diff options
Diffstat (limited to 'arch/xtensa/mm/fault.c')
| -rw-r--r-- | arch/xtensa/mm/fault.c | 81 |
1 files changed, 49 insertions, 32 deletions
diff --git a/arch/xtensa/mm/fault.c b/arch/xtensa/mm/fault.c index a945a33e85a..b57c4f91f48 100644 --- a/arch/xtensa/mm/fault.c +++ b/arch/xtensa/mm/fault.c @@ -6,7 +6,7 @@ * License. See the file "COPYING" in the main directory of this archive * for more details. * - * Copyright (C) 2001 - 2005 Tensilica Inc. + * Copyright (C) 2001 - 2010 Tensilica Inc. * * Chris Zankel <chris@zankel.net> * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> @@ -14,16 +14,18 @@ #include <linux/mm.h> #include <linux/module.h> +#include <linux/hardirq.h> #include <asm/mmu_context.h> #include <asm/cacheflush.h> #include <asm/hardirq.h> #include <asm/uaccess.h> -#include <asm/system.h> #include <asm/pgalloc.h> -unsigned long asid_cache = ASID_FIRST_VERSION; +DEFINE_PER_CPU(unsigned long, asid_cache) = ASID_USER_FIRST; void bad_page_fault(struct pt_regs*, unsigned long, int); +#undef DEBUG_PAGE_FAULT + /* * This routine handles page faults. It determines the address, * and the problem, and then passes it off to one of the appropriate @@ -41,6 +43,8 @@ void do_page_fault(struct pt_regs *regs) siginfo_t info; int is_write, is_exec; + int fault; + unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE; info.si_code = SEGV_MAPERR; @@ -58,16 +62,19 @@ void do_page_fault(struct pt_regs *regs) return; } - is_write = (exccause == XCHAL_EXCCAUSE_STORE_CACHE_ATTRIBUTE) ? 1 : 0; - is_exec = (exccause == XCHAL_EXCCAUSE_ITLB_PRIVILEGE || - exccause == XCHAL_EXCCAUSE_ITLB_MISS || - exccause == XCHAL_EXCCAUSE_FETCH_CACHE_ATTRIBUTE) ? 1 : 0; + is_write = (exccause == EXCCAUSE_STORE_CACHE_ATTRIBUTE) ? 1 : 0; + is_exec = (exccause == EXCCAUSE_ITLB_PRIVILEGE || + exccause == EXCCAUSE_ITLB_MISS || + exccause == EXCCAUSE_FETCH_CACHE_ATTRIBUTE) ? 1 : 0; -#if 0 +#ifdef DEBUG_PAGE_FAULT printk("[%s:%d:%08x:%d:%08x:%s%s]\n", current->comm, current->pid, address, exccause, regs->pc, is_write? "w":"", is_exec? "x":""); #endif + if (user_mode(regs)) + flags |= FAULT_FLAG_USER; +retry: down_read(&mm->mmap_sem); vma = find_vma(mm, address); @@ -90,6 +97,7 @@ good_area: if (is_write) { if (!(vma->vm_flags & VM_WRITE)) goto bad_area; + flags |= FAULT_FLAG_WRITE; } else if (is_exec) { if (!(vma->vm_flags & VM_EXEC)) goto bad_area; @@ -101,21 +109,35 @@ good_area: * make sure we exit gracefully rather than endlessly redo * the fault. */ -survive: - switch (handle_mm_fault(mm, vma, address, is_write)) { - case VM_FAULT_MINOR: - current->min_flt++; - break; - case VM_FAULT_MAJOR: - current->maj_flt++; - break; - case VM_FAULT_SIGBUS: - goto do_sigbus; - case VM_FAULT_OOM: - goto out_of_memory; - default: + 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; + else if (fault & VM_FAULT_SIGBUS) + goto do_sigbus; BUG(); } + if (flags & FAULT_FLAG_ALLOW_RETRY) { + if (fault & VM_FAULT_MAJOR) + current->maj_flt++; + else + current->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; @@ -144,15 +166,10 @@ bad_area: */ out_of_memory: up_read(&mm->mmap_sem); - if (current->pid == 1) { - yield(); - down_read(&mm->mmap_sem); - goto survive; - } - printk("VM: killing process %s\n", current->comm); - if (user_mode(regs)) - do_exit(SIGKILL); - bad_page_fault(regs, address, SIGKILL); + if (!user_mode(regs)) + bad_page_fault(regs, address, SIGKILL); + else + pagefault_out_of_memory(); return; do_sigbus: @@ -171,6 +188,7 @@ do_sigbus: /* Kernel mode? Handle exceptions or die */ if (!user_mode(regs)) bad_page_fault(regs, address, SIGBUS); + return; vmalloc_fault: { @@ -220,7 +238,7 @@ bad_page_fault(struct pt_regs *regs, unsigned long address, int sig) /* Are we prepared to handle this kernel fault? */ if ((entry = search_exception_tables(regs->pc)) != NULL) { -#if 1 +#ifdef DEBUG_PAGE_FAULT printk(KERN_DEBUG "%s: Exception at pc=%#010lx (%lx)\n", current->comm, regs->pc, entry->fixup); #endif @@ -238,4 +256,3 @@ bad_page_fault(struct pt_regs *regs, unsigned long address, int sig) die("Oops", regs, sig); do_exit(sig); } - |