s390/vmcore: use vmcore for zfcpdump

Modify the s390 copy_oldmem_page() and remap_oldmem_pfn_range() function
for zfcpdump to read from the HSA memory if memory below HSA_SIZE bytes is
requested.  Otherwise real memory is used.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Jan Willeke <willeke@de.ibm.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michael Holzheu 2013-09-11 14:24:54 -07:00 committed by Linus Torvalds
parent 11e376a3f9
commit 6f79d33228
4 changed files with 110 additions and 22 deletions

View File

@ -526,6 +526,7 @@ config CRASH_DUMP
bool "kernel crash dumps"
depends on 64BIT && SMP
select KEXEC
select ZFCPDUMP
help
Generate crash dump after being started by kexec.
Crash dump kernels are loaded in the main kernel with kexec-tools
@ -536,7 +537,7 @@ config CRASH_DUMP
config ZFCPDUMP
def_bool n
prompt "zfcpdump support"
select SMP
depends on SMP
help
Select this option if you want to build an zfcpdump enabled kernel.
Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.

View File

@ -56,5 +56,6 @@ bool sclp_has_linemode(void);
bool sclp_has_vt220(void);
int sclp_pci_configure(u32 fid);
int sclp_pci_deconfigure(u32 fid);
int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode);
#endif /* _ASM_S390_SCLP_H */

View File

@ -16,6 +16,7 @@
#include <asm/os_info.h>
#include <asm/elf.h>
#include <asm/ipl.h>
#include <asm/sclp.h>
#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
@ -69,22 +70,41 @@ static ssize_t copy_page_real(void *buf, void *src, size_t csize)
static void *elfcorehdr_newmem;
/*
* Copy one page from "oldmem"
* Copy one page from zfcpdump "oldmem"
*
* For pages below ZFCPDUMP_HSA_SIZE memory from the HSA is copied. Otherwise
* real memory copy is used.
*/
static ssize_t copy_oldmem_page_zfcpdump(char *buf, size_t csize,
unsigned long src, int userbuf)
{
int rc;
if (src < ZFCPDUMP_HSA_SIZE) {
rc = memcpy_hsa(buf, src, csize, userbuf);
} else {
if (userbuf)
rc = copy_to_user_real((void __force __user *) buf,
(void *) src, csize);
else
rc = memcpy_real(buf, (void *) src, csize);
}
return rc ? rc : csize;
}
/*
* Copy one page from kdump "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)
static ssize_t copy_oldmem_page_kdump(char *buf, size_t csize,
unsigned long src, 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 &&
@ -95,17 +115,35 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
(void *) src, csize);
else
rc = copy_page_real(buf, (void *) src, csize);
return (rc == 0) ? csize : rc;
return (rc == 0) ? rc : csize;
}
/*
* Remap "oldmem"
* Copy one page from "oldmem"
*/
ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize,
unsigned long offset, int userbuf)
{
unsigned long src;
if (!csize)
return 0;
src = (pfn << PAGE_SHIFT) + offset;
if (OLDMEM_BASE)
return copy_oldmem_page_kdump(buf, csize, src, userbuf);
else
return copy_oldmem_page_zfcpdump(buf, csize, src, userbuf);
}
/*
* Remap "oldmem" for kdump
*
* For the kdump reserved memory this functions performs a swap operation:
* [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
*/
int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
unsigned long pfn, unsigned long size, pgprot_t prot)
static int remap_oldmem_pfn_range_kdump(struct vm_area_struct *vma,
unsigned long from, unsigned long pfn,
unsigned long size, pgprot_t prot)
{
unsigned long size_old;
int rc;
@ -124,6 +162,43 @@ int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
return remap_pfn_range(vma, from, pfn, size, prot);
}
/*
* Remap "oldmem" for zfcpdump
*
* We only map available memory above ZFCPDUMP_HSA_SIZE. Memory below
* ZFCPDUMP_HSA_SIZE is read on demand using the copy_oldmem_page() function.
*/
static int remap_oldmem_pfn_range_zfcpdump(struct vm_area_struct *vma,
unsigned long from,
unsigned long pfn,
unsigned long size, pgprot_t prot)
{
unsigned long size_hsa;
if (pfn < ZFCPDUMP_HSA_SIZE >> PAGE_SHIFT) {
size_hsa = min(size, ZFCPDUMP_HSA_SIZE - (pfn << PAGE_SHIFT));
if (size == size_hsa)
return 0;
size -= size_hsa;
from += size_hsa;
pfn += size_hsa >> PAGE_SHIFT;
}
return remap_pfn_range(vma, from, pfn, size, prot);
}
/*
* Remap "oldmem" for kdump or zfcpdump
*/
int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
unsigned long pfn, unsigned long size, pgprot_t prot)
{
if (OLDMEM_BASE)
return remap_oldmem_pfn_range_kdump(vma, from, pfn, size, prot);
else
return remap_oldmem_pfn_range_zfcpdump(vma, from, pfn, size,
prot);
}
/*
* Copy memory from old kernel
*/
@ -132,11 +207,21 @@ 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;
if (OLDMEM_BASE) {
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;
}
} else {
if ((unsigned long) src < ZFCPDUMP_HSA_SIZE) {
copied = min(count,
ZFCPDUMP_HSA_SIZE - (unsigned long) src);
rc = memcpy_hsa(dest, (unsigned long) src, copied, 0);
if (rc)
return rc;
}
}
return memcpy_real(dest + copied, src + copied, count - copied);
}
@ -466,7 +551,8 @@ int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size)
u32 alloc_size;
u64 hdr_off;
if (!OLDMEM_BASE)
/* If we are not in kdump or zfcpdump mode return */
if (!OLDMEM_BASE && ipl_info.type != IPL_TYPE_FCP_DUMP)
return 0;
/* If elfcorehdr= has been passed via cmdline, we use that one */
if (elfcorehdr_addr != ELFCORE_ADDR_MAX)

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@ -30,8 +30,8 @@
#define TRACE(x...) debug_sprintf_event(zcore_dbf, 1, x)
#define TO_USER 0
#define TO_KERNEL 1
#define TO_USER 1
#define TO_KERNEL 0
#define CHUNK_INFO_SIZE 34 /* 2 16-byte char, each followed by blank */
enum arch_id {
@ -73,7 +73,7 @@ static struct ipl_parameter_block *ipl_block;
* @count: Size of buffer, which should be copied
* @mode: Either TO_KERNEL or TO_USER
*/
static int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode)
int memcpy_hsa(void *dest, unsigned long src, size_t count, int mode)
{
int offs, blk_num;
static char buf[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));