327 lines
9.0 KiB
C
327 lines
9.0 KiB
C
/*
|
|
* Copyright IBM Corporation, 2015
|
|
* Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of version 2 of the GNU Lesser General Public License
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it would be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
|
|
*
|
|
*/
|
|
|
|
#include <linux/mm.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/mmu.h>
|
|
/*
|
|
* index from 0 - 15
|
|
*/
|
|
bool __rpte_sub_valid(real_pte_t rpte, unsigned long index)
|
|
{
|
|
unsigned long g_idx;
|
|
unsigned long ptev = pte_val(rpte.pte);
|
|
|
|
g_idx = (ptev & H_PAGE_COMBO_VALID) >> H_PAGE_F_GIX_SHIFT;
|
|
index = index >> 2;
|
|
if (g_idx & (0x1 << index))
|
|
return true;
|
|
else
|
|
return false;
|
|
}
|
|
/*
|
|
* index from 0 - 15
|
|
*/
|
|
static unsigned long mark_subptegroup_valid(unsigned long ptev, unsigned long index)
|
|
{
|
|
unsigned long g_idx;
|
|
|
|
if (!(ptev & H_PAGE_COMBO))
|
|
return ptev;
|
|
index = index >> 2;
|
|
g_idx = 0x1 << index;
|
|
|
|
return ptev | (g_idx << H_PAGE_F_GIX_SHIFT);
|
|
}
|
|
|
|
int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
|
|
pte_t *ptep, unsigned long trap, unsigned long flags,
|
|
int ssize, int subpg_prot)
|
|
{
|
|
real_pte_t rpte;
|
|
unsigned long *hidxp;
|
|
unsigned long hpte_group;
|
|
unsigned int subpg_index;
|
|
unsigned long rflags, pa, hidx;
|
|
unsigned long old_pte, new_pte, subpg_pte;
|
|
unsigned long vpn, hash, slot;
|
|
unsigned long shift = mmu_psize_defs[MMU_PAGE_4K].shift;
|
|
|
|
/*
|
|
* atomically mark the linux large page PTE busy and dirty
|
|
*/
|
|
do {
|
|
pte_t pte = READ_ONCE(*ptep);
|
|
|
|
old_pte = pte_val(pte);
|
|
/* 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. Since this is 4K insert of 64K page size
|
|
* also add H_PAGE_COMBO
|
|
*/
|
|
new_pte = old_pte | H_PAGE_BUSY | _PAGE_ACCESSED | H_PAGE_COMBO;
|
|
if (access & _PAGE_WRITE)
|
|
new_pte |= _PAGE_DIRTY;
|
|
} while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));
|
|
|
|
/*
|
|
* Handle the subpage protection bits
|
|
*/
|
|
subpg_pte = new_pte & ~subpg_prot;
|
|
rflags = htab_convert_pte_flags(subpg_pte);
|
|
|
|
if (!cpu_has_feature(CPU_FTR_NOEXECUTE) &&
|
|
!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);
|
|
}
|
|
|
|
subpg_index = (ea & (PAGE_SIZE - 1)) >> shift;
|
|
vpn = hpt_vpn(ea, vsid, ssize);
|
|
rpte = __real_pte(__pte(old_pte), ptep);
|
|
/*
|
|
*None of the sub 4k page is hashed
|
|
*/
|
|
if (!(old_pte & H_PAGE_HASHPTE))
|
|
goto htab_insert_hpte;
|
|
/*
|
|
* Check if the pte was already inserted into the hash table
|
|
* as a 64k HW page, and invalidate the 64k HPTE if so.
|
|
*/
|
|
if (!(old_pte & H_PAGE_COMBO)) {
|
|
flush_hash_page(vpn, rpte, MMU_PAGE_64K, ssize, flags);
|
|
/*
|
|
* clear the old slot details from the old and new pte.
|
|
* On hash insert failure we use old pte value and we don't
|
|
* want slot information there if we have a insert failure.
|
|
*/
|
|
old_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
|
|
new_pte &= ~(H_PAGE_HASHPTE | H_PAGE_F_GIX | H_PAGE_F_SECOND);
|
|
goto htab_insert_hpte;
|
|
}
|
|
/*
|
|
* Check for sub page valid and update
|
|
*/
|
|
if (__rpte_sub_valid(rpte, subpg_index)) {
|
|
int ret;
|
|
|
|
hash = hpt_hash(vpn, shift, ssize);
|
|
hidx = __rpte_to_hidx(rpte, subpg_index);
|
|
if (hidx & _PTEIDX_SECONDARY)
|
|
hash = ~hash;
|
|
slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
|
|
slot += hidx & _PTEIDX_GROUP_IX;
|
|
|
|
ret = ppc_md.hpte_updatepp(slot, rflags, vpn,
|
|
MMU_PAGE_4K, MMU_PAGE_4K,
|
|
ssize, flags);
|
|
/*
|
|
*if we failed because typically the HPTE wasn't really here
|
|
* we try an insertion.
|
|
*/
|
|
if (ret == -1)
|
|
goto htab_insert_hpte;
|
|
|
|
*ptep = __pte(new_pte & ~H_PAGE_BUSY);
|
|
return 0;
|
|
}
|
|
|
|
htab_insert_hpte:
|
|
/*
|
|
* handle H_PAGE_4K_PFN case
|
|
*/
|
|
if (old_pte & H_PAGE_4K_PFN) {
|
|
/*
|
|
* All the sub 4k page have the same
|
|
* physical address.
|
|
*/
|
|
pa = pte_pfn(__pte(old_pte)) << HW_PAGE_SHIFT;
|
|
} else {
|
|
pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
|
|
pa += (subpg_index << shift);
|
|
}
|
|
hash = hpt_hash(vpn, shift, ssize);
|
|
repeat:
|
|
hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
|
|
|
|
/* Insert into the hash table, primary slot */
|
|
slot = ppc_md.hpte_insert(hpte_group, vpn, pa, rflags, 0,
|
|
MMU_PAGE_4K, MMU_PAGE_4K, ssize);
|
|
/*
|
|
* Primary is full, try the secondary
|
|
*/
|
|
if (unlikely(slot == -1)) {
|
|
hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
|
|
slot = ppc_md.hpte_insert(hpte_group, vpn, pa,
|
|
rflags, HPTE_V_SECONDARY,
|
|
MMU_PAGE_4K, MMU_PAGE_4K, ssize);
|
|
if (slot == -1) {
|
|
if (mftb() & 0x1)
|
|
hpte_group = ((hash & htab_hash_mask) *
|
|
HPTES_PER_GROUP) & ~0x7UL;
|
|
ppc_md.hpte_remove(hpte_group);
|
|
/*
|
|
* FIXME!! Should be try the group from which we removed ?
|
|
*/
|
|
goto repeat;
|
|
}
|
|
}
|
|
/*
|
|
* 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_PAGE_4K, MMU_PAGE_4K, old_pte);
|
|
return -1;
|
|
}
|
|
/*
|
|
* Insert slot number & secondary bit in PTE second half,
|
|
* clear H_PAGE_BUSY and set appropriate HPTE slot bit
|
|
* Since we have H_PAGE_BUSY set on ptep, we can be sure
|
|
* nobody is undating hidx.
|
|
*/
|
|
hidxp = (unsigned long *)(ptep + PTRS_PER_PTE);
|
|
rpte.hidx &= ~(0xfUL << (subpg_index << 2));
|
|
*hidxp = rpte.hidx | (slot << (subpg_index << 2));
|
|
new_pte = mark_subptegroup_valid(new_pte, subpg_index);
|
|
new_pte |= H_PAGE_HASHPTE;
|
|
/*
|
|
* check __real_pte for details on matching smp_rmb()
|
|
*/
|
|
smp_wmb();
|
|
*ptep = __pte(new_pte & ~H_PAGE_BUSY);
|
|
return 0;
|
|
}
|
|
|
|
int __hash_page_64K(unsigned long ea, unsigned long access,
|
|
unsigned long vsid, pte_t *ptep, unsigned long trap,
|
|
unsigned long flags, int ssize)
|
|
{
|
|
unsigned long hpte_group;
|
|
unsigned long rflags, pa;
|
|
unsigned long old_pte, new_pte;
|
|
unsigned long vpn, hash, slot;
|
|
unsigned long shift = mmu_psize_defs[MMU_PAGE_64K].shift;
|
|
|
|
/*
|
|
* atomically mark the linux large page PTE busy and dirty
|
|
*/
|
|
do {
|
|
pte_t pte = READ_ONCE(*ptep);
|
|
|
|
old_pte = pte_val(pte);
|
|
/* 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;
|
|
/*
|
|
* Check if PTE has the cache-inhibit bit set
|
|
* If so, bail out and refault as a 4k page
|
|
*/
|
|
if (!mmu_has_feature(MMU_FTR_CI_LARGE_PAGE) &&
|
|
unlikely(pte_ci(pte)))
|
|
return 0;
|
|
/*
|
|
* 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);
|
|
|
|
if (!cpu_has_feature(CPU_FTR_NOEXECUTE) &&
|
|
!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
|
|
rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap);
|
|
|
|
vpn = hpt_vpn(ea, vsid, ssize);
|
|
if (unlikely(old_pte & H_PAGE_HASHPTE)) {
|
|
/*
|
|
* There MIGHT be an HPTE for this pte
|
|
*/
|
|
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 (ppc_md.hpte_updatepp(slot, rflags, vpn, MMU_PAGE_64K,
|
|
MMU_PAGE_64K, ssize, flags) == -1)
|
|
old_pte &= ~_PAGE_HPTEFLAGS;
|
|
}
|
|
|
|
if (likely(!(old_pte & H_PAGE_HASHPTE))) {
|
|
|
|
pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
|
|
hash = hpt_hash(vpn, shift, ssize);
|
|
|
|
repeat:
|
|
hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
|
|
|
|
/* Insert into the hash table, primary slot */
|
|
slot = ppc_md.hpte_insert(hpte_group, vpn, pa, rflags, 0,
|
|
MMU_PAGE_64K, MMU_PAGE_64K, ssize);
|
|
/*
|
|
* Primary is full, try the secondary
|
|
*/
|
|
if (unlikely(slot == -1)) {
|
|
hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
|
|
slot = ppc_md.hpte_insert(hpte_group, vpn, pa,
|
|
rflags, HPTE_V_SECONDARY,
|
|
MMU_PAGE_64K, MMU_PAGE_64K, ssize);
|
|
if (slot == -1) {
|
|
if (mftb() & 0x1)
|
|
hpte_group = ((hash & htab_hash_mask) *
|
|
HPTES_PER_GROUP) & ~0x7UL;
|
|
ppc_md.hpte_remove(hpte_group);
|
|
/*
|
|
* FIXME!! Should be try the group from which we removed ?
|
|
*/
|
|
goto repeat;
|
|
}
|
|
}
|
|
/*
|
|
* 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_PAGE_64K, MMU_PAGE_64K, old_pte);
|
|
return -1;
|
|
}
|
|
new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | H_PAGE_HASHPTE;
|
|
new_pte |= (slot << H_PAGE_F_GIX_SHIFT) &
|
|
(H_PAGE_F_SECOND | H_PAGE_F_GIX);
|
|
}
|
|
*ptep = __pte(new_pte & ~H_PAGE_BUSY);
|
|
return 0;
|
|
}
|