Commit 60a0c68d authored by Michael Holzheu's avatar Michael Holzheu Committed by Martin Schwidefsky
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[S390] kdump backend code



This patch provides the architecture specific part of the s390 kdump
support.
Signed-off-by: default avatarMichael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 7f0bf656
......@@ -569,6 +569,16 @@ config KEXEC
current kernel, and to start another kernel. It is like a reboot
but is independent of hardware/microcode support.
config CRASH_DUMP
bool "kernel crash dumps"
depends on 64BIT
help
Generate crash dump after being started by kexec.
Crash dump kernels are loaded in the main kernel with kexec-tools
into a specially reserved region and then later executed after
a crash by kdump/kexec.
For more details see Documentation/kdump/kdump.txt
config ZFCPDUMP
def_bool n
prompt "zfcpdump support"
......
......@@ -168,5 +168,6 @@ enum diag308_rc {
extern int diag308(unsigned long subcode, void *addr);
extern void diag308_reset(void);
extern void store_status(void);
#endif /* _ASM_S390_IPL_H */
......@@ -30,6 +30,9 @@
/* Not more than 2GB */
#define KEXEC_CONTROL_MEMORY_LIMIT (1UL<<31)
/* Maximum address we can use for the crash control pages */
#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT (-1UL)
/* Allocate one page for the pdp and the second for the code */
#define KEXEC_CONTROL_PAGE_SIZE 4096
......
......@@ -17,5 +17,5 @@ struct reset_call {
extern void register_reset_call(struct reset_call *reset);
extern void unregister_reset_call(struct reset_call *reset);
extern void s390_reset_system(void);
extern void s390_reset_system(void (*func)(void *), void *data);
#endif /* _ASM_S390_RESET_H */
......@@ -26,15 +26,21 @@
#define IPL_DEVICE (*(unsigned long *) (0x10404))
#define INITRD_START (*(unsigned long *) (0x1040C))
#define INITRD_SIZE (*(unsigned long *) (0x10414))
#define OLDMEM_BASE (*(unsigned long *) (0x1041C))
#define OLDMEM_SIZE (*(unsigned long *) (0x10424))
#else /* __s390x__ */
#define IPL_DEVICE (*(unsigned long *) (0x10400))
#define INITRD_START (*(unsigned long *) (0x10408))
#define INITRD_SIZE (*(unsigned long *) (0x10410))
#define OLDMEM_BASE (*(unsigned long *) (0x10418))
#define OLDMEM_SIZE (*(unsigned long *) (0x10420))
#endif /* __s390x__ */
#define COMMAND_LINE ((char *) (0x10480))
#define CHUNK_READ_WRITE 0
#define CHUNK_READ_ONLY 1
#define CHUNK_OLDMEM 4
#define CHUNK_CRASHK 5
struct mem_chunk {
unsigned long addr;
......@@ -48,6 +54,8 @@ extern int memory_end_set;
extern unsigned long memory_end;
void detect_memory_layout(struct mem_chunk chunk[]);
void create_mem_hole(struct mem_chunk memory_chunk[], unsigned long addr,
unsigned long size, int type);
#define PRIMARY_SPACE_MODE 0
#define ACCESS_REGISTER_MODE 1
......@@ -106,6 +114,7 @@ extern unsigned int user_mode;
#endif /* __s390x__ */
#define ZFCPDUMP_HSA_SIZE (32UL<<20)
#define ZFCPDUMP_HSA_SIZE_MAX (64UL<<20)
/*
* Console mode. Override with conmode=
......@@ -134,10 +143,14 @@ extern char kernel_nss_name[];
#define IPL_DEVICE 0x10404
#define INITRD_START 0x1040C
#define INITRD_SIZE 0x10414
#define OLDMEM_BASE 0x1041C
#define OLDMEM_SIZE 0x10424
#else /* __s390x__ */
#define IPL_DEVICE 0x10400
#define INITRD_START 0x10408
#define INITRD_SIZE 0x10410
#define OLDMEM_BASE 0x10418
#define OLDMEM_SIZE 0x10420
#endif /* __s390x__ */
#define COMMAND_LINE 0x10480
......
......@@ -48,6 +48,7 @@ obj-$(CONFIG_FUNCTION_TRACER) += $(if $(CONFIG_64BIT),mcount64.o,mcount.o)
obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
# Kexec part
S390_KEXEC_OBJS := machine_kexec.o crash.o
......
......@@ -86,6 +86,8 @@ s390_base_pgm_handler_fn:
ENTRY(diag308_reset)
larl %r4,.Lctlregs # Save control registers
stctg %c0,%c15,0(%r4)
larl %r4,.Lfpctl # Floating point control register
stfpc 0(%r4)
larl %r4,.Lrestart_psw # Setup restart PSW at absolute 0
lghi %r3,0
lg %r4,0(%r4) # Save PSW
......@@ -99,6 +101,8 @@ ENTRY(diag308_reset)
sam64 # Switch to 64 bit addressing mode
larl %r4,.Lctlregs # Restore control registers
lctlg %c0,%c15,0(%r4)
larl %r4,.Lfpctl # Restore floating point ctl register
lfpc 0(%r4)
br %r14
.align 16
.Lrestart_psw:
......@@ -110,6 +114,8 @@ ENTRY(diag308_reset)
.rept 16
.quad 0
.endr
.Lfpctl:
.long 0
.previous
#else /* CONFIG_64BIT */
......
/*
* S390 kdump implementation
*
* Copyright IBM Corp. 2011
* Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
*/
#include <linux/crash_dump.h>
#include <asm/lowcore.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/crash_dump.h>
#include <linux/bootmem.h>
#include <linux/elf.h>
#include <asm/ipl.h>
#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
#define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))
/*
* Copy one page from "oldmem"
*
* For the kdump reserved memory this functions performs a swap operation:
* - [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] is mapped to [0 - OLDMEM_SIZE].
* - [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
*/
ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
size_t csize, unsigned long offset, int userbuf)
{
unsigned long src;
int rc;
if (!csize)
return 0;
src = (pfn << PAGE_SHIFT) + offset;
if (src < OLDMEM_SIZE)
src += OLDMEM_BASE;
else if (src > OLDMEM_BASE &&
src < OLDMEM_BASE + OLDMEM_SIZE)
src -= OLDMEM_BASE;
if (userbuf)
rc = copy_to_user_real((void __user *) buf, (void *) src,
csize);
else
rc = memcpy_real(buf, (void *) src, csize);
return rc < 0 ? rc : csize;
}
/*
* Copy memory from old kernel
*/
static int copy_from_oldmem(void *dest, void *src, size_t count)
{
unsigned long copied = 0;
int rc;
if ((unsigned long) src < OLDMEM_SIZE) {
copied = min(count, OLDMEM_SIZE - (unsigned long) src);
rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
if (rc)
return rc;
}
return memcpy_real(dest + copied, src + copied, count - copied);
}
/*
* Alloc memory and panic in case of ENOMEM
*/
static void *kzalloc_panic(int len)
{
void *rc;
rc = kzalloc(len, GFP_KERNEL);
if (!rc)
panic("s390 kdump kzalloc (%d) failed", len);
return rc;
}
/*
* Get memory layout and create hole for oldmem
*/
static struct mem_chunk *get_memory_layout(void)
{
struct mem_chunk *chunk_array;
chunk_array = kzalloc_panic(MEMORY_CHUNKS * sizeof(struct mem_chunk));
detect_memory_layout(chunk_array);
create_mem_hole(chunk_array, OLDMEM_BASE, OLDMEM_SIZE, CHUNK_CRASHK);
return chunk_array;
}
/*
* Initialize ELF note
*/
static void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len,
const char *name)
{
Elf64_Nhdr *note;
u64 len;
note = (Elf64_Nhdr *)buf;
note->n_namesz = strlen(name) + 1;
note->n_descsz = d_len;
note->n_type = type;
len = sizeof(Elf64_Nhdr);
memcpy(buf + len, name, note->n_namesz);
len = roundup(len + note->n_namesz, 4);
memcpy(buf + len, desc, note->n_descsz);
len = roundup(len + note->n_descsz, 4);
return PTR_ADD(buf, len);
}
/*
* Initialize prstatus note
*/
static void *nt_prstatus(void *ptr, struct save_area *sa)
{
struct elf_prstatus nt_prstatus;
static int cpu_nr = 1;
memset(&nt_prstatus, 0, sizeof(nt_prstatus));
memcpy(&nt_prstatus.pr_reg.gprs, sa->gp_regs, sizeof(sa->gp_regs));
memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
memcpy(&nt_prstatus.pr_reg.acrs, sa->acc_regs, sizeof(sa->acc_regs));
nt_prstatus.pr_pid = cpu_nr;
cpu_nr++;
return nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus),
"CORE");
}
/*
* Initialize fpregset (floating point) note
*/
static void *nt_fpregset(void *ptr, struct save_area *sa)
{
elf_fpregset_t nt_fpregset;
memset(&nt_fpregset, 0, sizeof(nt_fpregset));
memcpy(&nt_fpregset.fpc, &sa->fp_ctrl_reg, sizeof(sa->fp_ctrl_reg));
memcpy(&nt_fpregset.fprs, &sa->fp_regs, sizeof(sa->fp_regs));
return nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset),
"CORE");
}
/*
* Initialize timer note
*/
static void *nt_s390_timer(void *ptr, struct save_area *sa)
{
return nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer),
KEXEC_CORE_NOTE_NAME);
}
/*
* Initialize TOD clock comparator note
*/
static void *nt_s390_tod_cmp(void *ptr, struct save_area *sa)
{
return nt_init(ptr, NT_S390_TODCMP, &sa->clk_cmp,
sizeof(sa->clk_cmp), KEXEC_CORE_NOTE_NAME);
}
/*
* Initialize TOD programmable register note
*/
static void *nt_s390_tod_preg(void *ptr, struct save_area *sa)
{
return nt_init(ptr, NT_S390_TODPREG, &sa->tod_reg,
sizeof(sa->tod_reg), KEXEC_CORE_NOTE_NAME);
}
/*
* Initialize control register note
*/
static void *nt_s390_ctrs(void *ptr, struct save_area *sa)
{
return nt_init(ptr, NT_S390_CTRS, &sa->ctrl_regs,
sizeof(sa->ctrl_regs), KEXEC_CORE_NOTE_NAME);
}
/*
* Initialize prefix register note
*/
static void *nt_s390_prefix(void *ptr, struct save_area *sa)
{
return nt_init(ptr, NT_S390_PREFIX, &sa->pref_reg,
sizeof(sa->pref_reg), KEXEC_CORE_NOTE_NAME);
}
/*
* Fill ELF notes for one CPU with save area registers
*/
void *fill_cpu_elf_notes(void *ptr, struct save_area *sa)
{
ptr = nt_prstatus(ptr, sa);
ptr = nt_fpregset(ptr, sa);
ptr = nt_s390_timer(ptr, sa);
ptr = nt_s390_tod_cmp(ptr, sa);
ptr = nt_s390_tod_preg(ptr, sa);
ptr = nt_s390_ctrs(ptr, sa);
ptr = nt_s390_prefix(ptr, sa);
return ptr;
}
/*
* Initialize prpsinfo note (new kernel)
*/
static void *nt_prpsinfo(void *ptr)
{
struct elf_prpsinfo prpsinfo;
memset(&prpsinfo, 0, sizeof(prpsinfo));
prpsinfo.pr_sname = 'R';
strcpy(prpsinfo.pr_fname, "vmlinux");
return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo),
KEXEC_CORE_NOTE_NAME);
}
/*
* Initialize vmcoreinfo note (new kernel)
*/
static void *nt_vmcoreinfo(void *ptr)
{
char nt_name[11], *vmcoreinfo;
Elf64_Nhdr note;
void *addr;
if (copy_from_oldmem(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
return ptr;
memset(nt_name, 0, sizeof(nt_name));
if (copy_from_oldmem(&note, addr, sizeof(note)))
return ptr;
if (copy_from_oldmem(nt_name, addr + sizeof(note), sizeof(nt_name) - 1))
return ptr;
if (strcmp(nt_name, "VMCOREINFO") != 0)
return ptr;
vmcoreinfo = kzalloc_panic(note.n_descsz + 1);
if (copy_from_oldmem(vmcoreinfo, addr + 24, note.n_descsz))
return ptr;
vmcoreinfo[note.n_descsz + 1] = 0;
return nt_init(ptr, 0, vmcoreinfo, note.n_descsz, "VMCOREINFO");
}
/*
* Initialize ELF header (new kernel)
*/
static void *ehdr_init(Elf64_Ehdr *ehdr, int mem_chunk_cnt)
{
memset(ehdr, 0, sizeof(*ehdr));
memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
ehdr->e_ident[EI_CLASS] = ELFCLASS64;
ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
ehdr->e_ident[EI_VERSION] = EV_CURRENT;
memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
ehdr->e_type = ET_CORE;
ehdr->e_machine = EM_S390;
ehdr->e_version = EV_CURRENT;
ehdr->e_phoff = sizeof(Elf64_Ehdr);
ehdr->e_ehsize = sizeof(Elf64_Ehdr);
ehdr->e_phentsize = sizeof(Elf64_Phdr);
ehdr->e_phnum = mem_chunk_cnt + 1;
return ehdr + 1;
}
/*
* Return CPU count for ELF header (new kernel)
*/
static int get_cpu_cnt(void)
{
int i, cpus = 0;
for (i = 0; zfcpdump_save_areas[i]; i++) {
if (zfcpdump_save_areas[i]->pref_reg == 0)
continue;
cpus++;
}
return cpus;
}
/*
* Return memory chunk count for ELF header (new kernel)
*/
static int get_mem_chunk_cnt(void)
{
struct mem_chunk *chunk_array, *mem_chunk;
int i, cnt = 0;
chunk_array = get_memory_layout();
for (i = 0; i < MEMORY_CHUNKS; i++) {
mem_chunk = &chunk_array[i];
if (chunk_array[i].type != CHUNK_READ_WRITE &&
chunk_array[i].type != CHUNK_READ_ONLY)
continue;
if (mem_chunk->size == 0)
continue;
cnt++;
}
kfree(chunk_array);
return cnt;
}
/*
* Relocate pointer in order to allow vmcore code access the data
*/
static inline unsigned long relocate(unsigned long addr)
{
return OLDMEM_BASE + addr;
}
/*
* Initialize ELF loads (new kernel)
*/
static int loads_init(Elf64_Phdr *phdr, u64 loads_offset)
{
struct mem_chunk *chunk_array, *mem_chunk;
int i;
chunk_array = get_memory_layout();
for (i = 0; i < MEMORY_CHUNKS; i++) {
mem_chunk = &chunk_array[i];
if (mem_chunk->size == 0)
break;
if (chunk_array[i].type != CHUNK_READ_WRITE &&
chunk_array[i].type != CHUNK_READ_ONLY)
continue;
else
phdr->p_filesz = mem_chunk->size;
phdr->p_type = PT_LOAD;
phdr->p_offset = mem_chunk->addr;
phdr->p_vaddr = mem_chunk->addr;
phdr->p_paddr = mem_chunk->addr;
phdr->p_memsz = mem_chunk->size;
phdr->p_flags = PF_R | PF_W | PF_X;
phdr->p_align = PAGE_SIZE;
phdr++;
}
kfree(chunk_array);
return i;
}
/*
* Initialize notes (new kernel)
*/
static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
{
struct save_area *sa;
void *ptr_start = ptr;
int i;
ptr = nt_prpsinfo(ptr);
for (i = 0; zfcpdump_save_areas[i]; i++) {
sa = zfcpdump_save_areas[i];
if (sa->pref_reg == 0)
continue;
ptr = fill_cpu_elf_notes(ptr, sa);
}
ptr = nt_vmcoreinfo(ptr);
memset(phdr, 0, sizeof(*phdr));
phdr->p_type = PT_NOTE;
phdr->p_offset = relocate(notes_offset);
phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
phdr->p_memsz = phdr->p_filesz;
return ptr;
}
/*
* Create ELF core header (new kernel)
*/
static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz)
{
Elf64_Phdr *phdr_notes, *phdr_loads;
int mem_chunk_cnt;
void *ptr, *hdr;
u32 alloc_size;
u64 hdr_off;
mem_chunk_cnt = get_mem_chunk_cnt();
alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
mem_chunk_cnt * sizeof(Elf64_Phdr);
hdr = kzalloc_panic(alloc_size);
/* Init elf header */
ptr = ehdr_init(hdr, mem_chunk_cnt);
/* Init program headers */
phdr_notes = ptr;
ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr));
phdr_loads = ptr;
ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt);
/* Init notes */
hdr_off = PTR_DIFF(ptr, hdr);
ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
/* Init loads */
hdr_off = PTR_DIFF(ptr, hdr);
loads_init(phdr_loads, ((unsigned long) hdr) + hdr_off);
*elfcorebuf_sz = hdr_off;
*elfcorebuf = (void *) relocate((unsigned long) hdr);
BUG_ON(*elfcorebuf_sz > alloc_size);
}
/*
* Create kdump ELF core header in new kernel, if it has not been passed via
* the "elfcorehdr" kernel parameter
*/
static int setup_kdump_elfcorehdr(void)
{
size_t elfcorebuf_sz;
char *elfcorebuf;
if (!OLDMEM_BASE || is_kdump_kernel())
return -EINVAL;
s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz);
elfcorehdr_addr = (unsigned long long) elfcorebuf;
elfcorehdr_size = elfcorebuf_sz;
return 0;
}
subsys_initcall(setup_kdump_elfcorehdr);
......@@ -449,10 +449,28 @@ ENTRY(start)
#
.org 0x10000
ENTRY(startup)
j .Lep_startup_normal
.org 0x10008
#
# This is a list of s390 kernel entry points. At address 0x1000f the number of
# valid entry points is stored.
#
# IMPORTANT: Do not change this table, it is s390 kernel ABI!
#
.ascii "S390EP"
.byte 0x00,0x01
#
# kdump startup-code at 0x10010, running in 64 bit absolute addressing mode
#
.org 0x10010
ENTRY(startup_kdump)
j .Lep_startup_kdump
.Lep_startup_normal:
basr %r13,0 # get base
.LPG0:
xc 0x200(256),0x200 # partially clear lowcore
xc 0x300(256),0x300
xc 0xe00(256),0xe00
stck __LC_LAST_UPDATE_CLOCK
spt 5f-.LPG0(%r13)
mvc __LC_LAST_UPDATE_TIMER(8),5f-.LPG0(%r13)
......@@ -534,6 +552,8 @@ ENTRY(startup)
.align 8
5: .long 0x7fffffff,0xffffffff
#include "head_kdump.S"
#
# params at 10400 (setup.h)
#
......@@ -541,6 +561,8 @@ ENTRY(startup)
.long 0,0 # IPL_DEVICE
.long 0,0 # INITRD_START
.long 0,0 # INITRD_SIZE
.long 0,0 # OLDMEM_BASE
.long 0,0 # OLDMEM_SIZE
.org COMMAND_LINE
.byte "root=/dev/ram0 ro"
......
/*
* S390 kdump lowlevel functions (new kernel)
*
* Copyright IBM Corp. 2011
* Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
*/
#define DATAMOVER_ADDR 0x4000
#define COPY_PAGE_ADDR 0x6000
#ifdef CONFIG_CRASH_DUMP
#