 83d5e64b7e
			
		
	
	
	83d5e64b7e
	
	
	
		
			
			Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
		
			
				
	
	
		
			81 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
	
		
			3.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /* To be include by pgtable-hash64.h only */
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| 
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| /* Additional PTE bits (don't change without checking asm in hash_low.S) */
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| #define _PAGE_SPECIAL	0x00000400 /* software: special page */
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| #define _PAGE_HPTE_SUB	0x0ffff000 /* combo only: sub pages HPTE bits */
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| #define _PAGE_HPTE_SUB0	0x08000000 /* combo only: first sub page */
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| #define _PAGE_COMBO	0x10000000 /* this is a combo 4k page */
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| #define _PAGE_4K_PFN	0x20000000 /* PFN is for a single 4k page */
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| 
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| /* For 64K page, we don't have a separate _PAGE_HASHPTE bit. Instead,
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|  * we set that to be the whole sub-bits mask. The C code will only
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|  * test this, so a multi-bit mask will work. For combo pages, this
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|  * is equivalent as effectively, the old _PAGE_HASHPTE was an OR of
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|  * all the sub bits. For real 64k pages, we now have the assembly set
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|  * _PAGE_HPTE_SUB0 in addition to setting the HIDX bits which overlap
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|  * that mask. This is fine as long as the HIDX bits are never set on
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|  * a PTE that isn't hashed, which is the case today.
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|  *
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|  * A little nit is for the huge page C code, which does the hashing
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|  * in C, we need to provide which bit to use.
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|  */
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| #define _PAGE_HASHPTE	_PAGE_HPTE_SUB
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| 
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| /* Note the full page bits must be in the same location as for normal
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|  * 4k pages as the same assembly will be used to insert 64K pages
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|  * whether the kernel has CONFIG_PPC_64K_PAGES or not
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|  */
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| #define _PAGE_F_SECOND  0x00008000 /* full page: hidx bits */
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| #define _PAGE_F_GIX     0x00007000 /* full page: hidx bits */
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| 
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| /* PTE flags to conserve for HPTE identification */
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| #define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_COMBO)
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| 
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| /* Shift to put page number into pte.
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|  *
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|  * That gives us a max RPN of 34 bits, which means a max of 50 bits
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|  * of addressable physical space, or 46 bits for the special 4k PFNs.
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|  */
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| #define PTE_RPN_SHIFT	(30)
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| 
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| #ifndef __ASSEMBLY__
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| 
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| /*
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|  * With 64K pages on hash table, we have a special PTE format that
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|  * uses a second "half" of the page table to encode sub-page information
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|  * in order to deal with 64K made of 4K HW pages. Thus we override the
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|  * generic accessors and iterators here
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|  */
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| #define __real_pte(e,p) 	((real_pte_t) { \
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| 			(e), (pte_val(e) & _PAGE_COMBO) ? \
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| 				(pte_val(*((p) + PTRS_PER_PTE))) : 0 })
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| #define __rpte_to_hidx(r,index)	((pte_val((r).pte) & _PAGE_COMBO) ? \
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|         (((r).hidx >> ((index)<<2)) & 0xf) : ((pte_val((r).pte) >> 12) & 0xf))
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| #define __rpte_to_pte(r)	((r).pte)
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| #define __rpte_sub_valid(rpte, index) \
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| 	(pte_val(rpte.pte) & (_PAGE_HPTE_SUB0 >> (index)))
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| 
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| /* Trick: we set __end to va + 64k, which happens works for
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|  * a 16M page as well as we want only one iteration
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|  */
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| #define pte_iterate_hashed_subpages(rpte, psize, vpn, index, shift)	\
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| 	do {								\
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| 		unsigned long __end = vpn + (1UL << (PAGE_SHIFT - VPN_SHIFT));	\
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| 		unsigned __split = (psize == MMU_PAGE_4K ||		\
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| 				    psize == MMU_PAGE_64K_AP);		\
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| 		shift = mmu_psize_defs[psize].shift;			\
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| 		for (index = 0; vpn < __end; index++,			\
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| 			     vpn += (1L << (shift - VPN_SHIFT))) {	\
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| 			if (!__split || __rpte_sub_valid(rpte, index))	\
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| 				do {
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| 
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| #define pte_iterate_hashed_end() } while(0); } } while(0)
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| 
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| #define pte_pagesize_index(mm, addr, pte)	\
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| 	(((pte) & _PAGE_COMBO)? MMU_PAGE_4K: MMU_PAGE_64K)
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| 
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| #define remap_4k_pfn(vma, addr, pfn, prot)				\
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| 	remap_pfn_range((vma), (addr), (pfn), PAGE_SIZE,		\
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| 			__pgprot(pgprot_val((prot)) | _PAGE_4K_PFN))
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| 
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| #endif	/* __ASSEMBLY__ */
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