/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * This file contains NUMA specific variables and functions which can * be split away from DISCONTIGMEM and are used on NUMA machines with * contiguous memory. * * 2002/08/07 Erich Focht <efocht@ess.nec.de> */ #include <linux/cpu.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/node.h> #include <linux/init.h> #include <linux/bootmem.h> #include <linux/module.h> #include <asm/mmzone.h> #include <asm/numa.h> /* * The following structures are usually initialized by ACPI or * similar mechanisms and describe the NUMA characteristics of the machine. */ int num_node_memblks; struct node_memblk_s node_memblk[NR_NODE_MEMBLKS]; struct node_cpuid_s node_cpuid[NR_CPUS]; /* * This is a matrix with "distances" between nodes, they should be * proportional to the memory access latency ratios. */ u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES]; /* Identify which cnode a physical address resides on */ int paddr_to_nid(unsigned long paddr) { int i; for (i = 0; i < num_node_memblks; i++) if (paddr >= node_memblk[i].start_paddr && paddr < node_memblk[i].start_paddr + node_memblk[i].size) break; return (i < num_node_memblks) ? node_memblk[i].nid : (num_node_memblks ? -1 : 0); } #if defined(CONFIG_SPARSEMEM) && defined(CONFIG_NUMA) /* * Because of holes evaluate on section limits. * If the section of memory exists, then return the node where the section * resides. Otherwise return node 0 as the default. This is used by * SPARSEMEM to allocate the SPARSEMEM sectionmap on the NUMA node where * the section resides. */ int early_pfn_to_nid(unsigned long pfn) { int i, section = pfn >> PFN_SECTION_SHIFT, ssec, esec; for (i = 0; i < num_node_memblks; i++) { ssec = node_memblk[i].start_paddr >> PA_SECTION_SHIFT; esec = (node_memblk[i].start_paddr + node_memblk[i].size + ((1L << PA_SECTION_SHIFT) - 1)) >> PA_SECTION_SHIFT; if (section >= ssec && section < esec) return node_memblk[i].nid; } return 0; } #ifdef CONFIG_MEMORY_HOTPLUG /* * SRAT information is stored in node_memblk[], then we can use SRAT * information at memory-hot-add if necessary. */ int memory_add_physaddr_to_nid(u64 addr) { int nid = paddr_to_nid(addr); if (nid < 0) return 0; return nid; } EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); #endif #endif