]> bbs.cooldavid.org Git - net-next-2.6.git/blame - fs/reiserfs/file.c
Merge branch 'fix/asoc' into for-linus
[net-next-2.6.git] / fs / reiserfs / file.c
CommitLineData
1da177e4
LT
1/*
2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3 */
4
1da177e4
LT
5#include <linux/time.h>
6#include <linux/reiserfs_fs.h>
7#include <linux/reiserfs_acl.h>
8#include <linux/reiserfs_xattr.h>
1da177e4
LT
9#include <asm/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.
0222e657 23**
1da177e4
LT
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.
0222e657 28**
1da177e4 29** We use reiserfs_truncate_file to pack the tail, since it already has
0222e657 30** all the conditions coded.
1da177e4 31*/
bd4c625c 32static int reiserfs_file_release(struct inode *inode, struct file *filp)
1da177e4
LT
33{
34
bd4c625c
LT
35 struct reiserfs_transaction_handle th;
36 int err;
37 int jbegin_failure = 0;
1da177e4 38
14a61442 39 BUG_ON(!S_ISREG(inode->i_mode));
1da177e4 40
0e4f6a79
AV
41 if (atomic_add_unless(&REISERFS_I(inode)->openers, -1, 1))
42 return 0;
43
44 mutex_lock(&(REISERFS_I(inode)->tailpack));
45
46 if (!atomic_dec_and_test(&REISERFS_I(inode)->openers)) {
47 mutex_unlock(&(REISERFS_I(inode)->tailpack));
48 return 0;
49 }
50
bd4c625c 51 /* fast out for when nothing needs to be done */
0e4f6a79 52 if ((!(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) ||
bd4c625c
LT
53 !tail_has_to_be_packed(inode)) &&
54 REISERFS_I(inode)->i_prealloc_count <= 0) {
0e4f6a79 55 mutex_unlock(&(REISERFS_I(inode)->tailpack));
bd4c625c
LT
56 return 0;
57 }
1da177e4 58
b5f3953c 59 reiserfs_write_lock(inode->i_sb);
bd4c625c
LT
60 /* freeing preallocation only involves relogging blocks that
61 * are already in the current transaction. preallocation gets
62 * freed at the end of each transaction, so it is impossible for
63 * us to log any additional blocks (including quota blocks)
64 */
65 err = journal_begin(&th, inode->i_sb, 1);
1da177e4 66 if (err) {
bd4c625c
LT
67 /* uh oh, we can't allow the inode to go away while there
68 * is still preallocation blocks pending. Try to join the
69 * aborted transaction
70 */
71 jbegin_failure = err;
72 err = journal_join_abort(&th, inode->i_sb, 1);
73
74 if (err) {
75 /* hmpf, our choices here aren't good. We can pin the inode
76 * which will disallow unmount from every happening, we can
77 * do nothing, which will corrupt random memory on unmount,
78 * or we can forcibly remove the file from the preallocation
79 * list, which will leak blocks on disk. Lets pin the inode
80 * and let the admin know what is going on.
81 */
82 igrab(inode);
45b03d5e 83 reiserfs_warning(inode->i_sb, "clm-9001",
bd4c625c 84 "pinning inode %lu because the "
533221fb
AD
85 "preallocation can't be freed",
86 inode->i_ino);
bd4c625c
LT
87 goto out;
88 }
1da177e4 89 }
bd4c625c 90 reiserfs_update_inode_transaction(inode);
1da177e4
LT
91
92#ifdef REISERFS_PREALLOCATE
bd4c625c 93 reiserfs_discard_prealloc(&th, inode);
1da177e4 94#endif
bd4c625c
LT
95 err = journal_end(&th, inode->i_sb, 1);
96
97 /* copy back the error code from journal_begin */
98 if (!err)
99 err = jbegin_failure;
100
0e4f6a79 101 if (!err &&
bd4c625c
LT
102 (REISERFS_I(inode)->i_flags & i_pack_on_close_mask) &&
103 tail_has_to_be_packed(inode)) {
0e4f6a79 104
bd4c625c
LT
105 /* if regular file is released by last holder and it has been
106 appended (we append by unformatted node only) or its direct
107 item(s) had to be converted, then it may have to be
108 indirect2direct converted */
109 err = reiserfs_truncate_file(inode, 0);
110 }
111 out:
bd4c625c 112 reiserfs_write_unlock(inode->i_sb);
0e4f6a79 113 mutex_unlock(&(REISERFS_I(inode)->tailpack));
bd4c625c 114 return err;
1da177e4
LT
115}
116
0e4f6a79 117static int reiserfs_file_open(struct inode *inode, struct file *file)
de14569f 118{
0e4f6a79
AV
119 int err = dquot_file_open(inode, file);
120 if (!atomic_inc_not_zero(&REISERFS_I(inode)->openers)) {
121 /* somebody might be tailpacking on final close; wait for it */
122 mutex_lock(&(REISERFS_I(inode)->tailpack));
123 atomic_inc(&REISERFS_I(inode)->openers);
124 mutex_unlock(&(REISERFS_I(inode)->tailpack));
125 }
126 return err;
de14569f
VS
127}
128
bd4c625c
LT
129static void reiserfs_vfs_truncate_file(struct inode *inode)
130{
0e4f6a79 131 mutex_lock(&(REISERFS_I(inode)->tailpack));
bd4c625c 132 reiserfs_truncate_file(inode, 1);
0e4f6a79 133 mutex_unlock(&(REISERFS_I(inode)->tailpack));
1da177e4
LT
134}
135
136/* Sync a reiserfs file. */
137
138/*
139 * FIXME: sync_mapping_buffers() never has anything to sync. Can
140 * be removed...
141 */
142
7ea80859 143static int reiserfs_sync_file(struct file *filp, int datasync)
bd4c625c 144{
7ea80859 145 struct inode *inode = filp->f_mapping->host;
ee93961b 146 int err;
bd4c625c
LT
147 int barrier_done;
148
995c762e 149 BUG_ON(!S_ISREG(inode->i_mode));
ee93961b 150 err = sync_mapping_buffers(inode->i_mapping);
995c762e
JM
151 reiserfs_write_lock(inode->i_sb);
152 barrier_done = reiserfs_commit_for_inode(inode);
153 reiserfs_write_unlock(inode->i_sb);
154 if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb))
dd3932ed 155 blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
bd4c625c
LT
156 if (barrier_done < 0)
157 return barrier_done;
ee93961b 158 return (err < 0) ? -EIO : 0;
1da177e4
LT
159}
160
1da177e4
LT
161/* taken fs/buffer.c:__block_commit_write */
162int reiserfs_commit_page(struct inode *inode, struct page *page,
bd4c625c 163 unsigned from, unsigned to)
1da177e4 164{
bd4c625c
LT
165 unsigned block_start, block_end;
166 int partial = 0;
167 unsigned blocksize;
168 struct buffer_head *bh, *head;
169 unsigned long i_size_index = inode->i_size >> PAGE_CACHE_SHIFT;
170 int new;
171 int logit = reiserfs_file_data_log(inode);
172 struct super_block *s = inode->i_sb;
173 int bh_per_page = PAGE_CACHE_SIZE / s->s_blocksize;
174 struct reiserfs_transaction_handle th;
175 int ret = 0;
176
177 th.t_trans_id = 0;
178 blocksize = 1 << inode->i_blkbits;
179
180 if (logit) {
181 reiserfs_write_lock(s);
182 ret = journal_begin(&th, s, bh_per_page + 1);
183 if (ret)
184 goto drop_write_lock;
185 reiserfs_update_inode_transaction(inode);
186 }
187 for (bh = head = page_buffers(page), block_start = 0;
188 bh != head || !block_start;
189 block_start = block_end, bh = bh->b_this_page) {
190
191 new = buffer_new(bh);
192 clear_buffer_new(bh);
193 block_end = block_start + blocksize;
194 if (block_end <= from || block_start >= to) {
195 if (!buffer_uptodate(bh))
196 partial = 1;
197 } else {
198 set_buffer_uptodate(bh);
199 if (logit) {
200 reiserfs_prepare_for_journal(s, bh, 1);
201 journal_mark_dirty(&th, s, bh);
202 } else if (!buffer_dirty(bh)) {
203 mark_buffer_dirty(bh);
204 /* do data=ordered on any page past the end
205 * of file and any buffer marked BH_New.
206 */
207 if (reiserfs_data_ordered(inode->i_sb) &&
208 (new || page->index >= i_size_index)) {
209 reiserfs_add_ordered_list(inode, bh);
210 }
211 }
212 }
1da177e4 213 }
bd4c625c
LT
214 if (logit) {
215 ret = journal_end(&th, s, bh_per_page + 1);
216 drop_write_lock:
217 reiserfs_write_unlock(s);
218 }
219 /*
220 * If this is a partial write which happened to make all buffers
221 * uptodate then we can optimize away a bogus readpage() for
222 * the next read(). Here we 'discover' whether the page went
223 * uptodate as a result of this (potentially partial) write.
224 */
225 if (!partial)
226 SetPageUptodate(page);
227 return ret;
1da177e4
LT
228}
229
1da177e4 230/* Write @count bytes at position @ppos in a file indicated by @file
0222e657 231 from the buffer @buf.
1da177e4
LT
232
233 generic_file_write() is only appropriate for filesystems that are not seeking to optimize performance and want
234 something simple that works. It is not for serious use by general purpose filesystems, excepting the one that it was
235 written for (ext2/3). This is for several reasons:
236
237 * It has no understanding of any filesystem specific optimizations.
238
239 * It enters the filesystem repeatedly for each page that is written.
240
241 * It depends on reiserfs_get_block() function which if implemented by reiserfs performs costly search_by_key
242 * operation for each page it is supplied with. By contrast reiserfs_file_write() feeds as much as possible at a time
243 * to reiserfs which allows for fewer tree traversals.
244
245 * Each indirect pointer insertion takes a lot of cpu, because it involves memory moves inside of blocks.
246
247 * Asking the block allocation code for blocks one at a time is slightly less efficient.
248
249 All of these reasons for not using only generic file write were understood back when reiserfs was first miscoded to
250 use it, but we were in a hurry to make code freeze, and so it couldn't be revised then. This new code should make
251 things right finally.
252
253 Future Features: providing search_by_key with hints.
254
255*/
bd4c625c
LT
256static ssize_t reiserfs_file_write(struct file *file, /* the file we are going to write into */
257 const char __user * buf, /* pointer to user supplied data
258 (in userspace) */
259 size_t count, /* amount of bytes to write */
260 loff_t * ppos /* pointer to position in file that we start writing at. Should be updated to
261 * new current position before returning. */
262 )
1da177e4 263{
1fc5adbd 264 struct inode *inode = file->f_path.dentry->d_inode; // Inode of the file that we are writing to.
bd4c625c
LT
265 /* To simplify coding at this time, we store
266 locked pages in array for now */
bd4c625c
LT
267 struct reiserfs_transaction_handle th;
268 th.t_trans_id = 0;
269
fa385bef
JM
270 /* If a filesystem is converted from 3.5 to 3.6, we'll have v3.5 items
271 * lying around (most of the disk, in fact). Despite the filesystem
272 * now being a v3.6 format, the old items still can't support large
273 * file sizes. Catch this case here, as the rest of the VFS layer is
274 * oblivious to the different limitations between old and new items.
275 * reiserfs_setattr catches this for truncates. This chunk is lifted
276 * from generic_write_checks. */
277 if (get_inode_item_key_version (inode) == KEY_FORMAT_3_5 &&
278 *ppos + count > MAX_NON_LFS) {
279 if (*ppos >= MAX_NON_LFS) {
fa385bef
JM
280 return -EFBIG;
281 }
282 if (count > MAX_NON_LFS - (unsigned long)*ppos)
283 count = MAX_NON_LFS - (unsigned long)*ppos;
284 }
285
797b4cff 286 return do_sync_write(file, buf, count, ppos);
1da177e4
LT
287}
288
4b6f5d20 289const struct file_operations reiserfs_file_operations = {
027445c3 290 .read = do_sync_read,
bd4c625c 291 .write = reiserfs_file_write,
205cb37b 292 .unlocked_ioctl = reiserfs_ioctl,
52b499c4
DH
293#ifdef CONFIG_COMPAT
294 .compat_ioctl = reiserfs_compat_ioctl,
295#endif
0e4f6a79
AV
296 .mmap = generic_file_mmap,
297 .open = reiserfs_file_open,
bd4c625c
LT
298 .release = reiserfs_file_release,
299 .fsync = reiserfs_sync_file,
bd4c625c 300 .aio_read = generic_file_aio_read,
9637f28f 301 .aio_write = generic_file_aio_write,
5274f052
JA
302 .splice_read = generic_file_splice_read,
303 .splice_write = generic_file_splice_write,
91efc167 304 .llseek = generic_file_llseek,
1da177e4
LT
305};
306
c5ef1c42 307const struct inode_operations reiserfs_file_inode_operations = {
bd4c625c
LT
308 .truncate = reiserfs_vfs_truncate_file,
309 .setattr = reiserfs_setattr,
310 .setxattr = reiserfs_setxattr,
311 .getxattr = reiserfs_getxattr,
312 .listxattr = reiserfs_listxattr,
313 .removexattr = reiserfs_removexattr,
314 .permission = reiserfs_permission,
1da177e4 315};