linux-kernel - [PATCH 03/21] x86, acpi, numa, mem-hotplug: Introduce MEMBLK_HOTPLUGGABLE to reserve hotpluggable memory.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 19 Jul 2013 15:59:16 +0800
From:	Tang Chen <tangchen@...fujitsu.com>
To:	tglx@...utronix.de, mingo@...e.hu, hpa@...or.com,
	akpm@...ux-foundation.org, tj@...nel.org, trenn@...e.de,
	yinghai@...nel.org, jiang.liu@...wei.com, wency@...fujitsu.com,
	laijs@...fujitsu.com, isimatu.yasuaki@...fujitsu.com,
	izumi.taku@...fujitsu.com, mgorman@...e.de, minchan@...nel.org,
	mina86@...a86.com, gong.chen@...ux.intel.com,
	vasilis.liaskovitis@...fitbricks.com, lwoodman@...hat.com,
	riel@...hat.com, jweiner@...hat.com, prarit@...hat.com,
	zhangyanfei@...fujitsu.com, yanghy@...fujitsu.com
Cc:	x86@...nel.org, linux-doc@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	linux-acpi@...r.kernel.org
Subject: [PATCH 03/21] x86, acpi, numa, mem-hotplug: Introduce MEMBLK_HOTPLUGGABLE to reserve hotpluggable memory.

Pages used by the kernel cannot be migrated. As a result, hotpluggable
memory used by the kernel cannot be hot-removed. So for memory
hotplug users, the kernel should not use hotpluggable memory.

Since now we have flags in memblock, we introduce a MEMBLK_HOTPLUGGABLE
flag to mark hotpluggable memory. At the early time, we use memblock to
reserve hotpluggable memory, and mark it with MEMBLK_HOTPLUGGABLE flag.
When the system is up, we free these memory with MEMBLK_HOTPLUGGABLE
flag to the buddy, and arrange them into ZONE_MOVABLE. In this way, the
kernel won't be able to use it.

This patch introduces MEMBLK_HOTPLUGGABLE flag, and an API to reserve
memory with MEMBLK_HOTPLUGGABLE flag. This is a preparation for the
coming patches.

Signed-off-by: Tang Chen <tangchen@...fujitsu.com>
---
 include/linux/memblock.h |    2 ++
 mm/memblock.c            |    6 ++++++
 2 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 93f3453..90b49ee 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -21,6 +21,7 @@
 
 /* Definition of memblock flags. */
 #define MEMBLK_FLAGS_DEFAULT	0x0	/* default flag */
+#define MEMBLK_HOTPLUGGABLE	0x1	/* hotpluggable region */
 
 struct memblock_region {
 	phys_addr_t base;
@@ -61,6 +62,7 @@ int memblock_add(phys_addr_t base, phys_addr_t size);
 int memblock_remove(phys_addr_t base, phys_addr_t size);
 int memblock_free(phys_addr_t base, phys_addr_t size);
 int memblock_reserve(phys_addr_t base, phys_addr_t size);
+int memblock_reserve_hotpluggable(phys_addr_t base, phys_addr_t size, int nid);
 void memblock_trim_memory(phys_addr_t align);
 
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
diff --git a/mm/memblock.c b/mm/memblock.c
index 9e871e9..73fe62d 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -586,6 +586,12 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
 				       MEMBLK_FLAGS_DEFAULT);
 }
 
+int __init_memblock memblock_reserve_hotpluggable(phys_addr_t base,
+						  phys_addr_t size, int nid)
+{
+	return memblock_reserve_region(base, size, nid, MEMBLK_HOTPLUGGABLE);
+}
+
 /**
  * __next_free_mem_range - next function for for_each_free_mem_range()
  * @idx: pointer to u64 loop variable
-- 
1.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/