2 * Handle the memory map.
3 * The functions here do the job until bootmem takes over.
5 * Getting sanitize_e820_map() in sync with i386 version by applying change:
6 * - Provisions for empty E820 memory regions (reported by certain BIOSes).
7 * Alex Achenbach <xela@slit.de>, December 2002.
8 * Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/init.h>
14 #include <linux/bootmem.h>
15 #include <linux/pfn.h>
16 #include <linux/suspend.h>
17 #include <linux/firmware-map.h>
20 #include <asm/early_res.h>
21 #include <asm/proto.h>
22 #include <asm/setup.h>
25 * The e820 map is the map that gets modified e.g. with command line parameters
26 * and that is also registered with modifications in the kernel resource tree
27 * with the iomem_resource as parent.
29 * The e820_saved is directly saved after the BIOS-provided memory map is
30 * copied. It doesn't get modified afterwards. It's registered for the
31 * /sys/firmware/memmap interface.
33 * That memory map is not modified and is used as base for kexec. The kexec'd
34 * kernel should get the same memory map as the firmware provides. Then the
35 * user can e.g. boot the original kernel with mem=1G while still booting the
36 * next kernel with full memory.
39 struct e820map e820_saved;
41 /* For PCI or other memory-mapped resources */
42 unsigned long pci_mem_start = 0xaeedbabe;
44 EXPORT_SYMBOL(pci_mem_start);
48 * This function checks if any part of the range <start,end> is mapped
52 e820_any_mapped(u64 start, u64 end, unsigned type)
56 for (i = 0; i < e820.nr_map; i++) {
57 struct e820entry *ei = &e820.map[i];
59 if (type && ei->type != type)
61 if (ei->addr >= end || ei->addr + ei->size <= start)
67 EXPORT_SYMBOL_GPL(e820_any_mapped);
70 * This function checks if the entire range <start,end> is mapped with type.
72 * Note: this function only works correct if the e820 table is sorted and
73 * not-overlapping, which is the case
75 int __init e820_all_mapped(u64 start, u64 end, unsigned type)
79 for (i = 0; i < e820.nr_map; i++) {
80 struct e820entry *ei = &e820.map[i];
82 if (type && ei->type != type)
84 /* is the region (part) in overlap with the current region ?*/
85 if (ei->addr >= end || ei->addr + ei->size <= start)
88 /* if the region is at the beginning of <start,end> we move
89 * start to the end of the region since it's ok until there
91 if (ei->addr <= start)
92 start = ei->addr + ei->size;
94 * if start is now at or beyond end, we're done, full
104 * Add a memory region to the kernel e820 map.
106 static void __init __e820_add_region(struct e820map *e820x, u64 start, u64 size,
109 int x = e820x->nr_map;
111 if (x >= ARRAY_SIZE(e820x->map)) {
112 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
116 e820x->map[x].addr = start;
117 e820x->map[x].size = size;
118 e820x->map[x].type = type;
122 void __init e820_add_region(u64 start, u64 size, int type)
124 __e820_add_region(&e820, start, size, type);
127 static void __init e820_print_type(u32 type)
131 case E820_RESERVED_KERN:
132 printk(KERN_CONT "(usable)");
135 printk(KERN_CONT "(reserved)");
138 printk(KERN_CONT "(ACPI data)");
141 printk(KERN_CONT "(ACPI NVS)");
144 printk(KERN_CONT "(unusable)");
147 printk(KERN_CONT "type %u", type);
152 void __init e820_print_map(char *who)
156 for (i = 0; i < e820.nr_map; i++) {
157 printk(KERN_INFO " %s: %016Lx - %016Lx ", who,
158 (unsigned long long) e820.map[i].addr,
160 (e820.map[i].addr + e820.map[i].size));
161 e820_print_type(e820.map[i].type);
162 printk(KERN_CONT "\n");
167 * Sanitize the BIOS e820 map.
169 * Some e820 responses include overlapping entries. The following
170 * replaces the original e820 map with a new one, removing overlaps,
171 * and resolving conflicting memory types in favor of highest
174 * The input parameter biosmap points to an array of 'struct
175 * e820entry' which on entry has elements in the range [0, *pnr_map)
176 * valid, and which has space for up to max_nr_map entries.
177 * On return, the resulting sanitized e820 map entries will be in
178 * overwritten in the same location, starting at biosmap.
180 * The integer pointed to by pnr_map must be valid on entry (the
181 * current number of valid entries located at biosmap) and will
182 * be updated on return, with the new number of valid entries
183 * (something no more than max_nr_map.)
185 * The return value from sanitize_e820_map() is zero if it
186 * successfully 'sanitized' the map entries passed in, and is -1
187 * if it did nothing, which can happen if either of (1) it was
188 * only passed one map entry, or (2) any of the input map entries
189 * were invalid (start + size < start, meaning that the size was
190 * so big the described memory range wrapped around through zero.)
192 * Visually we're performing the following
193 * (1,2,3,4 = memory types)...
195 * Sample memory map (w/overlaps):
196 * ____22__________________
197 * ______________________4_
198 * ____1111________________
199 * _44_____________________
200 * 11111111________________
201 * ____________________33__
202 * ___________44___________
203 * __________33333_________
204 * ______________22________
205 * ___________________2222_
206 * _________111111111______
207 * _____________________11_
208 * _________________4______
210 * Sanitized equivalent (no overlap):
211 * 1_______________________
212 * _44_____________________
213 * ___1____________________
214 * ____22__________________
215 * ______11________________
216 * _________1______________
217 * __________3_____________
218 * ___________44___________
219 * _____________33_________
220 * _______________2________
221 * ________________1_______
222 * _________________4______
223 * ___________________2____
224 * ____________________33__
225 * ______________________4_
228 int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
231 struct change_member {
232 struct e820entry *pbios; /* pointer to original bios entry */
233 unsigned long long addr; /* address for this change point */
235 static struct change_member change_point_list[2*E820_X_MAX] __initdata;
236 static struct change_member *change_point[2*E820_X_MAX] __initdata;
237 static struct e820entry *overlap_list[E820_X_MAX] __initdata;
238 static struct e820entry new_bios[E820_X_MAX] __initdata;
239 struct change_member *change_tmp;
240 unsigned long current_type, last_type;
241 unsigned long long last_addr;
242 int chgidx, still_changing;
245 int old_nr, new_nr, chg_nr;
248 /* if there's only one memory region, don't bother */
253 BUG_ON(old_nr > max_nr_map);
255 /* bail out if we find any unreasonable addresses in bios map */
256 for (i = 0; i < old_nr; i++)
257 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr)
260 /* create pointers for initial change-point information (for sorting) */
261 for (i = 0; i < 2 * old_nr; i++)
262 change_point[i] = &change_point_list[i];
264 /* record all known change-points (starting and ending addresses),
265 omitting those that are for empty memory regions */
267 for (i = 0; i < old_nr; i++) {
268 if (biosmap[i].size != 0) {
269 change_point[chgidx]->addr = biosmap[i].addr;
270 change_point[chgidx++]->pbios = &biosmap[i];
271 change_point[chgidx]->addr = biosmap[i].addr +
273 change_point[chgidx++]->pbios = &biosmap[i];
278 /* sort change-point list by memory addresses (low -> high) */
280 while (still_changing) {
282 for (i = 1; i < chg_nr; i++) {
283 unsigned long long curaddr, lastaddr;
284 unsigned long long curpbaddr, lastpbaddr;
286 curaddr = change_point[i]->addr;
287 lastaddr = change_point[i - 1]->addr;
288 curpbaddr = change_point[i]->pbios->addr;
289 lastpbaddr = change_point[i - 1]->pbios->addr;
292 * swap entries, when:
294 * curaddr > lastaddr or
295 * curaddr == lastaddr and curaddr == curpbaddr and
296 * lastaddr != lastpbaddr
298 if (curaddr < lastaddr ||
299 (curaddr == lastaddr && curaddr == curpbaddr &&
300 lastaddr != lastpbaddr)) {
301 change_tmp = change_point[i];
302 change_point[i] = change_point[i-1];
303 change_point[i-1] = change_tmp;
309 /* create a new bios memory map, removing overlaps */
310 overlap_entries = 0; /* number of entries in the overlap table */
311 new_bios_entry = 0; /* index for creating new bios map entries */
312 last_type = 0; /* start with undefined memory type */
313 last_addr = 0; /* start with 0 as last starting address */
315 /* loop through change-points, determining affect on the new bios map */
316 for (chgidx = 0; chgidx < chg_nr; chgidx++) {
317 /* keep track of all overlapping bios entries */
318 if (change_point[chgidx]->addr ==
319 change_point[chgidx]->pbios->addr) {
321 * add map entry to overlap list (> 1 entry
322 * implies an overlap)
324 overlap_list[overlap_entries++] =
325 change_point[chgidx]->pbios;
328 * remove entry from list (order independent,
331 for (i = 0; i < overlap_entries; i++) {
332 if (overlap_list[i] ==
333 change_point[chgidx]->pbios)
335 overlap_list[overlap_entries-1];
340 * if there are overlapping entries, decide which
341 * "type" to use (larger value takes precedence --
342 * 1=usable, 2,3,4,4+=unusable)
345 for (i = 0; i < overlap_entries; i++)
346 if (overlap_list[i]->type > current_type)
347 current_type = overlap_list[i]->type;
349 * continue building up new bios map based on this
352 if (current_type != last_type) {
353 if (last_type != 0) {
354 new_bios[new_bios_entry].size =
355 change_point[chgidx]->addr - last_addr;
357 * move forward only if the new size
360 if (new_bios[new_bios_entry].size != 0)
362 * no more space left for new
365 if (++new_bios_entry >= max_nr_map)
368 if (current_type != 0) {
369 new_bios[new_bios_entry].addr =
370 change_point[chgidx]->addr;
371 new_bios[new_bios_entry].type = current_type;
372 last_addr = change_point[chgidx]->addr;
374 last_type = current_type;
377 /* retain count for new bios entries */
378 new_nr = new_bios_entry;
380 /* copy new bios mapping into original location */
381 memcpy(biosmap, new_bios, new_nr * sizeof(struct e820entry));
387 static int __init __append_e820_map(struct e820entry *biosmap, int nr_map)
390 u64 start = biosmap->addr;
391 u64 size = biosmap->size;
392 u64 end = start + size;
393 u32 type = biosmap->type;
395 /* Overflow in 64 bits? Ignore the memory map. */
399 e820_add_region(start, size, type);
408 * Copy the BIOS e820 map into a safe place.
410 * Sanity-check it while we're at it..
412 * If we're lucky and live on a modern system, the setup code
413 * will have given us a memory map that we can use to properly
414 * set up memory. If we aren't, we'll fake a memory map.
416 static int __init append_e820_map(struct e820entry *biosmap, int nr_map)
418 /* Only one memory region (or negative)? Ignore it */
422 return __append_e820_map(biosmap, nr_map);
425 static u64 __init __e820_update_range(struct e820map *e820x, u64 start,
426 u64 size, unsigned old_type,
431 u64 real_updated_size = 0;
433 BUG_ON(old_type == new_type);
435 if (size > (ULLONG_MAX - start))
436 size = ULLONG_MAX - start;
439 printk(KERN_DEBUG "e820 update range: %016Lx - %016Lx ",
440 (unsigned long long) start,
441 (unsigned long long) end);
442 e820_print_type(old_type);
443 printk(KERN_CONT " ==> ");
444 e820_print_type(new_type);
445 printk(KERN_CONT "\n");
447 for (i = 0; i < e820x->nr_map; i++) {
448 struct e820entry *ei = &e820x->map[i];
449 u64 final_start, final_end;
452 if (ei->type != old_type)
455 ei_end = ei->addr + ei->size;
456 /* totally covered by new range? */
457 if (ei->addr >= start && ei_end <= end) {
459 real_updated_size += ei->size;
463 /* new range is totally covered? */
464 if (ei->addr < start && ei_end > end) {
465 __e820_add_region(e820x, start, size, new_type);
466 __e820_add_region(e820x, end, ei_end - end, ei->type);
467 ei->size = start - ei->addr;
468 real_updated_size += size;
472 /* partially covered */
473 final_start = max(start, ei->addr);
474 final_end = min(end, ei_end);
475 if (final_start >= final_end)
478 __e820_add_region(e820x, final_start, final_end - final_start,
481 real_updated_size += final_end - final_start;
484 * left range could be head or tail, so need to update
487 ei->size -= final_end - final_start;
488 if (ei->addr < final_start)
490 ei->addr = final_end;
492 return real_updated_size;
495 u64 __init e820_update_range(u64 start, u64 size, unsigned old_type,
498 return __e820_update_range(&e820, start, size, old_type, new_type);
501 static u64 __init e820_update_range_saved(u64 start, u64 size,
502 unsigned old_type, unsigned new_type)
504 return __e820_update_range(&e820_saved, start, size, old_type,
508 /* make e820 not cover the range */
509 u64 __init e820_remove_range(u64 start, u64 size, unsigned old_type,
514 u64 real_removed_size = 0;
516 if (size > (ULLONG_MAX - start))
517 size = ULLONG_MAX - start;
520 printk(KERN_DEBUG "e820 remove range: %016Lx - %016Lx ",
521 (unsigned long long) start,
522 (unsigned long long) end);
523 e820_print_type(old_type);
524 printk(KERN_CONT "\n");
526 for (i = 0; i < e820.nr_map; i++) {
527 struct e820entry *ei = &e820.map[i];
528 u64 final_start, final_end;
530 if (checktype && ei->type != old_type)
532 /* totally covered? */
533 if (ei->addr >= start &&
534 (ei->addr + ei->size) <= (start + size)) {
535 real_removed_size += ei->size;
536 memset(ei, 0, sizeof(struct e820entry));
539 /* partially covered */
540 final_start = max(start, ei->addr);
541 final_end = min(start + size, ei->addr + ei->size);
542 if (final_start >= final_end)
544 real_removed_size += final_end - final_start;
546 ei->size -= final_end - final_start;
547 if (ei->addr < final_start)
549 ei->addr = final_end;
551 return real_removed_size;
554 void __init update_e820(void)
558 nr_map = e820.nr_map;
559 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr_map))
561 e820.nr_map = nr_map;
562 printk(KERN_INFO "modified physical RAM map:\n");
563 e820_print_map("modified");
565 static void __init update_e820_saved(void)
569 nr_map = e820_saved.nr_map;
570 if (sanitize_e820_map(e820_saved.map, ARRAY_SIZE(e820_saved.map), &nr_map))
572 e820_saved.nr_map = nr_map;
574 #define MAX_GAP_END 0x100000000ull
576 * Search for a gap in the e820 memory space from start_addr to end_addr.
578 __init int e820_search_gap(unsigned long *gapstart, unsigned long *gapsize,
579 unsigned long start_addr, unsigned long long end_addr)
581 unsigned long long last;
585 last = (end_addr && end_addr < MAX_GAP_END) ? end_addr : MAX_GAP_END;
588 unsigned long long start = e820.map[i].addr;
589 unsigned long long end = start + e820.map[i].size;
591 if (end < start_addr)
595 * Since "last" is at most 4GB, we know we'll
596 * fit in 32 bits if this condition is true
599 unsigned long gap = last - end;
601 if (gap >= *gapsize) {
614 * Search for the biggest gap in the low 32 bits of the e820
615 * memory space. We pass this space to PCI to assign MMIO resources
616 * for hotplug or unconfigured devices in.
617 * Hopefully the BIOS let enough space left.
619 __init void e820_setup_gap(void)
621 unsigned long gapstart, gapsize;
624 gapstart = 0x10000000;
626 found = e820_search_gap(&gapstart, &gapsize, 0, MAX_GAP_END);
630 gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
632 "PCI: Warning: Cannot find a gap in the 32bit address range\n"
633 "PCI: Unassigned devices with 32bit resource registers may break!\n");
638 * e820_reserve_resources_late protect stolen RAM already
640 pci_mem_start = gapstart;
643 "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
644 pci_mem_start, gapstart, gapsize);
648 * Because of the size limitation of struct boot_params, only first
649 * 128 E820 memory entries are passed to kernel via
650 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
651 * linked list of struct setup_data, which is parsed here.
653 void __init parse_e820_ext(struct setup_data *sdata, unsigned long pa_data)
657 struct e820entry *extmap;
659 entries = sdata->len / sizeof(struct e820entry);
660 map_len = sdata->len + sizeof(struct setup_data);
661 if (map_len > PAGE_SIZE)
662 sdata = early_ioremap(pa_data, map_len);
663 extmap = (struct e820entry *)(sdata->data);
664 __append_e820_map(extmap, entries);
665 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
666 if (map_len > PAGE_SIZE)
667 early_iounmap(sdata, map_len);
668 printk(KERN_INFO "extended physical RAM map:\n");
669 e820_print_map("extended");
672 #if defined(CONFIG_X86_64) || \
673 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
675 * Find the ranges of physical addresses that do not correspond to
676 * e820 RAM areas and mark the corresponding pages as nosave for
677 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
679 * This function requires the e820 map to be sorted and without any
680 * overlapping entries and assumes the first e820 area to be RAM.
682 void __init e820_mark_nosave_regions(unsigned long limit_pfn)
687 pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
688 for (i = 1; i < e820.nr_map; i++) {
689 struct e820entry *ei = &e820.map[i];
691 if (pfn < PFN_UP(ei->addr))
692 register_nosave_region(pfn, PFN_UP(ei->addr));
694 pfn = PFN_DOWN(ei->addr + ei->size);
695 if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
696 register_nosave_region(PFN_UP(ei->addr), pfn);
698 if (pfn >= limit_pfn)
704 #ifdef CONFIG_HIBERNATION
706 * Mark ACPI NVS memory region, so that we can save/restore it during
707 * hibernation and the subsequent resume.
709 static int __init e820_mark_nvs_memory(void)
713 for (i = 0; i < e820.nr_map; i++) {
714 struct e820entry *ei = &e820.map[i];
716 if (ei->type == E820_NVS)
717 hibernate_nvs_register(ei->addr, ei->size);
722 core_initcall(e820_mark_nvs_memory);
726 * pre allocated 4k and reserved it in e820
728 u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
734 for (start = startt; ; start += size) {
735 start = find_e820_area_size(start, &size, align);
745 if (start + size > MAXMEM)
746 size = MAXMEM - start;
749 addr = round_down(start + size - sizet, align);
752 e820_update_range(addr, sizet, E820_RAM, E820_RESERVED);
753 e820_update_range_saved(addr, sizet, E820_RAM, E820_RESERVED);
754 printk(KERN_INFO "update e820 for early_reserve_e820\n");
762 # ifdef CONFIG_X86_PAE
763 # define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
765 # define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
767 #else /* CONFIG_X86_32 */
768 # define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
772 * Find the highest page frame number we have available
774 static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
777 unsigned long last_pfn = 0;
778 unsigned long max_arch_pfn = MAX_ARCH_PFN;
780 for (i = 0; i < e820.nr_map; i++) {
781 struct e820entry *ei = &e820.map[i];
782 unsigned long start_pfn;
783 unsigned long end_pfn;
785 if (ei->type != type)
788 start_pfn = ei->addr >> PAGE_SHIFT;
789 end_pfn = (ei->addr + ei->size) >> PAGE_SHIFT;
791 if (start_pfn >= limit_pfn)
793 if (end_pfn > limit_pfn) {
794 last_pfn = limit_pfn;
797 if (end_pfn > last_pfn)
801 if (last_pfn > max_arch_pfn)
802 last_pfn = max_arch_pfn;
804 printk(KERN_INFO "last_pfn = %#lx max_arch_pfn = %#lx\n",
805 last_pfn, max_arch_pfn);
808 unsigned long __init e820_end_of_ram_pfn(void)
810 return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
813 unsigned long __init e820_end_of_low_ram_pfn(void)
815 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
818 * Finds an active region in the address range from start_pfn to last_pfn and
819 * returns its range in ei_startpfn and ei_endpfn for the e820 entry.
821 int __init e820_find_active_region(const struct e820entry *ei,
822 unsigned long start_pfn,
823 unsigned long last_pfn,
824 unsigned long *ei_startpfn,
825 unsigned long *ei_endpfn)
827 u64 align = PAGE_SIZE;
829 *ei_startpfn = round_up(ei->addr, align) >> PAGE_SHIFT;
830 *ei_endpfn = round_down(ei->addr + ei->size, align) >> PAGE_SHIFT;
832 /* Skip map entries smaller than a page */
833 if (*ei_startpfn >= *ei_endpfn)
836 /* Skip if map is outside the node */
837 if (ei->type != E820_RAM || *ei_endpfn <= start_pfn ||
838 *ei_startpfn >= last_pfn)
841 /* Check for overlaps */
842 if (*ei_startpfn < start_pfn)
843 *ei_startpfn = start_pfn;
844 if (*ei_endpfn > last_pfn)
845 *ei_endpfn = last_pfn;
850 /* Walk the e820 map and register active regions within a node */
851 void __init e820_register_active_regions(int nid, unsigned long start_pfn,
852 unsigned long last_pfn)
854 unsigned long ei_startpfn;
855 unsigned long ei_endpfn;
858 for (i = 0; i < e820.nr_map; i++)
859 if (e820_find_active_region(&e820.map[i],
861 &ei_startpfn, &ei_endpfn))
862 add_active_range(nid, ei_startpfn, ei_endpfn);
866 * Find the hole size (in bytes) in the memory range.
867 * @start: starting address of the memory range to scan
868 * @end: ending address of the memory range to scan
870 u64 __init e820_hole_size(u64 start, u64 end)
872 unsigned long start_pfn = start >> PAGE_SHIFT;
873 unsigned long last_pfn = end >> PAGE_SHIFT;
874 unsigned long ei_startpfn, ei_endpfn, ram = 0;
877 for (i = 0; i < e820.nr_map; i++) {
878 if (e820_find_active_region(&e820.map[i],
880 &ei_startpfn, &ei_endpfn))
881 ram += ei_endpfn - ei_startpfn;
883 return end - start - ((u64)ram << PAGE_SHIFT);
886 static void early_panic(char *msg)
892 static int userdef __initdata;
894 /* "mem=nopentium" disables the 4MB page tables. */
895 static int __init parse_memopt(char *p)
903 if (!strcmp(p, "nopentium")) {
904 setup_clear_cpu_cap(X86_FEATURE_PSE);
910 mem_size = memparse(p, &p);
911 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
915 early_param("mem", parse_memopt);
917 static int __init parse_memmap_opt(char *p)
920 u64 start_at, mem_size;
925 if (!strncmp(p, "exactmap", 8)) {
926 #ifdef CONFIG_CRASH_DUMP
928 * If we are doing a crash dump, we still need to know
929 * the real mem size before original memory map is
932 saved_max_pfn = e820_end_of_ram_pfn();
940 mem_size = memparse(p, &p);
946 start_at = memparse(p+1, &p);
947 e820_add_region(start_at, mem_size, E820_RAM);
948 } else if (*p == '#') {
949 start_at = memparse(p+1, &p);
950 e820_add_region(start_at, mem_size, E820_ACPI);
951 } else if (*p == '$') {
952 start_at = memparse(p+1, &p);
953 e820_add_region(start_at, mem_size, E820_RESERVED);
955 e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
957 return *p == '\0' ? 0 : -EINVAL;
959 early_param("memmap", parse_memmap_opt);
961 void __init finish_e820_parsing(void)
964 u32 nr = e820.nr_map;
966 if (sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &nr) < 0)
967 early_panic("Invalid user supplied memory map");
970 printk(KERN_INFO "user-defined physical RAM map:\n");
971 e820_print_map("user");
975 static inline const char *e820_type_to_string(int e820_type)
978 case E820_RESERVED_KERN:
979 case E820_RAM: return "System RAM";
980 case E820_ACPI: return "ACPI Tables";
981 case E820_NVS: return "ACPI Non-volatile Storage";
982 case E820_UNUSABLE: return "Unusable memory";
983 default: return "reserved";
988 * Mark e820 reserved areas as busy for the resource manager.
990 static struct resource __initdata *e820_res;
991 void __init e820_reserve_resources(void)
994 struct resource *res;
997 res = alloc_bootmem(sizeof(struct resource) * e820.nr_map);
999 for (i = 0; i < e820.nr_map; i++) {
1000 end = e820.map[i].addr + e820.map[i].size - 1;
1001 if (end != (resource_size_t)end) {
1005 res->name = e820_type_to_string(e820.map[i].type);
1006 res->start = e820.map[i].addr;
1009 res->flags = IORESOURCE_MEM;
1012 * don't register the region that could be conflicted with
1013 * pci device BAR resource and insert them later in
1014 * pcibios_resource_survey()
1016 if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
1017 res->flags |= IORESOURCE_BUSY;
1018 insert_resource(&iomem_resource, res);
1023 for (i = 0; i < e820_saved.nr_map; i++) {
1024 struct e820entry *entry = &e820_saved.map[i];
1025 firmware_map_add_early(entry->addr,
1026 entry->addr + entry->size - 1,
1027 e820_type_to_string(entry->type));
1031 /* How much should we pad RAM ending depending on where it is? */
1032 static unsigned long ram_alignment(resource_size_t pos)
1034 unsigned long mb = pos >> 20;
1036 /* To 64kB in the first megabyte */
1040 /* To 1MB in the first 16MB */
1044 /* To 64MB for anything above that */
1045 return 64*1024*1024;
1048 #define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1050 void __init e820_reserve_resources_late(void)
1053 struct resource *res;
1056 for (i = 0; i < e820.nr_map; i++) {
1057 if (!res->parent && res->end)
1058 insert_resource_expand_to_fit(&iomem_resource, res);
1063 * Try to bump up RAM regions to reasonable boundaries to
1066 for (i = 0; i < e820.nr_map; i++) {
1067 struct e820entry *entry = &e820.map[i];
1070 if (entry->type != E820_RAM)
1072 start = entry->addr + entry->size;
1073 end = round_up(start, ram_alignment(start)) - 1;
1074 if (end > MAX_RESOURCE_SIZE)
1075 end = MAX_RESOURCE_SIZE;
1078 printk(KERN_DEBUG "reserve RAM buffer: %016llx - %016llx ",
1080 reserve_region_with_split(&iomem_resource, start, end,
1085 char *__init default_machine_specific_memory_setup(void)
1087 char *who = "BIOS-e820";
1090 * Try to copy the BIOS-supplied E820-map.
1092 * Otherwise fake a memory map; one section from 0k->640k,
1093 * the next section from 1mb->appropriate_mem_k
1095 new_nr = boot_params.e820_entries;
1096 sanitize_e820_map(boot_params.e820_map,
1097 ARRAY_SIZE(boot_params.e820_map),
1099 boot_params.e820_entries = new_nr;
1100 if (append_e820_map(boot_params.e820_map, boot_params.e820_entries)
1104 /* compare results from other methods and take the greater */
1105 if (boot_params.alt_mem_k
1106 < boot_params.screen_info.ext_mem_k) {
1107 mem_size = boot_params.screen_info.ext_mem_k;
1110 mem_size = boot_params.alt_mem_k;
1115 e820_add_region(0, LOWMEMSIZE(), E820_RAM);
1116 e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
1119 /* In case someone cares... */
1123 void __init setup_memory_map(void)
1127 who = x86_init.resources.memory_setup();
1128 memcpy(&e820_saved, &e820, sizeof(struct e820map));
1129 printk(KERN_INFO "BIOS-provided physical RAM map:\n");
1130 e820_print_map(who);