~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/arch/powerpc/mm/hugetlbpage-hash64.c

Version: ~ [ linux-5.9-rc6 ] ~ [ linux-5.8.10 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.66 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.146 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.198 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.236 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.236 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.85 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 // SPDX-License-Identifier: GPL-2.0
  2 /*
  3  * PPC64 Huge TLB Page Support for hash based MMUs (POWER4 and later)
  4  *
  5  * Copyright (C) 2003 David Gibson, IBM Corporation.
  6  *
  7  * Based on the IA-32 version:
  8  * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
  9  */
 10 
 11 #include <linux/mm.h>
 12 #include <linux/hugetlb.h>
 13 #include <asm/pgtable.h>
 14 #include <asm/pgalloc.h>
 15 #include <asm/cacheflush.h>
 16 #include <asm/machdep.h>
 17 
 18 extern long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
 19                                   unsigned long pa, unsigned long rlags,
 20                                   unsigned long vflags, int psize, int ssize);
 21 
 22 int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
 23                      pte_t *ptep, unsigned long trap, unsigned long flags,
 24                      int ssize, unsigned int shift, unsigned int mmu_psize)
 25 {
 26         real_pte_t rpte;
 27         unsigned long vpn;
 28         unsigned long old_pte, new_pte;
 29         unsigned long rflags, pa, sz;
 30         long slot, offset;
 31 
 32         BUG_ON(shift != mmu_psize_defs[mmu_psize].shift);
 33 
 34         /* Search the Linux page table for a match with va */
 35         vpn = hpt_vpn(ea, vsid, ssize);
 36 
 37         /* At this point, we have a pte (old_pte) which can be used to build
 38          * or update an HPTE. There are 2 cases:
 39          *
 40          * 1. There is a valid (present) pte with no associated HPTE (this is
 41          *      the most common case)
 42          * 2. There is a valid (present) pte with an associated HPTE. The
 43          *      current values of the pp bits in the HPTE prevent access
 44          *      because we are doing software DIRTY bit management and the
 45          *      page is currently not DIRTY.
 46          */
 47 
 48 
 49         do {
 50                 old_pte = pte_val(*ptep);
 51                 /* If PTE busy, retry the access */
 52                 if (unlikely(old_pte & H_PAGE_BUSY))
 53                         return 0;
 54                 /* If PTE permissions don't match, take page fault */
 55                 if (unlikely(!check_pte_access(access, old_pte)))
 56                         return 1;
 57 
 58                 /* Try to lock the PTE, add ACCESSED and DIRTY if it was
 59                  * a write access */
 60                 new_pte = old_pte | H_PAGE_BUSY | _PAGE_ACCESSED;
 61                 if (access & _PAGE_WRITE)
 62                         new_pte |= _PAGE_DIRTY;
 63         } while(!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
 64 
 65         rflags = htab_convert_pte_flags(new_pte);
 66         if (unlikely(mmu_psize == MMU_PAGE_16G))
 67                 offset = PTRS_PER_PUD;
 68         else
 69                 offset = PTRS_PER_PMD;
 70         rpte = __real_pte(__pte(old_pte), ptep, offset);
 71 
 72         sz = ((1UL) << shift);
 73         if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
 74                 /* No CPU has hugepages but lacks no execute, so we
 75                  * don't need to worry about that case */
 76                 rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap);
 77 
 78         /* Check if pte already has an hpte (case 2) */
 79         if (unlikely(old_pte & H_PAGE_HASHPTE)) {
 80                 /* There MIGHT be an HPTE for this pte */
 81                 unsigned long gslot;
 82 
 83                 gslot = pte_get_hash_gslot(vpn, shift, ssize, rpte, 0);
 84                 if (mmu_hash_ops.hpte_updatepp(gslot, rflags, vpn, mmu_psize,
 85                                                mmu_psize, ssize, flags) == -1)
 86                         old_pte &= ~_PAGE_HPTEFLAGS;
 87         }
 88 
 89         if (likely(!(old_pte & H_PAGE_HASHPTE))) {
 90                 unsigned long hash = hpt_hash(vpn, shift, ssize);
 91 
 92                 pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
 93 
 94                 /* clear HPTE slot informations in new PTE */
 95                 new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | H_PAGE_HASHPTE;
 96 
 97                 slot = hpte_insert_repeating(hash, vpn, pa, rflags, 0,
 98                                              mmu_psize, ssize);
 99 
100                 /*
101                  * Hypervisor failure. Restore old pte and return -1
102                  * similar to __hash_page_*
103                  */
104                 if (unlikely(slot == -2)) {
105                         *ptep = __pte(old_pte);
106                         hash_failure_debug(ea, access, vsid, trap, ssize,
107                                            mmu_psize, mmu_psize, old_pte);
108                         return -1;
109                 }
110 
111                 new_pte |= pte_set_hidx(ptep, rpte, 0, slot, offset);
112         }
113 
114         /*
115          * No need to use ldarx/stdcx here
116          */
117         *ptep = __pte(new_pte & ~H_PAGE_BUSY);
118         return 0;
119 }
120 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp