2 * PowerPC64 port by Mike Corrigan and Dave Engebretsen
3 * {mikejc|engebret}@us.ibm.com
5 * Copyright (c) 2000 Mike Corrigan <mikejc@us.ibm.com>
7 * SMP scalability work:
8 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
13 * PowerPC Hashed Page Table functions
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
24 #include <linux/spinlock.h>
25 #include <linux/errno.h>
26 #include <linux/sched.h>
27 #include <linux/proc_fs.h>
28 #include <linux/stat.h>
29 #include <linux/sysctl.h>
30 #include <linux/ctype.h>
31 #include <linux/cache.h>
32 #include <linux/init.h>
33 #include <linux/signal.h>
34 #include <linux/lmb.h>
36 #include <asm/processor.h>
37 #include <asm/pgtable.h>
39 #include <asm/mmu_context.h>
41 #include <asm/types.h>
42 #include <asm/system.h>
43 #include <asm/uaccess.h>
44 #include <asm/machdep.h>
46 #include <asm/abs_addr.h>
47 #include <asm/tlbflush.h>
51 #include <asm/cacheflush.h>
52 #include <asm/cputable.h>
53 #include <asm/sections.h>
58 #define DBG(fmt...) udbg_printf(fmt)
64 #define DBG_LOW(fmt...) udbg_printf(fmt)
66 #define DBG_LOW(fmt...)
74 * Note: pte --> Linux PTE
75 * HPTE --> PowerPC Hashed Page Table Entry
78 * htab_initialize is called with the MMU off (of course), but
79 * the kernel has been copied down to zero so it can directly
80 * reference global data. At this point it is very difficult
81 * to print debug info.
86 extern unsigned long dart_tablebase;
87 #endif /* CONFIG_U3_DART */
89 static unsigned long _SDR1;
90 struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
92 struct hash_pte *htab_address;
93 unsigned long htab_size_bytes;
94 unsigned long htab_hash_mask;
95 EXPORT_SYMBOL_GPL(htab_hash_mask);
96 int mmu_linear_psize = MMU_PAGE_4K;
97 int mmu_virtual_psize = MMU_PAGE_4K;
98 int mmu_vmalloc_psize = MMU_PAGE_4K;
99 #ifdef CONFIG_SPARSEMEM_VMEMMAP
100 int mmu_vmemmap_psize = MMU_PAGE_4K;
102 int mmu_io_psize = MMU_PAGE_4K;
103 int mmu_kernel_ssize = MMU_SEGSIZE_256M;
104 int mmu_highuser_ssize = MMU_SEGSIZE_256M;
105 u16 mmu_slb_size = 64;
106 EXPORT_SYMBOL_GPL(mmu_slb_size);
107 #ifdef CONFIG_HUGETLB_PAGE
108 unsigned int HPAGE_SHIFT;
110 #ifdef CONFIG_PPC_64K_PAGES
111 int mmu_ci_restrictions;
113 #ifdef CONFIG_DEBUG_PAGEALLOC
114 static u8 *linear_map_hash_slots;
115 static unsigned long linear_map_hash_count;
116 static DEFINE_SPINLOCK(linear_map_hash_lock);
117 #endif /* CONFIG_DEBUG_PAGEALLOC */
119 /* There are definitions of page sizes arrays to be used when none
120 * is provided by the firmware.
123 /* Pre-POWER4 CPUs (4k pages only)
125 static struct mmu_psize_def mmu_psize_defaults_old[] = {
135 /* POWER4, GPUL, POWER5
137 * Support for 16Mb large pages
139 static struct mmu_psize_def mmu_psize_defaults_gp[] = {
156 static unsigned long htab_convert_pte_flags(unsigned long pteflags)
158 unsigned long rflags = pteflags & 0x1fa;
160 /* _PAGE_EXEC -> NOEXEC */
161 if ((pteflags & _PAGE_EXEC) == 0)
164 /* PP bits. PAGE_USER is already PP bit 0x2, so we only
165 * need to add in 0x1 if it's a read-only user page
167 if ((pteflags & _PAGE_USER) && !((pteflags & _PAGE_RW) &&
168 (pteflags & _PAGE_DIRTY)))
172 return rflags | HPTE_R_C;
175 int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
176 unsigned long pstart, unsigned long prot,
177 int psize, int ssize)
179 unsigned long vaddr, paddr;
180 unsigned int step, shift;
183 shift = mmu_psize_defs[psize].shift;
186 prot = htab_convert_pte_flags(prot);
188 DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n",
189 vstart, vend, pstart, prot, psize, ssize);
191 for (vaddr = vstart, paddr = pstart; vaddr < vend;
192 vaddr += step, paddr += step) {
193 unsigned long hash, hpteg;
194 unsigned long vsid = get_kernel_vsid(vaddr, ssize);
195 unsigned long va = hpt_va(vaddr, vsid, ssize);
196 unsigned long tprot = prot;
198 /* Make kernel text executable */
199 if (overlaps_kernel_text(vaddr, vaddr + step))
202 hash = hpt_hash(va, shift, ssize);
203 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
205 BUG_ON(!ppc_md.hpte_insert);
206 ret = ppc_md.hpte_insert(hpteg, va, paddr, tprot,
207 HPTE_V_BOLTED, psize, ssize);
211 #ifdef CONFIG_DEBUG_PAGEALLOC
212 if ((paddr >> PAGE_SHIFT) < linear_map_hash_count)
213 linear_map_hash_slots[paddr >> PAGE_SHIFT] = ret | 0x80;
214 #endif /* CONFIG_DEBUG_PAGEALLOC */
216 return ret < 0 ? ret : 0;
219 #ifdef CONFIG_MEMORY_HOTPLUG
220 static int htab_remove_mapping(unsigned long vstart, unsigned long vend,
221 int psize, int ssize)
224 unsigned int step, shift;
226 shift = mmu_psize_defs[psize].shift;
229 if (!ppc_md.hpte_removebolted) {
230 printk(KERN_WARNING "Platform doesn't implement "
231 "hpte_removebolted\n");
235 for (vaddr = vstart; vaddr < vend; vaddr += step)
236 ppc_md.hpte_removebolted(vaddr, psize, ssize);
240 #endif /* CONFIG_MEMORY_HOTPLUG */
242 static int __init htab_dt_scan_seg_sizes(unsigned long node,
243 const char *uname, int depth,
246 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
248 unsigned long size = 0;
250 /* We are scanning "cpu" nodes only */
251 if (type == NULL || strcmp(type, "cpu") != 0)
254 prop = (u32 *)of_get_flat_dt_prop(node, "ibm,processor-segment-sizes",
258 for (; size >= 4; size -= 4, ++prop) {
260 DBG("1T segment support detected\n");
261 cur_cpu_spec->cpu_features |= CPU_FTR_1T_SEGMENT;
265 cur_cpu_spec->cpu_features &= ~CPU_FTR_NO_SLBIE_B;
269 static void __init htab_init_seg_sizes(void)
271 of_scan_flat_dt(htab_dt_scan_seg_sizes, NULL);
274 static int __init htab_dt_scan_page_sizes(unsigned long node,
275 const char *uname, int depth,
278 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
280 unsigned long size = 0;
282 /* We are scanning "cpu" nodes only */
283 if (type == NULL || strcmp(type, "cpu") != 0)
286 prop = (u32 *)of_get_flat_dt_prop(node,
287 "ibm,segment-page-sizes", &size);
289 DBG("Page sizes from device-tree:\n");
291 cur_cpu_spec->cpu_features &= ~(CPU_FTR_16M_PAGE);
293 unsigned int shift = prop[0];
294 unsigned int slbenc = prop[1];
295 unsigned int lpnum = prop[2];
296 unsigned int lpenc = 0;
297 struct mmu_psize_def *def;
300 size -= 3; prop += 3;
301 while(size > 0 && lpnum) {
302 if (prop[0] == shift)
304 prop += 2; size -= 2;
319 cur_cpu_spec->cpu_features |= CPU_FTR_16M_PAGE;
327 def = &mmu_psize_defs[idx];
332 def->avpnm = (1 << (shift - 23)) - 1;
335 /* We don't know for sure what's up with tlbiel, so
336 * for now we only set it for 4K and 64K pages
338 if (idx == MMU_PAGE_4K || idx == MMU_PAGE_64K)
343 DBG(" %d: shift=%02x, sllp=%04lx, avpnm=%08lx, "
344 "tlbiel=%d, penc=%d\n",
345 idx, shift, def->sllp, def->avpnm, def->tlbiel,
353 #ifdef CONFIG_HUGETLB_PAGE
354 /* Scan for 16G memory blocks that have been set aside for huge pages
355 * and reserve those blocks for 16G huge pages.
357 static int __init htab_dt_scan_hugepage_blocks(unsigned long node,
358 const char *uname, int depth,
360 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
361 unsigned long *addr_prop;
362 u32 *page_count_prop;
363 unsigned int expected_pages;
364 long unsigned int phys_addr;
365 long unsigned int block_size;
367 /* We are scanning "memory" nodes only */
368 if (type == NULL || strcmp(type, "memory") != 0)
371 /* This property is the log base 2 of the number of virtual pages that
372 * will represent this memory block. */
373 page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL);
374 if (page_count_prop == NULL)
376 expected_pages = (1 << page_count_prop[0]);
377 addr_prop = of_get_flat_dt_prop(node, "reg", NULL);
378 if (addr_prop == NULL)
380 phys_addr = addr_prop[0];
381 block_size = addr_prop[1];
382 if (block_size != (16 * GB))
384 printk(KERN_INFO "Huge page(16GB) memory: "
385 "addr = 0x%lX size = 0x%lX pages = %d\n",
386 phys_addr, block_size, expected_pages);
387 if (phys_addr + (16 * GB) <= lmb_end_of_DRAM()) {
388 lmb_reserve(phys_addr, block_size * expected_pages);
389 add_gpage(phys_addr, block_size, expected_pages);
393 #endif /* CONFIG_HUGETLB_PAGE */
395 static void __init htab_init_page_sizes(void)
399 /* Default to 4K pages only */
400 memcpy(mmu_psize_defs, mmu_psize_defaults_old,
401 sizeof(mmu_psize_defaults_old));
404 * Try to find the available page sizes in the device-tree
406 rc = of_scan_flat_dt(htab_dt_scan_page_sizes, NULL);
407 if (rc != 0) /* Found */
411 * Not in the device-tree, let's fallback on known size
412 * list for 16M capable GP & GR
414 if (cpu_has_feature(CPU_FTR_16M_PAGE))
415 memcpy(mmu_psize_defs, mmu_psize_defaults_gp,
416 sizeof(mmu_psize_defaults_gp));
418 #ifndef CONFIG_DEBUG_PAGEALLOC
420 * Pick a size for the linear mapping. Currently, we only support
421 * 16M, 1M and 4K which is the default
423 if (mmu_psize_defs[MMU_PAGE_16M].shift)
424 mmu_linear_psize = MMU_PAGE_16M;
425 else if (mmu_psize_defs[MMU_PAGE_1M].shift)
426 mmu_linear_psize = MMU_PAGE_1M;
427 #endif /* CONFIG_DEBUG_PAGEALLOC */
429 #ifdef CONFIG_PPC_64K_PAGES
431 * Pick a size for the ordinary pages. Default is 4K, we support
432 * 64K for user mappings and vmalloc if supported by the processor.
433 * We only use 64k for ioremap if the processor
434 * (and firmware) support cache-inhibited large pages.
435 * If not, we use 4k and set mmu_ci_restrictions so that
436 * hash_page knows to switch processes that use cache-inhibited
437 * mappings to 4k pages.
439 if (mmu_psize_defs[MMU_PAGE_64K].shift) {
440 mmu_virtual_psize = MMU_PAGE_64K;
441 mmu_vmalloc_psize = MMU_PAGE_64K;
442 if (mmu_linear_psize == MMU_PAGE_4K)
443 mmu_linear_psize = MMU_PAGE_64K;
444 if (cpu_has_feature(CPU_FTR_CI_LARGE_PAGE)) {
446 * Don't use 64k pages for ioremap on pSeries, since
447 * that would stop us accessing the HEA ethernet.
449 if (!machine_is(pseries))
450 mmu_io_psize = MMU_PAGE_64K;
452 mmu_ci_restrictions = 1;
454 #endif /* CONFIG_PPC_64K_PAGES */
456 #ifdef CONFIG_SPARSEMEM_VMEMMAP
457 /* We try to use 16M pages for vmemmap if that is supported
458 * and we have at least 1G of RAM at boot
460 if (mmu_psize_defs[MMU_PAGE_16M].shift &&
461 lmb_phys_mem_size() >= 0x40000000)
462 mmu_vmemmap_psize = MMU_PAGE_16M;
463 else if (mmu_psize_defs[MMU_PAGE_64K].shift)
464 mmu_vmemmap_psize = MMU_PAGE_64K;
466 mmu_vmemmap_psize = MMU_PAGE_4K;
467 #endif /* CONFIG_SPARSEMEM_VMEMMAP */
469 printk(KERN_DEBUG "Page orders: linear mapping = %d, "
470 "virtual = %d, io = %d"
471 #ifdef CONFIG_SPARSEMEM_VMEMMAP
475 mmu_psize_defs[mmu_linear_psize].shift,
476 mmu_psize_defs[mmu_virtual_psize].shift,
477 mmu_psize_defs[mmu_io_psize].shift
478 #ifdef CONFIG_SPARSEMEM_VMEMMAP
479 ,mmu_psize_defs[mmu_vmemmap_psize].shift
483 #ifdef CONFIG_HUGETLB_PAGE
484 /* Reserve 16G huge page memory sections for huge pages */
485 of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
486 #endif /* CONFIG_HUGETLB_PAGE */
489 static int __init htab_dt_scan_pftsize(unsigned long node,
490 const char *uname, int depth,
493 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
496 /* We are scanning "cpu" nodes only */
497 if (type == NULL || strcmp(type, "cpu") != 0)
500 prop = (u32 *)of_get_flat_dt_prop(node, "ibm,pft-size", NULL);
502 /* pft_size[0] is the NUMA CEC cookie */
503 ppc64_pft_size = prop[1];
509 static unsigned long __init htab_get_table_size(void)
511 unsigned long mem_size, rnd_mem_size, pteg_count, psize;
513 /* If hash size isn't already provided by the platform, we try to
514 * retrieve it from the device-tree. If it's not there neither, we
515 * calculate it now based on the total RAM size
517 if (ppc64_pft_size == 0)
518 of_scan_flat_dt(htab_dt_scan_pftsize, NULL);
520 return 1UL << ppc64_pft_size;
522 /* round mem_size up to next power of 2 */
523 mem_size = lmb_phys_mem_size();
524 rnd_mem_size = 1UL << __ilog2(mem_size);
525 if (rnd_mem_size < mem_size)
529 psize = mmu_psize_defs[mmu_virtual_psize].shift;
530 pteg_count = max(rnd_mem_size >> (psize + 1), 1UL << 11);
532 return pteg_count << 7;
535 #ifdef CONFIG_MEMORY_HOTPLUG
536 void create_section_mapping(unsigned long start, unsigned long end)
538 BUG_ON(htab_bolt_mapping(start, end, __pa(start),
539 pgprot_val(PAGE_KERNEL), mmu_linear_psize,
543 int remove_section_mapping(unsigned long start, unsigned long end)
545 return htab_remove_mapping(start, end, mmu_linear_psize,
548 #endif /* CONFIG_MEMORY_HOTPLUG */
550 static inline void make_bl(unsigned int *insn_addr, void *func)
552 unsigned long funcp = *((unsigned long *)func);
553 int offset = funcp - (unsigned long)insn_addr;
555 *insn_addr = (unsigned int)(0x48000001 | (offset & 0x03fffffc));
556 flush_icache_range((unsigned long)insn_addr, 4+
557 (unsigned long)insn_addr);
560 static void __init htab_finish_init(void)
562 extern unsigned int *htab_call_hpte_insert1;
563 extern unsigned int *htab_call_hpte_insert2;
564 extern unsigned int *htab_call_hpte_remove;
565 extern unsigned int *htab_call_hpte_updatepp;
567 #ifdef CONFIG_PPC_HAS_HASH_64K
568 extern unsigned int *ht64_call_hpte_insert1;
569 extern unsigned int *ht64_call_hpte_insert2;
570 extern unsigned int *ht64_call_hpte_remove;
571 extern unsigned int *ht64_call_hpte_updatepp;
573 make_bl(ht64_call_hpte_insert1, ppc_md.hpte_insert);
574 make_bl(ht64_call_hpte_insert2, ppc_md.hpte_insert);
575 make_bl(ht64_call_hpte_remove, ppc_md.hpte_remove);
576 make_bl(ht64_call_hpte_updatepp, ppc_md.hpte_updatepp);
577 #endif /* CONFIG_PPC_HAS_HASH_64K */
579 make_bl(htab_call_hpte_insert1, ppc_md.hpte_insert);
580 make_bl(htab_call_hpte_insert2, ppc_md.hpte_insert);
581 make_bl(htab_call_hpte_remove, ppc_md.hpte_remove);
582 make_bl(htab_call_hpte_updatepp, ppc_md.hpte_updatepp);
585 static void __init htab_initialize(void)
588 unsigned long pteg_count;
590 unsigned long base = 0, size = 0, limit;
593 DBG(" -> htab_initialize()\n");
595 /* Initialize segment sizes */
596 htab_init_seg_sizes();
598 /* Initialize page sizes */
599 htab_init_page_sizes();
601 if (cpu_has_feature(CPU_FTR_1T_SEGMENT)) {
602 mmu_kernel_ssize = MMU_SEGSIZE_1T;
603 mmu_highuser_ssize = MMU_SEGSIZE_1T;
604 printk(KERN_INFO "Using 1TB segments\n");
608 * Calculate the required size of the htab. We want the number of
609 * PTEGs to equal one half the number of real pages.
611 htab_size_bytes = htab_get_table_size();
612 pteg_count = htab_size_bytes >> 7;
614 htab_hash_mask = pteg_count - 1;
616 if (firmware_has_feature(FW_FEATURE_LPAR)) {
617 /* Using a hypervisor which owns the htab */
621 /* Find storage for the HPT. Must be contiguous in
622 * the absolute address space. On cell we want it to be
623 * in the first 2 Gig so we can use it for IOMMU hacks.
625 if (machine_is(cell))
630 table = lmb_alloc_base(htab_size_bytes, htab_size_bytes, limit);
632 DBG("Hash table allocated at %lx, size: %lx\n", table,
635 htab_address = abs_to_virt(table);
637 /* htab absolute addr + encoded htabsize */
638 _SDR1 = table + __ilog2(pteg_count) - 11;
640 /* Initialize the HPT with no entries */
641 memset((void *)table, 0, htab_size_bytes);
644 mtspr(SPRN_SDR1, _SDR1);
647 prot = pgprot_val(PAGE_KERNEL);
649 #ifdef CONFIG_DEBUG_PAGEALLOC
650 linear_map_hash_count = lmb_end_of_DRAM() >> PAGE_SHIFT;
651 linear_map_hash_slots = __va(lmb_alloc_base(linear_map_hash_count,
653 memset(linear_map_hash_slots, 0, linear_map_hash_count);
654 #endif /* CONFIG_DEBUG_PAGEALLOC */
656 /* On U3 based machines, we need to reserve the DART area and
657 * _NOT_ map it to avoid cache paradoxes as it's remapped non
661 /* create bolted the linear mapping in the hash table */
662 for (i=0; i < lmb.memory.cnt; i++) {
663 base = (unsigned long)__va(lmb.memory.region[i].base);
664 size = lmb.memory.region[i].size;
666 DBG("creating mapping for region: %lx..%lx (prot: %lx)\n",
669 #ifdef CONFIG_U3_DART
670 /* Do not map the DART space. Fortunately, it will be aligned
671 * in such a way that it will not cross two lmb regions and
672 * will fit within a single 16Mb page.
673 * The DART space is assumed to be a full 16Mb region even if
674 * we only use 2Mb of that space. We will use more of it later
675 * for AGP GART. We have to use a full 16Mb large page.
677 DBG("DART base: %lx\n", dart_tablebase);
679 if (dart_tablebase != 0 && dart_tablebase >= base
680 && dart_tablebase < (base + size)) {
681 unsigned long dart_table_end = dart_tablebase + 16 * MB;
682 if (base != dart_tablebase)
683 BUG_ON(htab_bolt_mapping(base, dart_tablebase,
687 if ((base + size) > dart_table_end)
688 BUG_ON(htab_bolt_mapping(dart_tablebase+16*MB,
690 __pa(dart_table_end),
696 #endif /* CONFIG_U3_DART */
697 BUG_ON(htab_bolt_mapping(base, base + size, __pa(base),
698 prot, mmu_linear_psize, mmu_kernel_ssize));
702 * If we have a memory_limit and we've allocated TCEs then we need to
703 * explicitly map the TCE area at the top of RAM. We also cope with the
704 * case that the TCEs start below memory_limit.
705 * tce_alloc_start/end are 16MB aligned so the mapping should work
706 * for either 4K or 16MB pages.
708 if (tce_alloc_start) {
709 tce_alloc_start = (unsigned long)__va(tce_alloc_start);
710 tce_alloc_end = (unsigned long)__va(tce_alloc_end);
712 if (base + size >= tce_alloc_start)
713 tce_alloc_start = base + size + 1;
715 BUG_ON(htab_bolt_mapping(tce_alloc_start, tce_alloc_end,
716 __pa(tce_alloc_start), prot,
717 mmu_linear_psize, mmu_kernel_ssize));
722 DBG(" <- htab_initialize()\n");
727 void __init early_init_mmu(void)
729 /* Setup initial STAB address in the PACA */
730 get_paca()->stab_real = __pa((u64)&initial_stab);
731 get_paca()->stab_addr = (u64)&initial_stab;
733 /* Initialize the MMU Hash table and create the linear mapping
734 * of memory. Has to be done before stab/slb initialization as
735 * this is currently where the page size encoding is obtained
739 /* Initialize stab / SLB management except on iSeries
741 if (cpu_has_feature(CPU_FTR_SLB))
743 else if (!firmware_has_feature(FW_FEATURE_ISERIES))
744 stab_initialize(get_paca()->stab_real);
748 void __cpuinit early_init_mmu_secondary(void)
750 /* Initialize hash table for that CPU */
751 if (!firmware_has_feature(FW_FEATURE_LPAR))
752 mtspr(SPRN_SDR1, _SDR1);
754 /* Initialize STAB/SLB. We use a virtual address as it works
755 * in real mode on pSeries and we want a virutal address on
758 if (cpu_has_feature(CPU_FTR_SLB))
761 stab_initialize(get_paca()->stab_addr);
763 #endif /* CONFIG_SMP */
766 * Called by asm hashtable.S for doing lazy icache flush
768 unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
772 if (!pfn_valid(pte_pfn(pte)))
775 page = pte_page(pte);
778 if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) {
780 flush_dcache_icache_page(page);
781 set_bit(PG_arch_1, &page->flags);
788 #ifdef CONFIG_PPC_MM_SLICES
789 unsigned int get_paca_psize(unsigned long addr)
791 unsigned long index, slices;
793 if (addr < SLICE_LOW_TOP) {
794 slices = get_paca()->context.low_slices_psize;
795 index = GET_LOW_SLICE_INDEX(addr);
797 slices = get_paca()->context.high_slices_psize;
798 index = GET_HIGH_SLICE_INDEX(addr);
800 return (slices >> (index * 4)) & 0xF;
804 unsigned int get_paca_psize(unsigned long addr)
806 return get_paca()->context.user_psize;
811 * Demote a segment to using 4k pages.
812 * For now this makes the whole process use 4k pages.
814 #ifdef CONFIG_PPC_64K_PAGES
815 void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
817 if (get_slice_psize(mm, addr) == MMU_PAGE_4K)
819 slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K);
820 #ifdef CONFIG_SPU_BASE
821 spu_flush_all_slbs(mm);
823 if (get_paca_psize(addr) != MMU_PAGE_4K) {
824 get_paca()->context = mm->context;
825 slb_flush_and_rebolt();
828 #endif /* CONFIG_PPC_64K_PAGES */
830 #ifdef CONFIG_PPC_SUBPAGE_PROT
832 * This looks up a 2-bit protection code for a 4k subpage of a 64k page.
833 * Userspace sets the subpage permissions using the subpage_prot system call.
835 * Result is 0: full permissions, _PAGE_RW: read-only,
836 * _PAGE_USER or _PAGE_USER|_PAGE_RW: no access.
838 static int subpage_protection(struct mm_struct *mm, unsigned long ea)
840 struct subpage_prot_table *spt = &mm->context.spt;
844 if (ea >= spt->maxaddr)
846 if (ea < 0x100000000) {
847 /* addresses below 4GB use spt->low_prot */
848 sbpm = spt->low_prot;
850 sbpm = spt->protptrs[ea >> SBP_L3_SHIFT];
854 sbpp = sbpm[(ea >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1)];
857 spp = sbpp[(ea >> PAGE_SHIFT) & (SBP_L1_COUNT - 1)];
859 /* extract 2-bit bitfield for this 4k subpage */
860 spp >>= 30 - 2 * ((ea >> 12) & 0xf);
862 /* turn 0,1,2,3 into combination of _PAGE_USER and _PAGE_RW */
863 spp = ((spp & 2) ? _PAGE_USER : 0) | ((spp & 1) ? _PAGE_RW : 0);
867 #else /* CONFIG_PPC_SUBPAGE_PROT */
868 static inline int subpage_protection(struct mm_struct *mm, unsigned long ea)
876 * 1 - normal page fault
877 * -1 - critical hash insertion error
878 * -2 - access not permitted by subpage protection mechanism
880 int hash_page(unsigned long ea, unsigned long access, unsigned long trap)
884 struct mm_struct *mm;
887 const struct cpumask *tmp;
888 int rc, user_region = 0, local = 0;
891 DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n",
894 if ((ea & ~REGION_MASK) >= PGTABLE_RANGE) {
895 DBG_LOW(" out of pgtable range !\n");
899 /* Get region & vsid */
900 switch (REGION_ID(ea)) {
905 DBG_LOW(" user region with no mm !\n");
908 psize = get_slice_psize(mm, ea);
909 ssize = user_segment_size(ea);
910 vsid = get_vsid(mm->context.id, ea, ssize);
912 case VMALLOC_REGION_ID:
914 vsid = get_kernel_vsid(ea, mmu_kernel_ssize);
915 if (ea < VMALLOC_END)
916 psize = mmu_vmalloc_psize;
918 psize = mmu_io_psize;
919 ssize = mmu_kernel_ssize;
923 * Send the problem up to do_page_fault
927 DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid);
934 /* Check CPU locality */
935 tmp = cpumask_of(smp_processor_id());
936 if (user_region && cpumask_equal(mm_cpumask(mm), tmp))
939 #ifndef CONFIG_PPC_64K_PAGES
940 /* If we use 4K pages and our psize is not 4K, then we might
941 * be hitting a special driver mapping, and need to align the
942 * address before we fetch the PTE.
944 * It could also be a hugepage mapping, in which case this is
945 * not necessary, but it's not harmful, either.
947 if (psize != MMU_PAGE_4K)
948 ea &= ~((1ul << mmu_psize_defs[psize].shift) - 1);
949 #endif /* CONFIG_PPC_64K_PAGES */
951 /* Get PTE and page size from page tables */
952 ptep = find_linux_pte_or_hugepte(pgdir, ea, &hugeshift);
953 if (ptep == NULL || !pte_present(*ptep)) {
954 DBG_LOW(" no PTE !\n");
958 #ifdef CONFIG_HUGETLB_PAGE
960 return __hash_page_huge(ea, access, vsid, ptep, trap, local,
961 ssize, hugeshift, psize);
962 #endif /* CONFIG_HUGETLB_PAGE */
964 #ifndef CONFIG_PPC_64K_PAGES
965 DBG_LOW(" i-pte: %016lx\n", pte_val(*ptep));
967 DBG_LOW(" i-pte: %016lx %016lx\n", pte_val(*ptep),
968 pte_val(*(ptep + PTRS_PER_PTE)));
970 /* Pre-check access permissions (will be re-checked atomically
971 * in __hash_page_XX but this pre-check is a fast path
973 if (access & ~pte_val(*ptep)) {
974 DBG_LOW(" no access !\n");
978 /* Do actual hashing */
979 #ifdef CONFIG_PPC_64K_PAGES
980 /* If _PAGE_4K_PFN is set, make sure this is a 4k segment */
981 if ((pte_val(*ptep) & _PAGE_4K_PFN) && psize == MMU_PAGE_64K) {
982 demote_segment_4k(mm, ea);
986 /* If this PTE is non-cacheable and we have restrictions on
987 * using non cacheable large pages, then we switch to 4k
989 if (mmu_ci_restrictions && psize == MMU_PAGE_64K &&
990 (pte_val(*ptep) & _PAGE_NO_CACHE)) {
992 demote_segment_4k(mm, ea);
994 } else if (ea < VMALLOC_END) {
996 * some driver did a non-cacheable mapping
997 * in vmalloc space, so switch vmalloc
1000 printk(KERN_ALERT "Reducing vmalloc segment "
1001 "to 4kB pages because of "
1002 "non-cacheable mapping\n");
1003 psize = mmu_vmalloc_psize = MMU_PAGE_4K;
1004 #ifdef CONFIG_SPU_BASE
1005 spu_flush_all_slbs(mm);
1010 if (psize != get_paca_psize(ea)) {
1011 get_paca()->context = mm->context;
1012 slb_flush_and_rebolt();
1014 } else if (get_paca()->vmalloc_sllp !=
1015 mmu_psize_defs[mmu_vmalloc_psize].sllp) {
1016 get_paca()->vmalloc_sllp =
1017 mmu_psize_defs[mmu_vmalloc_psize].sllp;
1018 slb_vmalloc_update();
1020 #endif /* CONFIG_PPC_64K_PAGES */
1022 #ifdef CONFIG_PPC_HAS_HASH_64K
1023 if (psize == MMU_PAGE_64K)
1024 rc = __hash_page_64K(ea, access, vsid, ptep, trap, local, ssize);
1026 #endif /* CONFIG_PPC_HAS_HASH_64K */
1028 int spp = subpage_protection(mm, ea);
1032 rc = __hash_page_4K(ea, access, vsid, ptep, trap,
1036 #ifndef CONFIG_PPC_64K_PAGES
1037 DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep));
1039 DBG_LOW(" o-pte: %016lx %016lx\n", pte_val(*ptep),
1040 pte_val(*(ptep + PTRS_PER_PTE)));
1042 DBG_LOW(" -> rc=%d\n", rc);
1045 EXPORT_SYMBOL_GPL(hash_page);
1047 void hash_preload(struct mm_struct *mm, unsigned long ea,
1048 unsigned long access, unsigned long trap)
1053 unsigned long flags;
1057 BUG_ON(REGION_ID(ea) != USER_REGION_ID);
1059 #ifdef CONFIG_PPC_MM_SLICES
1060 /* We only prefault standard pages for now */
1061 if (unlikely(get_slice_psize(mm, ea) != mm->context.user_psize))
1065 DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx,"
1066 " trap=%lx\n", mm, mm->pgd, ea, access, trap);
1068 /* Get Linux PTE if available */
1072 ptep = find_linux_pte(pgdir, ea);
1076 #ifdef CONFIG_PPC_64K_PAGES
1077 /* If either _PAGE_4K_PFN or _PAGE_NO_CACHE is set (and we are on
1078 * a 64K kernel), then we don't preload, hash_page() will take
1079 * care of it once we actually try to access the page.
1080 * That way we don't have to duplicate all of the logic for segment
1081 * page size demotion here
1083 if (pte_val(*ptep) & (_PAGE_4K_PFN | _PAGE_NO_CACHE))
1085 #endif /* CONFIG_PPC_64K_PAGES */
1088 ssize = user_segment_size(ea);
1089 vsid = get_vsid(mm->context.id, ea, ssize);
1091 /* Hash doesn't like irqs */
1092 local_irq_save(flags);
1094 /* Is that local to this CPU ? */
1095 if (cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
1099 #ifdef CONFIG_PPC_HAS_HASH_64K
1100 if (mm->context.user_psize == MMU_PAGE_64K)
1101 __hash_page_64K(ea, access, vsid, ptep, trap, local, ssize);
1103 #endif /* CONFIG_PPC_HAS_HASH_64K */
1104 __hash_page_4K(ea, access, vsid, ptep, trap, local, ssize,
1105 subpage_protection(pgdir, ea));
1107 local_irq_restore(flags);
1110 /* WARNING: This is called from hash_low_64.S, if you change this prototype,
1111 * do not forget to update the assembly call site !
1113 void flush_hash_page(unsigned long va, real_pte_t pte, int psize, int ssize,
1116 unsigned long hash, index, shift, hidx, slot;
1118 DBG_LOW("flush_hash_page(va=%016lx)\n", va);
1119 pte_iterate_hashed_subpages(pte, psize, va, index, shift) {
1120 hash = hpt_hash(va, shift, ssize);
1121 hidx = __rpte_to_hidx(pte, index);
1122 if (hidx & _PTEIDX_SECONDARY)
1124 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
1125 slot += hidx & _PTEIDX_GROUP_IX;
1126 DBG_LOW(" sub %ld: hash=%lx, hidx=%lx\n", index, slot, hidx);
1127 ppc_md.hpte_invalidate(slot, va, psize, ssize, local);
1128 } pte_iterate_hashed_end();
1131 void flush_hash_range(unsigned long number, int local)
1133 if (ppc_md.flush_hash_range)
1134 ppc_md.flush_hash_range(number, local);
1137 struct ppc64_tlb_batch *batch =
1138 &__get_cpu_var(ppc64_tlb_batch);
1140 for (i = 0; i < number; i++)
1141 flush_hash_page(batch->vaddr[i], batch->pte[i],
1142 batch->psize, batch->ssize, local);
1147 * low_hash_fault is called when we the low level hash code failed
1148 * to instert a PTE due to an hypervisor error
1150 void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc)
1152 if (user_mode(regs)) {
1153 #ifdef CONFIG_PPC_SUBPAGE_PROT
1155 _exception(SIGSEGV, regs, SEGV_ACCERR, address);
1158 _exception(SIGBUS, regs, BUS_ADRERR, address);
1160 bad_page_fault(regs, address, SIGBUS);
1163 #ifdef CONFIG_DEBUG_PAGEALLOC
1164 static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi)
1166 unsigned long hash, hpteg;
1167 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize);
1168 unsigned long va = hpt_va(vaddr, vsid, mmu_kernel_ssize);
1169 unsigned long mode = htab_convert_pte_flags(PAGE_KERNEL);
1172 hash = hpt_hash(va, PAGE_SHIFT, mmu_kernel_ssize);
1173 hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
1175 ret = ppc_md.hpte_insert(hpteg, va, __pa(vaddr),
1176 mode, HPTE_V_BOLTED,
1177 mmu_linear_psize, mmu_kernel_ssize);
1179 spin_lock(&linear_map_hash_lock);
1180 BUG_ON(linear_map_hash_slots[lmi] & 0x80);
1181 linear_map_hash_slots[lmi] = ret | 0x80;
1182 spin_unlock(&linear_map_hash_lock);
1185 static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi)
1187 unsigned long hash, hidx, slot;
1188 unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize);
1189 unsigned long va = hpt_va(vaddr, vsid, mmu_kernel_ssize);
1191 hash = hpt_hash(va, PAGE_SHIFT, mmu_kernel_ssize);
1192 spin_lock(&linear_map_hash_lock);
1193 BUG_ON(!(linear_map_hash_slots[lmi] & 0x80));
1194 hidx = linear_map_hash_slots[lmi] & 0x7f;
1195 linear_map_hash_slots[lmi] = 0;
1196 spin_unlock(&linear_map_hash_lock);
1197 if (hidx & _PTEIDX_SECONDARY)
1199 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
1200 slot += hidx & _PTEIDX_GROUP_IX;
1201 ppc_md.hpte_invalidate(slot, va, mmu_linear_psize, mmu_kernel_ssize, 0);
1204 void kernel_map_pages(struct page *page, int numpages, int enable)
1206 unsigned long flags, vaddr, lmi;
1209 local_irq_save(flags);
1210 for (i = 0; i < numpages; i++, page++) {
1211 vaddr = (unsigned long)page_address(page);
1212 lmi = __pa(vaddr) >> PAGE_SHIFT;
1213 if (lmi >= linear_map_hash_count)
1216 kernel_map_linear_page(vaddr, lmi);
1218 kernel_unmap_linear_page(vaddr, lmi);
1220 local_irq_restore(flags);
1222 #endif /* CONFIG_DEBUG_PAGEALLOC */