freebsd-dev/sys/powerpc/aim/moea64_native.c
Justin Hibbits 197a7e48c9 powerpc64/pmap: Simplify the code path for moea64_pte_replace_native()
Summary:
MOEA64_PTE_REPLACE() is called often with the pmap lock held, and
sometimes with the page pv lock held.  The less work done while holding
a lock, the better.  Since we are intending to replace the same PTE
(same hash index), we don't need to recalculate anything, just flat
replace the PTE.  This cuts more than 200 instructions off the
invalidating code path.  In addition, we don't need to replace a PTE
that's not occupied by this PVO.

Reviewed by:	luporl
Differential Revision:	https://reviews.freebsd.org/D21515
2019-09-06 02:45:46 +00:00

790 lines
22 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD AND 4-Clause-BSD
*
* Copyright (c) 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Matt Thomas <matt@3am-software.com> of Allegro Networks, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*-
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $NetBSD: pmap.c,v 1.28 2000/03/26 20:42:36 kleink Exp $
*/
/*-
* Copyright (C) 2001 Benno Rice.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Native 64-bit page table operations for running without a hypervisor.
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/sched.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/rwlock.h>
#include <sys/endian.h>
#include <sys/kdb.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <vm/vm_pageout.h>
#include <machine/cpu.h>
#include <machine/hid.h>
#include <machine/md_var.h>
#include <machine/mmuvar.h>
#include "mmu_oea64.h"
#include "mmu_if.h"
#include "moea64_if.h"
#define PTESYNC() __asm __volatile("ptesync");
#define TLBSYNC() __asm __volatile("tlbsync; ptesync");
#define SYNC() __asm __volatile("sync");
#define EIEIO() __asm __volatile("eieio");
#define VSID_HASH_MASK 0x0000007fffffffffULL
/* POWER9 only permits a 64k partition table size. */
#define PART_SIZE 0x10000
static bool moea64_crop_tlbie;
static bool moea64_need_lock;
static __inline void
TLBIE(uint64_t vpn) {
#ifndef __powerpc64__
register_t vpn_hi, vpn_lo;
register_t msr;
register_t scratch, intr;
#endif
static volatile u_int tlbie_lock = 0;
bool need_lock = moea64_need_lock;
vpn <<= ADDR_PIDX_SHFT;
/* Hobo spinlock: we need stronger guarantees than mutexes provide */
if (need_lock) {
while (!atomic_cmpset_int(&tlbie_lock, 0, 1));
isync(); /* Flush instruction queue once lock acquired */
if (moea64_crop_tlbie)
vpn &= ~(0xffffULL << 48);
}
#ifdef __powerpc64__
/*
* Explicitly clobber r0. The tlbie instruction has two forms: an old
* one used by PowerISA 2.03 and prior, and a newer one used by PowerISA
* 2.06 (maybe 2.05?) and later. We need to support both, and it just
* so happens that since we use 4k pages we can simply zero out r0, and
* clobber it, and the assembler will interpret the single-operand form
* of tlbie as having RB set, and everything else as 0. The RS operand
* in the newer form is in the same position as the L(page size) bit of
* the old form, so a slong as RS is 0, we're good on both sides.
*/
__asm __volatile("li 0, 0 \n tlbie %0" :: "r"(vpn) : "r0", "memory");
__asm __volatile("eieio; tlbsync; ptesync" ::: "memory");
#else
vpn_hi = (uint32_t)(vpn >> 32);
vpn_lo = (uint32_t)vpn;
intr = intr_disable();
__asm __volatile("\
mfmsr %0; \
mr %1, %0; \
insrdi %1,%5,1,0; \
mtmsrd %1; isync; \
\
sld %1,%2,%4; \
or %1,%1,%3; \
tlbie %1; \
\
mtmsrd %0; isync; \
eieio; \
tlbsync; \
ptesync;"
: "=r"(msr), "=r"(scratch) : "r"(vpn_hi), "r"(vpn_lo), "r"(32), "r"(1)
: "memory");
intr_restore(intr);
#endif
/* No barriers or special ops -- taken care of by ptesync above */
if (need_lock)
tlbie_lock = 0;
}
#define DISABLE_TRANS(msr) msr = mfmsr(); mtmsr(msr & ~PSL_DR)
#define ENABLE_TRANS(msr) mtmsr(msr)
/*
* PTEG data.
*/
static volatile struct lpte *moea64_pteg_table;
static struct rwlock moea64_eviction_lock;
static volatile struct pate *moea64_part_table;
/*
* PTE calls.
*/
static int moea64_pte_insert_native(mmu_t, struct pvo_entry *);
static int64_t moea64_pte_synch_native(mmu_t, struct pvo_entry *);
static int64_t moea64_pte_clear_native(mmu_t, struct pvo_entry *, uint64_t);
static int64_t moea64_pte_replace_native(mmu_t, struct pvo_entry *, int);
static int64_t moea64_pte_unset_native(mmu_t mmu, struct pvo_entry *);
/*
* Utility routines.
*/
static void moea64_bootstrap_native(mmu_t mmup,
vm_offset_t kernelstart, vm_offset_t kernelend);
static void moea64_cpu_bootstrap_native(mmu_t, int ap);
static void tlbia(void);
static mmu_method_t moea64_native_methods[] = {
/* Internal interfaces */
MMUMETHOD(mmu_bootstrap, moea64_bootstrap_native),
MMUMETHOD(mmu_cpu_bootstrap, moea64_cpu_bootstrap_native),
MMUMETHOD(moea64_pte_synch, moea64_pte_synch_native),
MMUMETHOD(moea64_pte_clear, moea64_pte_clear_native),
MMUMETHOD(moea64_pte_unset, moea64_pte_unset_native),
MMUMETHOD(moea64_pte_replace, moea64_pte_replace_native),
MMUMETHOD(moea64_pte_insert, moea64_pte_insert_native),
{ 0, 0 }
};
MMU_DEF_INHERIT(oea64_mmu_native, MMU_TYPE_G5, moea64_native_methods,
0, oea64_mmu);
static int64_t
moea64_pte_synch_native(mmu_t mmu, struct pvo_entry *pvo)
{
volatile struct lpte *pt = moea64_pteg_table + pvo->pvo_pte.slot;
struct lpte properpt;
uint64_t ptelo;
PMAP_LOCK_ASSERT(pvo->pvo_pmap, MA_OWNED);
moea64_pte_from_pvo(pvo, &properpt);
rw_rlock(&moea64_eviction_lock);
if ((be64toh(pt->pte_hi) & LPTE_AVPN_MASK) !=
(properpt.pte_hi & LPTE_AVPN_MASK)) {
/* Evicted */
rw_runlock(&moea64_eviction_lock);
return (-1);
}
PTESYNC();
ptelo = be64toh(pt->pte_lo);
rw_runlock(&moea64_eviction_lock);
return (ptelo & (LPTE_REF | LPTE_CHG));
}
static int64_t
moea64_pte_clear_native(mmu_t mmu, struct pvo_entry *pvo, uint64_t ptebit)
{
volatile struct lpte *pt = moea64_pteg_table + pvo->pvo_pte.slot;
struct lpte properpt;
uint64_t ptelo;
PMAP_LOCK_ASSERT(pvo->pvo_pmap, MA_OWNED);
moea64_pte_from_pvo(pvo, &properpt);
rw_rlock(&moea64_eviction_lock);
if ((be64toh(pt->pte_hi) & LPTE_AVPN_MASK) !=
(properpt.pte_hi & LPTE_AVPN_MASK)) {
/* Evicted */
rw_runlock(&moea64_eviction_lock);
return (-1);
}
if (ptebit == LPTE_REF) {
/* See "Resetting the Reference Bit" in arch manual */
PTESYNC();
/* 2-step here safe: precision is not guaranteed */
ptelo = be64toh(pt->pte_lo);
/* One-byte store to avoid touching the C bit */
((volatile uint8_t *)(&pt->pte_lo))[6] =
#if BYTE_ORDER == BIG_ENDIAN
((uint8_t *)(&properpt.pte_lo))[6];
#else
((uint8_t *)(&properpt.pte_lo))[1];
#endif
rw_runlock(&moea64_eviction_lock);
critical_enter();
TLBIE(pvo->pvo_vpn);
critical_exit();
} else {
rw_runlock(&moea64_eviction_lock);
ptelo = moea64_pte_unset_native(mmu, pvo);
moea64_pte_insert_native(mmu, pvo);
}
return (ptelo & (LPTE_REF | LPTE_CHG));
}
static int64_t
moea64_pte_unset_native(mmu_t mmu, struct pvo_entry *pvo)
{
volatile struct lpte *pt = moea64_pteg_table + pvo->pvo_pte.slot;
struct lpte properpt;
uint64_t ptelo;
moea64_pte_from_pvo(pvo, &properpt);
rw_rlock(&moea64_eviction_lock);
if ((be64toh(pt->pte_hi & LPTE_AVPN_MASK)) !=
(properpt.pte_hi & LPTE_AVPN_MASK)) {
/* Evicted */
STAT_MOEA64(moea64_pte_overflow--);
rw_runlock(&moea64_eviction_lock);
return (-1);
}
/*
* Invalidate the pte, briefly locking it to collect RC bits. No
* atomics needed since this is protected against eviction by the lock.
*/
isync();
critical_enter();
pt->pte_hi = be64toh((pt->pte_hi & ~LPTE_VALID) | LPTE_LOCKED);
PTESYNC();
TLBIE(pvo->pvo_vpn);
ptelo = be64toh(pt->pte_lo);
*((volatile int32_t *)(&pt->pte_hi) + 1) = 0; /* Release lock */
critical_exit();
rw_runlock(&moea64_eviction_lock);
/* Keep statistics */
STAT_MOEA64(moea64_pte_valid--);
return (ptelo & (LPTE_CHG | LPTE_REF));
}
static int64_t
moea64_pte_replace_inval_native(mmu_t mmu, struct pvo_entry *pvo,
volatile struct lpte *pt)
{
struct lpte properpt;
uint64_t ptelo;
moea64_pte_from_pvo(pvo, &properpt);
rw_rlock(&moea64_eviction_lock);
if ((be64toh(pt->pte_hi & LPTE_AVPN_MASK)) !=
(properpt.pte_hi & LPTE_AVPN_MASK)) {
/* Evicted */
STAT_MOEA64(moea64_pte_overflow--);
rw_runlock(&moea64_eviction_lock);
return (-1);
}
/*
* Replace the pte, briefly locking it to collect RC bits. No
* atomics needed since this is protected against eviction by the lock.
*/
isync();
critical_enter();
pt->pte_hi = be64toh((pt->pte_hi & ~LPTE_VALID) | LPTE_LOCKED);
PTESYNC();
TLBIE(pvo->pvo_vpn);
ptelo = be64toh(pt->pte_lo);
EIEIO();
pt->pte_lo = htobe64(properpt.pte_lo);
EIEIO();
pt->pte_hi = htobe64(properpt.pte_hi); /* Release lock */
PTESYNC();
critical_exit();
rw_runlock(&moea64_eviction_lock);
return (ptelo & (LPTE_CHG | LPTE_REF));
}
static int64_t
moea64_pte_replace_native(mmu_t mmu, struct pvo_entry *pvo, int flags)
{
volatile struct lpte *pt = moea64_pteg_table + pvo->pvo_pte.slot;
struct lpte properpt;
int64_t ptelo;
if (flags == 0) {
/* Just some software bits changing. */
moea64_pte_from_pvo(pvo, &properpt);
rw_rlock(&moea64_eviction_lock);
if ((be64toh(pt->pte_hi) & LPTE_AVPN_MASK) !=
(properpt.pte_hi & LPTE_AVPN_MASK)) {
rw_runlock(&moea64_eviction_lock);
return (-1);
}
pt->pte_hi = htobe64(properpt.pte_hi);
ptelo = be64toh(pt->pte_lo);
rw_runlock(&moea64_eviction_lock);
} else {
/* Otherwise, need reinsertion and deletion */
ptelo = moea64_pte_replace_inval_native(mmu, pvo, pt);
}
return (ptelo);
}
static void
moea64_cpu_bootstrap_native(mmu_t mmup, int ap)
{
int i = 0;
#ifdef __powerpc64__
struct slb *slb = PCPU_GET(aim.slb);
register_t seg0;
#endif
/*
* Initialize segment registers and MMU
*/
mtmsr(mfmsr() & ~PSL_DR & ~PSL_IR);
switch(mfpvr() >> 16) {
case IBMPOWER9:
mtspr(SPR_HID0, mfspr(SPR_HID0) & ~HID0_RADIX);
break;
}
/*
* Install kernel SLB entries
*/
#ifdef __powerpc64__
__asm __volatile ("slbia");
__asm __volatile ("slbmfee %0,%1; slbie %0;" : "=r"(seg0) :
"r"(0));
for (i = 0; i < n_slbs; i++) {
if (!(slb[i].slbe & SLBE_VALID))
continue;
__asm __volatile ("slbmte %0, %1" ::
"r"(slb[i].slbv), "r"(slb[i].slbe));
}
#else
for (i = 0; i < 16; i++)
mtsrin(i << ADDR_SR_SHFT, kernel_pmap->pm_sr[i]);
#endif
/*
* Install page table
*/
if (cpu_features2 & PPC_FEATURE2_ARCH_3_00)
mtspr(SPR_PTCR,
((uintptr_t)moea64_part_table & ~DMAP_BASE_ADDRESS) |
flsl((PART_SIZE >> 12) - 1));
else
__asm __volatile ("ptesync; mtsdr1 %0; isync"
:: "r"(((uintptr_t)moea64_pteg_table & ~DMAP_BASE_ADDRESS)
| (uintptr_t)(flsl(moea64_pteg_mask >> 11))));
tlbia();
}
static void
moea64_bootstrap_native(mmu_t mmup, vm_offset_t kernelstart,
vm_offset_t kernelend)
{
vm_size_t size;
vm_offset_t off;
vm_paddr_t pa;
register_t msr;
moea64_early_bootstrap(mmup, kernelstart, kernelend);
switch (mfpvr() >> 16) {
case IBMPOWER9:
moea64_need_lock = false;
break;
case IBMPOWER4:
case IBMPOWER4PLUS:
case IBM970:
case IBM970FX:
case IBM970GX:
case IBM970MP:
moea64_crop_tlbie = true;
default:
moea64_need_lock = true;
}
/*
* Allocate PTEG table.
*/
size = moea64_pteg_count * sizeof(struct lpteg);
CTR2(KTR_PMAP, "moea64_bootstrap: %lu PTEGs, %lu bytes",
moea64_pteg_count, size);
rw_init(&moea64_eviction_lock, "pte eviction");
/*
* We now need to allocate memory. This memory, to be allocated,
* has to reside in a page table. The page table we are about to
* allocate. We don't have BAT. So drop to data real mode for a minute
* as a measure of last resort. We do this a couple times.
*/
/*
* PTEG table must be aligned on a 256k boundary, but can be placed
* anywhere with that alignment on POWER ISA 3+ systems. On earlier
* systems, offset addition is done by the CPU with bitwise OR rather
* than addition, so the table must also be aligned on a boundary of
* its own size. Pick the larger of the two, which works on all
* systems.
*/
moea64_pteg_table = (struct lpte *)moea64_bootstrap_alloc(size,
MAX(256*1024, size));
if (hw_direct_map)
moea64_pteg_table =
(struct lpte *)PHYS_TO_DMAP((vm_offset_t)moea64_pteg_table);
/* Allocate partition table (ISA 3.0). */
if (cpu_features2 & PPC_FEATURE2_ARCH_3_00) {
moea64_part_table =
(struct pate *)moea64_bootstrap_alloc(PART_SIZE, PART_SIZE);
if (hw_direct_map)
moea64_part_table =
(struct pate *)PHYS_TO_DMAP((vm_offset_t)moea64_part_table);
}
DISABLE_TRANS(msr);
bzero(__DEVOLATILE(void *, moea64_pteg_table), moea64_pteg_count *
sizeof(struct lpteg));
if (cpu_features2 & PPC_FEATURE2_ARCH_3_00) {
bzero(__DEVOLATILE(void *, moea64_part_table), PART_SIZE);
moea64_part_table[0].pagetab =
(DMAP_TO_PHYS((vm_offset_t)moea64_pteg_table)) |
(uintptr_t)(flsl((moea64_pteg_count - 1) >> 11));
}
ENABLE_TRANS(msr);
CTR1(KTR_PMAP, "moea64_bootstrap: PTEG table at %p", moea64_pteg_table);
moea64_mid_bootstrap(mmup, kernelstart, kernelend);
/*
* Add a mapping for the page table itself if there is no direct map.
*/
if (!hw_direct_map) {
size = moea64_pteg_count * sizeof(struct lpteg);
off = (vm_offset_t)(moea64_pteg_table);
DISABLE_TRANS(msr);
for (pa = off; pa < off + size; pa += PAGE_SIZE)
pmap_kenter(pa, pa);
ENABLE_TRANS(msr);
}
/* Bring up virtual memory */
moea64_late_bootstrap(mmup, kernelstart, kernelend);
}
static void
tlbia(void)
{
vm_offset_t i;
#ifndef __powerpc64__
register_t msr, scratch;
#endif
i = 0xc00; /* IS = 11 */
switch (mfpvr() >> 16) {
case IBM970:
case IBM970FX:
case IBM970MP:
case IBM970GX:
case IBMPOWER4:
case IBMPOWER4PLUS:
case IBMPOWER5:
case IBMPOWER5PLUS:
i = 0; /* IS not supported */
break;
}
TLBSYNC();
for (; i < 0x400000; i += 0x00001000) {
#ifdef __powerpc64__
__asm __volatile("tlbiel %0" :: "r"(i));
#else
__asm __volatile("\
mfmsr %0; \
mr %1, %0; \
insrdi %1,%3,1,0; \
mtmsrd %1; \
isync; \
\
tlbiel %2; \
\
mtmsrd %0; \
isync;"
: "=r"(msr), "=r"(scratch) : "r"(i), "r"(1));
#endif
}
EIEIO();
TLBSYNC();
}
static int
atomic_pte_lock(volatile struct lpte *pte, uint64_t bitmask, uint64_t *oldhi)
{
int ret;
uint32_t oldhihalf;
/*
* Note: in principle, if just the locked bit were set here, we
* could avoid needing the eviction lock. However, eviction occurs
* so rarely that it isn't worth bothering about in practice.
*/
__asm __volatile (
"1:\tlwarx %1, 0, %3\n\t" /* load old value */
"and. %0,%1,%4\n\t" /* check if any bits set */
"bne 2f\n\t" /* exit if any set */
"stwcx. %5, 0, %3\n\t" /* attempt to store */
"bne- 1b\n\t" /* spin if failed */
"li %0, 1\n\t" /* success - retval = 1 */
"b 3f\n\t" /* we've succeeded */
"2:\n\t"
"stwcx. %1, 0, %3\n\t" /* clear reservation (74xx) */
"li %0, 0\n\t" /* failure - retval = 0 */
"3:\n\t"
: "=&r" (ret), "=&r"(oldhihalf), "=m" (pte->pte_hi)
: "r" ((volatile char *)&pte->pte_hi + 4),
"r" ((uint32_t)bitmask), "r" ((uint32_t)LPTE_LOCKED),
"m" (pte->pte_hi)
: "cr0", "cr1", "cr2", "memory");
*oldhi = (pte->pte_hi & 0xffffffff00000000ULL) | oldhihalf;
return (ret);
}
static uintptr_t
moea64_insert_to_pteg_native(struct lpte *pvo_pt, uintptr_t slotbase,
uint64_t mask)
{
volatile struct lpte *pt;
uint64_t oldptehi, va;
uintptr_t k;
int i, j;
/* Start at a random slot */
i = mftb() % 8;
for (j = 0; j < 8; j++) {
k = slotbase + (i + j) % 8;
pt = &moea64_pteg_table[k];
/* Invalidate and seize lock only if no bits in mask set */
if (atomic_pte_lock(pt, mask, &oldptehi)) /* Lock obtained */
break;
}
if (j == 8)
return (-1);
if (oldptehi & LPTE_VALID) {
KASSERT(!(oldptehi & LPTE_WIRED), ("Unmapped wired entry"));
/*
* Need to invalidate old entry completely: see
* "Modifying a Page Table Entry". Need to reconstruct
* the virtual address for the outgoing entry to do that.
*/
va = oldptehi >> (ADDR_SR_SHFT - ADDR_API_SHFT64);
if (oldptehi & LPTE_HID)
va = (((k >> 3) ^ moea64_pteg_mask) ^ va) &
(ADDR_PIDX >> ADDR_PIDX_SHFT);
else
va = ((k >> 3) ^ va) & (ADDR_PIDX >> ADDR_PIDX_SHFT);
va |= (oldptehi & LPTE_AVPN_MASK) <<
(ADDR_API_SHFT64 - ADDR_PIDX_SHFT);
PTESYNC();
TLBIE(va);
STAT_MOEA64(moea64_pte_valid--);
STAT_MOEA64(moea64_pte_overflow++);
}
/*
* Update the PTE as per "Adding a Page Table Entry". Lock is released
* by setting the high doubleworld.
*/
pt->pte_lo = htobe64(pvo_pt->pte_lo);
EIEIO();
pt->pte_hi = htobe64(pvo_pt->pte_hi);
PTESYNC();
/* Keep statistics */
STAT_MOEA64(moea64_pte_valid++);
return (k);
}
static int
moea64_pte_insert_native(mmu_t mmu, struct pvo_entry *pvo)
{
struct lpte insertpt;
uintptr_t slot;
/* Initialize PTE */
moea64_pte_from_pvo(pvo, &insertpt);
/* Make sure further insertion is locked out during evictions */
rw_rlock(&moea64_eviction_lock);
/*
* First try primary hash.
*/
pvo->pvo_pte.slot &= ~7ULL; /* Base slot address */
slot = moea64_insert_to_pteg_native(&insertpt, pvo->pvo_pte.slot,
LPTE_VALID | LPTE_WIRED | LPTE_LOCKED);
if (slot != -1) {
rw_runlock(&moea64_eviction_lock);
pvo->pvo_pte.slot = slot;
return (0);
}
/*
* Now try secondary hash.
*/
pvo->pvo_vaddr ^= PVO_HID;
insertpt.pte_hi ^= LPTE_HID;
pvo->pvo_pte.slot ^= (moea64_pteg_mask << 3);
slot = moea64_insert_to_pteg_native(&insertpt, pvo->pvo_pte.slot,
LPTE_VALID | LPTE_WIRED | LPTE_LOCKED);
if (slot != -1) {
rw_runlock(&moea64_eviction_lock);
pvo->pvo_pte.slot = slot;
return (0);
}
/*
* Out of luck. Find a PTE to sacrifice.
*/
/* Lock out all insertions for a bit */
if (!rw_try_upgrade(&moea64_eviction_lock)) {
rw_runlock(&moea64_eviction_lock);
rw_wlock(&moea64_eviction_lock);
}
slot = moea64_insert_to_pteg_native(&insertpt, pvo->pvo_pte.slot,
LPTE_WIRED | LPTE_LOCKED);
if (slot != -1) {
rw_wunlock(&moea64_eviction_lock);
pvo->pvo_pte.slot = slot;
return (0);
}
/* Try other hash table. Now we're getting desperate... */
pvo->pvo_vaddr ^= PVO_HID;
insertpt.pte_hi ^= LPTE_HID;
pvo->pvo_pte.slot ^= (moea64_pteg_mask << 3);
slot = moea64_insert_to_pteg_native(&insertpt, pvo->pvo_pte.slot,
LPTE_WIRED | LPTE_LOCKED);
if (slot != -1) {
rw_wunlock(&moea64_eviction_lock);
pvo->pvo_pte.slot = slot;
return (0);
}
/* No freeable slots in either PTEG? We're hosed. */
rw_wunlock(&moea64_eviction_lock);
panic("moea64_pte_insert: overflow");
return (-1);
}