diff options
Diffstat (limited to 'arch/x86/kernel/e820_64.c')
| -rw-r--r-- | arch/x86/kernel/e820_64.c | 725 |
1 files changed, 725 insertions, 0 deletions
diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c new file mode 100644 index 000000000000..0f4d5e209e9b --- /dev/null +++ b/arch/x86/kernel/e820_64.c @@ -0,0 +1,725 @@ +/* + * 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/bootsetup.h> +#include <asm/sections.h> + +struct e820map e820; + +/* + * PFN of last memory page. + */ +unsigned long end_pfn; +EXPORT_SYMBOL(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; + +extern struct resource code_resource, data_resource; + +/* 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 (LOADER_TYPE && INITRD_START && last >= INITRD_START && + addr < INITRD_START+INITRD_SIZE) { + *addrp = PAGE_ALIGN(INITRD_START + INITRD_SIZE); + 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; /* we're done */ + } + 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 = 0; + 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("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(void) +{ + 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); +#ifdef CONFIG_KEXEC + 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; + unsigned long ei_endpfn; + unsigned long 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); +} + +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("(usable)\n"); + break; + case E820_RESERVED: + printk("(reserved)\n"); + break; + case E820_ACPI: + printk("(ACPI data)\n"); + break; + case E820_NVS: + printk("(ACPI NVS)\n"); + break; + default: printk("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++) { + /* if <current_addr> > <last_addr>, swap */ + /* or, if current=<start_addr> & last=<end_addr>, swap */ + if ((change_point[i]->addr < change_point[i-1]->addr) || + ((change_point[i]->addr == change_point[i-1]->addr) && + (change_point[i]->addr == change_point[i]->pbios->addr) && + (change_point[i-1]->addr != change_point[i-1]->pbios->addr)) + ) + { + 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) + if (++new_bios_entry >= E820MAX) + break; /* no more space left for new bios entries */ + } + 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; + } + } + new_nr = new_bios_entry; /* retain count for new bios entries */ + + /* 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; +} + +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(E820_MAP, &E820_MAP_NR); + if (copy_e820_map(E820_MAP, E820_MAP_NR) < 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); +} |