]>
Commit | Line | Data |
---|---|---|
ccd979bd MF |
1 | /* -*- mode: c; c-basic-offset: 8; -*- |
2 | * vim: noexpandtab sw=8 ts=8 sts=0: | |
3 | * | |
4 | * mmap.c | |
5 | * | |
6 | * Code to deal with the mess that is clustered mmap. | |
7 | * | |
8 | * Copyright (C) 2002, 2004 Oracle. All rights reserved. | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public | |
12 | * License as published by the Free Software Foundation; either | |
13 | * version 2 of the License, or (at your option) any later version. | |
14 | * | |
15 | * This program is distributed in the hope that it will be useful, | |
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
18 | * General Public License for more details. | |
19 | * | |
20 | * You should have received a copy of the GNU General Public | |
21 | * License along with this program; if not, write to the | |
22 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
23 | * Boston, MA 021110-1307, USA. | |
24 | */ | |
25 | ||
26 | #include <linux/fs.h> | |
27 | #include <linux/types.h> | |
ccd979bd MF |
28 | #include <linux/highmem.h> |
29 | #include <linux/pagemap.h> | |
30 | #include <linux/uio.h> | |
31 | #include <linux/signal.h> | |
32 | #include <linux/rbtree.h> | |
33 | ||
34 | #define MLOG_MASK_PREFIX ML_FILE_IO | |
35 | #include <cluster/masklog.h> | |
36 | ||
37 | #include "ocfs2.h" | |
38 | ||
7307de80 | 39 | #include "aops.h" |
ccd979bd MF |
40 | #include "dlmglue.h" |
41 | #include "file.h" | |
42 | #include "inode.h" | |
43 | #include "mmap.h" | |
e4b963f1 | 44 | #include "super.h" |
ccd979bd | 45 | |
7307de80 | 46 | |
d0217ac0 | 47 | static int ocfs2_fault(struct vm_area_struct *area, struct vm_fault *vmf) |
ccd979bd | 48 | { |
e4b963f1 JB |
49 | sigset_t oldset; |
50 | int ret; | |
ccd979bd | 51 | |
d0217ac0 | 52 | mlog_entry("(area=%p, page offset=%lu)\n", area, vmf->pgoff); |
ccd979bd | 53 | |
e4b963f1 | 54 | ocfs2_block_signals(&oldset); |
d0217ac0 | 55 | ret = filemap_fault(area, vmf); |
e4b963f1 | 56 | ocfs2_unblock_signals(&oldset); |
ccd979bd | 57 | |
d0217ac0 NP |
58 | mlog_exit_ptr(vmf->page); |
59 | return ret; | |
ccd979bd MF |
60 | } |
61 | ||
0378da0f | 62 | static int __ocfs2_page_mkwrite(struct file *file, struct buffer_head *di_bh, |
7307de80 MF |
63 | struct page *page) |
64 | { | |
65 | int ret; | |
0378da0f | 66 | struct inode *inode = file->f_path.dentry->d_inode; |
7307de80 | 67 | struct address_space *mapping = inode->i_mapping; |
18336338 | 68 | loff_t pos = page_offset(page); |
7307de80 MF |
69 | unsigned int len = PAGE_CACHE_SIZE; |
70 | pgoff_t last_index; | |
71 | struct page *locked_page = NULL; | |
72 | void *fsdata; | |
73 | loff_t size = i_size_read(inode); | |
ccd979bd | 74 | |
7307de80 MF |
75 | /* |
76 | * Another node might have truncated while we were waiting on | |
77 | * cluster locks. | |
f63afdb2 TM |
78 | * We don't check size == 0 before the shift. This is borrowed |
79 | * from do_generic_file_read. | |
7307de80 | 80 | */ |
f63afdb2 TM |
81 | last_index = (size - 1) >> PAGE_CACHE_SHIFT; |
82 | if (unlikely(!size || page->index > last_index)) { | |
7307de80 MF |
83 | ret = -EINVAL; |
84 | goto out; | |
85 | } | |
86 | ||
87 | /* | |
88 | * The i_size check above doesn't catch the case where nodes | |
89 | * truncated and then re-extended the file. We'll re-check the | |
90 | * page mapping after taking the page lock inside of | |
91 | * ocfs2_write_begin_nolock(). | |
92 | */ | |
93 | if (!PageUptodate(page) || page->mapping != inode->i_mapping) { | |
4c1bbf1b TM |
94 | /* |
95 | * the page has been umapped in ocfs2_data_downconvert_worker. | |
96 | * So return 0 here and let VFS retry. | |
97 | */ | |
98 | ret = 0; | |
7307de80 MF |
99 | goto out; |
100 | } | |
101 | ||
102 | /* | |
103 | * Call ocfs2_write_begin() and ocfs2_write_end() to take | |
104 | * advantage of the allocation code there. We pass a write | |
105 | * length of the whole page (chopped to i_size) to make sure | |
106 | * the whole thing is allocated. | |
107 | * | |
108 | * Since we know the page is up to date, we don't have to | |
109 | * worry about ocfs2_write_begin() skipping some buffer reads | |
110 | * because the "write" would invalidate their data. | |
111 | */ | |
112 | if (page->index == last_index) | |
f63afdb2 | 113 | len = ((size - 1) & ~PAGE_CACHE_MASK) + 1; |
7307de80 | 114 | |
0378da0f | 115 | ret = ocfs2_write_begin_nolock(file, mapping, pos, len, 0, &locked_page, |
7307de80 MF |
116 | &fsdata, di_bh, page); |
117 | if (ret) { | |
118 | if (ret != -ENOSPC) | |
119 | mlog_errno(ret); | |
120 | goto out; | |
121 | } | |
122 | ||
123 | ret = ocfs2_write_end_nolock(mapping, pos, len, len, locked_page, | |
124 | fsdata); | |
125 | if (ret < 0) { | |
126 | mlog_errno(ret); | |
127 | goto out; | |
128 | } | |
129 | BUG_ON(ret != len); | |
130 | ret = 0; | |
131 | out: | |
132 | return ret; | |
133 | } | |
134 | ||
c2ec175c | 135 | static int ocfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
ccd979bd | 136 | { |
c2ec175c | 137 | struct page *page = vmf->page; |
7307de80 MF |
138 | struct inode *inode = vma->vm_file->f_path.dentry->d_inode; |
139 | struct buffer_head *di_bh = NULL; | |
e4b963f1 JB |
140 | sigset_t oldset; |
141 | int ret; | |
7307de80 | 142 | |
e4b963f1 | 143 | ocfs2_block_signals(&oldset); |
7307de80 MF |
144 | |
145 | /* | |
146 | * The cluster locks taken will block a truncate from another | |
147 | * node. Taking the data lock will also ensure that we don't | |
148 | * attempt page truncation as part of a downconvert. | |
149 | */ | |
e63aecb6 | 150 | ret = ocfs2_inode_lock(inode, &di_bh, 1); |
7307de80 MF |
151 | if (ret < 0) { |
152 | mlog_errno(ret); | |
153 | goto out; | |
154 | } | |
25899dee | 155 | |
89488984 | 156 | /* |
7307de80 MF |
157 | * The alloc sem should be enough to serialize with |
158 | * ocfs2_truncate_file() changing i_size as well as any thread | |
159 | * modifying the inode btree. | |
89488984 | 160 | */ |
7307de80 MF |
161 | down_write(&OCFS2_I(inode)->ip_alloc_sem); |
162 | ||
0378da0f | 163 | ret = __ocfs2_page_mkwrite(vma->vm_file, di_bh, page); |
7307de80 | 164 | |
7307de80 MF |
165 | up_write(&OCFS2_I(inode)->ip_alloc_sem); |
166 | ||
167 | brelse(di_bh); | |
e63aecb6 | 168 | ocfs2_inode_unlock(inode, 1); |
7307de80 MF |
169 | |
170 | out: | |
e4b963f1 | 171 | ocfs2_unblock_signals(&oldset); |
c2ec175c NP |
172 | if (ret) |
173 | ret = VM_FAULT_SIGBUS; | |
7307de80 MF |
174 | return ret; |
175 | } | |
176 | ||
f0f37e2f | 177 | static const struct vm_operations_struct ocfs2_file_vm_ops = { |
54cb8821 | 178 | .fault = ocfs2_fault, |
7307de80 MF |
179 | .page_mkwrite = ocfs2_page_mkwrite, |
180 | }; | |
181 | ||
182 | int ocfs2_mmap(struct file *file, struct vm_area_struct *vma) | |
183 | { | |
184 | int ret = 0, lock_level = 0; | |
185 | ||
e63aecb6 | 186 | ret = ocfs2_inode_lock_atime(file->f_dentry->d_inode, |
25899dee TY |
187 | file->f_vfsmnt, &lock_level); |
188 | if (ret < 0) { | |
189 | mlog_errno(ret); | |
190 | goto out; | |
191 | } | |
e63aecb6 | 192 | ocfs2_inode_unlock(file->f_dentry->d_inode, lock_level); |
25899dee | 193 | out: |
ccd979bd | 194 | vma->vm_ops = &ocfs2_file_vm_ops; |
d0217ac0 | 195 | vma->vm_flags |= VM_CAN_NONLINEAR; |
ccd979bd MF |
196 | return 0; |
197 | } | |
198 |