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/export.h>
31 #include <linux/ctype.h>
32 #include <linux/cache.h>
33 #include <linux/init.h>
34 #include <linux/signal.h>
35 #include <linux/memblock.h>
37 #include <asm/processor.h>
38 #include <asm/pgtable.h>
40 #include <asm/mmu_context.h>
42 #include <asm/types.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>
56 #include <asm/code-patching.h>
57 #include <asm/fadump.h>
58 #include <asm/firmware.h>
61 #define DBG(fmt...) udbg_printf(fmt)
67 #define DBG_LOW(fmt...) udbg_printf(fmt)
69 #define DBG_LOW(fmt...)
77 * Note: pte --> Linux PTE
78 * HPTE --> PowerPC Hashed Page Table Entry
81 * htab_initialize is called with the MMU off (of course), but
82 * the kernel has been copied down to zero so it can directly
83 * reference global data. At this point it is very difficult
84 * to print debug info.
89 extern unsigned long dart_tablebase
;
90 #endif /* CONFIG_U3_DART */
92 static unsigned long _SDR1
;
93 struct mmu_psize_def mmu_psize_defs
[MMU_PAGE_COUNT
];
95 struct hash_pte
*htab_address
;
96 unsigned long htab_size_bytes
;
97 unsigned long htab_hash_mask
;
98 EXPORT_SYMBOL_GPL(htab_hash_mask
);
99 int mmu_linear_psize
= MMU_PAGE_4K
;
100 int mmu_virtual_psize
= MMU_PAGE_4K
;
101 int mmu_vmalloc_psize
= MMU_PAGE_4K
;
102 #ifdef CONFIG_SPARSEMEM_VMEMMAP
103 int mmu_vmemmap_psize
= MMU_PAGE_4K
;
105 int mmu_io_psize
= MMU_PAGE_4K
;
106 int mmu_kernel_ssize
= MMU_SEGSIZE_256M
;
107 int mmu_highuser_ssize
= MMU_SEGSIZE_256M
;
108 u16 mmu_slb_size
= 64;
109 EXPORT_SYMBOL_GPL(mmu_slb_size
);
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
->mmu_features
|= MMU_FTR_1T_SEGMENT
;
265 cur_cpu_spec
->mmu_features
&= ~MMU_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
->mmu_features
&= ~(MMU_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
->mmu_features
|= MMU_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
) <= memblock_end_of_DRAM()) {
388 memblock_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 (mmu_has_feature(MMU_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 (mmu_has_feature(MMU_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 memblock_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
= memblock_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 int create_section_mapping(unsigned long start
, unsigned long end
)
538 return 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 #define FUNCTION_TEXT(A) ((*(unsigned long *)(A)))
552 static void __init
htab_finish_init(void)
554 extern unsigned int *htab_call_hpte_insert1
;
555 extern unsigned int *htab_call_hpte_insert2
;
556 extern unsigned int *htab_call_hpte_remove
;
557 extern unsigned int *htab_call_hpte_updatepp
;
559 #ifdef CONFIG_PPC_HAS_HASH_64K
560 extern unsigned int *ht64_call_hpte_insert1
;
561 extern unsigned int *ht64_call_hpte_insert2
;
562 extern unsigned int *ht64_call_hpte_remove
;
563 extern unsigned int *ht64_call_hpte_updatepp
;
565 patch_branch(ht64_call_hpte_insert1
,
566 FUNCTION_TEXT(ppc_md
.hpte_insert
),
568 patch_branch(ht64_call_hpte_insert2
,
569 FUNCTION_TEXT(ppc_md
.hpte_insert
),
571 patch_branch(ht64_call_hpte_remove
,
572 FUNCTION_TEXT(ppc_md
.hpte_remove
),
574 patch_branch(ht64_call_hpte_updatepp
,
575 FUNCTION_TEXT(ppc_md
.hpte_updatepp
),
578 #endif /* CONFIG_PPC_HAS_HASH_64K */
580 patch_branch(htab_call_hpte_insert1
,
581 FUNCTION_TEXT(ppc_md
.hpte_insert
),
583 patch_branch(htab_call_hpte_insert2
,
584 FUNCTION_TEXT(ppc_md
.hpte_insert
),
586 patch_branch(htab_call_hpte_remove
,
587 FUNCTION_TEXT(ppc_md
.hpte_remove
),
589 patch_branch(htab_call_hpte_updatepp
,
590 FUNCTION_TEXT(ppc_md
.hpte_updatepp
),
594 static void __init
htab_initialize(void)
597 unsigned long pteg_count
;
599 unsigned long base
= 0, size
= 0, limit
;
600 struct memblock_region
*reg
;
602 DBG(" -> htab_initialize()\n");
604 /* Initialize segment sizes */
605 htab_init_seg_sizes();
607 /* Initialize page sizes */
608 htab_init_page_sizes();
610 if (mmu_has_feature(MMU_FTR_1T_SEGMENT
)) {
611 mmu_kernel_ssize
= MMU_SEGSIZE_1T
;
612 mmu_highuser_ssize
= MMU_SEGSIZE_1T
;
613 printk(KERN_INFO
"Using 1TB segments\n");
617 * Calculate the required size of the htab. We want the number of
618 * PTEGs to equal one half the number of real pages.
620 htab_size_bytes
= htab_get_table_size();
621 pteg_count
= htab_size_bytes
>> 7;
623 htab_hash_mask
= pteg_count
- 1;
625 if (firmware_has_feature(FW_FEATURE_LPAR
)) {
626 /* Using a hypervisor which owns the htab */
629 #ifdef CONFIG_FA_DUMP
631 * If firmware assisted dump is active firmware preserves
632 * the contents of htab along with entire partition memory.
633 * Clear the htab if firmware assisted dump is active so
634 * that we dont end up using old mappings.
636 if (is_fadump_active() && ppc_md
.hpte_clear_all
)
637 ppc_md
.hpte_clear_all();
640 /* Find storage for the HPT. Must be contiguous in
641 * the absolute address space. On cell we want it to be
642 * in the first 2 Gig so we can use it for IOMMU hacks.
644 if (machine_is(cell
))
647 limit
= MEMBLOCK_ALLOC_ANYWHERE
;
649 table
= memblock_alloc_base(htab_size_bytes
, htab_size_bytes
, limit
);
651 DBG("Hash table allocated at %lx, size: %lx\n", table
,
654 htab_address
= abs_to_virt(table
);
656 /* htab absolute addr + encoded htabsize */
657 _SDR1
= table
+ __ilog2(pteg_count
) - 11;
659 /* Initialize the HPT with no entries */
660 memset((void *)table
, 0, htab_size_bytes
);
663 mtspr(SPRN_SDR1
, _SDR1
);
666 prot
= pgprot_val(PAGE_KERNEL
);
668 #ifdef CONFIG_DEBUG_PAGEALLOC
669 linear_map_hash_count
= memblock_end_of_DRAM() >> PAGE_SHIFT
;
670 linear_map_hash_slots
= __va(memblock_alloc_base(linear_map_hash_count
,
672 memset(linear_map_hash_slots
, 0, linear_map_hash_count
);
673 #endif /* CONFIG_DEBUG_PAGEALLOC */
675 /* On U3 based machines, we need to reserve the DART area and
676 * _NOT_ map it to avoid cache paradoxes as it's remapped non
680 /* create bolted the linear mapping in the hash table */
681 for_each_memblock(memory
, reg
) {
682 base
= (unsigned long)__va(reg
->base
);
685 DBG("creating mapping for region: %lx..%lx (prot: %lx)\n",
688 #ifdef CONFIG_U3_DART
689 /* Do not map the DART space. Fortunately, it will be aligned
690 * in such a way that it will not cross two memblock regions and
691 * will fit within a single 16Mb page.
692 * The DART space is assumed to be a full 16Mb region even if
693 * we only use 2Mb of that space. We will use more of it later
694 * for AGP GART. We have to use a full 16Mb large page.
696 DBG("DART base: %lx\n", dart_tablebase
);
698 if (dart_tablebase
!= 0 && dart_tablebase
>= base
699 && dart_tablebase
< (base
+ size
)) {
700 unsigned long dart_table_end
= dart_tablebase
+ 16 * MB
;
701 if (base
!= dart_tablebase
)
702 BUG_ON(htab_bolt_mapping(base
, dart_tablebase
,
706 if ((base
+ size
) > dart_table_end
)
707 BUG_ON(htab_bolt_mapping(dart_tablebase
+16*MB
,
709 __pa(dart_table_end
),
715 #endif /* CONFIG_U3_DART */
716 BUG_ON(htab_bolt_mapping(base
, base
+ size
, __pa(base
),
717 prot
, mmu_linear_psize
, mmu_kernel_ssize
));
719 memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE
);
722 * If we have a memory_limit and we've allocated TCEs then we need to
723 * explicitly map the TCE area at the top of RAM. We also cope with the
724 * case that the TCEs start below memory_limit.
725 * tce_alloc_start/end are 16MB aligned so the mapping should work
726 * for either 4K or 16MB pages.
728 if (tce_alloc_start
) {
729 tce_alloc_start
= (unsigned long)__va(tce_alloc_start
);
730 tce_alloc_end
= (unsigned long)__va(tce_alloc_end
);
732 if (base
+ size
>= tce_alloc_start
)
733 tce_alloc_start
= base
+ size
+ 1;
735 BUG_ON(htab_bolt_mapping(tce_alloc_start
, tce_alloc_end
,
736 __pa(tce_alloc_start
), prot
,
737 mmu_linear_psize
, mmu_kernel_ssize
));
742 DBG(" <- htab_initialize()\n");
747 void __init
early_init_mmu(void)
749 /* Setup initial STAB address in the PACA */
750 get_paca()->stab_real
= __pa((u64
)&initial_stab
);
751 get_paca()->stab_addr
= (u64
)&initial_stab
;
753 /* Initialize the MMU Hash table and create the linear mapping
754 * of memory. Has to be done before stab/slb initialization as
755 * this is currently where the page size encoding is obtained
759 /* Initialize stab / SLB management */
760 if (mmu_has_feature(MMU_FTR_SLB
))
765 void __cpuinit
early_init_mmu_secondary(void)
767 /* Initialize hash table for that CPU */
768 if (!firmware_has_feature(FW_FEATURE_LPAR
))
769 mtspr(SPRN_SDR1
, _SDR1
);
771 /* Initialize STAB/SLB. We use a virtual address as it works
772 * in real mode on pSeries.
774 if (mmu_has_feature(MMU_FTR_SLB
))
777 stab_initialize(get_paca()->stab_addr
);
779 #endif /* CONFIG_SMP */
782 * Called by asm hashtable.S for doing lazy icache flush
784 unsigned int hash_page_do_lazy_icache(unsigned int pp
, pte_t pte
, int trap
)
788 if (!pfn_valid(pte_pfn(pte
)))
791 page
= pte_page(pte
);
794 if (!test_bit(PG_arch_1
, &page
->flags
) && !PageReserved(page
)) {
796 flush_dcache_icache_page(page
);
797 set_bit(PG_arch_1
, &page
->flags
);
804 #ifdef CONFIG_PPC_MM_SLICES
805 unsigned int get_paca_psize(unsigned long addr
)
807 unsigned long index
, slices
;
809 if (addr
< SLICE_LOW_TOP
) {
810 slices
= get_paca()->context
.low_slices_psize
;
811 index
= GET_LOW_SLICE_INDEX(addr
);
813 slices
= get_paca()->context
.high_slices_psize
;
814 index
= GET_HIGH_SLICE_INDEX(addr
);
816 return (slices
>> (index
* 4)) & 0xF;
820 unsigned int get_paca_psize(unsigned long addr
)
822 return get_paca()->context
.user_psize
;
827 * Demote a segment to using 4k pages.
828 * For now this makes the whole process use 4k pages.
830 #ifdef CONFIG_PPC_64K_PAGES
831 void demote_segment_4k(struct mm_struct
*mm
, unsigned long addr
)
833 if (get_slice_psize(mm
, addr
) == MMU_PAGE_4K
)
835 slice_set_range_psize(mm
, addr
, 1, MMU_PAGE_4K
);
836 #ifdef CONFIG_SPU_BASE
837 spu_flush_all_slbs(mm
);
839 if (get_paca_psize(addr
) != MMU_PAGE_4K
) {
840 get_paca()->context
= mm
->context
;
841 slb_flush_and_rebolt();
844 #endif /* CONFIG_PPC_64K_PAGES */
846 #ifdef CONFIG_PPC_SUBPAGE_PROT
848 * This looks up a 2-bit protection code for a 4k subpage of a 64k page.
849 * Userspace sets the subpage permissions using the subpage_prot system call.
851 * Result is 0: full permissions, _PAGE_RW: read-only,
852 * _PAGE_USER or _PAGE_USER|_PAGE_RW: no access.
854 static int subpage_protection(struct mm_struct
*mm
, unsigned long ea
)
856 struct subpage_prot_table
*spt
= &mm
->context
.spt
;
860 if (ea
>= spt
->maxaddr
)
862 if (ea
< 0x100000000) {
863 /* addresses below 4GB use spt->low_prot */
864 sbpm
= spt
->low_prot
;
866 sbpm
= spt
->protptrs
[ea
>> SBP_L3_SHIFT
];
870 sbpp
= sbpm
[(ea
>> SBP_L2_SHIFT
) & (SBP_L2_COUNT
- 1)];
873 spp
= sbpp
[(ea
>> PAGE_SHIFT
) & (SBP_L1_COUNT
- 1)];
875 /* extract 2-bit bitfield for this 4k subpage */
876 spp
>>= 30 - 2 * ((ea
>> 12) & 0xf);
878 /* turn 0,1,2,3 into combination of _PAGE_USER and _PAGE_RW */
879 spp
= ((spp
& 2) ? _PAGE_USER
: 0) | ((spp
& 1) ? _PAGE_RW
: 0);
883 #else /* CONFIG_PPC_SUBPAGE_PROT */
884 static inline int subpage_protection(struct mm_struct
*mm
, unsigned long ea
)
890 void hash_failure_debug(unsigned long ea
, unsigned long access
,
891 unsigned long vsid
, unsigned long trap
,
892 int ssize
, int psize
, unsigned long pte
)
894 if (!printk_ratelimit())
896 pr_info("mm: Hashing failure ! EA=0x%lx access=0x%lx current=%s\n",
897 ea
, access
, current
->comm
);
898 pr_info(" trap=0x%lx vsid=0x%lx ssize=%d psize=%d pte=0x%lx\n",
899 trap
, vsid
, ssize
, psize
, pte
);
904 * 1 - normal page fault
905 * -1 - critical hash insertion error
906 * -2 - access not permitted by subpage protection mechanism
908 int hash_page(unsigned long ea
, unsigned long access
, unsigned long trap
)
912 struct mm_struct
*mm
;
915 const struct cpumask
*tmp
;
916 int rc
, user_region
= 0, local
= 0;
919 DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n",
922 if ((ea
& ~REGION_MASK
) >= PGTABLE_RANGE
) {
923 DBG_LOW(" out of pgtable range !\n");
927 /* Get region & vsid */
928 switch (REGION_ID(ea
)) {
933 DBG_LOW(" user region with no mm !\n");
936 psize
= get_slice_psize(mm
, ea
);
937 ssize
= user_segment_size(ea
);
938 vsid
= get_vsid(mm
->context
.id
, ea
, ssize
);
940 case VMALLOC_REGION_ID
:
942 vsid
= get_kernel_vsid(ea
, mmu_kernel_ssize
);
943 if (ea
< VMALLOC_END
)
944 psize
= mmu_vmalloc_psize
;
946 psize
= mmu_io_psize
;
947 ssize
= mmu_kernel_ssize
;
951 * Send the problem up to do_page_fault
955 DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm
, mm
->pgd
, vsid
);
962 /* Check CPU locality */
963 tmp
= cpumask_of(smp_processor_id());
964 if (user_region
&& cpumask_equal(mm_cpumask(mm
), tmp
))
967 #ifndef CONFIG_PPC_64K_PAGES
968 /* If we use 4K pages and our psize is not 4K, then we might
969 * be hitting a special driver mapping, and need to align the
970 * address before we fetch the PTE.
972 * It could also be a hugepage mapping, in which case this is
973 * not necessary, but it's not harmful, either.
975 if (psize
!= MMU_PAGE_4K
)
976 ea
&= ~((1ul << mmu_psize_defs
[psize
].shift
) - 1);
977 #endif /* CONFIG_PPC_64K_PAGES */
979 /* Get PTE and page size from page tables */
980 ptep
= find_linux_pte_or_hugepte(pgdir
, ea
, &hugeshift
);
981 if (ptep
== NULL
|| !pte_present(*ptep
)) {
982 DBG_LOW(" no PTE !\n");
986 /* Add _PAGE_PRESENT to the required access perm */
987 access
|= _PAGE_PRESENT
;
989 /* Pre-check access permissions (will be re-checked atomically
990 * in __hash_page_XX but this pre-check is a fast path
992 if (access
& ~pte_val(*ptep
)) {
993 DBG_LOW(" no access !\n");
997 #ifdef CONFIG_HUGETLB_PAGE
999 return __hash_page_huge(ea
, access
, vsid
, ptep
, trap
, local
,
1000 ssize
, hugeshift
, psize
);
1001 #endif /* CONFIG_HUGETLB_PAGE */
1003 #ifndef CONFIG_PPC_64K_PAGES
1004 DBG_LOW(" i-pte: %016lx\n", pte_val(*ptep
));
1006 DBG_LOW(" i-pte: %016lx %016lx\n", pte_val(*ptep
),
1007 pte_val(*(ptep
+ PTRS_PER_PTE
)));
1009 /* Do actual hashing */
1010 #ifdef CONFIG_PPC_64K_PAGES
1011 /* If _PAGE_4K_PFN is set, make sure this is a 4k segment */
1012 if ((pte_val(*ptep
) & _PAGE_4K_PFN
) && psize
== MMU_PAGE_64K
) {
1013 demote_segment_4k(mm
, ea
);
1014 psize
= MMU_PAGE_4K
;
1017 /* If this PTE is non-cacheable and we have restrictions on
1018 * using non cacheable large pages, then we switch to 4k
1020 if (mmu_ci_restrictions
&& psize
== MMU_PAGE_64K
&&
1021 (pte_val(*ptep
) & _PAGE_NO_CACHE
)) {
1023 demote_segment_4k(mm
, ea
);
1024 psize
= MMU_PAGE_4K
;
1025 } else if (ea
< VMALLOC_END
) {
1027 * some driver did a non-cacheable mapping
1028 * in vmalloc space, so switch vmalloc
1031 printk(KERN_ALERT
"Reducing vmalloc segment "
1032 "to 4kB pages because of "
1033 "non-cacheable mapping\n");
1034 psize
= mmu_vmalloc_psize
= MMU_PAGE_4K
;
1035 #ifdef CONFIG_SPU_BASE
1036 spu_flush_all_slbs(mm
);
1041 if (psize
!= get_paca_psize(ea
)) {
1042 get_paca()->context
= mm
->context
;
1043 slb_flush_and_rebolt();
1045 } else if (get_paca()->vmalloc_sllp
!=
1046 mmu_psize_defs
[mmu_vmalloc_psize
].sllp
) {
1047 get_paca()->vmalloc_sllp
=
1048 mmu_psize_defs
[mmu_vmalloc_psize
].sllp
;
1049 slb_vmalloc_update();
1051 #endif /* CONFIG_PPC_64K_PAGES */
1053 #ifdef CONFIG_PPC_HAS_HASH_64K
1054 if (psize
== MMU_PAGE_64K
)
1055 rc
= __hash_page_64K(ea
, access
, vsid
, ptep
, trap
, local
, ssize
);
1057 #endif /* CONFIG_PPC_HAS_HASH_64K */
1059 int spp
= subpage_protection(mm
, ea
);
1063 rc
= __hash_page_4K(ea
, access
, vsid
, ptep
, trap
,
1067 /* Dump some info in case of hash insertion failure, they should
1068 * never happen so it is really useful to know if/when they do
1071 hash_failure_debug(ea
, access
, vsid
, trap
, ssize
, psize
,
1073 #ifndef CONFIG_PPC_64K_PAGES
1074 DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep
));
1076 DBG_LOW(" o-pte: %016lx %016lx\n", pte_val(*ptep
),
1077 pte_val(*(ptep
+ PTRS_PER_PTE
)));
1079 DBG_LOW(" -> rc=%d\n", rc
);
1082 EXPORT_SYMBOL_GPL(hash_page
);
1084 void hash_preload(struct mm_struct
*mm
, unsigned long ea
,
1085 unsigned long access
, unsigned long trap
)
1090 unsigned long flags
;
1091 int rc
, ssize
, local
= 0;
1093 BUG_ON(REGION_ID(ea
) != USER_REGION_ID
);
1095 #ifdef CONFIG_PPC_MM_SLICES
1096 /* We only prefault standard pages for now */
1097 if (unlikely(get_slice_psize(mm
, ea
) != mm
->context
.user_psize
))
1101 DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx,"
1102 " trap=%lx\n", mm
, mm
->pgd
, ea
, access
, trap
);
1104 /* Get Linux PTE if available */
1108 ptep
= find_linux_pte(pgdir
, ea
);
1112 #ifdef CONFIG_PPC_64K_PAGES
1113 /* If either _PAGE_4K_PFN or _PAGE_NO_CACHE is set (and we are on
1114 * a 64K kernel), then we don't preload, hash_page() will take
1115 * care of it once we actually try to access the page.
1116 * That way we don't have to duplicate all of the logic for segment
1117 * page size demotion here
1119 if (pte_val(*ptep
) & (_PAGE_4K_PFN
| _PAGE_NO_CACHE
))
1121 #endif /* CONFIG_PPC_64K_PAGES */
1124 ssize
= user_segment_size(ea
);
1125 vsid
= get_vsid(mm
->context
.id
, ea
, ssize
);
1127 /* Hash doesn't like irqs */
1128 local_irq_save(flags
);
1130 /* Is that local to this CPU ? */
1131 if (cpumask_equal(mm_cpumask(mm
), cpumask_of(smp_processor_id())))
1135 #ifdef CONFIG_PPC_HAS_HASH_64K
1136 if (mm
->context
.user_psize
== MMU_PAGE_64K
)
1137 rc
= __hash_page_64K(ea
, access
, vsid
, ptep
, trap
, local
, ssize
);
1139 #endif /* CONFIG_PPC_HAS_HASH_64K */
1140 rc
= __hash_page_4K(ea
, access
, vsid
, ptep
, trap
, local
, ssize
,
1141 subpage_protection(mm
, ea
));
1143 /* Dump some info in case of hash insertion failure, they should
1144 * never happen so it is really useful to know if/when they do
1147 hash_failure_debug(ea
, access
, vsid
, trap
, ssize
,
1148 mm
->context
.user_psize
, pte_val(*ptep
));
1150 local_irq_restore(flags
);
1153 /* WARNING: This is called from hash_low_64.S, if you change this prototype,
1154 * do not forget to update the assembly call site !
1156 void flush_hash_page(unsigned long va
, real_pte_t pte
, int psize
, int ssize
,
1159 unsigned long hash
, index
, shift
, hidx
, slot
;
1161 DBG_LOW("flush_hash_page(va=%016lx)\n", va
);
1162 pte_iterate_hashed_subpages(pte
, psize
, va
, index
, shift
) {
1163 hash
= hpt_hash(va
, shift
, ssize
);
1164 hidx
= __rpte_to_hidx(pte
, index
);
1165 if (hidx
& _PTEIDX_SECONDARY
)
1167 slot
= (hash
& htab_hash_mask
) * HPTES_PER_GROUP
;
1168 slot
+= hidx
& _PTEIDX_GROUP_IX
;
1169 DBG_LOW(" sub %ld: hash=%lx, hidx=%lx\n", index
, slot
, hidx
);
1170 ppc_md
.hpte_invalidate(slot
, va
, psize
, ssize
, local
);
1171 } pte_iterate_hashed_end();
1174 void flush_hash_range(unsigned long number
, int local
)
1176 if (ppc_md
.flush_hash_range
)
1177 ppc_md
.flush_hash_range(number
, local
);
1180 struct ppc64_tlb_batch
*batch
=
1181 &__get_cpu_var(ppc64_tlb_batch
);
1183 for (i
= 0; i
< number
; i
++)
1184 flush_hash_page(batch
->vaddr
[i
], batch
->pte
[i
],
1185 batch
->psize
, batch
->ssize
, local
);
1190 * low_hash_fault is called when we the low level hash code failed
1191 * to instert a PTE due to an hypervisor error
1193 void low_hash_fault(struct pt_regs
*regs
, unsigned long address
, int rc
)
1195 if (user_mode(regs
)) {
1196 #ifdef CONFIG_PPC_SUBPAGE_PROT
1198 _exception(SIGSEGV
, regs
, SEGV_ACCERR
, address
);
1201 _exception(SIGBUS
, regs
, BUS_ADRERR
, address
);
1203 bad_page_fault(regs
, address
, SIGBUS
);
1206 #ifdef CONFIG_DEBUG_PAGEALLOC
1207 static void kernel_map_linear_page(unsigned long vaddr
, unsigned long lmi
)
1209 unsigned long hash
, hpteg
;
1210 unsigned long vsid
= get_kernel_vsid(vaddr
, mmu_kernel_ssize
);
1211 unsigned long va
= hpt_va(vaddr
, vsid
, mmu_kernel_ssize
);
1212 unsigned long mode
= htab_convert_pte_flags(PAGE_KERNEL
);
1215 hash
= hpt_hash(va
, PAGE_SHIFT
, mmu_kernel_ssize
);
1216 hpteg
= ((hash
& htab_hash_mask
) * HPTES_PER_GROUP
);
1218 ret
= ppc_md
.hpte_insert(hpteg
, va
, __pa(vaddr
),
1219 mode
, HPTE_V_BOLTED
,
1220 mmu_linear_psize
, mmu_kernel_ssize
);
1222 spin_lock(&linear_map_hash_lock
);
1223 BUG_ON(linear_map_hash_slots
[lmi
] & 0x80);
1224 linear_map_hash_slots
[lmi
] = ret
| 0x80;
1225 spin_unlock(&linear_map_hash_lock
);
1228 static void kernel_unmap_linear_page(unsigned long vaddr
, unsigned long lmi
)
1230 unsigned long hash
, hidx
, slot
;
1231 unsigned long vsid
= get_kernel_vsid(vaddr
, mmu_kernel_ssize
);
1232 unsigned long va
= hpt_va(vaddr
, vsid
, mmu_kernel_ssize
);
1234 hash
= hpt_hash(va
, PAGE_SHIFT
, mmu_kernel_ssize
);
1235 spin_lock(&linear_map_hash_lock
);
1236 BUG_ON(!(linear_map_hash_slots
[lmi
] & 0x80));
1237 hidx
= linear_map_hash_slots
[lmi
] & 0x7f;
1238 linear_map_hash_slots
[lmi
] = 0;
1239 spin_unlock(&linear_map_hash_lock
);
1240 if (hidx
& _PTEIDX_SECONDARY
)
1242 slot
= (hash
& htab_hash_mask
) * HPTES_PER_GROUP
;
1243 slot
+= hidx
& _PTEIDX_GROUP_IX
;
1244 ppc_md
.hpte_invalidate(slot
, va
, mmu_linear_psize
, mmu_kernel_ssize
, 0);
1247 void kernel_map_pages(struct page
*page
, int numpages
, int enable
)
1249 unsigned long flags
, vaddr
, lmi
;
1252 local_irq_save(flags
);
1253 for (i
= 0; i
< numpages
; i
++, page
++) {
1254 vaddr
= (unsigned long)page_address(page
);
1255 lmi
= __pa(vaddr
) >> PAGE_SHIFT
;
1256 if (lmi
>= linear_map_hash_count
)
1259 kernel_map_linear_page(vaddr
, lmi
);
1261 kernel_unmap_linear_page(vaddr
, lmi
);
1263 local_irq_restore(flags
);
1265 #endif /* CONFIG_DEBUG_PAGEALLOC */
1267 void setup_initial_memory_limit(phys_addr_t first_memblock_base
,
1268 phys_addr_t first_memblock_size
)
1270 /* We don't currently support the first MEMBLOCK not mapping 0
1271 * physical on those processors
1273 BUG_ON(first_memblock_base
!= 0);
1275 /* On LPAR systems, the first entry is our RMA region,
1276 * non-LPAR 64-bit hash MMU systems don't have a limitation
1277 * on real mode access, but using the first entry works well
1278 * enough. We also clamp it to 1G to avoid some funky things
1279 * such as RTAS bugs etc...
1281 ppc64_rma_size
= min_t(u64
, first_memblock_size
, 0x40000000);
1283 /* Finally limit subsequent allocations */
1284 memblock_set_current_limit(ppc64_rma_size
);