1eeb66a1bb
This patch moves the die notifier handling to common code. Previous various architectures had exactly the same code for it. Note that the new code is compiled unconditionally, this should be understood as an appel to the other architecture maintainer to implement support for it aswell (aka sprinkling a notify_die or two in the proper place) arm had a notifiy_die that did something totally different, I renamed it to arm_notify_die as part of the patch and made it static to the file it's declared and used at. avr32 used to pass slightly less information through this interface and I brought it into line with the other architectures. [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: fix vmalloc_sync_all bustage] [bryan.wu@analog.com: fix vmalloc_sync_all in nommu] Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: <linux-arch@vger.kernel.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Bryan Wu <bryan.wu@analog.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
594 lines
15 KiB
C
594 lines
15 KiB
C
/* $Id: fault.c,v 1.122 2001/11/17 07:19:26 davem Exp $
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* fault.c: Page fault handlers for the Sparc.
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*
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* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
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* Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
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* Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
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*/
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#include <asm/head.h>
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#include <linux/string.h>
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#include <linux/types.h>
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#include <linux/sched.h>
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#include <linux/ptrace.h>
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#include <linux/mman.h>
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#include <linux/threads.h>
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#include <linux/kernel.h>
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#include <linux/signal.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/smp_lock.h>
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#include <linux/interrupt.h>
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#include <linux/module.h>
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#include <linux/kdebug.h>
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#include <asm/system.h>
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#include <asm/page.h>
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#include <asm/pgtable.h>
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#include <asm/memreg.h>
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#include <asm/openprom.h>
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#include <asm/oplib.h>
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#include <asm/smp.h>
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#include <asm/traps.h>
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#include <asm/uaccess.h>
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extern int prom_node_root;
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/* At boot time we determine these two values necessary for setting
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* up the segment maps and page table entries (pte's).
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*/
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int num_segmaps, num_contexts;
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int invalid_segment;
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/* various Virtual Address Cache parameters we find at boot time... */
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int vac_size, vac_linesize, vac_do_hw_vac_flushes;
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int vac_entries_per_context, vac_entries_per_segment;
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int vac_entries_per_page;
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/* Nice, simple, prom library does all the sweating for us. ;) */
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int prom_probe_memory (void)
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{
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register struct linux_mlist_v0 *mlist;
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register unsigned long bytes, base_paddr, tally;
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register int i;
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i = 0;
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mlist= *prom_meminfo()->v0_available;
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bytes = tally = mlist->num_bytes;
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base_paddr = (unsigned long) mlist->start_adr;
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sp_banks[0].base_addr = base_paddr;
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sp_banks[0].num_bytes = bytes;
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while (mlist->theres_more != (void *) 0){
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i++;
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mlist = mlist->theres_more;
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bytes = mlist->num_bytes;
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tally += bytes;
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if (i > SPARC_PHYS_BANKS-1) {
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printk ("The machine has more banks than "
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"this kernel can support\n"
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"Increase the SPARC_PHYS_BANKS "
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"setting (currently %d)\n",
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SPARC_PHYS_BANKS);
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i = SPARC_PHYS_BANKS-1;
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break;
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}
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sp_banks[i].base_addr = (unsigned long) mlist->start_adr;
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sp_banks[i].num_bytes = mlist->num_bytes;
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}
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i++;
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sp_banks[i].base_addr = 0xdeadbeef;
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sp_banks[i].num_bytes = 0;
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/* Now mask all bank sizes on a page boundary, it is all we can
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* use anyways.
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*/
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for(i=0; sp_banks[i].num_bytes != 0; i++)
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sp_banks[i].num_bytes &= PAGE_MASK;
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return tally;
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}
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/* Traverse the memory lists in the prom to see how much physical we
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* have.
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*/
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unsigned long
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probe_memory(void)
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{
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int total;
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total = prom_probe_memory();
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/* Oh man, much nicer, keep the dirt in promlib. */
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return total;
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}
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extern void sun4c_complete_all_stores(void);
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/* Whee, a level 15 NMI interrupt memory error. Let's have fun... */
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asmlinkage void sparc_lvl15_nmi(struct pt_regs *regs, unsigned long serr,
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unsigned long svaddr, unsigned long aerr,
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unsigned long avaddr)
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{
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sun4c_complete_all_stores();
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printk("FAULT: NMI received\n");
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printk("SREGS: Synchronous Error %08lx\n", serr);
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printk(" Synchronous Vaddr %08lx\n", svaddr);
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printk(" Asynchronous Error %08lx\n", aerr);
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printk(" Asynchronous Vaddr %08lx\n", avaddr);
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if (sun4c_memerr_reg)
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printk(" Memory Parity Error %08lx\n", *sun4c_memerr_reg);
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printk("REGISTER DUMP:\n");
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show_regs(regs);
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prom_halt();
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}
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static void unhandled_fault(unsigned long, struct task_struct *,
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struct pt_regs *) __attribute__ ((noreturn));
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static void unhandled_fault(unsigned long address, struct task_struct *tsk,
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struct pt_regs *regs)
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{
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if((unsigned long) address < PAGE_SIZE) {
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printk(KERN_ALERT
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"Unable to handle kernel NULL pointer dereference\n");
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} else {
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printk(KERN_ALERT "Unable to handle kernel paging request "
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"at virtual address %08lx\n", address);
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}
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printk(KERN_ALERT "tsk->{mm,active_mm}->context = %08lx\n",
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(tsk->mm ? tsk->mm->context : tsk->active_mm->context));
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printk(KERN_ALERT "tsk->{mm,active_mm}->pgd = %08lx\n",
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(tsk->mm ? (unsigned long) tsk->mm->pgd :
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(unsigned long) tsk->active_mm->pgd));
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die_if_kernel("Oops", regs);
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}
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asmlinkage int lookup_fault(unsigned long pc, unsigned long ret_pc,
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unsigned long address)
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{
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struct pt_regs regs;
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unsigned long g2;
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unsigned int insn;
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int i;
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i = search_extables_range(ret_pc, &g2);
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switch (i) {
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case 3:
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/* load & store will be handled by fixup */
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return 3;
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case 1:
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/* store will be handled by fixup, load will bump out */
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/* for _to_ macros */
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insn = *((unsigned int *) pc);
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if ((insn >> 21) & 1)
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return 1;
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break;
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case 2:
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/* load will be handled by fixup, store will bump out */
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/* for _from_ macros */
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insn = *((unsigned int *) pc);
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if (!((insn >> 21) & 1) || ((insn>>19)&0x3f) == 15)
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return 2;
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break;
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default:
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break;
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};
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memset(®s, 0, sizeof (regs));
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regs.pc = pc;
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regs.npc = pc + 4;
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__asm__ __volatile__(
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"rd %%psr, %0\n\t"
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"nop\n\t"
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"nop\n\t"
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"nop\n" : "=r" (regs.psr));
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unhandled_fault(address, current, ®s);
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/* Not reached */
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return 0;
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}
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extern unsigned long safe_compute_effective_address(struct pt_regs *,
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unsigned int);
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static unsigned long compute_si_addr(struct pt_regs *regs, int text_fault)
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{
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unsigned int insn;
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if (text_fault)
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return regs->pc;
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if (regs->psr & PSR_PS) {
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insn = *(unsigned int *) regs->pc;
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} else {
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__get_user(insn, (unsigned int *) regs->pc);
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}
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return safe_compute_effective_address(regs, insn);
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}
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asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
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unsigned long address)
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{
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struct vm_area_struct *vma;
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struct task_struct *tsk = current;
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struct mm_struct *mm = tsk->mm;
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unsigned int fixup;
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unsigned long g2;
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siginfo_t info;
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int from_user = !(regs->psr & PSR_PS);
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if(text_fault)
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address = regs->pc;
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/*
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* We fault-in kernel-space virtual memory on-demand. The
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* 'reference' page table is init_mm.pgd.
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*
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* NOTE! We MUST NOT take any locks for this case. We may
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* be in an interrupt or a critical region, and should
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* only copy the information from the master page table,
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* nothing more.
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*/
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if (!ARCH_SUN4C_SUN4 && address >= TASK_SIZE)
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goto vmalloc_fault;
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info.si_code = SEGV_MAPERR;
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/*
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* If we're in an interrupt or have no user
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* context, we must not take the fault..
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*/
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if (in_atomic() || !mm)
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goto no_context;
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down_read(&mm->mmap_sem);
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/*
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* The kernel referencing a bad kernel pointer can lock up
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* a sun4c machine completely, so we must attempt recovery.
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*/
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if(!from_user && address >= PAGE_OFFSET)
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goto bad_area;
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vma = find_vma(mm, address);
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if(!vma)
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goto bad_area;
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if(vma->vm_start <= address)
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goto good_area;
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if(!(vma->vm_flags & VM_GROWSDOWN))
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goto bad_area;
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if(expand_stack(vma, address))
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goto bad_area;
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/*
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* Ok, we have a good vm_area for this memory access, so
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* we can handle it..
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*/
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good_area:
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info.si_code = SEGV_ACCERR;
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if(write) {
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if(!(vma->vm_flags & VM_WRITE))
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goto bad_area;
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} else {
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/* Allow reads even for write-only mappings */
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if(!(vma->vm_flags & (VM_READ | VM_EXEC)))
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goto bad_area;
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}
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/*
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* If for any reason at all we couldn't handle the fault,
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* make sure we exit gracefully rather than endlessly redo
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* the fault.
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*/
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switch (handle_mm_fault(mm, vma, address, write)) {
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case VM_FAULT_SIGBUS:
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goto do_sigbus;
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case VM_FAULT_OOM:
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goto out_of_memory;
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case VM_FAULT_MAJOR:
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current->maj_flt++;
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break;
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case VM_FAULT_MINOR:
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default:
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current->min_flt++;
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break;
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}
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up_read(&mm->mmap_sem);
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return;
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/*
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* Something tried to access memory that isn't in our memory map..
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* Fix it, but check if it's kernel or user first..
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*/
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bad_area:
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up_read(&mm->mmap_sem);
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bad_area_nosemaphore:
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/* User mode accesses just cause a SIGSEGV */
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if(from_user) {
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#if 0
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printk("Fault whee %s [%d]: segfaults at %08lx pc=%08lx\n",
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tsk->comm, tsk->pid, address, regs->pc);
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#endif
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info.si_signo = SIGSEGV;
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info.si_errno = 0;
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/* info.si_code set above to make clear whether
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this was a SEGV_MAPERR or SEGV_ACCERR fault. */
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info.si_addr = (void __user *)compute_si_addr(regs, text_fault);
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info.si_trapno = 0;
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force_sig_info (SIGSEGV, &info, tsk);
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return;
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}
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/* Is this in ex_table? */
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no_context:
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g2 = regs->u_regs[UREG_G2];
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if (!from_user && (fixup = search_extables_range(regs->pc, &g2))) {
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if (fixup > 10) { /* Values below are reserved for other things */
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extern const unsigned __memset_start[];
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extern const unsigned __memset_end[];
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extern const unsigned __csum_partial_copy_start[];
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extern const unsigned __csum_partial_copy_end[];
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#ifdef DEBUG_EXCEPTIONS
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printk("Exception: PC<%08lx> faddr<%08lx>\n", regs->pc, address);
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printk("EX_TABLE: insn<%08lx> fixup<%08x> g2<%08lx>\n",
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regs->pc, fixup, g2);
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#endif
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if ((regs->pc >= (unsigned long)__memset_start &&
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regs->pc < (unsigned long)__memset_end) ||
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(regs->pc >= (unsigned long)__csum_partial_copy_start &&
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regs->pc < (unsigned long)__csum_partial_copy_end)) {
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regs->u_regs[UREG_I4] = address;
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regs->u_regs[UREG_I5] = regs->pc;
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}
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regs->u_regs[UREG_G2] = g2;
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regs->pc = fixup;
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regs->npc = regs->pc + 4;
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return;
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}
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}
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unhandled_fault (address, tsk, regs);
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do_exit(SIGKILL);
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/*
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* We ran out of memory, or some other thing happened to us that made
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* us unable to handle the page fault gracefully.
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*/
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out_of_memory:
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up_read(&mm->mmap_sem);
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printk("VM: killing process %s\n", tsk->comm);
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if (from_user)
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do_exit(SIGKILL);
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goto no_context;
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do_sigbus:
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up_read(&mm->mmap_sem);
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info.si_signo = SIGBUS;
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info.si_errno = 0;
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info.si_code = BUS_ADRERR;
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info.si_addr = (void __user *) compute_si_addr(regs, text_fault);
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info.si_trapno = 0;
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force_sig_info (SIGBUS, &info, tsk);
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if (!from_user)
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goto no_context;
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vmalloc_fault:
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{
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/*
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* Synchronize this task's top level page-table
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* with the 'reference' page table.
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*/
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int offset = pgd_index(address);
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pgd_t *pgd, *pgd_k;
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pmd_t *pmd, *pmd_k;
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pgd = tsk->active_mm->pgd + offset;
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pgd_k = init_mm.pgd + offset;
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if (!pgd_present(*pgd)) {
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if (!pgd_present(*pgd_k))
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goto bad_area_nosemaphore;
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pgd_val(*pgd) = pgd_val(*pgd_k);
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return;
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}
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pmd = pmd_offset(pgd, address);
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pmd_k = pmd_offset(pgd_k, address);
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if (pmd_present(*pmd) || !pmd_present(*pmd_k))
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goto bad_area_nosemaphore;
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*pmd = *pmd_k;
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return;
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}
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}
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asmlinkage void do_sun4c_fault(struct pt_regs *regs, int text_fault, int write,
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unsigned long address)
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{
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extern void sun4c_update_mmu_cache(struct vm_area_struct *,
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unsigned long,pte_t);
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extern pte_t *sun4c_pte_offset_kernel(pmd_t *,unsigned long);
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struct task_struct *tsk = current;
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struct mm_struct *mm = tsk->mm;
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pgd_t *pgdp;
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pte_t *ptep;
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if (text_fault) {
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address = regs->pc;
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} else if (!write &&
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!(regs->psr & PSR_PS)) {
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unsigned int insn, __user *ip;
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ip = (unsigned int __user *)regs->pc;
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if (!get_user(insn, ip)) {
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if ((insn & 0xc1680000) == 0xc0680000)
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write = 1;
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}
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}
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if (!mm) {
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/* We are oopsing. */
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do_sparc_fault(regs, text_fault, write, address);
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BUG(); /* P3 Oops already, you bitch */
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}
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pgdp = pgd_offset(mm, address);
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ptep = sun4c_pte_offset_kernel((pmd_t *) pgdp, address);
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if (pgd_val(*pgdp)) {
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if (write) {
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if ((pte_val(*ptep) & (_SUN4C_PAGE_WRITE|_SUN4C_PAGE_PRESENT))
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== (_SUN4C_PAGE_WRITE|_SUN4C_PAGE_PRESENT)) {
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unsigned long flags;
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*ptep = __pte(pte_val(*ptep) | _SUN4C_PAGE_ACCESSED |
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_SUN4C_PAGE_MODIFIED |
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_SUN4C_PAGE_VALID |
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_SUN4C_PAGE_DIRTY);
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local_irq_save(flags);
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if (sun4c_get_segmap(address) != invalid_segment) {
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sun4c_put_pte(address, pte_val(*ptep));
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local_irq_restore(flags);
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return;
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}
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local_irq_restore(flags);
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}
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} else {
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if ((pte_val(*ptep) & (_SUN4C_PAGE_READ|_SUN4C_PAGE_PRESENT))
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== (_SUN4C_PAGE_READ|_SUN4C_PAGE_PRESENT)) {
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unsigned long flags;
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*ptep = __pte(pte_val(*ptep) | _SUN4C_PAGE_ACCESSED |
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_SUN4C_PAGE_VALID);
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local_irq_save(flags);
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if (sun4c_get_segmap(address) != invalid_segment) {
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sun4c_put_pte(address, pte_val(*ptep));
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local_irq_restore(flags);
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return;
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}
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local_irq_restore(flags);
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}
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}
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}
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/* This conditional is 'interesting'. */
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if (pgd_val(*pgdp) && !(write && !(pte_val(*ptep) & _SUN4C_PAGE_WRITE))
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&& (pte_val(*ptep) & _SUN4C_PAGE_VALID))
|
|
/* Note: It is safe to not grab the MMAP semaphore here because
|
|
* we know that update_mmu_cache() will not sleep for
|
|
* any reason (at least not in the current implementation)
|
|
* and therefore there is no danger of another thread getting
|
|
* on the CPU and doing a shrink_mmap() on this vma.
|
|
*/
|
|
sun4c_update_mmu_cache (find_vma(current->mm, address), address,
|
|
*ptep);
|
|
else
|
|
do_sparc_fault(regs, text_fault, write, address);
|
|
}
|
|
|
|
/* This always deals with user addresses. */
|
|
inline void force_user_fault(unsigned long address, int write)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
struct task_struct *tsk = current;
|
|
struct mm_struct *mm = tsk->mm;
|
|
siginfo_t info;
|
|
|
|
info.si_code = SEGV_MAPERR;
|
|
|
|
#if 0
|
|
printk("wf<pid=%d,wr=%d,addr=%08lx>\n",
|
|
tsk->pid, write, address);
|
|
#endif
|
|
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(expand_stack(vma, address))
|
|
goto bad_area;
|
|
good_area:
|
|
info.si_code = SEGV_ACCERR;
|
|
if(write) {
|
|
if(!(vma->vm_flags & VM_WRITE))
|
|
goto bad_area;
|
|
} else {
|
|
if(!(vma->vm_flags & (VM_READ | VM_EXEC)))
|
|
goto bad_area;
|
|
}
|
|
switch (handle_mm_fault(mm, vma, address, write)) {
|
|
case VM_FAULT_SIGBUS:
|
|
case VM_FAULT_OOM:
|
|
goto do_sigbus;
|
|
}
|
|
up_read(&mm->mmap_sem);
|
|
return;
|
|
bad_area:
|
|
up_read(&mm->mmap_sem);
|
|
#if 0
|
|
printk("Window whee %s [%d]: segfaults at %08lx\n",
|
|
tsk->comm, tsk->pid, address);
|
|
#endif
|
|
info.si_signo = SIGSEGV;
|
|
info.si_errno = 0;
|
|
/* info.si_code set above to make clear whether
|
|
this was a SEGV_MAPERR or SEGV_ACCERR fault. */
|
|
info.si_addr = (void __user *) address;
|
|
info.si_trapno = 0;
|
|
force_sig_info (SIGSEGV, &info, tsk);
|
|
return;
|
|
|
|
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;
|
|
info.si_trapno = 0;
|
|
force_sig_info (SIGBUS, &info, tsk);
|
|
}
|
|
|
|
void window_overflow_fault(void)
|
|
{
|
|
unsigned long sp;
|
|
|
|
sp = current_thread_info()->rwbuf_stkptrs[0];
|
|
if(((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK))
|
|
force_user_fault(sp + 0x38, 1);
|
|
force_user_fault(sp, 1);
|
|
}
|
|
|
|
void window_underflow_fault(unsigned long sp)
|
|
{
|
|
if(((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK))
|
|
force_user_fault(sp + 0x38, 0);
|
|
force_user_fault(sp, 0);
|
|
}
|
|
|
|
void window_ret_fault(struct pt_regs *regs)
|
|
{
|
|
unsigned long sp;
|
|
|
|
sp = regs->u_regs[UREG_FP];
|
|
if(((sp + 0x38) & PAGE_MASK) != (sp & PAGE_MASK))
|
|
force_user_fault(sp + 0x38, 0);
|
|
force_user_fault(sp, 0);
|
|
}
|