aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/e820_32.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/e820_32.c')
-rw-r--r--arch/x86/kernel/e820_32.c944
1 files changed, 944 insertions, 0 deletions
diff --git a/arch/x86/kernel/e820_32.c b/arch/x86/kernel/e820_32.c
new file mode 100644
index 000000000000..3c86b979a40a
--- /dev/null
+++ b/arch/x86/kernel/e820_32.c
@@ -0,0 +1,944 @@
1#include <linux/kernel.h>
2#include <linux/types.h>
3#include <linux/init.h>
4#include <linux/bootmem.h>
5#include <linux/ioport.h>
6#include <linux/string.h>
7#include <linux/kexec.h>
8#include <linux/module.h>
9#include <linux/mm.h>
10#include <linux/efi.h>
11#include <linux/pfn.h>
12#include <linux/uaccess.h>
13#include <linux/suspend.h>
14
15#include <asm/pgtable.h>
16#include <asm/page.h>
17#include <asm/e820.h>
18#include <asm/setup.h>
19
20#ifdef CONFIG_EFI
21int efi_enabled = 0;
22EXPORT_SYMBOL(efi_enabled);
23#endif
24
25struct e820map e820;
26struct change_member {
27 struct e820entry *pbios; /* pointer to original bios entry */
28 unsigned long long addr; /* address for this change point */
29};
30static struct change_member change_point_list[2*E820MAX] __initdata;
31static struct change_member *change_point[2*E820MAX] __initdata;
32static struct e820entry *overlap_list[E820MAX] __initdata;
33static struct e820entry new_bios[E820MAX] __initdata;
34/* For PCI or other memory-mapped resources */
35unsigned long pci_mem_start = 0x10000000;
36#ifdef CONFIG_PCI
37EXPORT_SYMBOL(pci_mem_start);
38#endif
39extern int user_defined_memmap;
40struct resource data_resource = {
41 .name = "Kernel data",
42 .start = 0,
43 .end = 0,
44 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
45};
46
47struct resource code_resource = {
48 .name = "Kernel code",
49 .start = 0,
50 .end = 0,
51 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
52};
53
54static struct resource system_rom_resource = {
55 .name = "System ROM",
56 .start = 0xf0000,
57 .end = 0xfffff,
58 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
59};
60
61static struct resource extension_rom_resource = {
62 .name = "Extension ROM",
63 .start = 0xe0000,
64 .end = 0xeffff,
65 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
66};
67
68static struct resource adapter_rom_resources[] = { {
69 .name = "Adapter ROM",
70 .start = 0xc8000,
71 .end = 0,
72 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
73}, {
74 .name = "Adapter ROM",
75 .start = 0,
76 .end = 0,
77 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
78}, {
79 .name = "Adapter ROM",
80 .start = 0,
81 .end = 0,
82 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
83}, {
84 .name = "Adapter ROM",
85 .start = 0,
86 .end = 0,
87 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
88}, {
89 .name = "Adapter ROM",
90 .start = 0,
91 .end = 0,
92 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
93}, {
94 .name = "Adapter ROM",
95 .start = 0,
96 .end = 0,
97 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
98} };
99
100static struct resource video_rom_resource = {
101 .name = "Video ROM",
102 .start = 0xc0000,
103 .end = 0xc7fff,
104 .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM
105};
106
107static struct resource video_ram_resource = {
108 .name = "Video RAM area",
109 .start = 0xa0000,
110 .end = 0xbffff,
111 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
112};
113
114static struct resource standard_io_resources[] = { {
115 .name = "dma1",
116 .start = 0x0000,
117 .end = 0x001f,
118 .flags = IORESOURCE_BUSY | IORESOURCE_IO
119}, {
120 .name = "pic1",
121 .start = 0x0020,
122 .end = 0x0021,
123 .flags = IORESOURCE_BUSY | IORESOURCE_IO
124}, {
125 .name = "timer0",
126 .start = 0x0040,
127 .end = 0x0043,
128 .flags = IORESOURCE_BUSY | IORESOURCE_IO
129}, {
130 .name = "timer1",
131 .start = 0x0050,
132 .end = 0x0053,
133 .flags = IORESOURCE_BUSY | IORESOURCE_IO
134}, {
135 .name = "keyboard",
136 .start = 0x0060,
137 .end = 0x006f,
138 .flags = IORESOURCE_BUSY | IORESOURCE_IO
139}, {
140 .name = "dma page reg",
141 .start = 0x0080,
142 .end = 0x008f,
143 .flags = IORESOURCE_BUSY | IORESOURCE_IO
144}, {
145 .name = "pic2",
146 .start = 0x00a0,
147 .end = 0x00a1,
148 .flags = IORESOURCE_BUSY | IORESOURCE_IO
149}, {
150 .name = "dma2",
151 .start = 0x00c0,
152 .end = 0x00df,
153 .flags = IORESOURCE_BUSY | IORESOURCE_IO
154}, {
155 .name = "fpu",
156 .start = 0x00f0,
157 .end = 0x00ff,
158 .flags = IORESOURCE_BUSY | IORESOURCE_IO
159} };
160
161#define ROMSIGNATURE 0xaa55
162
163static int __init romsignature(const unsigned char *rom)
164{
165 const unsigned short * const ptr = (const unsigned short *)rom;
166 unsigned short sig;
167
168 return probe_kernel_address(ptr, sig) == 0 && sig == ROMSIGNATURE;
169}
170
171static int __init romchecksum(const unsigned char *rom, unsigned long length)
172{
173 unsigned char sum, c;
174
175 for (sum = 0; length && probe_kernel_address(rom++, c) == 0; length--)
176 sum += c;
177 return !length && !sum;
178}
179
180static void __init probe_roms(void)
181{
182 const unsigned char *rom;
183 unsigned long start, length, upper;
184 unsigned char c;
185 int i;
186
187 /* video rom */
188 upper = adapter_rom_resources[0].start;
189 for (start = video_rom_resource.start; start < upper; start += 2048) {
190 rom = isa_bus_to_virt(start);
191 if (!romsignature(rom))
192 continue;
193
194 video_rom_resource.start = start;
195
196 if (probe_kernel_address(rom + 2, c) != 0)
197 continue;
198
199 /* 0 < length <= 0x7f * 512, historically */
200 length = c * 512;
201
202 /* if checksum okay, trust length byte */
203 if (length && romchecksum(rom, length))
204 video_rom_resource.end = start + length - 1;
205
206 request_resource(&iomem_resource, &video_rom_resource);
207 break;
208 }
209
210 start = (video_rom_resource.end + 1 + 2047) & ~2047UL;
211 if (start < upper)
212 start = upper;
213
214 /* system rom */
215 request_resource(&iomem_resource, &system_rom_resource);
216 upper = system_rom_resource.start;
217
218 /* check for extension rom (ignore length byte!) */
219 rom = isa_bus_to_virt(extension_rom_resource.start);
220 if (romsignature(rom)) {
221 length = extension_rom_resource.end - extension_rom_resource.start + 1;
222 if (romchecksum(rom, length)) {
223 request_resource(&iomem_resource, &extension_rom_resource);
224 upper = extension_rom_resource.start;
225 }
226 }
227
228 /* check for adapter roms on 2k boundaries */
229 for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) {
230 rom = isa_bus_to_virt(start);
231 if (!romsignature(rom))
232 continue;
233
234 if (probe_kernel_address(rom + 2, c) != 0)
235 continue;
236
237 /* 0 < length <= 0x7f * 512, historically */
238 length = c * 512;
239
240 /* but accept any length that fits if checksum okay */
241 if (!length || start + length > upper || !romchecksum(rom, length))
242 continue;
243
244 adapter_rom_resources[i].start = start;
245 adapter_rom_resources[i].end = start + length - 1;
246 request_resource(&iomem_resource, &adapter_rom_resources[i]);
247
248 start = adapter_rom_resources[i++].end & ~2047UL;
249 }
250}
251
252/*
253 * Request address space for all standard RAM and ROM resources
254 * and also for regions reported as reserved by the e820.
255 */
256static void __init
257legacy_init_iomem_resources(struct resource *code_resource, struct resource *data_resource)
258{
259 int i;
260
261 probe_roms();
262 for (i = 0; i < e820.nr_map; i++) {
263 struct resource *res;
264#ifndef CONFIG_RESOURCES_64BIT
265 if (e820.map[i].addr + e820.map[i].size > 0x100000000ULL)
266 continue;
267#endif
268 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
269 switch (e820.map[i].type) {
270 case E820_RAM: res->name = "System RAM"; break;
271 case E820_ACPI: res->name = "ACPI Tables"; break;
272 case E820_NVS: res->name = "ACPI Non-volatile Storage"; break;
273 default: res->name = "reserved";
274 }
275 res->start = e820.map[i].addr;
276 res->end = res->start + e820.map[i].size - 1;
277 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
278 if (request_resource(&iomem_resource, res)) {
279 kfree(res);
280 continue;
281 }
282 if (e820.map[i].type == E820_RAM) {
283 /*
284 * We don't know which RAM region contains kernel data,
285 * so we try it repeatedly and let the resource manager
286 * test it.
287 */
288 request_resource(res, code_resource);
289 request_resource(res, data_resource);
290#ifdef CONFIG_KEXEC
291 request_resource(res, &crashk_res);
292#endif
293 }
294 }
295}
296
297/*
298 * Request address space for all standard resources
299 *
300 * This is called just before pcibios_init(), which is also a
301 * subsys_initcall, but is linked in later (in arch/i386/pci/common.c).
302 */
303static int __init request_standard_resources(void)
304{
305 int i;
306
307 printk("Setting up standard PCI resources\n");
308 if (efi_enabled)
309 efi_initialize_iomem_resources(&code_resource, &data_resource);
310 else
311 legacy_init_iomem_resources(&code_resource, &data_resource);
312
313 /* EFI systems may still have VGA */
314 request_resource(&iomem_resource, &video_ram_resource);
315
316 /* request I/O space for devices used on all i[345]86 PCs */
317 for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
318 request_resource(&ioport_resource, &standard_io_resources[i]);
319 return 0;
320}
321
322subsys_initcall(request_standard_resources);
323
324#if defined(CONFIG_PM) && defined(CONFIG_HIBERNATION)
325/**
326 * e820_mark_nosave_regions - Find the ranges of physical addresses that do not
327 * correspond to e820 RAM areas and mark the corresponding pages as nosave for
328 * hibernation.
329 *
330 * This function requires the e820 map to be sorted and without any
331 * overlapping entries and assumes the first e820 area to be RAM.
332 */
333void __init e820_mark_nosave_regions(void)
334{
335 int i;
336 unsigned long pfn;
337
338 pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
339 for (i = 1; i < e820.nr_map; i++) {
340 struct e820entry *ei = &e820.map[i];
341
342 if (pfn < PFN_UP(ei->addr))
343 register_nosave_region(pfn, PFN_UP(ei->addr));
344
345 pfn = PFN_DOWN(ei->addr + ei->size);
346 if (ei->type != E820_RAM)
347 register_nosave_region(PFN_UP(ei->addr), pfn);
348
349 if (pfn >= max_low_pfn)
350 break;
351 }
352}
353#endif
354
355void __init add_memory_region(unsigned long long start,
356 unsigned long long size, int type)
357{
358 int x;
359
360 if (!efi_enabled) {
361 x = e820.nr_map;
362
363 if (x == E820MAX) {
364 printk(KERN_ERR "Ooops! Too many entries in the memory map!\n");
365 return;
366 }
367
368 e820.map[x].addr = start;
369 e820.map[x].size = size;
370 e820.map[x].type = type;
371 e820.nr_map++;
372 }
373} /* add_memory_region */
374
375/*
376 * Sanitize the BIOS e820 map.
377 *
378 * Some e820 responses include overlapping entries. The following
379 * replaces the original e820 map with a new one, removing overlaps.
380 *
381 */
382int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
383{
384 struct change_member *change_tmp;
385 unsigned long current_type, last_type;
386 unsigned long long last_addr;
387 int chgidx, still_changing;
388 int overlap_entries;
389 int new_bios_entry;
390 int old_nr, new_nr, chg_nr;
391 int i;
392
393 /*
394 Visually we're performing the following (1,2,3,4 = memory types)...
395
396 Sample memory map (w/overlaps):
397 ____22__________________
398 ______________________4_
399 ____1111________________
400 _44_____________________
401 11111111________________
402 ____________________33__
403 ___________44___________
404 __________33333_________
405 ______________22________
406 ___________________2222_
407 _________111111111______
408 _____________________11_
409 _________________4______
410
411 Sanitized equivalent (no overlap):
412 1_______________________
413 _44_____________________
414 ___1____________________
415 ____22__________________
416 ______11________________
417 _________1______________
418 __________3_____________
419 ___________44___________
420 _____________33_________
421 _______________2________
422 ________________1_______
423 _________________4______
424 ___________________2____
425 ____________________33__
426 ______________________4_
427 */
428 /* if there's only one memory region, don't bother */
429 if (*pnr_map < 2) {
430 return -1;
431 }
432
433 old_nr = *pnr_map;
434
435 /* bail out if we find any unreasonable addresses in bios map */
436 for (i=0; i<old_nr; i++)
437 if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) {
438 return -1;
439 }
440
441 /* create pointers for initial change-point information (for sorting) */
442 for (i=0; i < 2*old_nr; i++)
443 change_point[i] = &change_point_list[i];
444
445 /* record all known change-points (starting and ending addresses),
446 omitting those that are for empty memory regions */
447 chgidx = 0;
448 for (i=0; i < old_nr; i++) {
449 if (biosmap[i].size != 0) {
450 change_point[chgidx]->addr = biosmap[i].addr;
451 change_point[chgidx++]->pbios = &biosmap[i];
452 change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size;
453 change_point[chgidx++]->pbios = &biosmap[i];
454 }
455 }
456 chg_nr = chgidx; /* true number of change-points */
457
458 /* sort change-point list by memory addresses (low -> high) */
459 still_changing = 1;
460 while (still_changing) {
461 still_changing = 0;
462 for (i=1; i < chg_nr; i++) {
463 /* if <current_addr> > <last_addr>, swap */
464 /* or, if current=<start_addr> & last=<end_addr>, swap */
465 if ((change_point[i]->addr < change_point[i-1]->addr) ||
466 ((change_point[i]->addr == change_point[i-1]->addr) &&
467 (change_point[i]->addr == change_point[i]->pbios->addr) &&
468 (change_point[i-1]->addr != change_point[i-1]->pbios->addr))
469 )
470 {
471 change_tmp = change_point[i];
472 change_point[i] = change_point[i-1];
473 change_point[i-1] = change_tmp;
474 still_changing=1;
475 }
476 }
477 }
478
479 /* create a new bios memory map, removing overlaps */
480 overlap_entries=0; /* number of entries in the overlap table */
481 new_bios_entry=0; /* index for creating new bios map entries */
482 last_type = 0; /* start with undefined memory type */
483 last_addr = 0; /* start with 0 as last starting address */
484 /* loop through change-points, determining affect on the new bios map */
485 for (chgidx=0; chgidx < chg_nr; chgidx++)
486 {
487 /* keep track of all overlapping bios entries */
488 if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr)
489 {
490 /* add map entry to overlap list (> 1 entry implies an overlap) */
491 overlap_list[overlap_entries++]=change_point[chgidx]->pbios;
492 }
493 else
494 {
495 /* remove entry from list (order independent, so swap with last) */
496 for (i=0; i<overlap_entries; i++)
497 {
498 if (overlap_list[i] == change_point[chgidx]->pbios)
499 overlap_list[i] = overlap_list[overlap_entries-1];
500 }
501 overlap_entries--;
502 }
503 /* if there are overlapping entries, decide which "type" to use */
504 /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */
505 current_type = 0;
506 for (i=0; i<overlap_entries; i++)
507 if (overlap_list[i]->type > current_type)
508 current_type = overlap_list[i]->type;
509 /* continue building up new bios map based on this information */
510 if (current_type != last_type) {
511 if (last_type != 0) {
512 new_bios[new_bios_entry].size =
513 change_point[chgidx]->addr - last_addr;
514 /* move forward only if the new size was non-zero */
515 if (new_bios[new_bios_entry].size != 0)
516 if (++new_bios_entry >= E820MAX)
517 break; /* no more space left for new bios entries */
518 }
519 if (current_type != 0) {
520 new_bios[new_bios_entry].addr = change_point[chgidx]->addr;
521 new_bios[new_bios_entry].type = current_type;
522 last_addr=change_point[chgidx]->addr;
523 }
524 last_type = current_type;
525 }
526 }
527 new_nr = new_bios_entry; /* retain count for new bios entries */
528
529 /* copy new bios mapping into original location */
530 memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry));
531 *pnr_map = new_nr;
532
533 return 0;
534}
535
536/*
537 * Copy the BIOS e820 map into a safe place.
538 *
539 * Sanity-check it while we're at it..
540 *
541 * If we're lucky and live on a modern system, the setup code
542 * will have given us a memory map that we can use to properly
543 * set up memory. If we aren't, we'll fake a memory map.
544 *
545 * We check to see that the memory map contains at least 2 elements
546 * before we'll use it, because the detection code in setup.S may
547 * not be perfect and most every PC known to man has two memory
548 * regions: one from 0 to 640k, and one from 1mb up. (The IBM
549 * thinkpad 560x, for example, does not cooperate with the memory
550 * detection code.)
551 */
552int __init copy_e820_map(struct e820entry * biosmap, int nr_map)
553{
554 /* Only one memory region (or negative)? Ignore it */
555 if (nr_map < 2)
556 return -1;
557
558 do {
559 unsigned long long start = biosmap->addr;
560 unsigned long long size = biosmap->size;
561 unsigned long long end = start + size;
562 unsigned long type = biosmap->type;
563
564 /* Overflow in 64 bits? Ignore the memory map. */
565 if (start > end)
566 return -1;
567
568 /*
569 * Some BIOSes claim RAM in the 640k - 1M region.
570 * Not right. Fix it up.
571 */
572 if (type == E820_RAM) {
573 if (start < 0x100000ULL && end > 0xA0000ULL) {
574 if (start < 0xA0000ULL)
575 add_memory_region(start, 0xA0000ULL-start, type);
576 if (end <= 0x100000ULL)
577 continue;
578 start = 0x100000ULL;
579 size = end - start;
580 }
581 }
582 add_memory_region(start, size, type);
583 } while (biosmap++,--nr_map);
584 return 0;
585}
586
587/*
588 * Callback for efi_memory_walk.
589 */
590static int __init
591efi_find_max_pfn(unsigned long start, unsigned long end, void *arg)
592{
593 unsigned long *max_pfn = arg, pfn;
594
595 if (start < end) {
596 pfn = PFN_UP(end -1);
597 if (pfn > *max_pfn)
598 *max_pfn = pfn;
599 }
600 return 0;
601}
602
603static int __init
604efi_memory_present_wrapper(unsigned long start, unsigned long end, void *arg)
605{
606 memory_present(0, PFN_UP(start), PFN_DOWN(end));
607 return 0;
608}
609
610/*
611 * Find the highest page frame number we have available
612 */
613void __init find_max_pfn(void)
614{
615 int i;
616
617 max_pfn = 0;
618 if (efi_enabled) {
619 efi_memmap_walk(efi_find_max_pfn, &max_pfn);
620 efi_memmap_walk(efi_memory_present_wrapper, NULL);
621 return;
622 }
623
624 for (i = 0; i < e820.nr_map; i++) {
625 unsigned long start, end;
626 /* RAM? */
627 if (e820.map[i].type != E820_RAM)
628 continue;
629 start = PFN_UP(e820.map[i].addr);
630 end = PFN_DOWN(e820.map[i].addr + e820.map[i].size);
631 if (start >= end)
632 continue;
633 if (end > max_pfn)
634 max_pfn = end;
635 memory_present(0, start, end);
636 }
637}
638
639/*
640 * Free all available memory for boot time allocation. Used
641 * as a callback function by efi_memory_walk()
642 */
643
644static int __init
645free_available_memory(unsigned long start, unsigned long end, void *arg)
646{
647 /* check max_low_pfn */
648 if (start >= (max_low_pfn << PAGE_SHIFT))
649 return 0;
650 if (end >= (max_low_pfn << PAGE_SHIFT))
651 end = max_low_pfn << PAGE_SHIFT;
652 if (start < end)
653 free_bootmem(start, end - start);
654
655 return 0;
656}
657/*
658 * Register fully available low RAM pages with the bootmem allocator.
659 */
660void __init register_bootmem_low_pages(unsigned long max_low_pfn)
661{
662 int i;
663
664 if (efi_enabled) {
665 efi_memmap_walk(free_available_memory, NULL);
666 return;
667 }
668 for (i = 0; i < e820.nr_map; i++) {
669 unsigned long curr_pfn, last_pfn, size;
670 /*
671 * Reserve usable low memory
672 */
673 if (e820.map[i].type != E820_RAM)
674 continue;
675 /*
676 * We are rounding up the start address of usable memory:
677 */
678 curr_pfn = PFN_UP(e820.map[i].addr);
679 if (curr_pfn >= max_low_pfn)
680 continue;
681 /*
682 * ... and at the end of the usable range downwards:
683 */
684 last_pfn = PFN_DOWN(e820.map[i].addr + e820.map[i].size);
685
686 if (last_pfn > max_low_pfn)
687 last_pfn = max_low_pfn;
688
689 /*
690 * .. finally, did all the rounding and playing
691 * around just make the area go away?
692 */
693 if (last_pfn <= curr_pfn)
694 continue;
695
696 size = last_pfn - curr_pfn;
697 free_bootmem(PFN_PHYS(curr_pfn), PFN_PHYS(size));
698 }
699}
700
701void __init e820_register_memory(void)
702{
703 unsigned long gapstart, gapsize, round;
704 unsigned long long last;
705 int i;
706
707 /*
708 * Search for the bigest gap in the low 32 bits of the e820
709 * memory space.
710 */
711 last = 0x100000000ull;
712 gapstart = 0x10000000;
713 gapsize = 0x400000;
714 i = e820.nr_map;
715 while (--i >= 0) {
716 unsigned long long start = e820.map[i].addr;
717 unsigned long long end = start + e820.map[i].size;
718
719 /*
720 * Since "last" is at most 4GB, we know we'll
721 * fit in 32 bits if this condition is true
722 */
723 if (last > end) {
724 unsigned long gap = last - end;
725
726 if (gap > gapsize) {
727 gapsize = gap;
728 gapstart = end;
729 }
730 }
731 if (start < last)
732 last = start;
733 }
734
735 /*
736 * See how much we want to round up: start off with
737 * rounding to the next 1MB area.
738 */
739 round = 0x100000;
740 while ((gapsize >> 4) > round)
741 round += round;
742 /* Fun with two's complement */
743 pci_mem_start = (gapstart + round) & -round;
744
745 printk("Allocating PCI resources starting at %08lx (gap: %08lx:%08lx)\n",
746 pci_mem_start, gapstart, gapsize);
747}
748
749void __init print_memory_map(char *who)
750{
751 int i;
752
753 for (i = 0; i < e820.nr_map; i++) {
754 printk(" %s: %016Lx - %016Lx ", who,
755 e820.map[i].addr,
756 e820.map[i].addr + e820.map[i].size);
757 switch (e820.map[i].type) {
758 case E820_RAM: printk("(usable)\n");
759 break;
760 case E820_RESERVED:
761 printk("(reserved)\n");
762 break;
763 case E820_ACPI:
764 printk("(ACPI data)\n");
765 break;
766 case E820_NVS:
767 printk("(ACPI NVS)\n");
768 break;
769 default: printk("type %u\n", e820.map[i].type);
770 break;
771 }
772 }
773}
774
775static __init __always_inline void efi_limit_regions(unsigned long long size)
776{
777 unsigned long long current_addr = 0;
778 efi_memory_desc_t *md, *next_md;
779 void *p, *p1;
780 int i, j;
781
782 j = 0;
783 p1 = memmap.map;
784 for (p = p1, i = 0; p < memmap.map_end; p += memmap.desc_size, i++) {
785 md = p;
786 next_md = p1;
787 current_addr = md->phys_addr +
788 PFN_PHYS(md->num_pages);
789 if (is_available_memory(md)) {
790 if (md->phys_addr >= size) continue;
791 memcpy(next_md, md, memmap.desc_size);
792 if (current_addr >= size) {
793 next_md->num_pages -=
794 PFN_UP(current_addr-size);
795 }
796 p1 += memmap.desc_size;
797 next_md = p1;
798 j++;
799 } else if ((md->attribute & EFI_MEMORY_RUNTIME) ==
800 EFI_MEMORY_RUNTIME) {
801 /* In order to make runtime services
802 * available we have to include runtime
803 * memory regions in memory map */
804 memcpy(next_md, md, memmap.desc_size);
805 p1 += memmap.desc_size;
806 next_md = p1;
807 j++;
808 }
809 }
810 memmap.nr_map = j;
811 memmap.map_end = memmap.map +
812 (memmap.nr_map * memmap.desc_size);
813}
814
815void __init limit_regions(unsigned long long size)
816{
817 unsigned long long current_addr;
818 int i;
819
820 print_memory_map("limit_regions start");
821 if (efi_enabled) {
822 efi_limit_regions(size);
823 return;
824 }
825 for (i = 0; i < e820.nr_map; i++) {
826 current_addr = e820.map[i].addr + e820.map[i].size;
827 if (current_addr < size)
828 continue;
829
830 if (e820.map[i].type != E820_RAM)
831 continue;
832
833 if (e820.map[i].addr >= size) {
834 /*
835 * This region starts past the end of the
836 * requested size, skip it completely.
837 */
838 e820.nr_map = i;
839 } else {
840 e820.nr_map = i + 1;
841 e820.map[i].size -= current_addr - size;
842 }
843 print_memory_map("limit_regions endfor");
844 return;
845 }
846 print_memory_map("limit_regions endfunc");
847}
848
849/*
850 * This function checks if any part of the range <start,end> is mapped
851 * with type.
852 */
853int
854e820_any_mapped(u64 start, u64 end, unsigned type)
855{
856 int i;
857 for (i = 0; i < e820.nr_map; i++) {
858 const struct e820entry *ei = &e820.map[i];
859 if (type && ei->type != type)
860 continue;
861 if (ei->addr >= end || ei->addr + ei->size <= start)
862 continue;
863 return 1;
864 }
865 return 0;
866}
867EXPORT_SYMBOL_GPL(e820_any_mapped);
868
869 /*
870 * This function checks if the entire range <start,end> is mapped with type.
871 *
872 * Note: this function only works correct if the e820 table is sorted and
873 * not-overlapping, which is the case
874 */
875int __init
876e820_all_mapped(unsigned long s, unsigned long e, unsigned type)
877{
878 u64 start = s;
879 u64 end = e;
880 int i;
881 for (i = 0; i < e820.nr_map; i++) {
882 struct e820entry *ei = &e820.map[i];
883 if (type && ei->type != type)
884 continue;
885 /* is the region (part) in overlap with the current region ?*/
886 if (ei->addr >= end || ei->addr + ei->size <= start)
887 continue;
888 /* if the region is at the beginning of <start,end> we move
889 * start to the end of the region since it's ok until there
890 */
891 if (ei->addr <= start)
892 start = ei->addr + ei->size;
893 /* if start is now at or beyond end, we're done, full
894 * coverage */
895 if (start >= end)
896 return 1; /* we're done */
897 }
898 return 0;
899}
900
901static int __init parse_memmap(char *arg)
902{
903 if (!arg)
904 return -EINVAL;
905
906 if (strcmp(arg, "exactmap") == 0) {
907#ifdef CONFIG_CRASH_DUMP
908 /* If we are doing a crash dump, we
909 * still need to know the real mem
910 * size before original memory map is
911 * reset.
912 */
913 find_max_pfn();
914 saved_max_pfn = max_pfn;
915#endif
916 e820.nr_map = 0;
917 user_defined_memmap = 1;
918 } else {
919 /* If the user specifies memory size, we
920 * limit the BIOS-provided memory map to
921 * that size. exactmap can be used to specify
922 * the exact map. mem=number can be used to
923 * trim the existing memory map.
924 */
925 unsigned long long start_at, mem_size;
926
927 mem_size = memparse(arg, &arg);
928 if (*arg == '@') {
929 start_at = memparse(arg+1, &arg);
930 add_memory_region(start_at, mem_size, E820_RAM);
931 } else if (*arg == '#') {
932 start_at = memparse(arg+1, &arg);
933 add_memory_region(start_at, mem_size, E820_ACPI);
934 } else if (*arg == '$') {
935 start_at = memparse(arg+1, &arg);
936 add_memory_region(start_at, mem_size, E820_RESERVED);
937 } else {
938 limit_regions(mem_size);
939 user_defined_memmap = 1;
940 }
941 }
942 return 0;
943}
944early_param("memmap", parse_memmap);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-18 03:03:47 -0500