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kernel-ark/arch/s390/kernel/swsusp.S
Martin Schwidefsky 88d6425378 s390/hibernate: fix save and restore of vector registers 
The swsusp_arch_suspend()/swsusp_arch_resume() functions currently only
save and restore the floating point registers. If the task that started
the hibernation process is using vector registers they can get lost.
To fix this just call save_fpu_regs in swsusp_arch_suspend(), the restore
will happen automatically on return to user space.

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-09-17 13:43:41 +02:00

286 lines
6.6 KiB
ArmAsm
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/*
* S390 64-bit swsusp implementation
*
* Copyright IBM Corp. 2009
*
* Author(s): Hans-Joachim Picht <hans@linux.vnet.ibm.com>
* Michael Holzheu <holzheu@linux.vnet.ibm.com>
*/
#include <linux/linkage.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm/sigp.h>
/*
* Save register context in absolute 0 lowcore and call swsusp_save() to
* create in-memory kernel image. The context is saved in the designated
* "store status" memory locations (see POP).
* We return from this function twice. The first time during the suspend to
* disk process. The second time via the swsusp_arch_resume() function
* (see below) in the resume process.
* This function runs with disabled interrupts.
*/
.section .text
ENTRY(swsusp_arch_suspend)
stmg %r6,%r15,__SF_GPRS(%r15)
lgr %r1,%r15
aghi %r15,-STACK_FRAME_OVERHEAD
stg %r1,__SF_BACKCHAIN(%r15)
/* Store FPU registers */
brasl %r14,save_fpu_regs
/* Deactivate DAT */
stnsm __SF_EMPTY(%r15),0xfb
/* Store prefix register on stack */
stpx __SF_EMPTY(%r15)
/* Save prefix register contents for lowcore copy */
llgf %r10,__SF_EMPTY(%r15)
/* Get pointer to save area */
lghi %r1,0x1000
/* Save CPU address */
stap __LC_EXT_CPU_ADDR(%r0)
/* Store registers */
mvc 0x318(4,%r1),__SF_EMPTY(%r15) /* move prefix to lowcore */
stam %a0,%a15,0x340(%r1) /* store access registers */
stctg %c0,%c15,0x380(%r1) /* store control registers */
stmg %r0,%r15,0x280(%r1) /* store general registers */
stpt 0x328(%r1) /* store timer */
stck __SF_EMPTY(%r15) /* store clock */
stckc 0x330(%r1) /* store clock comparator */
/* Update cputime accounting before going to sleep */
lg %r0,__LC_LAST_UPDATE_TIMER
slg %r0,0x328(%r1)
alg %r0,__LC_SYSTEM_TIMER
stg %r0,__LC_SYSTEM_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),0x328(%r1)
lg %r0,__LC_LAST_UPDATE_CLOCK
slg %r0,__SF_EMPTY(%r15)
alg %r0,__LC_STEAL_TIMER
stg %r0,__LC_STEAL_TIMER
mvc __LC_LAST_UPDATE_CLOCK(8),__SF_EMPTY(%r15)
/* Activate DAT */
stosm __SF_EMPTY(%r15),0x04
/* Set prefix page to zero */
xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
spx __SF_EMPTY(%r15)
/* Save absolute zero pages */
larl %r2,suspend_zero_pages
lg %r2,0(%r2)
lghi %r4,0
lghi %r3,2*PAGE_SIZE
lghi %r5,2*PAGE_SIZE
1: mvcle %r2,%r4,0
jo 1b
/* Copy lowcore to absolute zero lowcore */
lghi %r2,0
lgr %r4,%r10
lghi %r3,2*PAGE_SIZE
lghi %r5,2*PAGE_SIZE
1: mvcle %r2,%r4,0
jo 1b
/* Save image */
brasl %r14,swsusp_save
/* Restore prefix register and return */
lghi %r1,0x1000
spx 0x318(%r1)
lmg %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
lghi %r2,0
br %r14
/*
* Restore saved memory image to correct place and restore register context.
* Then we return to the function that called swsusp_arch_suspend().
* swsusp_arch_resume() runs with disabled interrupts.
*/
ENTRY(swsusp_arch_resume)
stmg %r6,%r15,__SF_GPRS(%r15)
lgr %r1,%r15
aghi %r15,-STACK_FRAME_OVERHEAD
stg %r1,__SF_BACKCHAIN(%r15)
/* Make all free pages stable */
lghi %r2,1
brasl %r14,arch_set_page_states
/* Deactivate DAT */
stnsm __SF_EMPTY(%r15),0xfb
/* Set prefix page to zero */
xc __SF_EMPTY(4,%r15),__SF_EMPTY(%r15)
spx __SF_EMPTY(%r15)
/* Restore saved image */
larl %r1,restore_pblist
lg %r1,0(%r1)
ltgr %r1,%r1
jz 2f
0:
lg %r2,8(%r1)
lg %r4,0(%r1)
iske %r0,%r4
lghi %r3,PAGE_SIZE
lghi %r5,PAGE_SIZE
1:
mvcle %r2,%r4,0
jo 1b
lg %r2,8(%r1)
sske %r0,%r2
lg %r1,16(%r1)
ltgr %r1,%r1
jnz 0b
2:
ptlb /* flush tlb */
/* Reset System */
larl %r1,restart_entry
larl %r2,.Lrestart_diag308_psw
og %r1,0(%r2)
stg %r1,0(%r0)
larl %r1,.Lnew_pgm_check_psw
epsw %r2,%r3
stm %r2,%r3,0(%r1)
mvc __LC_PGM_NEW_PSW(16,%r0),0(%r1)
lghi %r0,0
diag %r0,%r0,0x308
restart_entry:
lhi %r1,1
sigp %r1,%r0,SIGP_SET_ARCHITECTURE
sam64
#ifdef CONFIG_SMP
larl %r1,smp_cpu_mt_shift
icm %r1,15,0(%r1)
jz smt_done
llgfr %r1,%r1
smt_loop:
sigp %r1,%r0,SIGP_SET_MULTI_THREADING
brc 8,smt_done /* accepted */
brc 2,smt_loop /* busy, try again */
smt_done:
#endif
larl %r1,.Lnew_pgm_check_psw
lpswe 0(%r1)
pgm_check_entry:
/* Switch to original suspend CPU */
larl %r1,.Lresume_cpu /* Resume CPU address: r2 */
stap 0(%r1)
llgh %r2,0(%r1)
llgh %r1,__LC_EXT_CPU_ADDR(%r0) /* Suspend CPU address: r1 */
cgr %r1,%r2
je restore_registers /* r1 = r2 -> nothing to do */
larl %r4,.Lrestart_suspend_psw /* Set new restart PSW */
mvc __LC_RST_NEW_PSW(16,%r0),0(%r4)
3:
sigp %r9,%r1,SIGP_INITIAL_CPU_RESET /* sigp initial cpu reset */
brc 8,4f /* accepted */
brc 2,3b /* busy, try again */
/* Suspend CPU not available -> panic */
larl %r15,init_thread_union
ahi %r15,1<<(PAGE_SHIFT+THREAD_ORDER)
larl %r2,.Lpanic_string
larl %r3,_sclp_print_early
lghi %r1,0
sam31
sigp %r1,%r0,SIGP_SET_ARCHITECTURE
basr %r14,%r3
larl %r3,.Ldisabled_wait_31
lpsw 0(%r3)
4:
/* Switch to suspend CPU */
sigp %r9,%r1,SIGP_RESTART /* sigp restart to suspend CPU */
brc 2,4b /* busy, try again */
5:
sigp %r9,%r2,SIGP_STOP /* sigp stop to current resume CPU */
brc 2,5b /* busy, try again */
6: j 6b
restart_suspend:
larl %r1,.Lresume_cpu
llgh %r2,0(%r1)
7:
sigp %r9,%r2,SIGP_SENSE /* sigp sense, wait for resume CPU */
brc 8,7b /* accepted, status 0, still running */
brc 2,7b /* busy, try again */
tmll %r9,0x40 /* Test if resume CPU is stopped */
jz 7b
restore_registers:
/* Restore registers */
lghi %r13,0x1000 /* %r1 = pointer to save area */
/* Ignore time spent in suspended state. */
llgf %r1,0x318(%r13)
stck __LC_LAST_UPDATE_CLOCK(%r1)
spt 0x328(%r13) /* reprogram timer */
//sckc 0x330(%r13) /* set clock comparator */
lctlg %c0,%c15,0x380(%r13) /* load control registers */
lam %a0,%a15,0x340(%r13) /* load access registers */
/* Load old stack */
lg %r15,0x2f8(%r13)
/* Save prefix register */
mvc __SF_EMPTY(4,%r15),0x318(%r13)
/* Restore absolute zero pages */
lghi %r2,0
larl %r4,suspend_zero_pages
lg %r4,0(%r4)
lghi %r3,2*PAGE_SIZE
lghi %r5,2*PAGE_SIZE
1: mvcle %r2,%r4,0
jo 1b
/* Restore prefix register */
spx __SF_EMPTY(%r15)
/* Activate DAT */
stosm __SF_EMPTY(%r15),0x04
/* Make all free pages unstable */
lghi %r2,0
brasl %r14,arch_set_page_states
/* Call arch specific early resume code */
brasl %r14,s390_early_resume
/* Return 0 */
lmg %r6,%r15,STACK_FRAME_OVERHEAD + __SF_GPRS(%r15)
lghi %r2,0
br %r14
.section .data..nosave,"aw",@progbits
.align 8
.Ldisabled_wait_31:
.long 0x000a0000,0x00000000
.Lpanic_string:
.asciz "Resume not possible because suspend CPU is no longer available"
.align 8
.Lrestart_diag308_psw:
.long 0x00080000,0x80000000
.Lrestart_suspend_psw:
.quad 0x0000000180000000,restart_suspend
.Lnew_pgm_check_psw:
.quad 0,pgm_check_entry
.Lresume_cpu:
.byte 0,0
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