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23 October 2021, 00:29:24 UTC
Revision ea0854170c95245a258b386c7a9314399c949fe0 authored by Shaohui Zheng on 02 February 2010, 21:44:16 UTC, committed by Linus Torvalds on 03 February 2010, 02:11:23 UTC 
memory hotplug: fix a bug on /dev/mem for 64-bit kernels
 
Newly added memory can not be accessed via /dev/mem, because we do not
update the variables high_memory, max_pfn and max_low_pfn.

Add a function update_end_of_memory_vars() to update these variables for
64-bit kernels.

[akpm@linux-foundation.org: simplify comment]
Signed-off-by: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Li Haicheng <haicheng.li@intel.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent a225a5c
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Tip revision: ea0854170c95245a258b386c7a9314399c949fe0 authored by Shaohui Zheng on 02 February 2010, 21:44:16 UTC
memory hotplug: fix a bug on /dev/mem for 64-bit kernels
Tip revision: ea08541
reciprocal_div.c 
#include <asm/div64.h>
#include <linux/reciprocal_div.h>

u32 reciprocal_value(u32 k)
{
	u64 val = (1LL << 32) + (k - 1);
	do_div(val, k);
	return (u32)val;
}
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