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