Commit 811d50cb authored by Paul Mundt's avatar Paul Mundt

sh: Move in the SH-5 TLB miss.

Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 379a95d1
......@@ -12,7 +12,7 @@ obj-$(CONFIG_SH7705_CACHE_32KB) += cache-sh7705.o
endif
mmu-y := tlb-nommu.o pg-nommu.o
mmu-$(CONFIG_MMU) := fault.o clear_page.o copy_page.o tlb-flush_32.o \
mmu-$(CONFIG_MMU) := fault_32.o clear_page.o copy_page.o tlb-flush_32.o \
ioremap_32.o
obj-y += $(mmu-y)
......
......@@ -5,7 +5,7 @@
obj-y := init.o extable_64.o consistent.o
mmu-y := tlb-nommu.o pg-nommu.o
mmu-$(CONFIG_MMU) := ioremap_64.o tlb-flush_64.o
mmu-$(CONFIG_MMU) := fault_64.o ioremap_64.o tlb-flush_64.o
obj-y += $(mmu-y)
......
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* arch/sh64/mm/tlbmiss.c
* The SH64 TLB miss.
*
* Original code from fault.c
* Copyright (C) 2000, 2001 Paolo Alberelli
......@@ -12,16 +8,20 @@
* Copyright (C) 2003 Richard.Curnow@superh.com
*
* IMPORTANT NOTES :
* The do_fast_page_fault function is called from a context in entry.S where very few registers
* have been saved. In particular, the code in this file must be compiled not to use ANY
* caller-save registers that are not part of the restricted save set. Also, it means that
* code in this file must not make calls to functions elsewhere in the kernel, or else the
* excepting context will see corruption in its caller-save registers. Plus, the entry.S save
* area is non-reentrant, so this code has to run with SR.BL==1, i.e. no interrupts taken inside
* it and panic on any exception.
* The do_fast_page_fault function is called from a context in entry.S
* where very few registers have been saved. In particular, the code in
* this file must be compiled not to use ANY caller-save registers that
* are not part of the restricted save set. Also, it means that code in
* this file must not make calls to functions elsewhere in the kernel, or
* else the excepting context will see corruption in its caller-save
* registers. Plus, the entry.S save area is non-reentrant, so this code
* has to run with SR.BL==1, i.e. no interrupts taken inside it and panic
* on any exception.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
......@@ -33,14 +33,13 @@
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <asm/system.h>
#include <asm/tlb.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/pgalloc.h>
#include <asm/mmu_context.h>
#include <asm/registers.h> /* required by inline asm statements */
#include <asm/cpu/registers.h>
/* Callable from fault.c, so not static */
inline void __do_tlb_refill(unsigned long address,
......@@ -88,48 +87,47 @@ inline void __do_tlb_refill(unsigned long address,
}
static int handle_vmalloc_fault(struct mm_struct *mm, unsigned long protection_flags,
static int handle_vmalloc_fault(struct mm_struct *mm,
unsigned long protection_flags,
unsigned long long textaccess,
unsigned long address)
{
pgd_t *dir;
pud_t *pud;
pmd_t *pmd;
static pte_t *pte;
pte_t entry;
dir = pgd_offset_k(address);
pmd = pmd_offset(dir, address);
if (pmd_none(*pmd)) {
pud = pud_offset(dir, address);
if (pud_none_or_clear_bad(pud))
return 0;
}
if (pmd_bad(*pmd)) {
pmd_clear(pmd);
pmd = pmd_offset(pud, address);
if (pmd_none_or_clear_bad(pmd))
return 0;
}
pte = pte_offset_kernel(pmd, address);
entry = *pte;
if (pte_none(entry) || !pte_present(entry)) {
if (pte_none(entry) || !pte_present(entry))
return 0;
}
if ((pte_val(entry) & protection_flags) != protection_flags) {
if ((pte_val(entry) & protection_flags) != protection_flags)
return 0;
}
__do_tlb_refill(address, textaccess, pte);
return 1;
}
static int handle_tlbmiss(struct mm_struct *mm, unsigned long long protection_flags,
unsigned long long textaccess,
unsigned long address)
static int handle_tlbmiss(struct mm_struct *mm,
unsigned long long protection_flags,
unsigned long long textaccess,
unsigned long address)
{
pgd_t *dir;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
pte_t entry;
......@@ -144,49 +142,49 @@ static int handle_tlbmiss(struct mm_struct *mm, unsigned long long protection_fl
See how mm->pgd is allocated and initialised in pgd_alloc to see why
the next test is necessary. - RPC */
if (address >= (unsigned long) TASK_SIZE) {
if (address >= (unsigned long) TASK_SIZE)
/* upper half - never has page table entries. */
return 0;
}
dir = pgd_offset(mm, address);
if (pgd_none(*dir)) {
if (pgd_none(*dir) || !pgd_present(*dir))
return 0;
}
if (!pgd_present(*dir)) {
if (!pgd_present(*dir))
return 0;
}
pmd = pmd_offset(dir, address);
if (pmd_none(*pmd)) {
pud = pud_offset(dir, address);
if (pud_none(*pud) || !pud_present(*pud))
return 0;
}
if (!pmd_present(*pmd)) {
pmd = pmd_offset(pud, address);
if (pmd_none(*pmd) || !pmd_present(*pmd))
return 0;
}
pte = pte_offset_kernel(pmd, address);
entry = *pte;
if (pte_none(entry)) {
return 0;
}
if (!pte_present(entry)) {
if (pte_none(entry) || !pte_present(entry))
return 0;
}
/* If the page doesn't have sufficient protection bits set to service the
kind of fault being handled, there's not much point doing the TLB refill.
Punt the fault to the general handler. */
if ((pte_val(entry) & protection_flags) != protection_flags) {
/*
* If the page doesn't have sufficient protection bits set to
* service the kind of fault being handled, there's not much
* point doing the TLB refill. Punt the fault to the general
* handler.
*/
if ((pte_val(entry) & protection_flags) != protection_flags)
return 0;
}
__do_tlb_refill(address, textaccess, pte);
return 1;
}
/* Put all this information into one structure so that everything is just arithmetic
relative to a single base address. This reduces the number of movi/shori pairs needed
just to load addresses of static data. */
/*
* Put all this information into one structure so that everything is just
* arithmetic relative to a single base address. This reduces the number
* of movi/shori pairs needed just to load addresses of static data.
*/
struct expevt_lookup {
unsigned short protection_flags[8];
unsigned char is_text_access[8];
......@@ -216,7 +214,8 @@ static struct expevt_lookup expevt_lookup_table = {
general fault handling in fault.c which deals with mapping file-backed
pages, stack growth, segmentation faults, swapping etc etc)
*/
asmlinkage int do_fast_page_fault(unsigned long long ssr_md, unsigned long long expevt,
asmlinkage int do_fast_page_fault(unsigned long long ssr_md,
unsigned long long expevt,
unsigned long address)
{
struct task_struct *tsk;
......@@ -226,17 +225,18 @@ asmlinkage int do_fast_page_fault(unsigned long long ssr_md, unsigned long long
unsigned long long index;
unsigned long long expevt4;
/* The next few lines implement a way of hashing EXPEVT into a small array index
which can be used to lookup parameters specific to the type of TLBMISS being
handled. Note:
ITLBMISS has EXPEVT==0xa40
RTLBMISS has EXPEVT==0x040
WTLBMISS has EXPEVT==0x060
*/
/* The next few lines implement a way of hashing EXPEVT into a
* small array index which can be used to lookup parameters
* specific to the type of TLBMISS being handled.
*
* Note:
* ITLBMISS has EXPEVT==0xa40
* RTLBMISS has EXPEVT==0x040
* WTLBMISS has EXPEVT==0x060
*/
expevt4 = (expevt >> 4);
/* TODO : xor ssr_md into this expression too. Then we can check that PRU is set
when it needs to be. */
/* TODO : xor ssr_md into this expression too. Then we can check
* that PRU is set when it needs to be. */
index = expevt4 ^ (expevt4 >> 5);
index &= 7;
protection_flags = expevt_lookup_table.protection_flags[index];
......@@ -262,18 +262,18 @@ asmlinkage int do_fast_page_fault(unsigned long long ssr_md, unsigned long long
if ((address >= VMALLOC_START && address < VMALLOC_END) ||
(address >= IOBASE_VADDR && address < IOBASE_END)) {
if (ssr_md) {
/* Process-contexts can never have this address range mapped */
if (handle_vmalloc_fault(mm, protection_flags, textaccess, address)) {
if (ssr_md)
/*
* Process-contexts can never have this address
* range mapped
*/
if (handle_vmalloc_fault(mm, protection_flags,
textaccess, address))
return 1;
}
}
} else if (!in_interrupt() && mm) {
if (handle_tlbmiss(mm, protection_flags, textaccess, address)) {
if (handle_tlbmiss(mm, protection_flags, textaccess, address))
return 1;
}
}
return 0;
}
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