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authorKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>2007-10-16 01:26:10 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-16 09:43:01 -0700
commit75884fb1c6388f3713ddcca662f3647b3129aaeb (patch)
tree7debdd89fd94d099de3d3763b47af00ef6359d9d /kernel
parent48f13bf3e742fca8aab87f6c39451d03bf5952d4 (diff)
downloadop-kernel-dev-75884fb1c6388f3713ddcca662f3647b3129aaeb.zip
op-kernel-dev-75884fb1c6388f3713ddcca662f3647b3129aaeb.tar.gz
memory unplug: memory hotplug cleanup
A clean up patch for "scanning memory resource [start, end)" operation. Now, find_next_system_ram() function is used in memory hotplug, but this interface is not easy to use and codes are complicated. This patch adds walk_memory_resouce(start,len,arg,func) function. The function 'func' is called per valid memory resouce range in [start,pfn). [pbadari@us.ibm.com: Error handling in walk_memory_resource()] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/resource.c26
1 files changed, 25 insertions, 1 deletions
diff --git a/kernel/resource.c b/kernel/resource.c
index 9bd14fd..a358142 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -234,7 +234,7 @@ EXPORT_SYMBOL(release_resource);
* the caller must specify res->start, res->end, res->flags.
* If found, returns 0, res is overwritten, if not found, returns -1.
*/
-int find_next_system_ram(struct resource *res)
+static int find_next_system_ram(struct resource *res)
{
resource_size_t start, end;
struct resource *p;
@@ -267,6 +267,30 @@ int find_next_system_ram(struct resource *res)
res->end = p->end;
return 0;
}
+int
+walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
+ int (*func)(unsigned long, unsigned long, void *))
+{
+ struct resource res;
+ unsigned long pfn, len;
+ u64 orig_end;
+ int ret = -1;
+ res.start = (u64) start_pfn << PAGE_SHIFT;
+ res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
+ res.flags = IORESOURCE_MEM;
+ orig_end = res.end;
+ while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) {
+ pfn = (unsigned long)(res.start >> PAGE_SHIFT);
+ len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT);
+ ret = (*func)(pfn, len, arg);
+ if (ret)
+ break;
+ res.start = res.end + 1;
+ res.end = orig_end;
+ }
+ return ret;
+}
+
#endif
/*
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