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 * Find a free area with specified alignment in a specific range.
728 u64 __init
find_e820_area(u64 start
, u64 end
, u64 size
, u64 align
)
732 for (i
= 0; i
< e820
.nr_map
; i
++) {
733 struct e820entry
*ei
= &e820
.map
[i
];
735 u64 ei_start
, ei_last
;
737 if (ei
->type
!= E820_RAM
)
740 ei_last
= ei
->addr
+ ei
->size
;
742 addr
= find_early_area(ei_start
, ei_last
, start
, end
,
752 * Find next free range after *start
754 u64 __init
find_e820_area_size(u64 start
, u64
*sizep
, u64 align
)
758 for (i
= 0; i
< e820
.nr_map
; i
++) {
759 struct e820entry
*ei
= &e820
.map
[i
];
761 u64 ei_start
, ei_last
;
763 if (ei
->type
!= E820_RAM
)
766 ei_last
= ei
->addr
+ ei
->size
;
768 addr
= find_early_area_size(ei_start
, ei_last
, start
,
779 * pre allocated 4k and reserved it in e820
781 u64 __init
early_reserve_e820(u64 startt
, u64 sizet
, u64 align
)
787 for (start
= startt
; ; start
+= size
) {
788 start
= find_e820_area_size(start
, &size
, align
);
798 if (start
+ size
> MAXMEM
)
799 size
= MAXMEM
- start
;
802 addr
= round_down(start
+ size
- sizet
, align
);
805 e820_update_range(addr
, sizet
, E820_RAM
, E820_RESERVED
);
806 e820_update_range_saved(addr
, sizet
, E820_RAM
, E820_RESERVED
);
807 printk(KERN_INFO
"update e820 for early_reserve_e820\n");
815 # ifdef CONFIG_X86_PAE
816 # define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
818 # define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
820 #else /* CONFIG_X86_32 */
821 # define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
825 * Find the highest page frame number we have available
827 static unsigned long __init
e820_end_pfn(unsigned long limit_pfn
, unsigned type
)
830 unsigned long last_pfn
= 0;
831 unsigned long max_arch_pfn
= MAX_ARCH_PFN
;
833 for (i
= 0; i
< e820
.nr_map
; i
++) {
834 struct e820entry
*ei
= &e820
.map
[i
];
835 unsigned long start_pfn
;
836 unsigned long end_pfn
;
838 if (ei
->type
!= type
)
841 start_pfn
= ei
->addr
>> PAGE_SHIFT
;
842 end_pfn
= (ei
->addr
+ ei
->size
) >> PAGE_SHIFT
;
844 if (start_pfn
>= limit_pfn
)
846 if (end_pfn
> limit_pfn
) {
847 last_pfn
= limit_pfn
;
850 if (end_pfn
> last_pfn
)
854 if (last_pfn
> max_arch_pfn
)
855 last_pfn
= max_arch_pfn
;
857 printk(KERN_INFO
"last_pfn = %#lx max_arch_pfn = %#lx\n",
858 last_pfn
, max_arch_pfn
);
861 unsigned long __init
e820_end_of_ram_pfn(void)
863 return e820_end_pfn(MAX_ARCH_PFN
, E820_RAM
);
866 unsigned long __init
e820_end_of_low_ram_pfn(void)
868 return e820_end_pfn(1UL<<(32 - PAGE_SHIFT
), E820_RAM
);
871 * Finds an active region in the address range from start_pfn to last_pfn and
872 * returns its range in ei_startpfn and ei_endpfn for the e820 entry.
874 int __init
e820_find_active_region(const struct e820entry
*ei
,
875 unsigned long start_pfn
,
876 unsigned long last_pfn
,
877 unsigned long *ei_startpfn
,
878 unsigned long *ei_endpfn
)
880 u64 align
= PAGE_SIZE
;
882 *ei_startpfn
= round_up(ei
->addr
, align
) >> PAGE_SHIFT
;
883 *ei_endpfn
= round_down(ei
->addr
+ ei
->size
, align
) >> PAGE_SHIFT
;
885 /* Skip map entries smaller than a page */
886 if (*ei_startpfn
>= *ei_endpfn
)
889 /* Skip if map is outside the node */
890 if (ei
->type
!= E820_RAM
|| *ei_endpfn
<= start_pfn
||
891 *ei_startpfn
>= last_pfn
)
894 /* Check for overlaps */
895 if (*ei_startpfn
< start_pfn
)
896 *ei_startpfn
= start_pfn
;
897 if (*ei_endpfn
> last_pfn
)
898 *ei_endpfn
= last_pfn
;
903 /* Walk the e820 map and register active regions within a node */
904 void __init
e820_register_active_regions(int nid
, unsigned long start_pfn
,
905 unsigned long last_pfn
)
907 unsigned long ei_startpfn
;
908 unsigned long ei_endpfn
;
911 for (i
= 0; i
< e820
.nr_map
; i
++)
912 if (e820_find_active_region(&e820
.map
[i
],
914 &ei_startpfn
, &ei_endpfn
))
915 add_active_range(nid
, ei_startpfn
, ei_endpfn
);
919 * Find the hole size (in bytes) in the memory range.
920 * @start: starting address of the memory range to scan
921 * @end: ending address of the memory range to scan
923 u64 __init
e820_hole_size(u64 start
, u64 end
)
925 unsigned long start_pfn
= start
>> PAGE_SHIFT
;
926 unsigned long last_pfn
= end
>> PAGE_SHIFT
;
927 unsigned long ei_startpfn
, ei_endpfn
, ram
= 0;
930 for (i
= 0; i
< e820
.nr_map
; i
++) {
931 if (e820_find_active_region(&e820
.map
[i
],
933 &ei_startpfn
, &ei_endpfn
))
934 ram
+= ei_endpfn
- ei_startpfn
;
936 return end
- start
- ((u64
)ram
<< PAGE_SHIFT
);
939 static void early_panic(char *msg
)
945 static int userdef __initdata
;
947 /* "mem=nopentium" disables the 4MB page tables. */
948 static int __init
parse_memopt(char *p
)
956 if (!strcmp(p
, "nopentium")) {
957 setup_clear_cpu_cap(X86_FEATURE_PSE
);
963 mem_size
= memparse(p
, &p
);
964 e820_remove_range(mem_size
, ULLONG_MAX
- mem_size
, E820_RAM
, 1);
968 early_param("mem", parse_memopt
);
970 static int __init
parse_memmap_opt(char *p
)
973 u64 start_at
, mem_size
;
978 if (!strncmp(p
, "exactmap", 8)) {
979 #ifdef CONFIG_CRASH_DUMP
981 * If we are doing a crash dump, we still need to know
982 * the real mem size before original memory map is
985 saved_max_pfn
= e820_end_of_ram_pfn();
993 mem_size
= memparse(p
, &p
);
999 start_at
= memparse(p
+1, &p
);
1000 e820_add_region(start_at
, mem_size
, E820_RAM
);
1001 } else if (*p
== '#') {
1002 start_at
= memparse(p
+1, &p
);
1003 e820_add_region(start_at
, mem_size
, E820_ACPI
);
1004 } else if (*p
== '$') {
1005 start_at
= memparse(p
+1, &p
);
1006 e820_add_region(start_at
, mem_size
, E820_RESERVED
);
1008 e820_remove_range(mem_size
, ULLONG_MAX
- mem_size
, E820_RAM
, 1);
1010 return *p
== '\0' ? 0 : -EINVAL
;
1012 early_param("memmap", parse_memmap_opt
);
1014 void __init
finish_e820_parsing(void)
1017 u32 nr
= e820
.nr_map
;
1019 if (sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &nr
) < 0)
1020 early_panic("Invalid user supplied memory map");
1023 printk(KERN_INFO
"user-defined physical RAM map:\n");
1024 e820_print_map("user");
1028 static inline const char *e820_type_to_string(int e820_type
)
1030 switch (e820_type
) {
1031 case E820_RESERVED_KERN
:
1032 case E820_RAM
: return "System RAM";
1033 case E820_ACPI
: return "ACPI Tables";
1034 case E820_NVS
: return "ACPI Non-volatile Storage";
1035 case E820_UNUSABLE
: return "Unusable memory";
1036 default: return "reserved";
1041 * Mark e820 reserved areas as busy for the resource manager.
1043 static struct resource __initdata
*e820_res
;
1044 void __init
e820_reserve_resources(void)
1047 struct resource
*res
;
1050 res
= alloc_bootmem(sizeof(struct resource
) * e820
.nr_map
);
1052 for (i
= 0; i
< e820
.nr_map
; i
++) {
1053 end
= e820
.map
[i
].addr
+ e820
.map
[i
].size
- 1;
1054 if (end
!= (resource_size_t
)end
) {
1058 res
->name
= e820_type_to_string(e820
.map
[i
].type
);
1059 res
->start
= e820
.map
[i
].addr
;
1062 res
->flags
= IORESOURCE_MEM
;
1065 * don't register the region that could be conflicted with
1066 * pci device BAR resource and insert them later in
1067 * pcibios_resource_survey()
1069 if (e820
.map
[i
].type
!= E820_RESERVED
|| res
->start
< (1ULL<<20)) {
1070 res
->flags
|= IORESOURCE_BUSY
;
1071 insert_resource(&iomem_resource
, res
);
1076 for (i
= 0; i
< e820_saved
.nr_map
; i
++) {
1077 struct e820entry
*entry
= &e820_saved
.map
[i
];
1078 firmware_map_add_early(entry
->addr
,
1079 entry
->addr
+ entry
->size
- 1,
1080 e820_type_to_string(entry
->type
));
1084 /* How much should we pad RAM ending depending on where it is? */
1085 static unsigned long ram_alignment(resource_size_t pos
)
1087 unsigned long mb
= pos
>> 20;
1089 /* To 64kB in the first megabyte */
1093 /* To 1MB in the first 16MB */
1097 /* To 64MB for anything above that */
1098 return 64*1024*1024;
1101 #define MAX_RESOURCE_SIZE ((resource_size_t)-1)
1103 void __init
e820_reserve_resources_late(void)
1106 struct resource
*res
;
1109 for (i
= 0; i
< e820
.nr_map
; i
++) {
1110 if (!res
->parent
&& res
->end
)
1111 insert_resource_expand_to_fit(&iomem_resource
, res
);
1116 * Try to bump up RAM regions to reasonable boundaries to
1119 for (i
= 0; i
< e820
.nr_map
; i
++) {
1120 struct e820entry
*entry
= &e820
.map
[i
];
1123 if (entry
->type
!= E820_RAM
)
1125 start
= entry
->addr
+ entry
->size
;
1126 end
= round_up(start
, ram_alignment(start
)) - 1;
1127 if (end
> MAX_RESOURCE_SIZE
)
1128 end
= MAX_RESOURCE_SIZE
;
1131 printk(KERN_DEBUG
"reserve RAM buffer: %016llx - %016llx ",
1133 reserve_region_with_split(&iomem_resource
, start
, end
,
1138 char *__init
default_machine_specific_memory_setup(void)
1140 char *who
= "BIOS-e820";
1143 * Try to copy the BIOS-supplied E820-map.
1145 * Otherwise fake a memory map; one section from 0k->640k,
1146 * the next section from 1mb->appropriate_mem_k
1148 new_nr
= boot_params
.e820_entries
;
1149 sanitize_e820_map(boot_params
.e820_map
,
1150 ARRAY_SIZE(boot_params
.e820_map
),
1152 boot_params
.e820_entries
= new_nr
;
1153 if (append_e820_map(boot_params
.e820_map
, boot_params
.e820_entries
)
1157 /* compare results from other methods and take the greater */
1158 if (boot_params
.alt_mem_k
1159 < boot_params
.screen_info
.ext_mem_k
) {
1160 mem_size
= boot_params
.screen_info
.ext_mem_k
;
1163 mem_size
= boot_params
.alt_mem_k
;
1168 e820_add_region(0, LOWMEMSIZE(), E820_RAM
);
1169 e820_add_region(HIGH_MEMORY
, mem_size
<< 10, E820_RAM
);
1172 /* In case someone cares... */
1176 void __init
setup_memory_map(void)
1180 who
= x86_init
.resources
.memory_setup();
1181 memcpy(&e820_saved
, &e820
, sizeof(struct e820map
));
1182 printk(KERN_INFO
"BIOS-provided physical RAM map:\n");
1183 e820_print_map(who
);