diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 722a74161246318ac8ca5ae008b61641076a7bd8..766087781ecd6a7ae52b2843cb58c22fc678a8fb 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1640,15 +1640,30 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
that the amount of memory usable for all allocations
is not too small.
+ movablemem_map=acpi
+ [KNL,X86,IA-64,PPC] This parameter is similar to
+ memmap except it specifies the memory map of
+ ZONE_MOVABLE.
+ This option inform the kernel to use Hot Pluggable bit
+ in flags from SRAT from ACPI BIOS to determine which
+ memory devices could be hotplugged. The corresponding
+ memory ranges will be set as ZONE_MOVABLE.
+ NOTE: Whatever node the kernel resides in will always
+ be un-hotpluggable.
+
movablemem_map=nn[KMG]@ss[KMG]
[KNL,X86,IA-64,PPC] This parameter is similar to
memmap except it specifies the memory map of
ZONE_MOVABLE.
- If more areas are all within one node, then from
- lowest ss to the end of the node will be ZONE_MOVABLE.
- If an area covers two or more nodes, the area from
- ss to the end of the 1st node will be ZONE_MOVABLE,
- and all the rest nodes will only have ZONE_MOVABLE.
+ If user specifies memory ranges, the info in SRAT will
+ be ingored. And it works like the following:
+ - If more ranges are all within one node, then from
+ lowest ss to the end of the node will be ZONE_MOVABLE.
+ - If a range is within a node, then from ss to the end
+ of the node will be ZONE_MOVABLE.
+ - If a range covers two or more nodes, then from ss to
+ the end of the 1st node will be ZONE_MOVABLE, and all
+ the rest nodes will only have ZONE_MOVABLE.
If memmap is specified at the same time, the
movablemem_map will be limited within the memmap
areas. If kernelcore or movablecore is also specified,
@@ -1656,6 +1671,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
satisfied. So the administrator should be careful that
the amount of movablemem_map areas are not too large.
Otherwise kernel won't have enough memory to start.
+ NOTE: We don't stop users specifying the node the
+ kernel resides in as hotpluggable so that this
+ option can be used as a workaround of firmware
+ bugs.
MTD_Partition= [MTD]
Format: <name>,<region-number>,<size>,<offset>
diff --git a/arch/x86/mm/srat.c b/arch/x86/mm/srat.c
index 3e90039e52e075f9f6bc117a1f493ea0de697209..79836d01f78957639fd181102bf54756966f8f71 100644
--- a/arch/x86/mm/srat.c
+++ b/arch/x86/mm/srat.c
@@ -142,16 +142,72 @@ static inline int save_add_info(void) {return 0;}
#endif
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
-static void __init handle_movablemem(int node, u64 start, u64 end)
+static void __init
+handle_movablemem(int node, u64 start, u64 end, u32 hotpluggable)
{
- int overlap;
+ int overlap, i;
unsigned long start_pfn, end_pfn;
start_pfn = PFN_DOWN(start);
end_pfn = PFN_UP(end);
/*
- * For movablecore_map=nn[KMG]@ss[KMG]:
+ * For movablemem_map=acpi:
+ *
+ * SRAT: |_____| |_____| |_________| |_________| ......
+ * node id: 0 1 1 2
+ * hotpluggable: n y y n
+ * movablemem_map: |_____| |_________|
+ *
+ * Using movablemem_map, we can prevent memblock from allocating memory
+ * on ZONE_MOVABLE at boot time.
+ *
+ * Before parsing SRAT, memblock has already reserve some memory ranges
+ * for other purposes, such as for kernel image. We cannot prevent
+ * kernel from using these memory, so we need to exclude these memory
+ * even if it is hotpluggable.
+ * Furthermore, to ensure the kernel has enough memory to boot, we make
+ * all the memory on the node which the kernel resides in
+ * un-hotpluggable.
+ */
+ if (hotpluggable && movablemem_map.acpi) {
+ /* Exclude ranges reserved by memblock. */
+ struct memblock_type *rgn = &memblock.reserved;
+
+ for (i = 0; i < rgn->cnt; i++) {
+ if (end <= rgn->regions[i].base ||
+ start >= rgn->regions[i].base +
+ rgn->regions[i].size)
+ continue;
+
+ /*
+ * If the memory range overlaps the memory reserved by
+ * memblock, then the kernel resides in this node.
+ */
+ node_set(node, movablemem_map.numa_nodes_kernel);
+
+ goto out;
+ }
+
+ /*
+ * If the kernel resides in this node, then the whole node
+ * should not be hotpluggable.
+ */
+ if (node_isset(node, movablemem_map.numa_nodes_kernel))
+ goto out;
+
+ insert_movablemem_map(start_pfn, end_pfn);
+
+ /*
+ * numa_nodes_hotplug nodemask represents which nodes are put
+ * into movablemem_map.map[].
+ */
+ node_set(node, movablemem_map.numa_nodes_hotplug);
+ goto out;
+ }
+
+ /*
+ * For movablemem_map=nn[KMG]@ss[KMG]:
*
* SRAT: |_____| |_____| |_________| |_________| ......
* node id: 0 1 1 2
@@ -160,6 +216,8 @@ static void __init handle_movablemem(int node, u64 start, u64 end)
*
* Using movablemem_map, we can prevent memblock from allocating memory
* on ZONE_MOVABLE at boot time.
+ *
+ * NOTE: In this case, SRAT info will be ingored.
*/
overlap = movablemem_map_overlap(start_pfn, end_pfn);
if (overlap >= 0) {
@@ -187,9 +245,12 @@ static void __init handle_movablemem(int node, u64 start, u64 end)
*/
insert_movablemem_map(start_pfn, end_pfn);
}
+out:
+ return;
}
#else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
-static inline void handle_movablemem(int node, u64 start, u64 end)
+static inline void
+handle_movablemem(int node, u64 start, u64 end, u32 hotpluggable)
{
}
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
@@ -234,7 +295,7 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
(unsigned long long) start, (unsigned long long) end - 1,
hotpluggable ? "Hot Pluggable": "");
- handle_movablemem(node, start, end);
+ handle_movablemem(node, start, end, hotpluggable);
return 0;
out_err_bad_srat:
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 4d7377a1d084787f2cc017ad2781657aa28432ee..72a42c0fa633b5a886aa3959ab8be750497a7741 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1366,9 +1366,11 @@ struct movablemem_entry {
};
struct movablemem_map {
+ bool acpi; /* true if using SRAT info */
int nr_map;
struct movablemem_entry map[MOVABLEMEM_MAP_MAX];
nodemask_t numa_nodes_hotplug; /* on which nodes we specify memory */
+ nodemask_t numa_nodes_kernel; /* on which nodes kernel resides in */
};
extern void __init insert_movablemem_map(unsigned long start_pfn,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 7ea9a003ad57b35fa2afd0f66d519b8d27f45505..a7381be213201c1142749eb93965ffc2cba326f4 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -203,7 +203,10 @@ static unsigned long __meminitdata dma_reserve;
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
/* Movable memory ranges, will also be used by memblock subsystem. */
-struct movablemem_map movablemem_map;
+struct movablemem_map movablemem_map = {
+ .acpi = false,
+ .nr_map = 0,
+};
static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES];
static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES];
@@ -5314,6 +5317,23 @@ static int __init cmdline_parse_movablemem_map(char *p)
if (!p)
goto err;
+ if (!strcmp(p, "acpi"))
+ movablemem_map.acpi = true;
+
+ /*
+ * If user decide to use info from BIOS, all the other user specified
+ * ranges will be ingored.
+ */
+ if (movablemem_map.acpi) {
+ if (movablemem_map.nr_map) {
+ memset(movablemem_map.map, 0,
+ sizeof(struct movablemem_entry)
+ * movablemem_map.nr_map);
+ movablemem_map.nr_map = 0;
+ }
+ return 0;
+ }
+
oldp = p;
mem_size = memparse(p, &p);
if (p == oldp)