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/export.h>
21 #include <linux/sched.h>
22 #include <linux/kernel.h>
23 #include <linux/errno.h>
24 #include <linux/string.h>
25 #include <linux/gfp.h>
26 #include <linux/types.h>
28 #include <linux/stddef.h>
29 #include <linux/init.h>
30 #include <linux/memblock.h>
31 #include <linux/highmem.h>
32 #include <linux/initrd.h>
33 #include <linux/pagemap.h>
34 #include <linux/suspend.h>
35 #include <linux/hugetlb.h>
36 #include <linux/slab.h>
37 #include <linux/vmalloc.h>
38 #include <linux/memremap.h>
40 #include <asm/pgalloc.h>
43 #include <asm/mmu_context.h>
44 #include <asm/pgtable.h>
47 #include <asm/machdep.h>
48 #include <asm/btext.h>
50 #include <asm/sections.h>
51 #include <asm/sparsemem.h>
53 #include <asm/fixmap.h>
54 #include <asm/swiotlb.h>
57 #include <mm/mmu_decl.h>
59 #ifndef CPU_FTR_COHERENT_ICACHE
60 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
61 #define CPU_FTR_NOEXECUTE 0
64 unsigned long long memory_limit;
65 bool init_mem_is_free;
69 EXPORT_SYMBOL(kmap_pte);
71 EXPORT_SYMBOL(kmap_prot);
73 static inline pte_t *virt_to_kpte(unsigned long vaddr)
75 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
76 vaddr), vaddr), vaddr);
80 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
81 unsigned long size, pgprot_t vma_prot)
83 if (ppc_md.phys_mem_access_prot)
84 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
86 if (!page_is_ram(pfn))
87 vma_prot = pgprot_noncached(vma_prot);
91 EXPORT_SYMBOL(phys_mem_access_prot);
93 #ifdef CONFIG_MEMORY_HOTPLUG
96 int memory_add_physaddr_to_nid(u64 start)
98 return hot_add_scn_to_nid(start);
102 int __weak create_section_mapping(unsigned long start, unsigned long end, int nid)
107 int __weak remove_section_mapping(unsigned long start, unsigned long end)
112 int __ref arch_add_memory(int nid, u64 start, u64 size,
113 struct mhp_restrictions *restrictions)
115 unsigned long start_pfn = start >> PAGE_SHIFT;
116 unsigned long nr_pages = size >> PAGE_SHIFT;
119 resize_hpt_for_hotplug(memblock_phys_mem_size());
121 start = (unsigned long)__va(start);
122 rc = create_section_mapping(start, start + size, nid);
124 pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n",
125 start, start + size, rc);
128 flush_inval_dcache_range(start, start + size);
130 return __add_pages(nid, start_pfn, nr_pages, restrictions);
133 #ifdef CONFIG_MEMORY_HOTREMOVE
134 void __ref arch_remove_memory(int nid, u64 start, u64 size,
135 struct vmem_altmap *altmap)
137 unsigned long start_pfn = start >> PAGE_SHIFT;
138 unsigned long nr_pages = size >> PAGE_SHIFT;
143 * If we have an altmap then we need to skip over any reserved PFNs
144 * when querying the zone.
146 page = pfn_to_page(start_pfn);
148 page += vmem_altmap_offset(altmap);
150 __remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
152 /* Remove htab bolted mappings for this section of memory */
153 start = (unsigned long)__va(start);
154 flush_inval_dcache_range(start, start + size);
155 ret = remove_section_mapping(start, start + size);
158 /* Ensure all vmalloc mappings are flushed in case they also
159 * hit that section of memory
163 if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC)
164 pr_warn("Hash collision while resizing HPT\n");
167 #endif /* CONFIG_MEMORY_HOTPLUG */
169 #ifndef CONFIG_NEED_MULTIPLE_NODES
170 void __init mem_topology_setup(void)
172 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
173 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
174 #ifdef CONFIG_HIGHMEM
175 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
178 /* Place all memblock_regions in the same node and merge contiguous
181 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
184 void __init initmem_init(void)
186 /* XXX need to clip this if using highmem? */
187 sparse_memory_present_with_active_regions(0);
191 /* mark pages that don't exist as nosave */
192 static int __init mark_nonram_nosave(void)
194 struct memblock_region *reg, *prev = NULL;
196 for_each_memblock(memory, reg) {
198 memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
199 register_nosave_region(memblock_region_memory_end_pfn(prev),
200 memblock_region_memory_base_pfn(reg));
205 #else /* CONFIG_NEED_MULTIPLE_NODES */
206 static int __init mark_nonram_nosave(void)
215 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
216 * everything else. GFP_DMA32 page allocations automatically fall back to
219 * By using 31-bit unconditionally, we can exploit ARCH_ZONE_DMA_BITS to
220 * inform the generic DMA mapping code. 32-bit only devices (if not handled
221 * by an IOMMU anyway) will take a first dip into ZONE_NORMAL and get
222 * otherwise served by ZONE_DMA.
224 static unsigned long max_zone_pfns[MAX_NR_ZONES];
227 * paging_init() sets up the page tables - in fact we've already done this.
229 void __init paging_init(void)
231 unsigned long long total_ram = memblock_phys_mem_size();
232 phys_addr_t top_of_ram = memblock_end_of_DRAM();
235 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
236 unsigned long end = __fix_to_virt(FIX_HOLE);
238 for (; v < end; v += PAGE_SIZE)
239 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
242 #ifdef CONFIG_HIGHMEM
243 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */
244 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
246 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
247 kmap_prot = PAGE_KERNEL;
248 #endif /* CONFIG_HIGHMEM */
250 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
251 (unsigned long long)top_of_ram, total_ram);
252 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
253 (long int)((top_of_ram - total_ram) >> 20));
255 #ifdef CONFIG_ZONE_DMA
256 max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT);
258 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
259 #ifdef CONFIG_HIGHMEM
260 max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
263 free_area_init_nodes(max_zone_pfns);
265 mark_nonram_nosave();
268 void __init mem_init(void)
271 * book3s is limited to 16 page sizes due to encoding this in
272 * a 4-bit field for slices.
274 BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
276 #ifdef CONFIG_SWIOTLB
280 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
281 set_max_mapnr(max_pfn);
284 #ifdef CONFIG_HIGHMEM
286 unsigned long pfn, highmem_mapnr;
288 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
289 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
290 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
291 struct page *page = pfn_to_page(pfn);
292 if (!memblock_is_reserved(paddr))
293 free_highmem_page(page);
296 #endif /* CONFIG_HIGHMEM */
298 #if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
300 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
301 * functions.... do it here for the non-smp case.
303 per_cpu(next_tlbcam_idx, smp_processor_id()) =
304 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
307 mem_init_print_info(NULL);
309 pr_info("Kernel virtual memory layout:\n");
311 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
312 KASAN_SHADOW_START, KASAN_SHADOW_END);
314 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
315 #ifdef CONFIG_HIGHMEM
316 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
317 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
318 #endif /* CONFIG_HIGHMEM */
319 #ifdef CONFIG_NOT_COHERENT_CACHE
320 pr_info(" * 0x%08lx..0x%08lx : consistent mem\n",
321 IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE);
322 #endif /* CONFIG_NOT_COHERENT_CACHE */
323 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
324 ioremap_bot, IOREMAP_TOP);
325 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
326 VMALLOC_START, VMALLOC_END);
327 #endif /* CONFIG_PPC32 */
330 void free_initmem(void)
332 ppc_md.progress = ppc_printk_progress;
334 init_mem_is_free = true;
335 free_initmem_default(POISON_FREE_INITMEM);
339 * This is called when a page has been modified by the kernel.
340 * It just marks the page as not i-cache clean. We do the i-cache
341 * flush later when the page is given to a user process, if necessary.
343 void flush_dcache_page(struct page *page)
345 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
347 /* avoid an atomic op if possible */
348 if (test_bit(PG_arch_1, &page->flags))
349 clear_bit(PG_arch_1, &page->flags);
351 EXPORT_SYMBOL(flush_dcache_page);
353 void flush_dcache_icache_page(struct page *page)
355 #ifdef CONFIG_HUGETLB_PAGE
356 if (PageCompound(page)) {
357 flush_dcache_icache_hugepage(page);
361 #if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC64)
362 /* On 8xx there is no need to kmap since highmem is not supported */
363 __flush_dcache_icache(page_address(page));
365 if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
366 void *start = kmap_atomic(page);
367 __flush_dcache_icache(start);
368 kunmap_atomic(start);
370 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
374 EXPORT_SYMBOL(flush_dcache_icache_page);
376 void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
381 * We shouldn't have to do this, but some versions of glibc
382 * require it (ld.so assumes zero filled pages are icache clean)
385 flush_dcache_page(pg);
387 EXPORT_SYMBOL(clear_user_page);
389 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
392 copy_page(vto, vfrom);
395 * We should be able to use the following optimisation, however
396 * there are two problems.
397 * Firstly a bug in some versions of binutils meant PLT sections
398 * were not marked executable.
399 * Secondly the first word in the GOT section is blrl, used
400 * to establish the GOT address. Until recently the GOT was
401 * not marked executable.
405 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
409 flush_dcache_page(pg);
412 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
413 unsigned long addr, int len)
417 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
418 flush_icache_range(maddr, maddr + len);
421 EXPORT_SYMBOL(flush_icache_user_range);
424 * This is called at the end of handling a user page fault, when the
425 * fault has been handled by updating a PTE in the linux page tables.
426 * We use it to preload an HPTE into the hash table corresponding to
427 * the updated linux PTE.
429 * This must always be called with the pte lock held.
431 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
434 #ifdef CONFIG_PPC_BOOK3S
436 * We don't need to worry about _PAGE_PRESENT here because we are
437 * called with either mm->page_table_lock held or ptl lock held
442 if (radix_enabled()) {
443 prefetch((void *)address);
447 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
448 if (!pte_young(*ptep) || address >= TASK_SIZE)
451 /* We try to figure out if we are coming from an instruction
452 * access fault and pass that down to __hash_page so we avoid
453 * double-faulting on execution of fresh text. We have to test
454 * for regs NULL since init will get here first thing at boot
456 * We also avoid filling the hash if not coming from a fault
459 trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL;
471 hash_preload(vma->vm_mm, address, is_exec, trap);
472 #endif /* CONFIG_PPC_BOOK3S */
473 #if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \
474 && defined(CONFIG_HUGETLB_PAGE)
475 if (is_vm_hugetlb_page(vma))
476 book3e_hugetlb_preload(vma, address, *ptep);
481 * System memory should not be in /proc/iomem but various tools expect it
484 static int __init add_system_ram_resources(void)
486 struct memblock_region *reg;
488 for_each_memblock(memory, reg) {
489 struct resource *res;
490 unsigned long base = reg->base;
491 unsigned long size = reg->size;
493 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
497 res->name = "System RAM";
499 res->end = base + size - 1;
500 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
501 WARN_ON(request_resource(&iomem_resource, res) < 0);
507 subsys_initcall(add_system_ram_resources);
509 #ifdef CONFIG_STRICT_DEVMEM
511 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
512 * is valid. The argument is a physical page number.
514 * Access has to be given to non-kernel-ram areas as well, these contain the
515 * PCI mmio resources as well as potential bios/acpi data regions.
517 int devmem_is_allowed(unsigned long pfn)
519 if (page_is_rtas_user_buf(pfn))
521 if (iomem_is_exclusive(PFN_PHYS(pfn)))
523 if (!page_is_ram(pfn))
527 #endif /* CONFIG_STRICT_DEVMEM */
530 * This is defined in kernel/resource.c but only powerpc needs to export it, for
531 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
533 EXPORT_SYMBOL_GPL(walk_system_ram_range);