From 23df79da8eb97757e39af7625665c1c5cecc610b Mon Sep 17 00:00:00 2001 From: Jan Willeke Date: Wed, 11 Sep 2013 14:24:52 -0700 Subject: 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 Signed-off-by: Michael Holzheu Cc: HATAYAMA Daisuke Cc: Vivek Goyal Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/s390/kernel/crash_dump.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'arch/s390') diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index 0c9a897a1fb5..3e776158b330 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -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 */ -- cgit v1.2.3