diff options
Diffstat (limited to 'arch/cris/mm/fault.c')
| -rw-r--r-- | arch/cris/mm/fault.c | 80 |
1 files changed, 59 insertions, 21 deletions
diff --git a/arch/cris/mm/fault.c b/arch/cris/mm/fault.c index 380df1a73a6..1790f22e71a 100644 --- a/arch/cris/mm/fault.c +++ b/arch/cris/mm/fault.c @@ -1,19 +1,19 @@ /* - * linux/arch/cris/mm/fault.c - * - * Copyright (C) 2000-2006 Axis Communications AB - * - * Authors: Bjorn Wesen + * arch/cris/mm/fault.c * + * Copyright (C) 2000-2010 Axis Communications AB */ #include <linux/mm.h> #include <linux/interrupt.h> #include <linux/module.h> +#include <linux/wait.h> #include <asm/uaccess.h> +#include <arch/system.h> extern int find_fixup_code(struct pt_regs *); extern void die_if_kernel(const char *, struct pt_regs *, long); +extern void show_registers(struct pt_regs *regs); /* debug of low-level TLB reload */ #undef DEBUG @@ -58,6 +58,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs, struct vm_area_struct * vma; siginfo_t info; int fault; + unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; D(printk(KERN_DEBUG "Page fault for %lX on %X at %lX, prot %d write %d\n", @@ -108,13 +109,16 @@ do_page_fault(unsigned long address, struct pt_regs *regs, info.si_code = SEGV_MAPERR; /* - * If we're in an interrupt or have no user - * context, we must not take the fault.. + * If we're in an interrupt or "atomic" operation or have no + * user context, we must not take the fault. */ - if (in_interrupt() || !mm) + if (in_atomic() || !mm) goto no_context; + if (user_mode(regs)) + flags |= FAULT_FLAG_USER; +retry: down_read(&mm->mmap_sem); vma = find_vma(mm, address); if (!vma) @@ -152,6 +156,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs, } else if (writeaccess == 1) { if (!(vma->vm_flags & VM_WRITE)) goto bad_area; + flags |= FAULT_FLAG_WRITE; } else { if (!(vma->vm_flags & (VM_READ | VM_EXEC))) goto bad_area; @@ -163,7 +168,11 @@ do_page_fault(unsigned long address, struct pt_regs *regs, * the fault. */ - fault = handle_mm_fault(mm, vma, address, (writeaccess & 1) ? FAULT_FLAG_WRITE : 0); + fault = handle_mm_fault(mm, vma, address, flags); + + if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) + return; + if (unlikely(fault & VM_FAULT_ERROR)) { if (fault & VM_FAULT_OOM) goto out_of_memory; @@ -171,10 +180,25 @@ do_page_fault(unsigned long address, struct pt_regs *regs, goto do_sigbus; BUG(); } - if (fault & VM_FAULT_MAJOR) - tsk->maj_flt++; - else - tsk->min_flt++; + + if (flags & FAULT_FLAG_ALLOW_RETRY) { + if (fault & VM_FAULT_MAJOR) + tsk->maj_flt++; + else + tsk->min_flt++; + if (fault & VM_FAULT_RETRY) { + flags &= ~FAULT_FLAG_ALLOW_RETRY; + flags |= FAULT_FLAG_TRIED; + + /* + * No need to up_read(&mm->mmap_sem) as we would + * have already released it in __lock_page_or_retry + * in mm/filemap.c. + */ + + goto retry; + } + } up_read(&mm->mmap_sem); return; @@ -193,14 +217,25 @@ do_page_fault(unsigned long address, struct pt_regs *regs, /* User mode accesses just cause a SIGSEGV */ if (user_mode(regs)) { + printk(KERN_NOTICE "%s (pid %d) segfaults for page " + "address %08lx at pc %08lx\n", + tsk->comm, tsk->pid, + address, instruction_pointer(regs)); + + /* With DPG on, we've already dumped registers above. */ + DPG(if (0)) + show_registers(regs); + +#ifdef CONFIG_NO_SEGFAULT_TERMINATION + DECLARE_WAIT_QUEUE_HEAD(wq); + wait_event_interruptible(wq, 0 == 1); +#else info.si_signo = SIGSEGV; info.si_errno = 0; /* info.si_code has been set above */ info.si_addr = (void *)address; force_sig_info(SIGSEGV, &info, tsk); - printk(KERN_NOTICE "%s (pid %d) segfaults for page " - "address %08lx at pc %08lx\n", - tsk->comm, tsk->pid, address, instruction_pointer(regs)); +#endif return; } @@ -245,10 +280,10 @@ do_page_fault(unsigned long address, struct pt_regs *regs, out_of_memory: up_read(&mm->mmap_sem); - printk("VM: killing process %s\n", tsk->comm); - if (user_mode(regs)) - do_exit(SIGKILL); - goto no_context; + if (!user_mode(regs)) + goto no_context; + pagefault_out_of_memory(); + return; do_sigbus: up_read(&mm->mmap_sem); @@ -334,8 +369,11 @@ int find_fixup_code(struct pt_regs *regs) { const struct exception_table_entry *fixup; + /* in case of delay slot fault (v32) */ + unsigned long ip = (instruction_pointer(regs) & ~0x1); - if ((fixup = search_exception_tables(instruction_pointer(regs))) != 0) { + fixup = search_exception_tables(ip); + if (fixup != 0) { /* Adjust the instruction pointer in the stackframe. */ instruction_pointer(regs) = fixup->fixup; arch_fixup(regs); |