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linux_old1/arch/x86/kernel/e820_64.c

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/*
* 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>
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, bss_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 (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(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);
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);
}
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;
}
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;
}
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