mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 06:56:52 +07:00
9859f0c7e0
We don't do this for other page table entries. So lets keep this simple and always return false for hugepd check on a 64K page size config. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
119 lines
3.4 KiB
C
119 lines
3.4 KiB
C
/*
|
|
* 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;
|
|
}
|