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-rw-r--r--arch/x86/mm/srat_64.c566
1 files changed, 566 insertions, 0 deletions
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
new file mode 100644
index 000000000000..acdf03e19146
--- /dev/null
+++ b/arch/x86/mm/srat_64.c
@@ -0,0 +1,566 @@
+/*
+ * ACPI 3.0 based NUMA setup
+ * Copyright 2004 Andi Kleen, SuSE Labs.
+ *
+ * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
+ *
+ * Called from acpi_numa_init while reading the SRAT and SLIT tables.
+ * Assumes all memory regions belonging to a single proximity domain
+ * are in one chunk. Holes between them will be included in the node.
+ */
+
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/mmzone.h>
+#include <linux/bitmap.h>
+#include <linux/module.h>
+#include <linux/topology.h>
+#include <linux/bootmem.h>
+#include <linux/mm.h>
+#include <asm/proto.h>
+#include <asm/numa.h>
+#include <asm/e820.h>
+
+int acpi_numa __initdata;
+
+static struct acpi_table_slit *acpi_slit;
+
+static nodemask_t nodes_parsed __initdata;
+static struct bootnode nodes[MAX_NUMNODES] __initdata;
+static struct bootnode nodes_add[MAX_NUMNODES];
+static int found_add_area __initdata;
+int hotadd_percent __initdata = 0;
+
+/* Too small nodes confuse the VM badly. Usually they result
+ from BIOS bugs. */
+#define NODE_MIN_SIZE (4*1024*1024)
+
+static __init int setup_node(int pxm)
+{
+ return acpi_map_pxm_to_node(pxm);
+}
+
+static __init int conflicting_nodes(unsigned long start, unsigned long end)
+{
+ int i;
+ for_each_node_mask(i, nodes_parsed) {
+ struct bootnode *nd = &nodes[i];
+ if (nd->start == nd->end)
+ continue;
+ if (nd->end > start && nd->start < end)
+ return i;
+ if (nd->end == end && nd->start == start)
+ return i;
+ }
+ return -1;
+}
+
+static __init void cutoff_node(int i, unsigned long start, unsigned long end)
+{
+ struct bootnode *nd = &nodes[i];
+
+ if (found_add_area)
+ return;
+
+ if (nd->start < start) {
+ nd->start = start;
+ if (nd->end < nd->start)
+ nd->start = nd->end;
+ }
+ if (nd->end > end) {
+ nd->end = end;
+ if (nd->start > nd->end)
+ nd->start = nd->end;
+ }
+}
+
+static __init void bad_srat(void)
+{
+ int i;
+ printk(KERN_ERR "SRAT: SRAT not used.\n");
+ acpi_numa = -1;
+ found_add_area = 0;
+ for (i = 0; i < MAX_LOCAL_APIC; i++)
+ apicid_to_node[i] = NUMA_NO_NODE;
+ for (i = 0; i < MAX_NUMNODES; i++)
+ nodes_add[i].start = nodes[i].end = 0;
+ remove_all_active_ranges();
+}
+
+static __init inline int srat_disabled(void)
+{
+ return numa_off || acpi_numa < 0;
+}
+
+/*
+ * A lot of BIOS fill in 10 (= no distance) everywhere. This messes
+ * up the NUMA heuristics which wants the local node to have a smaller
+ * distance than the others.
+ * Do some quick checks here and only use the SLIT if it passes.
+ */
+static __init int slit_valid(struct acpi_table_slit *slit)
+{
+ int i, j;
+ int d = slit->locality_count;
+ for (i = 0; i < d; i++) {
+ for (j = 0; j < d; j++) {
+ u8 val = slit->entry[d*i + j];
+ if (i == j) {
+ if (val != LOCAL_DISTANCE)
+ return 0;
+ } else if (val <= LOCAL_DISTANCE)
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/* Callback for SLIT parsing */
+void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
+{
+ if (!slit_valid(slit)) {
+ printk(KERN_INFO "ACPI: SLIT table looks invalid. Not used.\n");
+ return;
+ }
+ acpi_slit = slit;
+}
+
+/* Callback for Proximity Domain -> LAPIC mapping */
+void __init
+acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa)
+{
+ int pxm, node;
+ if (srat_disabled())
+ return;
+ if (pa->header.length != sizeof(struct acpi_srat_cpu_affinity)) {
+ bad_srat();
+ return;
+ }
+ if ((pa->flags & ACPI_SRAT_CPU_ENABLED) == 0)
+ return;
+ pxm = pa->proximity_domain_lo;
+ node = setup_node(pxm);
+ if (node < 0) {
+ printk(KERN_ERR "SRAT: Too many proximity domains %x\n", pxm);
+ bad_srat();
+ return;
+ }
+ apicid_to_node[pa->apic_id] = node;
+ acpi_numa = 1;
+ printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n",
+ pxm, pa->apic_id, node);
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG_RESERVE
+/*
+ * Protect against too large hotadd areas that would fill up memory.
+ */
+static int hotadd_enough_memory(struct bootnode *nd)
+{
+ static unsigned long allocated;
+ static unsigned long last_area_end;
+ unsigned long pages = (nd->end - nd->start) >> PAGE_SHIFT;
+ long mem = pages * sizeof(struct page);
+ unsigned long addr;
+ unsigned long allowed;
+ unsigned long oldpages = pages;
+
+ if (mem < 0)
+ return 0;
+ allowed = (end_pfn - absent_pages_in_range(0, end_pfn)) * PAGE_SIZE;
+ allowed = (allowed / 100) * hotadd_percent;
+ if (allocated + mem > allowed) {
+ unsigned long range;
+ /* Give them at least part of their hotadd memory upto hotadd_percent
+ It would be better to spread the limit out
+ over multiple hotplug areas, but that is too complicated
+ right now */
+ if (allocated >= allowed)
+ return 0;
+ range = allowed - allocated;
+ pages = (range / PAGE_SIZE);
+ mem = pages * sizeof(struct page);
+ nd->end = nd->start + range;
+ }
+ /* Not completely fool proof, but a good sanity check */
+ addr = find_e820_area(last_area_end, end_pfn<<PAGE_SHIFT, mem);
+ if (addr == -1UL)
+ return 0;
+ if (pages != oldpages)
+ printk(KERN_NOTICE "SRAT: Hotadd area limited to %lu bytes\n",
+ pages << PAGE_SHIFT);
+ last_area_end = addr + mem;
+ allocated += mem;
+ return 1;
+}
+
+static int update_end_of_memory(unsigned long end)
+{
+ found_add_area = 1;
+ if ((end >> PAGE_SHIFT) > end_pfn)
+ end_pfn = end >> PAGE_SHIFT;
+ return 1;
+}
+
+static inline int save_add_info(void)
+{
+ return hotadd_percent > 0;
+}
+#else
+int update_end_of_memory(unsigned long end) {return -1;}
+static int hotadd_enough_memory(struct bootnode *nd) {return 1;}
+#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
+static inline int save_add_info(void) {return 1;}
+#else
+static inline int save_add_info(void) {return 0;}
+#endif
+#endif
+/*
+ * Update nodes_add and decide if to include add are in the zone.
+ * Both SPARSE and RESERVE need nodes_add infomation.
+ * This code supports one contigious hot add area per node.
+ */
+static int reserve_hotadd(int node, unsigned long start, unsigned long end)
+{
+ unsigned long s_pfn = start >> PAGE_SHIFT;
+ unsigned long e_pfn = end >> PAGE_SHIFT;
+ int ret = 0, changed = 0;
+ struct bootnode *nd = &nodes_add[node];
+
+ /* I had some trouble with strange memory hotadd regions breaking
+ the boot. Be very strict here and reject anything unexpected.
+ If you want working memory hotadd write correct SRATs.
+
+ The node size check is a basic sanity check to guard against
+ mistakes */
+ if ((signed long)(end - start) < NODE_MIN_SIZE) {
+ printk(KERN_ERR "SRAT: Hotplug area too small\n");
+ return -1;
+ }
+
+ /* This check might be a bit too strict, but I'm keeping it for now. */
+ if (absent_pages_in_range(s_pfn, e_pfn) != e_pfn - s_pfn) {
+ printk(KERN_ERR
+ "SRAT: Hotplug area %lu -> %lu has existing memory\n",
+ s_pfn, e_pfn);
+ return -1;
+ }
+
+ if (!hotadd_enough_memory(&nodes_add[node])) {
+ printk(KERN_ERR "SRAT: Hotplug area too large\n");
+ return -1;
+ }
+
+ /* Looks good */
+
+ if (nd->start == nd->end) {
+ nd->start = start;
+ nd->end = end;
+ changed = 1;
+ } else {
+ if (nd->start == end) {
+ nd->start = start;
+ changed = 1;
+ }
+ if (nd->end == start) {
+ nd->end = end;
+ changed = 1;
+ }
+ if (!changed)
+ printk(KERN_ERR "SRAT: Hotplug zone not continuous. Partly ignored\n");
+ }
+
+ ret = update_end_of_memory(nd->end);
+
+ if (changed)
+ printk(KERN_INFO "SRAT: hot plug zone found %Lx - %Lx\n", nd->start, nd->end);
+ return ret;
+}
+
+/* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
+void __init
+acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
+{
+ struct bootnode *nd, oldnode;
+ unsigned long start, end;
+ int node, pxm;
+ int i;
+
+ if (srat_disabled())
+ return;
+ if (ma->header.length != sizeof(struct acpi_srat_mem_affinity)) {
+ bad_srat();
+ return;
+ }
+ if ((ma->flags & ACPI_SRAT_MEM_ENABLED) == 0)
+ return;
+
+ if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) && !save_add_info())
+ return;
+ start = ma->base_address;
+ end = start + ma->length;
+ pxm = ma->proximity_domain;
+ node = setup_node(pxm);
+ if (node < 0) {
+ printk(KERN_ERR "SRAT: Too many proximity domains.\n");
+ bad_srat();
+ return;
+ }
+ i = conflicting_nodes(start, end);
+ if (i == node) {
+ printk(KERN_WARNING
+ "SRAT: Warning: PXM %d (%lx-%lx) overlaps with itself (%Lx-%Lx)\n",
+ pxm, start, end, nodes[i].start, nodes[i].end);
+ } else if (i >= 0) {
+ printk(KERN_ERR
+ "SRAT: PXM %d (%lx-%lx) overlaps with PXM %d (%Lx-%Lx)\n",
+ pxm, start, end, node_to_pxm(i),
+ nodes[i].start, nodes[i].end);
+ bad_srat();
+ return;
+ }
+ nd = &nodes[node];
+ oldnode = *nd;
+ if (!node_test_and_set(node, nodes_parsed)) {
+ nd->start = start;
+ nd->end = end;
+ } else {
+ if (start < nd->start)
+ nd->start = start;
+ if (nd->end < end)
+ nd->end = end;
+ }
+
+ printk(KERN_INFO "SRAT: Node %u PXM %u %Lx-%Lx\n", node, pxm,
+ nd->start, nd->end);
+ e820_register_active_regions(node, nd->start >> PAGE_SHIFT,
+ nd->end >> PAGE_SHIFT);
+ push_node_boundaries(node, nd->start >> PAGE_SHIFT,
+ nd->end >> PAGE_SHIFT);
+
+ if ((ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) &&
+ (reserve_hotadd(node, start, end) < 0)) {
+ /* Ignore hotadd region. Undo damage */
+ printk(KERN_NOTICE "SRAT: Hotplug region ignored\n");
+ *nd = oldnode;
+ if ((nd->start | nd->end) == 0)
+ node_clear(node, nodes_parsed);
+ }
+}
+
+/* Sanity check to catch more bad SRATs (they are amazingly common).
+ Make sure the PXMs cover all memory. */
+static int __init nodes_cover_memory(const struct bootnode *nodes)
+{
+ int i;
+ unsigned long pxmram, e820ram;
+
+ pxmram = 0;
+ for_each_node_mask(i, nodes_parsed) {
+ unsigned long s = nodes[i].start >> PAGE_SHIFT;
+ unsigned long e = nodes[i].end >> PAGE_SHIFT;
+ pxmram += e - s;
+ pxmram -= absent_pages_in_range(s, e);
+ if ((long)pxmram < 0)
+ pxmram = 0;
+ }
+
+ e820ram = end_pfn - absent_pages_in_range(0, end_pfn);
+ /* We seem to lose 3 pages somewhere. Allow a bit of slack. */
+ if ((long)(e820ram - pxmram) >= 1*1024*1024) {
+ printk(KERN_ERR
+ "SRAT: PXMs only cover %luMB of your %luMB e820 RAM. Not used.\n",
+ (pxmram << PAGE_SHIFT) >> 20,
+ (e820ram << PAGE_SHIFT) >> 20);
+ return 0;
+ }
+ return 1;
+}
+
+static void unparse_node(int node)
+{
+ int i;
+ node_clear(node, nodes_parsed);
+ for (i = 0; i < MAX_LOCAL_APIC; i++) {
+ if (apicid_to_node[i] == node)
+ apicid_to_node[i] = NUMA_NO_NODE;
+ }
+}
+
+void __init acpi_numa_arch_fixup(void) {}
+
+/* Use the information discovered above to actually set up the nodes. */
+int __init acpi_scan_nodes(unsigned long start, unsigned long end)
+{
+ int i;
+
+ if (acpi_numa <= 0)
+ return -1;
+
+ /* First clean up the node list */
+ for (i = 0; i < MAX_NUMNODES; i++) {
+ cutoff_node(i, start, end);
+ if ((nodes[i].end - nodes[i].start) < NODE_MIN_SIZE) {
+ unparse_node(i);
+ node_set_offline(i);
+ }
+ }
+
+ if (!nodes_cover_memory(nodes)) {
+ bad_srat();
+ return -1;
+ }
+
+ memnode_shift = compute_hash_shift(nodes, MAX_NUMNODES);
+ if (memnode_shift < 0) {
+ printk(KERN_ERR
+ "SRAT: No NUMA node hash function found. Contact maintainer\n");
+ bad_srat();
+ return -1;
+ }
+
+ node_possible_map = nodes_parsed;
+
+ /* Finally register nodes */
+ for_each_node_mask(i, node_possible_map)
+ setup_node_bootmem(i, nodes[i].start, nodes[i].end);
+ /* Try again in case setup_node_bootmem missed one due
+ to missing bootmem */
+ for_each_node_mask(i, node_possible_map)
+ if (!node_online(i))
+ setup_node_bootmem(i, nodes[i].start, nodes[i].end);
+
+ for (i = 0; i < NR_CPUS; i++) {
+ if (cpu_to_node[i] == NUMA_NO_NODE)
+ continue;
+ if (!node_isset(cpu_to_node[i], node_possible_map))
+ numa_set_node(i, NUMA_NO_NODE);
+ }
+ numa_init_array();
+ return 0;
+}
+
+#ifdef CONFIG_NUMA_EMU
+static int __init find_node_by_addr(unsigned long addr)
+{
+ int ret = NUMA_NO_NODE;
+ int i;
+
+ for_each_node_mask(i, nodes_parsed) {
+ /*
+ * Find the real node that this emulated node appears on. For
+ * the sake of simplicity, we only use a real node's starting
+ * address to determine which emulated node it appears on.
+ */
+ if (addr >= nodes[i].start && addr < nodes[i].end) {
+ ret = i;
+ break;
+ }
+ }
+ return i;
+}
+
+/*
+ * In NUMA emulation, we need to setup proximity domain (_PXM) to node ID
+ * mappings that respect the real ACPI topology but reflect our emulated
+ * environment. For each emulated node, we find which real node it appears on
+ * and create PXM to NID mappings for those fake nodes which mirror that
+ * locality. SLIT will now represent the correct distances between emulated
+ * nodes as a result of the real topology.
+ */
+void __init acpi_fake_nodes(const struct bootnode *fake_nodes, int num_nodes)
+{
+ int i, j;
+ int fake_node_to_pxm_map[MAX_NUMNODES] = {
+ [0 ... MAX_NUMNODES-1] = PXM_INVAL
+ };
+ unsigned char fake_apicid_to_node[MAX_LOCAL_APIC] = {
+ [0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
+ };
+
+ printk(KERN_INFO "Faking PXM affinity for fake nodes on real "
+ "topology.\n");
+ for (i = 0; i < num_nodes; i++) {
+ int nid, pxm;
+
+ nid = find_node_by_addr(fake_nodes[i].start);
+ if (nid == NUMA_NO_NODE)
+ continue;
+ pxm = node_to_pxm(nid);
+ if (pxm == PXM_INVAL)
+ continue;
+ fake_node_to_pxm_map[i] = pxm;
+ /*
+ * For each apicid_to_node mapping that exists for this real
+ * node, it must now point to the fake node ID.
+ */
+ for (j = 0; j < MAX_LOCAL_APIC; j++)
+ if (apicid_to_node[j] == nid)
+ fake_apicid_to_node[j] = i;
+ }
+ for (i = 0; i < num_nodes; i++)
+ __acpi_map_pxm_to_node(fake_node_to_pxm_map[i], i);
+ memcpy(apicid_to_node, fake_apicid_to_node, sizeof(apicid_to_node));
+
+ nodes_clear(nodes_parsed);
+ for (i = 0; i < num_nodes; i++)
+ if (fake_nodes[i].start != fake_nodes[i].end)
+ node_set(i, nodes_parsed);
+ WARN_ON(!nodes_cover_memory(fake_nodes));
+}
+
+static int null_slit_node_compare(int a, int b)
+{
+ return node_to_pxm(a) == node_to_pxm(b);
+}
+#else
+static int null_slit_node_compare(int a, int b)
+{
+ return a == b;
+}
+#endif /* CONFIG_NUMA_EMU */
+
+void __init srat_reserve_add_area(int nodeid)
+{
+ if (found_add_area && nodes_add[nodeid].end) {
+ u64 total_mb;
+
+ printk(KERN_INFO "SRAT: Reserving hot-add memory space "
+ "for node %d at %Lx-%Lx\n",
+ nodeid, nodes_add[nodeid].start, nodes_add[nodeid].end);
+ total_mb = (nodes_add[nodeid].end - nodes_add[nodeid].start)
+ >> PAGE_SHIFT;
+ total_mb *= sizeof(struct page);
+ total_mb >>= 20;
+ printk(KERN_INFO "SRAT: This will cost you %Lu MB of "
+ "pre-allocated memory.\n", (unsigned long long)total_mb);
+ reserve_bootmem_node(NODE_DATA(nodeid), nodes_add[nodeid].start,
+ nodes_add[nodeid].end - nodes_add[nodeid].start);
+ }
+}
+
+int __node_distance(int a, int b)
+{
+ int index;
+
+ if (!acpi_slit)
+ return null_slit_node_compare(a, b) ? LOCAL_DISTANCE :
+ REMOTE_DISTANCE;
+ index = acpi_slit->locality_count * node_to_pxm(a);
+ return acpi_slit->entry[index + node_to_pxm(b)];
+}
+
+EXPORT_SYMBOL(__node_distance);
+
+int memory_add_physaddr_to_nid(u64 start)
+{
+ int i, ret = 0;
+
+ for_each_node(i)
+ if (nodes_add[i].start <= start && nodes_add[i].end > start)
+ ret = i;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
+
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