1 files changed, 124 insertions, 159 deletions

diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index a76956512b2d..46c021d880dc 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -2,8 +2,7 @@
  *  drivers/s390/cio/css.c
  *  driver for channel subsystem
  *
- *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
- *                       IBM Corporation
+ *    Copyright IBM Corp. 2002,2008
  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
  *               Cornelia Huck (cornelia.huck@de.ibm.com)
  */
@@ -14,7 +13,9 @@
 #include <linux/errno.h>
 #include <linux/list.h>
 #include <linux/reboot.h>
+#include <asm/isc.h>
 
+#include "../s390mach.h"
 #include "css.h"
 #include "cio.h"
 #include "cio_debug.h"
@@ -30,8 +31,6 @@ static int max_ssid = 0;
 
 struct channel_subsystem *channel_subsystems[__MAX_CSSID + 1];
 
-int css_characteristics_avail = 0;
-
 int
 for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *data)
 {
@@ -121,25 +120,6 @@ css_alloc_subchannel(struct subchannel_id schid)
                 kfree(sch);
                 return ERR_PTR(ret);
         }
-
-        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)(addr_t)sch;
-        ret = cio_modify(sch);
-        if (ret) {
-                kfree(sch->lock);
-                kfree(sch);
-                return ERR_PTR(ret);
-        }
         return sch;
 }
 
@@ -177,12 +157,18 @@ static int css_sch_device_register(struct subchannel *sch)
         return ret;
 }
 
+/**
+ * css_sch_device_unregister - unregister a subchannel
+ * @sch: subchannel to be unregistered
+ */
 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);
 
 static void ssd_from_pmcw(struct chsc_ssd_info *ssd, struct pmcw *pmcw)
 {
@@ -229,6 +215,41 @@ void css_update_ssd_info(struct subchannel *sch)
         }
 }
 
+static ssize_t type_show(struct device *dev, struct device_attribute *attr,
+                         char *buf)
+{
+        struct subchannel *sch = to_subchannel(dev);
+
+        return sprintf(buf, "%01x\n", sch->st);
+}
+
+static DEVICE_ATTR(type, 0444, type_show, NULL);
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
+                             char *buf)
+{
+        struct subchannel *sch = to_subchannel(dev);
+
+        return sprintf(buf, "css:t%01X\n", sch->st);
+}
+
+static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
+
+static struct attribute *subch_attrs[] = {
+        &dev_attr_type.attr,
+        &dev_attr_modalias.attr,
+        NULL,
+};
+
+static struct attribute_group subch_attr_group = {
+        .attrs = subch_attrs,
+};
+
+static struct attribute_group *default_subch_attr_groups[] = {
+        &subch_attr_group,
+        NULL,
+};
+
 static int css_register_subchannel(struct subchannel *sch)
 {
         int ret;
@@ -237,16 +258,17 @@ static int css_register_subchannel(struct subchannel *sch)
         sch->dev.parent = &channel_subsystems[0]->device;
         sch->dev.bus = &css_bus_type;
         sch->dev.release = &css_subchannel_release;
-        sch->dev.groups = subch_attr_groups;
+        sch->dev.groups = default_subch_attr_groups;
         /*
          * We don't want to generate uevents for I/O subchannels that don't
          * have a working ccw device behind them since they will be
          * unregistered before they can be used anyway, so we delay the add
          * uevent until after device recognition was successful.
+         * Note that we suppress the uevent for all subchannel types;
+         * the subchannel driver can decide itself when it wants to inform
+         * userspace of its existence.
          */
-        if (!cio_is_console(sch->schid))
-                /* Console is special, no need to suppress. */
-                sch->dev.uevent_suppress = 1;
+        sch->dev.uevent_suppress = 1;
         css_update_ssd_info(sch);
         /* make it known to the system */
         ret = css_sch_device_register(sch);
@@ -255,10 +277,19 @@ static int css_register_subchannel(struct subchannel *sch)
                               sch->schid.ssid, sch->schid.sch_no, ret);
                 return ret;
         }
+        if (!sch->driver) {
+                /*
+                 * No driver matched. Generate the uevent now so that
+                 * a fitting driver module may be loaded based on the
+                 * modalias.
+                 */
+                sch->dev.uevent_suppress = 0;
+                kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
+        }
         return ret;
 }
 
-static int css_probe_device(struct subchannel_id schid)
+int css_probe_device(struct subchannel_id schid)
 {
         int ret;
         struct subchannel *sch;
@@ -301,116 +332,12 @@ int css_sch_is_valid(struct schib *schib)
 {
         if ((schib->pmcw.st == SUBCHANNEL_TYPE_IO) && !schib->pmcw.dnv)
                 return 0;
+        if ((schib->pmcw.st == SUBCHANNEL_TYPE_MSG) && !schib->pmcw.w)
+                return 0;
         return 1;
 }
 EXPORT_SYMBOL_GPL(css_sch_is_valid);
 
-static int css_get_subchannel_status(struct subchannel *sch)
-{
-        struct schib schib;
-
-        if (stsch(sch->schid, &schib))
-                return CIO_GONE;
-        if (!css_sch_is_valid(&schib))
-                return CIO_GONE;
-        if (sch->schib.pmcw.dnv && (schib.pmcw.dev != sch->schib.pmcw.dev))
-                return CIO_REVALIDATE;
-        if (!sch->lpm)
-                return CIO_NO_PATH;
-        return CIO_OPER;
-}
-
-static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
-{
-        int event, ret, disc;
-        unsigned long flags;
-        enum { NONE, UNREGISTER, UNREGISTER_PROBE, REPROBE } action;
-
-        spin_lock_irqsave(sch->lock, flags);
-        disc = device_is_disconnected(sch);
-        if (disc && slow) {
-                /* Disconnected devices are evaluated directly only.*/
-                spin_unlock_irqrestore(sch->lock, flags);
-                return 0;
-        }
-        /* No interrupt after machine check - kill pending timers. */
-        device_kill_pending_timer(sch);
-        if (!disc && !slow) {
-                /* Non-disconnected devices are evaluated on the slow path. */
-                spin_unlock_irqrestore(sch->lock, flags);
-                return -EAGAIN;
-        }
-        event = css_get_subchannel_status(sch);
-        CIO_MSG_EVENT(4, "Evaluating schid 0.%x.%04x, event %d, %s, %s path.\n",
-                      sch->schid.ssid, sch->schid.sch_no, event,
-                      disc ? "disconnected" : "normal",
-                      slow ? "slow" : "fast");
-        /* Analyze subchannel status. */
-        action = NONE;
-        switch (event) {
-        case CIO_NO_PATH:
-                if (disc) {
-                        /* Check if paths have become available. */
-                        action = REPROBE;
-                        break;
-                }
-                /* fall through */
-        case CIO_GONE:
-                /* Prevent unwanted effects when opening lock. */
-                cio_disable_subchannel(sch);
-                device_set_disconnected(sch);
-                /* Ask driver what to do with device. */
-                action = UNREGISTER;
-                if (sch->driver && sch->driver->notify) {
-                        spin_unlock_irqrestore(sch->lock, flags);
-                        ret = sch->driver->notify(sch, event);
-                        spin_lock_irqsave(sch->lock, flags);
-                        if (ret)
-                                action = NONE;
-                }
-                break;
-        case CIO_REVALIDATE:
-                /* Device will be removed, so no notify necessary. */
-                if (disc)
-                        /* Reprobe because immediate unregister might block. */
-                        action = REPROBE;
-                else
-                        action = UNREGISTER_PROBE;
-                break;
-        case CIO_OPER:
-                if (disc)
-                        /* Get device operational again. */
-                        action = REPROBE;
-                break;
-        }
-        /* Perform action. */
-        ret = 0;
-        switch (action) {
-        case UNREGISTER:
-        case UNREGISTER_PROBE:
-                /* Unregister device (will use subchannel lock). */
-                spin_unlock_irqrestore(sch->lock, flags);
-                css_sch_device_unregister(sch);
-                spin_lock_irqsave(sch->lock, flags);
-
-                /* Reset intparm to zeroes. */
-                sch->schib.pmcw.intparm = 0;
-                cio_modify(sch);
-                break;
-        case REPROBE:
-                device_trigger_reprobe(sch);
-                break;
-        default:
-                break;
-        }
-        spin_unlock_irqrestore(sch->lock, flags);
-        /* Probe if necessary. */
-        if (action == UNREGISTER_PROBE)
-                ret = css_probe_device(sch->schid);
-
-        return ret;
-}
-
 static int css_evaluate_new_subchannel(struct subchannel_id schid, int slow)
 {
         struct schib schib;
@@ -429,6 +356,21 @@ static int css_evaluate_new_subchannel(struct subchannel_id schid, int slow)
         return css_probe_device(schid);
 }
 
+static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
+{
+        int ret = 0;
+
+        if (sch->driver) {
+                if (sch->driver->sch_event)
+                        ret = sch->driver->sch_event(sch, slow);
+                else
+                        dev_dbg(&sch->dev,
+                                "Got subchannel machine check but "
+                                "no sch_event handler provided.\n");
+        }
+        return ret;
+}
+
 static void css_evaluate_subchannel(struct subchannel_id schid, int slow)
 {
         struct subchannel *sch;
@@ -596,18 +538,29 @@ EXPORT_SYMBOL_GPL(css_schedule_reprobe);
 /*
  * Called from the machine check handler for subchannel report words.
  */
-void css_process_crw(int rsid1, int rsid2)
+static void css_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
 {
         struct subchannel_id mchk_schid;
 
-        CIO_CRW_EVENT(2, "source is subchannel %04X, subsystem id %x\n",
-                      rsid1, rsid2);
+        if (overflow) {
+                css_schedule_eval_all();
+                return;
+        }
+        CIO_CRW_EVENT(2, "CRW0 reports slct=%d, oflw=%d, "
+                      "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
+                      crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
+                      crw0->erc, crw0->rsid);
+        if (crw1)
+                CIO_CRW_EVENT(2, "CRW1 reports slct=%d, oflw=%d, "
+                              "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
+                              crw1->slct, crw1->oflw, crw1->chn, crw1->rsc,
+                              crw1->anc, crw1->erc, crw1->rsid);
         init_subchannel_id(&mchk_schid);
-        mchk_schid.sch_no = rsid1;
-        if (rsid2 != 0)
-                mchk_schid.ssid = (rsid2 >> 8) & 3;
+        mchk_schid.sch_no = crw0->rsid;
+        if (crw1)
+                mchk_schid.ssid = (crw1->rsid >> 8) & 3;
 
-        /* 
+        /*
          * 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.
@@ -658,7 +611,7 @@ __init_channel_subsystem(struct subchannel_id schid, void *data)
 static void __init
 css_generate_pgid(struct channel_subsystem *css, u32 tod_high)
 {
-        if (css_characteristics_avail && css_general_characteristics.mcss) {
+        if (css_general_characteristics.mcss) {
                 css->global_pgid.pgid_high.ext_cssid.version = 0x80;
                 css->global_pgid.pgid_high.ext_cssid.cssid = css->cssid;
         } else {
@@ -795,8 +748,6 @@ init_channel_subsystem (void)
         ret = chsc_determine_css_characteristics();
         if (ret == -ENOMEM)
                 goto out; /* No need to continue. */
-        if (ret == 0)
-                css_characteristics_avail = 1;
 
         ret = chsc_alloc_sei_area();
         if (ret)
@@ -806,6 +757,10 @@ init_channel_subsystem (void)
         if (ret)
                 goto out;
 
+        ret = s390_register_crw_handler(CRW_RSC_SCH, css_process_crw);
+        if (ret)
+                goto out;
+
         if ((ret = bus_register(&css_bus_type)))
                 goto out;
 
@@ -836,8 +791,7 @@ init_channel_subsystem (void)
                 ret = device_register(&css->device);
                 if (ret)
                         goto out_free_all;
-                if (css_characteristics_avail &&
-                    css_chsc_characteristics.secm) {
+                if (css_chsc_characteristics.secm) {
                         ret = device_create_file(&css->device,
                                                  &dev_attr_cm_enable);
                         if (ret)
@@ -852,7 +806,8 @@ init_channel_subsystem (void)
                 goto out_pseudo;
         css_init_done = 1;
 
-        ctl_set_bit(6, 28);
+        /* Enable default isc for I/O subchannels. */
+        isc_register(IO_SCH_ISC);
 
         for_each_subchannel(__init_channel_subsystem, NULL);
         return 0;
@@ -875,7 +830,7 @@ out_unregister:
                 i--;
                 css = channel_subsystems[i];
                 device_unregister(&css->pseudo_subchannel->dev);
-                if (css_characteristics_avail && css_chsc_characteristics.secm)
+                if (css_chsc_characteristics.secm)
                         device_remove_file(&css->device,
                                            &dev_attr_cm_enable);
                 device_unregister(&css->device);
@@ -883,6 +838,7 @@ out_unregister:
 out_bus:
         bus_unregister(&css_bus_type);
 out:
+        s390_unregister_crw_handler(CRW_RSC_CSS);
         chsc_free_sei_area();
         kfree(slow_subchannel_set);
         printk(KERN_WARNING"cio: failed to initialize css driver (%d)!\n",
@@ -895,19 +851,16 @@ int sch_is_pseudo_sch(struct subchannel *sch)
         return sch == to_css(sch->dev.parent)->pseudo_subchannel;
 }
 
-/*
- * 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)
+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;
 }
@@ -945,12 +898,25 @@ static void css_shutdown(struct device *dev)
                 sch->driver->shutdown(sch);
 }
 
+static int css_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+        struct subchannel *sch = to_subchannel(dev);
+        int ret;
+
+        ret = add_uevent_var(env, "ST=%01X", sch->st);
+        if (ret)
+                return ret;
+        ret = add_uevent_var(env, "MODALIAS=css:t%01X", sch->st);
+        return ret;
+}
+
 struct bus_type css_bus_type = {
         .name     = "css",
         .match    = css_bus_match,
         .probe    = css_probe,
         .remove   = css_remove,
         .shutdown = css_shutdown,
+        .uevent   = css_uevent,
 };
 
 /**
@@ -985,4 +951,3 @@ subsys_initcall(init_channel_subsystem);
 
 MODULE_LICENSE("GPL");
 EXPORT_SYMBOL(css_bus_type);
-EXPORT_SYMBOL_GPL(css_characteristics_avail);