[S390] kernel: Add OS info memory interface
In order to allow kdump based stand-alone dump, some information
has to be passed from the old kernel to the new dump kernel. This
is done via a the struct "os_info" that contains the following fields:
* crashkernel base and size
* reipl block
* vmcoreinfo
* init function
A pointer to os_info is stored at a well known storage location
and the whole structure as well as all fields are secured with
checksums.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index 4e69563..a47c6e2 100644
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -154,7 +154,9 @@
__u32 ipib; /* 0x0e00 */
__u32 ipib_checksum; /* 0x0e04 */
__u32 vmcore_info; /* 0x0e08 */
- __u8 pad_0x0e0c[0x0f00-0x0e0c]; /* 0x0e0c */
+ __u8 pad_0x0e0c[0x0e18-0x0e0c]; /* 0x0e0c */
+ __u32 os_info; /* 0x0e18 */
+ __u8 pad_0x0e1c[0x0f00-0x0e1c]; /* 0x0e1c */
/* Extended facility list */
__u64 stfle_fac_list[32]; /* 0x0f00 */
@@ -301,7 +303,9 @@
__u64 ipib; /* 0x0e00 */
__u32 ipib_checksum; /* 0x0e08 */
__u64 vmcore_info; /* 0x0e0c */
- __u8 pad_0x0e14[0x0f00-0x0e14]; /* 0x0e14 */
+ __u8 pad_0x0e14[0x0e18-0x0e14]; /* 0x0e14 */
+ __u64 os_info; /* 0x0e18 */
+ __u8 pad_0x0e20[0x0f00-0x0e20]; /* 0x0e20 */
/* Extended facility list */
__u64 stfle_fac_list[32]; /* 0x0f00 */
diff --git a/arch/s390/include/asm/os_info.h b/arch/s390/include/asm/os_info.h
new file mode 100644
index 0000000..d07518af
--- /dev/null
+++ b/arch/s390/include/asm/os_info.h
@@ -0,0 +1,50 @@
+/*
+ * OS info memory interface
+ *
+ * Copyright IBM Corp. 2012
+ * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
+ */
+#ifndef _ASM_S390_OS_INFO_H
+#define _ASM_S390_OS_INFO_H
+
+#define OS_INFO_VERSION_MAJOR 1
+#define OS_INFO_VERSION_MINOR 1
+#define OS_INFO_MAGIC 0x4f53494e464f535aULL /* OSINFOSZ */
+
+#define OS_INFO_VMCOREINFO 0
+#define OS_INFO_REIPL_BLOCK 1
+#define OS_INFO_INIT_FN 2
+
+struct os_info_entry {
+ u64 addr;
+ u64 size;
+ u32 csum;
+} __packed;
+
+struct os_info {
+ u64 magic;
+ u32 csum;
+ u16 version_major;
+ u16 version_minor;
+ u64 crashkernel_addr;
+ u64 crashkernel_size;
+ struct os_info_entry entry[3];
+ u8 reserved[4004];
+} __packed;
+
+void os_info_init(void);
+void os_info_entry_add(int nr, void *ptr, u64 len);
+void os_info_crashkernel_add(unsigned long base, unsigned long size);
+u32 os_info_csum(struct os_info *os_info);
+
+#ifdef CONFIG_CRASH_DUMP
+void *os_info_old_entry(int nr, unsigned long *size);
+int copy_from_oldmem(void *dest, void *src, size_t count);
+#else
+static inline void *os_info_old_entry(int nr, unsigned long *size)
+{
+ return NULL;
+}
+#endif
+
+#endif /* _ASM_S390_OS_INFO_H */
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index b215950..16b0b43 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -23,7 +23,7 @@
obj-y := bitmap.o traps.o time.o process.o base.o early.o setup.o vtime.o \
processor.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o nmi.o \
debug.o irq.o ipl.o dis.o diag.o mem_detect.o sclp.o vdso.o \
- sysinfo.o jump_label.o lgr.o
+ sysinfo.o jump_label.o lgr.o os_info.o
obj-y += $(if $(CONFIG_64BIT),entry64.o,entry.o)
obj-y += $(if $(CONFIG_64BIT),reipl64.o,reipl.o)
diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c
index c383ce4..cc1172b 100644
--- a/arch/s390/kernel/crash_dump.c
+++ b/arch/s390/kernel/crash_dump.c
@@ -14,6 +14,7 @@
#include <linux/bootmem.h>
#include <linux/elf.h>
#include <asm/ipl.h>
+#include <asm/os_info.h>
#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
@@ -51,7 +52,7 @@
/*
* Copy memory from old kernel
*/
-static int copy_from_oldmem(void *dest, void *src, size_t count)
+int copy_from_oldmem(void *dest, void *src, size_t count)
{
unsigned long copied = 0;
int rc;
@@ -224,28 +225,44 @@
}
/*
- * Initialize vmcoreinfo note (new kernel)
+ * Get vmcoreinfo using lowcore->vmcore_info (new kernel)
*/
-static void *nt_vmcoreinfo(void *ptr)
+static void *get_vmcoreinfo_old(unsigned long *size)
{
char nt_name[11], *vmcoreinfo;
Elf64_Nhdr note;
void *addr;
if (copy_from_oldmem(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
- return ptr;
+ return NULL;
memset(nt_name, 0, sizeof(nt_name));
if (copy_from_oldmem(¬e, addr, sizeof(note)))
- return ptr;
+ return NULL;
if (copy_from_oldmem(nt_name, addr + sizeof(note), sizeof(nt_name) - 1))
- return ptr;
+ return NULL;
if (strcmp(nt_name, "VMCOREINFO") != 0)
- return ptr;
- vmcoreinfo = kzalloc_panic(note.n_descsz + 1);
+ return NULL;
+ vmcoreinfo = kzalloc_panic(note.n_descsz);
if (copy_from_oldmem(vmcoreinfo, addr + 24, note.n_descsz))
+ return NULL;
+ *size = note.n_descsz;
+ return vmcoreinfo;
+}
+
+/*
+ * Initialize vmcoreinfo note (new kernel)
+ */
+static void *nt_vmcoreinfo(void *ptr)
+{
+ unsigned long size;
+ void *vmcoreinfo;
+
+ vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
+ if (!vmcoreinfo)
+ vmcoreinfo = get_vmcoreinfo_old(&size);
+ if (!vmcoreinfo)
return ptr;
- vmcoreinfo[note.n_descsz + 1] = 0;
- return nt_init(ptr, 0, vmcoreinfo, note.n_descsz, "VMCOREINFO");
+ return nt_init(ptr, 0, vmcoreinfo, size, "VMCOREINFO");
}
/*
diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index 153e21c..8342e65 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -28,6 +28,7 @@
#include <asm/sclp.h>
#include <asm/checksum.h>
#include <asm/debug.h>
+#include <asm/os_info.h>
#include "entry.h"
#define IPL_PARM_BLOCK_VERSION 0
@@ -951,6 +952,13 @@
.attrs = reipl_nss_attrs,
};
+static void set_reipl_block_actual(struct ipl_parameter_block *reipl_block)
+{
+ reipl_block_actual = reipl_block;
+ os_info_entry_add(OS_INFO_REIPL_BLOCK, reipl_block_actual,
+ reipl_block->hdr.len);
+}
+
/* reipl type */
static int reipl_set_type(enum ipl_type type)
@@ -966,7 +974,7 @@
reipl_method = REIPL_METHOD_CCW_VM;
else
reipl_method = REIPL_METHOD_CCW_CIO;
- reipl_block_actual = reipl_block_ccw;
+ set_reipl_block_actual(reipl_block_ccw);
break;
case IPL_TYPE_FCP:
if (diag308_set_works)
@@ -975,7 +983,7 @@
reipl_method = REIPL_METHOD_FCP_RO_VM;
else
reipl_method = REIPL_METHOD_FCP_RO_DIAG;
- reipl_block_actual = reipl_block_fcp;
+ set_reipl_block_actual(reipl_block_fcp);
break;
case IPL_TYPE_FCP_DUMP:
reipl_method = REIPL_METHOD_FCP_DUMP;
@@ -985,7 +993,7 @@
reipl_method = REIPL_METHOD_NSS_DIAG;
else
reipl_method = REIPL_METHOD_NSS;
- reipl_block_actual = reipl_block_nss;
+ set_reipl_block_actual(reipl_block_nss);
break;
case IPL_TYPE_UNKNOWN:
reipl_method = REIPL_METHOD_DEFAULT;
@@ -1257,6 +1265,29 @@
return 0;
}
+static int __init reipl_type_init(void)
+{
+ enum ipl_type reipl_type = ipl_info.type;
+ struct ipl_parameter_block *reipl_block;
+ unsigned long size;
+
+ reipl_block = os_info_old_entry(OS_INFO_REIPL_BLOCK, &size);
+ if (!reipl_block)
+ goto out;
+ /*
+ * If we have an OS info reipl block, this will be used
+ */
+ if (reipl_block->hdr.pbt == DIAG308_IPL_TYPE_FCP) {
+ memcpy(reipl_block_fcp, reipl_block, size);
+ reipl_type = IPL_TYPE_FCP;
+ } else if (reipl_block->hdr.pbt == DIAG308_IPL_TYPE_CCW) {
+ memcpy(reipl_block_ccw, reipl_block, size);
+ reipl_type = IPL_TYPE_CCW;
+ }
+out:
+ return reipl_set_type(reipl_type);
+}
+
static int __init reipl_init(void)
{
int rc;
@@ -1278,10 +1309,7 @@
rc = reipl_nss_init();
if (rc)
return rc;
- rc = reipl_set_type(ipl_info.type);
- if (rc)
- return rc;
- return 0;
+ return reipl_type_init();
}
static struct shutdown_action __refdata reipl_action = {
diff --git a/arch/s390/kernel/os_info.c b/arch/s390/kernel/os_info.c
new file mode 100644
index 0000000..bbe5226
--- /dev/null
+++ b/arch/s390/kernel/os_info.c
@@ -0,0 +1,169 @@
+/*
+ * OS info memory interface
+ *
+ * Copyright IBM Corp. 2012
+ * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
+ */
+
+#define KMSG_COMPONENT "os_info"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/crash_dump.h>
+#include <linux/kernel.h>
+#include <asm/checksum.h>
+#include <asm/lowcore.h>
+#include <asm/system.h>
+#include <asm/os_info.h>
+
+/*
+ * OS info structure has to be page aligned
+ */
+static struct os_info os_info __page_aligned_data;
+
+/*
+ * Compute checksum over OS info structure
+ */
+u32 os_info_csum(struct os_info *os_info)
+{
+ int size = sizeof(*os_info) - offsetof(struct os_info, version_major);
+ return csum_partial(&os_info->version_major, size, 0);
+}
+
+/*
+ * Add crashkernel info to OS info and update checksum
+ */
+void os_info_crashkernel_add(unsigned long base, unsigned long size)
+{
+ os_info.crashkernel_addr = (u64)(unsigned long)base;
+ os_info.crashkernel_size = (u64)(unsigned long)size;
+ os_info.csum = os_info_csum(&os_info);
+}
+
+/*
+ * Add OS info entry and update checksum
+ */
+void os_info_entry_add(int nr, void *ptr, u64 size)
+{
+ os_info.entry[nr].addr = (u64)(unsigned long)ptr;
+ os_info.entry[nr].size = size;
+ os_info.entry[nr].csum = csum_partial(ptr, size, 0);
+ os_info.csum = os_info_csum(&os_info);
+}
+
+/*
+ * Initialize OS info struture and set lowcore pointer
+ */
+void __init os_info_init(void)
+{
+ void *ptr = &os_info;
+
+ os_info.version_major = OS_INFO_VERSION_MAJOR;
+ os_info.version_minor = OS_INFO_VERSION_MINOR;
+ os_info.magic = OS_INFO_MAGIC;
+ os_info.csum = os_info_csum(&os_info);
+ copy_to_absolute_zero(&S390_lowcore.os_info, &ptr, sizeof(ptr));
+}
+
+#ifdef CONFIG_CRASH_DUMP
+
+static struct os_info *os_info_old;
+
+/*
+ * Allocate and copy OS info entry from oldmem
+ */
+static void os_info_old_alloc(int nr, int align)
+{
+ unsigned long addr, size = 0;
+ char *buf, *buf_align, *msg;
+ u32 csum;
+
+ addr = os_info_old->entry[nr].addr;
+ if (!addr) {
+ msg = "not available";
+ goto fail;
+ }
+ size = os_info_old->entry[nr].size;
+ buf = kmalloc(size + align - 1, GFP_KERNEL);
+ if (!buf) {
+ msg = "alloc failed";
+ goto fail;
+ }
+ buf_align = PTR_ALIGN(buf, align);
+ if (copy_from_oldmem(buf_align, (void *) addr, size)) {
+ msg = "copy failed";
+ goto fail_free;
+ }
+ csum = csum_partial(buf_align, size, 0);
+ if (csum != os_info_old->entry[nr].csum) {
+ msg = "checksum failed";
+ goto fail_free;
+ }
+ os_info_old->entry[nr].addr = (u64)(unsigned long)buf_align;
+ msg = "copied";
+ goto out;
+fail_free:
+ kfree(buf);
+fail:
+ os_info_old->entry[nr].addr = 0;
+out:
+ pr_info("entry %i: %s (addr=0x%lx size=%lu)\n",
+ nr, msg, addr, size);
+}
+
+/*
+ * Initialize os info and os info entries from oldmem
+ */
+static void os_info_old_init(void)
+{
+ static int os_info_init;
+ unsigned long addr;
+
+ if (os_info_init)
+ return;
+ if (!OLDMEM_BASE)
+ goto fail;
+ if (copy_from_oldmem(&addr, &S390_lowcore.os_info, sizeof(addr)))
+ goto fail;
+ if (addr == 0 || addr % PAGE_SIZE)
+ goto fail;
+ os_info_old = kzalloc(sizeof(*os_info_old), GFP_KERNEL);
+ if (!os_info_old)
+ goto fail;
+ if (copy_from_oldmem(os_info_old, (void *) addr, sizeof(*os_info_old)))
+ goto fail_free;
+ if (os_info_old->magic != OS_INFO_MAGIC)
+ goto fail_free;
+ if (os_info_old->csum != os_info_csum(os_info_old))
+ goto fail_free;
+ if (os_info_old->version_major > OS_INFO_VERSION_MAJOR)
+ goto fail_free;
+ os_info_old_alloc(OS_INFO_VMCOREINFO, 1);
+ os_info_old_alloc(OS_INFO_REIPL_BLOCK, 1);
+ os_info_old_alloc(OS_INFO_INIT_FN, PAGE_SIZE);
+ pr_info("crashkernel: addr=0x%lx size=%lu\n",
+ (unsigned long) os_info_old->crashkernel_addr,
+ (unsigned long) os_info_old->crashkernel_size);
+ os_info_init = 1;
+ return;
+fail_free:
+ kfree(os_info_old);
+fail:
+ os_info_init = 1;
+ os_info_old = NULL;
+}
+
+/*
+ * Return pointer to os infor entry and its size
+ */
+void *os_info_old_entry(int nr, unsigned long *size)
+{
+ os_info_old_init();
+
+ if (!os_info_old)
+ return NULL;
+ if (!os_info_old->entry[nr].addr)
+ return NULL;
+ *size = (unsigned long) os_info_old->entry[nr].size;
+ return (void *)(unsigned long)os_info_old->entry[nr].addr;
+}
+#endif
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 9a3edb5..38e7512 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -62,6 +62,7 @@
#include <asm/ebcdic.h>
#include <asm/kvm_virtio.h>
#include <asm/diag.h>
+#include <asm/os_info.h>
#include "entry.h"
long psw_kernel_bits = PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_ASC_PRIMARY |
@@ -778,6 +779,7 @@
pr_info("Reserving %lluMB of memory at %lluMB "
"for crashkernel (System RAM: %luMB)\n",
crash_size >> 20, crash_base >> 20, memory_end >> 20);
+ os_info_crashkernel_add(crash_base, crash_size);
#endif
}
@@ -1057,6 +1059,7 @@
parse_early_param();
+ os_info_init();
setup_ipl();
setup_memory_end();
setup_addressing_mode();
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index d15b6c9..3b9e5c9 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -41,6 +41,7 @@
#include <asm/sclp.h>
#include <asm/vdso.h>
#include <asm/debug.h>
+#include <asm/os_info.h>
#include "entry.h"
enum {
@@ -826,6 +827,17 @@
#endif /* CONFIG_HOTPLUG_CPU */
+static void smp_call_os_info_init_fn(void)
+{
+ int (*init_fn)(void);
+ unsigned long size;
+
+ init_fn = os_info_old_entry(OS_INFO_INIT_FN, &size);
+ if (!init_fn)
+ return;
+ init_fn();
+}
+
void __init smp_prepare_cpus(unsigned int max_cpus)
{
/* request the 0x1201 emergency signal external interrupt */
@@ -834,6 +846,7 @@
/* request the 0x1202 external call external interrupt */
if (register_external_interrupt(0x1202, do_ext_call_interrupt) != 0)
panic("Couldn't request external interrupt 0x1202");
+ smp_call_os_info_init_fn();
smp_detect_cpus();
}
