[PATCH] s390: introduce struct channel_subsystem

struct channel_subsystem encapsulates several per channel subsystem
properties, like status of chpids or the global path group id.

Signed-off-by: Cornelia Huck <cohuck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

6 files changed, 90 insertions, 45 deletions

diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index 78e082311f48..ebd924962df0 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -24,8 +24,6 @@
 #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 +31,13 @@ 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
@@ -219,13 +217,13 @@ 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;
@@ -296,18 +294,20 @@ 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 {
@@ -511,6 +511,7 @@ chsc_process_crw(void)
         ret = 0;
         do {
                 int ccode, status;
+                struct device *dev;
                 memset(sei_area, 0, sizeof(*sei_area));
                 memset(&res_data, 0, sizeof(struct res_acc_data));
                 sei_area->request = (struct chsc_header) {
@@ -586,7 +587,8 @@ chsc_process_crw(void)
                                 new_channel_path(sei_area->rsid);
                         else if (!status)
                                 break;
-                        res_data.chp = chps[sei_area->rsid];
+                        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;
@@ -602,6 +604,7 @@ chsc_process_crw(void)
                         }
                         ret = s390_process_res_acc(&res_data);
                         pr_debug("\n\n");
+                        put_device(dev);
                         break;
                         
                 default: /* other stuff */
@@ -678,6 +681,7 @@ 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 */
@@ -685,11 +689,13 @@ chp_add(int chpid)
         sprintf(dbf_txt, "cadd%x", chpid);
         CIO_TRACE_EVENT(2, dbf_txt);
 
-        rc = for_each_subchannel(__chp_add, chps[chpid]);
+        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;
 }
 
@@ -1016,7 +1022,7 @@ new_channel_path(int chpid)
         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);
@@ -1038,7 +1044,7 @@ new_channel_path(int chpid)
                 device_unregister(&chp->dev);
                 goto out_free;
         } else
-                chps[chpid] = chp;
+                css[0]->chps[chpid] = chp;
         return ret;
 out_free:
         kfree(chp);
@@ -1051,7 +1057,7 @@ 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);
diff --git a/drivers/s390/cio/chsc.h b/drivers/s390/cio/chsc.h
index 69450134bec7..170083ca4349 100644
--- a/drivers/s390/cio/chsc.h
+++ b/drivers/s390/cio/chsc.h
@@ -1,8 +1,6 @@
 #ifndef S390_CHSC_H
 #define S390_CHSC_H
 
-#define NR_CHPIDS 256
-
 #define CHSC_SEI_ACC_CHPID        1
 #define CHSC_SEI_ACC_LINKADDR     2
 #define CHSC_SEI_ACC_FULLLINKADDR 3
@@ -65,4 +63,7 @@ extern int chsc_determine_css_characteristics(void);
 extern int css_characteristics_avail;
 
 extern void *chsc_get_chp_desc(struct subchannel*, int);
+
+#define to_channelpath(dev) container_of(dev, struct channel_path, dev)
+
 #endif
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index dba632a5f71f..b6225cbbbee7 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -24,12 +24,9 @@
 int need_rescan = 0;
 int css_init_done = 0;
 
-struct pgid global_pgid;
-int css_characteristics_avail = 0;
+struct channel_subsystem *css[__MAX_CSSID + 1];
 
-struct device css_bus_device = {
-        .bus_id = "css0",
-};
+int css_characteristics_avail = 0;
 
 inline int
 for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *data)
@@ -112,7 +109,7 @@ css_register_subchannel(struct subchannel *sch)
         int ret;
 
         /* Initialize the subchannel structure */
-        sch->dev.parent = &css_bus_device;
+        sch->dev.parent = &css[0]->device;
         sch->dev.bus = &css_bus_type;
         sch->dev.release = &css_subchannel_release;
         
@@ -421,21 +418,35 @@ __init_channel_subsystem(struct subchannel_id schid, void *data)
 }
 
 static void __init
-css_generate_pgid(void)
+css_generate_pgid(struct channel_subsystem *css, u32 tod_high)
 {
-        /* Let's build our path group ID here. */
-        if (css_characteristics_avail && css_general_characteristics.mcss)
-                global_pgid.cpu_addr = 0x8000;
-        else {
+        if (css_characteristics_avail && css_general_characteristics.mcss) {
+                css->global_pgid.pgid_high.ext_cssid.version = 0x80;
+                css->global_pgid.pgid_high.ext_cssid.cssid = css->cssid;
+        } else {
 #ifdef CONFIG_SMP
-                global_pgid.cpu_addr = hard_smp_processor_id();
+                css->global_pgid.pgid_high.cpu_addr = hard_smp_processor_id();
 #else
-                global_pgid.cpu_addr = 0;
+                css->global_pgid.pgid_high.cpu_addr = 0;
 #endif
         }
-        global_pgid.cpu_id = ((cpuid_t *) __LC_CPUID)->ident;
-        global_pgid.cpu_model = ((cpuid_t *) __LC_CPUID)->machine;
-        global_pgid.tod_high = (__u32) (get_clock() >> 32);
+        css->global_pgid.cpu_id = ((cpuid_t *) __LC_CPUID)->ident;
+        css->global_pgid.cpu_model = ((cpuid_t *) __LC_CPUID)->machine;
+        css->global_pgid.tod_high = tod_high;
+
+}
+
+static inline void __init
+setup_css(int nr)
+{
+        u32 tod_high;
+
+        memset(css[nr], 0, sizeof(struct channel_subsystem));
+        css[nr]->valid = 1;
+        css[nr]->cssid = nr;
+        sprintf(css[nr]->device.bus_id, "css%x", nr);
+        tod_high = (u32) (get_clock() >> 32);
+        css_generate_pgid(css[nr], tod_high);
 }
 
 /*
@@ -446,25 +457,39 @@ css_generate_pgid(void)
 static int __init
 init_channel_subsystem (void)
 {
-        int ret;
+        int ret, i;
 
         if (chsc_determine_css_characteristics() == 0)
                 css_characteristics_avail = 1;
 
-        css_generate_pgid();
-
         if ((ret = bus_register(&css_bus_type)))
                 goto out;
-        if ((ret = device_register (&css_bus_device)))
-                goto out_bus;
 
+        /* Setup css structure. */
+        for (i = 0; i <= __MAX_CSSID; i++) {
+                css[i] = kmalloc(sizeof(struct channel_subsystem), GFP_KERNEL);
+                if (!css[i]) {
+                        ret = -ENOMEM;
+                        goto out_bus;
+                }
+                setup_css(i);
+                ret = device_register(&css[i]->device);
+                if (ret)
+                        goto out_free;
+        }
         css_init_done = 1;
 
         ctl_set_bit(6, 28);
 
         for_each_subchannel(__init_channel_subsystem, NULL);
         return 0;
+out_free:
+        kfree(css[i]);
 out_bus:
+        while (i > 0) {
+                i--;
+                device_unregister(&css[i]->device);
+        }
         bus_unregister(&css_bus_type);
 out:
         return ret;
diff --git a/drivers/s390/cio/css.h b/drivers/s390/cio/css.h
index 71efca25476d..b74659cab0af 100644
--- a/drivers/s390/cio/css.h
+++ b/drivers/s390/cio/css.h
@@ -35,19 +35,25 @@ struct path_state {
         __u8  resvd  : 3;       /* reserved */
 } __attribute__ ((packed));
 
+struct extended_cssid {
+        u8 version;
+        u8 cssid;
+} __attribute__ ((packed));
+
 struct pgid {
         union {
                 __u8 fc;        /* SPID function code */
                 struct path_state ps;   /* SNID path state */
         } inf;
-        __u32 cpu_addr  : 16;   /* CPU address */
+        union {
+                __u32 cpu_addr  : 16;   /* CPU address */
+                struct extended_cssid ext_cssid;
+        } pgid_high;
         __u32 cpu_id    : 24;   /* CPU identification */
         __u32 cpu_model : 16;   /* CPU model */
         __u32 tod_high;         /* high word TOD clock */
 } __attribute__ ((packed));
 
-extern struct pgid global_pgid;
-
 #define MAX_CIWS 8
 
 /*
@@ -129,9 +135,20 @@ extern int css_init_done;
 extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
 
 #define __MAX_SUBCHANNEL 65535
+#define __MAX_CHPID 255
+#define __MAX_CSSID 0
+
+struct channel_subsystem {
+        u8 cssid;
+        int valid;
+        struct channel_path *chps[__MAX_CHPID];
+        struct device device;
+        struct pgid global_pgid;
+};
+#define to_css(dev) container_of(dev, struct channel_subsystem, device)
 
 extern struct bus_type css_bus_type;
-extern struct device css_bus_device;
+extern struct channel_subsystem *css[];
 
 /* Some helper functions for disconnected state. */
 int device_is_disconnected(struct subchannel *);
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 9ac07aeffbe6..ba9f7c11f63f 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -986,10 +986,6 @@ ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
         cdev->dev = (struct device) {
                 .parent = &sch->dev,
         };
-        /* Initialize the subchannel structure */
-        sch->dev.parent = &css_bus_device;
-        sch->dev.bus = &css_bus_type;
-
         rc = io_subchannel_recog(cdev, sch);
         if (rc)
                 return rc;
diff --git a/drivers/s390/cio/device_pgid.c b/drivers/s390/cio/device_pgid.c
index f08e84cc3563..3c89d70b9c09 100644
--- a/drivers/s390/cio/device_pgid.c
+++ b/drivers/s390/cio/device_pgid.c
@@ -164,7 +164,7 @@ ccw_device_sense_pgid_irq(struct ccw_device *cdev, enum dev_event dev_event)
         /* 0, -ETIME, -EOPNOTSUPP, -EAGAIN, -EACCES or -EUSERS */
         case 0:                 /* Sense Path Group ID successful. */
                 if (cdev->private->pgid.inf.ps.state1 == SNID_STATE1_RESET)
-                        memcpy(&cdev->private->pgid, &global_pgid,
+                        memcpy(&cdev->private->pgid, &css[0]->global_pgid,
                                sizeof(struct pgid));
                 ccw_device_sense_pgid_done(cdev, 0);
                 break;