Merge branch 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip...
[pandora-kernel.git] / drivers / s390 / cio / css.c
index a769565..46c021d 100644 (file)
@@ -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);