diff options
Diffstat (limited to 'arch/sh/mm/fault_32.c')
| -rw-r--r-- | arch/sh/mm/fault_32.c | 74 |
1 files changed, 44 insertions, 30 deletions
diff --git a/arch/sh/mm/fault_32.c b/arch/sh/mm/fault_32.c index 0c776fdfbdd..31a33ebdef6 100644 --- a/arch/sh/mm/fault_32.c +++ b/arch/sh/mm/fault_32.c @@ -2,7 +2,7 @@ * Page fault handler for SH with an MMU. * * Copyright (C) 1999 Niibe Yutaka - * Copyright (C) 2003 - 2007 Paul Mundt + * Copyright (C) 2003 - 2008 Paul Mundt * * Based on linux/arch/i386/mm/fault.c: * Copyright (C) 1995 Linus Torvalds @@ -15,11 +15,11 @@ #include <linux/mm.h> #include <linux/hardirq.h> #include <linux/kprobes.h> +#include <linux/marker.h> #include <asm/io_trapped.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, @@ -37,10 +37,10 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, int fault; siginfo_t info; -#ifdef CONFIG_SH_KGDB - if (kgdb_nofault && kgdb_bus_err_hook) - kgdb_bus_err_hook(); -#endif + /* + * We don't bother with any notifier callbacks here, as they are + * all handled through the __do_page_fault() fast-path. + */ tsk = current; si_code = SEGV_MAPERR; @@ -61,7 +61,6 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, 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; @@ -71,9 +70,13 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, 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); + + if (!pud_present(*pud)) { + if (!pud_present(*pud_k)) + goto bad_area_nosemaphore; + set_pud(pud, *pud_k); + return; + } pmd = pmd_offset(pud, address); pmd_k = pmd_offset(pud_k, address); @@ -242,17 +245,25 @@ do_sigbus: 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 +static inline int notify_page_fault(struct pt_regs *regs, int trap) +{ + int ret = 0; + + trace_mark(kernel_arch_trap_entry, "trap_id %d ip #p%ld", + trap >> 5, instruction_pointer(regs)); + +#ifdef CONFIG_KPROBES + if (!user_mode(regs)) { + preempt_disable(); + if (kprobe_running() && kprobe_fault_handler(regs, trap)) + ret = 1; + preempt_enable(); + } #endif + return ret; +} + /* * Called with interrupts disabled. */ @@ -265,11 +276,12 @@ asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs, pmd_t *pmd; pte_t *pte; pte_t entry; + int ret = 0; -#ifdef CONFIG_SH_KGDB - if (kgdb_nofault && kgdb_bus_err_hook) - kgdb_bus_err_hook(); -#endif + if (notify_page_fault(regs, lookup_exception_vector())) + goto out; + + ret = 1; /* * We don't take page faults for P1, P2, and parts of P4, these @@ -280,24 +292,23 @@ asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs, pgd = pgd_offset_k(address); } else { if (unlikely(address >= TASK_SIZE || !current->mm)) - return 1; + goto out; pgd = pgd_offset(current->mm, address); } pud = pud_offset(pgd, address); if (pud_none_or_clear_bad(pud)) - return 1; + goto out; pmd = pmd_offset(pud, address); if (pmd_none_or_clear_bad(pmd)) - return 1; - + goto out; pte = pte_offset_kernel(pmd, address); entry = *pte; if (unlikely(pte_none(entry) || pte_not_present(entry))) - return 1; + goto out; if (unlikely(writeaccess && !pte_write(entry))) - return 1; + goto out; if (writeaccess) entry = pte_mkdirty(entry); @@ -314,5 +325,8 @@ asmlinkage int __kprobes __do_page_fault(struct pt_regs *regs, set_pte(pte, entry); update_mmu_cache(NULL, address, entry); - return 0; + ret = 0; +out: + trace_mark(kernel_arch_trap_exit, MARK_NOARGS); + return ret; } |