Commit cf13f0ea authored by Heiko Carstens's avatar Heiko Carstens Committed by Linus Torvalds

[PATCH] kexec: s390 support

Add kexec support for s390 architecture.

From: Milton Miller <miltonm@bga.com>

- Fix passing of first argument to relocate_kernel assembly.
- Fix Kconfig description.
- Remove wrong comment and comments that describe obvious things.
- Allow only KEXEC_TYPE_DEFAULT as image type -> dump not supported.
Acked-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent fce0d574
......@@ -455,6 +455,14 @@ config NO_IDLE_HZ_INIT
The HZ timer is switched off in idle by default. That means the
HZ timer is already disabled at boot time.
config KEXEC
bool "kexec system call (EXPERIMENTAL)"
depends on EXPERIMENTAL
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
but is independent of hardware/microcode support.
endmenu
config PCMCIA
......
......@@ -25,6 +25,16 @@ obj-$(CONFIG_ARCH_S390X) += entry64.o reipl64.o
obj-$(CONFIG_VIRT_TIMER) += vtime.o
# Kexec part
S390_KEXEC_OBJS := machine_kexec.o crash.o
ifeq ($(CONFIG_ARCH_S390X),y)
S390_KEXEC_OBJS += relocate_kernel64.o
else
S390_KEXEC_OBJS += relocate_kernel.o
endif
obj-$(CONFIG_KEXEC) += $(S390_KEXEC_OBJS)
#
# This is just to get the dependencies...
#
......
......@@ -1441,3 +1441,11 @@ compat_sys_waitid_wrapper:
lgfr %r5,%r5 # int
llgtr %r6,%r6 # struct rusage_emu31 *
jg compat_sys_waitid
.globl compat_sys_kexec_load_wrapper
compat_sys_kexec_load_wrapper:
llgfr %r2,%r2 # unsigned long
llgfr %r3,%r3 # unsigned long
llgtr %r4,%r4 # struct kexec_segment *
llgfr %r5,%r5 # unsigned long
jg compat_sys_kexec_load
/*
* arch/s390/kernel/crash.c
*
* (C) Copyright IBM Corp. 2005
*
* Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
*
*/
#include <linux/threads.h>
#include <linux/kexec.h>
note_buf_t crash_notes[NR_CPUS];
void machine_crash_shutdown(void)
{
}
/*
* arch/s390/kernel/machine_kexec.c
*
* (C) Copyright IBM Corp. 2005
*
* Author(s): Rolf Adelsberger <adelsberger@de.ibm.com>
*
*/
/*
* s390_machine_kexec.c - handle the transition of Linux booting another kernel
* on the S390 architecture.
*/
#include <asm/cio.h>
#include <asm/setup.h>
#include <linux/device.h>
#include <linux/mm.h>
#include <linux/kexec.h>
#include <linux/delay.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/system.h>
static void kexec_halt_all_cpus(void *);
typedef void (*relocate_kernel_t) (kimage_entry_t *, unsigned long);
const extern unsigned char relocate_kernel[];
const extern unsigned long long relocate_kernel_len;
int
machine_kexec_prepare(struct kimage *image)
{
unsigned long reboot_code_buffer;
/* We don't support anything but the default image type for now. */
if (image->type != KEXEC_TYPE_DEFAULT)
return -EINVAL;
/* Get the destination where the assembler code should be copied to.*/
reboot_code_buffer = page_to_pfn(image->control_code_page)<<PAGE_SHIFT;
/* Then copy it */
memcpy((void *) reboot_code_buffer, relocate_kernel,
relocate_kernel_len);
return 0;
}
void
machine_kexec_cleanup(struct kimage *image)
{
}
void
machine_shutdown(void)
{
printk(KERN_INFO "kexec: machine_shutdown called\n");
}
NORET_TYPE void
machine_kexec(struct kimage *image)
{
clear_all_subchannels();
/* Disable lowcore protection */
ctl_clear_bit(0,28);
on_each_cpu(kexec_halt_all_cpus, image, 0, 0);
for(;;);
}
static void
kexec_halt_all_cpus(void *kernel_image)
{
static atomic_t cpuid = ATOMIC_INIT(-1);
int cpu;
struct kimage *image;
relocate_kernel_t data_mover;
if (atomic_compare_and_swap(-1, smp_processor_id(), &cpuid))
signal_processor(smp_processor_id(), sigp_stop);
/* Wait for all other cpus to enter stopped state */
for_each_online_cpu(cpu) {
if (cpu == smp_processor_id())
continue;
while(!smp_cpu_not_running(cpu))
cpu_relax();
}
image = (struct kimage *) kernel_image;
data_mover = (relocate_kernel_t)
(page_to_pfn(image->control_code_page) << PAGE_SHIFT);
/* Call the moving routine */
(*data_mover) (&image->head, image->start);
}
/*
* arch/s390/kernel/relocate_kernel.S
*
* (C) Copyright IBM Corp. 2005
*
* Author(s): Rolf Adelsberger <adelsberger@de.ibm.com>
*
*/
/*
* moves the new kernel to its destination...
* %r2 = pointer to first kimage_entry_t
* %r3 = start address - where to jump to after the job is done...
*
* %r5 will be used as temp. storage
* %r6 holds the destination address
* %r7 = PAGE_SIZE
* %r8 holds the source address
* %r9 = PAGE_SIZE
* %r10 is a page mask
*/
.text
.globl relocate_kernel
relocate_kernel:
basr %r13,0 #base address
.base:
spx zero64-.base(%r13) #absolute addressing mode
stnsm sys_msk-.base(%r13),0xf8 #disable DAT and IRQ (external)
lhi %r10,-1 #preparing the mask
sll %r10,12 #shift it such that it becomes 0xf000
.top:
lhi %r7,4096 #load PAGE_SIZE in r7
lhi %r9,4096 #load PAGE_SIZE in r9
l %r5,0(%r2) #read another word for indirection page
ahi %r2,4 #increment pointer
tml %r5,0x1 #is it a destination page?
je .indir_check #NO, goto "indir_check"
lr %r6,%r5 #r6 = r5
nr %r6,%r10 #mask it out and...
j .top #...next iteration
.indir_check:
tml %r5,0x2 #is it a indirection page?
je .done_test #NO, goto "done_test"
nr %r5,%r10 #YES, mask out,
lr %r2,%r5 #move it into the right register,
j .top #and read next...
.done_test:
tml %r5,0x4 #is it the done indicator?
je .source_test #NO! Well, then it should be the source indicator...
j .done #ok, lets finish it here...
.source_test:
tml %r5,0x8 #it should be a source indicator...
je .top #NO, ignore it...
lr %r8,%r5 #r8 = r5
nr %r8,%r10 #masking
0: mvcle %r6,%r8,0x0 #copy PAGE_SIZE bytes from r8 to r6 - pad with 0
jo 0b
j .top
.done:
sr %r0,%r0 #clear register r0
la %r4,load_psw-.base(%r13) #load psw-address into the register
o %r3,4(%r4) #or load address into psw
st %r3,4(%r4)
mvc 0(8,%r0),0(%r4) #copy psw to absolute address 0
sr %r1,%r1 #clear %r1
sr %r2,%r2 #clear %r2
sigp %r1,%r2,0x12 #set cpuid to zero
lpsw 0 #hopefully start new kernel...
.align 8
zero64:
.quad 0
load_psw:
.long 0x00080000,0x80000000
sys_msk:
.quad 0
relocate_kernel_end:
.globl relocate_kernel_len
relocate_kernel_len:
.quad relocate_kernel_end - relocate_kernel
/*
* arch/s390/kernel/relocate_kernel64.S
*
* (C) Copyright IBM Corp. 2005
*
* Author(s): Rolf Adelsberger <adelsberger@de.ibm.com>
*
*/
/*
* moves the new kernel to its destination...
* %r2 = pointer to first kimage_entry_t
* %r3 = start address - where to jump to after the job is done...
*
* %r5 will be used as temp. storage
* %r6 holds the destination address
* %r7 = PAGE_SIZE
* %r8 holds the source address
* %r9 = PAGE_SIZE
*
* 0xf000 is a page_mask
*/
.text
.globl relocate_kernel
relocate_kernel:
basr %r13,0 #base address
.base:
spx zero64-.base(%r13) #absolute addressing mode
stnsm sys_msk-.base(%r13),0xf8 #disable DAT and IRQ (external)
.top:
lghi %r7,4096 #load PAGE_SIZE in r7
lghi %r9,4096 #load PAGE_SIZE in r9
lg %r5,0(%r2) #read another word for indirection page
aghi %r2,8 #increment pointer
tml %r5,0x1 #is it a destination page?
je .indir_check #NO, goto "indir_check"
lgr %r6,%r5 #r6 = r5
nill %r6,0xf000 #mask it out and...
j .top #...next iteration
.indir_check:
tml %r5,0x2 #is it a indirection page?
je .done_test #NO, goto "done_test"
nill %r5,0xf000 #YES, mask out,
lgr %r2,%r5 #move it into the right register,
j .top #and read next...
.done_test:
tml %r5,0x4 #is it the done indicator?
je .source_test #NO! Well, then it should be the source indicator...
j .done #ok, lets finish it here...
.source_test:
tml %r5,0x8 #it should be a source indicator...
je .top #NO, ignore it...
lgr %r8,%r5 #r8 = r5
nill %r8,0xf000 #masking
0: mvcle %r6,%r8,0x0 #copy PAGE_SIZE bytes from r8 to r6 - pad with 0
jo 0b
j .top
.done:
sgr %r0,%r0 #clear register r0
la %r4,load_psw-.base(%r13) #load psw-address into the register
o %r3,4(%r4) #or load address into psw
st %r3,4(%r4)
mvc 0(8,%r0),0(%r4) #copy psw to absolute address 0
sam31 #31 bit mode
sr %r1,%r1 #erase register r1
sr %r2,%r2 #erase register r2
sigp %r1,%r2,0x12 #set cpuid to zero
lpsw 0 #hopefully start new kernel...
.align 8
zero64:
.quad 0
load_psw:
.long 0x00080000,0x80000000
sys_msk:
.quad 0
relocate_kernel_end:
.globl relocate_kernel_len
relocate_kernel_len:
.quad relocate_kernel_end - relocate_kernel
......@@ -285,7 +285,7 @@ SYSCALL(sys_mq_timedsend,sys_mq_timedsend,compat_sys_mq_timedsend_wrapper)
SYSCALL(sys_mq_timedreceive,sys_mq_timedreceive,compat_sys_mq_timedreceive_wrapper)
SYSCALL(sys_mq_notify,sys_mq_notify,compat_sys_mq_notify_wrapper) /* 275 */
SYSCALL(sys_mq_getsetattr,sys_mq_getsetattr,compat_sys_mq_getsetattr_wrapper)
NI_SYSCALL /* reserved for kexec */
SYSCALL(sys_kexec_load,sys_kexec_load,compat_sys_kexec_load_wrapper)
SYSCALL(sys_add_key,sys_add_key,compat_sys_add_key_wrapper)
SYSCALL(sys_request_key,sys_request_key,compat_sys_request_key_wrapper)
SYSCALL(sys_keyctl,sys_keyctl,compat_sys_keyctl) /* 280 */
......
/*
* include/asm-s390/kexec.h
*
* (C) Copyright IBM Corp. 2005
*
* Author(s): Rolf Adelsberger <adelsberger@de.ibm.com>
*
*/
#ifndef _S390_KEXEC_H
#define _S390_KEXEC_H
#include <asm/page.h>
#include <asm/processor.h>
/*
* KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
* I.e. Maximum page that is mapped directly into kernel memory,
* and kmap is not required.
*/
/* Maximum physical address we can use pages from */
#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
/* Maximum address we can reach in physical address mode */
#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
/* Maximum address we can use for the control pages */
/* Not more than 2GB */
#define KEXEC_CONTROL_MEMORY_LIMIT (1<<31)
/* Allocate one page for the pdp and the second for the code */
#define KEXEC_CONTROL_CODE_SIZE 4096
/* The native architecture */
#define KEXEC_ARCH KEXEC_ARCH_S390
#define MAX_NOTE_BYTES 1024
typedef u32 note_buf_t[MAX_NOTE_BYTES/4];
extern note_buf_t crash_notes[];
#endif /*_S390_KEXEC_H */
......@@ -269,7 +269,7 @@
#define __NR_mq_timedreceive 274
#define __NR_mq_notify 275
#define __NR_mq_getsetattr 276
/* Number 277 is reserved for new sys_kexec_load */
#define __NR_kexec_load 277
#define __NR_add_key 278
#define __NR_request_key 279
#define __NR_keyctl 280
......
......@@ -114,6 +114,7 @@ extern struct kimage *kexec_image;
#define KEXEC_ARCH_PPC (20 << 16)
#define KEXEC_ARCH_PPC64 (21 << 16)
#define KEXEC_ARCH_IA_64 (50 << 16)
#define KEXEC_ARCH_S390 (22 << 16)
#define KEXEC_FLAGS (KEXEC_ON_CRASH) /* List of defined/legal kexec flags */
......
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