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Release 4.10 arch/powerpc/mm/hugetlbpage-hash64.c

Directory: arch/powerpc/mm
/*
 * PPC64 Huge TLB Page Support for hash based MMUs (POWER4 and later)
 *
 * Copyright (C) 2003 David Gibson, IBM Corporation.
 *
 * Based on the IA-32 version:
 * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
 */

#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/cacheflush.h>
#include <asm/machdep.h>

extern long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
				  unsigned long pa, unsigned long rlags,
				  unsigned long vflags, int psize, int ssize);


int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid, pte_t *ptep, unsigned long trap, unsigned long flags, int ssize, unsigned int shift, unsigned int mmu_psize) { unsigned long vpn; unsigned long old_pte, new_pte; unsigned long rflags, pa, sz; long slot; BUG_ON(shift != mmu_psize_defs[mmu_psize].shift); /* Search the Linux page table for a match with va */ vpn = hpt_vpn(ea, vsid, ssize); /* At this point, we have a pte (old_pte) which can be used to build * or update an HPTE. There are 2 cases: * * 1. There is a valid (present) pte with no associated HPTE (this is * the most common case) * 2. There is a valid (present) pte with an associated HPTE. The * current values of the pp bits in the HPTE prevent access * because we are doing software DIRTY bit management and the * page is currently not DIRTY. */ do { old_pte = pte_val(*ptep); /* If PTE busy, retry the access */ if (unlikely(old_pte & H_PAGE_BUSY)) return 0; /* If PTE permissions don't match, take page fault */ if (unlikely(!check_pte_access(access, old_pte))) return 1; /* Try to lock the PTE, add ACCESSED and DIRTY if it was * a write access */ new_pte = old_pte | H_PAGE_BUSY | _PAGE_ACCESSED; if (access & _PAGE_WRITE) new_pte |= _PAGE_DIRTY; } while(!pte_xchg(ptep, __pte(old_pte), __pte(new_pte))); rflags = htab_convert_pte_flags(new_pte); sz = ((1UL) << shift); if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) /* No CPU has hugepages but lacks no execute, so we * don't need to worry about that case */ rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap); /* Check if pte already has an hpte (case 2) */ if (unlikely(old_pte & H_PAGE_HASHPTE)) { /* There MIGHT be an HPTE for this pte */ unsigned long hash, slot; hash = hpt_hash(vpn, shift, ssize); if (old_pte & H_PAGE_F_SECOND) hash = ~hash; slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; slot += (old_pte & H_PAGE_F_GIX) >> H_PAGE_F_GIX_SHIFT; if (mmu_hash_ops.hpte_updatepp(slot, rflags, vpn, mmu_psize, mmu_psize, ssize, flags) == -1) old_pte &= ~_PAGE_HPTEFLAGS; } if (likely(!(old_pte & H_PAGE_HASHPTE))) { unsigned long hash = hpt_hash(vpn, shift, ssize); pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT; /* clear HPTE slot informations in new PTE */ new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | H_PAGE_HASHPTE; slot = hpte_insert_repeating(hash, vpn, pa, rflags, 0, mmu_psize, ssize); /* * Hypervisor failure. Restore old pte and return -1 * similar to __hash_page_* */ if (unlikely(slot == -2)) { *ptep = __pte(old_pte); hash_failure_debug(ea, access, vsid, trap, ssize, mmu_psize, mmu_psize, old_pte); return -1; } new_pte |= (slot << H_PAGE_F_GIX_SHIFT) & (H_PAGE_F_SECOND | H_PAGE_F_GIX); } /* * No need to use ldarx/stdcx here */ *ptep = __pte(new_pte & ~H_PAGE_BUSY); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
david gibsondavid gibson32874.89%212.50%
benjamin herrenschmidtbenjamin herrenschmidt5111.64%318.75%
aneesh kumaraneesh kumar398.90%850.00%
anton blanchardanton blanchard102.28%16.25%
michael ellermanmichael ellerman81.83%16.25%
li zhongli zhong20.46%16.25%
Total438100.00%16100.00%

#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_DEBUG_VM) /* * This enables us to catch the wrong page directory format * Moved here so that we can use WARN() in the call. */
int hugepd_ok(hugepd_t hpd) { bool is_hugepd; unsigned long hpdval; hpdval = hpd_val(hpd); /* * We should not find this format in page directory, warn otherwise. */ is_hugepd = (((hpdval & 0x3) == 0x0) && ((hpdval & HUGEPD_SHIFT_MASK) != 0)); WARN(is_hugepd, "Found wrong page directory format\n"); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
aneesh kumaraneesh kumar57100.00%2100.00%
Total57100.00%2100.00%

#endif

Overall Contributors

PersonTokensPropCommitsCommitProp
david gibsondavid gibson34762.08%211.11%
aneesh kumaraneesh kumar11019.68%1055.56%
benjamin herrenschmidtbenjamin herrenschmidt519.12%316.67%
li zhongli zhong335.90%15.56%
anton blanchardanton blanchard101.79%15.56%
michael ellermanmichael ellerman81.43%15.56%
Total559100.00%18100.00%
Directory: arch/powerpc/mm
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