[S390] cio: Add chsc subchannel driver.

This patch adds a driver for subchannels of type chsc.

A device /dev/chsc is created which may be used to issue ioctls to:
- obtain information about the machine's I/O configuration
- dynamically change the machine's I/O configuration via
  asynchronous chsc commands

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

14 files changed, 906 insertions, 48 deletions

diff --git a/drivers/s390/cio/Makefile b/drivers/s390/cio/Makefile
index 6735ebb3c988..91e9e3f3073a 100644
--- a/drivers/s390/cio/Makefile
+++ b/drivers/s390/cio/Makefile
@@ -7,5 +7,6 @@ obj-y += airq.o blacklist.o chsc.o cio.o css.o chp.o idset.o isc.o scsw.o \
 ccw_device-objs += device.o device_fsm.o device_ops.o
 ccw_device-objs += device_id.o device_pgid.o device_status.o
 obj-y += ccw_device.o cmf.o
+obj-$(CONFIG_CHSC_SCH) += chsc_sch.o
 obj-$(CONFIG_CCWGROUP) += ccwgroup.o
 obj-$(CONFIG_QDIO) += qdio.o
diff --git a/drivers/s390/cio/chp.c b/drivers/s390/cio/chp.c
index e40eda0ed462..8644c80a2056 100644
--- a/drivers/s390/cio/chp.c
+++ b/drivers/s390/cio/chp.c
@@ -407,7 +407,7 @@ int chp_new(struct chp_id chpid)
                  chpid.id);
 
         /* Obtain channel path description and fill it in. */
-        ret = chsc_determine_channel_path_description(chpid, &chp->desc);
+        ret = chsc_determine_base_channel_path_desc(chpid, &chp->desc);
         if (ret)
                 goto out_free;
         if ((chp->desc.flags & 0x80) == 0) {
diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index e23c3806972a..65264a38057d 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -15,6 +15,7 @@
 
 #include <asm/cio.h>
 #include <asm/chpid.h>
+#include <asm/chsc.h>
 
 #include "../s390mach.h"
 #include "css.h"
@@ -627,23 +628,33 @@ chsc_secm(struct channel_subsystem *css, int enable)
         return ret;
 }
 
-int chsc_determine_channel_path_description(struct chp_id chpid,
-                                            struct channel_path_desc *desc)
+int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,
+                                     int c, int m,
+                                     struct chsc_response_struct *resp)
 {
         int ccode, ret;
 
         struct {
                 struct chsc_header request;
-                u32 : 24;
+                u32 : 2;
+                u32 m : 1;
+                u32 c : 1;
+                u32 fmt : 4;
+                u32 cssid : 8;
+                u32 : 4;
+                u32 rfmt : 4;
                 u32 first_chpid : 8;
                 u32 : 24;
                 u32 last_chpid : 8;
                 u32 zeroes1;
                 struct chsc_header response;
-                u32 zeroes2;
-                struct channel_path_desc desc;
+                u8 data[PAGE_SIZE - 20];
         } __attribute__ ((packed)) *scpd_area;
 
+        if ((rfmt == 1) && !css_general_characteristics.fcs)
+                return -EINVAL;
+        if ((rfmt == 2) && !css_general_characteristics.cib)
+                return -EINVAL;
         scpd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
         if (!scpd_area)
                 return -ENOMEM;
@@ -651,8 +662,13 @@ int chsc_determine_channel_path_description(struct chp_id chpid,
         scpd_area->request.length = 0x0010;
         scpd_area->request.code = 0x0002;
 
+        scpd_area->cssid = chpid.cssid;
         scpd_area->first_chpid = chpid.id;
         scpd_area->last_chpid = chpid.id;
+        scpd_area->m = m;
+        scpd_area->c = c;
+        scpd_area->fmt = fmt;
+        scpd_area->rfmt = rfmt;
 
         ccode = chsc(scpd_area);
         if (ccode > 0) {
@@ -663,8 +679,7 @@ int chsc_determine_channel_path_description(struct chp_id chpid,
         ret = chsc_error_from_response(scpd_area->response.code);
         if (ret == 0)
                 /* Success. */
-                memcpy(desc, &scpd_area->desc,
-                       sizeof(struct channel_path_desc));
+                memcpy(resp, &scpd_area->response, scpd_area->response.length);
         else
                 CIO_CRW_EVENT(2, "chsc: scpd failed (rc=%04x)\n",
                               scpd_area->response.code);
@@ -672,6 +687,25 @@ out:
         free_page((unsigned long)scpd_area);
         return ret;
 }
+EXPORT_SYMBOL_GPL(chsc_determine_channel_path_desc);
+
+int chsc_determine_base_channel_path_desc(struct chp_id chpid,
+                                          struct channel_path_desc *desc)
+{
+        struct chsc_response_struct *chsc_resp;
+        int ret;
+
+        chsc_resp = kzalloc(sizeof(*chsc_resp), GFP_KERNEL);
+        if (!chsc_resp)
+                return -ENOMEM;
+        ret = chsc_determine_channel_path_desc(chpid, 0, 0, 0, 0, chsc_resp);
+        if (ret)
+                goto out_free;
+        memcpy(desc, &chsc_resp->data, chsc_resp->length);
+out_free:
+        kfree(chsc_resp);
+        return ret;
+}
 
 static void
 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
diff --git a/drivers/s390/cio/chsc.h b/drivers/s390/cio/chsc.h
index 2a38b5090228..fb6c4d6c45b4 100644
--- a/drivers/s390/cio/chsc.h
+++ b/drivers/s390/cio/chsc.h
@@ -4,7 +4,8 @@
 #include <linux/types.h>
 #include <linux/device.h>
 #include <asm/chpid.h>
-#include "schid.h"
+#include <asm/chsc.h>
+#include <asm/schid.h>
 
 #define CHSC_SDA_OC_MSS   0x2
 
@@ -37,11 +38,14 @@ struct channel_path_desc {
 struct channel_path;
 
 struct css_general_char {
-        u64 : 41;
+        u64 : 12;
+        u32 dynio : 1;   /* bit 12 */
+        u32 : 28;
         u32 aif : 1;     /* bit 41 */
         u32 : 3;
         u32 mcss : 1;    /* bit 45 */
-        u32 : 2;
+        u32 fcs : 1;     /* bit 46 */
+        u32 : 1;
         u32 ext_mb : 1;  /* bit 48 */
         u32 : 7;
         u32 aif_tdd : 1; /* bit 56 */
@@ -49,7 +53,9 @@ struct css_general_char {
         u32 qebsm : 1;   /* bit 58 */
         u32 : 8;
         u32 aif_osa : 1; /* bit 67 */
-        u32 : 20;
+        u32 : 14;
+        u32 cib : 1;     /* bit 82 */
+        u32 : 5;
         u32 fcx : 1;     /* bit 88 */
         u32 : 7;
 }__attribute__((packed));
@@ -86,8 +92,11 @@ struct channel_subsystem;
 extern int chsc_secm(struct channel_subsystem *, int);
 
 int chsc_chp_vary(struct chp_id chpid, int on);
-int chsc_determine_channel_path_description(struct chp_id chpid,
-                                            struct channel_path_desc *desc);
+int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,
+                                     int c, int m,
+                                     struct chsc_response_struct *resp);
+int chsc_determine_base_channel_path_desc(struct chp_id chpid,
+                                          struct channel_path_desc *desc);
 void chsc_chp_online(struct chp_id chpid);
 void chsc_chp_offline(struct chp_id chpid);
 int chsc_get_channel_measurement_chars(struct channel_path *chp);
diff --git a/drivers/s390/cio/chsc_sch.c b/drivers/s390/cio/chsc_sch.c
new file mode 100644
index 000000000000..91ca87aa9f97
--- /dev/null
+++ b/drivers/s390/cio/chsc_sch.c
@@ -0,0 +1,820 @@
+/*
+ * Driver for s390 chsc subchannels
+ *
+ * Copyright IBM Corp. 2008
+ * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/miscdevice.h>
+
+#include <asm/cio.h>
+#include <asm/chsc.h>
+#include <asm/isc.h>
+
+#include "cio.h"
+#include "cio_debug.h"
+#include "css.h"
+#include "chsc_sch.h"
+#include "ioasm.h"
+
+static debug_info_t *chsc_debug_msg_id;
+static debug_info_t *chsc_debug_log_id;
+
+#define CHSC_MSG(imp, args...) do {                                     \
+                debug_sprintf_event(chsc_debug_msg_id, imp , ##args);   \
+        } while (0)
+
+#define CHSC_LOG(imp, txt) do {                                 \
+                debug_text_event(chsc_debug_log_id, imp , txt); \
+        } while (0)
+
+static void CHSC_LOG_HEX(int level, void *data, int length)
+{
+        while (length > 0) {
+                debug_event(chsc_debug_log_id, level, data, length);
+                length -= chsc_debug_log_id->buf_size;
+                data += chsc_debug_log_id->buf_size;
+        }
+}
+
+MODULE_AUTHOR("IBM Corporation");
+MODULE_DESCRIPTION("driver for s390 chsc subchannels");
+MODULE_LICENSE("GPL");
+
+static void chsc_subchannel_irq(struct subchannel *sch)
+{
+        struct chsc_private *private = sch->private;
+        struct chsc_request *request = private->request;
+        struct irb *irb = (struct irb *)__LC_IRB;
+
+        CHSC_LOG(4, "irb");
+        CHSC_LOG_HEX(4, irb, sizeof(*irb));
+        /* Copy irb to provided request and set done. */
+        if (!request) {
+                CHSC_MSG(0, "Interrupt on sch 0.%x.%04x with no request\n",
+                         sch->schid.ssid, sch->schid.sch_no);
+                return;
+        }
+        private->request = NULL;
+        memcpy(&request->irb, irb, sizeof(*irb));
+        stsch(sch->schid, &sch->schib);
+        complete(&request->completion);
+        put_device(&sch->dev);
+}
+
+static int chsc_subchannel_probe(struct subchannel *sch)
+{
+        struct chsc_private *private;
+        int ret;
+
+        CHSC_MSG(6, "Detected chsc subchannel 0.%x.%04x\n",
+                 sch->schid.ssid, sch->schid.sch_no);
+        sch->isc = CHSC_SCH_ISC;
+        private = kzalloc(sizeof(*private), GFP_KERNEL);
+        if (!private)
+                return -ENOMEM;
+        ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch);
+        if (ret) {
+                CHSC_MSG(0, "Failed to enable 0.%x.%04x: %d\n",
+                         sch->schid.ssid, sch->schid.sch_no, ret);
+                kfree(private);
+        } else {
+                sch->private = private;
+                if (sch->dev.uevent_suppress) {
+                        sch->dev.uevent_suppress = 0;
+                        kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
+                }
+        }
+        return ret;
+}
+
+static int chsc_subchannel_remove(struct subchannel *sch)
+{
+        struct chsc_private *private;
+
+        cio_disable_subchannel(sch);
+        private = sch->private;
+        sch->private = NULL;
+        if (private->request) {
+                complete(&private->request->completion);
+                put_device(&sch->dev);
+        }
+        kfree(private);
+        return 0;
+}
+
+static void chsc_subchannel_shutdown(struct subchannel *sch)
+{
+        cio_disable_subchannel(sch);
+}
+
+static struct css_device_id chsc_subchannel_ids[] = {
+        { .match_flags = 0x1, .type =SUBCHANNEL_TYPE_CHSC, },
+        { /* end of list */ },
+};
+MODULE_DEVICE_TABLE(css, chsc_subchannel_ids);
+
+static struct css_driver chsc_subchannel_driver = {
+        .owner = THIS_MODULE,
+        .subchannel_type = chsc_subchannel_ids,
+        .irq = chsc_subchannel_irq,
+        .probe = chsc_subchannel_probe,
+        .remove = chsc_subchannel_remove,
+        .shutdown = chsc_subchannel_shutdown,
+        .name = "chsc_subchannel",
+};
+
+static int __init chsc_init_dbfs(void)
+{
+        chsc_debug_msg_id = debug_register("chsc_msg", 16, 1,
+                                           16 * sizeof(long));
+        if (!chsc_debug_msg_id)
+                goto out;
+        debug_register_view(chsc_debug_msg_id, &debug_sprintf_view);
+        debug_set_level(chsc_debug_msg_id, 2);
+        chsc_debug_log_id = debug_register("chsc_log", 16, 1, 16);
+        if (!chsc_debug_log_id)
+                goto out;
+        debug_register_view(chsc_debug_log_id, &debug_hex_ascii_view);
+        debug_set_level(chsc_debug_log_id, 2);
+        return 0;
+out:
+        if (chsc_debug_msg_id)
+                debug_unregister(chsc_debug_msg_id);
+        return -ENOMEM;
+}
+
+static void chsc_remove_dbfs(void)
+{
+        debug_unregister(chsc_debug_log_id);
+        debug_unregister(chsc_debug_msg_id);
+}
+
+static int __init chsc_init_sch_driver(void)
+{
+        return css_driver_register(&chsc_subchannel_driver);
+}
+
+static void chsc_cleanup_sch_driver(void)
+{
+        css_driver_unregister(&chsc_subchannel_driver);
+}
+
+static DEFINE_SPINLOCK(chsc_lock);
+
+static int chsc_subchannel_match_next_free(struct device *dev, void *data)
+{
+        struct subchannel *sch = to_subchannel(dev);
+
+        return sch->schib.pmcw.ena && !scsw_fctl(&sch->schib.scsw);
+}
+
+static struct subchannel *chsc_get_next_subchannel(struct subchannel *sch)
+{
+        struct device *dev;
+
+        dev = driver_find_device(&chsc_subchannel_driver.drv,
+                                 sch ? &sch->dev : NULL, NULL,
+                                 chsc_subchannel_match_next_free);
+        return dev ? to_subchannel(dev) : NULL;
+}
+
+/**
+ * chsc_async() - try to start a chsc request asynchronously
+ * @chsc_area: request to be started
+ * @request: request structure to associate
+ *
+ * Tries to start a chsc request on one of the existing chsc subchannels.
+ * Returns:
+ *  %0 if the request was performed synchronously
+ *  %-EINPROGRESS if the request was successfully started
+ *  %-EBUSY if all chsc subchannels are busy
+ *  %-ENODEV if no chsc subchannels are available
+ * Context:
+ *  interrupts disabled, chsc_lock held
+ */
+static int chsc_async(struct chsc_async_area *chsc_area,
+                      struct chsc_request *request)
+{
+        int cc;
+        struct chsc_private *private;
+        struct subchannel *sch = NULL;
+        int ret = -ENODEV;
+        char dbf[10];
+
+        chsc_area->header.key = PAGE_DEFAULT_KEY;
+        while ((sch = chsc_get_next_subchannel(sch))) {
+                spin_lock(sch->lock);
+                private = sch->private;
+                if (private->request) {
+                        spin_unlock(sch->lock);
+                        ret = -EBUSY;
+                        continue;
+                }
+                chsc_area->header.sid = sch->schid;
+                CHSC_LOG(2, "schid");
+                CHSC_LOG_HEX(2, &sch->schid, sizeof(sch->schid));
+                cc = chsc(chsc_area);
+                sprintf(dbf, "cc:%d", cc);
+                CHSC_LOG(2, dbf);
+                switch (cc) {
+                case 0:
+                        ret = 0;
+                        break;
+                case 1:
+                        sch->schib.scsw.cmd.fctl |= SCSW_FCTL_START_FUNC;
+                        ret = -EINPROGRESS;
+                        private->request = request;
+                        break;
+                case 2:
+                        ret = -EBUSY;
+                        break;
+                default:
+                        ret = -ENODEV;
+                }
+                spin_unlock(sch->lock);
+                CHSC_MSG(2, "chsc on 0.%x.%04x returned cc=%d\n",
+                         sch->schid.ssid, sch->schid.sch_no, cc);
+                if (ret == -EINPROGRESS)
+                        return -EINPROGRESS;
+                put_device(&sch->dev);
+                if (ret == 0)
+                        return 0;
+        }
+        return ret;
+}
+
+static void chsc_log_command(struct chsc_async_area *chsc_area)
+{
+        char dbf[10];
+
+        sprintf(dbf, "CHSC:%x", chsc_area->header.code);
+        CHSC_LOG(0, dbf);
+        CHSC_LOG_HEX(0, chsc_area, 32);
+}
+
+static int chsc_examine_irb(struct chsc_request *request)
+{
+        int backed_up;
+
+        if (!scsw_stctl(&request->irb.scsw) & SCSW_STCTL_STATUS_PEND)
+                return -EIO;
+        backed_up = scsw_cstat(&request->irb.scsw) & SCHN_STAT_CHAIN_CHECK;
+        request->irb.scsw.cmd.cstat &= ~SCHN_STAT_CHAIN_CHECK;
+        if (scsw_cstat(&request->irb.scsw) == 0)
+                return 0;
+        if (!backed_up)
+                return 0;
+        if (scsw_cstat(&request->irb.scsw) & SCHN_STAT_PROG_CHECK)
+                return -EIO;
+        if (scsw_cstat(&request->irb.scsw) & SCHN_STAT_PROT_CHECK)
+                return -EPERM;
+        if (scsw_cstat(&request->irb.scsw) & SCHN_STAT_CHN_DATA_CHK)
+                return -EAGAIN;
+        if (scsw_cstat(&request->irb.scsw) & SCHN_STAT_CHN_CTRL_CHK)
+                return -EAGAIN;
+        return -EIO;
+}
+
+static int chsc_ioctl_start(void __user *user_area)
+{
+        struct chsc_request *request;
+        struct chsc_async_area *chsc_area;
+        int ret;
+        char dbf[10];
+
+        if (!css_general_characteristics.dynio)
+                /* It makes no sense to try. */
+                return -EOPNOTSUPP;
+        chsc_area = (void *)get_zeroed_page(GFP_DMA | GFP_KERNEL);
+        if (!chsc_area)
+                return -ENOMEM;
+        request = kzalloc(sizeof(*request), GFP_KERNEL);
+        if (!request) {
+                ret = -ENOMEM;
+                goto out_free;
+        }
+        init_completion(&request->completion);
+        if (copy_from_user(chsc_area, user_area, PAGE_SIZE)) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        chsc_log_command(chsc_area);
+        spin_lock_irq(&chsc_lock);
+        ret = chsc_async(chsc_area, request);
+        spin_unlock_irq(&chsc_lock);
+        if (ret == -EINPROGRESS) {
+                wait_for_completion(&request->completion);
+                ret = chsc_examine_irb(request);
+        }
+        /* copy area back to user */
+        if (!ret)
+                if (copy_to_user(user_area, chsc_area, PAGE_SIZE))
+                        ret = -EFAULT;
+out_free:
+        sprintf(dbf, "ret:%d", ret);
+        CHSC_LOG(0, dbf);
+        kfree(request);
+        free_page((unsigned long)chsc_area);
+        return ret;
+}
+
+static int chsc_ioctl_info_channel_path(void __user *user_cd)
+{
+        struct chsc_chp_cd *cd;
+        int ret, ccode;
+        struct {
+                struct chsc_header request;
+                u32 : 2;
+                u32 m : 1;
+                u32 : 1;
+                u32 fmt1 : 4;
+                u32 cssid : 8;
+                u32 : 8;
+                u32 first_chpid : 8;
+                u32 : 24;
+                u32 last_chpid : 8;
+                u32 : 32;
+                struct chsc_header response;
+                u8 data[PAGE_SIZE - 20];
+        } __attribute__ ((packed)) *scpcd_area;
+
+        scpcd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+        if (!scpcd_area)
+                return -ENOMEM;
+        cd = kzalloc(sizeof(*cd), GFP_KERNEL);
+        if (!cd) {
+                ret = -ENOMEM;
+                goto out_free;
+        }
+        if (copy_from_user(cd, user_cd, sizeof(*cd))) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        scpcd_area->request.length = 0x0010;
+        scpcd_area->request.code = 0x0028;
+        scpcd_area->m = cd->m;
+        scpcd_area->fmt1 = cd->fmt;
+        scpcd_area->cssid = cd->chpid.cssid;
+        scpcd_area->first_chpid = cd->chpid.id;
+        scpcd_area->last_chpid = cd->chpid.id;
+
+        ccode = chsc(scpcd_area);
+        if (ccode != 0) {
+                ret = -EIO;
+                goto out_free;
+        }
+        if (scpcd_area->response.code != 0x0001) {
+                ret = -EIO;
+                CHSC_MSG(0, "scpcd: response code=%x\n",
+                         scpcd_area->response.code);
+                goto out_free;
+        }
+        memcpy(&cd->cpcb, &scpcd_area->response, scpcd_area->response.length);
+        if (copy_to_user(user_cd, cd, sizeof(*cd)))
+                ret = -EFAULT;
+        else
+                ret = 0;
+out_free:
+        kfree(cd);
+        free_page((unsigned long)scpcd_area);
+        return ret;
+}
+
+static int chsc_ioctl_info_cu(void __user *user_cd)
+{
+        struct chsc_cu_cd *cd;
+        int ret, ccode;
+        struct {
+                struct chsc_header request;
+                u32 : 2;
+                u32 m : 1;
+                u32 : 1;
+                u32 fmt1 : 4;
+                u32 cssid : 8;
+                u32 : 8;
+                u32 first_cun : 8;
+                u32 : 24;
+                u32 last_cun : 8;
+                u32 : 32;
+                struct chsc_header response;
+                u8 data[PAGE_SIZE - 20];
+        } __attribute__ ((packed)) *scucd_area;
+
+        scucd_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+        if (!scucd_area)
+                return -ENOMEM;
+        cd = kzalloc(sizeof(*cd), GFP_KERNEL);
+        if (!cd) {
+                ret = -ENOMEM;
+                goto out_free;
+        }
+        if (copy_from_user(cd, user_cd, sizeof(*cd))) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        scucd_area->request.length = 0x0010;
+        scucd_area->request.code = 0x0028;
+        scucd_area->m = cd->m;
+        scucd_area->fmt1 = cd->fmt;
+        scucd_area->cssid = cd->cssid;
+        scucd_area->first_cun = cd->cun;
+        scucd_area->last_cun = cd->cun;
+
+        ccode = chsc(scucd_area);
+        if (ccode != 0) {
+                ret = -EIO;
+                goto out_free;
+        }
+        if (scucd_area->response.code != 0x0001) {
+                ret = -EIO;
+                CHSC_MSG(0, "scucd: response code=%x\n",
+                         scucd_area->response.code);
+                goto out_free;
+        }
+        memcpy(&cd->cucb, &scucd_area->response, scucd_area->response.length);
+        if (copy_to_user(user_cd, cd, sizeof(*cd)))
+                ret = -EFAULT;
+        else
+                ret = 0;
+out_free:
+        kfree(cd);
+        free_page((unsigned long)scucd_area);
+        return ret;
+}
+
+static int chsc_ioctl_info_sch_cu(void __user *user_cud)
+{
+        struct chsc_sch_cud *cud;
+        int ret, ccode;
+        struct {
+                struct chsc_header request;
+                u32 : 2;
+                u32 m : 1;
+                u32 : 5;
+                u32 fmt1 : 4;
+                u32 : 2;
+                u32 ssid : 2;
+                u32 first_sch : 16;
+                u32 : 8;
+                u32 cssid : 8;
+                u32 last_sch : 16;
+                u32 : 32;
+                struct chsc_header response;
+                u8 data[PAGE_SIZE - 20];
+        } __attribute__ ((packed)) *sscud_area;
+
+        sscud_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+        if (!sscud_area)
+                return -ENOMEM;
+        cud = kzalloc(sizeof(*cud), GFP_KERNEL);
+        if (!cud) {
+                ret = -ENOMEM;
+                goto out_free;
+        }
+        if (copy_from_user(cud, user_cud, sizeof(*cud))) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        sscud_area->request.length = 0x0010;
+        sscud_area->request.code = 0x0006;
+        sscud_area->m = cud->schid.m;
+        sscud_area->fmt1 = cud->fmt;
+        sscud_area->ssid = cud->schid.ssid;
+        sscud_area->first_sch = cud->schid.sch_no;
+        sscud_area->cssid = cud->schid.cssid;
+        sscud_area->last_sch = cud->schid.sch_no;
+
+        ccode = chsc(sscud_area);
+        if (ccode != 0) {
+                ret = -EIO;
+                goto out_free;
+        }
+        if (sscud_area->response.code != 0x0001) {
+                ret = -EIO;
+                CHSC_MSG(0, "sscud: response code=%x\n",
+                         sscud_area->response.code);
+                goto out_free;
+        }
+        memcpy(&cud->scub, &sscud_area->response, sscud_area->response.length);
+        if (copy_to_user(user_cud, cud, sizeof(*cud)))
+                ret = -EFAULT;
+        else
+                ret = 0;
+out_free:
+        kfree(cud);
+        free_page((unsigned long)sscud_area);
+        return ret;
+}
+
+static int chsc_ioctl_conf_info(void __user *user_ci)
+{
+        struct chsc_conf_info *ci;
+        int ret, ccode;
+        struct {
+                struct chsc_header request;
+                u32 : 2;
+                u32 m : 1;
+                u32 : 1;
+                u32 fmt1 : 4;
+                u32 cssid : 8;
+                u32 : 6;
+                u32 ssid : 2;
+                u32 : 8;
+                u64 : 64;
+                struct chsc_header response;
+                u8 data[PAGE_SIZE - 20];
+        } __attribute__ ((packed)) *sci_area;
+
+        sci_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+        if (!sci_area)
+                return -ENOMEM;
+        ci = kzalloc(sizeof(*ci), GFP_KERNEL);
+        if (!ci) {
+                ret = -ENOMEM;
+                goto out_free;
+        }
+        if (copy_from_user(ci, user_ci, sizeof(*ci))) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        sci_area->request.length = 0x0010;
+        sci_area->request.code = 0x0012;
+        sci_area->m = ci->id.m;
+        sci_area->fmt1 = ci->fmt;
+        sci_area->cssid = ci->id.cssid;
+        sci_area->ssid = ci->id.ssid;
+
+        ccode = chsc(sci_area);
+        if (ccode != 0) {
+                ret = -EIO;
+                goto out_free;
+        }
+        if (sci_area->response.code != 0x0001) {
+                ret = -EIO;
+                CHSC_MSG(0, "sci: response code=%x\n",
+                         sci_area->response.code);
+                goto out_free;
+        }
+        memcpy(&ci->scid, &sci_area->response, sci_area->response.length);
+        if (copy_to_user(user_ci, ci, sizeof(*ci)))
+                ret = -EFAULT;
+        else
+                ret = 0;
+out_free:
+        kfree(ci);
+        free_page((unsigned long)sci_area);
+        return ret;
+}
+
+static int chsc_ioctl_conf_comp_list(void __user *user_ccl)
+{
+        struct chsc_comp_list *ccl;
+        int ret, ccode;
+        struct {
+                struct chsc_header request;
+                u32 ctype : 8;
+                u32 : 4;
+                u32 fmt : 4;
+                u32 : 16;
+                u64 : 64;
+                u32 list_parm[2];
+                u64 : 64;
+                struct chsc_header response;
+                u8 data[PAGE_SIZE - 36];
+        } __attribute__ ((packed)) *sccl_area;
+        struct {
+                u32 m : 1;
+                u32 : 31;
+                u32 cssid : 8;
+                u32 : 16;
+                u32 chpid : 8;
+        } __attribute__ ((packed)) *chpid_parm;
+        struct {
+                u32 f_cssid : 8;
+                u32 l_cssid : 8;
+                u32 : 16;
+                u32 res;
+        } __attribute__ ((packed)) *cssids_parm;
+
+        sccl_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+        if (!sccl_area)
+                return -ENOMEM;
+        ccl = kzalloc(sizeof(*ccl), GFP_KERNEL);
+        if (!ccl) {
+                ret = -ENOMEM;
+                goto out_free;
+        }
+        if (copy_from_user(ccl, user_ccl, sizeof(*ccl))) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        sccl_area->request.length = 0x0020;
+        sccl_area->request.code = 0x0030;
+        sccl_area->fmt = ccl->req.fmt;
+        sccl_area->ctype = ccl->req.ctype;
+        switch (sccl_area->ctype) {
+        case CCL_CU_ON_CHP:
+        case CCL_IOP_CHP:
+                chpid_parm = (void *)&sccl_area->list_parm;
+                chpid_parm->m = ccl->req.chpid.m;
+                chpid_parm->cssid = ccl->req.chpid.chp.cssid;
+                chpid_parm->chpid = ccl->req.chpid.chp.id;
+                break;
+        case CCL_CSS_IMG:
+        case CCL_CSS_IMG_CONF_CHAR:
+                cssids_parm = (void *)&sccl_area->list_parm;
+                cssids_parm->f_cssid = ccl->req.cssids.f_cssid;
+                cssids_parm->l_cssid = ccl->req.cssids.l_cssid;
+                break;
+        }
+        ccode = chsc(sccl_area);
+        if (ccode != 0) {
+                ret = -EIO;
+                goto out_free;
+        }
+        if (sccl_area->response.code != 0x0001) {
+                ret = -EIO;
+                CHSC_MSG(0, "sccl: response code=%x\n",
+                         sccl_area->response.code);
+                goto out_free;
+        }
+        memcpy(&ccl->sccl, &sccl_area->response, sccl_area->response.length);
+        if (copy_to_user(user_ccl, ccl, sizeof(*ccl)))
+                ret = -EFAULT;
+        else
+                ret = 0;
+out_free:
+        kfree(ccl);
+        free_page((unsigned long)sccl_area);
+        return ret;
+}
+
+static int chsc_ioctl_chpd(void __user *user_chpd)
+{
+        struct chsc_cpd_info *chpd;
+        int ret;
+
+        chpd = kzalloc(sizeof(*chpd), GFP_KERNEL);
+        if (!chpd)
+                return -ENOMEM;
+        if (copy_from_user(chpd, user_chpd, sizeof(*chpd))) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        ret = chsc_determine_channel_path_desc(chpd->chpid, chpd->fmt,
+                                               chpd->rfmt, chpd->c, chpd->m,
+                                               &chpd->chpdb);
+        if (ret)
+                goto out_free;
+        if (copy_to_user(user_chpd, chpd, sizeof(*chpd)))
+                ret = -EFAULT;
+out_free:
+        kfree(chpd);
+        return ret;
+}
+
+static int chsc_ioctl_dcal(void __user *user_dcal)
+{
+        struct chsc_dcal *dcal;
+        int ret, ccode;
+        struct {
+                struct chsc_header request;
+                u32 atype : 8;
+                u32 : 4;
+                u32 fmt : 4;
+                u32 : 16;
+                u32 res0[2];
+                u32 list_parm[2];
+                u32 res1[2];
+                struct chsc_header response;
+                u8 data[PAGE_SIZE - 36];
+        } __attribute__ ((packed)) *sdcal_area;
+
+        sdcal_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+        if (!sdcal_area)
+                return -ENOMEM;
+        dcal = kzalloc(sizeof(*dcal), GFP_KERNEL);
+        if (!dcal) {
+                ret = -ENOMEM;
+                goto out_free;
+        }
+        if (copy_from_user(dcal, user_dcal, sizeof(*dcal))) {
+                ret = -EFAULT;
+                goto out_free;
+        }
+        sdcal_area->request.length = 0x0020;
+        sdcal_area->request.code = 0x0034;
+        sdcal_area->atype = dcal->req.atype;
+        sdcal_area->fmt = dcal->req.fmt;
+        memcpy(&sdcal_area->list_parm, &dcal->req.list_parm,
+               sizeof(sdcal_area->list_parm));
+
+        ccode = chsc(sdcal_area);
+        if (ccode != 0) {
+                ret = -EIO;
+                goto out_free;
+        }
+        if (sdcal_area->response.code != 0x0001) {
+                ret = -EIO;
+                CHSC_MSG(0, "sdcal: response code=%x\n",
+                         sdcal_area->response.code);
+                goto out_free;
+        }
+        memcpy(&dcal->sdcal, &sdcal_area->response,
+               sdcal_area->response.length);
+        if (copy_to_user(user_dcal, dcal, sizeof(*dcal)))
+                ret = -EFAULT;
+        else
+                ret = 0;
+out_free:
+        kfree(dcal);
+        free_page((unsigned long)sdcal_area);
+        return ret;
+}
+
+static long chsc_ioctl(struct file *filp, unsigned int cmd,
+                       unsigned long arg)
+{
+        CHSC_MSG(2, "chsc_ioctl called, cmd=%x\n", cmd);
+        switch (cmd) {
+        case CHSC_START:
+                return chsc_ioctl_start((void __user *)arg);
+        case CHSC_INFO_CHANNEL_PATH:
+                return chsc_ioctl_info_channel_path((void __user *)arg);
+        case CHSC_INFO_CU:
+                return chsc_ioctl_info_cu((void __user *)arg);
+        case CHSC_INFO_SCH_CU:
+                return chsc_ioctl_info_sch_cu((void __user *)arg);
+        case CHSC_INFO_CI:
+                return chsc_ioctl_conf_info((void __user *)arg);
+        case CHSC_INFO_CCL:
+                return chsc_ioctl_conf_comp_list((void __user *)arg);
+        case CHSC_INFO_CPD:
+                return chsc_ioctl_chpd((void __user *)arg);
+        case CHSC_INFO_DCAL:
+                return chsc_ioctl_dcal((void __user *)arg);
+        default: /* unknown ioctl number */
+                return -ENOIOCTLCMD;
+        }
+}
+
+static const struct file_operations chsc_fops = {
+        .owner = THIS_MODULE,
+        .unlocked_ioctl = chsc_ioctl,
+        .compat_ioctl = chsc_ioctl,
+};
+
+static struct miscdevice chsc_misc_device = {
+        .minor = MISC_DYNAMIC_MINOR,
+        .name = "chsc",
+        .fops = &chsc_fops,
+};
+
+static int __init chsc_misc_init(void)
+{
+        return misc_register(&chsc_misc_device);
+}
+
+static void chsc_misc_cleanup(void)
+{
+        misc_deregister(&chsc_misc_device);
+}
+
+static int __init chsc_sch_init(void)
+{
+        int ret;
+
+        ret = chsc_init_dbfs();
+        if (ret)
+                return ret;
+        isc_register(CHSC_SCH_ISC);
+        ret = chsc_init_sch_driver();
+        if (ret)
+                goto out_dbf;
+        ret = chsc_misc_init();
+        if (ret)
+                goto out_driver;
+        return ret;
+out_driver:
+        chsc_cleanup_sch_driver();
+out_dbf:
+        isc_unregister(CHSC_SCH_ISC);
+        chsc_remove_dbfs();
+        return ret;
+}
+
+static void __exit chsc_sch_exit(void)
+{
+        chsc_misc_cleanup();
+        chsc_cleanup_sch_driver();
+        isc_unregister(CHSC_SCH_ISC);
+        chsc_remove_dbfs();
+}
+
+module_init(chsc_sch_init);
+module_exit(chsc_sch_exit);
diff --git a/drivers/s390/cio/chsc_sch.h b/drivers/s390/cio/chsc_sch.h
new file mode 100644
index 000000000000..589ebfad6aad
--- /dev/null
+++ b/drivers/s390/cio/chsc_sch.h
@@ -0,0 +1,13 @@
+#ifndef _CHSC_SCH_H
+#define _CHSC_SCH_H
+
+struct chsc_request {
+        struct completion completion;
+        struct irb irb;
+};
+
+struct chsc_private {
+        struct chsc_request *request;
+};
+
+#endif
diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 34b38fb7c2f7..6ebf1b507362 100644
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -877,6 +877,12 @@ __clear_io_subchannel_easy(struct subchannel_id schid)
         return -EBUSY;
 }
 
+static void __clear_chsc_subchannel_easy(void)
+{
+        /* It seems we can only wait for a bit here :/ */
+        udelay_reset(100);
+}
+
 static int pgm_check_occured;
 
 static void cio_reset_pgm_check_handler(void)
@@ -920,6 +926,9 @@ static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data)
                         if (__clear_io_subchannel_easy(schid))
                                 goto out; /* give up... */
                         break;
+                case SUBCHANNEL_TYPE_CHSC:
+                        __clear_chsc_subchannel_easy();
+                        break;
                 default:
                         /* No default clear strategy */
                         break;
diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h
index 2e7e571d1200..3b236d20e835 100644
--- a/drivers/s390/cio/cio.h
+++ b/drivers/s390/cio/cio.h
@@ -7,8 +7,8 @@
 #include <asm/chpid.h>
 #include <asm/cio.h>
 #include <asm/fcx.h>
+#include <asm/schid.h>
 #include "chsc.h"
-#include "schid.h"
 
 /*
  * path management control word
diff --git a/drivers/s390/cio/css.h b/drivers/s390/cio/css.h
index 58020bf41ed0..57ebf120f825 100644
--- a/drivers/s390/cio/css.h
+++ b/drivers/s390/cio/css.h
@@ -9,8 +9,7 @@
 
 #include <asm/cio.h>
 #include <asm/chpid.h>
-
-#include "schid.h"
+#include <asm/schid.h>
 
 /*
  * path grouping stuff
diff --git a/drivers/s390/cio/idset.h b/drivers/s390/cio/idset.h
index 144466ab8c15..528065cb5021 100644
--- a/drivers/s390/cio/idset.h
+++ b/drivers/s390/cio/idset.h
@@ -8,7 +8,7 @@
 #ifndef S390_IDSET_H
 #define S390_IDSET_H S390_IDSET_H
 
-#include "schid.h"
+#include <asm/schid.h>
 
 struct idset;
 
diff --git a/drivers/s390/cio/io_sch.h b/drivers/s390/cio/io_sch.h
index b774960e76af..3f8f1cf69c76 100644
--- a/drivers/s390/cio/io_sch.h
+++ b/drivers/s390/cio/io_sch.h
@@ -1,7 +1,7 @@
 #ifndef S390_IO_SCH_H
 #define S390_IO_SCH_H
 
-#include "schid.h"
+#include <asm/schid.h>
 
 /*
  * command-mode operation request block
diff --git a/drivers/s390/cio/ioasm.h b/drivers/s390/cio/ioasm.h
index 652ea3625f9d..9fa2ac13ac85 100644
--- a/drivers/s390/cio/ioasm.h
+++ b/drivers/s390/cio/ioasm.h
@@ -2,7 +2,7 @@
 #define S390_CIO_IOASM_H
 
 #include <asm/chpid.h>
-#include "schid.h"
+#include <asm/schid.h>
 
 /*
  * TPI info structure
diff --git a/drivers/s390/cio/qdio.h b/drivers/s390/cio/qdio.h
index 733934a166b1..7656081a24d2 100644
--- a/drivers/s390/cio/qdio.h
+++ b/drivers/s390/cio/qdio.h
@@ -3,8 +3,7 @@
 
 #include <asm/page.h>
 #include <asm/isc.h>
-
-#include "schid.h"
+#include <asm/schid.h>
 
 #ifdef CONFIG_QDIO_DEBUG
 #define QDIO_VERBOSE_LEVEL 9
diff --git a/drivers/s390/cio/schid.h b/drivers/s390/cio/schid.h
deleted file mode 100644
index 54328fec5ade..000000000000
--- a/drivers/s390/cio/schid.h
+++ /dev/null
@@ -1,26 +0,0 @@
-#ifndef S390_SCHID_H
-#define S390_SCHID_H
-
-struct subchannel_id {
-        __u32 reserved:13;
-        __u32 ssid:2;
-        __u32 one:1;
-        __u32 sch_no:16;
-} __attribute__ ((packed,aligned(4)));
-
-
-/* Helper function for sane state of pre-allocated subchannel_id. */
-static inline void
-init_subchannel_id(struct subchannel_id *schid)
-{
-        memset(schid, 0, sizeof(struct subchannel_id));
-        schid->one = 1;
-}
-
-static inline int
-schid_equal(struct subchannel_id *schid1, struct subchannel_id *schid2)
-{
-        return !memcmp(schid1, schid2, sizeof(struct subchannel_id));
-}
-
-#endif /* S390_SCHID_H */