s390/vmcore: implement remap_oldmem_pfn_range for s390

Introduce the s390 specific way to map pages from oldmem.  The memory area
below OLDMEM_SIZE is mapped with offset OLDMEM_BASE.  The other old memory
is mapped directly.

Signed-off-by: Jan Willeke <willeke@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.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:
Jan Willeke 2013-09-11 14:24:52 -07:00 committed by Linus Torvalds
parent 9cb218131d
commit 23df79da8e
1 changed files with 26 additions and 0 deletions

View File

@ -98,6 +98,32 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
return (rc == 0) ? csize : rc;
}
/*
* Remap "oldmem"
*
* 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)
{
unsigned long size_old;
int rc;
if (pfn < OLDMEM_SIZE >> PAGE_SHIFT) {
size_old = min(size, OLDMEM_SIZE - (pfn << PAGE_SHIFT));
rc = remap_pfn_range(vma, from,
pfn + (OLDMEM_BASE >> PAGE_SHIFT),
size_old, prot);
if (rc || size == size_old)
return rc;
size -= size_old;
from += size_old;
pfn += size_old >> PAGE_SHIFT;
}
return remap_pfn_range(vma, from, pfn, size, prot);
}
/*
* Copy memory from old kernel
*/