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-rw-r--r--arch/ppc/mm/fault.c436
1 files changed, 0 insertions, 436 deletions
diff --git a/arch/ppc/mm/fault.c b/arch/ppc/mm/fault.c
deleted file mode 100644
index 36c0e75..0000000
--- a/arch/ppc/mm/fault.c
+++ /dev/null
@@ -1,436 +0,0 @@
-/*
- * PowerPC version
- * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
- *
- * Derived from "arch/i386/mm/fault.c"
- * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
- *
- * Modified by Cort Dougan and Paul Mackerras.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#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/interrupt.h>
-#include <linux/highmem.h>
-#include <linux/module.h>
-
-#include <asm/page.h>
-#include <asm/pgtable.h>
-#include <asm/mmu.h>
-#include <asm/mmu_context.h>
-#include <asm/system.h>
-#include <asm/uaccess.h>
-#include <asm/tlbflush.h>
-
-#if defined(CONFIG_XMON) || defined(CONFIG_KGDB)
-extern void (*debugger)(struct pt_regs *);
-extern void (*debugger_fault_handler)(struct pt_regs *);
-extern int (*debugger_dabr_match)(struct pt_regs *);
-int debugger_kernel_faults = 1;
-#endif
-
-unsigned long htab_reloads; /* updated by hashtable.S:hash_page() */
-unsigned long htab_evicts; /* updated by hashtable.S:hash_page() */
-unsigned long htab_preloads; /* updated by hashtable.S:add_hash_page() */
-unsigned long pte_misses; /* updated by do_page_fault() */
-unsigned long pte_errors; /* updated by do_page_fault() */
-unsigned int probingmem;
-
-/*
- * Check whether the instruction at regs->nip is a store using
- * an update addressing form which will update r1.
- */
-static int store_updates_sp(struct pt_regs *regs)
-{
- unsigned int inst;
-
- if (get_user(inst, (unsigned int __user *)regs->nip))
- return 0;
- /* check for 1 in the rA field */
- if (((inst >> 16) & 0x1f) != 1)
- return 0;
- /* check major opcode */
- switch (inst >> 26) {
- case 37: /* stwu */
- case 39: /* stbu */
- case 45: /* sthu */
- case 53: /* stfsu */
- case 55: /* stfdu */
- return 1;
- case 31:
- /* check minor opcode */
- switch ((inst >> 1) & 0x3ff) {
- case 183: /* stwux */
- case 247: /* stbux */
- case 439: /* sthux */
- case 695: /* stfsux */
- case 759: /* stfdux */
- return 1;
- }
- }
- return 0;
-}
-
-/*
- * For 600- and 800-family processors, the error_code parameter is DSISR
- * for a data fault, SRR1 for an instruction fault. For 400-family processors
- * the error_code parameter is ESR for a data fault, 0 for an instruction
- * fault.
- */
-int do_page_fault(struct pt_regs *regs, unsigned long address,
- unsigned long error_code)
-{
- struct vm_area_struct * vma;
- struct mm_struct *mm = current->mm;
- siginfo_t info;
- int code = SEGV_MAPERR;
- int fault;
-#if defined(CONFIG_4xx) || defined (CONFIG_BOOKE)
- int is_write = error_code & ESR_DST;
-#else
- int is_write = 0;
-
- /*
- * Fortunately the bit assignments in SRR1 for an instruction
- * fault and DSISR for a data fault are mostly the same for the
- * bits we are interested in. But there are some bits which
- * indicate errors in DSISR but can validly be set in SRR1.
- */
- if (TRAP(regs) == 0x400)
- error_code &= 0x48200000;
- else
- is_write = error_code & 0x02000000;
-#endif /* CONFIG_4xx || CONFIG_BOOKE */
-
-#if defined(CONFIG_XMON) || defined(CONFIG_KGDB)
- if (debugger_fault_handler && TRAP(regs) == 0x300) {
- debugger_fault_handler(regs);
- return 0;
- }
-#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))
- if (error_code & 0x00400000) {
- /* DABR match */
- if (debugger_dabr_match(regs))
- return 0;
- }
-#endif /* !(CONFIG_4xx || CONFIG_BOOKE)*/
-#endif /* CONFIG_XMON || CONFIG_KGDB */
-
- if (in_atomic() || mm == NULL)
- return SIGSEGV;
-
- down_read(&mm->mmap_sem);
- vma = find_vma(mm, address);
- if (!vma)
- goto bad_area;
- if (vma->vm_start <= address)
- goto good_area;
- if (!(vma->vm_flags & VM_GROWSDOWN))
- goto bad_area;
- if (!is_write)
- goto bad_area;
-
- /*
- * N.B. The rs6000/xcoff ABI allows programs to access up to
- * a few hundred bytes below the stack pointer.
- * The kernel signal delivery code writes up to about 1.5kB
- * below the stack pointer (r1) before decrementing it.
- * The exec code can write slightly over 640kB to the stack
- * before setting the user r1. Thus we allow the stack to
- * expand to 1MB without further checks.
- */
- if (address + 0x100000 < vma->vm_end) {
- /* get user regs even if this fault is in kernel mode */
- struct pt_regs *uregs = current->thread.regs;
- if (uregs == NULL)
- goto bad_area;
-
- /*
- * A user-mode access to an address a long way below
- * the stack pointer is only valid if the instruction
- * is one which would update the stack pointer to the
- * address accessed if the instruction completed,
- * i.e. either stwu rs,n(r1) or stwux rs,r1,rb
- * (or the byte, halfword, float or double forms).
- *
- * If we don't check this then any write to the area
- * between the last mapped region and the stack will
- * expand the stack rather than segfaulting.
- */
- if (address + 2048 < uregs->gpr[1]
- && (!user_mode(regs) || !store_updates_sp(regs)))
- goto bad_area;
- }
- if (expand_stack(vma, address))
- goto bad_area;
-
-good_area:
- code = SEGV_ACCERR;
-#if defined(CONFIG_6xx)
- if (error_code & 0x95700000)
- /* an error such as lwarx to I/O controller space,
- address matching DABR, eciwx, etc. */
- goto bad_area;
-#endif /* CONFIG_6xx */
-#if defined(CONFIG_8xx)
- /* The MPC8xx seems to always set 0x80000000, which is
- * "undefined". Of those that can be set, this is the only
- * one which seems bad.
- */
- if (error_code & 0x10000000)
- /* Guarded storage error. */
- goto bad_area;
-#endif /* CONFIG_8xx */
-
- /* a write */
- if (is_write) {
- if (!(vma->vm_flags & VM_WRITE))
- goto bad_area;
-#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
- /* an exec - 4xx/Book-E allows for per-page execute permission */
- } else if (TRAP(regs) == 0x400) {
- pte_t *ptep;
- pmd_t *pmdp;
-
-#if 0
- /* It would be nice to actually enforce the VM execute
- permission on CPUs which can do so, but far too
- much stuff in userspace doesn't get the permissions
- right, so we let any page be executed for now. */
- if (! (vma->vm_flags & VM_EXEC))
- goto bad_area;
-#endif
-
- /* Since 4xx/Book-E supports per-page execute permission,
- * we lazily flush dcache to icache. */
- ptep = NULL;
- if (get_pteptr(mm, address, &ptep, &pmdp)) {
- spinlock_t *ptl = pte_lockptr(mm, pmdp);
- spin_lock(ptl);
- if (pte_present(*ptep)) {
- struct page *page = pte_page(*ptep);
-
- if (!test_bit(PG_arch_1, &page->flags)) {
- flush_dcache_icache_page(page);
- set_bit(PG_arch_1, &page->flags);
- }
- pte_update(ptep, 0, _PAGE_HWEXEC);
- _tlbie(address, mm->context.id);
- pte_unmap_unlock(ptep, ptl);
- up_read(&mm->mmap_sem);
- return 0;
- }
- pte_unmap_unlock(ptep, ptl);
- }
-#endif
- /* a read */
- } else {
- /* protection fault */
- if (error_code & 0x08000000)
- goto bad_area;
- if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
- goto bad_area;
- }
-
- /*
- * If for any reason at all we couldn't handle the fault,
- * make sure we exit gracefully rather than endlessly redo
- * the fault.
- */
- survive:
- fault = handle_mm_fault(mm, vma, address, is_write);
- if (unlikely(fault & VM_FAULT_ERROR)) {
- if (fault & VM_FAULT_OOM)
- goto out_of_memory;
- else if (fault & VM_FAULT_SIGBUS)
- goto do_sigbus;
- BUG();
- }
- if (fault & VM_FAULT_MAJOR)
- current->maj_flt++;
- else
- current->min_flt++;
-
- up_read(&mm->mmap_sem);
- /*
- * keep track of tlb+htab misses that are good addrs but
- * just need pte's created via handle_mm_fault()
- * -- Cort
- */
- pte_misses++;
- return 0;
-
-bad_area:
- up_read(&mm->mmap_sem);
- pte_errors++;
-
- /* User mode accesses cause a SIGSEGV */
- if (user_mode(regs)) {
- _exception(SIGSEGV, regs, code, address);
- return 0;
- }
-
- return SIGSEGV;
-
-/*
- * We ran out of memory, or some other thing happened to us that made
- * us unable to handle the page fault gracefully.
- */
-out_of_memory:
- up_read(&mm->mmap_sem);
- if (is_global_init(current)) {
- yield();
- down_read(&mm->mmap_sem);
- goto survive;
- }
- printk("VM: killing process %s\n", current->comm);
- if (user_mode(regs))
- do_group_exit(SIGKILL);
- return SIGKILL;
-
-do_sigbus:
- up_read(&mm->mmap_sem);
- info.si_signo = SIGBUS;
- info.si_errno = 0;
- info.si_code = BUS_ADRERR;
- info.si_addr = (void __user *)address;
- force_sig_info (SIGBUS, &info, current);
- if (!user_mode(regs))
- return SIGBUS;
- return 0;
-}
-
-/*
- * bad_page_fault is called when we have a bad access from the kernel.
- * It is called from the DSI and ISI handlers in head.S and from some
- * of the procedures in traps.c.
- */
-void
-bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
-{
- const struct exception_table_entry *entry;
-
- /* Are we prepared to handle this fault? */
- if ((entry = search_exception_tables(regs->nip)) != NULL) {
- regs->nip = entry->fixup;
- return;
- }
-
- /* kernel has accessed a bad area */
-#if defined(CONFIG_XMON) || defined(CONFIG_KGDB)
- if (debugger_kernel_faults)
- debugger(regs);
-#endif
- die("kernel access of bad area", regs, sig);
-}
-
-#ifdef CONFIG_8xx
-
-/* The pgtable.h claims some functions generically exist, but I
- * can't find them......
- */
-pte_t *va_to_pte(unsigned long address)
-{
- pgd_t *dir;
- pmd_t *pmd;
- pte_t *pte;
-
- if (address < TASK_SIZE)
- return NULL;
-
- dir = pgd_offset(&init_mm, address);
- if (dir) {
- pmd = pmd_offset(dir, address & PAGE_MASK);
- if (pmd && pmd_present(*pmd)) {
- pte = pte_offset_kernel(pmd, address & PAGE_MASK);
- if (pte && pte_present(*pte))
- return(pte);
- }
- }
- return NULL;
-}
-
-unsigned long va_to_phys(unsigned long address)
-{
- pte_t *pte;
-
- pte = va_to_pte(address);
- if (pte)
- return(((unsigned long)(pte_val(*pte)) & PAGE_MASK) | (address & ~(PAGE_MASK)));
- return (0);
-}
-
-void
-print_8xx_pte(struct mm_struct *mm, unsigned long addr)
-{
- pgd_t * pgd;
- pmd_t * pmd;
- pte_t * pte;
-
- printk(" pte @ 0x%8lx: ", addr);
- pgd = pgd_offset(mm, addr & PAGE_MASK);
- if (pgd) {
- pmd = pmd_offset(pgd, addr & PAGE_MASK);
- if (pmd && pmd_present(*pmd)) {
- pte = pte_offset_kernel(pmd, addr & PAGE_MASK);
- if (pte) {
- printk(" (0x%08lx)->(0x%08lx)->0x%08lx\n",
- (long)pgd, (long)pte, (long)pte_val(*pte));
-#define pp ((long)pte_val(*pte))
- printk(" RPN: %05lx PP: %lx SPS: %lx SH: %lx "
- "CI: %lx v: %lx\n",
- pp>>12, /* rpn */
- (pp>>10)&3, /* pp */
- (pp>>3)&1, /* small */
- (pp>>2)&1, /* shared */
- (pp>>1)&1, /* cache inhibit */
- pp&1 /* valid */
- );
-#undef pp
- }
- else {
- printk("no pte\n");
- }
- }
- else {
- printk("no pmd\n");
- }
- }
- else {
- printk("no pgd\n");
- }
-}
-
-int
-get_8xx_pte(struct mm_struct *mm, unsigned long addr)
-{
- pgd_t * pgd;
- pmd_t * pmd;
- pte_t * pte;
- int retval = 0;
-
- pgd = pgd_offset(mm, addr & PAGE_MASK);
- if (pgd) {
- pmd = pmd_offset(pgd, addr & PAGE_MASK);
- if (pmd && pmd_present(*pmd)) {
- pte = pte_offset_kernel(pmd, addr & PAGE_MASK);
- if (pte) {
- retval = (int)pte_val(*pte);
- }
- }
- }
- return(retval);
-}
-#endif /* CONFIG_8xx */
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