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Release 4.16 arch/powerpc/include/asm/book3s/64/hash-64k.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_BOOK3S_64_HASH_64K_H

#define _ASM_POWERPC_BOOK3S_64_HASH_64K_H


#define H_PTE_INDEX_SIZE  8

#define H_PMD_INDEX_SIZE  10

#define H_PUD_INDEX_SIZE  7

#define H_PGD_INDEX_SIZE  8

/*
 * 64k aligned address free up few of the lower bits of RPN for us
 * We steal that here. For more deatils look at pte_pfn/pfn_pte()
 */

#define H_PAGE_COMBO	_RPAGE_RPN0 
/* this is a combo 4k page */

#define H_PAGE_4K_PFN	_RPAGE_RPN1 
/* PFN is for a single 4k page */

#define H_PAGE_BUSY	_RPAGE_RPN44     
/* software: PTE & hash are busy */

#define H_PAGE_HASHPTE	_RPAGE_RPN43	
/* PTE has associated HPTE */

/*
 * We need to differentiate between explicit huge page and THP huge
 * page, since THP huge page also need to track real subpage details
 */

#define H_PAGE_THP_HUGE  H_PAGE_4K_PFN

/* PTE flags to conserve for HPTE identification */

#define _PAGE_HPTEFLAGS (H_PAGE_BUSY | H_PAGE_HASHPTE | H_PAGE_COMBO)
/*
 * we support 16 fragments per PTE page of 64K size.
 */

#define H_PTE_FRAG_NR	16
/*
 * We use a 2K PTE page fragment and another 2K for storing
 * real_pte_t hash index
 */

#define H_PTE_FRAG_SIZE_SHIFT  12

#define PTE_FRAG_SIZE (1UL << PTE_FRAG_SIZE_SHIFT)

#ifndef __ASSEMBLY__
#include <asm/errno.h>

/*
 * With 64K pages on hash table, we have a special PTE format that
 * uses a second "half" of the page table to encode sub-page information
 * in order to deal with 64K made of 4K HW pages. Thus we override the
 * generic accessors and iterators here
 */

#define __real_pte __real_pte

static inline real_pte_t __real_pte(pte_t pte, pte_t *ptep, int offset) { real_pte_t rpte; unsigned long *hidxp; rpte.pte = pte; /* * Ensure that we do not read the hidx before we read the PTE. Because * the writer side is expected to finish writing the hidx first followed * by the PTE, by using smp_wmb(). pte_set_hash_slot() ensures that. */ smp_rmb(); hidxp = (unsigned long *)(ptep + offset); rpte.hidx = *hidxp; return rpte; }

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Aneesh Kumar K.V5493.10%360.00%
Benjamin Herrenschmidt35.17%120.00%
Ram Pai11.72%120.00%
Total58100.00%5100.00%

/* * shift the hidx representation by one-modulo-0xf; i.e hidx 0 is respresented * as 1, 1 as 2,... , and 0xf as 0. This convention lets us represent a * invalid hidx 0xf with a 0x0 bit value. PTEs are anyway zero'd when * allocated. We dont have to zero them gain; thus save on the initialization. */ #define HIDX_UNSHIFT_BY_ONE(x) ((x + 0xfUL) & 0xfUL) /* shift backward by one */ #define HIDX_SHIFT_BY_ONE(x) ((x + 0x1UL) & 0xfUL) /* shift forward by one */ #define HIDX_BITS(x, index) (x << (index << 2)) #define BITS_TO_HIDX(x, index) ((x >> (index << 2)) & 0xfUL) #define INVALID_RPTE_HIDX 0x0UL
static inline unsigned long __rpte_to_hidx(real_pte_t rpte, unsigned long index) { return HIDX_UNSHIFT_BY_ONE(BITS_TO_HIDX(rpte.hidx, index)); }

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Aneesh Kumar K.V1864.29%125.00%
Ram Pai517.86%250.00%
Benjamin Herrenschmidt517.86%125.00%
Total28100.00%4100.00%

/* * Commit the hidx and return PTE bits that needs to be modified. The caller is * expected to modify the PTE bits accordingly and commit the PTE to memory. */
static inline unsigned long pte_set_hidx(pte_t *ptep, real_pte_t rpte, unsigned int subpg_index, unsigned long hidx, int offset) { unsigned long *hidxp = (unsigned long *)(ptep + offset); rpte.hidx &= ~HIDX_BITS(0xfUL, subpg_index); *hidxp = rpte.hidx | HIDX_BITS(HIDX_SHIFT_BY_ONE(hidx), subpg_index); /* * Anyone reading PTE must ensure hidx bits are read after reading the * PTE by using the read-side barrier smp_rmb(). __real_pte() can be * used for that. */ smp_wmb(); /* No PTE bits to be modified, return 0x0UL */ return 0x0UL; }

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Ram Pai6481.01%250.00%
Aneesh Kumar K.V1518.99%250.00%
Total79100.00%4100.00%

#define __rpte_to_pte(r) ((r).pte) extern bool __rpte_sub_valid(real_pte_t rpte, unsigned long index); /* * Trick: we set __end to va + 64k, which happens works for * a 16M page as well as we want only one iteration */ #define pte_iterate_hashed_subpages(rpte, psize, vpn, index, shift) \ do { \ unsigned long __end = vpn + (1UL << (PAGE_SHIFT - VPN_SHIFT)); \ unsigned __split = (psize == MMU_PAGE_4K || \ psize == MMU_PAGE_64K_AP); \ shift = mmu_psize_defs[psize].shift; \ for (index = 0; vpn < __end; index++, \ vpn += (1L << (shift - VPN_SHIFT))) { \ if (!__split || __rpte_sub_valid(rpte, index)) \ do { #define pte_iterate_hashed_end() } while(0); } } while(0) #define pte_pagesize_index(mm, addr, pte) \ (((pte) & H_PAGE_COMBO)? MMU_PAGE_4K: MMU_PAGE_64K) extern int remap_pfn_range(struct vm_area_struct *, unsigned long addr, unsigned long pfn, unsigned long size, pgprot_t);
static inline int hash__remap_4k_pfn(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, pgprot_t prot) { if (pfn > (PTE_RPN_MASK >> PAGE_SHIFT)) { WARN(1, "remap_4k_pfn called with wrong pfn value\n"); return -EINVAL; } return remap_pfn_range(vma, addr, pfn, PAGE_SIZE, __pgprot(pgprot_val(prot) | H_PAGE_4K_PFN)); }

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Aneesh Kumar K.V5986.76%375.00%
Paul Mackerras913.24%125.00%
Total68100.00%4100.00%

#define H_PTE_TABLE_SIZE PTE_FRAG_SIZE #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined (CONFIG_HUGETLB_PAGE) #define H_PMD_TABLE_SIZE ((sizeof(pmd_t) << PMD_INDEX_SIZE) + \ (sizeof(unsigned long) << PMD_INDEX_SIZE)) #else #define H_PMD_TABLE_SIZE (sizeof(pmd_t) << PMD_INDEX_SIZE) #endif #ifdef CONFIG_HUGETLB_PAGE #define H_PUD_TABLE_SIZE ((sizeof(pud_t) << PUD_INDEX_SIZE) + \ (sizeof(unsigned long) << PUD_INDEX_SIZE)) #else #define H_PUD_TABLE_SIZE (sizeof(pud_t) << PUD_INDEX_SIZE) #endif #define H_PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE) #ifdef CONFIG_TRANSPARENT_HUGEPAGE
static inline char *get_hpte_slot_array(pmd_t *pmdp) { /* * The hpte hindex is stored in the pgtable whose address is in the * second half of the PMD * * Order this load with the test for pmd_trans_huge in the caller */ smp_rmb(); return *(char **)(pmdp + PTRS_PER_PMD); }

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Aneesh Kumar K.V29100.00%1100.00%
Total29100.00%1100.00%

/* * The linux hugepage PMD now include the pmd entries followed by the address * to the stashed pgtable_t. The stashed pgtable_t contains the hpte bits. * [ 000 | 1 bit secondary | 3 bit hidx | 1 bit valid]. We use one byte per * each HPTE entry. With 16MB hugepage and 64K HPTE we need 256 entries and * with 4K HPTE we need 4096 entries. Both will fit in a 4K pgtable_t. * * The top three bits are intentionally left as zero. This memory location * are also used as normal page PTE pointers. So if we have any pointers * left around while we collapse a hugepage, we need to make sure * _PAGE_PRESENT bit of that is zero when we look at them */
static inline unsigned int hpte_valid(unsigned char *hpte_slot_array, int index) { return hpte_slot_array[index] & 0x1; }

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Aneesh Kumar K.V24100.00%1100.00%
Total24100.00%1100.00%


static inline unsigned int hpte_hash_index(unsigned char *hpte_slot_array, int index) { return hpte_slot_array[index] >> 1; }

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Aneesh Kumar K.V2395.83%150.00%
Paul Mackerras14.17%150.00%
Total24100.00%2100.00%


static inline void mark_hpte_slot_valid(unsigned char *hpte_slot_array, unsigned int index, unsigned int hidx) { hpte_slot_array[index] = (hidx << 1) | 0x1; }

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Aneesh Kumar K.V3090.91%150.00%
Paul Mackerras39.09%150.00%
Total33100.00%2100.00%

/* * * For core kernel code by design pmd_trans_huge is never run on any hugetlbfs * page. The hugetlbfs page table walking and mangling paths are totally * separated form the core VM paths and they're differentiated by * VM_HUGETLB being set on vm_flags well before any pmd_trans_huge could run. * * pmd_trans_huge() is defined as false at build time if * CONFIG_TRANSPARENT_HUGEPAGE=n to optimize away code blocks at build * time in such case. * * For ppc64 we need to differntiate from explicit hugepages from THP, because * for THP we also track the subpage details at the pmd level. We don't do * that for explicit huge pages. * */
static inline int hash__pmd_trans_huge(pmd_t pmd) { return !!((pmd_val(pmd) & (_PAGE_PTE | H_PAGE_THP_HUGE)) == (_PAGE_PTE | H_PAGE_THP_HUGE)); }

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Aneesh Kumar K.V34100.00%4100.00%
Total34100.00%4100.00%


static inline int hash__pmd_same(pmd_t pmd_a, pmd_t pmd_b) { return (((pmd_raw(pmd_a) ^ pmd_raw(pmd_b)) & ~cpu_to_be64(_PAGE_HPTEFLAGS)) == 0); }

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Aneesh Kumar K.V3386.84%266.67%
Michael Ellerman513.16%133.33%
Total38100.00%3100.00%


static inline pmd_t hash__pmd_mkhuge(pmd_t pmd) { return __pmd(pmd_val(pmd) | (_PAGE_PTE | H_PAGE_THP_HUGE)); }

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Aneesh Kumar K.V25100.00%1100.00%
Total25100.00%1100.00%

extern unsigned long hash__pmd_hugepage_update(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, unsigned long clr, unsigned long set); extern pmd_t hash__pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp); extern void hash__pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, pgtable_t pgtable); extern pgtable_t hash__pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp); extern pmd_t hash__pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp); extern int hash__has_transparent_hugepage(void); #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ #endif /* __ASSEMBLY__ */ #endif /* _ASM_POWERPC_BOOK3S_64_HASH_64K_H */

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Aneesh Kumar K.V58373.24%2158.33%
Ram Pai12015.08%513.89%
Benjamin Herrenschmidt607.54%411.11%
Paul Mackerras243.02%38.33%
Michael Ellerman81.01%25.56%
Greg Kroah-Hartman10.13%12.78%
Total796100.00%36100.00%
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