| /* |
| * SPU mm fault handler |
| * |
| * (C) Copyright IBM Deutschland Entwicklung GmbH 2007 |
| * |
| * Author: Arnd Bergmann <[email protected]> |
| * Author: Jeremy Kerr <[email protected]> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2, or (at your option) |
| * any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| #include <linux/sched.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| |
| #include <asm/spu.h> |
| #include <asm/spu_csa.h> |
| |
| /* |
| * This ought to be kept in sync with the powerpc specific do_page_fault |
| * function. Currently, there are a few corner cases that we haven't had |
| * to handle fortunately. |
| */ |
| int spu_handle_mm_fault(struct mm_struct *mm, unsigned long ea, |
| unsigned long dsisr, unsigned *flt) |
| { |
| struct vm_area_struct *vma; |
| unsigned long is_write; |
| int ret; |
| |
| if (mm == NULL) |
| return -EFAULT; |
| |
| if (mm->pgd == NULL) |
| return -EFAULT; |
| |
| down_read(&mm->mmap_sem); |
| ret = -EFAULT; |
| vma = find_vma(mm, ea); |
| if (!vma) |
| goto out_unlock; |
| |
| if (ea < vma->vm_start) { |
| if (!(vma->vm_flags & VM_GROWSDOWN)) |
| goto out_unlock; |
| if (expand_stack(vma, ea)) |
| goto out_unlock; |
| } |
| |
| is_write = dsisr & MFC_DSISR_ACCESS_PUT; |
| if (is_write) { |
| if (!(vma->vm_flags & VM_WRITE)) |
| goto out_unlock; |
| } else { |
| if (dsisr & MFC_DSISR_ACCESS_DENIED) |
| goto out_unlock; |
| if (!(vma->vm_flags & (VM_READ | VM_EXEC))) |
| goto out_unlock; |
| } |
| |
| ret = 0; |
| *flt = handle_mm_fault(mm, vma, ea, is_write ? FAULT_FLAG_WRITE : 0); |
| if (unlikely(*flt & VM_FAULT_ERROR)) { |
| if (*flt & VM_FAULT_OOM) { |
| ret = -ENOMEM; |
| goto out_unlock; |
| } else if (*flt & VM_FAULT_SIGBUS) { |
| ret = -EFAULT; |
| goto out_unlock; |
| } |
| BUG(); |
| } |
| |
| if (*flt & VM_FAULT_MAJOR) |
| current->maj_flt++; |
| else |
| current->min_flt++; |
| |
| out_unlock: |
| up_read(&mm->mmap_sem); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(spu_handle_mm_fault); |
