Commit | Line | Data |
---|---|---|
7cd58e43 JK |
1 | /* |
2 | * SPU mm fault handler | |
3 | * | |
4 | * (C) Copyright IBM Deutschland Entwicklung GmbH 2007 | |
5 | * | |
6 | * Author: Arnd Bergmann <arndb@de.ibm.com> | |
7 | * Author: Jeremy Kerr <jk@ozlabs.org> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation; either version 2, or (at your option) | |
12 | * any later version. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU General Public License | |
20 | * along with this program; if not, write to the Free Software | |
21 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
22 | */ | |
23 | #include <linux/sched.h> | |
24 | #include <linux/mm.h> | |
4b16f8e2 | 25 | #include <linux/export.h> |
7cd58e43 JK |
26 | |
27 | #include <asm/spu.h> | |
28 | #include <asm/spu_csa.h> | |
29 | ||
30 | /* | |
31 | * This ought to be kept in sync with the powerpc specific do_page_fault | |
32 | * function. Currently, there are a few corner cases that we haven't had | |
33 | * to handle fortunately. | |
34 | */ | |
35 | int spu_handle_mm_fault(struct mm_struct *mm, unsigned long ea, | |
36 | unsigned long dsisr, unsigned *flt) | |
37 | { | |
38 | struct vm_area_struct *vma; | |
39 | unsigned long is_write; | |
40 | int ret; | |
41 | ||
60ee0319 | 42 | if (mm == NULL) |
7cd58e43 | 43 | return -EFAULT; |
60ee0319 JK |
44 | |
45 | if (mm->pgd == NULL) | |
7cd58e43 | 46 | return -EFAULT; |
7cd58e43 JK |
47 | |
48 | down_read(&mm->mmap_sem); | |
60ee0319 | 49 | ret = -EFAULT; |
7cd58e43 JK |
50 | vma = find_vma(mm, ea); |
51 | if (!vma) | |
60ee0319 JK |
52 | goto out_unlock; |
53 | ||
54 | if (ea < vma->vm_start) { | |
55 | if (!(vma->vm_flags & VM_GROWSDOWN)) | |
56 | goto out_unlock; | |
57 | if (expand_stack(vma, ea)) | |
58 | goto out_unlock; | |
59 | } | |
60 | ||
7cd58e43 JK |
61 | is_write = dsisr & MFC_DSISR_ACCESS_PUT; |
62 | if (is_write) { | |
63 | if (!(vma->vm_flags & VM_WRITE)) | |
60ee0319 | 64 | goto out_unlock; |
7cd58e43 JK |
65 | } else { |
66 | if (dsisr & MFC_DSISR_ACCESS_DENIED) | |
60ee0319 | 67 | goto out_unlock; |
7cd58e43 | 68 | if (!(vma->vm_flags & (VM_READ | VM_EXEC))) |
60ee0319 | 69 | goto out_unlock; |
7cd58e43 | 70 | } |
60ee0319 | 71 | |
7cd58e43 | 72 | ret = 0; |
d06063cc | 73 | *flt = handle_mm_fault(mm, vma, ea, is_write ? FAULT_FLAG_WRITE : 0); |
7cd58e43 JK |
74 | if (unlikely(*flt & VM_FAULT_ERROR)) { |
75 | if (*flt & VM_FAULT_OOM) { | |
76 | ret = -ENOMEM; | |
60ee0319 | 77 | goto out_unlock; |
7cd58e43 JK |
78 | } else if (*flt & VM_FAULT_SIGBUS) { |
79 | ret = -EFAULT; | |
60ee0319 | 80 | goto out_unlock; |
7cd58e43 JK |
81 | } |
82 | BUG(); | |
83 | } | |
60ee0319 | 84 | |
7cd58e43 JK |
85 | if (*flt & VM_FAULT_MAJOR) |
86 | current->maj_flt++; | |
87 | else | |
88 | current->min_flt++; | |
7cd58e43 | 89 | |
60ee0319 | 90 | out_unlock: |
7cd58e43 | 91 | up_read(&mm->mmap_sem); |
60ee0319 | 92 | return ret; |
7cd58e43 JK |
93 | } |
94 | EXPORT_SYMBOL_GPL(spu_handle_mm_fault); |