[PATCH] Drop nr_free_pages_pgdat()
[sfrench/cifs-2.6.git] / arch / ia64 / mm / init.c
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/mm.h>
14 #include <linux/mmzone.h>
15 #include <linux/module.h>
16 #include <linux/personality.h>
17 #include <linux/reboot.h>
18 #include <linux/slab.h>
19 #include <linux/swap.h>
20 #include <linux/proc_fs.h>
21 #include <linux/bitops.h>
22 #include <linux/kexec.h>
23
24 #include <asm/a.out.h>
25 #include <asm/dma.h>
26 #include <asm/ia32.h>
27 #include <asm/io.h>
28 #include <asm/machvec.h>
29 #include <asm/numa.h>
30 #include <asm/patch.h>
31 #include <asm/pgalloc.h>
32 #include <asm/sal.h>
33 #include <asm/sections.h>
34 #include <asm/system.h>
35 #include <asm/tlb.h>
36 #include <asm/uaccess.h>
37 #include <asm/unistd.h>
38 #include <asm/mca.h>
39
40 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
41
42 DEFINE_PER_CPU(unsigned long *, __pgtable_quicklist);
43 DEFINE_PER_CPU(long, __pgtable_quicklist_size);
44
45 extern void ia64_tlb_init (void);
46
47 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;
48
49 #ifdef CONFIG_VIRTUAL_MEM_MAP
50 unsigned long vmalloc_end = VMALLOC_END_INIT;
51 EXPORT_SYMBOL(vmalloc_end);
52 struct page *vmem_map;
53 EXPORT_SYMBOL(vmem_map);
54 #endif
55
56 struct page *zero_page_memmap_ptr;      /* map entry for zero page */
57 EXPORT_SYMBOL(zero_page_memmap_ptr);
58
59 #define MIN_PGT_PAGES                   25UL
60 #define MAX_PGT_FREES_PER_PASS          16L
61 #define PGT_FRACTION_OF_NODE_MEM        16
62
63 static inline long
64 max_pgt_pages(void)
65 {
66         u64 node_free_pages, max_pgt_pages;
67
68 #ifndef CONFIG_NUMA
69         node_free_pages = nr_free_pages();
70 #else
71         node_free_pages = node_page_state(numa_node_id(), NR_FREE_PAGES);
72 #endif
73         max_pgt_pages = node_free_pages / PGT_FRACTION_OF_NODE_MEM;
74         max_pgt_pages = max(max_pgt_pages, MIN_PGT_PAGES);
75         return max_pgt_pages;
76 }
77
78 static inline long
79 min_pages_to_free(void)
80 {
81         long pages_to_free;
82
83         pages_to_free = pgtable_quicklist_size - max_pgt_pages();
84         pages_to_free = min(pages_to_free, MAX_PGT_FREES_PER_PASS);
85         return pages_to_free;
86 }
87
88 void
89 check_pgt_cache(void)
90 {
91         long pages_to_free;
92
93         if (unlikely(pgtable_quicklist_size <= MIN_PGT_PAGES))
94                 return;
95
96         preempt_disable();
97         while (unlikely((pages_to_free = min_pages_to_free()) > 0)) {
98                 while (pages_to_free--) {
99                         free_page((unsigned long)pgtable_quicklist_alloc());
100                 }
101                 preempt_enable();
102                 preempt_disable();
103         }
104         preempt_enable();
105 }
106
107 void
108 lazy_mmu_prot_update (pte_t pte)
109 {
110         unsigned long addr;
111         struct page *page;
112         unsigned long order;
113
114         if (!pte_exec(pte))
115                 return;                         /* not an executable page... */
116
117         page = pte_page(pte);
118         addr = (unsigned long) page_address(page);
119
120         if (test_bit(PG_arch_1, &page->flags))
121                 return;                         /* i-cache is already coherent with d-cache */
122
123         if (PageCompound(page)) {
124                 order = (unsigned long) (page[1].lru.prev);
125                 flush_icache_range(addr, addr + (1UL << order << PAGE_SHIFT));
126         }
127         else
128                 flush_icache_range(addr, addr + PAGE_SIZE);
129         set_bit(PG_arch_1, &page->flags);       /* mark page as clean */
130 }
131
132 /*
133  * Since DMA is i-cache coherent, any (complete) pages that were written via
134  * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
135  * flush them when they get mapped into an executable vm-area.
136  */
137 void
138 dma_mark_clean(void *addr, size_t size)
139 {
140         unsigned long pg_addr, end;
141
142         pg_addr = PAGE_ALIGN((unsigned long) addr);
143         end = (unsigned long) addr + size;
144         while (pg_addr + PAGE_SIZE <= end) {
145                 struct page *page = virt_to_page(pg_addr);
146                 set_bit(PG_arch_1, &page->flags);
147                 pg_addr += PAGE_SIZE;
148         }
149 }
150
151 inline void
152 ia64_set_rbs_bot (void)
153 {
154         unsigned long stack_size = current->signal->rlim[RLIMIT_STACK].rlim_max & -16;
155
156         if (stack_size > MAX_USER_STACK_SIZE)
157                 stack_size = MAX_USER_STACK_SIZE;
158         current->thread.rbs_bot = STACK_TOP - stack_size;
159 }
160
161 /*
162  * This performs some platform-dependent address space initialization.
163  * On IA-64, we want to setup the VM area for the register backing
164  * store (which grows upwards) and install the gateway page which is
165  * used for signal trampolines, etc.
166  */
167 void
168 ia64_init_addr_space (void)
169 {
170         struct vm_area_struct *vma;
171
172         ia64_set_rbs_bot();
173
174         /*
175          * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
176          * the problem.  When the process attempts to write to the register backing store
177          * for the first time, it will get a SEGFAULT in this case.
178          */
179         vma = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
180         if (vma) {
181                 memset(vma, 0, sizeof(*vma));
182                 vma->vm_mm = current->mm;
183                 vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
184                 vma->vm_end = vma->vm_start + PAGE_SIZE;
185                 vma->vm_page_prot = protection_map[VM_DATA_DEFAULT_FLAGS & 0x7];
186                 vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT;
187                 down_write(&current->mm->mmap_sem);
188                 if (insert_vm_struct(current->mm, vma)) {
189                         up_write(&current->mm->mmap_sem);
190                         kmem_cache_free(vm_area_cachep, vma);
191                         return;
192                 }
193                 up_write(&current->mm->mmap_sem);
194         }
195
196         /* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
197         if (!(current->personality & MMAP_PAGE_ZERO)) {
198                 vma = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
199                 if (vma) {
200                         memset(vma, 0, sizeof(*vma));
201                         vma->vm_mm = current->mm;
202                         vma->vm_end = PAGE_SIZE;
203                         vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
204                         vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO | VM_RESERVED;
205                         down_write(&current->mm->mmap_sem);
206                         if (insert_vm_struct(current->mm, vma)) {
207                                 up_write(&current->mm->mmap_sem);
208                                 kmem_cache_free(vm_area_cachep, vma);
209                                 return;
210                         }
211                         up_write(&current->mm->mmap_sem);
212                 }
213         }
214 }
215
216 void
217 free_initmem (void)
218 {
219         unsigned long addr, eaddr;
220
221         addr = (unsigned long) ia64_imva(__init_begin);
222         eaddr = (unsigned long) ia64_imva(__init_end);
223         while (addr < eaddr) {
224                 ClearPageReserved(virt_to_page(addr));
225                 init_page_count(virt_to_page(addr));
226                 free_page(addr);
227                 ++totalram_pages;
228                 addr += PAGE_SIZE;
229         }
230         printk(KERN_INFO "Freeing unused kernel memory: %ldkB freed\n",
231                (__init_end - __init_begin) >> 10);
232 }
233
234 void __init
235 free_initrd_mem (unsigned long start, unsigned long end)
236 {
237         struct page *page;
238         /*
239          * EFI uses 4KB pages while the kernel can use 4KB or bigger.
240          * Thus EFI and the kernel may have different page sizes. It is
241          * therefore possible to have the initrd share the same page as
242          * the end of the kernel (given current setup).
243          *
244          * To avoid freeing/using the wrong page (kernel sized) we:
245          *      - align up the beginning of initrd
246          *      - align down the end of initrd
247          *
248          *  |             |
249          *  |=============| a000
250          *  |             |
251          *  |             |
252          *  |             | 9000
253          *  |/////////////|
254          *  |/////////////|
255          *  |=============| 8000
256          *  |///INITRD////|
257          *  |/////////////|
258          *  |/////////////| 7000
259          *  |             |
260          *  |KKKKKKKKKKKKK|
261          *  |=============| 6000
262          *  |KKKKKKKKKKKKK|
263          *  |KKKKKKKKKKKKK|
264          *  K=kernel using 8KB pages
265          *
266          * In this example, we must free page 8000 ONLY. So we must align up
267          * initrd_start and keep initrd_end as is.
268          */
269         start = PAGE_ALIGN(start);
270         end = end & PAGE_MASK;
271
272         if (start < end)
273                 printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);
274
275         for (; start < end; start += PAGE_SIZE) {
276                 if (!virt_addr_valid(start))
277                         continue;
278                 page = virt_to_page(start);
279                 ClearPageReserved(page);
280                 init_page_count(page);
281                 free_page(start);
282                 ++totalram_pages;
283         }
284 }
285
286 /*
287  * This installs a clean page in the kernel's page table.
288  */
289 static struct page * __init
290 put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
291 {
292         pgd_t *pgd;
293         pud_t *pud;
294         pmd_t *pmd;
295         pte_t *pte;
296
297         if (!PageReserved(page))
298                 printk(KERN_ERR "put_kernel_page: page at 0x%p not in reserved memory\n",
299                        page_address(page));
300
301         pgd = pgd_offset_k(address);            /* note: this is NOT pgd_offset()! */
302
303         {
304                 pud = pud_alloc(&init_mm, pgd, address);
305                 if (!pud)
306                         goto out;
307                 pmd = pmd_alloc(&init_mm, pud, address);
308                 if (!pmd)
309                         goto out;
310                 pte = pte_alloc_kernel(pmd, address);
311                 if (!pte)
312                         goto out;
313                 if (!pte_none(*pte))
314                         goto out;
315                 set_pte(pte, mk_pte(page, pgprot));
316         }
317   out:
318         /* no need for flush_tlb */
319         return page;
320 }
321
322 static void __init
323 setup_gate (void)
324 {
325         struct page *page;
326
327         /*
328          * Map the gate page twice: once read-only to export the ELF
329          * headers etc. and once execute-only page to enable
330          * privilege-promotion via "epc":
331          */
332         page = virt_to_page(ia64_imva(__start_gate_section));
333         put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
334 #ifdef HAVE_BUGGY_SEGREL
335         page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE));
336         put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
337 #else
338         put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
339         /* Fill in the holes (if any) with read-only zero pages: */
340         {
341                 unsigned long addr;
342
343                 for (addr = GATE_ADDR + PAGE_SIZE;
344                      addr < GATE_ADDR + PERCPU_PAGE_SIZE;
345                      addr += PAGE_SIZE)
346                 {
347                         put_kernel_page(ZERO_PAGE(0), addr,
348                                         PAGE_READONLY);
349                         put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
350                                         PAGE_READONLY);
351                 }
352         }
353 #endif
354         ia64_patch_gate();
355 }
356
357 void __devinit
358 ia64_mmu_init (void *my_cpu_data)
359 {
360         unsigned long psr, pta, impl_va_bits;
361         extern void __devinit tlb_init (void);
362
363 #ifdef CONFIG_DISABLE_VHPT
364 #       define VHPT_ENABLE_BIT  0
365 #else
366 #       define VHPT_ENABLE_BIT  1
367 #endif
368
369         /* Pin mapping for percpu area into TLB */
370         psr = ia64_clear_ic();
371         ia64_itr(0x2, IA64_TR_PERCPU_DATA, PERCPU_ADDR,
372                  pte_val(pfn_pte(__pa(my_cpu_data) >> PAGE_SHIFT, PAGE_KERNEL)),
373                  PERCPU_PAGE_SHIFT);
374
375         ia64_set_psr(psr);
376         ia64_srlz_i();
377
378         /*
379          * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
380          * address space.  The IA-64 architecture guarantees that at least 50 bits of
381          * virtual address space are implemented but if we pick a large enough page size
382          * (e.g., 64KB), the mapped address space is big enough that it will overlap with
383          * VMLPT.  I assume that once we run on machines big enough to warrant 64KB pages,
384          * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
385          * problem in practice.  Alternatively, we could truncate the top of the mapped
386          * address space to not permit mappings that would overlap with the VMLPT.
387          * --davidm 00/12/06
388          */
389 #       define pte_bits                 3
390 #       define mapped_space_bits        (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
391         /*
392          * The virtual page table has to cover the entire implemented address space within
393          * a region even though not all of this space may be mappable.  The reason for
394          * this is that the Access bit and Dirty bit fault handlers perform
395          * non-speculative accesses to the virtual page table, so the address range of the
396          * virtual page table itself needs to be covered by virtual page table.
397          */
398 #       define vmlpt_bits               (impl_va_bits - PAGE_SHIFT + pte_bits)
399 #       define POW2(n)                  (1ULL << (n))
400
401         impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));
402
403         if (impl_va_bits < 51 || impl_va_bits > 61)
404                 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
405         /*
406          * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need,
407          * which must fit into "vmlpt_bits - pte_bits" slots. Second half of
408          * the test makes sure that our mapped space doesn't overlap the
409          * unimplemented hole in the middle of the region.
410          */
411         if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) ||
412             (mapped_space_bits > impl_va_bits - 1))
413                 panic("Cannot build a big enough virtual-linear page table"
414                       " to cover mapped address space.\n"
415                       " Try using a smaller page size.\n");
416
417
418         /* place the VMLPT at the end of each page-table mapped region: */
419         pta = POW2(61) - POW2(vmlpt_bits);
420
421         /*
422          * Set the (virtually mapped linear) page table address.  Bit
423          * 8 selects between the short and long format, bits 2-7 the
424          * size of the table, and bit 0 whether the VHPT walker is
425          * enabled.
426          */
427         ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);
428
429         ia64_tlb_init();
430
431 #ifdef  CONFIG_HUGETLB_PAGE
432         ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2);
433         ia64_srlz_d();
434 #endif
435 }
436
437 #ifdef CONFIG_VIRTUAL_MEM_MAP
438 int vmemmap_find_next_valid_pfn(int node, int i)
439 {
440         unsigned long end_address, hole_next_pfn;
441         unsigned long stop_address;
442         pg_data_t *pgdat = NODE_DATA(node);
443
444         end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i];
445         end_address = PAGE_ALIGN(end_address);
446
447         stop_address = (unsigned long) &vmem_map[
448                 pgdat->node_start_pfn + pgdat->node_spanned_pages];
449
450         do {
451                 pgd_t *pgd;
452                 pud_t *pud;
453                 pmd_t *pmd;
454                 pte_t *pte;
455
456                 pgd = pgd_offset_k(end_address);
457                 if (pgd_none(*pgd)) {
458                         end_address += PGDIR_SIZE;
459                         continue;
460                 }
461
462                 pud = pud_offset(pgd, end_address);
463                 if (pud_none(*pud)) {
464                         end_address += PUD_SIZE;
465                         continue;
466                 }
467
468                 pmd = pmd_offset(pud, end_address);
469                 if (pmd_none(*pmd)) {
470                         end_address += PMD_SIZE;
471                         continue;
472                 }
473
474                 pte = pte_offset_kernel(pmd, end_address);
475 retry_pte:
476                 if (pte_none(*pte)) {
477                         end_address += PAGE_SIZE;
478                         pte++;
479                         if ((end_address < stop_address) &&
480                             (end_address != ALIGN(end_address, 1UL << PMD_SHIFT)))
481                                 goto retry_pte;
482                         continue;
483                 }
484                 /* Found next valid vmem_map page */
485                 break;
486         } while (end_address < stop_address);
487
488         end_address = min(end_address, stop_address);
489         end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1;
490         hole_next_pfn = end_address / sizeof(struct page);
491         return hole_next_pfn - pgdat->node_start_pfn;
492 }
493
494 int __init
495 create_mem_map_page_table (u64 start, u64 end, void *arg)
496 {
497         unsigned long address, start_page, end_page;
498         struct page *map_start, *map_end;
499         int node;
500         pgd_t *pgd;
501         pud_t *pud;
502         pmd_t *pmd;
503         pte_t *pte;
504
505         map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
506         map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
507
508         start_page = (unsigned long) map_start & PAGE_MASK;
509         end_page = PAGE_ALIGN((unsigned long) map_end);
510         node = paddr_to_nid(__pa(start));
511
512         for (address = start_page; address < end_page; address += PAGE_SIZE) {
513                 pgd = pgd_offset_k(address);
514                 if (pgd_none(*pgd))
515                         pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
516                 pud = pud_offset(pgd, address);
517
518                 if (pud_none(*pud))
519                         pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
520                 pmd = pmd_offset(pud, address);
521
522                 if (pmd_none(*pmd))
523                         pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
524                 pte = pte_offset_kernel(pmd, address);
525
526                 if (pte_none(*pte))
527                         set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT,
528                                              PAGE_KERNEL));
529         }
530         return 0;
531 }
532
533 struct memmap_init_callback_data {
534         struct page *start;
535         struct page *end;
536         int nid;
537         unsigned long zone;
538 };
539
540 static int
541 virtual_memmap_init (u64 start, u64 end, void *arg)
542 {
543         struct memmap_init_callback_data *args;
544         struct page *map_start, *map_end;
545
546         args = (struct memmap_init_callback_data *) arg;
547         map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
548         map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
549
550         if (map_start < args->start)
551                 map_start = args->start;
552         if (map_end > args->end)
553                 map_end = args->end;
554
555         /*
556          * We have to initialize "out of bounds" struct page elements that fit completely
557          * on the same pages that were allocated for the "in bounds" elements because they
558          * may be referenced later (and found to be "reserved").
559          */
560         map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page);
561         map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end)
562                     / sizeof(struct page));
563
564         if (map_start < map_end)
565                 memmap_init_zone((unsigned long)(map_end - map_start),
566                                  args->nid, args->zone, page_to_pfn(map_start),
567                                  MEMMAP_EARLY);
568         return 0;
569 }
570
571 void
572 memmap_init (unsigned long size, int nid, unsigned long zone,
573              unsigned long start_pfn)
574 {
575         if (!vmem_map)
576                 memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY);
577         else {
578                 struct page *start;
579                 struct memmap_init_callback_data args;
580
581                 start = pfn_to_page(start_pfn);
582                 args.start = start;
583                 args.end = start + size;
584                 args.nid = nid;
585                 args.zone = zone;
586
587                 efi_memmap_walk(virtual_memmap_init, &args);
588         }
589 }
590
591 int
592 ia64_pfn_valid (unsigned long pfn)
593 {
594         char byte;
595         struct page *pg = pfn_to_page(pfn);
596
597         return     (__get_user(byte, (char __user *) pg) == 0)
598                 && ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK))
599                         || (__get_user(byte, (char __user *) (pg + 1) - 1) == 0));
600 }
601 EXPORT_SYMBOL(ia64_pfn_valid);
602
603 int __init
604 find_largest_hole (u64 start, u64 end, void *arg)
605 {
606         u64 *max_gap = arg;
607
608         static u64 last_end = PAGE_OFFSET;
609
610         /* NOTE: this algorithm assumes efi memmap table is ordered */
611
612         if (*max_gap < (start - last_end))
613                 *max_gap = start - last_end;
614         last_end = end;
615         return 0;
616 }
617
618 #endif /* CONFIG_VIRTUAL_MEM_MAP */
619
620 int __init
621 register_active_ranges(u64 start, u64 end, void *arg)
622 {
623         int nid = paddr_to_nid(__pa(start));
624
625         if (nid < 0)
626                 nid = 0;
627 #ifdef CONFIG_KEXEC
628         if (start > crashk_res.start && start < crashk_res.end)
629                 start = crashk_res.end;
630         if (end > crashk_res.start && end < crashk_res.end)
631                 end = crashk_res.start;
632 #endif
633
634         if (start < end)
635                 add_active_range(nid, __pa(start) >> PAGE_SHIFT,
636                         __pa(end) >> PAGE_SHIFT);
637         return 0;
638 }
639
640 static int __init
641 count_reserved_pages (u64 start, u64 end, void *arg)
642 {
643         unsigned long num_reserved = 0;
644         unsigned long *count = arg;
645
646         for (; start < end; start += PAGE_SIZE)
647                 if (PageReserved(virt_to_page(start)))
648                         ++num_reserved;
649         *count += num_reserved;
650         return 0;
651 }
652
653 /*
654  * Boot command-line option "nolwsys" can be used to disable the use of any light-weight
655  * system call handler.  When this option is in effect, all fsyscalls will end up bubbling
656  * down into the kernel and calling the normal (heavy-weight) syscall handler.  This is
657  * useful for performance testing, but conceivably could also come in handy for debugging
658  * purposes.
659  */
660
661 static int nolwsys __initdata;
662
663 static int __init
664 nolwsys_setup (char *s)
665 {
666         nolwsys = 1;
667         return 1;
668 }
669
670 __setup("nolwsys", nolwsys_setup);
671
672 void __init
673 mem_init (void)
674 {
675         long reserved_pages, codesize, datasize, initsize;
676         pg_data_t *pgdat;
677         int i;
678         static struct kcore_list kcore_mem, kcore_vmem, kcore_kernel;
679
680         BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE);
681         BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE);
682         BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE);
683
684 #ifdef CONFIG_PCI
685         /*
686          * This needs to be called _after_ the command line has been parsed but _before_
687          * any drivers that may need the PCI DMA interface are initialized or bootmem has
688          * been freed.
689          */
690         platform_dma_init();
691 #endif
692
693 #ifdef CONFIG_FLATMEM
694         if (!mem_map)
695                 BUG();
696         max_mapnr = max_low_pfn;
697 #endif
698
699         high_memory = __va(max_low_pfn * PAGE_SIZE);
700
701         kclist_add(&kcore_mem, __va(0), max_low_pfn * PAGE_SIZE);
702         kclist_add(&kcore_vmem, (void *)VMALLOC_START, VMALLOC_END-VMALLOC_START);
703         kclist_add(&kcore_kernel, _stext, _end - _stext);
704
705         for_each_online_pgdat(pgdat)
706                 if (pgdat->bdata->node_bootmem_map)
707                         totalram_pages += free_all_bootmem_node(pgdat);
708
709         reserved_pages = 0;
710         efi_memmap_walk(count_reserved_pages, &reserved_pages);
711
712         codesize =  (unsigned long) _etext - (unsigned long) _stext;
713         datasize =  (unsigned long) _edata - (unsigned long) _etext;
714         initsize =  (unsigned long) __init_end - (unsigned long) __init_begin;
715
716         printk(KERN_INFO "Memory: %luk/%luk available (%luk code, %luk reserved, "
717                "%luk data, %luk init)\n", (unsigned long) nr_free_pages() << (PAGE_SHIFT - 10),
718                num_physpages << (PAGE_SHIFT - 10), codesize >> 10,
719                reserved_pages << (PAGE_SHIFT - 10), datasize >> 10, initsize >> 10);
720
721
722         /*
723          * For fsyscall entrpoints with no light-weight handler, use the ordinary
724          * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry
725          * code can tell them apart.
726          */
727         for (i = 0; i < NR_syscalls; ++i) {
728                 extern unsigned long fsyscall_table[NR_syscalls];
729                 extern unsigned long sys_call_table[NR_syscalls];
730
731                 if (!fsyscall_table[i] || nolwsys)
732                         fsyscall_table[i] = sys_call_table[i] | 1;
733         }
734         setup_gate();
735
736 #ifdef CONFIG_IA32_SUPPORT
737         ia32_mem_init();
738 #endif
739 }
740
741 #ifdef CONFIG_MEMORY_HOTPLUG
742 void online_page(struct page *page)
743 {
744         ClearPageReserved(page);
745         init_page_count(page);
746         __free_page(page);
747         totalram_pages++;
748         num_physpages++;
749 }
750
751 int arch_add_memory(int nid, u64 start, u64 size)
752 {
753         pg_data_t *pgdat;
754         struct zone *zone;
755         unsigned long start_pfn = start >> PAGE_SHIFT;
756         unsigned long nr_pages = size >> PAGE_SHIFT;
757         int ret;
758
759         pgdat = NODE_DATA(nid);
760
761         zone = pgdat->node_zones + ZONE_NORMAL;
762         ret = __add_pages(zone, start_pfn, nr_pages);
763
764         if (ret)
765                 printk("%s: Problem encountered in __add_pages() as ret=%d\n",
766                        __FUNCTION__,  ret);
767
768         return ret;
769 }
770
771 int remove_memory(u64 start, u64 size)
772 {
773         return -EINVAL;
774 }
775 EXPORT_SYMBOL_GPL(remove_memory);
776 #endif