Commit 95d38fd0 authored by Christian Borntraeger's avatar Christian Borntraeger Committed by Gleb Natapov
Browse files

s390/kvm: Mark if a cpu is in SIE 



Lets track in a private bit if the sie control block is active.
We want to track this as closely as possible, so we also have to
instrument the interrupt and program check handler. Lets use the
existing HANDLE_SIE_INTERCEPT macro.

Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarGleb Natapov <gleb@redhat.com>
parent 0d0dafc1

arch/s390/include/asm/kvm_host.h

+4 −1
Original line number Diff line number Diff line
@@ -68,7 +68,10 @@ struct sca_block { 
struct kvm_s390_sie_block {

	atomic_t cpuflags;		/* 0x0000 */

	__u32	prefix;			/* 0x0004 */

	__u8	reserved8[32];		/* 0x0008 */

	__u8	reserved08[4];		/* 0x0008 */

#define PROG_IN_SIE (1<<0)

	__u32	prog0c;			/* 0x000c */

	__u8	reserved10[24];		/* 0x0010 */

	__u64	cputm;			/* 0x0028 */

	__u64	ckc;			/* 0x0030 */

	__u64	epoch;			/* 0x0038 */

arch/s390/kernel/asm-offsets.c

+2 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
#define ASM_OFFSETS_C



#include <linux/kbuild.h>

#include <linux/kvm_host.h>

#include <linux/sched.h>

#include <asm/cputime.h>

#include <asm/vdso.h>
@@ -161,6 +162,7 @@ int main(void) 
	DEFINE(__LC_PGM_TDB, offsetof(struct _lowcore, pgm_tdb));

	DEFINE(__THREAD_trap_tdb, offsetof(struct task_struct, thread.trap_tdb));

	DEFINE(__GMAP_ASCE, offsetof(struct gmap, asce));

	DEFINE(__SIE_PROG0C, offsetof(struct kvm_s390_sie_block, prog0c));

#endif /* CONFIG_32BIT */

	return 0;

}

arch/s390/kernel/entry64.S

+7 −3
Original line number Diff line number Diff line
@@ -84,7 +84,7 @@ _TIF_EXIT_SIE = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING) 
	.macro	HANDLE_SIE_INTERCEPT scratch,pgmcheck

#if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)

	tmhh	%r8,0x0001		# interrupting from user ?

	jnz	.+42

	jnz	.+52

	lgr	\scratch,%r9

	slg	\scratch,BASED(.Lsie_loop)

	clg	\scratch,BASED(.Lsie_length)
@@ -92,12 +92,14 @@ _TIF_EXIT_SIE = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING) 
	# Some program interrupts are suppressing (e.g. protection).

	# We must also check the instruction after SIE in that case.

	# do_protection_exception will rewind to rewind_pad

	jh	.+22

	jh	.+32

	.else

	jhe	.+22

	jhe	.+32

	.endif

	lg	%r9,BASED(.Lsie_loop)

	LPP	BASED(.Lhost_id)	# set host id

	lg	%r14,__SF_EMPTY(%r15)	# get control block pointer

	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE

#endif

	.endm
@@ -956,10 +958,12 @@ sie_loop: 
	lctlg	%c1,%c1,__GMAP_ASCE(%r14)	# load primary asce

sie_gmap:

	lg	%r14,__SF_EMPTY(%r15)		# get control block pointer

	oi	__SIE_PROG0C+3(%r14),1		# we are in SIE now

	LPP	__SF_EMPTY(%r15)		# set guest id

	sie	0(%r14)

sie_done:

	LPP	__SF_EMPTY+16(%r15)		# set host id

	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE

	lg	%r14,__LC_THREAD_INFO		# pointer thread_info struct

sie_exit:

	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce

CRA Git | Maintained and supported by SUSTech CRA and CCSE