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-rw-r--r--arch/x86/kernel/e820.c1111
1 files changed, 1111 insertions, 0 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
new file mode 100644
index 00000000..62d61e99
--- /dev/null
+++ b/arch/x86/kernel/e820.c
@@ -0,0 +1,1111 @@
+/*
+ * 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/crash_dump.h>
+#include <linux/export.h>
+#include <linux/bootmem.h>
+#include <linux/pfn.h>
+#include <linux/suspend.h>
+#include <linux/acpi.h>
+#include <linux/firmware-map.h>
+#include <linux/memblock.h>
+#include <linux/sort.h>
+
+#include <asm/e820.h>
+#include <asm/proto.h>
+#include <asm/setup.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_
+ */
+struct change_member {
+ struct e820entry *pbios; /* pointer to original bios entry */
+ unsigned long long addr; /* address for this change point */
+};
+
+static int __init cpcompare(const void *a, const void *b)
+{
+ struct change_member * const *app = a, * const *bpp = b;
+ const struct change_member *ap = *app, *bp = *bpp;
+
+ /*
+ * Inputs are pointers to two elements of change_point[]. If their
+ * addresses are unequal, their difference dominates. If the addresses
+ * are equal, then consider one that represents the end of its region
+ * to be greater than one that does not.
+ */
+ if (ap->addr != bp->addr)
+ return ap->addr > bp->addr ? 1 : -1;
+
+ return (ap->addr != ap->pbios->addr) - (bp->addr != bp->pbios->addr);
+}
+
+int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
+ u32 *pnr_map)
+{
+ 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;
+ unsigned long current_type, last_type;
+ unsigned long long last_addr;
+ int chgidx;
+ 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) */
+ sort(change_point, chg_nr, sizeof *change_point, cpcompare, NULL);
+
+ /* 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 end;
+ u64 real_removed_size = 0;
+
+ if (size > (ULLONG_MAX - start))
+ size = ULLONG_MAX - start;
+
+ end = start + size;
+ printk(KERN_DEBUG "e820 remove range: %016Lx - %016Lx ",
+ (unsigned long long) start,
+ (unsigned long long) end);
+ if (checktype)
+ e820_print_type(old_type);
+ printk(KERN_CONT "\n");
+
+ for (i = 0; i < e820.nr_map; i++) {
+ struct e820entry *ei = &e820.map[i];
+ u64 final_start, final_end;
+ u64 ei_end;
+
+ if (checktype && ei->type != old_type)
+ continue;
+
+ ei_end = ei->addr + ei->size;
+ /* totally covered? */
+ if (ei->addr >= start && ei_end <= end) {
+ real_removed_size += ei->size;
+ memset(ei, 0, sizeof(struct e820entry));
+ continue;
+ }
+
+ /* new range is totally covered? */
+ if (ei->addr < start && ei_end > end) {
+ e820_add_region(end, ei_end - end, ei->type);
+ ei->size = start - ei->addr;
+ real_removed_size += size;
+ continue;
+ }
+
+ /* partially covered */
+ final_start = max(start, ei->addr);
+ final_end = min(end, ei_end);
+ if (final_start >= final_end)
+ continue;
+ real_removed_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_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)
+{
+ int entries;
+ struct e820entry *extmap;
+
+ entries = sdata->len / sizeof(struct e820entry);
+ extmap = (struct e820entry *)(sdata->data);
+ __append_e820_map(extmap, entries);
+ sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+ 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_ACPI
+/**
+ * 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)
+ acpi_nvs_register(ei->addr, ei->size);
+ }
+
+ return 0;
+}
+core_initcall(e820_mark_nvs_memory);
+#endif
+
+/*
+ * pre allocated 4k and reserved it in memblock and e820_saved
+ */
+u64 __init early_reserve_e820(u64 size, u64 align)
+{
+ u64 addr;
+
+ addr = __memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
+ if (addr) {
+ e820_update_range_saved(addr, size, E820_RAM, E820_RESERVED);
+ printk(KERN_INFO "update e820_saved for early_reserve_e820\n");
+ 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);
+}
+
+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;
+
+ if (!strcmp(p, "nopentium")) {
+#ifdef CONFIG_X86_32
+ setup_clear_cpu_cap(X86_FEATURE_PSE);
+ return 0;
+#else
+ printk(KERN_WARNING "mem=nopentium ignored! (only supported on x86_32)\n");
+ return -EINVAL;
+#endif
+ }
+
+ userdef = 1;
+ mem_size = memparse(p, &p);
+ /* don't remove all of memory when handling "mem={invalid}" param */
+ if (mem_size == 0)
+ return -EINVAL;
+ 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;
+ printk(KERN_DEBUG "reserve RAM buffer: %016llx - %016llx ",
+ start, end);
+ 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);
+}
+
+void __init memblock_x86_fill(void)
+{
+ int i;
+ u64 end;
+
+ /*
+ * EFI may have more than 128 entries
+ * We are safe to enable resizing, beause memblock_x86_fill()
+ * is rather later for x86
+ */
+ memblock_allow_resize();
+
+ for (i = 0; i < e820.nr_map; i++) {
+ struct e820entry *ei = &e820.map[i];
+
+ end = ei->addr + ei->size;
+ if (end != (resource_size_t)end)
+ continue;
+
+ if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
+ continue;
+
+ memblock_add(ei->addr, ei->size);
+ }
+
+ memblock_dump_all();
+}
+
+void __init memblock_find_dma_reserve(void)
+{
+#ifdef CONFIG_X86_64
+ u64 nr_pages = 0, nr_free_pages = 0;
+ unsigned long start_pfn, end_pfn;
+ phys_addr_t start, end;
+ int i;
+ u64 u;
+
+ /*
+ * need to find out used area below MAX_DMA_PFN
+ * need to use memblock to get free size in [0, MAX_DMA_PFN]
+ * at first, and assume boot_mem will not take below MAX_DMA_PFN
+ */
+ for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
+ start_pfn = min_t(unsigned long, start_pfn, MAX_DMA_PFN);
+ end_pfn = min_t(unsigned long, end_pfn, MAX_DMA_PFN);
+ nr_pages += end_pfn - start_pfn;
+ }
+
+ for_each_free_mem_range(u, MAX_NUMNODES, &start, &end, NULL) {
+ start_pfn = min_t(unsigned long, PFN_UP(start), MAX_DMA_PFN);
+ end_pfn = min_t(unsigned long, PFN_DOWN(end), MAX_DMA_PFN);
+ if (start_pfn < end_pfn)
+ nr_free_pages += end_pfn - start_pfn;
+ }
+
+ set_dma_reserve(nr_pages - nr_free_pages);
+#endif
+}