s390/sclp: Add support for Store Data SCLP interface

Add functions to retrieve data associated with an SCLP Store Data
entity. Automatically retrieve data for the "config" entity during
boot and make that data available to user-space via sysfs:

    /sys/firmware/sclp_sd/config/data
        Reading from this file will return config data contents.

    /sys/firmware/sclp_sd/config/reload
        Writing to this file will cause the latest version of data
        related to the config entity to be read from the SCLP interface.

Generate a KOBJ_CHANGE whenever new data is retrieved.
Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/char/Makefile

@@ -23,7 +23,7 @@ CFLAGS_REMOVE_sclp_early_core.o	+= $(CC_FLAGS_EXPOLINE)
 
 obj-y += ctrlchar.o keyboard.o defkeymap.o sclp.o sclp_rw.o sclp_quiesce.o \
 	 sclp_cmd.o sclp_config.o sclp_cpi_sys.o sclp_ocf.o sclp_ctl.o \
-	 sclp_early.o sclp_early_core.o
+	 sclp_early.o sclp_early_core.o sclp_sd.o
 
 obj-$(CONFIG_TN3270) += raw3270.o
 obj-$(CONFIG_TN3270_CONSOLE) += con3270.o

drivers/s390/char/sclp.h

@@ -28,6 +28,7 @@
 #define EVTYP_PMSGCMD		0x09
 #define EVTYP_ASYNC		0x0A
 #define EVTYP_CTLPROGIDENT	0x0B
+#define EVTYP_STORE_DATA	0x0C
 #define EVTYP_ERRNOTIFY		0x18
 #define EVTYP_VT220MSG		0x1A
 #define EVTYP_SDIAS		0x1C
@@ -42,6 +43,7 @@
 #define EVTYP_PMSGCMD_MASK	SCLP_EVTYP_MASK(EVTYP_PMSGCMD)
 #define EVTYP_ASYNC_MASK	SCLP_EVTYP_MASK(EVTYP_ASYNC)
 #define EVTYP_CTLPROGIDENT_MASK	SCLP_EVTYP_MASK(EVTYP_CTLPROGIDENT)
+#define EVTYP_STORE_DATA_MASK	SCLP_EVTYP_MASK(EVTYP_STORE_DATA)
 #define EVTYP_ERRNOTIFY_MASK	SCLP_EVTYP_MASK(EVTYP_ERRNOTIFY)
 #define EVTYP_VT220MSG_MASK	SCLP_EVTYP_MASK(EVTYP_VT220MSG)
 #define EVTYP_SDIAS_MASK	SCLP_EVTYP_MASK(EVTYP_SDIAS)