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/ioport.h>
16 #include <linux/string.h>
17 #include <linux/kexec.h>
18 #include <linux/module.h>
20 #include <linux/suspend.h>
21 #include <linux/pfn.h>
23 #include <asm/pgtable.h>
26 #include <asm/proto.h>
27 #include <asm/setup.h>
28 #include <asm/sections.h>
29 #include <asm/kdebug.h>
34 * PFN of last memory page.
36 unsigned long end_pfn
;
39 * end_pfn only includes RAM, while max_pfn_mapped includes all e820 entries.
40 * The direct mapping extends to max_pfn_mapped, so that we can directly access
41 * apertures, ACPI and other tables without having to play with fixmaps.
43 unsigned long max_pfn_mapped
;
46 * Last pfn which the user wants to use.
48 static unsigned long __initdata end_user_pfn
= MAXMEM
>>PAGE_SHIFT
;
51 * Early reserved memory areas.
53 #define MAX_EARLY_RES 20
56 unsigned long start
, end
;
59 static struct early_res early_res
[MAX_EARLY_RES
] __initdata
= {
60 { 0, PAGE_SIZE
, "BIOS data page" }, /* BIOS data page */
62 { SMP_TRAMPOLINE_BASE
, SMP_TRAMPOLINE_BASE
+ 2*PAGE_SIZE
, "SMP_TRAMPOLINE" },
67 void __init
reserve_early(unsigned long start
, unsigned long end
, char *name
)
71 for (i
= 0; i
< MAX_EARLY_RES
&& early_res
[i
].end
; i
++) {
73 if (end
> r
->start
&& start
< r
->end
)
74 panic("Overlapping early reservations %lx-%lx %s to %lx-%lx %s\n",
75 start
, end
- 1, name
?name
:"", r
->start
, r
->end
- 1, r
->name
);
77 if (i
>= MAX_EARLY_RES
)
78 panic("Too many early reservations");
83 strncpy(r
->name
, name
, sizeof(r
->name
) - 1);
86 void __init
early_res_to_bootmem(void)
89 for (i
= 0; i
< MAX_EARLY_RES
&& early_res
[i
].end
; i
++) {
90 struct early_res
*r
= &early_res
[i
];
91 printk(KERN_INFO
"early res: %d [%lx-%lx] %s\n", i
,
92 r
->start
, r
->end
- 1, r
->name
);
93 reserve_bootmem_generic(r
->start
, r
->end
- r
->start
);
97 /* Check for already reserved areas */
99 bad_addr(unsigned long *addrp
, unsigned long size
, unsigned long align
)
102 unsigned long addr
= *addrp
, last
;
106 for (i
= 0; i
< MAX_EARLY_RES
&& early_res
[i
].end
; i
++) {
107 struct early_res
*r
= &early_res
[i
];
108 if (last
>= r
->start
&& addr
< r
->end
) {
109 *addrp
= addr
= round_up(r
->end
, align
);
117 /* Check for already reserved areas */
119 bad_addr_size(unsigned long *addrp
, unsigned long *sizep
, unsigned long align
)
122 unsigned long addr
= *addrp
, last
;
123 unsigned long size
= *sizep
;
127 for (i
= 0; i
< MAX_EARLY_RES
&& early_res
[i
].end
; i
++) {
128 struct early_res
*r
= &early_res
[i
];
129 if (last
> r
->start
&& addr
< r
->start
) {
130 size
= r
->start
- addr
;
134 if (last
> r
->end
&& addr
< r
->end
) {
135 addr
= round_up(r
->end
, align
);
140 if (last
<= r
->end
&& addr
>= r
->start
) {
152 * This function checks if any part of the range <start,end> is mapped
156 e820_any_mapped(unsigned long start
, unsigned long end
, unsigned type
)
160 for (i
= 0; i
< e820
.nr_map
; i
++) {
161 struct e820entry
*ei
= &e820
.map
[i
];
163 if (type
&& ei
->type
!= type
)
165 if (ei
->addr
>= end
|| ei
->addr
+ ei
->size
<= start
)
171 EXPORT_SYMBOL_GPL(e820_any_mapped
);
174 * This function checks if the entire range <start,end> is mapped with type.
176 * Note: this function only works correct if the e820 table is sorted and
177 * not-overlapping, which is the case
179 int __init
e820_all_mapped(unsigned long start
, unsigned long end
,
184 for (i
= 0; i
< e820
.nr_map
; i
++) {
185 struct e820entry
*ei
= &e820
.map
[i
];
187 if (type
&& ei
->type
!= type
)
189 /* is the region (part) in overlap with the current region ?*/
190 if (ei
->addr
>= end
|| ei
->addr
+ ei
->size
<= start
)
193 /* if the region is at the beginning of <start,end> we move
194 * start to the end of the region since it's ok until there
196 if (ei
->addr
<= start
)
197 start
= ei
->addr
+ ei
->size
;
199 * if start is now at or beyond end, we're done, full
209 * Find a free area with specified alignment in a specific range.
211 unsigned long __init
find_e820_area(unsigned long start
, unsigned long end
,
212 unsigned long size
, unsigned long align
)
216 for (i
= 0; i
< e820
.nr_map
; i
++) {
217 struct e820entry
*ei
= &e820
.map
[i
];
218 unsigned long addr
, last
;
219 unsigned long ei_last
;
221 if (ei
->type
!= E820_RAM
)
223 addr
= round_up(ei
->addr
, align
);
224 ei_last
= ei
->addr
+ ei
->size
;
226 addr
= round_up(start
, align
);
229 while (bad_addr(&addr
, size
, align
) && addr
+size
<= ei_last
)
242 * Find next free range after *start
244 unsigned long __init
find_e820_area_size(unsigned long start
,
245 unsigned long *sizep
,
250 for (i
= 0; i
< e820
.nr_map
; i
++) {
251 struct e820entry
*ei
= &e820
.map
[i
];
252 unsigned long addr
, last
;
253 unsigned long ei_last
;
255 if (ei
->type
!= E820_RAM
)
257 addr
= round_up(ei
->addr
, align
);
258 ei_last
= ei
->addr
+ ei
->size
;
260 addr
= round_up(start
, align
);
263 *sizep
= ei_last
- addr
;
264 while (bad_addr_size(&addr
, sizep
, align
) &&
265 addr
+ *sizep
<= ei_last
)
267 last
= addr
+ *sizep
;
276 * Find the highest page frame number we have available
278 unsigned long __init
e820_end_of_ram(void)
280 unsigned long end_pfn
;
282 end_pfn
= find_max_pfn_with_active_regions();
284 if (end_pfn
> max_pfn_mapped
)
285 max_pfn_mapped
= end_pfn
;
286 if (max_pfn_mapped
> MAXMEM
>>PAGE_SHIFT
)
287 max_pfn_mapped
= MAXMEM
>>PAGE_SHIFT
;
288 if (end_pfn
> end_user_pfn
)
289 end_pfn
= end_user_pfn
;
290 if (end_pfn
> max_pfn_mapped
)
291 end_pfn
= max_pfn_mapped
;
293 printk(KERN_INFO
"max_pfn_mapped = %lu\n", max_pfn_mapped
);
298 * Mark e820 reserved areas as busy for the resource manager.
300 void __init
e820_reserve_resources(void)
303 struct resource
*res
;
305 res
= alloc_bootmem_low(sizeof(struct resource
) * e820
.nr_map
);
306 for (i
= 0; i
< e820
.nr_map
; i
++) {
307 switch (e820
.map
[i
].type
) {
308 case E820_RAM
: res
->name
= "System RAM"; break;
309 case E820_ACPI
: res
->name
= "ACPI Tables"; break;
310 case E820_NVS
: res
->name
= "ACPI Non-volatile Storage"; break;
311 default: res
->name
= "reserved";
313 res
->start
= e820
.map
[i
].addr
;
314 res
->end
= res
->start
+ e820
.map
[i
].size
- 1;
315 res
->flags
= IORESOURCE_MEM
| IORESOURCE_BUSY
;
316 insert_resource(&iomem_resource
, res
);
322 * Find the ranges of physical addresses that do not correspond to
323 * e820 RAM areas and mark the corresponding pages as nosave for software
324 * suspend and suspend to RAM.
326 * This function requires the e820 map to be sorted and without any
327 * overlapping entries and assumes the first e820 area to be RAM.
329 void __init
e820_mark_nosave_regions(void)
334 paddr
= round_down(e820
.map
[0].addr
+ e820
.map
[0].size
, PAGE_SIZE
);
335 for (i
= 1; i
< e820
.nr_map
; i
++) {
336 struct e820entry
*ei
= &e820
.map
[i
];
338 if (paddr
< ei
->addr
)
339 register_nosave_region(PFN_DOWN(paddr
),
342 paddr
= round_down(ei
->addr
+ ei
->size
, PAGE_SIZE
);
343 if (ei
->type
!= E820_RAM
)
344 register_nosave_region(PFN_UP(ei
->addr
),
347 if (paddr
>= (end_pfn
<< PAGE_SHIFT
))
353 * Finds an active region in the address range from start_pfn to end_pfn and
354 * returns its range in ei_startpfn and ei_endpfn for the e820 entry.
356 static int __init
e820_find_active_region(const struct e820entry
*ei
,
357 unsigned long start_pfn
,
358 unsigned long end_pfn
,
359 unsigned long *ei_startpfn
,
360 unsigned long *ei_endpfn
)
362 *ei_startpfn
= round_up(ei
->addr
, PAGE_SIZE
) >> PAGE_SHIFT
;
363 *ei_endpfn
= round_down(ei
->addr
+ ei
->size
, PAGE_SIZE
) >> PAGE_SHIFT
;
365 /* Skip map entries smaller than a page */
366 if (*ei_startpfn
>= *ei_endpfn
)
369 /* Check if max_pfn_mapped should be updated */
370 if (ei
->type
!= E820_RAM
&& *ei_endpfn
> max_pfn_mapped
)
371 max_pfn_mapped
= *ei_endpfn
;
373 /* Skip if map is outside the node */
374 if (ei
->type
!= E820_RAM
|| *ei_endpfn
<= start_pfn
||
375 *ei_startpfn
>= end_pfn
)
378 /* Check for overlaps */
379 if (*ei_startpfn
< start_pfn
)
380 *ei_startpfn
= start_pfn
;
381 if (*ei_endpfn
> end_pfn
)
382 *ei_endpfn
= end_pfn
;
384 /* Obey end_user_pfn to save on memmap */
385 if (*ei_startpfn
>= end_user_pfn
)
387 if (*ei_endpfn
> end_user_pfn
)
388 *ei_endpfn
= end_user_pfn
;
393 /* Walk the e820 map and register active regions within a node */
395 e820_register_active_regions(int nid
, unsigned long start_pfn
,
396 unsigned long end_pfn
)
398 unsigned long ei_startpfn
;
399 unsigned long ei_endpfn
;
402 for (i
= 0; i
< e820
.nr_map
; i
++)
403 if (e820_find_active_region(&e820
.map
[i
],
405 &ei_startpfn
, &ei_endpfn
))
406 add_active_range(nid
, ei_startpfn
, ei_endpfn
);
410 * Add a memory region to the kernel e820 map.
412 void __init
add_memory_region(unsigned long start
, unsigned long size
, int type
)
417 printk(KERN_ERR
"Ooops! Too many entries in the memory map!\n");
421 e820
.map
[x
].addr
= start
;
422 e820
.map
[x
].size
= size
;
423 e820
.map
[x
].type
= type
;
428 * Find the hole size (in bytes) in the memory range.
429 * @start: starting address of the memory range to scan
430 * @end: ending address of the memory range to scan
432 unsigned long __init
e820_hole_size(unsigned long start
, unsigned long end
)
434 unsigned long start_pfn
= start
>> PAGE_SHIFT
;
435 unsigned long end_pfn
= end
>> PAGE_SHIFT
;
436 unsigned long ei_startpfn
, ei_endpfn
, ram
= 0;
439 for (i
= 0; i
< e820
.nr_map
; i
++) {
440 if (e820_find_active_region(&e820
.map
[i
],
442 &ei_startpfn
, &ei_endpfn
))
443 ram
+= ei_endpfn
- ei_startpfn
;
445 return end
- start
- (ram
<< PAGE_SHIFT
);
448 static void __init
e820_print_map(char *who
)
452 for (i
= 0; i
< e820
.nr_map
; i
++) {
453 printk(KERN_INFO
" %s: %016Lx - %016Lx ", who
,
454 (unsigned long long) e820
.map
[i
].addr
,
456 (e820
.map
[i
].addr
+ e820
.map
[i
].size
));
457 switch (e820
.map
[i
].type
) {
459 printk(KERN_CONT
"(usable)\n");
462 printk(KERN_CONT
"(reserved)\n");
465 printk(KERN_CONT
"(ACPI data)\n");
468 printk(KERN_CONT
"(ACPI NVS)\n");
471 printk(KERN_CONT
"type %u\n", e820
.map
[i
].type
);
478 * Sanitize the BIOS e820 map.
480 * Some e820 responses include overlapping entries. The following
481 * replaces the original e820 map with a new one, removing overlaps.
484 static int __init
sanitize_e820_map(struct e820entry
*biosmap
, char *pnr_map
)
486 struct change_member
{
487 struct e820entry
*pbios
; /* pointer to original bios entry */
488 unsigned long long addr
; /* address for this change point */
490 static struct change_member change_point_list
[2*E820MAX
] __initdata
;
491 static struct change_member
*change_point
[2*E820MAX
] __initdata
;
492 static struct e820entry
*overlap_list
[E820MAX
] __initdata
;
493 static struct e820entry new_bios
[E820MAX
] __initdata
;
494 struct change_member
*change_tmp
;
495 unsigned long current_type
, last_type
;
496 unsigned long long last_addr
;
497 int chgidx
, still_changing
;
500 int old_nr
, new_nr
, chg_nr
;
504 Visually we're performing the following
505 (1,2,3,4 = memory types)...
507 Sample memory map (w/overlaps):
508 ____22__________________
509 ______________________4_
510 ____1111________________
511 _44_____________________
512 11111111________________
513 ____________________33__
514 ___________44___________
515 __________33333_________
516 ______________22________
517 ___________________2222_
518 _________111111111______
519 _____________________11_
520 _________________4______
522 Sanitized equivalent (no overlap):
523 1_______________________
524 _44_____________________
525 ___1____________________
526 ____22__________________
527 ______11________________
528 _________1______________
529 __________3_____________
530 ___________44___________
531 _____________33_________
532 _______________2________
533 ________________1_______
534 _________________4______
535 ___________________2____
536 ____________________33__
537 ______________________4_
540 /* if there's only one memory region, don't bother */
546 /* bail out if we find any unreasonable addresses in bios map */
547 for (i
= 0; i
< old_nr
; i
++)
548 if (biosmap
[i
].addr
+ biosmap
[i
].size
< biosmap
[i
].addr
)
551 /* create pointers for initial change-point information (for sorting) */
552 for (i
= 0; i
< 2 * old_nr
; i
++)
553 change_point
[i
] = &change_point_list
[i
];
555 /* record all known change-points (starting and ending addresses),
556 omitting those that are for empty memory regions */
558 for (i
= 0; i
< old_nr
; i
++) {
559 if (biosmap
[i
].size
!= 0) {
560 change_point
[chgidx
]->addr
= biosmap
[i
].addr
;
561 change_point
[chgidx
++]->pbios
= &biosmap
[i
];
562 change_point
[chgidx
]->addr
= biosmap
[i
].addr
+
564 change_point
[chgidx
++]->pbios
= &biosmap
[i
];
569 /* sort change-point list by memory addresses (low -> high) */
571 while (still_changing
) {
573 for (i
= 1; i
< chg_nr
; i
++) {
574 unsigned long long curaddr
, lastaddr
;
575 unsigned long long curpbaddr
, lastpbaddr
;
577 curaddr
= change_point
[i
]->addr
;
578 lastaddr
= change_point
[i
- 1]->addr
;
579 curpbaddr
= change_point
[i
]->pbios
->addr
;
580 lastpbaddr
= change_point
[i
- 1]->pbios
->addr
;
583 * swap entries, when:
585 * curaddr > lastaddr or
586 * curaddr == lastaddr and curaddr == curpbaddr and
587 * lastaddr != lastpbaddr
589 if (curaddr
< lastaddr
||
590 (curaddr
== lastaddr
&& curaddr
== curpbaddr
&&
591 lastaddr
!= lastpbaddr
)) {
592 change_tmp
= change_point
[i
];
593 change_point
[i
] = change_point
[i
-1];
594 change_point
[i
-1] = change_tmp
;
600 /* create a new bios memory map, removing overlaps */
601 overlap_entries
= 0; /* number of entries in the overlap table */
602 new_bios_entry
= 0; /* index for creating new bios map entries */
603 last_type
= 0; /* start with undefined memory type */
604 last_addr
= 0; /* start with 0 as last starting address */
606 /* loop through change-points, determining affect on the new bios map */
607 for (chgidx
= 0; chgidx
< chg_nr
; chgidx
++) {
608 /* keep track of all overlapping bios entries */
609 if (change_point
[chgidx
]->addr
==
610 change_point
[chgidx
]->pbios
->addr
) {
612 * add map entry to overlap list (> 1 entry
613 * implies an overlap)
615 overlap_list
[overlap_entries
++] =
616 change_point
[chgidx
]->pbios
;
619 * remove entry from list (order independent,
622 for (i
= 0; i
< overlap_entries
; i
++) {
623 if (overlap_list
[i
] ==
624 change_point
[chgidx
]->pbios
)
626 overlap_list
[overlap_entries
-1];
631 * if there are overlapping entries, decide which
632 * "type" to use (larger value takes precedence --
633 * 1=usable, 2,3,4,4+=unusable)
636 for (i
= 0; i
< overlap_entries
; i
++)
637 if (overlap_list
[i
]->type
> current_type
)
638 current_type
= overlap_list
[i
]->type
;
640 * continue building up new bios map based on this
643 if (current_type
!= last_type
) {
644 if (last_type
!= 0) {
645 new_bios
[new_bios_entry
].size
=
646 change_point
[chgidx
]->addr
- last_addr
;
648 * move forward only if the new size
651 if (new_bios
[new_bios_entry
].size
!= 0)
653 * no more space left for new
656 if (++new_bios_entry
>= E820MAX
)
659 if (current_type
!= 0) {
660 new_bios
[new_bios_entry
].addr
=
661 change_point
[chgidx
]->addr
;
662 new_bios
[new_bios_entry
].type
= current_type
;
663 last_addr
= change_point
[chgidx
]->addr
;
665 last_type
= current_type
;
668 /* retain count for new bios entries */
669 new_nr
= new_bios_entry
;
671 /* copy new bios mapping into original location */
672 memcpy(biosmap
, new_bios
, new_nr
* sizeof(struct e820entry
));
679 * Copy the BIOS e820 map into a safe place.
681 * Sanity-check it while we're at it..
683 * If we're lucky and live on a modern system, the setup code
684 * will have given us a memory map that we can use to properly
685 * set up memory. If we aren't, we'll fake a memory map.
687 static int __init
copy_e820_map(struct e820entry
*biosmap
, int nr_map
)
689 /* Only one memory region (or negative)? Ignore it */
694 u64 start
= biosmap
->addr
;
695 u64 size
= biosmap
->size
;
696 u64 end
= start
+ size
;
697 u32 type
= biosmap
->type
;
699 /* Overflow in 64 bits? Ignore the memory map. */
703 add_memory_region(start
, size
, type
);
704 } while (biosmap
++, --nr_map
);
708 static void early_panic(char *msg
)
714 /* We're not void only for x86 32-bit compat */
715 char * __init
machine_specific_memory_setup(void)
717 char *who
= "BIOS-e820";
719 * Try to copy the BIOS-supplied E820-map.
721 * Otherwise fake a memory map; one section from 0k->640k,
722 * the next section from 1mb->appropriate_mem_k
724 sanitize_e820_map(boot_params
.e820_map
, &boot_params
.e820_entries
);
725 if (copy_e820_map(boot_params
.e820_map
, boot_params
.e820_entries
) < 0)
726 early_panic("Cannot find a valid memory map");
727 printk(KERN_INFO
"BIOS-provided physical RAM map:\n");
730 /* In case someone cares... */
734 static int __init
parse_memopt(char *p
)
738 end_user_pfn
= memparse(p
, &p
);
739 end_user_pfn
>>= PAGE_SHIFT
;
742 early_param("mem", parse_memopt
);
744 static int userdef __initdata
;
746 static int __init
parse_memmap_opt(char *p
)
749 unsigned long long start_at
, mem_size
;
751 if (!strcmp(p
, "exactmap")) {
752 #ifdef CONFIG_CRASH_DUMP
754 * If we are doing a crash dump, we still need to know
755 * the real mem size before original memory map is
758 e820_register_active_regions(0, 0, -1UL);
759 saved_max_pfn
= e820_end_of_ram();
760 remove_all_active_ranges();
769 mem_size
= memparse(p
, &p
);
775 start_at
= memparse(p
+1, &p
);
776 add_memory_region(start_at
, mem_size
, E820_RAM
);
777 } else if (*p
== '#') {
778 start_at
= memparse(p
+1, &p
);
779 add_memory_region(start_at
, mem_size
, E820_ACPI
);
780 } else if (*p
== '$') {
781 start_at
= memparse(p
+1, &p
);
782 add_memory_region(start_at
, mem_size
, E820_RESERVED
);
784 end_user_pfn
= (mem_size
>> PAGE_SHIFT
);
786 return *p
== '\0' ? 0 : -EINVAL
;
788 early_param("memmap", parse_memmap_opt
);
790 void __init
finish_e820_parsing(void)
793 char nr
= e820
.nr_map
;
795 if (sanitize_e820_map(e820
.map
, &nr
) < 0)
796 early_panic("Invalid user supplied memory map");
799 printk(KERN_INFO
"user-defined physical RAM map:\n");
800 e820_print_map("user");
804 void __init
update_memory_range(u64 start
, u64 size
, unsigned old_type
,
809 BUG_ON(old_type
== new_type
);
811 for (i
= 0; i
< e820
.nr_map
; i
++) {
812 struct e820entry
*ei
= &e820
.map
[i
];
813 u64 final_start
, final_end
;
814 if (ei
->type
!= old_type
)
816 /* totally covered? */
817 if (ei
->addr
>= start
&& ei
->size
<= size
) {
821 /* partially covered */
822 final_start
= max(start
, ei
->addr
);
823 final_end
= min(start
+ size
, ei
->addr
+ ei
->size
);
824 if (final_start
>= final_end
)
826 add_memory_region(final_start
, final_end
- final_start
,
831 void __init
update_e820(void)
835 nr_map
= e820
.nr_map
;
836 if (sanitize_e820_map(e820
.map
, &nr_map
))
838 e820
.nr_map
= nr_map
;
839 printk(KERN_INFO
"modified physical RAM map:\n");
840 e820_print_map("modified");
843 unsigned long pci_mem_start
= 0xaeedbabe;
844 EXPORT_SYMBOL(pci_mem_start
);
847 * Search for the biggest gap in the low 32 bits of the e820
848 * memory space. We pass this space to PCI to assign MMIO resources
849 * for hotplug or unconfigured devices in.
850 * Hopefully the BIOS let enough space left.
852 __init
void e820_setup_gap(void)
854 unsigned long gapstart
, gapsize
, round
;
859 last
= 0x100000000ull
;
860 gapstart
= 0x10000000;
864 unsigned long long start
= e820
.map
[i
].addr
;
865 unsigned long long end
= start
+ e820
.map
[i
].size
;
868 * Since "last" is at most 4GB, we know we'll
869 * fit in 32 bits if this condition is true
872 unsigned long gap
= last
- end
;
885 gapstart
= (end_pfn
<< PAGE_SHIFT
) + 1024*1024;
886 printk(KERN_ERR
"PCI: Warning: Cannot find a gap in the 32bit "
888 KERN_ERR
"PCI: Unassigned devices with 32bit resource "
889 "registers may break!\n");
893 * See how much we want to round up: start off with
894 * rounding to the next 1MB area.
897 while ((gapsize
>> 4) > round
)
899 /* Fun with two's complement */
900 pci_mem_start
= (gapstart
+ round
) & -round
;
903 "Allocating PCI resources starting at %lx (gap: %lx:%lx)\n",
904 pci_mem_start
, gapstart
, gapsize
);
907 int __init
arch_get_ram_range(int slot
, u64
*addr
, u64
*size
)
911 if (slot
< 0 || slot
>= e820
.nr_map
)
913 for (i
= slot
; i
< e820
.nr_map
; i
++) {
914 if (e820
.map
[i
].type
!= E820_RAM
)
918 if (i
== e820
.nr_map
|| e820
.map
[i
].addr
> (max_pfn
<< PAGE_SHIFT
))
920 *addr
= e820
.map
[i
].addr
;
921 *size
= min_t(u64
, e820
.map
[i
].size
+ e820
.map
[i
].addr
,
922 max_pfn
<< PAGE_SHIFT
) - *addr
;