Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / drivers / s390 / cio / chsc.c
index b35fe12..72187e5 100644 (file)
@@ -1,12 +1,11 @@
 /*
  *  drivers/s390/cio/chsc.c
  *   S/390 common I/O routines -- channel subsystem call
- *   $Revision: 1.119 $
  *
  *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
  *                           IBM Corporation
  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
- *              Cornelia Huck (cohuck@de.ibm.com)
+ *              Cornelia Huck (cornelia.huck@de.ibm.com)
  *              Arnd Bergmann (arndb@de.ibm.com)
  */
 
@@ -24,8 +23,6 @@
 #include "ioasm.h"
 #include "chsc.h"
 
-static struct channel_path *chps[NR_CHPIDS];
-
 static void *sei_page;
 
 static int new_channel_path(int chpid);
@@ -33,13 +30,13 @@ static int new_channel_path(int chpid);
 static inline void
 set_chp_logically_online(int chp, int onoff)
 {
-       chps[chp]->state = onoff;
+       css[0]->chps[chp]->state = onoff;
 }
 
 static int
 get_chp_status(int chp)
 {
-       return (chps[chp] ? chps[chp]->state : -ENODEV);
+       return (css[0]->chps[chp] ? css[0]->chps[chp]->state : -ENODEV);
 }
 
 void
@@ -77,7 +74,9 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
 
        struct {
                struct chsc_header request;
-               u16 reserved1;
+               u16 reserved1a:10;
+               u16 ssid:2;
+               u16 reserved1b:4;
                u16 f_sch;        /* first subchannel */
                u16 reserved2;
                u16 l_sch;        /* last subchannel */
@@ -99,13 +98,12 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
 
        ssd_area = page;
 
-       ssd_area->request = (struct chsc_header) {
-               .length = 0x0010,
-               .code   = 0x0004,
-       };
+       ssd_area->request.length = 0x0010;
+       ssd_area->request.code = 0x0004;
 
-       ssd_area->f_sch = sch->irq;
-       ssd_area->l_sch = sch->irq;
+       ssd_area->ssid = sch->schid.ssid;
+       ssd_area->f_sch = sch->schid.sch_no;
+       ssd_area->l_sch = sch->schid.sch_no;
 
        ccode = chsc(ssd_area);
        if (ccode > 0) {
@@ -147,7 +145,8 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
         */
        if (ssd_area->st > 3) { /* uhm, that looks strange... */
                CIO_CRW_EVENT(0, "Strange subchannel type %d"
-                             " for sch %04x\n", ssd_area->st, sch->irq);
+                             " for sch 0.%x.%04x\n", ssd_area->st,
+                             sch->schid.ssid, sch->schid.sch_no);
                /*
                 * There may have been a new subchannel type defined in the
                 * time since this code was written; since we don't know which
@@ -156,8 +155,9 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
                return 0;
        } else {
                const char *type[4] = {"I/O", "chsc", "message", "ADM"};
-               CIO_CRW_EVENT(6, "ssd: sch %04x is %s subchannel\n",
-                             sch->irq, type[ssd_area->st]);
+               CIO_CRW_EVENT(6, "ssd: sch 0.%x.%04x is %s subchannel\n",
+                             sch->schid.ssid, sch->schid.sch_no,
+                             type[ssd_area->st]);
 
                sch->ssd_info.valid = 1;
                sch->ssd_info.type = ssd_area->st;
@@ -218,21 +218,21 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
        int j;
        int mask;
        struct subchannel *sch;
-       __u8 *chpid;
+       struct channel_path *chpid;
        struct schib schib;
 
        sch = to_subchannel(dev);
        chpid = data;
        for (j = 0; j < 8; j++)
-               if (sch->schib.pmcw.chpid[j] == *chpid)
+               if (sch->schib.pmcw.chpid[j] == chpid->id)
                        break;
        if (j >= 8)
                return 0;
 
        mask = 0x80 >> j;
-       spin_lock(&sch->lock);
+       spin_lock_irq(&sch->lock);
 
-       stsch(sch->irq, &schib);
+       stsch(sch->schid, &schib);
        if (!schib.pmcw.dnv)
                goto out_unreg;
        memcpy(&sch->schib, &schib, sizeof(struct schib));
@@ -242,28 +242,10 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
        if (sch->vpm == mask)
                goto out_unreg;
 
-       if ((sch->schib.scsw.actl & (SCSW_ACTL_CLEAR_PEND |
-                                    SCSW_ACTL_HALT_PEND |
-                                    SCSW_ACTL_START_PEND |
-                                    SCSW_ACTL_RESUME_PEND)) &&
-           (sch->schib.pmcw.lpum == mask)) {
-               int cc = cio_cancel(sch);
-               
-               if (cc == -ENODEV)
-                       goto out_unreg;
-
-               if (cc == -EINVAL) {
-                       cc = cio_clear(sch);
-                       if (cc == -ENODEV)
-                               goto out_unreg;
-                       /* Call handler. */
-                       if (sch->driver && sch->driver->termination)
-                               sch->driver->termination(&sch->dev);
-                       goto out_unlock;
-               }
-       } else if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
-                  (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
-                  (sch->schib.pmcw.lpum == mask)) {
+       if ((sch->schib.scsw.actl & SCSW_ACTL_DEVACT) &&
+           (sch->schib.scsw.actl & SCSW_ACTL_SCHACT) &&
+           (sch->schib.pmcw.lpum == mask) &&
+           (sch->vpm == 0)) {
                int cc;
 
                cc = cio_clear(sch);
@@ -279,12 +261,12 @@ s390_subchannel_remove_chpid(struct device *dev, void *data)
        if (sch->driver && sch->driver->verify)
                sch->driver->verify(&sch->dev);
 out_unlock:
-       spin_unlock(&sch->lock);
+       spin_unlock_irq(&sch->lock);
        return 0;
 out_unreg:
-       spin_unlock(&sch->lock);
+       spin_unlock_irq(&sch->lock);
        sch->lpm = 0;
-       if (css_enqueue_subchannel_slow(sch->irq)) {
+       if (css_enqueue_subchannel_slow(sch->schid)) {
                css_clear_subchannel_slow_list();
                need_rescan = 1;
        }
@@ -295,23 +277,30 @@ static inline void
 s390_set_chpid_offline( __u8 chpid)
 {
        char dbf_txt[15];
+       struct device *dev;
 
        sprintf(dbf_txt, "chpr%x", chpid);
        CIO_TRACE_EVENT(2, dbf_txt);
 
        if (get_chp_status(chpid) <= 0)
                return;
-
-       bus_for_each_dev(&css_bus_type, NULL, &chpid,
+       dev = get_device(&css[0]->chps[chpid]->dev);
+       bus_for_each_dev(&css_bus_type, NULL, to_channelpath(dev),
                         s390_subchannel_remove_chpid);
 
        if (need_rescan || css_slow_subchannels_exist())
                queue_work(slow_path_wq, &slow_path_work);
+       put_device(dev);
 }
 
+struct res_acc_data {
+       struct channel_path *chp;
+       u32 fla_mask;
+       u16 fla;
+};
+
 static int
-s390_process_res_acc_sch(u8 chpid, __u16 fla, u32 fla_mask,
-                        struct subchannel *sch)
+s390_process_res_acc_sch(struct res_acc_data *res_data, struct subchannel *sch)
 {
        int found;
        int chp;
@@ -323,8 +312,9 @@ s390_process_res_acc_sch(u8 chpid, __u16 fla, u32 fla_mask,
                 * check if chpid is in information updated by ssd
                 */
                if (sch->ssd_info.valid &&
-                   sch->ssd_info.chpid[chp] == chpid &&
-                   (sch->ssd_info.fla[chp] & fla_mask) == fla) {
+                   sch->ssd_info.chpid[chp] == res_data->chp->id &&
+                   (sch->ssd_info.fla[chp] & res_data->fla_mask)
+                   == res_data->fla) {
                        found = 1;
                        break;
                }
@@ -337,24 +327,87 @@ s390_process_res_acc_sch(u8 chpid, __u16 fla, u32 fla_mask,
         * new path information and eventually check for logically
         * offline chpids.
         */
-       ccode = stsch(sch->irq, &sch->schib);
+       ccode = stsch(sch->schid, &sch->schib);
        if (ccode > 0)
                return 0;
 
        return 0x80 >> chp;
 }
 
+static inline int
+s390_process_res_acc_new_sch(struct subchannel_id schid)
+{
+       struct schib schib;
+       int ret;
+       /*
+        * We don't know the device yet, but since a path
+        * may be available now to the device we'll have
+        * to do recognition again.
+        * Since we don't have any idea about which chpid
+        * that beast may be on we'll have to do a stsch
+        * on all devices, grr...
+        */
+       if (stsch_err(schid, &schib))
+               /* We're through */
+               return need_rescan ? -EAGAIN : -ENXIO;
+
+       /* Put it on the slow path. */
+       ret = css_enqueue_subchannel_slow(schid);
+       if (ret) {
+               css_clear_subchannel_slow_list();
+               need_rescan = 1;
+               return -EAGAIN;
+       }
+       return 0;
+}
+
 static int
-s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
+__s390_process_res_acc(struct subchannel_id schid, void *data)
 {
+       int chp_mask, old_lpm;
+       struct res_acc_data *res_data;
        struct subchannel *sch;
-       int irq, rc;
+
+       res_data = (struct res_acc_data *)data;
+       sch = get_subchannel_by_schid(schid);
+       if (!sch)
+               /* Check if a subchannel is newly available. */
+               return s390_process_res_acc_new_sch(schid);
+
+       spin_lock_irq(&sch->lock);
+
+       chp_mask = s390_process_res_acc_sch(res_data, sch);
+
+       if (chp_mask == 0) {
+               spin_unlock_irq(&sch->lock);
+               return 0;
+       }
+       old_lpm = sch->lpm;
+       sch->lpm = ((sch->schib.pmcw.pim &
+                    sch->schib.pmcw.pam &
+                    sch->schib.pmcw.pom)
+                   | chp_mask) & sch->opm;
+       if (!old_lpm && sch->lpm)
+               device_trigger_reprobe(sch);
+       else if (sch->driver && sch->driver->verify)
+               sch->driver->verify(&sch->dev);
+
+       spin_unlock_irq(&sch->lock);
+       put_device(&sch->dev);
+       return (res_data->fla_mask == 0xffff) ? -ENODEV : 0;
+}
+
+
+static int
+s390_process_res_acc (struct res_acc_data *res_data)
+{
+       int rc;
        char dbf_txt[15];
 
-       sprintf(dbf_txt, "accpr%x", chpid);
+       sprintf(dbf_txt, "accpr%x", res_data->chp->id);
        CIO_TRACE_EVENT( 2, dbf_txt);
-       if (fla != 0) {
-               sprintf(dbf_txt, "fla%x", fla);
+       if (res_data->fla != 0) {
+               sprintf(dbf_txt, "fla%x", res_data->fla);
                CIO_TRACE_EVENT( 2, dbf_txt);
        }
 
@@ -365,74 +418,11 @@ s390_process_res_acc (u8 chpid, __u16 fla, u32 fla_mask)
         * The more information we have (info), the less scanning
         * will we have to do.
         */
-
-       if (!get_chp_status(chpid))
-               return 0; /* no need to do the rest */
-
-       rc = 0;
-       for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
-               int chp_mask, old_lpm;
-
-               sch = get_subchannel_by_schid(irq);
-               if (!sch) {
-                       struct schib schib;
-                       int ret;
-                       /*
-                        * We don't know the device yet, but since a path
-                        * may be available now to the device we'll have
-                        * to do recognition again.
-                        * Since we don't have any idea about which chpid
-                        * that beast may be on we'll have to do a stsch
-                        * on all devices, grr...
-                        */
-                       if (stsch(irq, &schib)) {
-                               /* We're through */
-                               if (need_rescan)
-                                       rc = -EAGAIN;
-                               break;
-                       }
-                       if (need_rescan) {
-                               rc = -EAGAIN;
-                               continue;
-                       }
-                       /* Put it on the slow path. */
-                       ret = css_enqueue_subchannel_slow(irq);
-                       if (ret) {
-                               css_clear_subchannel_slow_list();
-                               need_rescan = 1;
-                       }
-                       rc = -EAGAIN;
-                       continue;
-               }
-       
-               spin_lock_irq(&sch->lock);
-
-               chp_mask = s390_process_res_acc_sch(chpid, fla, fla_mask, sch);
-
-               if (chp_mask == 0) {
-
-                       spin_unlock_irq(&sch->lock);
-
-                       if (fla_mask != 0)
-                               break;
-                       else
-                               continue;
-               }
-               old_lpm = sch->lpm;
-               sch->lpm = ((sch->schib.pmcw.pim &
-                            sch->schib.pmcw.pam &
-                            sch->schib.pmcw.pom)
-                           | chp_mask) & sch->opm;
-               if (!old_lpm && sch->lpm)
-                       device_trigger_reprobe(sch);
-               else if (sch->driver && sch->driver->verify)
-                       sch->driver->verify(&sch->dev);
-
-               spin_unlock_irq(&sch->lock);
-               put_device(&sch->dev);
-               if (fla_mask != 0)
-                       break;
-       }
+       rc = for_each_subchannel(__s390_process_res_acc, res_data);
+       if (css_slow_subchannels_exist())
+               rc = -EAGAIN;
+       else if (rc != -EAGAIN)
+               rc = 0;
        return rc;
 }
 
@@ -470,6 +460,7 @@ int
 chsc_process_crw(void)
 {
        int chpid, ret;
+       struct res_acc_data res_data;
        struct {
                struct chsc_header request;
                u32 reserved1;
@@ -503,12 +494,11 @@ chsc_process_crw(void)
        ret = 0;
        do {
                int ccode, status;
+               struct device *dev;
                memset(sei_area, 0, sizeof(*sei_area));
-
-               sei_area->request = (struct chsc_header) {
-                       .length = 0x0010,
-                       .code   = 0x000e,
-               };
+               memset(&res_data, 0, sizeof(struct res_acc_data));
+               sei_area->request.length = 0x0010;
+               sei_area->request.code = 0x000e;
 
                ccode = chsc(sei_area);
                if (ccode > 0)
@@ -577,26 +567,25 @@ chsc_process_crw(void)
                        if (status < 0)
                                new_channel_path(sei_area->rsid);
                        else if (!status)
-                               return 0;
-                       if ((sei_area->vf & 0x80) == 0) {
-                               pr_debug("chpid: %x\n", sei_area->rsid);
-                               ret = s390_process_res_acc(sei_area->rsid,
-                                                          0, 0);
-                       } else if ((sei_area->vf & 0xc0) == 0x80) {
-                               pr_debug("chpid: %x link addr: %x\n",
-                                        sei_area->rsid, sei_area->fla);
-                               ret = s390_process_res_acc(sei_area->rsid,
-                                                          sei_area->fla,
-                                                          0xff00);
-                       } else if ((sei_area->vf & 0xc0) == 0xc0) {
-                               pr_debug("chpid: %x full link addr: %x\n",
-                                        sei_area->rsid, sei_area->fla);
-                               ret = s390_process_res_acc(sei_area->rsid,
-                                                          sei_area->fla,
-                                                          0xffff);
+                               break;
+                       dev = get_device(&css[0]->chps[sei_area->rsid]->dev);
+                       res_data.chp = to_channelpath(dev);
+                       pr_debug("chpid: %x", sei_area->rsid);
+                       if ((sei_area->vf & 0xc0) != 0) {
+                               res_data.fla = sei_area->fla;
+                               if ((sei_area->vf & 0xc0) == 0xc0) {
+                                       pr_debug(" full link addr: %x",
+                                                sei_area->fla);
+                                       res_data.fla_mask = 0xffff;
+                               } else {
+                                       pr_debug(" link addr: %x",
+                                                sei_area->fla);
+                                       res_data.fla_mask = 0xff00;
+                               }
                        }
-                       pr_debug("\n");
-                       
+                       ret = s390_process_res_acc(&res_data);
+                       pr_debug("\n\n");
+                       put_device(dev);
                        break;
                        
                default: /* other stuff */
@@ -608,12 +597,72 @@ chsc_process_crw(void)
        return ret;
 }
 
+static inline int
+__chp_add_new_sch(struct subchannel_id schid)
+{
+       struct schib schib;
+       int ret;
+
+       if (stsch(schid, &schib))
+               /* We're through */
+               return need_rescan ? -EAGAIN : -ENXIO;
+
+       /* Put it on the slow path. */
+       ret = css_enqueue_subchannel_slow(schid);
+       if (ret) {
+               css_clear_subchannel_slow_list();
+               need_rescan = 1;
+               return -EAGAIN;
+       }
+       return 0;
+}
+
+
 static int
-chp_add(int chpid)
+__chp_add(struct subchannel_id schid, void *data)
 {
+       int i;
+       struct channel_path *chp;
        struct subchannel *sch;
-       int irq, ret, rc;
+
+       chp = (struct channel_path *)data;
+       sch = get_subchannel_by_schid(schid);
+       if (!sch)
+               /* Check if the subchannel is now available. */
+               return __chp_add_new_sch(schid);
+       spin_lock_irq(&sch->lock);
+       for (i=0; i<8; i++)
+               if (sch->schib.pmcw.chpid[i] == chp->id) {
+                       if (stsch(sch->schid, &sch->schib) != 0) {
+                               /* Endgame. */
+                               spin_unlock_irq(&sch->lock);
+                               return -ENXIO;
+                       }
+                       break;
+               }
+       if (i==8) {
+               spin_unlock_irq(&sch->lock);
+               return 0;
+       }
+       sch->lpm = ((sch->schib.pmcw.pim &
+                    sch->schib.pmcw.pam &
+                    sch->schib.pmcw.pom)
+                   | 0x80 >> i) & sch->opm;
+
+       if (sch->driver && sch->driver->verify)
+               sch->driver->verify(&sch->dev);
+
+       spin_unlock_irq(&sch->lock);
+       put_device(&sch->dev);
+       return 0;
+}
+
+static int
+chp_add(int chpid)
+{
+       int rc;
        char dbf_txt[15];
+       struct device *dev;
 
        if (!get_chp_status(chpid))
                return 0; /* no need to do the rest */
@@ -621,59 +670,13 @@ chp_add(int chpid)
        sprintf(dbf_txt, "cadd%x", chpid);
        CIO_TRACE_EVENT(2, dbf_txt);
 
-       rc = 0;
-       for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
-               int i;
-
-               sch = get_subchannel_by_schid(irq);
-               if (!sch) {
-                       struct schib schib;
-
-                       if (stsch(irq, &schib)) {
-                               /* We're through */
-                               if (need_rescan)
-                                       rc = -EAGAIN;
-                               break;
-                       }
-                       if (need_rescan) {
-                               rc = -EAGAIN;
-                               continue;
-                       }
-                       /* Put it on the slow path. */
-                       ret = css_enqueue_subchannel_slow(irq);
-                       if (ret) {
-                               css_clear_subchannel_slow_list();
-                               need_rescan = 1;
-                       }
-                       rc = -EAGAIN;
-                       continue;
-               }
-       
-               spin_lock(&sch->lock);
-               for (i=0; i<8; i++)
-                       if (sch->schib.pmcw.chpid[i] == chpid) {
-                               if (stsch(sch->irq, &sch->schib) != 0) {
-                                       /* Endgame. */
-                                       spin_unlock(&sch->lock);
-                                       return rc;
-                               }
-                               break;
-                       }
-               if (i==8) {
-                       spin_unlock(&sch->lock);
-                       return rc;
-               }
-               sch->lpm = ((sch->schib.pmcw.pim &
-                            sch->schib.pmcw.pam &
-                            sch->schib.pmcw.pom)
-                           | 0x80 >> i) & sch->opm;
-
-               if (sch->driver && sch->driver->verify)
-                       sch->driver->verify(&sch->dev);
-
-               spin_unlock(&sch->lock);
-               put_device(&sch->dev);
-       }
+       dev = get_device(&css[0]->chps[chpid]->dev);
+       rc = for_each_subchannel(__chp_add, to_channelpath(dev));
+       if (css_slow_subchannels_exist())
+               rc = -EAGAIN;
+       if (rc != -EAGAIN)
+               rc = 0;
+       put_device(dev);
        return rc;
 }
 
@@ -706,7 +709,7 @@ __check_for_io_and_kill(struct subchannel *sch, int index)
        if (!device_is_online(sch))
                /* cio could be doing I/O. */
                return 0;
-       cc = stsch(sch->irq, &sch->schib);
+       cc = stsch(sch->schid, &sch->schib);
        if (cc)
                return 0;
        if (sch->schib.scsw.actl && sch->schib.pmcw.lpum == (0x80 >> index)) {
@@ -747,7 +750,7 @@ __s390_subchannel_vary_chpid(struct subchannel *sch, __u8 chpid, int on)
                         * just varied off path. Then kill it.
                         */
                        if (!__check_for_io_and_kill(sch, chp) && !sch->lpm) {
-                               if (css_enqueue_subchannel_slow(sch->irq)) {
+                               if (css_enqueue_subchannel_slow(sch->schid)) {
                                        css_clear_subchannel_slow_list();
                                        need_rescan = 1;
                                }
@@ -785,6 +788,29 @@ s390_subchannel_vary_chpid_on(struct device *dev, void *data)
        return 0;
 }
 
+static int
+__s390_vary_chpid_on(struct subchannel_id schid, void *data)
+{
+       struct schib schib;
+       struct subchannel *sch;
+
+       sch = get_subchannel_by_schid(schid);
+       if (sch) {
+               put_device(&sch->dev);
+               return 0;
+       }
+       if (stsch_err(schid, &schib))
+               /* We're through */
+               return -ENXIO;
+       /* Put it on the slow path. */
+       if (css_enqueue_subchannel_slow(schid)) {
+               css_clear_subchannel_slow_list();
+               need_rescan = 1;
+               return -EAGAIN;
+       }
+       return 0;
+}
+
 /*
  * Function: s390_vary_chpid
  * Varies the specified chpid online or offline
@@ -793,8 +819,7 @@ static int
 s390_vary_chpid( __u8 chpid, int on)
 {
        char dbf_text[15];
-       int status, irq, ret;
-       struct subchannel *sch;
+       int status;
 
        sprintf(dbf_text, on?"varyon%x":"varyoff%x", chpid);
        CIO_TRACE_EVENT( 2, dbf_text);
@@ -819,40 +844,277 @@ s390_vary_chpid( __u8 chpid, int on)
        bus_for_each_dev(&css_bus_type, NULL, &chpid, on ?
                         s390_subchannel_vary_chpid_on :
                         s390_subchannel_vary_chpid_off);
-       if (!on)
-               goto out;
-       /* Scan for new devices on varied on path. */
-       for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
-               struct schib schib;
+       if (on)
+               /* Scan for new devices on varied on path. */
+               for_each_subchannel(__s390_vary_chpid_on, NULL);
+       if (need_rescan || css_slow_subchannels_exist())
+               queue_work(slow_path_wq, &slow_path_work);
+       return 0;
+}
 
-               if (need_rescan)
-                       break;
-               sch = get_subchannel_by_schid(irq);
-               if (sch) {
-                       put_device(&sch->dev);
+/*
+ * Channel measurement related functions
+ */
+static ssize_t
+chp_measurement_chars_read(struct kobject *kobj, char *buf, loff_t off,
+                          size_t count)
+{
+       struct channel_path *chp;
+       unsigned int size;
+
+       chp = to_channelpath(container_of(kobj, struct device, kobj));
+       if (!chp->cmg_chars)
+               return 0;
+
+       size = sizeof(struct cmg_chars);
+
+       if (off > size)
+               return 0;
+       if (off + count > size)
+               count = size - off;
+       memcpy(buf, chp->cmg_chars + off, count);
+       return count;
+}
+
+static struct bin_attribute chp_measurement_chars_attr = {
+       .attr = {
+               .name = "measurement_chars",
+               .mode = S_IRUSR,
+               .owner = THIS_MODULE,
+       },
+       .size = sizeof(struct cmg_chars),
+       .read = chp_measurement_chars_read,
+};
+
+static void
+chp_measurement_copy_block(struct cmg_entry *buf,
+                          struct channel_subsystem *css, int chpid)
+{
+       void *area;
+       struct cmg_entry *entry, reference_buf;
+       int idx;
+
+       if (chpid < 128) {
+               area = css->cub_addr1;
+               idx = chpid;
+       } else {
+               area = css->cub_addr2;
+               idx = chpid - 128;
+       }
+       entry = area + (idx * sizeof(struct cmg_entry));
+       do {
+               memcpy(buf, entry, sizeof(*entry));
+               memcpy(&reference_buf, entry, sizeof(*entry));
+       } while (reference_buf.values[0] != buf->values[0]);
+}
+
+static ssize_t
+chp_measurement_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
+{
+       struct channel_path *chp;
+       struct channel_subsystem *css;
+       unsigned int size;
+
+       chp = to_channelpath(container_of(kobj, struct device, kobj));
+       css = to_css(chp->dev.parent);
+
+       size = sizeof(struct cmg_chars);
+
+       /* Only allow single reads. */
+       if (off || count < size)
+               return 0;
+       chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->id);
+       return count;
+}
+
+static struct bin_attribute chp_measurement_attr = {
+       .attr = {
+               .name = "measurement",
+               .mode = S_IRUSR,
+               .owner = THIS_MODULE,
+       },
+       .size = sizeof(struct cmg_entry),
+       .read = chp_measurement_read,
+};
+
+static void
+chsc_remove_chp_cmg_attr(struct channel_path *chp)
+{
+       sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_chars_attr);
+       sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_attr);
+}
+
+static int
+chsc_add_chp_cmg_attr(struct channel_path *chp)
+{
+       int ret;
+
+       ret = sysfs_create_bin_file(&chp->dev.kobj,
+                                   &chp_measurement_chars_attr);
+       if (ret)
+               return ret;
+       ret = sysfs_create_bin_file(&chp->dev.kobj, &chp_measurement_attr);
+       if (ret)
+               sysfs_remove_bin_file(&chp->dev.kobj,
+                                     &chp_measurement_chars_attr);
+       return ret;
+}
+
+static void
+chsc_remove_cmg_attr(struct channel_subsystem *css)
+{
+       int i;
+
+       for (i = 0; i <= __MAX_CHPID; i++) {
+               if (!css->chps[i])
                        continue;
-               }
-               if (stsch(irq, &schib))
-                       /* We're through */
-                       break;
-               /* Put it on the slow path. */
-               ret = css_enqueue_subchannel_slow(irq);
-               if (ret) {
-                       css_clear_subchannel_slow_list();
-                       need_rescan = 1;
+               chsc_remove_chp_cmg_attr(css->chps[i]);
+       }
+}
+
+static int
+chsc_add_cmg_attr(struct channel_subsystem *css)
+{
+       int i, ret;
+
+       ret = 0;
+       for (i = 0; i <= __MAX_CHPID; i++) {
+               if (!css->chps[i])
+                       continue;
+               ret = chsc_add_chp_cmg_attr(css->chps[i]);
+               if (ret)
+                       goto cleanup;
+       }
+       return ret;
+cleanup:
+       for (--i; i >= 0; i--) {
+               if (!css->chps[i])
+                       continue;
+               chsc_remove_chp_cmg_attr(css->chps[i]);
+       }
+       return ret;
+}
+
+
+static int
+__chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
+{
+       struct {
+               struct chsc_header request;
+               u32 operation_code : 2;
+               u32 : 30;
+               u32 key : 4;
+               u32 : 28;
+               u32 zeroes1;
+               u32 cub_addr1;
+               u32 zeroes2;
+               u32 cub_addr2;
+               u32 reserved[13];
+               struct chsc_header response;
+               u32 status : 8;
+               u32 : 4;
+               u32 fmt : 4;
+               u32 : 16;
+       } *secm_area;
+       int ret, ccode;
+
+       secm_area = page;
+       secm_area->request.length = 0x0050;
+       secm_area->request.code = 0x0016;
+
+       secm_area->key = PAGE_DEFAULT_KEY;
+       secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
+       secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
+
+       secm_area->operation_code = enable ? 0 : 1;
+
+       ccode = chsc(secm_area);
+       if (ccode > 0)
+               return (ccode == 3) ? -ENODEV : -EBUSY;
+
+       switch (secm_area->response.code) {
+       case 0x0001: /* Success. */
+               ret = 0;
+               break;
+       case 0x0003: /* Invalid block. */
+       case 0x0007: /* Invalid format. */
+       case 0x0008: /* Other invalid block. */
+               CIO_CRW_EVENT(2, "Error in chsc request block!\n");
+               ret = -EINVAL;
+               break;
+       case 0x0004: /* Command not provided in model. */
+               CIO_CRW_EVENT(2, "Model does not provide secm\n");
+               ret = -EOPNOTSUPP;
+               break;
+       case 0x0102: /* cub adresses incorrect */
+               CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
+               ret = -EINVAL;
+               break;
+       case 0x0103: /* key error */
+               CIO_CRW_EVENT(2, "Access key error in secm\n");
+               ret = -EINVAL;
+               break;
+       case 0x0105: /* error while starting */
+               CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
+               ret = -EIO;
+               break;
+       default:
+               CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
+                             secm_area->response.code);
+               ret = -EIO;
+       }
+       return ret;
+}
+
+int
+chsc_secm(struct channel_subsystem *css, int enable)
+{
+       void  *secm_area;
+       int ret;
+
+       secm_area = (void *)get_zeroed_page(GFP_KERNEL |  GFP_DMA);
+       if (!secm_area)
+               return -ENOMEM;
+
+       mutex_lock(&css->mutex);
+       if (enable && !css->cm_enabled) {
+               css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+               css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+               if (!css->cub_addr1 || !css->cub_addr2) {
+                       free_page((unsigned long)css->cub_addr1);
+                       free_page((unsigned long)css->cub_addr2);
+                       free_page((unsigned long)secm_area);
+                       mutex_unlock(&css->mutex);
+                       return -ENOMEM;
                }
        }
-out:
-       if (need_rescan || css_slow_subchannels_exist())
-               queue_work(slow_path_wq, &slow_path_work);
-       return 0;
+       ret = __chsc_do_secm(css, enable, secm_area);
+       if (!ret) {
+               css->cm_enabled = enable;
+               if (css->cm_enabled) {
+                       ret = chsc_add_cmg_attr(css);
+                       if (ret) {
+                               memset(secm_area, 0, PAGE_SIZE);
+                               __chsc_do_secm(css, 0, secm_area);
+                               css->cm_enabled = 0;
+                       }
+               } else
+                       chsc_remove_cmg_attr(css);
+       }
+       if (enable && !css->cm_enabled) {
+               free_page((unsigned long)css->cub_addr1);
+               free_page((unsigned long)css->cub_addr2);
+       }
+       mutex_unlock(&css->mutex);
+       free_page((unsigned long)secm_area);
+       return ret;
 }
 
 /*
  * Files for the channel path entries.
  */
 static ssize_t
-chp_status_show(struct device *dev, char *buf)
+chp_status_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
        struct channel_path *chp = container_of(dev, struct channel_path, dev);
 
@@ -863,7 +1125,7 @@ chp_status_show(struct device *dev, char *buf)
 }
 
 static ssize_t
-chp_status_write(struct device *dev, const char *buf, size_t count)
+chp_status_write(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 {
        struct channel_path *cp = container_of(dev, struct channel_path, dev);
        char cmd[10];
@@ -888,7 +1150,7 @@ chp_status_write(struct device *dev, const char *buf, size_t count)
 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
 
 static ssize_t
-chp_type_show(struct device *dev, char *buf)
+chp_type_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
        struct channel_path *chp = container_of(dev, struct channel_path, dev);
 
@@ -899,9 +1161,39 @@ chp_type_show(struct device *dev, char *buf)
 
 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
 
+static ssize_t
+chp_cmg_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct channel_path *chp = to_channelpath(dev);
+
+       if (!chp)
+               return 0;
+       if (chp->cmg == -1) /* channel measurements not available */
+               return sprintf(buf, "unknown\n");
+       return sprintf(buf, "%x\n", chp->cmg);
+}
+
+static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
+
+static ssize_t
+chp_shared_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct channel_path *chp = to_channelpath(dev);
+
+       if (!chp)
+               return 0;
+       if (chp->shared == -1) /* channel measurements not available */
+               return sprintf(buf, "unknown\n");
+       return sprintf(buf, "%x\n", chp->shared);
+}
+
+static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
+
 static struct attribute * chp_attrs[] = {
        &dev_attr_status.attr,
        &dev_attr_type.attr,
+       &dev_attr_cmg.attr,
+       &dev_attr_shared.attr,
        NULL,
 };
 
@@ -940,10 +1232,8 @@ chsc_determine_channel_path_description(int chpid,
        if (!scpd_area)
                return -ENOMEM;
 
-       scpd_area->request = (struct chsc_header) {
-               .length = 0x0010,
-               .code   = 0x0002,
-       };
+       scpd_area->request.length = 0x0010;
+       scpd_area->request.code = 0x0002;
 
        scpd_area->first_chpid = chpid;
        scpd_area->last_chpid = chpid;
@@ -980,6 +1270,111 @@ out:
        return ret;
 }
 
+static void
+chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
+                         struct cmg_chars *chars)
+{
+       switch (chp->cmg) {
+       case 2:
+       case 3:
+               chp->cmg_chars = kmalloc(sizeof(struct cmg_chars),
+                                        GFP_KERNEL);
+               if (chp->cmg_chars) {
+                       int i, mask;
+                       struct cmg_chars *cmg_chars;
+
+                       cmg_chars = chp->cmg_chars;
+                       for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
+                               mask = 0x80 >> (i + 3);
+                               if (cmcv & mask)
+                                       cmg_chars->values[i] = chars->values[i];
+                               else
+                                       cmg_chars->values[i] = 0;
+                       }
+               }
+               break;
+       default:
+               /* No cmg-dependent data. */
+               break;
+       }
+}
+
+static int
+chsc_get_channel_measurement_chars(struct channel_path *chp)
+{
+       int ccode, ret;
+
+       struct {
+               struct chsc_header request;
+               u32 : 24;
+               u32 first_chpid : 8;
+               u32 : 24;
+               u32 last_chpid : 8;
+               u32 zeroes1;
+               struct chsc_header response;
+               u32 zeroes2;
+               u32 not_valid : 1;
+               u32 shared : 1;
+               u32 : 22;
+               u32 chpid : 8;
+               u32 cmcv : 5;
+               u32 : 11;
+               u32 cmgq : 8;
+               u32 cmg : 8;
+               u32 zeroes3;
+               u32 data[NR_MEASUREMENT_CHARS];
+       } *scmc_area;
+
+       scmc_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+       if (!scmc_area)
+               return -ENOMEM;
+
+       scmc_area->request.length = 0x0010;
+       scmc_area->request.code = 0x0022;
+
+       scmc_area->first_chpid = chp->id;
+       scmc_area->last_chpid = chp->id;
+
+       ccode = chsc(scmc_area);
+       if (ccode > 0) {
+               ret = (ccode == 3) ? -ENODEV : -EBUSY;
+               goto out;
+       }
+
+       switch (scmc_area->response.code) {
+       case 0x0001: /* Success. */
+               if (!scmc_area->not_valid) {
+                       chp->cmg = scmc_area->cmg;
+                       chp->shared = scmc_area->shared;
+                       chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
+                                                 (struct cmg_chars *)
+                                                 &scmc_area->data);
+               } else {
+                       chp->cmg = -1;
+                       chp->shared = -1;
+               }
+               ret = 0;
+               break;
+       case 0x0003: /* Invalid block. */
+       case 0x0007: /* Invalid format. */
+       case 0x0008: /* Invalid bit combination. */
+               CIO_CRW_EVENT(2, "Error in chsc request block!\n");
+               ret = -EINVAL;
+               break;
+       case 0x0004: /* Command not provided. */
+               CIO_CRW_EVENT(2, "Model does not provide scmc\n");
+               ret = -EOPNOTSUPP;
+               break;
+       default:
+               CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
+                             scmc_area->response.code);
+               ret = -EIO;
+       }
+out:
+       free_page((unsigned long)scmc_area);
+       return ret;
+}
+
 /*
  * Entries for chpids on the system bus.
  * This replaces /proc/chpids.
@@ -990,16 +1385,15 @@ new_channel_path(int chpid)
        struct channel_path *chp;
        int ret;
 
-       chp = kmalloc(sizeof(struct channel_path), GFP_KERNEL);
+       chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
        if (!chp)
                return -ENOMEM;
-       memset(chp, 0, sizeof(struct channel_path));
 
        /* fill in status, etc. */
        chp->id = chpid;
        chp->state = 1;
        chp->dev = (struct device) {
-               .parent  = &css_bus_device,
+               .parent  = &css[0]->device,
                .release = chp_release,
        };
        snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp0.%x", chpid);
@@ -1008,6 +1402,22 @@ new_channel_path(int chpid)
        ret = chsc_determine_channel_path_description(chpid, &chp->desc);
        if (ret)
                goto out_free;
+       /* Get channel-measurement characteristics. */
+       if (css_characteristics_avail && css_chsc_characteristics.scmc
+           && css_chsc_characteristics.secm) {
+               ret = chsc_get_channel_measurement_chars(chp);
+               if (ret)
+                       goto out_free;
+       } else {
+               static int msg_done;
+
+               if (!msg_done) {
+                       printk(KERN_WARNING "cio: Channel measurements not "
+                              "available, continuing.\n");
+                       msg_done = 1;
+               }
+               chp->cmg = -1;
+       }
 
        /* make it known to the system */
        ret = device_register(&chp->dev);
@@ -1020,8 +1430,19 @@ new_channel_path(int chpid)
        if (ret) {
                device_unregister(&chp->dev);
                goto out_free;
-       } else
-               chps[chpid] = chp;
+       }
+       mutex_lock(&css[0]->mutex);
+       if (css[0]->cm_enabled) {
+               ret = chsc_add_chp_cmg_attr(chp);
+               if (ret) {
+                       sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
+                       device_unregister(&chp->dev);
+                       mutex_unlock(&css[0]->mutex);
+                       goto out_free;
+               }
+       }
+       css[0]->chps[chpid] = chp;
+       mutex_unlock(&css[0]->mutex);
        return ret;
 out_free:
        kfree(chp);
@@ -1034,7 +1455,7 @@ chsc_get_chp_desc(struct subchannel *sch, int chp_no)
        struct channel_path *chp;
        struct channel_path_desc *desc;
 
-       chp = chps[sch->schib.pmcw.chpid[chp_no]];
+       chp = css[0]->chps[sch->schib.pmcw.chpid[chp_no]];
        if (!chp)
                return NULL;
        desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
@@ -1055,6 +1476,57 @@ chsc_alloc_sei_area(void)
        return (sei_page ? 0 : -ENOMEM);
 }
 
+int __init
+chsc_enable_facility(int operation_code)
+{
+       int ret;
+       struct {
+               struct chsc_header request;
+               u8 reserved1:4;
+               u8 format:4;
+               u8 reserved2;
+               u16 operation_code;
+               u32 reserved3;
+               u32 reserved4;
+               u32 operation_data_area[252];
+               struct chsc_header response;
+               u32 reserved5:4;
+               u32 format2:4;
+               u32 reserved6:24;
+       } *sda_area;
+
+       sda_area = (void *)get_zeroed_page(GFP_KERNEL|GFP_DMA);
+       if (!sda_area)
+               return -ENOMEM;
+       sda_area->request.length = 0x0400;
+       sda_area->request.code = 0x0031;
+       sda_area->operation_code = operation_code;
+
+       ret = chsc(sda_area);
+       if (ret > 0) {
+               ret = (ret == 3) ? -ENODEV : -EBUSY;
+               goto out;
+       }
+       switch (sda_area->response.code) {
+       case 0x0001: /* everything ok */
+               ret = 0;
+               break;
+       case 0x0003: /* invalid request block */
+       case 0x0007:
+               ret = -EINVAL;
+               break;
+       case 0x0004: /* command not provided */
+       case 0x0101: /* facility not provided */
+               ret = -EOPNOTSUPP;
+               break;
+       default: /* something went wrong */
+               ret = -EIO;
+       }
+ out:
+       free_page((unsigned long)sda_area);
+       return ret;
+}
+
 subsys_initcall(chsc_alloc_sei_area);
 
 struct css_general_char css_general_characteristics;
@@ -1082,10 +1554,8 @@ chsc_determine_css_characteristics(void)
                return -ENOMEM;
        }
 
-       scsc_area->request = (struct chsc_header) {
-               .length = 0x0010,
-               .code   = 0x0010,
-       };
+       scsc_area->request.length = 0x0010;
+       scsc_area->request.code = 0x0010;
 
        result = chsc(scsc_area);
        if (result) {