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(&REISERFS_I(inode)->openers,
42 &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(&REISERFS_I(inode)->tailpack);
50 return 0;
51 }
52
53 reiserfs_write_lock(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, 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, 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, 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, 0);
110 }
111 out:
112 reiserfs_write_unlock(inode->i_sb);
113 mutex_unlock(&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(&REISERFS_I(inode)->openers)) {
123 mutex_lock(&REISERFS_I(inode)->tailpack);
124 atomic_inc(&REISERFS_I(inode)->openers);
125 mutex_unlock(&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, 1);
134 mutex_unlock(&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(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(inode->i_mapping);
158 reiserfs_write_lock(inode->i_sb);
159 barrier_done = reiserfs_commit_for_inode(inode);
160 reiserfs_write_unlock(inode->i_sb);
161 if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb))
162 blkdev_issue_flush(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(inode);
187
188 if (logit) {
189 reiserfs_write_lock(s);
190 ret = journal_begin(&th, 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, 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
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