[patch 011/114] mm: fix memmap init for handling memory hole

Greg KH
2009-03-14T01:24:08Z

[-- Attachment #1: mm-fix-memmap-init-for-handling-memory-hole.patch --]
[-- Type: text/plain, Size: 2502 bytes --]

2.6.28-stable review patch. If anyone has any objections, please let us know.

------------------

From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

commit cc2559bccc72767cb446f79b071d96c30c26439b upstream.

Now, early_pfn_in_nid(PFN, NID) may returns false if PFN is a hole.
and memmap initialization was not done. This was a trouble for
sparc boot.

To fix this, the PFN should be initialized and marked as PG_reserved.
This patch changes early_pfn_in_nid() return true if PFN is a hole.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
arch/ia64/mm/numa.c | 2 +-
include/linux/mmzone.h | 2 +-
mm/page_alloc.c | 23 ++++++++++++++++++++---
3 files changed, 22 insertions(+), 5 deletions(-)

--- a/arch/ia64/mm/numa.c
+++ b/arch/ia64/mm/numa.c
@@ -70,7 +70,7 @@ int __meminit __early_pfn_to_nid(unsigne
return node_memblk[i].nid;
}

- return 0;
+ return -1;
}

#ifdef CONFIG_MEMORY_HOTPLUG
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1067,7 +1067,7 @@ void sparse_init(void);
#endif /* CONFIG_SPARSEMEM */

#ifdef CONFIG_NODES_SPAN_OTHER_NODES
-#define early_pfn_in_nid(pfn, nid) (early_pfn_to_nid(pfn) == (nid))
+bool early_pfn_in_nid(unsigned long pfn, int nid);
#else
#define early_pfn_in_nid(pfn, nid) (1)
#endif
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2985,16 +2985,33 @@ int __meminit __early_pfn_to_nid(unsigne
if (start_pfn <= pfn && pfn < end_pfn)
return early_node_map[i].nid;
}
-
- return 0;
+ /* This is a memory hole */
+ return -1;
}
#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */

int __meminit early_pfn_to_nid(unsigned long pfn)
{
- return __early_pfn_to_nid(pfn);
+ int nid;
+
+ nid = __early_pfn_to_nid(pfn);
+ if (nid >= 0)
+ return nid;
+ /* just returns 0 */
+ return 0;
}

+#ifdef CONFIG_NODES_SPAN_OTHER_NODES
+bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
+{
+ int nid;
+
+ nid = __early_pfn_to_nid(pfn);
+ if (nid >= 0 && nid != node)
+ return false;
+ return true;
+}
+#endif

/* Basic iterator support to walk early_node_map[] */
#define for_each_active_range_index_in_nid(i, nid) \