Commit 4c89eb87 authored by Heiko Carstens's avatar Heiko Carstens
Browse files

s390/pfault: cleanup inline assemblies 



Cleanup the pfault inline assemblies:
- Use symbolic names for operands
- Add extra linebreaks, and whitespace to improve readability

In addition, change __pfault_init() to return -EOPNOTSUPP in case of
an exception, and don't return a made up valid diag 258 return value
(aka "8").
This allows to simplify the inline assembly, and makes debugging
easier, in case something is broken.

Reviewed-by: default avatarSven Schnelle <svens@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent 28254f36

arch/s390/include/asm/pfault.h

+3 −1
Original line number Diff line number Diff line
@@ -5,6 +5,8 @@ 
#ifndef _ASM_S390_PFAULT_H

#define _ASM_S390_PFAULT_H



#include <linux/errno.h>



int __pfault_init(void);

void __pfault_fini(void);
@@ -12,7 +14,7 @@ static inline int pfault_init(void) 
{

	if (IS_ENABLED(CONFIG_PFAULT))

		return __pfault_init();

	return -1;

	return -EOPNOTSUPP;

}



static inline void pfault_fini(void)

arch/s390/mm/pfault.c

+14 −14
Original line number Diff line number Diff line
@@ -51,19 +51,18 @@ static struct pfault_refbk pfault_init_refbk = { 


int __pfault_init(void)

{

        int rc;

	int rc = -EOPNOTSUPP;



	if (pfault_disable)

		return -1;

		return rc;

	diag_stat_inc(DIAG_STAT_X258);

	asm volatile(

		"	diag	%1,%0,0x258\n"

		"0:	j	2f\n"

		"1:	la	%0,8\n"

		"2:\n"

		EX_TABLE(0b,1b)

		: "=d" (rc)

		: "a" (&pfault_init_refbk), "m" (pfault_init_refbk) : "cc");

		"	diag	%[refbk],%[rc],0x258\n"

		"0:	nopr	%%r7\n"

		EX_TABLE(0b, 0b)

		: [rc] "+d" (rc)

		: [refbk] "a" (&pfault_init_refbk), "m" (pfault_init_refbk)

		: "cc");

	return rc;

}
@@ -76,15 +75,16 @@ static struct pfault_refbk pfault_fini_refbk = { 


void __pfault_fini(void)

{



	if (pfault_disable)

		return;

	diag_stat_inc(DIAG_STAT_X258);

	asm volatile(

		"	diag	%0,0,0x258\n"

		"	diag	%[refbk],0,0x258\n"

		"0:	nopr	%%r7\n"

		EX_TABLE(0b, 0b)

		: : "a" (&pfault_fini_refbk), "m" (pfault_fini_refbk) : "cc");

		:

		: [refbk] "a" (&pfault_fini_refbk), "m" (pfault_fini_refbk)

		: "cc");

}



static DEFINE_SPINLOCK(pfault_lock);