[S390] cio: introduce cio_update_schib

[deliverable/linux.git] / drivers / s390 / cio / cio.c

diff --git a/drivers/s390/cio/cio.c b/drivers/s390/cio/cio.c
index 8047800e9a0c47711ff967207aeaa22a76875b96..9bdb463765c74b460cfb7a7f2db96842b1f75ae3 100644 (file)
--- a/drivers/s390/cio/cio.c
+++ b/drivers/s390/cio/cio.c
@@ -114,11 +114,13 @@ cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
        else
                sch->lpm = 0;
 
-       stsch (sch->schid, &sch->schib);
-
        CIO_MSG_EVENT(2, "cio_start: 'not oper' status for "
                      "subchannel 0.%x.%04x!\n", sch->schid.ssid,
                      sch->schid.sch_no);
+
+       if (cio_update_schib(sch))
+               return -ENODEV;
+
        sprintf(dbf_text, "no%s", dev_name(&sch->dev));
        CIO_TRACE_EVENT(0, dbf_text);
        CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
@@ -316,7 +318,8 @@ cio_cancel (struct subchannel *sch)
        switch (ccode) {
        case 0:         /* success */
                /* Update information in scsw. */
-               stsch (sch->schid, &sch->schib);
+               if (cio_update_schib(sch))
+                       return -ENODEV;
                return 0;
        case 1:         /* status pending */
                return -EBUSY;
@@ -357,6 +360,23 @@ cio_modify (struct subchannel *sch)
        return ret;
 }
 
+/**
+ * cio_update_schib - Perform stsch and update schib if subchannel is valid.
+ * @sch: subchannel on which to perform stsch
+ * Return zero on success, -ENODEV otherwise.
+ */
+int cio_update_schib(struct subchannel *sch)
+{
+       struct schib schib;
+
+       if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
+               return -ENODEV;
+
+       memcpy(&sch->schib, &schib, sizeof(schib));
+       return 0;
+}
+EXPORT_SYMBOL_GPL(cio_update_schib);
+
 /**
  * cio_enable_subchannel - enable a subchannel.
  * @sch: subchannel to be enabled
@@ -365,7 +385,6 @@ cio_modify (struct subchannel *sch)
 int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
 {
        char dbf_txt[15];
-       int ccode;
        int retry;
        int ret;
 
@@ -374,8 +393,7 @@ int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
 
        if (sch_is_pseudo_sch(sch))
                return -EINVAL;
-       ccode = stsch (sch->schid, &sch->schib);
-       if (ccode)
+       if (cio_update_schib(sch))
                return -ENODEV;
 
        for (retry = 5, ret = 0; retry > 0; retry--) {
@@ -392,7 +410,10 @@ int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
                         */
                        sch->schib.pmcw.csense = 0;
                if (ret == 0) {
-                       stsch (sch->schid, &sch->schib);
+                       if (cio_update_schib(sch)) {
+                               ret = -ENODEV;
+                               break;
+                       }
                        if (sch->schib.pmcw.ena)
                                break;
                }
@@ -415,7 +436,6 @@ EXPORT_SYMBOL_GPL(cio_enable_subchannel);
 int cio_disable_subchannel(struct subchannel *sch)
 {
        char dbf_txt[15];
-       int ccode;
        int retry;
        int ret;
 
@@ -424,8 +444,7 @@ int cio_disable_subchannel(struct subchannel *sch)
 
        if (sch_is_pseudo_sch(sch))
                return 0;
-       ccode = stsch (sch->schid, &sch->schib);
-       if (ccode == 3)         /* Not operational. */
+       if (cio_update_schib(sch))
                return -ENODEV;
 
        if (scsw_actl(&sch->schib.scsw) != 0)
@@ -448,7 +467,10 @@ int cio_disable_subchannel(struct subchannel *sch)
                         */
                        break;
                if (ret == 0) {
-                       stsch (sch->schid, &sch->schib);
+                       if (cio_update_schib(sch)) {
+                               ret = -ENODEV;
+                               break;
+                       }
                        if (!sch->schib.pmcw.ena)
                                break;
                }
@@ -851,7 +873,8 @@ __disable_subchannel_easy(struct subchannel_id schid, struct schib *schib)
                cc = msch(schid, schib);
                if (cc)
                        return (cc==3?-ENODEV:-EBUSY);
-               stsch(schid, schib);
+               if (stsch(schid, schib) || !css_sch_is_valid(schib))
+                       return -ENODEV;
                if (!schib->pmcw.ena)
                        return 0;
        }