diff options
Diffstat (limited to 'arch/mips/mm/fault.c')
| -rw-r--r-- | arch/mips/mm/fault.c | 73 |
1 files changed, 50 insertions, 23 deletions
diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c index 9256025d9..f1462eff9 100644 --- a/arch/mips/mm/fault.c +++ b/arch/mips/mm/fault.c @@ -1,10 +1,8 @@ /* * arch/mips/mm/fault.c * - * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds - * Ported to MIPS by Ralf Baechle + * Copyright (C) 1995, 1996 by Ralf Baechle */ -#include <linux/config.h> #include <linux/signal.h> #include <linux/sched.h> #include <linux/head.h> @@ -16,45 +14,47 @@ #include <linux/mman.h> #include <linux/mm.h> +#include <asm/cache.h> #include <asm/system.h> -#include <asm/segment.h> +#include <asm/uaccess.h> #include <asm/pgtable.h> extern void die_if_kernel(char *, struct pt_regs *, long); /* + * Macro for exception fixup code to access integer registers. + */ +#define dpf_reg(r) (regs->regs[r]) + +/* * This routine handles page faults. It determines the address, * and the problem, and then passes it off to one of the appropriate * routines. */ asmlinkage void -do_page_fault(struct pt_regs *regs, unsigned long writeaccess) +do_page_fault(struct pt_regs *regs, unsigned long writeaccess, + unsigned long address) { struct vm_area_struct * vma; - unsigned long address; - - /* get the address */ - __asm__(".set\tmips3\n\t" - "dmfc0\t%0,$8\n\t" - ".set\tmips0" - : "=r" (address)); + struct task_struct *tsk = current; + struct mm_struct *mm = tsk->mm; + unsigned long fixup; #if 0 - printk("do_page_fault() #1: %s %08lx (epc == %08lx)\n", + printk("do_page_fault() #1: %s %08lx (epc == %08lx, ra == %08lx)\n", writeaccess ? "writeaccess to" : "readaccess from", - address, regs->cp0_epc); + address, regs->cp0_epc, regs->regs[31]); #endif - vma = find_vma(current, address); + down(&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 (vma->vm_end - address > current->rlim[RLIMIT_STACK].rlim_cur) + if (expand_stack(vma, address)) goto bad_area; - vma->vm_offset -= vma->vm_start - (address & PAGE_MASK); - vma->vm_start = (address & PAGE_MASK); /* * Ok, we have a good vm_area for this memory access, so * we can handle it.. @@ -68,6 +68,8 @@ good_area: goto bad_area; } handle_mm_fault(vma, address, writeaccess); + up(&mm->mmap_sem); + return; /* @@ -75,18 +77,43 @@ good_area: * Fix it, but check if it's kernel or user first.. */ bad_area: + up(&mm->mmap_sem); + /* Did we have an exception handler installed? */ + + fixup = search_exception_table(regs->cp0_epc); + if (fixup) { + long new_epc; + new_epc = fixup_exception(dpf_reg, fixup, regs->cp0_epc); + printk("Taking exception at %lx (%lx)\n", + regs->cp0_epc, new_epc); + regs->cp0_epc = new_epc; + return; + } if (user_mode(regs)) { - current->tss.cp0_badvaddr = address; - current->tss.error_code = writeaccess; - send_sig(SIGSEGV, current, 1); + tsk->tss.cp0_badvaddr = address; + tsk->tss.error_code = writeaccess; +#if 1 + printk("do_page_fault() #2: sending SIGSEGV to %s for illegal %s\n" + "%08lx (epc == %08lx, ra == %08lx)\n", + tsk->comm, + writeaccess ? "writeaccess to" : "readaccess from", + address, + (unsigned long) regs->cp0_epc, + (unsigned long) regs->regs[31]); +#endif + force_sig(SIGSEGV, tsk); return; } /* * Oops. The kernel tried to access some bad page. We'll have to * terminate things with extreme prejudice. */ - printk(KERN_ALERT "Unable to handle kernel paging request at virtual address %08lx", - address); + printk(KERN_ALERT "Unable to handle kernel paging request at virtual " +#ifdef __mips64 + "address %08lx, epc == %08Lx\n", address, regs->cp0_epc); +#else + "address %08lx, epc == %016lx\n", address, regs->cp0_epc); +#endif die_if_kernel("Oops", regs, writeaccess); do_exit(SIGKILL); } |