4 files changed, 191 insertions, 20 deletions

diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index c1c6f1381150..216bc4fba199 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -45,6 +45,7 @@ struct dasd_devmap {
         unsigned int devindex;
         unsigned short features;
         struct dasd_device *device;
+        struct dasd_uid uid;
 };
 
 /*
@@ -716,6 +717,68 @@ dasd_discipline_show(struct device *dev, struct device_attribute *attr, char *bu
 
 static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);
 
+static ssize_t
+dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        struct dasd_devmap *devmap;
+        int alias;
+
+        devmap = dasd_find_busid(dev->bus_id);
+        spin_lock(&dasd_devmap_lock);
+        if (!IS_ERR(devmap))
+                alias = devmap->uid.alias;
+        else
+                alias = 0;
+        spin_unlock(&dasd_devmap_lock);
+
+        return sprintf(buf, alias ? "1\n" : "0\n");
+}
+
+static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);
+
+static ssize_t
+dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        struct dasd_devmap *devmap;
+        char *vendor;
+
+        devmap = dasd_find_busid(dev->bus_id);
+        spin_lock(&dasd_devmap_lock);
+        if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
+                vendor = devmap->uid.vendor;
+        else
+                vendor = "";
+        spin_unlock(&dasd_devmap_lock);
+
+        return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
+}
+
+static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);
+
+#define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
+                     /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1)
+
+static ssize_t
+dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+        struct dasd_devmap *devmap;
+        char uid[UID_STRLEN];
+
+        devmap = dasd_find_busid(dev->bus_id);
+        spin_lock(&dasd_devmap_lock);
+        if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
+                snprintf(uid, sizeof(uid), "%s.%s.%04x.%02x",
+                         devmap->uid.vendor, devmap->uid.serial,
+                         devmap->uid.ssid, devmap->uid.unit_addr);
+        else
+                uid[0] = 0;
+        spin_unlock(&dasd_devmap_lock);
+
+        return snprintf(buf, PAGE_SIZE, "%s\n", uid);
+}
+
+static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);
+
 /*
  * extended error-reporting
  */
@@ -759,6 +822,9 @@ static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);
 static struct attribute * dasd_attrs[] = {
         &dev_attr_readonly.attr,
         &dev_attr_discipline.attr,
+        &dev_attr_alias.attr,
+        &dev_attr_vendor.attr,
+        &dev_attr_uid.attr,
         &dev_attr_use_diag.attr,
         &dev_attr_eer_enabled.attr,
         NULL,
@@ -768,6 +834,42 @@ static struct attribute_group dasd_attr_group = {
         .attrs = dasd_attrs,
 };
 
+
+/*
+ * Return copy of the device unique identifier.
+ */
+int
+dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
+{
+        struct dasd_devmap *devmap;
+
+        devmap = dasd_find_busid(cdev->dev.bus_id);
+        if (IS_ERR(devmap))
+                return PTR_ERR(devmap);
+        spin_lock(&dasd_devmap_lock);
+        *uid = devmap->uid;
+        spin_unlock(&dasd_devmap_lock);
+        return 0;
+}
+
+/*
+ * Register the given device unique identifier into devmap struct.
+ */
+int
+dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
+{
+        struct dasd_devmap *devmap;
+
+        devmap = dasd_find_busid(cdev->dev.bus_id);
+        if (IS_ERR(devmap))
+                return PTR_ERR(devmap);
+        spin_lock(&dasd_devmap_lock);
+        devmap->uid = *uid;
+        spin_unlock(&dasd_devmap_lock);
+        return 0;
+}
+EXPORT_SYMBOL(dasd_set_uid);
+
 /*
  * Return value of the specified feature.
  */
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index ee09ef33d08d..7d5a6cee4bd8 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -446,6 +446,39 @@ dasd_eckd_cdl_reclen(int recid)
         return LABEL_SIZE;
 }
 
+/*
+ * Generate device unique id that specifies the physical device.
+ */
+static int
+dasd_eckd_generate_uid(struct dasd_device *device, struct dasd_uid *uid)
+{
+        struct dasd_eckd_private *private;
+        struct dasd_eckd_confdata *confdata;
+
+        private = (struct dasd_eckd_private *) device->private;
+        if (!private)
+                return -ENODEV;
+        confdata = &private->conf_data;
+        if (!confdata)
+                return -ENODEV;
+
+        memset(uid, 0, sizeof(struct dasd_uid));
+        strncpy(uid->vendor, confdata->ned1.HDA_manufacturer,
+                sizeof(uid->vendor) - 1);
+        EBCASC(uid->vendor, sizeof(uid->vendor) - 1);
+        strncpy(uid->serial, confdata->ned1.HDA_location,
+                sizeof(uid->serial) - 1);
+        EBCASC(uid->serial, sizeof(uid->serial) - 1);
+        uid->ssid = confdata->neq.subsystemID;
+        if (confdata->ned2.sneq.flags == 0x40) {
+                uid->alias = 1;
+                uid->unit_addr = confdata->ned2.sneq.base_unit_addr;
+        } else
+                uid->unit_addr = confdata->ned1.unit_addr;
+
+        return 0;
+}
+
 static int
 dasd_eckd_read_conf(struct dasd_device *device)
 {
@@ -507,11 +540,15 @@ dasd_eckd_read_conf(struct dasd_device *device)
         return 0;
 }
 
-
+/*
+ * Check device characteristics.
+ * If the device is accessible using ECKD discipline, the device is enabled.
+ */
 static int
 dasd_eckd_check_characteristics(struct dasd_device *device)
 {
         struct dasd_eckd_private *private;
+        struct dasd_uid uid;
         void *rdc_data;
         int rc;
 
@@ -536,6 +573,7 @@ dasd_eckd_check_characteristics(struct dasd_device *device)
 
         /* Read Device Characteristics */
         rdc_data = (void *) &(private->rdc_data);
+        memset(rdc_data, 0, sizeof(rdc_data));
         rc = read_dev_chars(device->cdev, &rdc_data, 64);
         if (rc) {
                 DEV_MESSAGE(KERN_WARNING, device,
@@ -556,8 +594,17 @@ dasd_eckd_check_characteristics(struct dasd_device *device)
 
         /* Read Configuration Data */
         rc = dasd_eckd_read_conf (device);
-        return rc;
+        if (rc)
+                return rc;
+
+        /* Generate device unique id and register in devmap */
+        rc = dasd_eckd_generate_uid(device, &uid);
+        if (rc)
+                return rc;
 
+        rc = dasd_set_uid(device->cdev, &uid);
+
+        return rc;
 }
 
 static struct dasd_ccw_req *
diff --git a/drivers/s390/block/dasd_eckd.h b/drivers/s390/block/dasd_eckd.h
index ad8524bb7bb3..d5734e976e1c 100644
--- a/drivers/s390/block/dasd_eckd.h
+++ b/drivers/s390/block/dasd_eckd.h
@@ -228,26 +228,36 @@ struct dasd_eckd_confdata {
                 unsigned char HDA_manufacturer[3];
                 unsigned char HDA_location[2];
                 unsigned char HDA_seqno[12];
-                __u16 ID;
+                __u8 ID;
+                __u8 unit_addr;
         } __attribute__ ((packed)) ned1;
-        struct {
+        union {
                 struct {
-                        unsigned char identifier:2;
-                        unsigned char token_id:1;
-                        unsigned char sno_valid:1;
-                        unsigned char subst_sno:1;
-                        unsigned char recNED:1;
-                        unsigned char emuNED:1;
-                        unsigned char reserved:1;
-                } __attribute__ ((packed)) flags;
-                __u8 descriptor;
-                __u8 reserved[2];
-                unsigned char dev_type[6];
-                unsigned char dev_model[3];
-                unsigned char DASD_manufacturer[3];
-                unsigned char DASD_location[2];
-                unsigned char DASD_seqno[12];
-                __u16 ID;
+                        struct {
+                                unsigned char identifier:2;
+                                unsigned char token_id:1;
+                                unsigned char sno_valid:1;
+                                unsigned char subst_sno:1;
+                                unsigned char recNED:1;
+                                unsigned char emuNED:1;
+                                unsigned char reserved:1;
+                        } __attribute__ ((packed)) flags;
+                        __u8 descriptor;
+                        __u8 reserved[2];
+                        unsigned char dev_type[6];
+                        unsigned char dev_model[3];
+                        unsigned char DASD_manufacturer[3];
+                        unsigned char DASD_location[2];
+                        unsigned char DASD_seqno[12];
+                        __u16 ID;
+                } __attribute__ ((packed)) ned;
+                struct {
+                        unsigned char flags;            /* byte  0    */
+                        unsigned char res2[7];          /* byte  1- 7 */
+                        unsigned char sua_flags;        /* byte  8    */
+                        __u8 base_unit_addr;            /* byte  9    */
+                        unsigned char res3[22];         /* byte 10-31 */
+                } __attribute__ ((packed)) sneq;
         } __attribute__ ((packed)) ned2;
         struct {
                 struct {
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 4293ba827523..d4b13e300a76 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -268,6 +268,16 @@ struct dasd_discipline {
 
 extern struct dasd_discipline *dasd_diag_discipline_pointer;
 
+/*
+ * Unique identifier for dasd device.
+ */
+struct dasd_uid {
+        __u8 alias;
+        char vendor[4];
+        char serial[15];
+        __u16 ssid;
+        __u8 unit_addr;
+};
 
 /*
  * Notification numbers for extended error reporting notifications:
@@ -516,6 +526,8 @@ void dasd_devmap_exit(void);
 struct dasd_device *dasd_create_device(struct ccw_device *);
 void dasd_delete_device(struct dasd_device *);
 
+int dasd_get_uid(struct ccw_device *, struct dasd_uid *);
+int dasd_set_uid(struct ccw_device *, struct dasd_uid *);
 int dasd_get_feature(struct ccw_device *, int);
 int dasd_set_feature(struct ccw_device *, int, int);