[S390] dasd: add High Performance FICON support

[deliverable/linux.git] / drivers / s390 / block / dasd_devmap.c

diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index 2ef25731d197ed0f6a9ce2fdfdc1fc4358b9e460..da231a787ceebda3ea129730e545d3ca95ddcdc1 100644 (file)
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -67,6 +67,8 @@ int dasd_probeonly =  0;      /* is true, when probeonly mode is active */
 int dasd_autodetect = 0;       /* is true, when autodetection is active */
 int dasd_nopav = 0;            /* is true, when PAV is disabled */
 EXPORT_SYMBOL_GPL(dasd_nopav);
+int dasd_nofcx;                        /* disable High Performance Ficon */
+EXPORT_SYMBOL_GPL(dasd_nofcx);
 
 /*
  * char *dasd[] is intended to hold the ranges supplied by the dasd= statement
@@ -206,6 +208,8 @@ dasd_feature_list(char *str, char **endp)
                        features |= DASD_FEATURE_USEDIAG;
                else if (len == 6 && !strncmp(str, "erplog", 6))
                        features |= DASD_FEATURE_ERPLOG;
+               else if (len == 8 && !strncmp(str, "failfast", 8))
+                       features |= DASD_FEATURE_FAILFAST;
                else {
                        MESSAGE(KERN_WARNING,
                                "unsupported feature: %*s, "
@@ -270,6 +274,11 @@ dasd_parse_keyword( char *parsestring ) {
                }
                return residual_str;
        }
+       if (strncmp("nofcx", parsestring, length) == 0) {
+               dasd_nofcx = 1;
+               MESSAGE(KERN_INFO, "%s", "disable High Performance Ficon");
+               return residual_str;
+       }
        if (strncmp("fixedbuffers", parsestring, length) == 0) {
                if (dasd_page_cache)
                        return residual_str;
@@ -666,6 +675,51 @@ dasd_device_from_cdev(struct ccw_device *cdev)
  * SECTION: files in sysfs
  */
 
+/*
+ * failfast controls the behaviour, if no path is available
+ */
+static ssize_t dasd_ff_show(struct device *dev, struct device_attribute *attr,
+                           char *buf)
+{
+       struct dasd_devmap *devmap;
+       int ff_flag;
+
+       devmap = dasd_find_busid(dev_name(dev));
+       if (!IS_ERR(devmap))
+               ff_flag = (devmap->features & DASD_FEATURE_FAILFAST) != 0;
+       else
+               ff_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_FAILFAST) != 0;
+       return snprintf(buf, PAGE_SIZE, ff_flag ? "1\n" : "0\n");
+}
+
+static ssize_t dasd_ff_store(struct device *dev, struct device_attribute *attr,
+             const char *buf, size_t count)
+{
+       struct dasd_devmap *devmap;
+       int val;
+       char *endp;
+
+       devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+       if (IS_ERR(devmap))
+               return PTR_ERR(devmap);
+
+       val = simple_strtoul(buf, &endp, 0);
+       if (((endp + 1) < (buf + count)) || (val > 1))
+               return -EINVAL;
+
+       spin_lock(&dasd_devmap_lock);
+       if (val)
+               devmap->features |= DASD_FEATURE_FAILFAST;
+       else
+               devmap->features &= ~DASD_FEATURE_FAILFAST;
+       if (devmap->device)
+               devmap->device->features = devmap->features;
+       spin_unlock(&dasd_devmap_lock);
+       return count;
+}
+
+static DEVICE_ATTR(failfast, 0644, dasd_ff_show, dasd_ff_store);
+
 /*
  * readonly controls the readonly status of a dasd
  */
@@ -1020,6 +1074,7 @@ static struct attribute * dasd_attrs[] = {
        &dev_attr_use_diag.attr,
        &dev_attr_eer_enabled.attr,
        &dev_attr_erplog.attr,
+       &dev_attr_failfast.attr,
        NULL,
 };