diff options
Diffstat (limited to 'arch/powerpc/mm')
| -rw-r--r-- | arch/powerpc/mm/Makefile | 1 | ||||
| -rw-r--r-- | arch/powerpc/mm/copro_fault.c | 92 |
2 files changed, 93 insertions, 0 deletions
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile index d0130fff20e5..325e861616a1 100644 --- a/arch/powerpc/mm/Makefile +++ b/arch/powerpc/mm/Makefile @@ -34,3 +34,4 @@ obj-$(CONFIG_TRANSPARENT_HUGEPAGE) += hugepage-hash64.o obj-$(CONFIG_PPC_SUBPAGE_PROT) += subpage-prot.o obj-$(CONFIG_NOT_COHERENT_CACHE) += dma-noncoherent.o obj-$(CONFIG_HIGHMEM) += highmem.o +obj-$(CONFIG_PPC_COPRO_BASE) += copro_fault.o diff --git a/arch/powerpc/mm/copro_fault.c b/arch/powerpc/mm/copro_fault.c new file mode 100644 index 000000000000..ba7df14c6b82 --- /dev/null +++ b/arch/powerpc/mm/copro_fault.c @@ -0,0 +1,92 @@ +/* + * CoProcessor (SPU/AFU) mm fault handler + * + * (C) Copyright IBM Deutschland Entwicklung GmbH 2007 + * + * Author: Arnd Bergmann <arndb@de.ibm.com> + * Author: Jeremy Kerr <jk@ozlabs.org> + * + * 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/export.h> +#include <asm/reg.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 copro_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 & DSISR_ISSTORE; + if (is_write) { + if (!(vma->vm_flags & VM_WRITE)) + goto out_unlock; + } else { + if (dsisr & DSISR_PROTFAULT) + 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(copro_handle_mm_fault); |