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/crash_dump.h>
15 #include <linux/export.h>
16 #include <linux/bootmem.h>
17 #include <linux/pfn.h>
18 #include <linux/suspend.h>
19 #include <linux/acpi.h>
20 #include <linux/firmware-map.h>
21 #include <linux/memblock.h>
24 #include <asm/proto.h>
25 #include <asm/setup.h>
28 * The e820 map is the map that gets modified e.g. with command line parameters
29 * and that is also registered with modifications in the kernel resource tree
30 * with the iomem_resource as parent.
32 * The e820_saved is directly saved after the BIOS-provided memory map is
33 * copied. It doesn't get modified afterwards. It's registered for the
34 * /sys/firmware/memmap interface.
36 * That memory map is not modified and is used as base for kexec. The kexec'd
37 * kernel should get the same memory map as the firmware provides. Then the
38 * user can e.g. boot the original kernel with mem=1G while still booting the
39 * next kernel with full memory.
42 struct e820map e820_saved
;
44 /* For PCI or other memory-mapped resources */
45 unsigned long pci_mem_start
= 0xaeedbabe;
47 EXPORT_SYMBOL(pci_mem_start
);
51 * This function checks if any part of the range <start,end> is mapped
55 e820_any_mapped(u64 start
, u64 end
, unsigned type
)
59 for (i
= 0; i
< e820
.nr_map
; i
++) {
60 struct e820entry
*ei
= &e820
.map
[i
];
62 if (type
&& ei
->type
!= type
)
64 if (ei
->addr
>= end
|| ei
->addr
+ ei
->size
<= start
)
70 EXPORT_SYMBOL_GPL(e820_any_mapped
);
73 * This function checks if the entire range <start,end> is mapped with type.
75 * Note: this function only works correct if the e820 table is sorted and
76 * not-overlapping, which is the case
78 int __init
e820_all_mapped(u64 start
, u64 end
, unsigned type
)
82 for (i
= 0; i
< e820
.nr_map
; i
++) {
83 struct e820entry
*ei
= &e820
.map
[i
];
85 if (type
&& ei
->type
!= type
)
87 /* is the region (part) in overlap with the current region ?*/
88 if (ei
->addr
>= end
|| ei
->addr
+ ei
->size
<= start
)
91 /* if the region is at the beginning of <start,end> we move
92 * start to the end of the region since it's ok until there
94 if (ei
->addr
<= start
)
95 start
= ei
->addr
+ ei
->size
;
97 * if start is now at or beyond end, we're done, full
107 * Add a memory region to the kernel e820 map.
109 static void __init
__e820_add_region(struct e820map
*e820x
, u64 start
, u64 size
,
112 int x
= e820x
->nr_map
;
114 if (x
>= ARRAY_SIZE(e820x
->map
)) {
115 printk(KERN_ERR
"Ooops! Too many entries in the memory map!\n");
119 e820x
->map
[x
].addr
= start
;
120 e820x
->map
[x
].size
= size
;
121 e820x
->map
[x
].type
= type
;
125 void __init
e820_add_region(u64 start
, u64 size
, int type
)
127 __e820_add_region(&e820
, start
, size
, type
);
130 static void __init
e820_print_type(u32 type
)
134 case E820_RESERVED_KERN
:
135 printk(KERN_CONT
"(usable)");
138 case E820_RESERVED_EFI
:
139 printk(KERN_CONT
"(reserved)");
142 printk(KERN_CONT
"(ACPI data)");
145 printk(KERN_CONT
"(ACPI NVS)");
148 printk(KERN_CONT
"(unusable)");
151 printk(KERN_CONT
"type %u", type
);
156 void __init
e820_print_map(char *who
)
160 for (i
= 0; i
< e820
.nr_map
; i
++) {
161 printk(KERN_INFO
" %s: %016Lx - %016Lx ", who
,
162 (unsigned long long) e820
.map
[i
].addr
,
164 (e820
.map
[i
].addr
+ e820
.map
[i
].size
));
165 e820_print_type(e820
.map
[i
].type
);
166 printk(KERN_CONT
"\n");
171 * Sanitize the BIOS e820 map.
173 * Some e820 responses include overlapping entries. The following
174 * replaces the original e820 map with a new one, removing overlaps,
175 * and resolving conflicting memory types in favor of highest
178 * The input parameter biosmap points to an array of 'struct
179 * e820entry' which on entry has elements in the range [0, *pnr_map)
180 * valid, and which has space for up to max_nr_map entries.
181 * On return, the resulting sanitized e820 map entries will be in
182 * overwritten in the same location, starting at biosmap.
184 * The integer pointed to by pnr_map must be valid on entry (the
185 * current number of valid entries located at biosmap) and will
186 * be updated on return, with the new number of valid entries
187 * (something no more than max_nr_map.)
189 * The return value from sanitize_e820_map() is zero if it
190 * successfully 'sanitized' the map entries passed in, and is -1
191 * if it did nothing, which can happen if either of (1) it was
192 * only passed one map entry, or (2) any of the input map entries
193 * were invalid (start + size < start, meaning that the size was
194 * so big the described memory range wrapped around through zero.)
196 * Visually we're performing the following
197 * (1,2,3,4 = memory types)...
199 * Sample memory map (w/overlaps):
200 * ____22__________________
201 * ______________________4_
202 * ____1111________________
203 * _44_____________________
204 * 11111111________________
205 * ____________________33__
206 * ___________44___________
207 * __________33333_________
208 * ______________22________
209 * ___________________2222_
210 * _________111111111______
211 * _____________________11_
212 * _________________4______
214 * Sanitized equivalent (no overlap):
215 * 1_______________________
216 * _44_____________________
217 * ___1____________________
218 * ____22__________________
219 * ______11________________
220 * _________1______________
221 * __________3_____________
222 * ___________44___________
223 * _____________33_________
224 * _______________2________
225 * ________________1_______
226 * _________________4______
227 * ___________________2____
228 * ____________________33__
229 * ______________________4_
232 int __init
sanitize_e820_map(struct e820entry
*biosmap
, int max_nr_map
,
235 struct change_member
{
236 struct e820entry
*pbios
; /* pointer to original bios entry */
237 unsigned long long addr
; /* address for this change point */
239 static struct change_member change_point_list
[2*E820_X_MAX
] __initdata
;
240 static struct change_member
*change_point
[2*E820_X_MAX
] __initdata
;
241 static struct e820entry
*overlap_list
[E820_X_MAX
] __initdata
;
242 static struct e820entry new_bios
[E820_X_MAX
] __initdata
;
243 struct change_member
*change_tmp
;
244 unsigned long current_type
, last_type
;
245 unsigned long long last_addr
;
246 int chgidx
, still_changing
;
249 int old_nr
, new_nr
, chg_nr
;
252 /* if there's only one memory region, don't bother */
257 BUG_ON(old_nr
> max_nr_map
);
259 /* bail out if we find any unreasonable addresses in bios map */
260 for (i
= 0; i
< old_nr
; i
++)
261 if (biosmap
[i
].addr
+ biosmap
[i
].size
< biosmap
[i
].addr
)
264 /* create pointers for initial change-point information (for sorting) */
265 for (i
= 0; i
< 2 * old_nr
; i
++)
266 change_point
[i
] = &change_point_list
[i
];
268 /* record all known change-points (starting and ending addresses),
269 omitting those that are for empty memory regions */
271 for (i
= 0; i
< old_nr
; i
++) {
272 if (biosmap
[i
].size
!= 0) {
273 change_point
[chgidx
]->addr
= biosmap
[i
].addr
;
274 change_point
[chgidx
++]->pbios
= &biosmap
[i
];
275 change_point
[chgidx
]->addr
= biosmap
[i
].addr
+
277 change_point
[chgidx
++]->pbios
= &biosmap
[i
];
282 /* sort change-point list by memory addresses (low -> high) */
284 while (still_changing
) {
286 for (i
= 1; i
< chg_nr
; i
++) {
287 unsigned long long curaddr
, lastaddr
;
288 unsigned long long curpbaddr
, lastpbaddr
;
290 curaddr
= change_point
[i
]->addr
;
291 lastaddr
= change_point
[i
- 1]->addr
;
292 curpbaddr
= change_point
[i
]->pbios
->addr
;
293 lastpbaddr
= change_point
[i
- 1]->pbios
->addr
;
296 * swap entries, when:
298 * curaddr > lastaddr or
299 * curaddr == lastaddr and curaddr == curpbaddr and
300 * lastaddr != lastpbaddr
302 if (curaddr
< lastaddr
||
303 (curaddr
== lastaddr
&& curaddr
== curpbaddr
&&
304 lastaddr
!= lastpbaddr
)) {
305 change_tmp
= change_point
[i
];
306 change_point
[i
] = change_point
[i
-1];
307 change_point
[i
-1] = change_tmp
;
313 /* create a new bios memory map, removing overlaps */
314 overlap_entries
= 0; /* number of entries in the overlap table */
315 new_bios_entry
= 0; /* index for creating new bios map entries */
316 last_type
= 0; /* start with undefined memory type */
317 last_addr
= 0; /* start with 0 as last starting address */
319 /* loop through change-points, determining affect on the new bios map */
320 for (chgidx
= 0; chgidx
< chg_nr
; chgidx
++) {
321 /* keep track of all overlapping bios entries */
322 if (change_point
[chgidx
]->addr
==
323 change_point
[chgidx
]->pbios
->addr
) {
325 * add map entry to overlap list (> 1 entry
326 * implies an overlap)
328 overlap_list
[overlap_entries
++] =
329 change_point
[chgidx
]->pbios
;
332 * remove entry from list (order independent,
335 for (i
= 0; i
< overlap_entries
; i
++) {
336 if (overlap_list
[i
] ==
337 change_point
[chgidx
]->pbios
)
339 overlap_list
[overlap_entries
-1];
344 * if there are overlapping entries, decide which
345 * "type" to use (larger value takes precedence --
346 * 1=usable, 2,3,4,4+=unusable)
349 for (i
= 0; i
< overlap_entries
; i
++)
350 if (overlap_list
[i
]->type
> current_type
)
351 current_type
= overlap_list
[i
]->type
;
353 * continue building up new bios map based on this
356 if (current_type
!= last_type
) {
357 if (last_type
!= 0) {
358 new_bios
[new_bios_entry
].size
=
359 change_point
[chgidx
]->addr
- last_addr
;
361 * move forward only if the new size
364 if (new_bios
[new_bios_entry
].size
!= 0)
366 * no more space left for new
369 if (++new_bios_entry
>= max_nr_map
)
372 if (current_type
!= 0) {
373 new_bios
[new_bios_entry
].addr
=
374 change_point
[chgidx
]->addr
;
375 new_bios
[new_bios_entry
].type
= current_type
;
376 last_addr
= change_point
[chgidx
]->addr
;
378 last_type
= current_type
;
381 /* retain count for new bios entries */
382 new_nr
= new_bios_entry
;
384 /* copy new bios mapping into original location */
385 memcpy(biosmap
, new_bios
, new_nr
* sizeof(struct e820entry
));
391 static int __init
__append_e820_map(struct e820entry
*biosmap
, int nr_map
)
394 u64 start
= biosmap
->addr
;
395 u64 size
= biosmap
->size
;
396 u64 end
= start
+ size
;
397 u32 type
= biosmap
->type
;
399 /* Overflow in 64 bits? Ignore the memory map. */
403 e820_add_region(start
, size
, type
);
412 * Copy the BIOS e820 map into a safe place.
414 * Sanity-check it while we're at it..
416 * If we're lucky and live on a modern system, the setup code
417 * will have given us a memory map that we can use to properly
418 * set up memory. If we aren't, we'll fake a memory map.
420 static int __init
append_e820_map(struct e820entry
*biosmap
, int nr_map
)
422 /* Only one memory region (or negative)? Ignore it */
426 return __append_e820_map(biosmap
, nr_map
);
429 static u64 __init
__e820_update_range(struct e820map
*e820x
, u64 start
,
430 u64 size
, unsigned old_type
,
435 u64 real_updated_size
= 0;
437 BUG_ON(old_type
== new_type
);
439 if (size
> (ULLONG_MAX
- start
))
440 size
= ULLONG_MAX
- start
;
443 printk(KERN_DEBUG
"e820 update range: %016Lx - %016Lx ",
444 (unsigned long long) start
,
445 (unsigned long long) end
);
446 e820_print_type(old_type
);
447 printk(KERN_CONT
" ==> ");
448 e820_print_type(new_type
);
449 printk(KERN_CONT
"\n");
451 for (i
= 0; i
< e820x
->nr_map
; i
++) {
452 struct e820entry
*ei
= &e820x
->map
[i
];
453 u64 final_start
, final_end
;
456 if (ei
->type
!= old_type
)
459 ei_end
= ei
->addr
+ ei
->size
;
460 /* totally covered by new range? */
461 if (ei
->addr
>= start
&& ei_end
<= end
) {
463 real_updated_size
+= ei
->size
;
467 /* new range is totally covered? */
468 if (ei
->addr
< start
&& ei_end
> end
) {
469 __e820_add_region(e820x
, start
, size
, new_type
);
470 __e820_add_region(e820x
, end
, ei_end
- end
, ei
->type
);
471 ei
->size
= start
- ei
->addr
;
472 real_updated_size
+= size
;
476 /* partially covered */
477 final_start
= max(start
, ei
->addr
);
478 final_end
= min(end
, ei_end
);
479 if (final_start
>= final_end
)
482 __e820_add_region(e820x
, final_start
, final_end
- final_start
,
485 real_updated_size
+= final_end
- final_start
;
488 * left range could be head or tail, so need to update
491 ei
->size
-= final_end
- final_start
;
492 if (ei
->addr
< final_start
)
494 ei
->addr
= final_end
;
496 return real_updated_size
;
499 u64 __init
e820_update_range(u64 start
, u64 size
, unsigned old_type
,
502 return __e820_update_range(&e820
, start
, size
, old_type
, new_type
);
505 static u64 __init
e820_update_range_saved(u64 start
, u64 size
,
506 unsigned old_type
, unsigned new_type
)
508 return __e820_update_range(&e820_saved
, start
, size
, old_type
,
512 /* make e820 not cover the range */
513 u64 __init
e820_remove_range(u64 start
, u64 size
, unsigned old_type
,
518 u64 real_removed_size
= 0;
520 if (size
> (ULLONG_MAX
- start
))
521 size
= ULLONG_MAX
- start
;
524 printk(KERN_DEBUG
"e820 remove range: %016Lx - %016Lx ",
525 (unsigned long long) start
,
526 (unsigned long long) end
);
528 e820_print_type(old_type
);
529 printk(KERN_CONT
"\n");
531 for (i
= 0; i
< e820
.nr_map
; i
++) {
532 struct e820entry
*ei
= &e820
.map
[i
];
533 u64 final_start
, final_end
;
536 if (checktype
&& ei
->type
!= old_type
)
539 ei_end
= ei
->addr
+ ei
->size
;
540 /* totally covered? */
541 if (ei
->addr
>= start
&& ei_end
<= end
) {
542 real_removed_size
+= ei
->size
;
543 memset(ei
, 0, sizeof(struct e820entry
));
547 /* new range is totally covered? */
548 if (ei
->addr
< start
&& ei_end
> end
) {
549 e820_add_region(end
, ei_end
- end
, ei
->type
);
550 ei
->size
= start
- ei
->addr
;
551 real_removed_size
+= size
;
555 /* partially covered */
556 final_start
= max(start
, ei
->addr
);
557 final_end
= min(end
, ei_end
);
558 if (final_start
>= final_end
)
560 real_removed_size
+= final_end
- final_start
;
563 * left range could be head or tail, so need to update
566 ei
->size
-= final_end
- final_start
;
567 if (ei
->addr
< final_start
)
569 ei
->addr
= final_end
;
571 return real_removed_size
;
574 void __init
update_e820(void)
578 nr_map
= e820
.nr_map
;
579 if (sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &nr_map
))
581 e820
.nr_map
= nr_map
;
582 printk(KERN_INFO
"modified physical RAM map:\n");
583 e820_print_map("modified");
585 static void __init
update_e820_saved(void)
589 nr_map
= e820_saved
.nr_map
;
590 if (sanitize_e820_map(e820_saved
.map
, ARRAY_SIZE(e820_saved
.map
), &nr_map
))
592 e820_saved
.nr_map
= nr_map
;
594 #define MAX_GAP_END 0x100000000ull
596 * Search for a gap in the e820 memory space from start_addr to end_addr.
598 __init
int e820_search_gap(unsigned long *gapstart
, unsigned long *gapsize
,
599 unsigned long start_addr
, unsigned long long end_addr
)
601 unsigned long long last
;
605 last
= (end_addr
&& end_addr
< MAX_GAP_END
) ? end_addr
: MAX_GAP_END
;
608 unsigned long long start
= e820
.map
[i
].addr
;
609 unsigned long long end
= start
+ e820
.map
[i
].size
;
611 if (end
< start_addr
)
615 * Since "last" is at most 4GB, we know we'll
616 * fit in 32 bits if this condition is true
619 unsigned long gap
= last
- end
;
621 if (gap
>= *gapsize
) {
634 * Search for the biggest gap in the low 32 bits of the e820
635 * memory space. We pass this space to PCI to assign MMIO resources
636 * for hotplug or unconfigured devices in.
637 * Hopefully the BIOS let enough space left.
639 __init
void e820_setup_gap(void)
641 unsigned long gapstart
, gapsize
;
644 gapstart
= 0x10000000;
646 found
= e820_search_gap(&gapstart
, &gapsize
, 0, MAX_GAP_END
);
650 gapstart
= (max_pfn
<< PAGE_SHIFT
) + 1024*1024;
652 "PCI: Warning: Cannot find a gap in the 32bit address range\n"
653 "PCI: Unassigned devices with 32bit resource registers may break!\n");
658 * e820_reserve_resources_late protect stolen RAM already
660 pci_mem_start
= gapstart
;
663 "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
664 pci_mem_start
, gapstart
, gapsize
);
668 * Because of the size limitation of struct boot_params, only first
669 * 128 E820 memory entries are passed to kernel via
670 * boot_params.e820_map, others are passed via SETUP_E820_EXT node of
671 * linked list of struct setup_data, which is parsed here.
673 void __init
parse_e820_ext(struct setup_data
*sdata
)
676 struct e820entry
*extmap
;
678 entries
= sdata
->len
/ sizeof(struct e820entry
);
679 extmap
= (struct e820entry
*)(sdata
->data
);
680 __append_e820_map(extmap
, entries
);
681 sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &e820
.nr_map
);
682 printk(KERN_INFO
"extended physical RAM map:\n");
683 e820_print_map("extended");
686 #if defined(CONFIG_X86_64) || \
687 (defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
689 * Find the ranges of physical addresses that do not correspond to
690 * e820 RAM areas and mark the corresponding pages as nosave for
691 * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
693 * This function requires the e820 map to be sorted and without any
694 * overlapping entries and assumes the first e820 area to be RAM.
696 void __init
e820_mark_nosave_regions(unsigned long limit_pfn
)
701 pfn
= PFN_DOWN(e820
.map
[0].addr
+ e820
.map
[0].size
);
702 for (i
= 1; i
< e820
.nr_map
; i
++) {
703 struct e820entry
*ei
= &e820
.map
[i
];
705 if (pfn
< PFN_UP(ei
->addr
))
706 register_nosave_region(pfn
, PFN_UP(ei
->addr
));
708 pfn
= PFN_DOWN(ei
->addr
+ ei
->size
);
709 if (ei
->type
!= E820_RAM
&& ei
->type
!= E820_RESERVED_KERN
)
710 register_nosave_region(PFN_UP(ei
->addr
), pfn
);
712 if (pfn
>= limit_pfn
)
718 #ifdef CONFIG_HIBERNATION
720 * Mark ACPI NVS memory region, so that we can save/restore it during
721 * hibernation and the subsequent resume.
723 static int __init
e820_mark_nvs_memory(void)
727 for (i
= 0; i
< e820
.nr_map
; i
++) {
728 struct e820entry
*ei
= &e820
.map
[i
];
730 if (ei
->type
== E820_NVS
)
731 suspend_nvs_register(ei
->addr
, ei
->size
);
736 core_initcall(e820_mark_nvs_memory
);
740 * pre allocated 4k and reserved it in memblock and e820_saved
742 u64 __init
early_reserve_e820(u64 startt
, u64 sizet
, u64 align
)
748 for (start
= startt
; ; start
+= size
) {
749 start
= memblock_x86_find_in_range_size(start
, &size
, align
);
750 if (start
== MEMBLOCK_ERROR
)
759 if (start
+ size
> MAXMEM
)
760 size
= MAXMEM
- start
;
763 addr
= round_down(start
+ size
- sizet
, align
);
766 memblock_x86_reserve_range(addr
, addr
+ sizet
, "new next");
767 e820_update_range_saved(addr
, sizet
, E820_RAM
, E820_RESERVED
);
768 printk(KERN_INFO
"update e820_saved for early_reserve_e820\n");
775 # ifdef CONFIG_X86_PAE
776 # define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
778 # define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
780 #else /* CONFIG_X86_32 */
781 # define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
785 * Find the highest page frame number we have available
787 unsigned long __init
e820_end_pfn(unsigned long limit_pfn
, unsigned type
)
790 unsigned long last_pfn
= 0;
791 unsigned long max_arch_pfn
= MAX_ARCH_PFN
;
793 for (i
= 0; i
< e820
.nr_map
; i
++) {
794 struct e820entry
*ei
= &e820
.map
[i
];
795 unsigned long start_pfn
;
796 unsigned long end_pfn
;
798 if (ei
->type
!= type
)
801 start_pfn
= ei
->addr
>> PAGE_SHIFT
;
802 end_pfn
= (ei
->addr
+ ei
->size
) >> PAGE_SHIFT
;
804 if (start_pfn
>= limit_pfn
)
806 if (end_pfn
> limit_pfn
) {
807 last_pfn
= limit_pfn
;
810 if (end_pfn
> last_pfn
)
814 if (last_pfn
> max_arch_pfn
)
815 last_pfn
= max_arch_pfn
;
817 printk(KERN_INFO
"last_pfn = %#lx max_arch_pfn = %#lx\n",
818 last_pfn
, max_arch_pfn
);
821 unsigned long __init
e820_end_of_ram_pfn(void)
823 return e820_end_pfn(MAX_ARCH_PFN
, E820_RAM
);
826 unsigned long __init
e820_end_of_low_ram_pfn(void)
828 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT
), E820_RAM
);
831 static void early_panic(char *msg
)
837 static int userdef __initdata
;
839 /* "mem=nopentium" disables the 4MB page tables. */
840 static int __init
parse_memopt(char *p
)
847 if (!strcmp(p
, "nopentium")) {
849 setup_clear_cpu_cap(X86_FEATURE_PSE
);
852 printk(KERN_WARNING
"mem=nopentium ignored! (only supported on x86_32)\n");
858 mem_size
= memparse(p
, &p
);
859 /* don't remove all of memory when handling "mem={invalid}" param */
862 e820_remove_range(mem_size
, ULLONG_MAX
- mem_size
, E820_RAM
, 1);
866 early_param("mem", parse_memopt
);
868 static int __init
parse_memmap_opt(char *p
)
871 u64 start_at
, mem_size
;
876 if (!strncmp(p
, "exactmap", 8)) {
877 #ifdef CONFIG_CRASH_DUMP
879 * If we are doing a crash dump, we still need to know
880 * the real mem size before original memory map is
883 saved_max_pfn
= e820_end_of_ram_pfn();
891 mem_size
= memparse(p
, &p
);
897 start_at
= memparse(p
+1, &p
);
898 e820_add_region(start_at
, mem_size
, E820_RAM
);
899 } else if (*p
== '#') {
900 start_at
= memparse(p
+1, &p
);
901 e820_add_region(start_at
, mem_size
, E820_ACPI
);
902 } else if (*p
== '$') {
903 start_at
= memparse(p
+1, &p
);
904 e820_add_region(start_at
, mem_size
, E820_RESERVED
);
906 e820_remove_range(mem_size
, ULLONG_MAX
- mem_size
, E820_RAM
, 1);
908 return *p
== '\0' ? 0 : -EINVAL
;
910 early_param("memmap", parse_memmap_opt
);
912 void __init
finish_e820_parsing(void)
915 u32 nr
= e820
.nr_map
;
917 if (sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &nr
) < 0)
918 early_panic("Invalid user supplied memory map");
921 printk(KERN_INFO
"user-defined physical RAM map:\n");
922 e820_print_map("user");
926 static inline const char *e820_type_to_string(int e820_type
)
929 case E820_RESERVED_KERN
:
930 case E820_RAM
: return "System RAM";
931 case E820_ACPI
: return "ACPI Tables";
932 case E820_NVS
: return "ACPI Non-volatile Storage";
933 case E820_UNUSABLE
: return "Unusable memory";
934 default: return "reserved";
939 * Mark e820 reserved areas as busy for the resource manager.
941 static struct resource __initdata
*e820_res
;
942 void __init
e820_reserve_resources(void)
945 struct resource
*res
;
948 res
= alloc_bootmem(sizeof(struct resource
) * e820
.nr_map
);
950 for (i
= 0; i
< e820
.nr_map
; i
++) {
951 end
= e820
.map
[i
].addr
+ e820
.map
[i
].size
- 1;
952 if (end
!= (resource_size_t
)end
) {
956 res
->name
= e820_type_to_string(e820
.map
[i
].type
);
957 res
->start
= e820
.map
[i
].addr
;
960 res
->flags
= IORESOURCE_MEM
;
963 * don't register the region that could be conflicted with
964 * pci device BAR resource and insert them later in
965 * pcibios_resource_survey()
967 if (e820
.map
[i
].type
!= E820_RESERVED
|| res
->start
< (1ULL<<20)) {
968 res
->flags
|= IORESOURCE_BUSY
;
969 insert_resource(&iomem_resource
, res
);
974 for (i
= 0; i
< e820_saved
.nr_map
; i
++) {
975 struct e820entry
*entry
= &e820_saved
.map
[i
];
976 firmware_map_add_early(entry
->addr
,
977 entry
->addr
+ entry
->size
- 1,
978 e820_type_to_string(entry
->type
));
982 /* How much should we pad RAM ending depending on where it is? */
983 static unsigned long ram_alignment(resource_size_t pos
)
985 unsigned long mb
= pos
>> 20;
987 /* To 64kB in the first megabyte */
991 /* To 1MB in the first 16MB */
995 /* To 64MB for anything above that */
999 #define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1001 void __init
e820_reserve_resources_late(void)
1004 struct resource
*res
;
1007 for (i
= 0; i
< e820
.nr_map
; i
++) {
1008 if (!res
->parent
&& res
->end
)
1009 insert_resource_expand_to_fit(&iomem_resource
, res
);
1014 * Try to bump up RAM regions to reasonable boundaries to
1017 for (i
= 0; i
< e820
.nr_map
; i
++) {
1018 struct e820entry
*entry
= &e820
.map
[i
];
1021 if (entry
->type
!= E820_RAM
)
1023 start
= entry
->addr
+ entry
->size
;
1024 end
= round_up(start
, ram_alignment(start
)) - 1;
1025 if (end
> MAX_RESOURCE_SIZE
)
1026 end
= MAX_RESOURCE_SIZE
;
1029 printk(KERN_DEBUG
"reserve RAM buffer: %016llx - %016llx ",
1031 reserve_region_with_split(&iomem_resource
, start
, end
,
1036 char *__init
default_machine_specific_memory_setup(void)
1038 char *who
= "BIOS-e820";
1041 * Try to copy the BIOS-supplied E820-map.
1043 * Otherwise fake a memory map; one section from 0k->640k,
1044 * the next section from 1mb->appropriate_mem_k
1046 new_nr
= boot_params
.e820_entries
;
1047 sanitize_e820_map(boot_params
.e820_map
,
1048 ARRAY_SIZE(boot_params
.e820_map
),
1050 boot_params
.e820_entries
= new_nr
;
1051 if (append_e820_map(boot_params
.e820_map
, boot_params
.e820_entries
)
1055 /* compare results from other methods and take the greater */
1056 if (boot_params
.alt_mem_k
1057 < boot_params
.screen_info
.ext_mem_k
) {
1058 mem_size
= boot_params
.screen_info
.ext_mem_k
;
1061 mem_size
= boot_params
.alt_mem_k
;
1066 e820_add_region(0, LOWMEMSIZE(), E820_RAM
);
1067 e820_add_region(HIGH_MEMORY
, mem_size
<< 10, E820_RAM
);
1070 /* In case someone cares... */
1074 void __init
setup_memory_map(void)
1078 who
= x86_init
.resources
.memory_setup();
1079 memcpy(&e820_saved
, &e820
, sizeof(struct e820map
));
1080 printk(KERN_INFO
"BIOS-provided physical RAM map:\n");
1081 e820_print_map(who
);
1084 void __init
memblock_x86_fill(void)
1090 * EFI may have more than 128 entries
1091 * We are safe to enable resizing, beause memblock_x86_fill()
1092 * is rather later for x86
1094 memblock_can_resize
= 1;
1096 for (i
= 0; i
< e820
.nr_map
; i
++) {
1097 struct e820entry
*ei
= &e820
.map
[i
];
1099 end
= ei
->addr
+ ei
->size
;
1100 if (end
!= (resource_size_t
)end
)
1103 if (ei
->type
!= E820_RAM
&& ei
->type
!= E820_RESERVED_KERN
)
1106 memblock_add(ei
->addr
, ei
->size
);
1110 memblock_dump_all();
1113 void __init
memblock_find_dma_reserve(void)
1115 #ifdef CONFIG_X86_64
1119 * need to find out used area below MAX_DMA_PFN
1120 * need to use memblock to get free size in [0, MAX_DMA_PFN]
1121 * at first, and assume boot_mem will not take below MAX_DMA_PFN
1123 mem_size_pfn
= memblock_x86_memory_in_range(0, MAX_DMA_PFN
<< PAGE_SHIFT
) >> PAGE_SHIFT
;
1124 free_size_pfn
= memblock_x86_free_memory_in_range(0, MAX_DMA_PFN
<< PAGE_SHIFT
) >> PAGE_SHIFT
;
1125 set_dma_reserve(mem_size_pfn
- free_size_pfn
);