walk system ram range
Originally, walk_memory_resource() was introduced to traverse all memory
of "System RAM" for detecting memory hotplug/unplug range. For doing so,
flags of IORESOUCE_MEM|IORESOURCE_BUSY was used and this was enough for
memory hotplug.
But for using other purpose, /proc/kcore, this may includes some firmware
area marked as IORESOURCE_BUSY | IORESOUCE_MEM. This patch makes the
check strict to find out busy "System RAM".
Note: PPC64 keeps their own walk_memory_resouce(), which walk through
ppc64's lmb informaton. Because old kclist_add() is called per lmb, this
patch makes no difference in behavior, finally.
And this patch removes CONFIG_MEMORY_HOTPLUG check from this function.
Because pfn_valid() just show "there is memmap or not* and cannot be used
for "there is physical memory or not", this function is useful in generic
to scan physical memory range.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Américo Wang <xiyou.wangcong@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index efe3e0e..821dee5 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -413,7 +413,7 @@
if (!populated_zone(zone))
need_zonelists_rebuild = 1;
- ret = walk_memory_resource(pfn, nr_pages, &onlined_pages,
+ ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
online_pages_range);
if (ret) {
printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
@@ -705,7 +705,7 @@
static void
offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
{
- walk_memory_resource(start_pfn, end_pfn - start_pfn, NULL,
+ walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
offline_isolated_pages_cb);
}
@@ -731,7 +731,7 @@
long offlined = 0;
int ret;
- ret = walk_memory_resource(start_pfn, end_pfn - start_pfn, &offlined,
+ ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
check_pages_isolated_cb);
if (ret < 0)
offlined = (long)ret;
