1 | /* |
2 | * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README |
3 | */ |
4 | |
5 | #include <linux/time.h> |
6 | #include "reiserfs.h" |
7 | #include "acl.h" |
8 | #include "xattr.h" |
9 | #include <linux/uaccess.h> |
10 | #include <linux/pagemap.h> |
11 | #include <linux/swap.h> |
12 | #include <linux/writeback.h> |
13 | #include <linux/blkdev.h> |
14 | #include <linux/buffer_head.h> |
15 | #include <linux/quotaops.h> |
16 | |
17 | /* |
18 | * We pack the tails of files on file close, not at the time they are written. |
19 | * This implies an unnecessary copy of the tail and an unnecessary indirect item |
20 | * insertion/balancing, for files that are written in one write. |
21 | * It avoids unnecessary tail packings (balances) for files that are written in |
22 | * multiple writes and are small enough to have tails. |
23 | * |
24 | * file_release is called by the VFS layer when the file is closed. If |
25 | * this is the last open file descriptor, and the file |
26 | * small enough to have a tail, and the tail is currently in an |
27 | * unformatted node, the tail is converted back into a direct item. |
28 | * |
29 | * We use reiserfs_truncate_file to pack the tail, since it already has |
30 | * all the conditions coded. |
31 | */ |
32 | static int reiserfs_file_release(struct inode *inode, struct file *filp) |
33 | { |
34 | |
35 | struct reiserfs_transaction_handle th; |
36 | int err; |
37 | int jbegin_failure = 0; |
38 | |
39 | BUG_ON(!S_ISREG(inode->i_mode)); |
40 | |
41 | if (!atomic_dec_and_mutex_lock(cnt: &REISERFS_I(inode)->openers, |
42 | lock: &REISERFS_I(inode)->tailpack)) |
43 | return 0; |
44 | |
45 | /* fast out for when nothing needs to be done */ |
46 | if ((!(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) || |
47 | !tail_has_to_be_packed(inode)) && |
48 | REISERFS_I(inode)->i_prealloc_count <= 0) { |
49 | mutex_unlock(lock: &REISERFS_I(inode)->tailpack); |
50 | return 0; |
51 | } |
52 | |
53 | reiserfs_write_lock(s: inode->i_sb); |
54 | /* |
55 | * freeing preallocation only involves relogging blocks that |
56 | * are already in the current transaction. preallocation gets |
57 | * freed at the end of each transaction, so it is impossible for |
58 | * us to log any additional blocks (including quota blocks) |
59 | */ |
60 | err = journal_begin(&th, sb: inode->i_sb, 1); |
61 | if (err) { |
62 | /* |
63 | * uh oh, we can't allow the inode to go away while there |
64 | * is still preallocation blocks pending. Try to join the |
65 | * aborted transaction |
66 | */ |
67 | jbegin_failure = err; |
68 | err = journal_join_abort(&th, sb: inode->i_sb); |
69 | |
70 | if (err) { |
71 | /* |
72 | * hmpf, our choices here aren't good. We can pin |
73 | * the inode which will disallow unmount from ever |
74 | * happening, we can do nothing, which will corrupt |
75 | * random memory on unmount, or we can forcibly |
76 | * remove the file from the preallocation list, which |
77 | * will leak blocks on disk. Lets pin the inode |
78 | * and let the admin know what is going on. |
79 | */ |
80 | igrab(inode); |
81 | reiserfs_warning(inode->i_sb, "clm-9001" , |
82 | "pinning inode %lu because the " |
83 | "preallocation can't be freed" , |
84 | inode->i_ino); |
85 | goto out; |
86 | } |
87 | } |
88 | reiserfs_update_inode_transaction(inode); |
89 | |
90 | #ifdef REISERFS_PREALLOCATE |
91 | reiserfs_discard_prealloc(th: &th, inode); |
92 | #endif |
93 | err = journal_end(&th); |
94 | |
95 | /* copy back the error code from journal_begin */ |
96 | if (!err) |
97 | err = jbegin_failure; |
98 | |
99 | if (!err && |
100 | (REISERFS_I(inode)->i_flags & i_pack_on_close_mask) && |
101 | tail_has_to_be_packed(inode)) { |
102 | |
103 | /* |
104 | * if regular file is released by last holder and it has been |
105 | * appended (we append by unformatted node only) or its direct |
106 | * item(s) had to be converted, then it may have to be |
107 | * indirect2direct converted |
108 | */ |
109 | err = reiserfs_truncate_file(inode, update_timestamps: 0); |
110 | } |
111 | out: |
112 | reiserfs_write_unlock(s: inode->i_sb); |
113 | mutex_unlock(lock: &REISERFS_I(inode)->tailpack); |
114 | return err; |
115 | } |
116 | |
117 | static int reiserfs_file_open(struct inode *inode, struct file *file) |
118 | { |
119 | int err = dquot_file_open(inode, file); |
120 | |
121 | /* somebody might be tailpacking on final close; wait for it */ |
122 | if (!atomic_inc_not_zero(v: &REISERFS_I(inode)->openers)) { |
123 | mutex_lock(&REISERFS_I(inode)->tailpack); |
124 | atomic_inc(v: &REISERFS_I(inode)->openers); |
125 | mutex_unlock(lock: &REISERFS_I(inode)->tailpack); |
126 | } |
127 | return err; |
128 | } |
129 | |
130 | void reiserfs_vfs_truncate_file(struct inode *inode) |
131 | { |
132 | mutex_lock(&REISERFS_I(inode)->tailpack); |
133 | reiserfs_truncate_file(inode, update_timestamps: 1); |
134 | mutex_unlock(lock: &REISERFS_I(inode)->tailpack); |
135 | } |
136 | |
137 | /* Sync a reiserfs file. */ |
138 | |
139 | /* |
140 | * FIXME: sync_mapping_buffers() never has anything to sync. Can |
141 | * be removed... |
142 | */ |
143 | |
144 | static int reiserfs_sync_file(struct file *filp, loff_t start, loff_t end, |
145 | int datasync) |
146 | { |
147 | struct inode *inode = filp->f_mapping->host; |
148 | int err; |
149 | int barrier_done; |
150 | |
151 | err = file_write_and_wait_range(file: filp, start, end); |
152 | if (err) |
153 | return err; |
154 | |
155 | inode_lock(inode); |
156 | BUG_ON(!S_ISREG(inode->i_mode)); |
157 | err = sync_mapping_buffers(mapping: inode->i_mapping); |
158 | reiserfs_write_lock(s: inode->i_sb); |
159 | barrier_done = reiserfs_commit_for_inode(inode); |
160 | reiserfs_write_unlock(s: inode->i_sb); |
161 | if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb)) |
162 | blkdev_issue_flush(bdev: inode->i_sb->s_bdev); |
163 | inode_unlock(inode); |
164 | if (barrier_done < 0) |
165 | return barrier_done; |
166 | return (err < 0) ? -EIO : 0; |
167 | } |
168 | |
169 | /* taken fs/buffer.c:__block_commit_write */ |
170 | int reiserfs_commit_page(struct inode *inode, struct page *page, |
171 | unsigned from, unsigned to) |
172 | { |
173 | unsigned block_start, block_end; |
174 | int partial = 0; |
175 | unsigned blocksize; |
176 | struct buffer_head *bh, *head; |
177 | unsigned long i_size_index = inode->i_size >> PAGE_SHIFT; |
178 | int new; |
179 | int logit = reiserfs_file_data_log(inode); |
180 | struct super_block *s = inode->i_sb; |
181 | int bh_per_page = PAGE_SIZE / s->s_blocksize; |
182 | struct reiserfs_transaction_handle th; |
183 | int ret = 0; |
184 | |
185 | th.t_trans_id = 0; |
186 | blocksize = i_blocksize(node: inode); |
187 | |
188 | if (logit) { |
189 | reiserfs_write_lock(s); |
190 | ret = journal_begin(&th, sb: s, bh_per_page + 1); |
191 | if (ret) |
192 | goto drop_write_lock; |
193 | reiserfs_update_inode_transaction(inode); |
194 | } |
195 | for (bh = head = page_buffers(page), block_start = 0; |
196 | bh != head || !block_start; |
197 | block_start = block_end, bh = bh->b_this_page) { |
198 | |
199 | new = buffer_new(bh); |
200 | clear_buffer_new(bh); |
201 | block_end = block_start + blocksize; |
202 | if (block_end <= from || block_start >= to) { |
203 | if (!buffer_uptodate(bh)) |
204 | partial = 1; |
205 | } else { |
206 | set_buffer_uptodate(bh); |
207 | if (logit) { |
208 | reiserfs_prepare_for_journal(s, bh, wait: 1); |
209 | journal_mark_dirty(&th, bh); |
210 | } else if (!buffer_dirty(bh)) { |
211 | mark_buffer_dirty(bh); |
212 | /* |
213 | * do data=ordered on any page past the end |
214 | * of file and any buffer marked BH_New. |
215 | */ |
216 | if (reiserfs_data_ordered(inode->i_sb) && |
217 | (new || page->index >= i_size_index)) { |
218 | reiserfs_add_ordered_list(inode, bh); |
219 | } |
220 | } |
221 | } |
222 | } |
223 | if (logit) { |
224 | ret = journal_end(&th); |
225 | drop_write_lock: |
226 | reiserfs_write_unlock(s); |
227 | } |
228 | /* |
229 | * If this is a partial write which happened to make all buffers |
230 | * uptodate then we can optimize away a bogus read_folio() for |
231 | * the next read(). Here we 'discover' whether the page went |
232 | * uptodate as a result of this (potentially partial) write. |
233 | */ |
234 | if (!partial) |
235 | SetPageUptodate(page); |
236 | return ret; |
237 | } |
238 | |
239 | const struct file_operations reiserfs_file_operations = { |
240 | .unlocked_ioctl = reiserfs_ioctl, |
241 | #ifdef CONFIG_COMPAT |
242 | .compat_ioctl = reiserfs_compat_ioctl, |
243 | #endif |
244 | .mmap = generic_file_mmap, |
245 | .open = reiserfs_file_open, |
246 | .release = reiserfs_file_release, |
247 | .fsync = reiserfs_sync_file, |
248 | .read_iter = generic_file_read_iter, |
249 | .write_iter = generic_file_write_iter, |
250 | .splice_read = filemap_splice_read, |
251 | .splice_write = iter_file_splice_write, |
252 | .llseek = generic_file_llseek, |
253 | }; |
254 | |
255 | const struct inode_operations reiserfs_file_inode_operations = { |
256 | .setattr = reiserfs_setattr, |
257 | .listxattr = reiserfs_listxattr, |
258 | .permission = reiserfs_permission, |
259 | .get_inode_acl = reiserfs_get_acl, |
260 | .set_acl = reiserfs_set_acl, |
261 | .fileattr_get = reiserfs_fileattr_get, |
262 | .fileattr_set = reiserfs_fileattr_set, |
263 | }; |
264 | |
265 | const struct inode_operations reiserfs_priv_file_inode_operations = { |
266 | .setattr = reiserfs_setattr, |
267 | .permission = reiserfs_permission, |
268 | .fileattr_get = reiserfs_fileattr_get, |
269 | .fileattr_set = reiserfs_fileattr_set, |
270 | }; |
271 | |