Linux-2.6.33.2/arch/x86/kernel/e820.c
/*
* 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/pfn.h>
#include <linux/suspend.h>
#include <linux/firmware-map.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/e820.h>
#include <asm/proto.h>
#include <asm/setup.h>
#include <asm/trampoline.h>
/*
* The e820 map is the map that gets modified e.g. with command line parameters
* and that is also registered with modifications in the kernel resource tree
* with the iomem_resource as parent.
*
* The e820_saved is directly saved after the BIOS-provided memory map is
* copied. It doesn't get modified afterwards. It's registered for the
* /sys/firmware/memmap interface.
*
* That memory map is not modified and is used as base for kexec. The kexec'd
* kernel should get the same memory map as the firmware provides. Then the
* user can e.g. boot the original kernel with mem=1G while still booting the
* next kernel with full memory.
*/
struct e820map e820;
struct e820map e820_saved;
/* For PCI or other memory-mapped resources */
unsigned long pci_mem_start = 0xaeedbabe;
#ifdef CONFIG_PCI
EXPORT_SYMBOL(pci_mem_start);
#endif
/*
* This function checks if any part of the range <start,end> is mapped
* with type.
*/
int
e820_any_mapped(u64 start, u64 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(u64 start, u64 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;
}
/*
* Add a memory region to the kernel e820 map.
*/
static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
int type)
{
int x = e820x->nr_map;
if (x >= ARRAY_SIZE(e820x->map)) {
printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
return;
}
e820x->map[x].addr = start;
e820x->map[x].size = size;
e820x->map[x].type = type;
e820x->nr_map++;
}
void __init e820_add_region(u64 start, u64 size, int type)
{
__e820_add_region(&e820, start, size, type);
}
static void __init e820_print_type(u32 type)
{
switch (type) {
case E820_RAM:
case E820_RESERVED_KERN:
printk(KERN_CONT "(usable)");
break;
case E820_RESERVED:
printk(KERN_CONT "(reserved)");
break;
case E820_ACPI:
printk(KERN_CONT "(ACPI data)");
break;
case E820_NVS:
printk(KERN_CONT "(ACPI NVS)");
break;
case E820_UNUSABLE:
printk(KERN_CONT "(unusable)");
break;
default:
printk(KERN_CONT "type %u", type);
break;
}
}
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));
e820_print_type(e820.map[i].type);
printk(KERN_CONT "\n");
}
}
/*
* Sanitize the BIOS e820 map.
*
* Some e820 responses include overlapping entries. The following
* replaces the original e820 map with a new one, removing overlaps,
* and resolving conflicting memory types in favor of highest
* numbered type.
*
* The input parameter biosmap points to an array of 'struct
* e820entry' which on entry has elements in the range [0, *pnr_map)
* valid, and which has space for up to max_nr_map entries.
* On return, the resulting sanitized e820 map entries will be in
* overwritten in the same location, starting at biosmap.
*
* The integer pointed to by pnr_map must be valid on entry (the
* current number of valid entries located at biosmap) and will
* be updated on return, with the new number of valid entries
* (something no more than max_nr_map.)
*
* The return value from sanitize_e820_map() is zero if it
* successfully 'sanitized' the map entries passed in, and is -1
* if it did nothing, which can happen if either of (1) it was
* only passed one map entry, or (2) any of the input map entries
* were invalid (start + size < start, meaning that the size was
* so big the described memory range wrapped around through zero.)
*
* 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_
*/
int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
u32 *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*E820_X_MAX] __initdata;
static struct change_member *change_point[2*E820_X_MAX] __initdata;
static struct e820entry *overlap_list[E820_X_MAX] __initdata;
static struct e820entry new_bios[E820_X_MAX] __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;
/* if there's only one memory region, don't bother */
if (*pnr_map < 2)
return -1;
old_nr = *pnr_map;
BUG_ON(old_nr > max_nr_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 >= max_nr_map)
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;
}
static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
{
while (nr_map) {
u64 start = biosmap->addr;
u64 size = biosmap->size;
u64 end = start + size;
u32 type = biosmap->type;
/* Overflow in 64 bits? Ignore the memory map. */
if (start > end)
return -1;
e820_add_region(start, size, type);
biosmap++;
nr_map--;
}
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 append_e820_map(struct e820entry *biosmap, int nr_map)
{
/* Only one memory region (or negative)? Ignore it */
if (nr_map < 2)
return -1;
return __append_e820_map(biosmap, nr_map);
}
static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
u64 size, unsigned old_type,
unsigned new_type)
{
u64 end;
unsigned int i;
u64 real_updated_size = 0;
BUG_ON(old_type == new_type);
if (size > (ULLONG_MAX - start))
size = ULLONG_MAX - start;
end = start + size;
printk(KERN_DEBUG "e820 update range: %016Lx - %016Lx ",
(unsigned long long) start,
(unsigned long long) end);
e820_print_type(old_type);
printk(KERN_CONT " ==> ");
e820_print_type(new_type);
printk(KERN_CONT "\n");
for (i = 0; i < e820x->nr_map; i++) {
struct e820entry *ei = &e820x->map[i];
u64 final_start, final_end;
u64 ei_end;
if (ei->type != old_type)
continue;
ei_end = ei->addr + ei->size;
/* totally covered by new range? */
if (ei->addr >= start && ei_end <= end) {
ei->type = new_type;
real_updated_size += ei->size;
continue;
}
/* new range is totally covered? */
if (ei->addr < start && ei_end > end) {
__e820_add_region(e820x, start, size, new_type);
__e820_add_region(e820x, end, ei_end - end, ei->type);
ei->size = start - ei->addr;
real_updated_size += size;
continue;
}
/* partially covered */
final_start = max(start, ei->addr);
final_end = min(end, ei_end);
if (final_start >= final_end)
continue;
__e820_add_region(e820x, final_start, final_end - final_start,
new_type);
real_updated_size += final_end - final_start;
/*
* left range could be head or tail, so need to update
* size at first.
*/
ei->size -= final_end - final_start;
if (ei->addr < final_start)
continue;
ei->addr = final_end;
}
return real_updated_size;
}
u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
unsigned new_type)
{
return __e820_update_range(&e820, start, size, old_type, new_type);
}
static u64 __init e820_update_range_saved(u64 start, u64 size,
unsigned old_type, unsigned new_type)
{
return __e820_update_range(&e820_saved, start, size, old_type,
new_type);
}
/* make e820 not cover the range */
u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
int checktype)
{
int i;
u64 real_removed_size = 0;
if (size > (ULLONG_MAX - start))
size = ULLONG_MAX - start;
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
u64 final_start, final_end;
if (checktype && ei->type != old_type)
continue;
/* totally covered? */
if (ei->addr >= start &&
(ei->addr + ei->size) <= (start + size)) {
real_removed_size += ei->size;
memset(ei, 0, sizeof(struct e820entry));
continue;
}
/* partially covered */
final_start = max(start, ei->addr);
final_end = min(start + size, ei->addr + ei->size);
if (final_start >= final_end)
continue;
real_removed_size += final_end - final_start;
ei->size -= final_end - final_start;
if (ei->addr < final_start)
continue;
ei->addr = final_end;
}
return real_removed_size;
}
void __init update_e820(void)
{
u32 nr_map;
nr_map = e820.nr_map;
if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
return;
e820.nr_map = nr_map;
printk(KERN_INFO "modified physical RAM map:\n");
e820_print_map("modified");
}
static void __init update_e820_saved(void)
{
u32 nr_map;
nr_map = e820_saved.nr_map;
if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
return;
e820_saved.nr_map = nr_map;
}
#define MAX_GAP_END 0x100000000ull
/*
* Search for a gap in the e820 memory space from start_addr to end_addr.
*/
__init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
unsigned long start_addr, unsigned long long end_addr)
{
unsigned long long last;
int i = e820.nr_map;
int found = 0;
last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
while (--i >= 0) {
unsigned long long start = e820.map[i].addr;
unsigned long long end = start + e820.map[i].size;
if (end < start_addr)
continue;
/*
* 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;
}
return found;
}
/*
* 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;
int found;
gapstart = 0x10000000;
gapsize = 0x400000;
found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
#ifdef CONFIG_X86_64
if (!found) {
gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
printk(KERN_ERR
"PCI: Warning: Cannot find a gap in the 32bit address range\n"
"PCI: Unassigned devices with 32bit resource registers may break!\n");
}
#endif
/*
* e820_reserve_resources_late protect stolen RAM already
*/
pci_mem_start = gapstart;
printk(KERN_INFO
"Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
pci_mem_start, gapstart, gapsize);
}
/**
* Because of the size limitation of struct boot_params, only first
* 128 E820 memory entries are passed to kernel via
* boot_params.e820_map, others are passed via SETUP_E820_EXT node of
* linked list of struct setup_data, which is parsed here.
*/
void __init parse_e820_ext(struct setup_data *sdata, unsigned long pa_data)
{
u32 map_len;
int entries;
struct e820entry *extmap;
entries = sdata->len / sizeof(struct e820entry);
map_len = sdata->len + sizeof(struct setup_data);
if (map_len > PAGE_SIZE)
sdata = early_ioremap(pa_data, map_len);
extmap = (struct e820entry *)(sdata->data);
__append_e820_map(extmap, entries);
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
if (map_len > PAGE_SIZE)
early_iounmap(sdata, map_len);
printk(KERN_INFO "extended physical RAM map:\n");
e820_print_map("extended");
}
#if defined(CONFIG_X86_64) || \
(defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
/**
* Find the ranges of physical addresses that do not correspond to
* e820 RAM areas and mark the corresponding pages as nosave for
* hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
*
* 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(unsigned long limit_pfn)
{
int i;
unsigned long pfn;
pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
for (i = 1; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
if (pfn < PFN_UP(ei->addr))
register_nosave_region(pfn, PFN_UP(ei->addr));
pfn = PFN_DOWN(ei->addr + ei->size);
if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
register_nosave_region(PFN_UP(ei->addr), pfn);
if (pfn >= limit_pfn)
break;
}
}
#endif
#ifdef CONFIG_HIBERNATION
/**
* Mark ACPI NVS memory region, so that we can save/restore it during
* hibernation and the subsequent resume.
*/
static int __init e820_mark_nvs_memory(void)
{
int i;
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
if (ei->type == E820_NVS)
hibernate_nvs_register(ei->addr, ei->size);
}
return 0;
}
core_initcall(e820_mark_nvs_memory);
#endif
/*
* Early reserved memory areas.
*/
#define MAX_EARLY_RES 32
struct early_res {
u64 start, end;
char name[16];
char overlap_ok;
};
static struct early_res early_res[MAX_EARLY_RES] __initdata = {
{ 0, PAGE_SIZE, "BIOS data page", 1 }, /* BIOS data page */
#if defined(CONFIG_X86_32) && defined(CONFIG_X86_TRAMPOLINE)
/*
* But first pinch a few for the stack/trampoline stuff
* FIXME: Don't need the extra page at 4K, but need to fix
* trampoline before removing it. (see the GDT stuff)
*/
{ PAGE_SIZE, PAGE_SIZE + PAGE_SIZE, "EX TRAMPOLINE", 1 },
#endif
{}
};
static int __init find_overlapped_early(u64 start, u64 end)
{
int i;
struct early_res *r;
for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
r = &early_res[i];
if (end > r->start && start < r->end)
break;
}
return i;
}
/*
* Drop the i-th range from the early reservation map,
* by copying any higher ranges down one over it, and
* clearing what had been the last slot.
*/
static void __init drop_range(int i)
{
int j;
for (j = i + 1; j < MAX_EARLY_RES && early_res[j].end; j++)
;
memmove(&early_res[i], &early_res[i + 1],
(j - 1 - i) * sizeof(struct early_res));
early_res[j - 1].end = 0;
}
/*
* Split any existing ranges that:
* 1) are marked 'overlap_ok', and
* 2) overlap with the stated range [start, end)
* into whatever portion (if any) of the existing range is entirely
* below or entirely above the stated range. Drop the portion
* of the existing range that overlaps with the stated range,
* which will allow the caller of this routine to then add that
* stated range without conflicting with any existing range.
*/
static void __init drop_overlaps_that_are_ok(u64 start, u64 end)
{
int i;
struct early_res *r;
u64 lower_start, lower_end;
u64 upper_start, upper_end;
char name[16];
for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
r = &early_res[i];
/* Continue past non-overlapping ranges */
if (end <= r->start || start >= r->end)
continue;
/*
* Leave non-ok overlaps as is; let caller
* panic "Overlapping early reservations"
* when it hits this overlap.
*/
if (!r->overlap_ok)
return;
/*
* We have an ok overlap. We will drop it from the early
* reservation map, and add back in any non-overlapping
* portions (lower or upper) as separate, overlap_ok,
* non-overlapping ranges.
*/
/* 1. Note any non-overlapping (lower or upper) ranges. */
strncpy(name, r->name, sizeof(name) - 1);
lower_start = lower_end = 0;
upper_start = upper_end = 0;
if (r->start < start) {
lower_start = r->start;
lower_end = start;
}
if (r->end > end) {
upper_start = end;
upper_end = r->end;
}
/* 2. Drop the original ok overlapping range */
drop_range(i);
i--; /* resume for-loop on copied down entry */
/* 3. Add back in any non-overlapping ranges. */
if (lower_end)
reserve_early_overlap_ok(lower_start, lower_end, name);
if (upper_end)
reserve_early_overlap_ok(upper_start, upper_end, name);
}
}
static void __init __reserve_early(u64 start, u64 end, char *name,
int overlap_ok)
{
int i;
struct early_res *r;
i = find_overlapped_early(start, end);
if (i >= MAX_EARLY_RES)
panic("Too many early reservations");
r = &early_res[i];
if (r->end)
panic("Overlapping early reservations "
"%llx-%llx %s to %llx-%llx %s\n",
start, end - 1, name?name:"", r->start,
r->end - 1, r->name);
r->start = start;
r->end = end;
r->overlap_ok = overlap_ok;
if (name)
strncpy(r->name, name, sizeof(r->name) - 1);
}
/*
* A few early reservtations come here.
*
* The 'overlap_ok' in the name of this routine does -not- mean it
* is ok for these reservations to overlap an earlier reservation.
* Rather it means that it is ok for subsequent reservations to
* overlap this one.
*
* Use this entry point to reserve early ranges when you are doing
* so out of "Paranoia", reserving perhaps more memory than you need,
* just in case, and don't mind a subsequent overlapping reservation
* that is known to be needed.
*
* The drop_overlaps_that_are_ok() call here isn't really needed.
* It would be needed if we had two colliding 'overlap_ok'
* reservations, so that the second such would not panic on the
* overlap with the first. We don't have any such as of this
* writing, but might as well tolerate such if it happens in
* the future.
*/
void __init reserve_early_overlap_ok(u64 start, u64 end, char *name)
{
drop_overlaps_that_are_ok(start, end);
__reserve_early(start, end, name, 1);
}
/*
* Most early reservations come here.
*
* We first have drop_overlaps_that_are_ok() drop any pre-existing
* 'overlap_ok' ranges, so that we can then reserve this memory
* range without risk of panic'ing on an overlapping overlap_ok
* early reservation.
*/
void __init reserve_early(u64 start, u64 end, char *name)
{
if (start >= end)
return;
drop_overlaps_that_are_ok(start, end);
__reserve_early(start, end, name, 0);
}
void __init free_early(u64 start, u64 end)
{
struct early_res *r;
int i;
i = find_overlapped_early(start, end);
r = &early_res[i];
if (i >= MAX_EARLY_RES || r->end != end || r->start != start)
panic("free_early on not reserved area: %llx-%llx!",
start, end - 1);
drop_range(i);
}
void __init early_res_to_bootmem(u64 start, u64 end)
{
int i, count;
u64 final_start, final_end;
count = 0;
for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++)
count++;
printk(KERN_INFO "(%d early reservations) ==> bootmem [%010llx - %010llx]\n",
count, start, end);
for (i = 0; i < count; i++) {
struct early_res *r = &early_res[i];
printk(KERN_INFO " #%d [%010llx - %010llx] %16s", i,
r->start, r->end, r->name);
final_start = max(start, r->start);
final_end = min(end, r->end);
if (final_start >= final_end) {
printk(KERN_CONT "\n");
continue;
}
printk(KERN_CONT " ==> [%010llx - %010llx]\n",
final_start, final_end);
reserve_bootmem_generic(final_start, final_end - final_start,
BOOTMEM_DEFAULT);
}
}
/* Check for already reserved areas */
static inline int __init bad_addr(u64 *addrp, u64 size, u64 align)
{
int i;
u64 addr = *addrp;
int changed = 0;
struct early_res *r;
again:
i = find_overlapped_early(addr, addr + size);
r = &early_res[i];
if (i < MAX_EARLY_RES && r->end) {
*addrp = addr = round_up(r->end, align);
changed = 1;
goto again;
}
return changed;
}
/* Check for already reserved areas */
static inline int __init bad_addr_size(u64 *addrp, u64 *sizep, u64 align)
{
int i;
u64 addr = *addrp, last;
u64 size = *sizep;
int changed = 0;
again:
last = addr + size;
for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
struct early_res *r = &early_res[i];
if (last > r->start && addr < r->start) {
size = r->start - addr;
changed = 1;
goto again;
}
if (last > r->end && addr < r->end) {
addr = round_up(r->end, align);
size = last - addr;
changed = 1;
goto again;
}
if (last <= r->end && addr >= r->start) {
(*sizep)++;
return 0;
}
}
if (changed) {
*addrp = addr;
*sizep = size;
}
return changed;
}
/*
* Find a free area with specified alignment in a specific range.
*/
u64 __init find_e820_area(u64 start, u64 end, u64 size, u64 align)
{
int i;
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
u64 addr, last;
u64 ei_last;
if (ei->type != E820_RAM)
continue;
addr = round_up(ei->addr, align);
ei_last = ei->addr + ei->size;
if (addr < start)
addr = round_up(start, align);
if (addr >= ei_last)
continue;
while (bad_addr(&addr, size, align) && addr+size <= ei_last)
;
last = addr + size;
if (last > ei_last)
continue;
if (last > end)
continue;
return addr;
}
return -1ULL;
}
/*
* Find next free range after *start
*/
u64 __init find_e820_area_size(u64 start, u64 *sizep, u64 align)
{
int i;
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
u64 addr, last;
u64 ei_last;
if (ei->type != E820_RAM)
continue;
addr = round_up(ei->addr, align);
ei_last = ei->addr + ei->size;
if (addr < start)
addr = round_up(start, align);
if (addr >= ei_last)
continue;
*sizep = ei_last - addr;
while (bad_addr_size(&addr, sizep, align) &&
addr + *sizep <= ei_last)
;
last = addr + *sizep;
if (last > ei_last)
continue;
return addr;
}
return -1ULL;
}
/*
* pre allocated 4k and reserved it in e820
*/
u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
{
u64 size = 0;
u64 addr;
u64 start;
for (start = startt; ; start += size) {
start = find_e820_area_size(start, &size, align);
if (!(start + 1))
return 0;
if (size >= sizet)
break;
}
#ifdef CONFIG_X86_32
if (start >= MAXMEM)
return 0;
if (start + size > MAXMEM)
size = MAXMEM - start;
#endif
addr = round_down(start + size - sizet, align);
if (addr < start)
return 0;
e820_update_range(addr, sizet, E820_RAM, E820_RESERVED);
e820_update_range_saved(addr, sizet, E820_RAM, E820_RESERVED);
printk(KERN_INFO "update e820 for early_reserve_e820\n");
update_e820();
update_e820_saved();
return addr;
}
#ifdef CONFIG_X86_32
# ifdef CONFIG_X86_PAE
# define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
# else
# define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
# endif
#else /* CONFIG_X86_32 */
# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
#endif
/*
* Find the highest page frame number we have available
*/
static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
{
int i;
unsigned long last_pfn = 0;
unsigned long max_arch_pfn = MAX_ARCH_PFN;
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
unsigned long start_pfn;
unsigned long end_pfn;
if (ei->type != type)
continue;
start_pfn = ei->addr >> PAGE_SHIFT;
end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
if (start_pfn >= limit_pfn)
continue;
if (end_pfn > limit_pfn) {
last_pfn = limit_pfn;
break;
}
if (end_pfn > last_pfn)
last_pfn = end_pfn;
}
if (last_pfn > max_arch_pfn)
last_pfn = max_arch_pfn;
printk(KERN_INFO "last_pfn = %#lx max_arch_pfn = %#lx\n",
last_pfn, max_arch_pfn);
return last_pfn;
}
unsigned long __init e820_end_of_ram_pfn(void)
{
return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
}
unsigned long __init e820_end_of_low_ram_pfn(void)
{
return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
}
/*
* Finds an active region in the address range from start_pfn to last_pfn and
* returns its range in ei_startpfn and ei_endpfn for the e820 entry.
*/
int __init e820_find_active_region(const struct e820entry *ei,
unsigned long start_pfn,
unsigned long last_pfn,
unsigned long *ei_startpfn,
unsigned long *ei_endpfn)
{
u64 align = PAGE_SIZE;
*ei_startpfn = round_up(ei->addr, align) >> PAGE_SHIFT;
*ei_endpfn = round_down(ei->addr + ei->size, align) >> PAGE_SHIFT;
/* Skip map entries smaller than a page */
if (*ei_startpfn >= *ei_endpfn)
return 0;
/* Skip if map is outside the node */
if (ei->type != E820_RAM || *ei_endpfn <= start_pfn ||
*ei_startpfn >= last_pfn)
return 0;
/* Check for overlaps */
if (*ei_startpfn < start_pfn)
*ei_startpfn = start_pfn;
if (*ei_endpfn > last_pfn)
*ei_endpfn = last_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 last_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, last_pfn,
&ei_startpfn, &ei_endpfn))
add_active_range(nid, ei_startpfn, ei_endpfn);
}
/*
* 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
*/
u64 __init e820_hole_size(u64 start, u64 end)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long last_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, last_pfn,
&ei_startpfn, &ei_endpfn))
ram += ei_endpfn - ei_startpfn;
}
return end - start - ((u64)ram << PAGE_SHIFT);
}
static void early_panic(char *msg)
{
early_printk(msg);
panic(msg);
}
static int userdef __initdata;
/* "mem=nopentium" disables the 4MB page tables. */
static int __init parse_memopt(char *p)
{
u64 mem_size;
if (!p)
return -EINVAL;
#ifdef CONFIG_X86_32
if (!strcmp(p, "nopentium")) {
setup_clear_cpu_cap(X86_FEATURE_PSE);
return 0;
}
#endif
userdef = 1;
mem_size = memparse(p, &p);
e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
return 0;
}
early_param("mem", parse_memopt);
static int __init parse_memmap_opt(char *p)
{
char *oldp;
u64 start_at, mem_size;
if (!p)
return -EINVAL;
if (!strncmp(p, "exactmap", 8)) {
#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.
*/
saved_max_pfn = e820_end_of_ram_pfn();
#endif
e820.nr_map = 0;
userdef = 1;
return 0;
}
oldp = p;
mem_size = memparse(p, &p);
if (p == oldp)
return -EINVAL;
userdef = 1;
if (*p == '@') {
start_at = memparse(p+1, &p);
e820_add_region(start_at, mem_size, E820_RAM);
} else if (*p == '#') {
start_at = memparse(p+1, &p);
e820_add_region(start_at, mem_size, E820_ACPI);
} else if (*p == '$') {
start_at = memparse(p+1, &p);
e820_add_region(start_at, mem_size, E820_RESERVED);
} else
e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
return *p == '\0' ? 0 : -EINVAL;
}
early_param("memmap", parse_memmap_opt);
void __init finish_e820_parsing(void)
{
if (userdef) {
u32 nr = e820.nr_map;
if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
early_panic("Invalid user supplied memory map");
e820.nr_map = nr;
printk(KERN_INFO "user-defined physical RAM map:\n");
e820_print_map("user");
}
}
static inline const char *e820_type_to_string(int e820_type)
{
switch (e820_type) {
case E820_RESERVED_KERN:
case E820_RAM: return "System RAM";
case E820_ACPI: return "ACPI Tables";
case E820_NVS: return "ACPI Non-volatile Storage";
case E820_UNUSABLE: return "Unusable memory";
default: return "reserved";
}
}
/*
* Mark e820 reserved areas as busy for the resource manager.
*/
static struct resource __initdata *e820_res;
void __init e820_reserve_resources(void)
{
int i;
struct resource *res;
u64 end;
res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
e820_res = res;
for (i = 0; i < e820.nr_map; i++) {
end = e820.map[i].addr + e820.map[i].size - 1;
if (end != (resource_size_t)end) {
res++;
continue;
}
res->name = e820_type_to_string(e820.map[i].type);
res->start = e820.map[i].addr;
res->end = end;
res->flags = IORESOURCE_MEM;
/*
* don't register the region that could be conflicted with
* pci device BAR resource and insert them later in
* pcibios_resource_survey()
*/
if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
res->flags |= IORESOURCE_BUSY;
insert_resource(&iomem_resource, res);
}
res++;
}
for (i = 0; i < e820_saved.nr_map; i++) {
struct e820entry *entry = &e820_saved.map[i];
firmware_map_add_early(entry->addr,
entry->addr + entry->size - 1,
e820_type_to_string(entry->type));
}
}
/* How much should we pad RAM ending depending on where it is? */
static unsigned long ram_alignment(resource_size_t pos)
{
unsigned long mb = pos >> 20;
/* To 64kB in the first megabyte */
if (!mb)
return 64*1024;
/* To 1MB in the first 16MB */
if (mb < 16)
return 1024*1024;
/* To 64MB for anything above that */
return 64*1024*1024;
}
#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
void __init e820_reserve_resources_late(void)
{
int i;
struct resource *res;
res = e820_res;
for (i = 0; i < e820.nr_map; i++) {
if (!res->parent && res->end)
insert_resource_expand_to_fit(&iomem_resource, res);
res++;
}
/*
* Try to bump up RAM regions to reasonable boundaries to
* avoid stolen RAM:
*/
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *entry = &e820.map[i];
u64 start, end;
if (entry->type != E820_RAM)
continue;
start = entry->addr + entry->size;
end = round_up(start, ram_alignment(start)) - 1;
if (end > MAX_RESOURCE_SIZE)
end = MAX_RESOURCE_SIZE;
if (start >= end)
continue;
reserve_region_with_split(&iomem_resource, start, end,
"RAM buffer");
}
}
char *__init default_machine_specific_memory_setup(void)
{
char *who = "BIOS-e820";
u32 new_nr;
/*
* 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
*/
new_nr = boot_params.e820_entries;
sanitize_e820_map(boot_params.e820_map,
ARRAY_SIZE(boot_params.e820_map),
&new_nr);
boot_params.e820_entries = new_nr;
if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
< 0) {
u64 mem_size;
/* compare results from other methods and take the greater */
if (boot_params.alt_mem_k
< boot_params.screen_info.ext_mem_k) {
mem_size = boot_params.screen_info.ext_mem_k;
who = "BIOS-88";
} else {
mem_size = boot_params.alt_mem_k;
who = "BIOS-e801";
}
e820.nr_map = 0;
e820_add_region(0, LOWMEMSIZE(), E820_RAM);
e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
}
/* In case someone cares... */
return who;
}
void __init setup_memory_map(void)
{
char *who;
who = x86_init.resources.memory_setup();
memcpy(&e820_saved, &e820, sizeof(struct e820map));
printk(KERN_INFO "BIOS-provided physical RAM map:\n");
e820_print_map(who);
}