/* * Handle the memory map. * The functions here do the job until bootmem takes over. * * Getting sanitize_e820_map() in sync with i386 version by applying change: * - Provisions for empty E820 memory regions (reported by certain BIOSes). * Alex Achenbach <xela@slit.de>, December 2002. * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> * */ #include <linux/kernel.h> #include <linux/types.h> #include <linux/init.h> #include <linux/bootmem.h> #include <linux/ioport.h> #include <linux/string.h> #include <linux/kexec.h> #include <linux/module.h> #include <linux/mm.h> #include <linux/suspend.h> #include <linux/pfn.h> #include <asm/pgtable.h> #include <asm/page.h> #include <asm/e820.h> #include <asm/proto.h> #include <asm/setup.h> #include <asm/sections.h> #include <asm/kdebug.h> struct e820map e820; /* * PFN of last memory page. */ unsigned long end_pfn; /* * end_pfn only includes RAM, while end_pfn_map includes all e820 entries. * The direct mapping extends to end_pfn_map, so that we can directly access * apertures, ACPI and other tables without having to play with fixmaps. */ unsigned long end_pfn_map; /* * Last pfn which the user wants to use. */ static unsigned long __initdata end_user_pfn = MAXMEM>>PAGE_SHIFT; /* Check for some hardcoded bad areas that early boot is not allowed to touch */ static inline int bad_addr(unsigned long *addrp, unsigned long size) { unsigned long addr = *addrp, last = addr + size; /* various gunk below that needed for SMP startup */ if (addr < 0x8000) { *addrp = PAGE_ALIGN(0x8000); return 1; } /* direct mapping tables of the kernel */ if (last >= table_start<<PAGE_SHIFT && addr < table_end<<PAGE_SHIFT) { *addrp = PAGE_ALIGN(table_end << PAGE_SHIFT); return 1; } /* initrd */ #ifdef CONFIG_BLK_DEV_INITRD if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) { unsigned long ramdisk_image = boot_params.hdr.ramdisk_image; unsigned long ramdisk_size = boot_params.hdr.ramdisk_size; unsigned long ramdisk_end = ramdisk_image+ramdisk_size; if (last >= ramdisk_image && addr < ramdisk_end) { *addrp = PAGE_ALIGN(ramdisk_end); return 1; } } #endif /* kernel code */ if (last >= __pa_symbol(&_text) && addr < __pa_symbol(&_end)) { *addrp = PAGE_ALIGN(__pa_symbol(&_end)); return 1; } if (last >= ebda_addr && addr < ebda_addr + ebda_size) { *addrp = PAGE_ALIGN(ebda_addr + ebda_size); return 1; } #ifdef CONFIG_NUMA /* NUMA memory to node map */ if (last >= nodemap_addr && addr < nodemap_addr + nodemap_size) { *addrp = nodemap_addr + nodemap_size; return 1; } #endif /* XXX ramdisk image here? */ return 0; } /* * This function checks if any part of the range <start,end> is mapped * with type. */ int e820_any_mapped(unsigned long start, unsigned long end, unsigned type) { int i; for (i = 0; i < e820.nr_map; i++) { struct e820entry *ei = &e820.map[i]; if (type && ei->type != type) continue; if (ei->addr >= end || ei->addr + ei->size <= start) continue; return 1; } return 0; } EXPORT_SYMBOL_GPL(e820_any_mapped); /* * This function checks if the entire range <start,end> is mapped with type. * * Note: this function only works correct if the e820 table is sorted and * not-overlapping, which is the case */ int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type) { int i; for (i = 0; i < e820.nr_map; i++) { struct e820entry *ei = &e820.map[i]; if (type && ei->type != type) continue; /* is the region (part) in overlap with the current region ?*/ if (ei->addr >= end || ei->addr + ei->size <= start) continue; /* if the region is at the beginning of <start,end> we move * start to the end of the region since it's ok until there */ if (ei->addr <= start) start = ei->addr + ei->size; /* * if start is now at or beyond end, we're done, full * coverage */ if (start >= end) return 1; } return 0; } /* * Find a free area in a specific range. */ unsigned long __init find_e820_area(unsigned long start, unsigned long end, unsigned size) { int i; for (i = 0; i < e820.nr_map; i++) { struct e820entry *ei = &e820.map[i]; unsigned long addr = ei->addr, last; if (ei->type != E820_RAM) continue; if (addr < start) addr = start; if (addr > ei->addr + ei->size) continue; while (bad_addr(&addr, size) && addr+size <= ei->addr+ei->size) ; last = PAGE_ALIGN(addr) + size; if (last > ei->addr + ei->size) continue; if (last > end) continue; return addr; } return -1UL; } /* * Find the highest page frame number we have available */ unsigned long __init e820_end_of_ram(void) { unsigned long end_pfn; end_pfn = find_max_pfn_with_active_regions(); if (end_pfn > end_pfn_map) end_pfn_map = end_pfn; if (end_pfn_map > MAXMEM>>PAGE_SHIFT) end_pfn_map = MAXMEM>>PAGE_SHIFT; if (end_pfn > end_user_pfn) end_pfn = end_user_pfn; if (end_pfn > end_pfn_map) end_pfn = end_pfn_map; printk(KERN_INFO "end_pfn_map = %lu\n", end_pfn_map); return end_pfn; } /* * Mark e820 reserved areas as busy for the resource manager. */ void __init e820_reserve_resources(struct resource *code_resource, struct resource *data_resource, struct resource *bss_resource) { int i; for (i = 0; i < e820.nr_map; i++) { struct resource *res; res = alloc_bootmem_low(sizeof(struct resource)); switch (e820.map[i].type) { case E820_RAM: res->name = "System RAM"; break; case E820_ACPI: res->name = "ACPI Tables"; break; case E820_NVS: res->name = "ACPI Non-volatile Storage"; break; default: res->name = "reserved"; } res->start = e820.map[i].addr; res->end = res->start + e820.map[i].size - 1; res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; request_resource(&iomem_resource, res); if (e820.map[i].type == E820_RAM) { /* * We don't know which RAM region contains kernel data, * so we try it repeatedly and let the resource manager * test it. */ request_resource(res, code_resource); request_resource(res, data_resource); request_resource(res, bss_resource); #ifdef CONFIG_KEXEC if (crashk_res.start != crashk_res.end) request_resource(res, &crashk_res); #endif } } } /* * Find the ranges of physical addresses that do not correspond to * e820 RAM areas and mark the corresponding pages as nosave for software * suspend and suspend to RAM. * * This function requires the e820 map to be sorted and without any * overlapping entries and assumes the first e820 area to be RAM. */ void __init e820_mark_nosave_regions(void) { int i; unsigned long paddr; paddr = round_down(e820.map[0].addr + e820.map[0].size, PAGE_SIZE); for (i = 1; i < e820.nr_map; i++) { struct e820entry *ei = &e820.map[i]; if (paddr < ei->addr) register_nosave_region(PFN_DOWN(paddr), PFN_UP(ei->addr)); paddr = round_down(ei->addr + ei->size, PAGE_SIZE); if (ei->type != E820_RAM) register_nosave_region(PFN_UP(ei->addr), PFN_DOWN(paddr)); if (paddr >= (end_pfn << PAGE_SHIFT)) break; } } /* * Finds an active region in the address range from start_pfn to end_pfn and * returns its range in ei_startpfn and ei_endpfn for the e820 entry. */ static int __init e820_find_active_region(const struct e820entry *ei, unsigned long start_pfn, unsigned long end_pfn, unsigned long *ei_startpfn, unsigned long *ei_endpfn) { *ei_startpfn = round_up(ei->addr, PAGE_SIZE) >> PAGE_SHIFT; *ei_endpfn = round_down(ei->addr + ei->size, PAGE_SIZE) >> PAGE_SHIFT; /* Skip map entries smaller than a page */ if (*ei_startpfn >= *ei_endpfn) return 0; /* Check if end_pfn_map should be updated */ if (ei->type != E820_RAM && *ei_endpfn > end_pfn_map) end_pfn_map = *ei_endpfn; /* Skip if map is outside the node */ if (ei->type != E820_RAM || *ei_endpfn <= start_pfn || *ei_startpfn >= end_pfn) return 0; /* Check for overlaps */ if (*ei_startpfn < start_pfn) *ei_startpfn = start_pfn; if (*ei_endpfn > end_pfn) *ei_endpfn = end_pfn; /* Obey end_user_pfn to save on memmap */ if (*ei_startpfn >= end_user_pfn) return 0; if (*ei_endpfn > end_user_pfn) *ei_endpfn = end_user_pfn; return 1; } /* Walk the e820 map and register active regions within a node */ void __init e820_register_active_regions(int nid, unsigned long start_pfn, unsigned long end_pfn) { unsigned long ei_startpfn; unsigned long ei_endpfn; int i; for (i = 0; i < e820.nr_map; i++) if (e820_find_active_region(&e820.map[i], start_pfn, end_pfn, &ei_startpfn, &ei_endpfn)) add_active_range(nid, ei_startpfn, ei_endpfn); } /* * Add a memory region to the kernel e820 map. */ void __init add_memory_region(unsigned long start, unsigned long size, int type) { int x = e820.nr_map; if (x == E820MAX) { printk(KERN_ERR "Ooops! Too many entries in the memory map!\n"); return; } e820.map[x].addr = start; e820.map[x].size = size; e820.map[x].type = type; e820.nr_map++; } /* * Find the hole size (in bytes) in the memory range. * @start: starting address of the memory range to scan * @end: ending address of the memory range to scan */ unsigned long __init e820_hole_size(unsigned long start, unsigned long end) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long end_pfn = end >> PAGE_SHIFT; unsigned long ei_startpfn, ei_endpfn, ram = 0; int i; for (i = 0; i < e820.nr_map; i++) { if (e820_find_active_region(&e820.map[i], start_pfn, end_pfn, &ei_startpfn, &ei_endpfn)) ram += ei_endpfn - ei_startpfn; } return end - start - (ram << PAGE_SHIFT); } static void __init e820_print_map(char *who) { int i; for (i = 0; i < e820.nr_map; i++) { printk(KERN_INFO " %s: %016Lx - %016Lx ", who, (unsigned long long) e820.map[i].addr, (unsigned long long) (e820.map[i].addr + e820.map[i].size)); switch (e820.map[i].type) { case E820_RAM: printk(KERN_CONT "(usable)\n"); break; case E820_RESERVED: printk(KERN_CONT "(reserved)\n"); break; case E820_ACPI: printk(KERN_CONT "(ACPI data)\n"); break; case E820_NVS: printk(KERN_CONT "(ACPI NVS)\n"); break; default: printk(KERN_CONT "type %u\n", e820.map[i].type); break; } } } /* * Sanitize the BIOS e820 map. * * Some e820 responses include overlapping entries. The following * replaces the original e820 map with a new one, removing overlaps. * */ static int __init sanitize_e820_map(struct e820entry *biosmap, char *pnr_map) { struct change_member { struct e820entry *pbios; /* pointer to original bios entry */ unsigned long long addr; /* address for this change point */ }; static struct change_member change_point_list[2*E820MAX] __initdata; static struct change_member *change_point[2*E820MAX] __initdata; static struct e820entry *overlap_list[E820MAX] __initdata; static struct e820entry new_bios[E820MAX] __initdata; struct change_member *change_tmp; unsigned long current_type, last_type; unsigned long long last_addr; int chgidx, still_changing; int overlap_entries; int new_bios_entry; int old_nr, new_nr, chg_nr; int i; /* Visually we're performing the following (1,2,3,4 = memory types)... Sample memory map (w/overlaps): ____22__________________ ______________________4_ ____1111________________ _44_____________________ 11111111________________ ____________________33__ ___________44___________ __________33333_________ ______________22________ ___________________2222_ _________111111111______ _____________________11_ _________________4______ Sanitized equivalent (no overlap): 1_______________________ _44_____________________ ___1____________________ ____22__________________ ______11________________ _________1______________ __________3_____________ ___________44___________ _____________33_________ _______________2________ ________________1_______ _________________4______ ___________________2____ ____________________33__ ______________________4_ */ /* if there's only one memory region, don't bother */ if (*pnr_map < 2) return -1; old_nr = *pnr_map; /* bail out if we find any unreasonable addresses in bios map */ for (i = 0; i < old_nr; i++) if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) return -1; /* create pointers for initial change-point information (for sorting) */ for (i = 0; i < 2 * old_nr; i++) change_point[i] = &change_point_list[i]; /* record all known change-points (starting and ending addresses), omitting those that are for empty memory regions */ chgidx = 0; for (i = 0; i < old_nr; i++) { if (biosmap[i].size != 0) { change_point[chgidx]->addr = biosmap[i].addr; change_point[chgidx++]->pbios = &biosmap[i]; change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size; change_point[chgidx++]->pbios = &biosmap[i]; } } chg_nr = chgidx; /* sort change-point list by memory addresses (low -> high) */ still_changing = 1; while (still_changing) { still_changing = 0; for (i = 1; i < chg_nr; i++) { unsigned long long curaddr, lastaddr; unsigned long long curpbaddr, lastpbaddr; curaddr = change_point[i]->addr; lastaddr = change_point[i - 1]->addr; curpbaddr = change_point[i]->pbios->addr; lastpbaddr = change_point[i - 1]->pbios->addr; /* * swap entries, when: * * curaddr > lastaddr or * curaddr == lastaddr and curaddr == curpbaddr and * lastaddr != lastpbaddr */ if (curaddr < lastaddr || (curaddr == lastaddr && curaddr == curpbaddr && lastaddr != lastpbaddr)) { change_tmp = change_point[i]; change_point[i] = change_point[i-1]; change_point[i-1] = change_tmp; still_changing = 1; } } } /* create a new bios memory map, removing overlaps */ overlap_entries = 0; /* number of entries in the overlap table */ new_bios_entry = 0; /* index for creating new bios map entries */ last_type = 0; /* start with undefined memory type */ last_addr = 0; /* start with 0 as last starting address */ /* loop through change-points, determining affect on the new bios map */ for (chgidx = 0; chgidx < chg_nr; chgidx++) { /* keep track of all overlapping bios entries */ if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr) { /* * add map entry to overlap list (> 1 entry * implies an overlap) */ overlap_list[overlap_entries++] = change_point[chgidx]->pbios; } else { /* * remove entry from list (order independent, * so swap with last) */ for (i = 0; i < overlap_entries; i++) { if (overlap_list[i] == change_point[chgidx]->pbios) overlap_list[i] = overlap_list[overlap_entries-1]; } overlap_entries--; } /* * if there are overlapping entries, decide which * "type" to use (larger value takes precedence -- * 1=usable, 2,3,4,4+=unusable) */ current_type = 0; for (i = 0; i < overlap_entries; i++) if (overlap_list[i]->type > current_type) current_type = overlap_list[i]->type; /* * continue building up new bios map based on this * information */ if (current_type != last_type) { if (last_type != 0) { new_bios[new_bios_entry].size = change_point[chgidx]->addr - last_addr; /* * move forward only if the new size * was non-zero */ if (new_bios[new_bios_entry].size != 0) /* * no more space left for new * bios entries ? */ if (++new_bios_entry >= E820MAX) break; } if (current_type != 0) { new_bios[new_bios_entry].addr = change_point[chgidx]->addr; new_bios[new_bios_entry].type = current_type; last_addr = change_point[chgidx]->addr; } last_type = current_type; } } /* retain count for new bios entries */ new_nr = new_bios_entry; /* copy new bios mapping into original location */ memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry)); *pnr_map = new_nr; return 0; } /* * Copy the BIOS e820 map into a safe place. * * Sanity-check it while we're at it.. * * If we're lucky and live on a modern system, the setup code * will have given us a memory map that we can use to properly * set up memory. If we aren't, we'll fake a memory map. */ static int __init copy_e820_map(struct e820entry *biosmap, int nr_map) { /* Only one memory region (or negative)? Ignore it */ if (nr_map < 2) return -1; do { unsigned long start = biosmap->addr; unsigned long size = biosmap->size; unsigned long end = start + size; unsigned long type = biosmap->type; /* Overflow in 64 bits? Ignore the memory map. */ if (start > end) return -1; add_memory_region(start, size, type); } while (biosmap++, --nr_map); return 0; } static void early_panic(char *msg) { early_printk(msg); panic(msg); } void __init setup_memory_region(void) { /* * Try to copy the BIOS-supplied E820-map. * * Otherwise fake a memory map; one section from 0k->640k, * the next section from 1mb->appropriate_mem_k */ sanitize_e820_map(boot_params.e820_map, &boot_params.e820_entries); if (copy_e820_map(boot_params.e820_map, boot_params.e820_entries) < 0) early_panic("Cannot find a valid memory map"); printk(KERN_INFO "BIOS-provided physical RAM map:\n"); e820_print_map("BIOS-e820"); } static int __init parse_memopt(char *p) { if (!p) return -EINVAL; end_user_pfn = memparse(p, &p); end_user_pfn >>= PAGE_SHIFT; return 0; } early_param("mem", parse_memopt); static int userdef __initdata; static int __init parse_memmap_opt(char *p) { char *oldp; unsigned long long start_at, mem_size; if (!strcmp(p, "exactmap")) { #ifdef CONFIG_CRASH_DUMP /* * If we are doing a crash dump, we still need to know * the real mem size before original memory map is * reset. */ e820_register_active_regions(0, 0, -1UL); saved_max_pfn = e820_end_of_ram(); remove_all_active_ranges(); #endif end_pfn_map = 0; e820.nr_map = 0; userdef = 1; return 0; } oldp = p; mem_size = memparse(p, &p); if (p == oldp) return -EINVAL; if (*p == '@') { start_at = memparse(p+1, &p); add_memory_region(start_at, mem_size, E820_RAM); } else if (*p == '#') { start_at = memparse(p+1, &p); add_memory_region(start_at, mem_size, E820_ACPI); } else if (*p == '$') { start_at = memparse(p+1, &p); add_memory_region(start_at, mem_size, E820_RESERVED); } else { end_user_pfn = (mem_size >> PAGE_SHIFT); } return *p == '\0' ? 0 : -EINVAL; } early_param("memmap", parse_memmap_opt); void __init finish_e820_parsing(void) { if (userdef) { printk(KERN_INFO "user-defined physical RAM map:\n"); e820_print_map("user"); } } unsigned long pci_mem_start = 0xaeedbabe; EXPORT_SYMBOL(pci_mem_start); /* * Search for the biggest gap in the low 32 bits of the e820 * memory space. We pass this space to PCI to assign MMIO resources * for hotplug or unconfigured devices in. * Hopefully the BIOS let enough space left. */ __init void e820_setup_gap(void) { unsigned long gapstart, gapsize, round; unsigned long last; int i; int found = 0; last = 0x100000000ull; gapstart = 0x10000000; gapsize = 0x400000; i = e820.nr_map; while (--i >= 0) { unsigned long long start = e820.map[i].addr; unsigned long long end = start + e820.map[i].size; /* * Since "last" is at most 4GB, we know we'll * fit in 32 bits if this condition is true */ if (last > end) { unsigned long gap = last - end; if (gap > gapsize) { gapsize = gap; gapstart = end; found = 1; } } if (start < last) last = start; } if (!found) { gapstart = (end_pfn << PAGE_SHIFT) + 1024*1024; printk(KERN_ERR "PCI: Warning: Cannot find a gap in the 32bit " "address range\n" KERN_ERR "PCI: Unassigned devices with 32bit resource " "registers may break!\n"); } /* * See how much we want to round up: start off with * rounding to the next 1MB area. */ round = 0x100000; while ((gapsize >> 4) > round) round += round; /* Fun with two's complement */ pci_mem_start = (gapstart + round) & -round; printk(KERN_INFO "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n", pci_mem_start, gapstart, gapsize); } int __init arch_get_ram_range(int slot, u64 *addr, u64 *size) { int i; if (slot < 0 || slot >= e820.nr_map) return -1; for (i = slot; i < e820.nr_map; i++) { if (e820.map[i].type != E820_RAM) continue; break; } if (i == e820.nr_map || e820.map[i].addr > (max_pfn << PAGE_SHIFT)) return -1; *addr = e820.map[i].addr; *size = min_t(u64, e820.map[i].size + e820.map[i].addr, max_pfn << PAGE_SHIFT) - *addr; return i + 1; }