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author | Paul Mundt <lethal@linux-sh.org> | 2007-11-20 17:01:55 +0900 |
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committer | Paul Mundt <lethal@linux-sh.org> | 2008-01-28 13:18:50 +0900 |
commit | 811d50cb43eb730cc325df0c6913556e25739797 (patch) | |
tree | c62c7ec9d53b4ad3357251bfae0c28f6fb2d773d /arch/sh/mm/fault.c | |
parent | 379a95d1d2c3e3682e380084c40b6fc01e38fa1f (diff) | |
download | lwn-811d50cb43eb730cc325df0c6913556e25739797.tar.gz lwn-811d50cb43eb730cc325df0c6913556e25739797.zip |
sh: Move in the SH-5 TLB miss.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/mm/fault.c')
-rw-r--r-- | arch/sh/mm/fault.c | 303 |
1 files changed, 0 insertions, 303 deletions
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c deleted file mode 100644 index 60d74f793a1d..000000000000 --- a/arch/sh/mm/fault.c +++ /dev/null @@ -1,303 +0,0 @@ -/* - * Page fault handler for SH with an MMU. - * - * Copyright (C) 1999 Niibe Yutaka - * Copyright (C) 2003 - 2007 Paul Mundt - * - * Based on linux/arch/i386/mm/fault.c: - * Copyright (C) 1995 Linus Torvalds - * - * 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/kernel.h> -#include <linux/mm.h> -#include <linux/hardirq.h> -#include <linux/kprobes.h> -#include <asm/system.h> -#include <asm/mmu_context.h> -#include <asm/tlbflush.h> -#include <asm/kgdb.h> - -/* - * 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 __kprobes do_page_fault(struct pt_regs *regs, - unsigned long writeaccess, - unsigned long address) -{ - struct task_struct *tsk; - struct mm_struct *mm; - struct vm_area_struct * vma; - int si_code; - int fault; - siginfo_t info; - - trace_hardirqs_on(); - local_irq_enable(); - -#ifdef CONFIG_SH_KGDB - if (kgdb_nofault && kgdb_bus_err_hook) - kgdb_bus_err_hook(); -#endif - - tsk = current; - mm = tsk->mm; - si_code = SEGV_MAPERR; - - if (unlikely(address >= TASK_SIZE)) { - /* - * Synchronize this task's top level page-table - * with the 'reference' page table. - * - * Do _not_ use "tsk" here. We might be inside - * an interrupt in the middle of a task switch.. - */ - int offset = pgd_index(address); - pgd_t *pgd, *pgd_k; - pud_t *pud, *pud_k; - pmd_t *pmd, *pmd_k; - - pgd = get_TTB() + offset; - pgd_k = swapper_pg_dir + offset; - - /* This will never happen with the folded page table. */ - if (!pgd_present(*pgd)) { - if (!pgd_present(*pgd_k)) - goto bad_area_nosemaphore; - set_pgd(pgd, *pgd_k); - return; - } - - pud = pud_offset(pgd, address); - pud_k = pud_offset(pgd_k, address); - if (pud_present(*pud) || !pud_present(*pud_k)) - goto bad_area_nosemaphore; - set_pud(pud, *pud_k); - - pmd = pmd_offset(pud, address); - pmd_k = pmd_offset(pud_k, address); - if (pmd_present(*pmd) || !pmd_present(*pmd_k)) - goto bad_area_nosemaphore; - set_pmd(pmd, *pmd_k); - - return; - } - - /* - * If we're in an interrupt or have no user - * context, we must not take the fault.. - */ - if (in_atomic() || !mm) - goto no_context; - - 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; -/* - * Ok, we have a good vm_area for this memory access, so - * we can handle it.. - */ -good_area: - si_code = SEGV_ACCERR; - if (writeaccess) { - if (!(vma->vm_flags & VM_WRITE)) - goto bad_area; - } else { - 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, writeaccess); - 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) - tsk->maj_flt++; - else - tsk->min_flt++; - - up_read(&mm->mmap_sem); - return; - -/* - * Something tried to access memory that isn't in our memory map.. - * Fix it, but check if it's kernel or user first.. - */ -bad_area: - up_read(&mm->mmap_sem); - -bad_area_nosemaphore: - if (user_mode(regs)) { - info.si_signo = SIGSEGV; - info.si_errno = 0; - info.si_code = si_code; - info.si_addr = (void *) address; - force_sig_info(SIGSEGV, &info, tsk); - return; - } - -no_context: - /* Are we prepared to handle this kernel fault? */ - if (fixup_exception(regs)) - return; - -/* - * Oops. The kernel tried to access some bad page. We'll have to - * terminate things with extreme prejudice. - * - */ - - bust_spinlocks(1); - - if (oops_may_print()) { - __typeof__(pte_val(__pte(0))) page; - - if (address < PAGE_SIZE) - printk(KERN_ALERT "Unable to handle kernel NULL " - "pointer dereference"); - else - printk(KERN_ALERT "Unable to handle kernel paging " - "request"); - printk(" at virtual address %08lx\n", address); - printk(KERN_ALERT "pc = %08lx\n", regs->pc); - page = (unsigned long)get_TTB(); - if (page) { - page = ((__typeof__(page) *)page)[address >> PGDIR_SHIFT]; - printk(KERN_ALERT "*pde = %08lx\n", page); - if (page & _PAGE_PRESENT) { - page &= PAGE_MASK; - address &= 0x003ff000; - page = ((__typeof__(page) *) - __va(page))[address >> - PAGE_SHIFT]; - printk(KERN_ALERT "*pte = %08lx\n", page); - } - } - } - - die("Oops", regs, writeaccess); - bust_spinlocks(0); - do_exit(SIGKILL); - -/* - * 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", tsk->comm); - if (user_mode(regs)) - do_group_exit(SIGKILL); - goto no_context; - -do_sigbus: - up_read(&mm->mmap_sem); - - /* - * Send a sigbus, regardless of whether we were in kernel - * or user mode. - */ - info.si_signo = SIGBUS; - info.si_errno = 0; - info.si_code = BUS_ADRERR; - info.si_addr = (void *)address; - force_sig_info(SIGBUS, &info, tsk); - - /* Kernel mode? Handle exceptions or die */ - if (!user_mode(regs)) - goto no_context; -} - -#ifdef CONFIG_SH_STORE_QUEUES -/* - * This is a special case for the SH-4 store queues, as pages for this - * space still need to be faulted in before it's possible to flush the - * store queue cache for writeout to the remapped region. - */ -#define P3_ADDR_MAX (P4SEG_STORE_QUE + 0x04000000) -#else -#define P3_ADDR_MAX P4SEG -#endif - -/* - * Called with interrupts disabled. - */ -asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs, - unsigned long writeaccess, - unsigned long address) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - pte_t entry; - -#ifdef CONFIG_SH_KGDB - if (kgdb_nofault && kgdb_bus_err_hook) - kgdb_bus_err_hook(); -#endif - - /* - * We don't take page faults for P1, P2, and parts of P4, these - * are always mapped, whether it be due to legacy behaviour in - * 29-bit mode, or due to PMB configuration in 32-bit mode. - */ - if (address >= P3SEG && address < P3_ADDR_MAX) { - 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_or_clear_bad(pud)) - return 1; - pmd = pmd_offset(pud, address); - if (pmd_none_or_clear_bad(pmd)) - return 1; - - pte = pte_offset_kernel(pmd, address); - entry = *pte; - if (unlikely(pte_none(entry) || pte_not_present(entry))) - return 1; - if (unlikely(writeaccess && !pte_write(entry))) - return 1; - - if (writeaccess) - entry = pte_mkdirty(entry); - entry = pte_mkyoung(entry); - - set_pte(pte, entry); - update_mmu_cache(NULL, address, entry); - - return 0; -} |