diff options
author | David S. Miller <davem@davemloft.net> | 2008-07-18 02:39:39 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2008-07-18 02:39:39 -0700 |
commit | 49997d75152b3d23c53b0fa730599f2f74c92c65 (patch) | |
tree | 46e93126170d02cfec9505172e545732c1b69656 /arch/ppc/mm/fault.c | |
parent | a0c80b80e0fb48129e4e9d6a9ede914f9ff1850d (diff) | |
parent | 5b664cb235e97afbf34db9c4d77f08ebd725335e (diff) |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:
Documentation/powerpc/booting-without-of.txt
drivers/atm/Makefile
drivers/net/fs_enet/fs_enet-main.c
drivers/pci/pci-acpi.c
net/8021q/vlan.c
net/iucv/iucv.c
Diffstat (limited to 'arch/ppc/mm/fault.c')
-rw-r--r-- | arch/ppc/mm/fault.c | 436 |
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 36c0e7529ed..00000000000 --- 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 */ |