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-rw-r--r--arch/x86/kernel/e820.c1105
1 files changed, 1105 insertions, 0 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
new file mode 100644
index 0000000..7b613d2
--- /dev/null
+++ b/arch/x86/kernel/e820.c
@@ -0,0 +1,1105 @@
+/*
+ * 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 <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/e820.h>
+#include <asm/proto.h>
+#include <asm/setup.h>
+#include <asm/trampoline.h>
+
+struct e820map e820;
+
+/* 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.
+ */
+void __init e820_add_region(u64 start, u64 size, int type)
+{
+ int x = e820.nr_map;
+
+ if (x == ARRAY_SIZE(e820.map)) {
+ 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++;
+}
+
+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,
+ * 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,
+ int *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 __copy_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.
+ */
+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;
+
+ return __copy_e820_map(biosmap, nr_map);
+}
+
+u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
+ unsigned new_type)
+{
+ int i;
+ u64 real_updated_size = 0;
+
+ BUG_ON(old_type == new_type);
+
+ for (i = 0; i < e820.nr_map; i++) {
+ struct e820entry *ei = &e820.map[i];
+ u64 final_start, final_end;
+ if (ei->type != old_type)
+ continue;
+ /* totally covered? */
+ if (ei->addr >= start &&
+ (ei->addr + ei->size) <= (start + size)) {
+ ei->type = new_type;
+ real_updated_size += ei->size;
+ continue;
+ }
+ /* partially covered */
+ final_start = max(start, ei->addr);
+ final_end = min(start + size, ei->addr + ei->size);
+ if (final_start >= final_end)
+ continue;
+ e820_add_region(final_start, final_end - final_start,
+ new_type);
+ real_updated_size += final_end - final_start;
+ }
+ return real_updated_size;
+}
+
+void __init update_e820(void)
+{
+ int 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");
+}
+
+/*
+ * 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 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;
+ }
+
+#ifdef CONFIG_X86_64
+ 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");
+ }
+#endif
+
+ /*
+ * 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);
+}
+
+/**
+ * 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);
+ __copy_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)
+ register_nosave_region(PFN_UP(ei->addr), pfn);
+
+ if (pfn >= limit_pfn)
+ break;
+ }
+}
+#endif
+
+/*
+ * Early reserved memory areas.
+ */
+#define MAX_EARLY_RES 20
+
+struct early_res {
+ u64 start, end;
+ char name[16];
+};
+static struct early_res early_res[MAX_EARLY_RES] __initdata = {
+ { 0, PAGE_SIZE, "BIOS data page" }, /* BIOS data page */
+#if defined(CONFIG_X86_64) && defined(CONFIG_X86_TRAMPOLINE)
+ { TRAMPOLINE_BASE, TRAMPOLINE_BASE + 2 * PAGE_SIZE, "TRAMPOLINE" },
+#endif
+#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
+ /*
+ * 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" },
+ /*
+ * Has to be in very low memory so we can execute
+ * real-mode AP code.
+ */
+ { TRAMPOLINE_BASE, TRAMPOLINE_BASE + PAGE_SIZE, "TRAMPOLINE" },
+#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;
+}
+
+void __init reserve_early(u64 start, u64 end, char *name)
+{
+ 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;
+ if (name)
+ strncpy(r->name, name, sizeof(r->name) - 1);
+}
+
+void __init free_early(u64 start, u64 end)
+{
+ struct early_res *r;
+ int i, j;
+
+ 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);
+
+ 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;
+}
+
+void __init early_res_to_bootmem(u64 start, u64 end)
+{
+ int i;
+ u64 final_start, final_end;
+ for (i = 0; i < MAX_EARLY_RES && early_res[i].end; i++) {
+ struct early_res *r = &early_res[i];
+ final_start = max(start, r->start);
+ final_end = min(end, r->end);
+ if (final_start >= final_end)
+ continue;
+ printk(KERN_INFO " early res: %d [%llx-%llx] %s\n", i,
+ final_start, final_end - 1, r->name);
+ 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 -1UL;
+
+}
+
+/*
+ * 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;
+
+ start = startt;
+ while (size < sizet)
+ start = find_e820_area_size(start, &size, align);
+
+ if (size < sizet)
+ return 0;
+
+ addr = round_down(start + size - sizet, align);
+ e820_update_range(addr, sizet, E820_RAM, E820_RESERVED);
+ printk(KERN_INFO "update e820 for early_reserve_e820\n");
+ update_e820();
+
+ 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
+
+/*
+ * Last pfn which the user wants to use.
+ */
+unsigned long __initdata end_user_pfn = MAX_ARCH_PFN;
+
+/*
+ * Find the highest page frame number we have available
+ */
+unsigned long __init e820_end_of_ram(void)
+{
+ unsigned long last_pfn;
+ unsigned long max_arch_pfn = MAX_ARCH_PFN;
+
+ last_pfn = find_max_pfn_with_active_regions();
+
+ if (last_pfn > max_arch_pfn)
+ last_pfn = max_arch_pfn;
+ if (last_pfn > end_user_pfn)
+ last_pfn = end_user_pfn;
+
+ printk(KERN_INFO "last_pfn = %lu max_arch_pfn = %lu\n",
+ last_pfn, max_arch_pfn);
+ return last_pfn;
+}
+
+/*
+ * 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;
+
+ /* 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 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);
+}
+
+/* "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
+
+ mem_size = memparse(p, &p);
+ end_user_pfn = mem_size>>PAGE_SHIFT;
+ return 0;
+}
+early_param("mem", parse_memopt);
+
+static int userdef __initdata;
+
+static int __init parse_memmap_opt(char *p)
+{
+ char *oldp;
+ u64 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
+ 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 {
+ 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) {
+ int 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");
+ }
+}
+
+/*
+ * Mark e820 reserved areas as busy for the resource manager.
+ */
+void __init e820_reserve_resources(void)
+{
+ int i;
+ struct resource *res;
+
+ res = alloc_bootmem_low(sizeof(struct resource) * e820.nr_map);
+ for (i = 0; i < e820.nr_map; i++) {
+ 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;
+#ifndef CONFIG_RESOURCES_64BIT
+ if (res->end > 0x100000000ULL) {
+ res++;
+ continue;
+ }
+#endif
+ res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+ insert_resource(&iomem_resource, res);
+ res++;
+ }
+}
+
+char *__init default_machine_specific_memory_setup(void)
+{
+ char *who = "BIOS-e820";
+ int 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 (copy_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;
+}
+
+char *__init __attribute__((weak)) machine_specific_memory_setup(void)
+{
+ return default_machine_specific_memory_setup();
+}
+
+/* Overridden in paravirt.c if CONFIG_PARAVIRT */
+char * __init __attribute__((weak)) memory_setup(void)
+{
+ return machine_specific_memory_setup();
+}
+
+void __init setup_memory_map(void)
+{
+ printk(KERN_INFO "BIOS-provided physical RAM map:\n");
+ e820_print_map(memory_setup());
+}
+
+#ifdef CONFIG_X86_64
+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;
+}
+#endif