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s390/kvm: integrate HANDLE_SIE_INTERCEPT into cleanup_critical

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Currently there are two mechanisms to deal with cleanup work due to
interrupts. The HANDLE_SIE_INTERCEPT macro is used to undo the changes
required to enter SIE in sie64a. If the SIE instruction causes a program
check, or an asynchronous interrupt is received the HANDLE_SIE_INTERCEPT
code forwards the program execution to sie_exit.

All the other critical sections in entry.S are handled by the code in
cleanup_critical that is called by the SWITCH_ASYNC macro.

Move the sie64a function to the beginning of the critical section and
add the code from HANDLE_SIE_INTERCEPT to cleanup_critical. Add a special
case for the sie64a cleanup to the program check handler.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2015-06-22 17:26:40 +02:00
parent dcd2a9aaa0
commit d0fc41071a
1 changed files with 123 additions and 118 deletions
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241
arch/s390/kernel/entry.S
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@ -75,31 +75,6 @@ _PIF_WORK = (_PIF_PER_TRAP)
#endif #endif
.endm .endm
.macro LPP newpp
#if IS_ENABLED(CONFIG_KVM)
tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_LPP
jz .+8
.insn s,0xb2800000,\newpp
#endif
.endm
.macro HANDLE_SIE_INTERCEPT scratch,reason
#if IS_ENABLED(CONFIG_KVM)
tmhh %r8,0x0001 # interrupting from user ?
jnz .+62
lgr \scratch,%r9
slg \scratch,BASED(.Lsie_critical)
clg \scratch,BASED(.Lsie_critical_length)
jhe .+42
lg %r14,__SF_EMPTY(%r15) # get control block pointer
LPP __SF_EMPTY+16(%r15) # set host id
ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
larl %r9,sie_exit # skip forward to sie_exit
mvi __SF_EMPTY+31(%r15),\reason # set exit reason
#endif
.endm
.macro CHECK_STACK stacksize,savearea .macro CHECK_STACK stacksize,savearea
#ifdef CONFIG_CHECK_STACK #ifdef CONFIG_CHECK_STACK
tml %r15,\stacksize - CONFIG_STACK_GUARD tml %r15,\stacksize - CONFIG_STACK_GUARD
@ -192,6 +167,70 @@ ENTRY(__switch_to)
br %r14 br %r14
.L__critical_start: .L__critical_start:
#if IS_ENABLED(CONFIG_KVM)
/*
* sie64a calling convention:
* %r2 pointer to sie control block
* %r3 guest register save area
*/
ENTRY(sie64a)
stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
stg %r2,__SF_EMPTY(%r15) # save control block pointer
stg %r3,__SF_EMPTY+8(%r15) # save guest register save area
xc __SF_EMPTY+16(16,%r15),__SF_EMPTY+16(%r15) # host id & reason
tm __LC_CPU_FLAGS+7,_CIF_FPU # load guest fp/vx registers ?
jno .Lsie_load_guest_gprs
lg %r12,__LC_THREAD_INFO # load fp/vx regs save area
brasl %r14,load_fpu_regs # load guest fp/vx regs
.Lsie_load_guest_gprs:
lmg %r0,%r13,0(%r3) # load guest gprs 0-13
lg %r14,__LC_GMAP # get gmap pointer
ltgr %r14,%r14
jz .Lsie_gmap
lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce
.Lsie_gmap:
lg %r14,__SF_EMPTY(%r15) # get control block pointer
oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now
tm __SIE_PROG20+3(%r14),3 # last exit...
jnz .Lsie_skip
tm __LC_CPU_FLAGS+7,_CIF_FPU
jo .Lsie_skip # exit if fp/vx regs changed
tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_LPP
jz .Lsie_enter
.insn s,0xb2800000,__SF_EMPTY(%r15) # set guest id
.Lsie_enter:
sie 0(%r14)
tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_LPP
jz .Lsie_skip
.insn s,0xb2800000,__SF_EMPTY+16(%r15)# set host id
.Lsie_skip:
ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
.Lsie_done:
# some program checks are suppressing. C code (e.g. do_protection_exception)
# will rewind the PSW by the ILC, which is 4 bytes in case of SIE. Other
# instructions between sie64a and .Lsie_done should not cause program
# interrupts. So lets use a nop (47 00 00 00) as a landing pad.
# See also .Lcleanup_sie
.Lrewind_pad:
nop 0
.globl sie_exit
sie_exit:
lg %r14,__SF_EMPTY+8(%r15) # load guest register save area
stmg %r0,%r13,0(%r14) # save guest gprs 0-13
lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers
lg %r2,__SF_EMPTY+24(%r15) # return exit reason code
br %r14
.Lsie_fault:
lghi %r14,-EFAULT
stg %r14,__SF_EMPTY+24(%r15) # set exit reason code
j sie_exit
EX_TABLE(.Lrewind_pad,.Lsie_fault)
EX_TABLE(sie_exit,.Lsie_fault)
#endif
/* /*
* SVC interrupt handler routine. System calls are synchronous events and * SVC interrupt handler routine. System calls are synchronous events and
* are executed with interrupts enabled. * are executed with interrupts enabled.
@ -411,26 +450,33 @@ ENTRY(pgm_check_handler)
lg %r12,__LC_THREAD_INFO lg %r12,__LC_THREAD_INFO
larl %r13,cleanup_critical larl %r13,cleanup_critical
lmg %r8,%r9,__LC_PGM_OLD_PSW lmg %r8,%r9,__LC_PGM_OLD_PSW
HANDLE_SIE_INTERCEPT %r14,1
tmhh %r8,0x0001 # test problem state bit tmhh %r8,0x0001 # test problem state bit
jnz 1f # -> fault in user space jnz 2f # -> fault in user space
tmhh %r8,0x4000 # PER bit set in old PSW ? #if IS_ENABLED(CONFIG_KVM)
jnz 0f # -> enabled, can't be a double fault # cleanup critical section for sie64a
lgr %r14,%r9
slg %r14,BASED(.Lsie_critical_start)
clg %r14,BASED(.Lsie_critical_length)
jhe 0f
brasl %r14,.Lcleanup_sie
#endif
0: tmhh %r8,0x4000 # PER bit set in old PSW ?
jnz 1f # -> enabled, can't be a double fault
tm __LC_PGM_ILC+3,0x80 # check for per exception tm __LC_PGM_ILC+3,0x80 # check for per exception
jnz .Lpgm_svcper # -> single stepped svc jnz .Lpgm_svcper # -> single stepped svc
0: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC 1: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
j 2f j 3f
1: UPDATE_VTIME %r14,__LC_SYNC_ENTER_TIMER 2: UPDATE_VTIME %r14,__LC_SYNC_ENTER_TIMER
LAST_BREAK %r14 LAST_BREAK %r14
lg %r15,__LC_KERNEL_STACK lg %r15,__LC_KERNEL_STACK
lg %r14,__TI_task(%r12) lg %r14,__TI_task(%r12)
aghi %r14,__TASK_thread # pointer to thread_struct aghi %r14,__TASK_thread # pointer to thread_struct
lghi %r13,__LC_PGM_TDB lghi %r13,__LC_PGM_TDB
tm __LC_PGM_ILC+2,0x02 # check for transaction abort tm __LC_PGM_ILC+2,0x02 # check for transaction abort
jz 2f jz 3f
mvc __THREAD_trap_tdb(256,%r14),0(%r13) mvc __THREAD_trap_tdb(256,%r14),0(%r13)
2: la %r11,STACK_FRAME_OVERHEAD(%r15) 3: la %r11,STACK_FRAME_OVERHEAD(%r15)
stmg %r0,%r7,__PT_R0(%r11) stmg %r0,%r7,__PT_R0(%r11)
mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
stmg %r8,%r9,__PT_PSW(%r11) stmg %r8,%r9,__PT_PSW(%r11)
@ -439,14 +485,14 @@ ENTRY(pgm_check_handler)
xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11) xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
stg %r10,__PT_ARGS(%r11) stg %r10,__PT_ARGS(%r11)
tm __LC_PGM_ILC+3,0x80 # check for per exception tm __LC_PGM_ILC+3,0x80 # check for per exception
jz 0f jz 4f
tmhh %r8,0x0001 # kernel per event ? tmhh %r8,0x0001 # kernel per event ?
jz .Lpgm_kprobe jz .Lpgm_kprobe
oi __PT_FLAGS+7(%r11),_PIF_PER_TRAP oi __PT_FLAGS+7(%r11),_PIF_PER_TRAP
mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS
mvc __THREAD_per_cause(2,%r14),__LC_PER_CODE mvc __THREAD_per_cause(2,%r14),__LC_PER_CODE
mvc __THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID mvc __THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID
0: REENABLE_IRQS 4: REENABLE_IRQS
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
larl %r1,pgm_check_table larl %r1,pgm_check_table
llgh %r10,__PT_INT_CODE+2(%r11) llgh %r10,__PT_INT_CODE+2(%r11)
@ -489,7 +535,6 @@ ENTRY(io_int_handler)
lg %r12,__LC_THREAD_INFO lg %r12,__LC_THREAD_INFO
larl %r13,cleanup_critical larl %r13,cleanup_critical
lmg %r8,%r9,__LC_IO_OLD_PSW lmg %r8,%r9,__LC_IO_OLD_PSW
HANDLE_SIE_INTERCEPT %r14,2
SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
tmhh %r8,0x0001 # interrupting from user? tmhh %r8,0x0001 # interrupting from user?
jz .Lio_skip jz .Lio_skip
@ -667,7 +712,6 @@ ENTRY(ext_int_handler)
lg %r12,__LC_THREAD_INFO lg %r12,__LC_THREAD_INFO
larl %r13,cleanup_critical larl %r13,cleanup_critical
lmg %r8,%r9,__LC_EXT_OLD_PSW lmg %r8,%r9,__LC_EXT_OLD_PSW
HANDLE_SIE_INTERCEPT %r14,3
SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
tmhh %r8,0x0001 # interrupting from user ? tmhh %r8,0x0001 # interrupting from user ?
jz .Lext_skip jz .Lext_skip
@ -832,7 +876,6 @@ ENTRY(mcck_int_handler)
lg %r12,__LC_THREAD_INFO lg %r12,__LC_THREAD_INFO
larl %r13,cleanup_critical larl %r13,cleanup_critical
lmg %r8,%r9,__LC_MCK_OLD_PSW lmg %r8,%r9,__LC_MCK_OLD_PSW
HANDLE_SIE_INTERCEPT %r14,4
tm __LC_MCCK_CODE,0x80 # system damage? tm __LC_MCCK_CODE,0x80 # system damage?
jo .Lmcck_panic # yes -> rest of mcck code invalid jo .Lmcck_panic # yes -> rest of mcck code invalid
lghi %r14,__LC_CPU_TIMER_SAVE_AREA lghi %r14,__LC_CPU_TIMER_SAVE_AREA
@ -947,26 +990,13 @@ stack_overflow:
jg kernel_stack_overflow jg kernel_stack_overflow
#endif #endif
.align 8
.Lcleanup_table:
.quad system_call
.quad .Lsysc_do_svc
.quad .Lsysc_tif
.quad .Lsysc_restore
.quad .Lsysc_done
.quad .Lio_tif
.quad .Lio_restore
.quad .Lio_done
.quad psw_idle
.quad .Lpsw_idle_end
.quad save_fpu_regs
.quad .Lsave_fpu_regs_end
.quad load_fpu_regs
.quad .Lload_fpu_regs_end
.quad __ctl_set_vx
.quad .L__ctl_set_vx_end
cleanup_critical: cleanup_critical:
#if IS_ENABLED(CONFIG_KVM)
clg %r9,BASED(.Lcleanup_table_sie) # .Lsie_gmap
jl 0f
clg %r9,BASED(.Lcleanup_table_sie+8)# .Lsie_done
jl .Lcleanup_sie
#endif
clg %r9,BASED(.Lcleanup_table) # system_call clg %r9,BASED(.Lcleanup_table) # system_call
jl 0f jl 0f
clg %r9,BASED(.Lcleanup_table+8) # .Lsysc_do_svc clg %r9,BASED(.Lcleanup_table+8) # .Lsysc_do_svc
@ -1001,6 +1031,40 @@ cleanup_critical:
jl .Lcleanup___ctl_set_vx jl .Lcleanup___ctl_set_vx
0: br %r14 0: br %r14
.align 8
.Lcleanup_table:
.quad system_call
.quad .Lsysc_do_svc
.quad .Lsysc_tif
.quad .Lsysc_restore
.quad .Lsysc_done
.quad .Lio_tif
.quad .Lio_restore
.quad .Lio_done
.quad psw_idle
.quad .Lpsw_idle_end
.quad save_fpu_regs
.quad .Lsave_fpu_regs_end
.quad load_fpu_regs
.quad .Lload_fpu_regs_end
.quad __ctl_set_vx
.quad .L__ctl_set_vx_end
#if IS_ENABLED(CONFIG_KVM)
.Lcleanup_table_sie:
.quad .Lsie_gmap
.quad .Lsie_done
.Lcleanup_sie:
lg %r9,__SF_EMPTY(%r15) # get control block pointer
tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_LPP
jz 0f
.insn s,0xb2800000,__SF_EMPTY+16(%r15)# set host id
0: ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE
lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
larl %r9,sie_exit # skip forward to sie_exit
br %r14
#endif
.Lcleanup_system_call: .Lcleanup_system_call:
# check if stpt has been executed # check if stpt has been executed
@ -1274,70 +1338,11 @@ cleanup_critical:
.quad .L__critical_start .quad .L__critical_start
.Lcritical_length: .Lcritical_length:
.quad .L__critical_end - .L__critical_start .quad .L__critical_end - .L__critical_start
#if IS_ENABLED(CONFIG_KVM) #if IS_ENABLED(CONFIG_KVM)
/* .Lsie_critical_start:
* sie64a calling convention:
* %r2 pointer to sie control block
* %r3 guest register save area
*/
ENTRY(sie64a)
stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
stg %r2,__SF_EMPTY(%r15) # save control block pointer
stg %r3,__SF_EMPTY+8(%r15) # save guest register save area
xc __SF_EMPTY+16(16,%r15),__SF_EMPTY+16(%r15) # host id & reason
tm __LC_CPU_FLAGS+7,_CIF_FPU # load guest fp/vx registers ?
jno .Lsie_load_guest_gprs
lg %r12,__LC_THREAD_INFO # load fp/vx regs save area
brasl %r14,load_fpu_regs # load guest fp/vx regs
.Lsie_load_guest_gprs:
lmg %r0,%r13,0(%r3) # load guest gprs 0-13
lg %r14,__LC_GMAP # get gmap pointer
ltgr %r14,%r14
jz .Lsie_gmap
lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce
.Lsie_gmap:
lg %r14,__SF_EMPTY(%r15) # get control block pointer
oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now
tm __SIE_PROG20+3(%r14),3 # last exit...
jnz .Lsie_skip
tm __LC_CPU_FLAGS+7,_CIF_FPU
jo .Lsie_skip # exit if fp/vx regs changed
LPP __SF_EMPTY(%r15) # set guest id
sie 0(%r14)
LPP __SF_EMPTY+16(%r15) # set host id
.Lsie_skip:
ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
.Lsie_done:
# some program checks are suppressing. C code (e.g. do_protection_exception)
# will rewind the PSW by the ILC, which is 4 bytes in case of SIE. Other
# instructions between sie64a and .Lsie_done should not cause program
# interrupts. So lets use a nop (47 00 00 00) as a landing pad.
# See also HANDLE_SIE_INTERCEPT
.Lrewind_pad:
nop 0
.globl sie_exit
sie_exit:
lg %r14,__SF_EMPTY+8(%r15) # load guest register save area
stmg %r0,%r13,0(%r14) # save guest gprs 0-13
lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers
lg %r2,__SF_EMPTY+24(%r15) # return exit reason code
br %r14
.Lsie_fault:
lghi %r14,-EFAULT
stg %r14,__SF_EMPTY+24(%r15) # set exit reason code
j sie_exit
.align 8
.Lsie_critical:
.quad .Lsie_gmap .quad .Lsie_gmap
.Lsie_critical_length: .Lsie_critical_length:
.quad .Lsie_done - .Lsie_gmap .quad .Lsie_done - .Lsie_gmap
EX_TABLE(.Lrewind_pad,.Lsie_fault)
EX_TABLE(sie_exit,.Lsie_fault)
#endif #endif
.section .rodata, "a" .section .rodata, "a"