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-rw-r--r--kernel/arch/s390/include/asm/facility.h67
1 files changed, 67 insertions, 0 deletions
diff --git a/kernel/arch/s390/include/asm/facility.h b/kernel/arch/s390/include/asm/facility.h
new file mode 100644
index 000000000..0aa6a7ed9
--- /dev/null
+++ b/kernel/arch/s390/include/asm/facility.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright IBM Corp. 1999, 2009
+ *
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#ifndef __ASM_FACILITY_H
+#define __ASM_FACILITY_H
+
+#include <linux/string.h>
+#include <linux/preempt.h>
+#include <asm/lowcore.h>
+
+#define MAX_FACILITY_BIT (256*8) /* stfle_fac_list has 256 bytes */
+
+static inline int __test_facility(unsigned long nr, void *facilities)
+{
+ unsigned char *ptr;
+
+ if (nr >= MAX_FACILITY_BIT)
+ return 0;
+ ptr = (unsigned char *) facilities + (nr >> 3);
+ return (*ptr & (0x80 >> (nr & 7))) != 0;
+}
+
+/*
+ * The test_facility function uses the bit odering where the MSB is bit 0.
+ * That makes it easier to query facility bits with the bit number as
+ * documented in the Principles of Operation.
+ */
+static inline int test_facility(unsigned long nr)
+{
+ return __test_facility(nr, &S390_lowcore.stfle_fac_list);
+}
+
+/**
+ * stfle - Store facility list extended
+ * @stfle_fac_list: array where facility list can be stored
+ * @size: size of passed in array in double words
+ */
+static inline void stfle(u64 *stfle_fac_list, int size)
+{
+ unsigned long nr;
+
+ preempt_disable();
+ asm volatile(
+ " .insn s,0xb2b10000,0(0)\n" /* stfl */
+ "0:\n"
+ EX_TABLE(0b, 0b)
+ : "+m" (S390_lowcore.stfl_fac_list));
+ nr = 4; /* bytes stored by stfl */
+ memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
+ if (S390_lowcore.stfl_fac_list & 0x01000000) {
+ /* More facility bits available with stfle */
+ register unsigned long reg0 asm("0") = size - 1;
+
+ asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */
+ : "+d" (reg0)
+ : "a" (stfle_fac_list)
+ : "memory", "cc");
+ nr = (reg0 + 1) * 8; /* # bytes stored by stfle */
+ }
+ memset((char *) stfle_fac_list + nr, 0, size * 8 - nr);
+ preempt_enable();
+}
+
+#endif /* __ASM_FACILITY_H */