s390/lowcore: Convert relocated lowcore alternative to machine feature

Convert the explicit relocated lowcore alternative type to a more
generic machine feature. This only reduces the number of alternative
types, but has no impact on code generation.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

11 files changed, 18 insertions, 23 deletions

diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c
index d3731f2983b7..13316bfa589c 100644
--- a/arch/s390/boot/ipl_parm.c
+++ b/arch/s390/boot/ipl_parm.c
@@ -5,6 +5,7 @@
 #include <linux/pgtable.h>
 #include <asm/abs_lowcore.h>
 #include <asm/page-states.h>
+#include <asm/machine.h>
 #include <asm/ebcdic.h>
 #include <asm/sclp.h>
 #include <asm/sections.h>
@@ -312,7 +313,7 @@ void parse_boot_command_line(void)
 		}
 #endif
 		if (!strcmp(param, "relocate_lowcore") && test_facility(193))
-			relocate_lowcore = 1;
+			set_machine_feature(MFEATURE_LOWCORE);
 		if (!strcmp(param, "earlyprintk"))
 			boot_earlyprintk = true;
 		if (!strcmp(param, "debug"))
diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 72d48e1d67be..f8e6d7eb7cc2 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -34,7 +34,6 @@ unsigned long __bootdata_preserved(max_mappable);
 unsigned long __bootdata_preserved(page_noexec_mask);
 unsigned long __bootdata_preserved(segment_noexec_mask);
 unsigned long __bootdata_preserved(region_noexec_mask);
-int __bootdata_preserved(relocate_lowcore);
 
 u64 __bootdata_preserved(stfle_fac_list[16]);
 struct oldmem_data __bootdata_preserved(oldmem_data);
diff --git a/arch/s390/boot/vmem.c b/arch/s390/boot/vmem.c
index 1e87cffac2f1..1d073acd05a7 100644
--- a/arch/s390/boot/vmem.c
+++ b/arch/s390/boot/vmem.c
@@ -11,6 +11,7 @@
 #include <asm/ctlreg.h>
 #include <asm/physmem_info.h>
 #include <asm/maccess.h>
+#include <asm/machine.h>
 #include <asm/abs_lowcore.h>
 #include "decompressor.h"
 #include "boot.h"
@@ -517,7 +518,7 @@ void setup_vmem(unsigned long kernel_start, unsigned long kernel_end, unsigned l
 	__arch_set_page_dat((void *)swapper_pg_dir, 1UL << CRST_ALLOC_ORDER);
 	__arch_set_page_dat((void *)invalid_pg_dir, 1UL << CRST_ALLOC_ORDER);
 
-	if (relocate_lowcore)
+	if (machine_has_relocated_lowcore())
 		lowcore_address = LOWCORE_ALT_ADDRESS;
 
 	/*
diff --git a/arch/s390/include/asm/abs_lowcore.h b/arch/s390/include/asm/abs_lowcore.h
index 004d17ea05cf..317c07c09ae4 100644
--- a/arch/s390/include/asm/abs_lowcore.h
+++ b/arch/s390/include/asm/abs_lowcore.h
@@ -25,11 +25,4 @@ static inline void put_abs_lowcore(struct lowcore *lc)
 	put_cpu();
 }
 
-extern int relocate_lowcore;
-
-static inline int have_relocated_lowcore(void)
-{
-	return relocate_lowcore;
-}
-
 #endif /* _ASM_S390_ABS_LOWCORE_H */
diff --git a/arch/s390/include/asm/alternative.h b/arch/s390/include/asm/alternative.h
index 67abef07ac93..c7bf60a541e9 100644
--- a/arch/s390/include/asm/alternative.h
+++ b/arch/s390/include/asm/alternative.h
@@ -34,7 +34,6 @@
 #define ALT_TYPE_FACILITY	0
 #define ALT_TYPE_FEATURE	1
 #define ALT_TYPE_SPEC		2
-#define ALT_TYPE_LOWCORE	3
 
 #define ALT_DATA_SHIFT		0
 #define ALT_TYPE_SHIFT		20
@@ -52,9 +51,6 @@
 					 ALT_TYPE_SPEC << ALT_TYPE_SHIFT	| \
 					 (facility) << ALT_DATA_SHIFT)
 
-#define ALT_LOWCORE			(ALT_CTX_EARLY << ALT_CTX_SHIFT		| \
-					 ALT_TYPE_LOWCORE << ALT_TYPE_SHIFT)
-
 #ifndef __ASSEMBLY__
 
 #include <linux/types.h>
diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index 42a092fa1029..60c887cdbaec 100644
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -10,6 +10,7 @@
 #define _ASM_S390_LOWCORE_H
 
 #include <linux/types.h>
+#include <asm/machine.h>
 #include <asm/ptrace.h>
 #include <asm/ctlreg.h>
 #include <asm/cpu.h>
@@ -222,7 +223,7 @@ static __always_inline struct lowcore *get_lowcore(void)
 
 	if (__is_defined(__DECOMPRESSOR))
 		return NULL;
-	asm(ALTERNATIVE("llilh %[lc],0", "llilh %[lc],%[alt]", ALT_LOWCORE)
+	asm(ALTERNATIVE("llilh %[lc],0", "llilh %[lc],%[alt]", ALT_FEATURE(MFEATURE_LOWCORE))
 	    : [lc] "=d" (lc)
 	    : [alt] "i" (LOWCORE_ALT_ADDRESS >> 16));
 	return lc;
@@ -240,13 +241,13 @@ static inline void set_prefix(__u32 address)
 .macro GET_LC reg
 	ALTERNATIVE "llilh	\reg,0",					\
 		__stringify(llilh	\reg, LOWCORE_ALT_ADDRESS >> 16),	\
-		ALT_LOWCORE
+		ALT_FEATURE(MFEATURE_LOWCORE)
 .endm
 
 .macro STMG_LC start, end, savearea
 	ALTERNATIVE "stmg	\start, \end, \savearea",				\
 		__stringify(stmg	\start, \end, LOWCORE_ALT_ADDRESS + \savearea),	\
-		ALT_LOWCORE
+		ALT_FEATURE(MFEATURE_LOWCORE)
 .endm
 
 #endif /* __ASSEMBLY__ */
diff --git a/arch/s390/include/asm/machine.h b/arch/s390/include/asm/machine.h
index bbe6c24bfc88..bc30384d396d 100644
--- a/arch/s390/include/asm/machine.h
+++ b/arch/s390/include/asm/machine.h
@@ -6,6 +6,10 @@
 #ifndef __ASM_S390_MACHINE_H
 #define __ASM_S390_MACHINE_H
 
+#include <linux/const.h>
+
+#define MFEATURE_LOWCORE	0
+
 #ifndef __ASSEMBLY__
 
 #include <linux/bitops.h>
@@ -72,5 +76,7 @@ static __always_inline bool machine_has_##name(void)				\
 	return test_machine_feature(feature);					\
 }
 
+DEFINE_MACHINE_HAS_FEATURE(relocated_lowcore, MFEATURE_LOWCORE)
+
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_S390_MACHINE_H */
diff --git a/arch/s390/kernel/abs_lowcore.c b/arch/s390/kernel/abs_lowcore.c
index 88f0b91d7a73..6252b7d115dd 100644
--- a/arch/s390/kernel/abs_lowcore.c
+++ b/arch/s390/kernel/abs_lowcore.c
@@ -5,7 +5,6 @@
 #include <asm/sections.h>
 
 unsigned long __bootdata_preserved(__abs_lowcore);
-int __bootdata_preserved(relocate_lowcore);
 
 int abs_lowcore_map(int cpu, struct lowcore *lc, bool alloc)
 {
diff --git a/arch/s390/kernel/alternative.c b/arch/s390/kernel/alternative.c
index d3839fc0543d..2f56649bbde8 100644
--- a/arch/s390/kernel/alternative.c
+++ b/arch/s390/kernel/alternative.c
@@ -33,9 +33,6 @@ void __apply_alternatives(struct alt_instr *start, struct alt_instr *end, unsign
 		case ALT_TYPE_SPEC:
 			replace = nobp_enabled();
 			break;
-		case ALT_TYPE_LOWCORE:
-			replace = have_relocated_lowcore();
-			break;
 		default:
 			replace = false;
 		}
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 4cc3408c4dac..c328e05b584c 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -29,6 +29,7 @@
 #include <asm/nmi.h>
 #include <asm/nospec-insn.h>
 #include <asm/lowcore.h>
+#include <asm/machine.h>
 
 _LPP_OFFSET	= __LC_LPP
 
@@ -44,7 +45,7 @@ _LPP_OFFSET	= __LC_LPP
 	ALTERNATIVE_2 "b \lpswe;nopr", \
 		".insn siy,0xeb0000000071,\address,0", ALT_FACILITY(193),		\
 		__stringify(.insn siy,0xeb0000000071,LOWCORE_ALT_ADDRESS+\address,0),	\
-		ALT_LOWCORE
+		ALT_FEATURE(MFEATURE_LOWCORE)
 	.endm
 
 	.macro MBEAR reg, lowcore
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index c9dd34461625..ab8816cf2f8b 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -54,6 +54,7 @@
 
 #include <asm/archrandom.h>
 #include <asm/boot_data.h>
+#include <asm/machine.h>
 #include <asm/ipl.h>
 #include <asm/facility.h>
 #include <asm/smp.h>
@@ -911,7 +912,7 @@ void __init setup_arch(char **cmdline_p)
 	if (!boot_earlyprintk)
 		boot_rb_foreach(print_rb_entry);
 
-	if (have_relocated_lowcore())
+	if (machine_has_relocated_lowcore())
 		pr_info("Lowcore relocated to 0x%px\n", get_lowcore());
 
 	log_component_list();