int
+css_slow_subchannels_exist(void)
+{
+ return (!list_empty(&slow_subchannels_head));
+}
+
+MODULE_LICENSE("GPL");
+EXPORT_SYMBOL(css_bus_type);
+EXPORT_SYMBOL(s390_root_dev_register);
+EXPORT_SYMBOL(s390_root_dev_unregister);
+EXPORT_SYMBOL_GPL(css_characteristics_avail);