[PATCH] s390: multiple subchannel sets support

Add support for multiple subchannel sets.  Works with arbitrary devices in
subchannel set 1 and is transparent to device drivers.  Although currently
only two subchannel sets are available, this will work with the architectured
maximum number of subchannel sets as well.

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>

1 files changed, 60 insertions, 8 deletions

diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c
index ebd924962df0..7270808c02d1 100644
--- a/drivers/s390/cio/chsc.c
+++ b/drivers/s390/cio/chsc.c
@@ -1,7 +1,7 @@
 /*
  *  drivers/s390/cio/chsc.c
  *   S/390 common I/O routines -- channel subsystem call
- *   $Revision: 1.120 $
+ *   $Revision: 1.126 $
  *
  *    Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
  *                            IBM Corporation
@@ -75,7 +75,9 @@ 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 */
@@ -102,6 +104,7 @@ chsc_get_sch_desc_irq(struct subchannel *sch, void *page)
                 .code   = 0x0004,
         };
 
+        ssd_area->ssid = sch->schid.ssid;
         ssd_area->f_sch = sch->schid.sch_no;
         ssd_area->l_sch = sch->schid.sch_no;
 
@@ -145,8 +148,8 @@ 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->schid.sch_no);
+                              " 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
@@ -155,8 +158,9 @@ 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->schid.sch_no, 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;
@@ -364,7 +368,7 @@ s390_process_res_acc_new_sch(struct subchannel_id schid)
          * that beast may be on we'll have to do a stsch
          * on all devices, grr...
          */
-        if (stsch(schid, &schib))
+        if (stsch_err(schid, &schib))
                 /* We're through */
                 return need_rescan ? -EAGAIN : -ENXIO;
 
@@ -818,7 +822,7 @@ __s390_vary_chpid_on(struct subchannel_id schid, void *data)
                 put_device(&sch->dev);
                 return 0;
         }
-        if (stsch(schid, &schib))
+        if (stsch_err(schid, &schib))
                 /* We're through */
                 return -ENXIO;
         /* Put it on the slow path. */
@@ -1078,6 +1082,54 @@ 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 = (struct chsc_header) {
+                .length = 0x0400,
+                .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 0x0003: /* invalid request block */
+        case 0x0007:
+                ret = -EINVAL;
+                break;
+        case 0x0004: /* command not provided */
+        case 0x0101: /* facility not provided */
+                ret = -EOPNOTSUPP;
+                break;
+        }
+ out:
+        free_page((unsigned long)sda_area);
+        return ret;
+}
+
 subsys_initcall(chsc_alloc_sei_area);
 
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