3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
6 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
7 * Copyright (C) 1996 Paul Mackerras
8 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
10 * Derived from "arch/i386/mm/init.c"
11 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
20 #include <linux/module.h>
21 #include <linux/sched.h>
22 #include <linux/kernel.h>
23 #include <linux/errno.h>
24 #include <linux/string.h>
25 #include <linux/types.h>
27 #include <linux/stddef.h>
28 #include <linux/init.h>
29 #include <linux/bootmem.h>
30 #include <linux/highmem.h>
31 #include <linux/initrd.h>
32 #include <linux/pagemap.h>
33 #include <linux/suspend.h>
34 #include <linux/lmb.h>
36 #include <asm/pgalloc.h>
39 #include <asm/mmu_context.h>
40 #include <asm/pgtable.h>
43 #include <asm/machdep.h>
44 #include <asm/btext.h>
46 #include <asm/sections.h>
48 #include <asm/fixmap.h>
52 #ifndef CPU_FTR_COHERENT_ICACHE
53 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
54 #define CPU_FTR_NOEXECUTE 0
57 int init_bootmem_done;
59 unsigned long memory_limit;
65 EXPORT_SYMBOL(kmap_prot);
66 EXPORT_SYMBOL(kmap_pte);
68 static inline pte_t *virt_to_kpte(unsigned long vaddr)
70 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
71 vaddr), vaddr), vaddr);
75 int page_is_ram(unsigned long pfn)
77 unsigned long paddr = (pfn << PAGE_SHIFT);
79 #ifndef CONFIG_PPC64 /* XXX for now */
80 return paddr < __pa(high_memory);
83 for (i=0; i < lmb.memory.cnt; i++) {
86 base = lmb.memory.region[i].base;
88 if ((paddr >= base) &&
89 (paddr < (base + lmb.memory.region[i].size))) {
98 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
99 unsigned long size, pgprot_t vma_prot)
101 if (ppc_md.phys_mem_access_prot)
102 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
104 if (!page_is_ram(pfn))
105 vma_prot = __pgprot(pgprot_val(vma_prot)
106 | _PAGE_GUARDED | _PAGE_NO_CACHE);
109 EXPORT_SYMBOL(phys_mem_access_prot);
111 #ifdef CONFIG_MEMORY_HOTPLUG
114 int memory_add_physaddr_to_nid(u64 start)
116 return hot_add_scn_to_nid(start);
120 int arch_add_memory(int nid, u64 start, u64 size)
122 struct pglist_data *pgdata;
124 unsigned long start_pfn = start >> PAGE_SHIFT;
125 unsigned long nr_pages = size >> PAGE_SHIFT;
127 pgdata = NODE_DATA(nid);
129 start = (unsigned long)__va(start);
130 create_section_mapping(start, start + size);
132 /* this should work for most non-highmem platforms */
133 zone = pgdata->node_zones;
135 return __add_pages(zone, start_pfn, nr_pages);
138 #ifdef CONFIG_MEMORY_HOTREMOVE
139 int remove_memory(u64 start, u64 size)
141 unsigned long start_pfn, end_pfn;
144 start_pfn = start >> PAGE_SHIFT;
145 end_pfn = start_pfn + (size >> PAGE_SHIFT);
146 ret = offline_pages(start_pfn, end_pfn, 120 * HZ);
149 /* Arch-specific calls go here - next patch */
153 #endif /* CONFIG_MEMORY_HOTREMOVE */
156 * walk_memory_resource() needs to make sure there is no holes in a given
157 * memory range. On PPC64, since this range comes from /sysfs, the range
158 * is guaranteed to be valid, non-overlapping and can not contain any
159 * holes. By the time we get here (memory add or remove), /proc/device-tree
160 * is updated and correct. Only reason we need to check against device-tree
161 * would be if we allow user-land to specify a memory range through a
162 * system call/ioctl etc. instead of doing offline/online through /sysfs.
165 walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
166 int (*func)(unsigned long, unsigned long, void *))
168 return (*func)(start_pfn, nr_pages, arg);
171 #endif /* CONFIG_MEMORY_HOTPLUG */
175 unsigned long total = 0, reserved = 0;
176 unsigned long shared = 0, cached = 0;
177 unsigned long highmem = 0;
182 printk("Mem-info:\n");
184 for_each_online_pgdat(pgdat) {
186 pgdat_resize_lock(pgdat, &flags);
187 for (i = 0; i < pgdat->node_spanned_pages; i++) {
188 if (!pfn_valid(pgdat->node_start_pfn + i))
190 page = pgdat_page_nr(pgdat, i);
192 if (PageHighMem(page))
194 if (PageReserved(page))
196 else if (PageSwapCache(page))
198 else if (page_count(page))
199 shared += page_count(page) - 1;
201 pgdat_resize_unlock(pgdat, &flags);
203 printk("%ld pages of RAM\n", total);
204 #ifdef CONFIG_HIGHMEM
205 printk("%ld pages of HIGHMEM\n", highmem);
207 printk("%ld reserved pages\n", reserved);
208 printk("%ld pages shared\n", shared);
209 printk("%ld pages swap cached\n", cached);
213 * Initialize the bootmem system and give it all the memory we
214 * have available. If we are using highmem, we only put the
215 * lowmem into the bootmem system.
217 #ifndef CONFIG_NEED_MULTIPLE_NODES
218 void __init do_init_bootmem(void)
221 unsigned long start, bootmap_pages;
222 unsigned long total_pages;
225 max_low_pfn = max_pfn = lmb_end_of_DRAM() >> PAGE_SHIFT;
226 total_pages = (lmb_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT;
227 #ifdef CONFIG_HIGHMEM
228 total_pages = total_lowmem >> PAGE_SHIFT;
229 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
233 * Find an area to use for the bootmem bitmap. Calculate the size of
234 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE.
235 * Add 1 additional page in case the address isn't page-aligned.
237 bootmap_pages = bootmem_bootmap_pages(total_pages);
239 start = lmb_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE);
241 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
242 boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn);
244 /* Add active regions with valid PFNs */
245 for (i = 0; i < lmb.memory.cnt; i++) {
246 unsigned long start_pfn, end_pfn;
247 start_pfn = lmb.memory.region[i].base >> PAGE_SHIFT;
248 end_pfn = start_pfn + lmb_size_pages(&lmb.memory, i);
249 add_active_range(0, start_pfn, end_pfn);
252 /* Add all physical memory to the bootmem map, mark each area
255 #ifdef CONFIG_HIGHMEM
256 free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT);
258 /* reserve the sections we're already using */
259 for (i = 0; i < lmb.reserved.cnt; i++) {
260 unsigned long addr = lmb.reserved.region[i].base +
261 lmb_size_bytes(&lmb.reserved, i) - 1;
262 if (addr < lowmem_end_addr)
263 reserve_bootmem(lmb.reserved.region[i].base,
264 lmb_size_bytes(&lmb.reserved, i),
266 else if (lmb.reserved.region[i].base < lowmem_end_addr) {
267 unsigned long adjusted_size = lowmem_end_addr -
268 lmb.reserved.region[i].base;
269 reserve_bootmem(lmb.reserved.region[i].base,
270 adjusted_size, BOOTMEM_DEFAULT);
274 free_bootmem_with_active_regions(0, max_pfn);
276 /* reserve the sections we're already using */
277 for (i = 0; i < lmb.reserved.cnt; i++)
278 reserve_bootmem(lmb.reserved.region[i].base,
279 lmb_size_bytes(&lmb.reserved, i),
283 /* XXX need to clip this if using highmem? */
284 sparse_memory_present_with_active_regions(0);
286 init_bootmem_done = 1;
289 /* mark pages that don't exist as nosave */
290 static int __init mark_nonram_nosave(void)
292 unsigned long lmb_next_region_start_pfn,
296 for (i = 0; i < lmb.memory.cnt - 1; i++) {
298 (lmb.memory.region[i].base >> PAGE_SHIFT) +
299 (lmb.memory.region[i].size >> PAGE_SHIFT);
300 lmb_next_region_start_pfn =
301 lmb.memory.region[i+1].base >> PAGE_SHIFT;
303 if (lmb_region_max_pfn < lmb_next_region_start_pfn)
304 register_nosave_region(lmb_region_max_pfn,
305 lmb_next_region_start_pfn);
312 * paging_init() sets up the page tables - in fact we've already done this.
314 void __init paging_init(void)
316 unsigned long total_ram = lmb_phys_mem_size();
317 unsigned long top_of_ram = lmb_end_of_DRAM();
318 unsigned long max_zone_pfns[MAX_NR_ZONES];
321 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
322 unsigned long end = __fix_to_virt(FIX_HOLE);
324 for (; v < end; v += PAGE_SIZE)
325 map_page(v, 0, 0); /* XXX gross */
328 #ifdef CONFIG_HIGHMEM
329 map_page(PKMAP_BASE, 0, 0); /* XXX gross */
330 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
332 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
333 kmap_prot = PAGE_KERNEL;
334 #endif /* CONFIG_HIGHMEM */
336 printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
337 top_of_ram, total_ram);
338 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
339 (top_of_ram - total_ram) >> 20);
340 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
341 #ifdef CONFIG_HIGHMEM
342 max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
343 max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT;
345 max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
347 free_area_init_nodes(max_zone_pfns);
349 mark_nonram_nosave();
351 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */
353 void __init mem_init(void)
355 #ifdef CONFIG_NEED_MULTIPLE_NODES
361 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;
363 num_physpages = lmb.memory.size >> PAGE_SHIFT;
364 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
366 #ifdef CONFIG_NEED_MULTIPLE_NODES
367 for_each_online_node(nid) {
368 if (NODE_DATA(nid)->node_spanned_pages != 0) {
369 printk("freeing bootmem node %d\n", nid);
371 free_all_bootmem_node(NODE_DATA(nid));
376 totalram_pages += free_all_bootmem();
378 for_each_online_pgdat(pgdat) {
379 for (i = 0; i < pgdat->node_spanned_pages; i++) {
380 if (!pfn_valid(pgdat->node_start_pfn + i))
382 page = pgdat_page_nr(pgdat, i);
383 if (PageReserved(page))
388 codesize = (unsigned long)&_sdata - (unsigned long)&_stext;
389 datasize = (unsigned long)&_edata - (unsigned long)&_sdata;
390 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
391 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;
393 #ifdef CONFIG_HIGHMEM
395 unsigned long pfn, highmem_mapnr;
397 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
398 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
399 struct page *page = pfn_to_page(pfn);
400 if (lmb_is_reserved(pfn << PAGE_SHIFT))
402 ClearPageReserved(page);
403 init_page_count(page);
408 totalram_pages += totalhigh_pages;
409 printk(KERN_DEBUG "High memory: %luk\n",
410 totalhigh_pages << (PAGE_SHIFT-10));
412 #endif /* CONFIG_HIGHMEM */
414 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, "
415 "%luk reserved, %luk data, %luk bss, %luk init)\n",
416 (unsigned long)nr_free_pages() << (PAGE_SHIFT-10),
417 num_physpages << (PAGE_SHIFT-10),
419 reservedpages << (PAGE_SHIFT-10),
428 * This is called when a page has been modified by the kernel.
429 * It just marks the page as not i-cache clean. We do the i-cache
430 * flush later when the page is given to a user process, if necessary.
432 void flush_dcache_page(struct page *page)
434 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
436 /* avoid an atomic op if possible */
437 if (test_bit(PG_arch_1, &page->flags))
438 clear_bit(PG_arch_1, &page->flags);
440 EXPORT_SYMBOL(flush_dcache_page);
442 void flush_dcache_icache_page(struct page *page)
445 void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE);
446 __flush_dcache_icache(start);
447 kunmap_atomic(start, KM_PPC_SYNC_ICACHE);
448 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64)
449 /* On 8xx there is no need to kmap since highmem is not supported */
450 __flush_dcache_icache(page_address(page));
452 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
456 void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
461 * We shouldnt have to do this, but some versions of glibc
462 * require it (ld.so assumes zero filled pages are icache clean)
465 flush_dcache_page(pg);
467 EXPORT_SYMBOL(clear_user_page);
469 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
472 copy_page(vto, vfrom);
475 * We should be able to use the following optimisation, however
476 * there are two problems.
477 * Firstly a bug in some versions of binutils meant PLT sections
478 * were not marked executable.
479 * Secondly the first word in the GOT section is blrl, used
480 * to establish the GOT address. Until recently the GOT was
481 * not marked executable.
485 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
489 flush_dcache_page(pg);
492 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
493 unsigned long addr, int len)
497 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
498 flush_icache_range(maddr, maddr + len);
501 EXPORT_SYMBOL(flush_icache_user_range);
504 * This is called at the end of handling a user page fault, when the
505 * fault has been handled by updating a PTE in the linux page tables.
506 * We use it to preload an HPTE into the hash table corresponding to
507 * the updated linux PTE.
509 * This must always be called with the pte lock held.
511 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
514 #ifdef CONFIG_PPC_STD_MMU
515 unsigned long access = 0, trap;
517 unsigned long pfn = pte_pfn(pte);
519 /* handle i-cache coherency */
520 if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) &&
521 !cpu_has_feature(CPU_FTR_NOEXECUTE) &&
523 struct page *page = pfn_to_page(pfn);
525 /* On 8xx, cache control instructions (particularly
526 * "dcbst" from flush_dcache_icache) fault as write
527 * operation if there is an unpopulated TLB entry
528 * for the address in question. To workaround that,
529 * we invalidate the TLB here, thus avoiding dcbst
532 _tlbie(address, 0 /* 8xx doesn't care about PID */);
534 /* The _PAGE_USER test should really be _PAGE_EXEC, but
535 * older glibc versions execute some code from no-exec
536 * pages, which for now we are supporting. If exec-only
537 * pages are ever implemented, this will have to change.
539 if (!PageReserved(page) && (pte_val(pte) & _PAGE_USER)
540 && !test_bit(PG_arch_1, &page->flags)) {
541 if (vma->vm_mm == current->active_mm) {
542 __flush_dcache_icache((void *) address);
544 flush_dcache_icache_page(page);
545 set_bit(PG_arch_1, &page->flags);
549 #ifdef CONFIG_PPC_STD_MMU
550 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
551 if (!pte_young(pte) || address >= TASK_SIZE)
554 /* We try to figure out if we are coming from an instruction
555 * access fault and pass that down to __hash_page so we avoid
556 * double-faulting on execution of fresh text. We have to test
557 * for regs NULL since init will get here first thing at boot
559 * We also avoid filling the hash if not coming from a fault
561 if (current->thread.regs == NULL)
563 trap = TRAP(current->thread.regs);
565 access |= _PAGE_EXEC;
566 else if (trap != 0x300)
568 hash_preload(vma->vm_mm, address, access, trap);
569 #endif /* CONFIG_PPC_STD_MMU */