/* * 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 , December 2002. * Venkatesh Pallipadi * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include 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 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 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 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 add_memory_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; } /* * 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; do { 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; add_memory_region(start, size, type); } while (biosmap++, --nr_map); return 0; } u64 __init update_memory_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; add_memory_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); } #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; } int __init page_is_reserved_early(unsigned long pagenr) { u64 start = (u64)pagenr << PAGE_SHIFT; int i; struct early_res *r; i = find_overlapped_early(start, start + PAGE_SIZE); r = &early_res[i]; return (i < MAX_EARLY_RES && r->end); } 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); #ifdef CONFIG_X86_64 reserve_bootmem_generic(final_start, final_end - final_start); #else reserve_bootmem(final_start, final_end - final_start, BOOTMEM_DEFAULT); #endif } } /* 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); update_memory_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); }