diff options
Diffstat (limited to 'arch/sh/mm/tlbex_64.c')
| -rw-r--r-- | arch/sh/mm/tlbex_64.c | 166 |
1 files changed, 0 insertions, 166 deletions
diff --git a/arch/sh/mm/tlbex_64.c b/arch/sh/mm/tlbex_64.c deleted file mode 100644 index 8ff966dd0c74..000000000000 --- a/arch/sh/mm/tlbex_64.c +++ /dev/null @@ -1,166 +0,0 @@ -/* - * The SH64 TLB miss. - * - * Original code from fault.c - * Copyright (C) 2000, 2001 Paolo Alberelli - * - * Fast PTE->TLB refill path - * 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. - * - * 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> -#include <linux/errno.h> -#include <linux/string.h> -#include <linux/types.h> -#include <linux/ptrace.h> -#include <linux/mman.h> -#include <linux/mm.h> -#include <linux/smp.h> -#include <linux/interrupt.h> -#include <linux/kprobes.h> -#include <asm/tlb.h> -#include <asm/io.h> -#include <linux/uaccess.h> -#include <asm/pgalloc.h> -#include <asm/mmu_context.h> - -static int handle_tlbmiss(unsigned long long protection_flags, - unsigned long address) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - pte_t entry; - - if (is_vmalloc_addr((void *)address)) { - pgd = pgd_offset_k(address); - } else { - if (unlikely(address >= TASK_SIZE || !current->mm)) - return 1; - - pgd = pgd_offset(current->mm, address); - } - - pud = pud_offset(pgd, address); - if (pud_none(*pud) || !pud_present(*pud)) - return 1; - - pmd = pmd_offset(pud, address); - if (pmd_none(*pmd) || !pmd_present(*pmd)) - return 1; - - pte = pte_offset_kernel(pmd, address); - entry = *pte; - if (pte_none(entry) || !pte_present(entry)) - return 1; - - /* - * 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 1; - - update_mmu_cache(NULL, address, pte); - - return 0; -} - -/* - * 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]; - unsigned char is_write_access[8]; -}; - -#define PRU (1<<9) -#define PRW (1<<8) -#define PRX (1<<7) -#define PRR (1<<6) - -/* Sized as 8 rather than 4 to allow checking the PTE's PRU bit against whether - the fault happened in user mode or privileged mode. */ -static struct expevt_lookup expevt_lookup_table = { - .protection_flags = {PRX, PRX, 0, 0, PRR, PRR, PRW, PRW}, - .is_text_access = {1, 1, 0, 0, 0, 0, 0, 0} -}; - -static inline unsigned int -expevt_to_fault_code(unsigned long expevt) -{ - if (expevt == 0xa40) - return FAULT_CODE_ITLB; - else if (expevt == 0x060) - return FAULT_CODE_WRITE; - - return 0; -} - -/* - This routine handles page faults that can be serviced just by refilling a - TLB entry from an existing page table entry. (This case represents a very - large majority of page faults.) Return 1 if the fault was successfully - handled. Return 0 if the fault could not be handled. (This leads into the - general fault handling in fault.c which deals with mapping file-backed - pages, stack growth, segmentation faults, swapping etc etc) - */ -asmlinkage int __kprobes -do_fast_page_fault(unsigned long long ssr_md, unsigned long long expevt, - unsigned long address) -{ - unsigned long long protection_flags; - unsigned long long index; - unsigned long long expevt4; - unsigned int fault_code; - - /* 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. */ - index = expevt4 ^ (expevt4 >> 5); - index &= 7; - - fault_code = expevt_to_fault_code(expevt); - - protection_flags = expevt_lookup_table.protection_flags[index]; - - if (expevt_lookup_table.is_text_access[index]) - fault_code |= FAULT_CODE_ITLB; - if (!ssr_md) - fault_code |= FAULT_CODE_USER; - - set_thread_fault_code(fault_code); - - return handle_tlbmiss(protection_flags, address); -} |