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| author | Jan Willeke <willeke@de.ibm.com> | 2013-09-11 23:24:52 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-09-12 00:59:12 +0200 |
| commit | 23df79da8eb97757e39af7625665c1c5cecc610b (patch) | |
| tree | 698c1324379af2f235cd81a5e4072369fac47976 /arch/s390 | |
| parent | vmcore: introduce remap_oldmem_pfn_range() (diff) | |
| download | linux-23df79da8eb97757e39af7625665c1c5cecc610b.tar.xz linux-23df79da8eb97757e39af7625665c1c5cecc610b.zip | |
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>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/kernel/crash_dump.c | 26 |
1 files changed, 26 insertions, 0 deletions
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 @@ -99,6 +99,32 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, } /* + * 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 */ int copy_from_oldmem(void *dest, void *src, size_t count) |