[PATCH] s390: channel path measurements

Gather extended measurements for channel paths from the channel subsystem and
expose them to userspace via a sysfs attribute.

Signed-off-by: Cornelia Huck <cornelia.huck@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, 41 insertions, 0 deletions

diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 3c77d65960db..5b304dbacaeb 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -452,15 +452,50 @@ channel_subsystem_release(struct device *dev)
         struct channel_subsystem *css;
 
         css = to_css(dev);
+        mutex_destroy(&css->mutex);
         kfree(css);
 }
 
+static ssize_t
+css_cm_enable_show(struct device *dev, struct device_attribute *attr,
+                   char *buf)
+{
+        struct channel_subsystem *css = to_css(dev);
+
+        if (!css)
+                return 0;
+        return sprintf(buf, "%x\n", css->cm_enabled);
+}
+
+static ssize_t
+css_cm_enable_store(struct device *dev, struct device_attribute *attr,
+                    const char *buf, size_t count)
+{
+        struct channel_subsystem *css = to_css(dev);
+        int ret;
+
+        switch (buf[0]) {
+        case '0':
+                ret = css->cm_enabled ? chsc_secm(css, 0) : 0;
+                break;
+        case '1':
+                ret = css->cm_enabled ? 0 : chsc_secm(css, 1);
+                break;
+        default:
+                ret = -EINVAL;
+        }
+        return ret < 0 ? ret : count;
+}
+
+static DEVICE_ATTR(cm_enable, 0644, css_cm_enable_show, css_cm_enable_store);
+
 static inline void __init
 setup_css(int nr)
 {
         u32 tod_high;
 
         memset(css[nr], 0, sizeof(struct channel_subsystem));
+        mutex_init(&css[nr]->mutex);
         css[nr]->valid = 1;
         css[nr]->cssid = nr;
         sprintf(css[nr]->device.bus_id, "css%x", nr);
@@ -507,6 +542,9 @@ init_channel_subsystem (void)
                 ret = device_register(&css[i]->device);
                 if (ret)
                         goto out_free;
+                if (css_characteristics_avail && css_chsc_characteristics.secm)
+                        device_create_file(&css[i]->device,
+                                           &dev_attr_cm_enable);
         }
         css_init_done = 1;
 
@@ -519,6 +557,9 @@ out_free:
 out_unregister:
         while (i > 0) {
                 i--;
+                if (css_characteristics_avail && css_chsc_characteristics.secm)
+                        device_remove_file(&css[i]->device,
+                                           &dev_attr_cm_enable);
                 device_unregister(&css[i]->device);
         }
 out_bus: