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authorJan Willeke <willeke@de.ibm.com>2013-09-12 01:24:52 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-09-12 02:59:12 +0400
commit23df79da8eb97757e39af7625665c1c5cecc610b (patch)
tree698c1324379af2f235cd81a5e4072369fac47976
parent9cb218131de1c59dca9063b2efe876f053f316af (diff)
downloadlinux-23df79da8eb97757e39af7625665c1c5cecc610b.tar.xz
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>
-rw-r--r--arch/s390/kernel/crash_dump.c26
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)