[S390] dasd: Add support for enhanced VM UID

When z/VM provides two virtual devices (minidisks) that reside on the
same real device, both will receive the configuration data from the
real device and thus get the same uid. To fix this problem, z/VM
provides an additional configuration data record that allows to
distinguish between minidisks.
z/VM APAR VM64273 needs be installed so this fix has an effect.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

5 files changed, 189 insertions, 163 deletions

diff --git a/drivers/s390/block/dasd_alias.c b/drivers/s390/block/dasd_alias.c
index 2d8df0b..20676cd 100644
--- a/drivers/s390/block/dasd_alias.c
+++ b/drivers/s390/block/dasd_alias.c
@@ -91,7 +91,8 @@ static struct alias_pav_group *_find_group(struct alias_lcu *lcu,
 	else
 		search_unit_addr = uid->base_unit_addr;
 	list_for_each_entry(pos, &lcu->grouplist, group) {
-		if (pos->uid.base_unit_addr == search_unit_addr)
+		if (pos->uid.base_unit_addr == search_unit_addr &&
+		    !strncmp(pos->uid.vduit, uid->vduit, sizeof(uid->vduit)))
 			return pos;
 	};
 	return NULL;
@@ -332,6 +333,7 @@ static int _add_device_to_lcu(struct alias_lcu *lcu,
 			group->uid.base_unit_addr = uid->real_unit_addr;
 		else
 			group->uid.base_unit_addr = uid->base_unit_addr;
+		memcpy(group->uid.vduit, uid->vduit, sizeof(uid->vduit));
 		INIT_LIST_HEAD(&group->group);
 		INIT_LIST_HEAD(&group->baselist);
 		INIT_LIST_HEAD(&group->aliaslist);
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index d774e79..cd3335c 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -913,7 +913,8 @@ dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
 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)
+		     /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1 +\
+		     /* vduit */ 32 + 1)
 
 static ssize_t
 dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
@@ -945,8 +946,17 @@ dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
 		sprintf(ua_string, "%02x", uid->real_unit_addr);
 		break;
 	}
-	snprintf(uid_string, sizeof(uid_string), "%s.%s.%04x.%s",
-		 uid->vendor, uid->serial, uid->ssid, ua_string);
+	if (strlen(uid->vduit) > 0)
+		snprintf(uid_string, sizeof(uid_string),
+			 "%s.%s.%04x.%s.%s",
+			 uid->vendor, uid->serial,
+			 uid->ssid, ua_string,
+			 uid->vduit);
+	else
+		snprintf(uid_string, sizeof(uid_string),
+			 "%s.%s.%04x.%s",
+			 uid->vendor, uid->serial,
+			 uid->ssid, ua_string);
 	spin_unlock(&dasd_devmap_lock);
 	return snprintf(buf, PAGE_SIZE, "%s\n", uid_string);
 }
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 3590fdb..773b3fe 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -313,8 +313,8 @@ static int prefix(struct ccw1 *ccw, struct PFX_eckd_data *pfxdata, int trk,
 	memset(pfxdata, 0, sizeof(*pfxdata));
 	/* prefix data */
 	pfxdata->format = 0;
-	pfxdata->base_address = basepriv->conf_data.ned1.unit_addr;
-	pfxdata->base_lss = basepriv->conf_data.ned1.ID;
+	pfxdata->base_address = basepriv->ned->unit_addr;
+	pfxdata->base_lss = basepriv->ned->ID;
 	pfxdata->validity.define_extend = 1;
 
 	/* private uid is kept up to date, conf_data may be outdated */
@@ -536,36 +536,40 @@ dasd_eckd_cdl_reclen(int recid)
 /*
  * Generate device unique id that specifies the physical device.
  */
-static int
-dasd_eckd_generate_uid(struct dasd_device *device, struct dasd_uid *uid)
+static int dasd_eckd_generate_uid(struct dasd_device *device,
+				  struct dasd_uid *uid)
 {
 	struct dasd_eckd_private *private;
-	struct dasd_eckd_confdata *confdata;
+	int count;
 
 	private = (struct dasd_eckd_private *) device->private;
 	if (!private)
 		return -ENODEV;
-	confdata = &private->conf_data;
-	if (!confdata)
+	if (!private->ned || !private->gneq)
 		return -ENODEV;
 
 	memset(uid, 0, sizeof(struct dasd_uid));
-	memcpy(uid->vendor, confdata->ned1.HDA_manufacturer,
+	memcpy(uid->vendor, private->ned->HDA_manufacturer,
 	       sizeof(uid->vendor) - 1);
 	EBCASC(uid->vendor, sizeof(uid->vendor) - 1);
-	memcpy(uid->serial, confdata->ned1.HDA_location,
+	memcpy(uid->serial, private->ned->HDA_location,
 	       sizeof(uid->serial) - 1);
 	EBCASC(uid->serial, sizeof(uid->serial) - 1);
-	uid->ssid = confdata->neq.subsystemID;
-	uid->real_unit_addr = confdata->ned1.unit_addr;
-	if (confdata->ned2.sneq.flags == 0x40 &&
-	    confdata->ned2.sneq.format == 0x0001) {
-		uid->type = confdata->ned2.sneq.sua_flags;
+	uid->ssid = private->gneq->subsystemID;
+	uid->real_unit_addr = private->ned->unit_addr;;
+	if (private->sneq) {
+		uid->type = private->sneq->sua_flags;
 		if (uid->type == UA_BASE_PAV_ALIAS)
-			uid->base_unit_addr = confdata->ned2.sneq.base_unit_addr;
+			uid->base_unit_addr = private->sneq->base_unit_addr;
 	} else {
 		uid->type = UA_BASE_DEVICE;
 	}
+	if (private->vdsneq) {
+		for (count = 0; count < 16; count++) {
+			sprintf(uid->vduit+2*count, "%02x",
+				private->vdsneq->uit[count]);
+		}
+	}
 	return 0;
 }
 
@@ -623,6 +627,15 @@ static int dasd_eckd_read_conf_lpm(struct dasd_device *device,
 		ret = -ENOMEM;
 		goto out_error;
 	}
+
+	/*
+	 * buffer has to start with EBCDIC "V1.0" to show
+	 * support for virtual device SNEQ
+	 */
+	rcd_buf[0] = 0xE5;
+	rcd_buf[1] = 0xF1;
+	rcd_buf[2] = 0x4B;
+	rcd_buf[3] = 0xF0;
 	cqr = dasd_eckd_build_rcd_lpm(device, rcd_buf, ciw, lpm);
 	if (IS_ERR(cqr)) {
 		ret =  PTR_ERR(cqr);
@@ -646,8 +659,62 @@ out_error:
 	return ret;
 }
 
-static int
-dasd_eckd_read_conf(struct dasd_device *device)
+static int dasd_eckd_identify_conf_parts(struct dasd_eckd_private *private)
+{
+
+	struct dasd_sneq *sneq;
+	int i, count;
+
+	private->ned = NULL;
+	private->sneq = NULL;
+	private->vdsneq = NULL;
+	private->gneq = NULL;
+	count = private->conf_len / sizeof(struct dasd_sneq);
+	sneq = (struct dasd_sneq *)private->conf_data;
+	for (i = 0; i < count; ++i) {
+		if (sneq->flags.identifier == 1 && sneq->format == 1)
+			private->sneq = sneq;
+		else if (sneq->flags.identifier == 1 && sneq->format == 4)
+			private->vdsneq = (struct vd_sneq *)sneq;
+		else if (sneq->flags.identifier == 2)
+			private->gneq = (struct dasd_gneq *)sneq;
+		else if (sneq->flags.identifier == 3 && sneq->res1 == 1)
+			private->ned = (struct dasd_ned *)sneq;
+		sneq++;
+	}
+	if (!private->ned || !private->gneq) {
+		private->ned = NULL;
+		private->sneq = NULL;
+		private->vdsneq = NULL;
+		private->gneq = NULL;
+		return -EINVAL;
+	}
+	return 0;
+
+};
+
+static unsigned char dasd_eckd_path_access(void *conf_data, int conf_len)
+{
+	struct dasd_gneq *gneq;
+	int i, count, found;
+
+	count = conf_len / sizeof(*gneq);
+	gneq = (struct dasd_gneq *)conf_data;
+	found = 0;
+	for (i = 0; i < count; ++i) {
+		if (gneq->flags.identifier == 2) {
+			found = 1;
+			break;
+		}
+		gneq++;
+	}
+	if (found)
+		return ((char *)gneq)[18] & 0x07;
+	else
+		return 0;
+}
+
+static int dasd_eckd_read_conf(struct dasd_device *device)
 {
 	void *conf_data;
 	int conf_len, conf_data_saved;
@@ -661,7 +728,6 @@ dasd_eckd_read_conf(struct dasd_device *device)
 	path_data->opm = ccw_device_get_path_mask(device->cdev);
 	lpm = 0x80;
 	conf_data_saved = 0;
-
 	/* get configuration data per operational path */
 	for (lpm = 0x80; lpm; lpm>>= 1) {
 		if (lpm & path_data->opm){
@@ -678,22 +744,20 @@ dasd_eckd_read_conf(struct dasd_device *device)
 					"data retrieved");
 				continue;	/* no error */
 			}
-			if (conf_len != sizeof(struct dasd_eckd_confdata)) {
-				MESSAGE(KERN_WARNING,
-					"sizes of configuration data mismatch"
-					"%d (read) vs %ld (expected)",
-					conf_len,
-					sizeof(struct dasd_eckd_confdata));
-				kfree(conf_data);
-				continue;	/* no error */
-			}
 			/* save first valid configuration data */
-			if (!conf_data_saved){
-				memcpy(&private->conf_data, conf_data,
-				       sizeof(struct dasd_eckd_confdata));
+			if (!conf_data_saved) {
+				kfree(private->conf_data);
+				private->conf_data = conf_data;
+				private->conf_len = conf_len;
+				if (dasd_eckd_identify_conf_parts(private)) {
+					private->conf_data = NULL;
+					private->conf_len = 0;
+					kfree(conf_data);
+					continue;
+				}
 				conf_data_saved++;
 			}
-			switch (((char *)conf_data)[242] & 0x07){
+			switch (dasd_eckd_path_access(conf_data, conf_len)) {
 			case 0x02:
 				path_data->npm |= lpm;
 				break;
@@ -701,7 +765,8 @@ dasd_eckd_read_conf(struct dasd_device *device)
 				path_data->ppm |= lpm;
 				break;
 			}
-			kfree(conf_data);
+			if (conf_data != private->conf_data)
+				kfree(conf_data);
 		}
 	}
 	return 0;
@@ -952,6 +1017,7 @@ out_err2:
 	dasd_free_block(device->block);
 	device->block = NULL;
 out_err1:
+	kfree(private->conf_data);
 	kfree(device->private);
 	device->private = NULL;
 	return rc;
@@ -959,7 +1025,17 @@ out_err1:
 
 static void dasd_eckd_uncheck_device(struct dasd_device *device)
 {
+	struct dasd_eckd_private *private;
+
+	private = (struct dasd_eckd_private *) device->private;
 	dasd_alias_disconnect_device_from_lcu(device);
+	private->ned = NULL;
+	private->sneq = NULL;
+	private->vdsneq = NULL;
+	private->gneq = NULL;
+	private->conf_len = 0;
+	kfree(private->conf_data);
+	private->conf_data = NULL;
 }
 
 static struct dasd_ccw_req *
@@ -1746,9 +1822,10 @@ dasd_eckd_fill_info(struct dasd_device * device,
 	info->characteristics_size = sizeof(struct dasd_eckd_characteristics);
 	memcpy(info->characteristics, &private->rdc_data,
 	       sizeof(struct dasd_eckd_characteristics));
-	info->confdata_size = sizeof(struct dasd_eckd_confdata);
-	memcpy(info->configuration_data, &private->conf_data,
-	       sizeof(struct dasd_eckd_confdata));
+	info->confdata_size = min((unsigned long)private->conf_len,
+				  sizeof(info->configuration_data));
+	memcpy(info->configuration_data, private->conf_data,
+	       info->confdata_size);
 	return 0;
 }
 
diff --git a/drivers/s390/block/dasd_eckd.h b/drivers/s390/block/dasd_eckd.h
index fc2509c..4bf0aa5 100644
--- a/drivers/s390/block/dasd_eckd.h
+++ b/drivers/s390/block/dasd_eckd.h
@@ -231,133 +231,62 @@ struct dasd_eckd_characteristics {
 	__u8 reserved3[10];
 } __attribute__ ((packed));
 
-struct dasd_eckd_confdata {
+/* elements of the configuration data */
+struct dasd_ned {
 	struct {
-		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 dev_class;
-		__u8 reserved;
-		unsigned char dev_type[6];
-		unsigned char dev_model[3];
-		unsigned char HDA_manufacturer[3];
-		unsigned char HDA_location[2];
-		unsigned char HDA_seqno[12];
-		__u8 ID;
-		__u8 unit_addr;
-	} __attribute__ ((packed)) ned1;
-	union {
-		struct {
-			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 res1;		/* byte  1    */
-			__u16 format;			/* byte  2-3  */
-			unsigned char res2[4];		/* byte  4-7  */
-			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;
+		__u8 identifier:2;
+		__u8 token_id:1;
+		__u8 sno_valid:1;
+		__u8 subst_sno:1;
+		__u8 recNED:1;
+		__u8 emuNED:1;
+		__u8 reserved:1;
+	} __attribute__ ((packed)) flags;
+	__u8 descriptor;
+	__u8 dev_class;
+	__u8 reserved;
+	__u8 dev_type[6];
+	__u8 dev_model[3];
+	__u8 HDA_manufacturer[3];
+	__u8 HDA_location[2];
+	__u8 HDA_seqno[12];
+	__u8 ID;
+	__u8 unit_addr;
+} __attribute__ ((packed));
+
+struct dasd_sneq {
 	struct {
-		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 cont_type[6];
-		unsigned char cont_model[3];
-		unsigned char cont_manufacturer[3];
-		unsigned char cont_location[2];
-		unsigned char cont_seqno[12];
-		__u16 ID;
-	} __attribute__ ((packed)) ned3;
+		__u8 identifier:2;
+		__u8 reserved:6;
+	} __attribute__ ((packed)) flags;
+	__u8 res1;
+	__u16 format;
+	__u8 res2[4];		/* byte  4- 7 */
+	__u8 sua_flags;		/* byte  8    */
+	__u8 base_unit_addr;	/* byte  9    */
+	__u8 res3[22];		/* byte 10-31 */
+} __attribute__ ((packed));
+
+struct vd_sneq {
 	struct {
-		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 cont_type[6];
-		unsigned char empty[3];
-		unsigned char cont_manufacturer[3];
-		unsigned char cont_location[2];
-		unsigned char cont_seqno[12];
-		__u16 ID;
-	} __attribute__ ((packed)) ned4;
-	unsigned char ned5[32];
-	unsigned char ned6[32];
-	unsigned char ned7[32];
+		__u8 identifier:2;
+		__u8 reserved:6;
+	} __attribute__ ((packed)) flags;
+	__u8 res1;
+	__u16 format;
+	__u8 res2[4];	/* byte  4- 7 */
+	__u8 uit[16];	/* byte  8-23 */
+	__u8 res3[8];	/* byte 24-31 */
+} __attribute__ ((packed));
+
+struct dasd_gneq {
 	struct {
-		struct {
-			unsigned char identifier:2;
-			unsigned char reserved:6;
-		} __attribute__ ((packed)) flags;
-		__u8 selector;
-		__u16 interfaceID;
-		__u32 reserved;
-		__u16 subsystemID;
-		struct {
-			unsigned char sp0:1;
-			unsigned char sp1:1;
-			unsigned char reserved:5;
-			unsigned char scluster:1;
-		} __attribute__ ((packed)) spathID;
-		__u8 unit_address;
-		__u8 dev_ID;
-		__u8 dev_address;
-		__u8 adapterID;
-		__u16 link_address;
-		struct {
-			unsigned char parallel:1;
-			unsigned char escon:1;
-			unsigned char reserved:1;
-			unsigned char ficon:1;
-			unsigned char reserved2:4;
-		} __attribute__ ((packed)) protocol_type;
-		struct {
-			unsigned char PID_in_236:1;
-			unsigned char reserved:7;
-		} __attribute__ ((packed)) format_flags;
-		__u8 log_dev_address;
-		unsigned char reserved2[12];
-	} __attribute__ ((packed)) neq;
+		__u8 identifier:2;
+		__u8 reserved:6;
+	} __attribute__ ((packed)) flags;
+	__u8 reserved[7];
+	__u16 subsystemID;
+	__u8 reserved2[22];
 } __attribute__ ((packed));
 
 struct dasd_eckd_path {
@@ -463,7 +392,14 @@ struct alias_pav_group {
 
 struct dasd_eckd_private {
 	struct dasd_eckd_characteristics rdc_data;
-	struct dasd_eckd_confdata conf_data;
+	u8 *conf_data;
+	int conf_len;
+	/* pointers to specific parts in the conf_data */
+	struct dasd_ned *ned;
+	struct dasd_sneq *sneq;
+	struct vd_sneq *vdsneq;
+	struct dasd_gneq *gneq;
+
 	struct dasd_eckd_path path_data;
 	struct eckd_count count_area[5];
 	int init_cqr_status;
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index fb2f931..31ecaa4 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -307,6 +307,7 @@ struct dasd_uid {
 	__u16 ssid;
 	__u8 real_unit_addr;
 	__u8 base_unit_addr;
+	char vduit[33];
 };
 
 /*