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1 /*
2 * Initialize MMU support.
3 *
4 * Copyright (C) 1998-2003 Hewlett-Packard Co
5 * David Mosberger-Tang <davidm@hpl.hp.com>
6 */
7 #include <linux/kernel.h>
8 #include <linux/init.h>
9
10 #include <linux/bootmem.h>
11 #include <linux/efi.h>
12 #include <linux/elf.h>
13 #include <linux/memblock.h>
14 #include <linux/mm.h>
15 #include <linux/mmzone.h>
16 #include <linux/module.h>
17 #include <linux/personality.h>
18 #include <linux/reboot.h>
19 #include <linux/slab.h>
20 #include <linux/swap.h>
21 #include <linux/proc_fs.h>
22 #include <linux/bitops.h>
23 #include <linux/kexec.h>
24
25 #include <asm/dma.h>
26 #include <asm/io.h>
27 #include <asm/machvec.h>
28 #include <asm/numa.h>
29 #include <asm/patch.h>
30 #include <asm/pgalloc.h>
31 #include <asm/sal.h>
32 #include <asm/sections.h>
33 #include <asm/tlb.h>
34 #include <asm/uaccess.h>
35 #include <asm/unistd.h>
36 #include <asm/mca.h>
37
38 extern void ia64_tlb_init (void);
39
40 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;
41
42 #ifdef CONFIG_VIRTUAL_MEM_MAP
43 unsigned long VMALLOC_END = VMALLOC_END_INIT;
44 EXPORT_SYMBOL(VMALLOC_END);
45 struct page *vmem_map;
46 EXPORT_SYMBOL(vmem_map);
47 #endif
48
49 struct page *zero_page_memmap_ptr; /* map entry for zero page */
50 EXPORT_SYMBOL(zero_page_memmap_ptr);
51
52 void
53 __ia64_sync_icache_dcache (pte_t pte)
54 {
55 unsigned long addr;
56 struct page *page;
57
58 page = pte_page(pte);
59 addr = (unsigned long) page_address(page);
60
61 if (test_bit(PG_arch_1, &page->flags))
62 return; /* i-cache is already coherent with d-cache */
63
64 flush_icache_range(addr, addr + (PAGE_SIZE << compound_order(page)));
65 set_bit(PG_arch_1, &page->flags); /* mark page as clean */
66 }
67
68 /*
69 * Since DMA is i-cache coherent, any (complete) pages that were written via
70 * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
71 * flush them when they get mapped into an executable vm-area.
72 */
73 void
74 dma_mark_clean(void *addr, size_t size)
75 {
76 unsigned long pg_addr, end;
77
78 pg_addr = PAGE_ALIGN((unsigned long) addr);
79 end = (unsigned long) addr + size;
80 while (pg_addr + PAGE_SIZE <= end) {
81 struct page *page = virt_to_page(pg_addr);
82 set_bit(PG_arch_1, &page->flags);
83 pg_addr += PAGE_SIZE;
84 }
85 }
86
87 inline void
88 ia64_set_rbs_bot (void)
89 {
90 unsigned long stack_size = rlimit_max(RLIMIT_STACK) & -16;
91
92 if (stack_size > MAX_USER_STACK_SIZE)
93 stack_size = MAX_USER_STACK_SIZE;
94 current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size);
95 }
96
97 /*
98 * This performs some platform-dependent address space initialization.
99 * On IA-64, we want to setup the VM area for the register backing
100 * store (which grows upwards) and install the gateway page which is
101 * used for signal trampolines, etc.
102 */
103 void
104 ia64_init_addr_space (void)
105 {
106 struct vm_area_struct *vma;
107
108 ia64_set_rbs_bot();
109
110 /*
111 * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
112 * the problem. When the process attempts to write to the register backing store
113 * for the first time, it will get a SEGFAULT in this case.
114 */
115 vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
116 if (vma) {
117 INIT_LIST_HEAD(&vma->anon_vma_chain);
118 vma->vm_mm = current->mm;
119 vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
120 vma->vm_end = vma->vm_start + PAGE_SIZE;
121 vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT;
122 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
123 down_write(&current->mm->mmap_sem);
124 if (insert_vm_struct(current->mm, vma)) {
125 up_write(&current->mm->mmap_sem);
126 kmem_cache_free(vm_area_cachep, vma);
127 return;
128 }
129 up_write(&current->mm->mmap_sem);
130 }
131
132 /* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
133 if (!(current->personality & MMAP_PAGE_ZERO)) {
134 vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
135 if (vma) {
136 INIT_LIST_HEAD(&vma->anon_vma_chain);
137 vma->vm_mm = current->mm;
138 vma->vm_end = PAGE_SIZE;
139 vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
140 vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO |
141 VM_DONTEXPAND | VM_DONTDUMP;
142 down_write(&current->mm->mmap_sem);
143 if (insert_vm_struct(current->mm, vma)) {
144 up_write(&current->mm->mmap_sem);
145 kmem_cache_free(vm_area_cachep, vma);
146 return;
147 }
148 up_write(&current->mm->mmap_sem);
149 }
150 }
151 }
152
153 void
154 free_initmem (void)
155 {
156 free_reserved_area(ia64_imva(__init_begin), ia64_imva(__init_end),
157 -1, "unused kernel");
158 }
159
160 void __init
161 free_initrd_mem (unsigned long start, unsigned long end)
162 {
163 /*
164 * EFI uses 4KB pages while the kernel can use 4KB or bigger.
165 * Thus EFI and the kernel may have different page sizes. It is
166 * therefore possible to have the initrd share the same page as
167 * the end of the kernel (given current setup).
168 *
169 * To avoid freeing/using the wrong page (kernel sized) we:
170 * - align up the beginning of initrd
171 * - align down the end of initrd
172 *
173 * | |
174 * |=============| a000
175 * | |
176 * | |
177 * | | 9000
178 * |/////////////|
179 * |/////////////|
180 * |=============| 8000
181 * |///INITRD////|
182 * |/////////////|
183 * |/////////////| 7000
184 * | |
185 * |KKKKKKKKKKKKK|
186 * |=============| 6000
187 * |KKKKKKKKKKKKK|
188 * |KKKKKKKKKKKKK|
189 * K=kernel using 8KB pages
190 *
191 * In this example, we must free page 8000 ONLY. So we must align up
192 * initrd_start and keep initrd_end as is.
193 */
194 start = PAGE_ALIGN(start);
195 end = end & PAGE_MASK;
196
197 if (start < end)
198 printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);
199
200 for (; start < end; start += PAGE_SIZE) {
201 if (!virt_addr_valid(start))
202 continue;
203 free_reserved_page(virt_to_page(start));
204 }
205 }
206
207 /*
208 * This installs a clean page in the kernel's page table.
209 */
210 static struct page * __init
211 put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
212 {
213 pgd_t *pgd;
214 pud_t *pud;
215 pmd_t *pmd;
216 pte_t *pte;
217
218 pgd = pgd_offset_k(address); /* note: this is NOT pgd_offset()! */
219
220 {
221 pud = pud_alloc(&init_mm, pgd, address);
222 if (!pud)
223 goto out;
224 pmd = pmd_alloc(&init_mm, pud, address);
225 if (!pmd)
226 goto out;
227 pte = pte_alloc_kernel(pmd, address);
228 if (!pte)
229 goto out;
230 if (!pte_none(*pte))
231 goto out;
232 set_pte(pte, mk_pte(page, pgprot));
233 }
234 out:
235 /* no need for flush_tlb */
236 return page;
237 }
238
239 static void __init
240 setup_gate (void)
241 {
242 struct page *page;
243
244 /*
245 * Map the gate page twice: once read-only to export the ELF
246 * headers etc. and once execute-only page to enable
247 * privilege-promotion via "epc":
248 */
249 page = virt_to_page(ia64_imva(__start_gate_section));
250 put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
251 #ifdef HAVE_BUGGY_SEGREL
252 page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE));
253 put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
254 #else
255 put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
256 /* Fill in the holes (if any) with read-only zero pages: */
257 {
258 unsigned long addr;
259
260 for (addr = GATE_ADDR + PAGE_SIZE;
261 addr < GATE_ADDR + PERCPU_PAGE_SIZE;
262 addr += PAGE_SIZE)
263 {
264 put_kernel_page(ZERO_PAGE(0), addr,
265 PAGE_READONLY);
266 put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
267 PAGE_READONLY);
268 }
269 }
270 #endif
271 ia64_patch_gate();
272 }
273
274 static struct vm_area_struct gate_vma;
275
276 static int __init gate_vma_init(void)
277 {
278 gate_vma.vm_mm = NULL;
279 gate_vma.vm_start = FIXADDR_USER_START;
280 gate_vma.vm_end = FIXADDR_USER_END;
281 gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
282 gate_vma.vm_page_prot = __P101;
283
284 return 0;
285 }
286 __initcall(gate_vma_init);
287
288 struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
289 {
290 return &gate_vma;
291 }
292
293 int in_gate_area_no_mm(unsigned long addr)
294 {
295 if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
296 return 1;
297 return 0;
298 }
299
300 int in_gate_area(struct mm_struct *mm, unsigned long addr)
301 {
302 return in_gate_area_no_mm(addr);
303 }
304
305 void ia64_mmu_init(void *my_cpu_data)
306 {
307 unsigned long pta, impl_va_bits;
308 extern void tlb_init(void);
309
310 #ifdef CONFIG_DISABLE_VHPT
311 # define VHPT_ENABLE_BIT 0
312 #else
313 # define VHPT_ENABLE_BIT 1
314 #endif
315
316 /*
317 * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
318 * address space. The IA-64 architecture guarantees that at least 50 bits of
319 * virtual address space are implemented but if we pick a large enough page size
320 * (e.g., 64KB), the mapped address space is big enough that it will overlap with
321 * VMLPT. I assume that once we run on machines big enough to warrant 64KB pages,
322 * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
323 * problem in practice. Alternatively, we could truncate the top of the mapped
324 * address space to not permit mappings that would overlap with the VMLPT.
325 * --davidm 00/12/06
326 */
327 # define pte_bits 3
328 # define mapped_space_bits (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
329 /*
330 * The virtual page table has to cover the entire implemented address space within
331 * a region even though not all of this space may be mappable. The reason for
332 * this is that the Access bit and Dirty bit fault handlers perform
333 * non-speculative accesses to the virtual page table, so the address range of the
334 * virtual page table itself needs to be covered by virtual page table.
335 */
336 # define vmlpt_bits (impl_va_bits - PAGE_SHIFT + pte_bits)
337 # define POW2(n) (1ULL << (n))
338
339 impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));
340
341 if (impl_va_bits < 51 || impl_va_bits > 61)
342 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
343 /*
344 * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need,
345 * which must fit into "vmlpt_bits - pte_bits" slots. Second half of
346 * the test makes sure that our mapped space doesn't overlap the
347 * unimplemented hole in the middle of the region.
348 */
349 if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) ||
350 (mapped_space_bits > impl_va_bits - 1))
351 panic("Cannot build a big enough virtual-linear page table"
352 " to cover mapped address space.\n"
353 " Try using a smaller page size.\n");
354
355
356 /* place the VMLPT at the end of each page-table mapped region: */
357 pta = POW2(61) - POW2(vmlpt_bits);
358
359 /*
360 * Set the (virtually mapped linear) page table address. Bit
361 * 8 selects between the short and long format, bits 2-7 the
362 * size of the table, and bit 0 whether the VHPT walker is
363 * enabled.
364 */
365 ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);
366
367 ia64_tlb_init();
368
369 #ifdef CONFIG_HUGETLB_PAGE
370 ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2);
371 ia64_srlz_d();
372 #endif
373 }
374
375 #ifdef CONFIG_VIRTUAL_MEM_MAP
376 int vmemmap_find_next_valid_pfn(int node, int i)
377 {
378 unsigned long end_address, hole_next_pfn;
379 unsigned long stop_address;
380 pg_data_t *pgdat = NODE_DATA(node);
381
382 end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i];
383 end_address = PAGE_ALIGN(end_address);
384 stop_address = (unsigned long) &vmem_map[pgdat_end_pfn(pgdat)];
385
386 do {
387 pgd_t *pgd;
388 pud_t *pud;
389 pmd_t *pmd;
390 pte_t *pte;
391
392 pgd = pgd_offset_k(end_address);
393 if (pgd_none(*pgd)) {
394 end_address += PGDIR_SIZE;
395 continue;
396 }
397
398 pud = pud_offset(pgd, end_address);
399 if (pud_none(*pud)) {
400 end_address += PUD_SIZE;
401 continue;
402 }
403
404 pmd = pmd_offset(pud, end_address);
405 if (pmd_none(*pmd)) {
406 end_address += PMD_SIZE;
407 continue;
408 }
409
410 pte = pte_offset_kernel(pmd, end_address);
411 retry_pte:
412 if (pte_none(*pte)) {
413 end_address += PAGE_SIZE;
414 pte++;
415 if ((end_address < stop_address) &&
416 (end_address != ALIGN(end_address, 1UL << PMD_SHIFT)))
417 goto retry_pte;
418 continue;
419 }
420 /* Found next valid vmem_map page */
421 break;
422 } while (end_address < stop_address);
423
424 end_address = min(end_address, stop_address);
425 end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1;
426 hole_next_pfn = end_address / sizeof(struct page);
427 return hole_next_pfn - pgdat->node_start_pfn;
428 }
429
430 int __init create_mem_map_page_table(u64 start, u64 end, void *arg)
431 {
432 unsigned long address, start_page, end_page;
433 struct page *map_start, *map_end;
434 int node;
435 pgd_t *pgd;
436 pud_t *pud;
437 pmd_t *pmd;
438 pte_t *pte;
439
440 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
441 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT);
442
443 start_page = (unsigned long) map_start & PAGE_MASK;
444 end_page = PAGE_ALIGN((unsigned long) map_end);
445 node = paddr_to_nid(__pa(start));
446
447 for (address = start_page; address < end_page; address += PAGE_SIZE) {
448 pgd = pgd_offset_k(address);
449 if (pgd_none(*pgd))
450 pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
451 pud = pud_offset(pgd, address);
452
453 if (pud_none(*pud))
454 pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
455 pmd = pmd_offset(pud, address);
456
457 if (pmd_none(*pmd))
458 pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
459 pte = pte_offset_kernel(pmd, address);
460
461 if (pte_none(*pte))
462 set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT,
463 PAGE_KERNEL));
464 }
465 return 0;
466 }
467
468 struct memmap_init_callback_data {
469 struct page *start;
470 struct page *end;
471 int nid;
472 unsigned long zone;
473 };
474
475 static int __meminit
476 virtual_memmap_init(u64 start, u64 end, void *arg)
477 {
478 struct memmap_init_callback_data *args;
479 struct page *map_start, *map_end;
480
481 args = (struct memmap_init_callback_data *) arg;
482 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
483 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT);
484
485 if (map_start < args->start)
486 map_start = args->start;
487 if (map_end > args->end)
488 map_end = args->end;
489
490 /*
491 * We have to initialize "out of bounds" struct page elements that fit completely
492 * on the same pages that were allocated for the "in bounds" elements because they
493 * may be referenced later (and found to be "reserved").
494 */
495 map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page);
496 map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end)
497 / sizeof(struct page));
498
499 if (map_start < map_end)
500 memmap_init_zone((unsigned long)(map_end - map_start),
501 args->nid, args->zone, page_to_pfn(map_start),
502 MEMMAP_EARLY);
503 return 0;
504 }
505
506 void __meminit
507 memmap_init (unsigned long size, int nid, unsigned long zone,
508 unsigned long start_pfn)
509 {
510 if (!vmem_map)
511 memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY);
512 else {
513 struct page *start;
514 struct memmap_init_callback_data args;
515
516 start = pfn_to_page(start_pfn);
517 args.start = start;
518 args.end = start + size;
519 args.nid = nid;
520 args.zone = zone;
521
522 efi_memmap_walk(virtual_memmap_init, &args);
523 }
524 }
525
526 int
527 ia64_pfn_valid (unsigned long pfn)
528 {
529 char byte;
530 struct page *pg = pfn_to_page(pfn);
531
532 return (__get_user(byte, (char __user *) pg) == 0)
533 && ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK))
534 || (__get_user(byte, (char __user *) (pg + 1) - 1) == 0));
535 }
536 EXPORT_SYMBOL(ia64_pfn_valid);
537
538 int __init find_largest_hole(u64 start, u64 end, void *arg)
539 {
540 u64 *max_gap = arg;
541
542 static u64 last_end = PAGE_OFFSET;
543
544 /* NOTE: this algorithm assumes efi memmap table is ordered */
545
546 if (*max_gap < (start - last_end))
547 *max_gap = start - last_end;
548 last_end = end;
549 return 0;
550 }
551
552 #endif /* CONFIG_VIRTUAL_MEM_MAP */
553
554 int __init register_active_ranges(u64 start, u64 len, int nid)
555 {
556 u64 end = start + len;
557
558 #ifdef CONFIG_KEXEC
559 if (start > crashk_res.start && start < crashk_res.end)
560 start = crashk_res.end;
561 if (end > crashk_res.start && end < crashk_res.end)
562 end = crashk_res.start;
563 #endif
564
565 if (start < end)
566 memblock_add_node(__pa(start), end - start, nid);
567 return 0;
568 }
569
570 int
571 find_max_min_low_pfn (u64 start, u64 end, void *arg)
572 {
573 unsigned long pfn_start, pfn_end;
574 #ifdef CONFIG_FLATMEM
575 pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT;
576 pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT;
577 #else
578 pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT;
579 pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT;
580 #endif
581 min_low_pfn = min(min_low_pfn, pfn_start);
582 max_low_pfn = max(max_low_pfn, pfn_end);
583 return 0;
584 }
585
586 /*
587 * Boot command-line option "nolwsys" can be used to disable the use of any light-weight
588 * system call handler. When this option is in effect, all fsyscalls will end up bubbling
589 * down into the kernel and calling the normal (heavy-weight) syscall handler. This is
590 * useful for performance testing, but conceivably could also come in handy for debugging
591 * purposes.
592 */
593
594 static int nolwsys __initdata;
595
596 static int __init
597 nolwsys_setup (char *s)
598 {
599 nolwsys = 1;
600 return 1;
601 }
602
603 __setup("nolwsys", nolwsys_setup);
604
605 void __init
606 mem_init (void)
607 {
608 int i;
609
610 BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE);
611 BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE);
612 BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE);
613
614 #ifdef CONFIG_PCI
615 /*
616 * This needs to be called _after_ the command line has been parsed but _before_
617 * any drivers that may need the PCI DMA interface are initialized or bootmem has
618 * been freed.
619 */
620 platform_dma_init();
621 #endif
622
623 #ifdef CONFIG_FLATMEM
624 BUG_ON(!mem_map);
625 #endif
626
627 set_max_mapnr(max_low_pfn);
628 high_memory = __va(max_low_pfn * PAGE_SIZE);
629 free_all_bootmem();
630 mem_init_print_info(NULL);
631
632 /*
633 * For fsyscall entrpoints with no light-weight handler, use the ordinary
634 * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry
635 * code can tell them apart.
636 */
637 for (i = 0; i < NR_syscalls; ++i) {
638 extern unsigned long fsyscall_table[NR_syscalls];
639 extern unsigned long sys_call_table[NR_syscalls];
640
641 if (!fsyscall_table[i] || nolwsys)
642 fsyscall_table[i] = sys_call_table[i] | 1;
643 }
644 setup_gate();
645 }
646
647 #ifdef CONFIG_MEMORY_HOTPLUG
648 int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
649 {
650 pg_data_t *pgdat;
651 struct zone *zone;
652 unsigned long start_pfn = start >> PAGE_SHIFT;
653 unsigned long nr_pages = size >> PAGE_SHIFT;
654 int ret;
655
656 pgdat = NODE_DATA(nid);
657
658 zone = pgdat->node_zones +
659 zone_for_memory(nid, start, size, ZONE_NORMAL, for_device);
660 ret = __add_pages(nid, zone, start_pfn, nr_pages);
661
662 if (ret)
663 printk("%s: Problem encountered in __add_pages() as ret=%d\n",
664 __func__, ret);
665
666 return ret;
667 }
668
669 #ifdef CONFIG_MEMORY_HOTREMOVE
670 int arch_remove_memory(u64 start, u64 size)
671 {
672 unsigned long start_pfn = start >> PAGE_SHIFT;
673 unsigned long nr_pages = size >> PAGE_SHIFT;
674 struct zone *zone;
675 int ret;
676
677 zone = page_zone(pfn_to_page(start_pfn));
678 ret = __remove_pages(zone, start_pfn, nr_pages);
679 if (ret)
680 pr_warn("%s: Problem encountered in __remove_pages() as"
681 " ret=%d\n", __func__, ret);
682
683 return ret;
684 }
685 #endif
686 #endif
687
688 /**
689 * show_mem - give short summary of memory stats
690 *
691 * Shows a simple page count of reserved and used pages in the system.
692 * For discontig machines, it does this on a per-pgdat basis.
693 */
694 void show_mem(unsigned int filter)
695 {
696 int total_reserved = 0;
697 unsigned long total_present = 0;
698 pg_data_t *pgdat;
699
700 printk(KERN_INFO "Mem-info:\n");
701 show_free_areas(filter);
702 printk(KERN_INFO "Node memory in pages:\n");
703 for_each_online_pgdat(pgdat) {
704 unsigned long present;
705 unsigned long flags;
706 int reserved = 0;
707 int nid = pgdat->node_id;
708 int zoneid;
709
710 if (skip_free_areas_node(filter, nid))
711 continue;
712 pgdat_resize_lock(pgdat, &flags);
713
714 for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
715 struct zone *zone = &pgdat->node_zones[zoneid];
716 if (!populated_zone(zone))
717 continue;
718
719 reserved += zone->present_pages - zone->managed_pages;
720 }
721 present = pgdat->node_present_pages;
722
723 pgdat_resize_unlock(pgdat, &flags);
724 total_present += present;
725 total_reserved += reserved;
726 printk(KERN_INFO "Node %4d: RAM: %11ld, rsvd: %8d, ",
727 nid, present, reserved);
728 }
729 printk(KERN_INFO "%ld pages of RAM\n", total_present);
730 printk(KERN_INFO "%d reserved pages\n", total_reserved);
731 printk(KERN_INFO "Total of %ld pages in page table cache\n",
732 quicklist_total_size());
733 printk(KERN_INFO "%ld free buffer pages\n", nr_free_buffer_pages());
734 }