xref: /linux/fs/ocfs2/quota_global.c (revision 765532c8aaac624b5f8687af6d319c6a1138a257)
1 /*
2  *  Implementation of operations over global quota file
3  */
4 #include <linux/spinlock.h>
5 #include <linux/fs.h>
6 #include <linux/slab.h>
7 #include <linux/quota.h>
8 #include <linux/quotaops.h>
9 #include <linux/dqblk_qtree.h>
10 #include <linux/jiffies.h>
11 #include <linux/writeback.h>
12 #include <linux/workqueue.h>
13 
14 #define MLOG_MASK_PREFIX ML_QUOTA
15 #include <cluster/masklog.h>
16 
17 #include "ocfs2_fs.h"
18 #include "ocfs2.h"
19 #include "alloc.h"
20 #include "blockcheck.h"
21 #include "inode.h"
22 #include "journal.h"
23 #include "file.h"
24 #include "sysfile.h"
25 #include "dlmglue.h"
26 #include "uptodate.h"
27 #include "super.h"
28 #include "buffer_head_io.h"
29 #include "quota.h"
30 
31 /*
32  * Locking of quotas with OCFS2 is rather complex. Here are rules that
33  * should be obeyed by all the functions:
34  * - any write of quota structure (either to local or global file) is protected
35  *   by dqio_mutex or dquot->dq_lock.
36  * - any modification of global quota file holds inode cluster lock, i_mutex,
37  *   and ip_alloc_sem of the global quota file (achieved by
38  *   ocfs2_lock_global_qf). It also has to hold qinfo_lock.
39  * - an allocation of new blocks for local quota file is protected by
40  *   its ip_alloc_sem
41  *
42  * A rough sketch of locking dependencies (lf = local file, gf = global file):
43  * Normal filesystem operation:
44  *   start_trans -> dqio_mutex -> write to lf
45  * Syncing of local and global file:
46  *   ocfs2_lock_global_qf -> start_trans -> dqio_mutex -> qinfo_lock ->
47  *     write to gf
48  *						       -> write to lf
49  * Acquire dquot for the first time:
50  *   dq_lock -> ocfs2_lock_global_qf -> qinfo_lock -> read from gf
51  *				     -> alloc space for gf
52  *				     -> start_trans -> qinfo_lock -> write to gf
53  *	     -> ip_alloc_sem of lf -> alloc space for lf
54  *	     -> write to lf
55  * Release last reference to dquot:
56  *   dq_lock -> ocfs2_lock_global_qf -> start_trans -> qinfo_lock -> write to gf
57  *	     -> write to lf
58  * Note that all the above operations also hold the inode cluster lock of lf.
59  * Recovery:
60  *   inode cluster lock of recovered lf
61  *     -> read bitmaps -> ip_alloc_sem of lf
62  *     -> ocfs2_lock_global_qf -> start_trans -> dqio_mutex -> qinfo_lock ->
63  *        write to gf
64  */
65 
66 static struct workqueue_struct *ocfs2_quota_wq = NULL;
67 
68 static void qsync_work_fn(struct work_struct *work);
69 
70 static void ocfs2_global_disk2memdqb(struct dquot *dquot, void *dp)
71 {
72 	struct ocfs2_global_disk_dqblk *d = dp;
73 	struct mem_dqblk *m = &dquot->dq_dqb;
74 
75 	/* Update from disk only entries not set by the admin */
76 	if (!test_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags)) {
77 		m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
78 		m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
79 	}
80 	if (!test_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags))
81 		m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
82 	if (!test_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags)) {
83 		m->dqb_bhardlimit = le64_to_cpu(d->dqb_bhardlimit);
84 		m->dqb_bsoftlimit = le64_to_cpu(d->dqb_bsoftlimit);
85 	}
86 	if (!test_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags))
87 		m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
88 	if (!test_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags))
89 		m->dqb_btime = le64_to_cpu(d->dqb_btime);
90 	if (!test_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags))
91 		m->dqb_itime = le64_to_cpu(d->dqb_itime);
92 	OCFS2_DQUOT(dquot)->dq_use_count = le32_to_cpu(d->dqb_use_count);
93 }
94 
95 static void ocfs2_global_mem2diskdqb(void *dp, struct dquot *dquot)
96 {
97 	struct ocfs2_global_disk_dqblk *d = dp;
98 	struct mem_dqblk *m = &dquot->dq_dqb;
99 
100 	d->dqb_id = cpu_to_le32(dquot->dq_id);
101 	d->dqb_use_count = cpu_to_le32(OCFS2_DQUOT(dquot)->dq_use_count);
102 	d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
103 	d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
104 	d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
105 	d->dqb_bhardlimit = cpu_to_le64(m->dqb_bhardlimit);
106 	d->dqb_bsoftlimit = cpu_to_le64(m->dqb_bsoftlimit);
107 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
108 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
109 	d->dqb_itime = cpu_to_le64(m->dqb_itime);
110 	d->dqb_pad1 = d->dqb_pad2 = 0;
111 }
112 
113 static int ocfs2_global_is_id(void *dp, struct dquot *dquot)
114 {
115 	struct ocfs2_global_disk_dqblk *d = dp;
116 	struct ocfs2_mem_dqinfo *oinfo =
117 			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
118 
119 	if (qtree_entry_unused(&oinfo->dqi_gi, dp))
120 		return 0;
121 	return le32_to_cpu(d->dqb_id) == dquot->dq_id;
122 }
123 
124 struct qtree_fmt_operations ocfs2_global_ops = {
125 	.mem2disk_dqblk = ocfs2_global_mem2diskdqb,
126 	.disk2mem_dqblk = ocfs2_global_disk2memdqb,
127 	.is_id = ocfs2_global_is_id,
128 };
129 
130 int ocfs2_validate_quota_block(struct super_block *sb, struct buffer_head *bh)
131 {
132 	struct ocfs2_disk_dqtrailer *dqt =
133 		ocfs2_block_dqtrailer(sb->s_blocksize, bh->b_data);
134 
135 	mlog(0, "Validating quota block %llu\n",
136 	     (unsigned long long)bh->b_blocknr);
137 
138 	BUG_ON(!buffer_uptodate(bh));
139 
140 	/*
141 	 * If the ecc fails, we return the error but otherwise
142 	 * leave the filesystem running.  We know any error is
143 	 * local to this block.
144 	 */
145 	return ocfs2_validate_meta_ecc(sb, bh->b_data, &dqt->dq_check);
146 }
147 
148 int ocfs2_read_quota_phys_block(struct inode *inode, u64 p_block,
149 				struct buffer_head **bhp)
150 {
151 	int rc;
152 
153 	*bhp = NULL;
154 	rc = ocfs2_read_blocks(INODE_CACHE(inode), p_block, 1, bhp, 0,
155 			       ocfs2_validate_quota_block);
156 	if (rc)
157 		mlog_errno(rc);
158 	return rc;
159 }
160 
161 /* Read data from global quotafile - avoid pagecache and such because we cannot
162  * afford acquiring the locks... We use quota cluster lock to serialize
163  * operations. Caller is responsible for acquiring it. */
164 ssize_t ocfs2_quota_read(struct super_block *sb, int type, char *data,
165 			 size_t len, loff_t off)
166 {
167 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
168 	struct inode *gqinode = oinfo->dqi_gqinode;
169 	loff_t i_size = i_size_read(gqinode);
170 	int offset = off & (sb->s_blocksize - 1);
171 	sector_t blk = off >> sb->s_blocksize_bits;
172 	int err = 0;
173 	struct buffer_head *bh;
174 	size_t toread, tocopy;
175 	u64 pblock = 0, pcount = 0;
176 
177 	if (off > i_size)
178 		return 0;
179 	if (off + len > i_size)
180 		len = i_size - off;
181 	toread = len;
182 	while (toread > 0) {
183 		tocopy = min_t(size_t, (sb->s_blocksize - offset), toread);
184 		if (!pcount) {
185 			err = ocfs2_extent_map_get_blocks(gqinode, blk, &pblock,
186 							  &pcount, NULL);
187 			if (err) {
188 				mlog_errno(err);
189 				return err;
190 			}
191 		} else {
192 			pcount--;
193 			pblock++;
194 		}
195 		bh = NULL;
196 		err = ocfs2_read_quota_phys_block(gqinode, pblock, &bh);
197 		if (err) {
198 			mlog_errno(err);
199 			return err;
200 		}
201 		memcpy(data, bh->b_data + offset, tocopy);
202 		brelse(bh);
203 		offset = 0;
204 		toread -= tocopy;
205 		data += tocopy;
206 		blk++;
207 	}
208 	return len;
209 }
210 
211 /* Write to quotafile (we know the transaction is already started and has
212  * enough credits) */
213 ssize_t ocfs2_quota_write(struct super_block *sb, int type,
214 			  const char *data, size_t len, loff_t off)
215 {
216 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
217 	struct ocfs2_mem_dqinfo *oinfo = info->dqi_priv;
218 	struct inode *gqinode = oinfo->dqi_gqinode;
219 	int offset = off & (sb->s_blocksize - 1);
220 	sector_t blk = off >> sb->s_blocksize_bits;
221 	int err = 0, new = 0, ja_type;
222 	struct buffer_head *bh = NULL;
223 	handle_t *handle = journal_current_handle();
224 	u64 pblock, pcount;
225 
226 	if (!handle) {
227 		mlog(ML_ERROR, "Quota write (off=%llu, len=%llu) cancelled "
228 		     "because transaction was not started.\n",
229 		     (unsigned long long)off, (unsigned long long)len);
230 		return -EIO;
231 	}
232 	if (len > sb->s_blocksize - OCFS2_QBLK_RESERVED_SPACE - offset) {
233 		WARN_ON(1);
234 		len = sb->s_blocksize - OCFS2_QBLK_RESERVED_SPACE - offset;
235 	}
236 
237 	if (gqinode->i_size < off + len) {
238 		loff_t rounded_end =
239 				ocfs2_align_bytes_to_blocks(sb, off + len);
240 
241 		/* Space is already allocated in ocfs2_acquire_dquot() */
242 		err = ocfs2_simple_size_update(gqinode,
243 					       oinfo->dqi_gqi_bh,
244 					       rounded_end);
245 		if (err < 0)
246 			goto out;
247 		new = 1;
248 	}
249 	err = ocfs2_extent_map_get_blocks(gqinode, blk, &pblock, &pcount, NULL);
250 	if (err) {
251 		mlog_errno(err);
252 		goto out;
253 	}
254 	/* Not rewriting whole block? */
255 	if ((offset || len < sb->s_blocksize - OCFS2_QBLK_RESERVED_SPACE) &&
256 	    !new) {
257 		err = ocfs2_read_quota_phys_block(gqinode, pblock, &bh);
258 		ja_type = OCFS2_JOURNAL_ACCESS_WRITE;
259 	} else {
260 		bh = sb_getblk(sb, pblock);
261 		if (!bh)
262 			err = -ENOMEM;
263 		ja_type = OCFS2_JOURNAL_ACCESS_CREATE;
264 	}
265 	if (err) {
266 		mlog_errno(err);
267 		goto out;
268 	}
269 	lock_buffer(bh);
270 	if (new)
271 		memset(bh->b_data, 0, sb->s_blocksize);
272 	memcpy(bh->b_data + offset, data, len);
273 	flush_dcache_page(bh->b_page);
274 	set_buffer_uptodate(bh);
275 	unlock_buffer(bh);
276 	ocfs2_set_buffer_uptodate(INODE_CACHE(gqinode), bh);
277 	err = ocfs2_journal_access_dq(handle, INODE_CACHE(gqinode), bh,
278 				      ja_type);
279 	if (err < 0) {
280 		brelse(bh);
281 		goto out;
282 	}
283 	ocfs2_journal_dirty(handle, bh);
284 	brelse(bh);
285 out:
286 	if (err) {
287 		mlog_errno(err);
288 		return err;
289 	}
290 	gqinode->i_version++;
291 	ocfs2_mark_inode_dirty(handle, gqinode, oinfo->dqi_gqi_bh);
292 	return len;
293 }
294 
295 int ocfs2_lock_global_qf(struct ocfs2_mem_dqinfo *oinfo, int ex)
296 {
297 	int status;
298 	struct buffer_head *bh = NULL;
299 
300 	status = ocfs2_inode_lock(oinfo->dqi_gqinode, &bh, ex);
301 	if (status < 0)
302 		return status;
303 	spin_lock(&dq_data_lock);
304 	if (!oinfo->dqi_gqi_count++)
305 		oinfo->dqi_gqi_bh = bh;
306 	else
307 		WARN_ON(bh != oinfo->dqi_gqi_bh);
308 	spin_unlock(&dq_data_lock);
309 	if (ex) {
310 		mutex_lock(&oinfo->dqi_gqinode->i_mutex);
311 		down_write(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
312 	} else {
313 		down_read(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
314 	}
315 	return 0;
316 }
317 
318 void ocfs2_unlock_global_qf(struct ocfs2_mem_dqinfo *oinfo, int ex)
319 {
320 	if (ex) {
321 		up_write(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
322 		mutex_unlock(&oinfo->dqi_gqinode->i_mutex);
323 	} else {
324 		up_read(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
325 	}
326 	ocfs2_inode_unlock(oinfo->dqi_gqinode, ex);
327 	brelse(oinfo->dqi_gqi_bh);
328 	spin_lock(&dq_data_lock);
329 	if (!--oinfo->dqi_gqi_count)
330 		oinfo->dqi_gqi_bh = NULL;
331 	spin_unlock(&dq_data_lock);
332 }
333 
334 /* Read information header from global quota file */
335 int ocfs2_global_read_info(struct super_block *sb, int type)
336 {
337 	struct inode *gqinode = NULL;
338 	unsigned int ino[MAXQUOTAS] = { USER_QUOTA_SYSTEM_INODE,
339 					GROUP_QUOTA_SYSTEM_INODE };
340 	struct ocfs2_global_disk_dqinfo dinfo;
341 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
342 	struct ocfs2_mem_dqinfo *oinfo = info->dqi_priv;
343 	u64 pcount;
344 	int status;
345 
346 	mlog_entry_void();
347 
348 	/* Read global header */
349 	gqinode = ocfs2_get_system_file_inode(OCFS2_SB(sb), ino[type],
350 			OCFS2_INVALID_SLOT);
351 	if (!gqinode) {
352 		mlog(ML_ERROR, "failed to get global quota inode (type=%d)\n",
353 			type);
354 		status = -EINVAL;
355 		goto out_err;
356 	}
357 	oinfo->dqi_gi.dqi_sb = sb;
358 	oinfo->dqi_gi.dqi_type = type;
359 	ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo);
360 	oinfo->dqi_gi.dqi_entry_size = sizeof(struct ocfs2_global_disk_dqblk);
361 	oinfo->dqi_gi.dqi_ops = &ocfs2_global_ops;
362 	oinfo->dqi_gqi_bh = NULL;
363 	oinfo->dqi_gqi_count = 0;
364 	oinfo->dqi_gqinode = gqinode;
365 	status = ocfs2_lock_global_qf(oinfo, 0);
366 	if (status < 0) {
367 		mlog_errno(status);
368 		goto out_err;
369 	}
370 
371 	status = ocfs2_extent_map_get_blocks(gqinode, 0, &oinfo->dqi_giblk,
372 					     &pcount, NULL);
373 	if (status < 0)
374 		goto out_unlock;
375 
376 	status = ocfs2_qinfo_lock(oinfo, 0);
377 	if (status < 0)
378 		goto out_unlock;
379 	status = sb->s_op->quota_read(sb, type, (char *)&dinfo,
380 				      sizeof(struct ocfs2_global_disk_dqinfo),
381 				      OCFS2_GLOBAL_INFO_OFF);
382 	ocfs2_qinfo_unlock(oinfo, 0);
383 	ocfs2_unlock_global_qf(oinfo, 0);
384 	if (status != sizeof(struct ocfs2_global_disk_dqinfo)) {
385 		mlog(ML_ERROR, "Cannot read global quota info (%d).\n",
386 		     status);
387 		if (status >= 0)
388 			status = -EIO;
389 		mlog_errno(status);
390 		goto out_err;
391 	}
392 	info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
393 	info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
394 	oinfo->dqi_syncms = le32_to_cpu(dinfo.dqi_syncms);
395 	oinfo->dqi_gi.dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
396 	oinfo->dqi_gi.dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
397 	oinfo->dqi_gi.dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
398 	oinfo->dqi_gi.dqi_blocksize_bits = sb->s_blocksize_bits;
399 	oinfo->dqi_gi.dqi_usable_bs = sb->s_blocksize -
400 						OCFS2_QBLK_RESERVED_SPACE;
401 	oinfo->dqi_gi.dqi_qtree_depth = qtree_depth(&oinfo->dqi_gi);
402 	INIT_DELAYED_WORK(&oinfo->dqi_sync_work, qsync_work_fn);
403 	queue_delayed_work(ocfs2_quota_wq, &oinfo->dqi_sync_work,
404 			   msecs_to_jiffies(oinfo->dqi_syncms));
405 
406 out_err:
407 	mlog_exit(status);
408 	return status;
409 out_unlock:
410 	ocfs2_unlock_global_qf(oinfo, 0);
411 	mlog_errno(status);
412 	goto out_err;
413 }
414 
415 /* Write information to global quota file. Expects exlusive lock on quota
416  * file inode and quota info */
417 static int __ocfs2_global_write_info(struct super_block *sb, int type)
418 {
419 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
420 	struct ocfs2_mem_dqinfo *oinfo = info->dqi_priv;
421 	struct ocfs2_global_disk_dqinfo dinfo;
422 	ssize_t size;
423 
424 	spin_lock(&dq_data_lock);
425 	info->dqi_flags &= ~DQF_INFO_DIRTY;
426 	dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
427 	dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
428 	spin_unlock(&dq_data_lock);
429 	dinfo.dqi_syncms = cpu_to_le32(oinfo->dqi_syncms);
430 	dinfo.dqi_blocks = cpu_to_le32(oinfo->dqi_gi.dqi_blocks);
431 	dinfo.dqi_free_blk = cpu_to_le32(oinfo->dqi_gi.dqi_free_blk);
432 	dinfo.dqi_free_entry = cpu_to_le32(oinfo->dqi_gi.dqi_free_entry);
433 	size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
434 				     sizeof(struct ocfs2_global_disk_dqinfo),
435 				     OCFS2_GLOBAL_INFO_OFF);
436 	if (size != sizeof(struct ocfs2_global_disk_dqinfo)) {
437 		mlog(ML_ERROR, "Cannot write global quota info structure\n");
438 		if (size >= 0)
439 			size = -EIO;
440 		return size;
441 	}
442 	return 0;
443 }
444 
445 int ocfs2_global_write_info(struct super_block *sb, int type)
446 {
447 	int err;
448 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
449 
450 	err = ocfs2_qinfo_lock(info, 1);
451 	if (err < 0)
452 		return err;
453 	err = __ocfs2_global_write_info(sb, type);
454 	ocfs2_qinfo_unlock(info, 1);
455 	return err;
456 }
457 
458 static int ocfs2_global_qinit_alloc(struct super_block *sb, int type)
459 {
460 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
461 
462 	/*
463 	 * We may need to allocate tree blocks and a leaf block but not the
464 	 * root block
465 	 */
466 	return oinfo->dqi_gi.dqi_qtree_depth;
467 }
468 
469 static int ocfs2_calc_global_qinit_credits(struct super_block *sb, int type)
470 {
471 	/* We modify all the allocated blocks, tree root, info block and
472 	 * the inode */
473 	return (ocfs2_global_qinit_alloc(sb, type) + 2) *
474 			OCFS2_QUOTA_BLOCK_UPDATE_CREDITS + 1;
475 }
476 
477 /* Sync local information about quota modifications with global quota file.
478  * Caller must have started the transaction and obtained exclusive lock for
479  * global quota file inode */
480 int __ocfs2_sync_dquot(struct dquot *dquot, int freeing)
481 {
482 	int err, err2;
483 	struct super_block *sb = dquot->dq_sb;
484 	int type = dquot->dq_type;
485 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
486 	struct ocfs2_global_disk_dqblk dqblk;
487 	s64 spacechange, inodechange;
488 	time_t olditime, oldbtime;
489 
490 	err = sb->s_op->quota_read(sb, type, (char *)&dqblk,
491 				   sizeof(struct ocfs2_global_disk_dqblk),
492 				   dquot->dq_off);
493 	if (err != sizeof(struct ocfs2_global_disk_dqblk)) {
494 		if (err >= 0) {
495 			mlog(ML_ERROR, "Short read from global quota file "
496 				       "(%u read)\n", err);
497 			err = -EIO;
498 		}
499 		goto out;
500 	}
501 
502 	/* Update space and inode usage. Get also other information from
503 	 * global quota file so that we don't overwrite any changes there.
504 	 * We are */
505 	spin_lock(&dq_data_lock);
506 	spacechange = dquot->dq_dqb.dqb_curspace -
507 					OCFS2_DQUOT(dquot)->dq_origspace;
508 	inodechange = dquot->dq_dqb.dqb_curinodes -
509 					OCFS2_DQUOT(dquot)->dq_originodes;
510 	olditime = dquot->dq_dqb.dqb_itime;
511 	oldbtime = dquot->dq_dqb.dqb_btime;
512 	ocfs2_global_disk2memdqb(dquot, &dqblk);
513 	mlog(0, "Syncing global dquot %u space %lld+%lld, inodes %lld+%lld\n",
514 	     dquot->dq_id, dquot->dq_dqb.dqb_curspace, (long long)spacechange,
515 	     dquot->dq_dqb.dqb_curinodes, (long long)inodechange);
516 	if (!test_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags))
517 		dquot->dq_dqb.dqb_curspace += spacechange;
518 	if (!test_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags))
519 		dquot->dq_dqb.dqb_curinodes += inodechange;
520 	/* Set properly space grace time... */
521 	if (dquot->dq_dqb.dqb_bsoftlimit &&
522 	    dquot->dq_dqb.dqb_curspace > dquot->dq_dqb.dqb_bsoftlimit) {
523 		if (!test_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags) &&
524 		    oldbtime > 0) {
525 			if (dquot->dq_dqb.dqb_btime > 0)
526 				dquot->dq_dqb.dqb_btime =
527 					min(dquot->dq_dqb.dqb_btime, oldbtime);
528 			else
529 				dquot->dq_dqb.dqb_btime = oldbtime;
530 		}
531 	} else {
532 		dquot->dq_dqb.dqb_btime = 0;
533 		clear_bit(DQ_BLKS_B, &dquot->dq_flags);
534 	}
535 	/* Set properly inode grace time... */
536 	if (dquot->dq_dqb.dqb_isoftlimit &&
537 	    dquot->dq_dqb.dqb_curinodes > dquot->dq_dqb.dqb_isoftlimit) {
538 		if (!test_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags) &&
539 		    olditime > 0) {
540 			if (dquot->dq_dqb.dqb_itime > 0)
541 				dquot->dq_dqb.dqb_itime =
542 					min(dquot->dq_dqb.dqb_itime, olditime);
543 			else
544 				dquot->dq_dqb.dqb_itime = olditime;
545 		}
546 	} else {
547 		dquot->dq_dqb.dqb_itime = 0;
548 		clear_bit(DQ_INODES_B, &dquot->dq_flags);
549 	}
550 	/* All information is properly updated, clear the flags */
551 	__clear_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
552 	__clear_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
553 	__clear_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
554 	__clear_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
555 	__clear_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
556 	__clear_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
557 	OCFS2_DQUOT(dquot)->dq_origspace = dquot->dq_dqb.dqb_curspace;
558 	OCFS2_DQUOT(dquot)->dq_originodes = dquot->dq_dqb.dqb_curinodes;
559 	spin_unlock(&dq_data_lock);
560 	err = ocfs2_qinfo_lock(info, freeing);
561 	if (err < 0) {
562 		mlog(ML_ERROR, "Failed to lock quota info, loosing quota write"
563 			       " (type=%d, id=%u)\n", dquot->dq_type,
564 			       (unsigned)dquot->dq_id);
565 		goto out;
566 	}
567 	if (freeing)
568 		OCFS2_DQUOT(dquot)->dq_use_count--;
569 	err = qtree_write_dquot(&info->dqi_gi, dquot);
570 	if (err < 0)
571 		goto out_qlock;
572 	if (freeing && !OCFS2_DQUOT(dquot)->dq_use_count) {
573 		err = qtree_release_dquot(&info->dqi_gi, dquot);
574 		if (info_dirty(sb_dqinfo(sb, type))) {
575 			err2 = __ocfs2_global_write_info(sb, type);
576 			if (!err)
577 				err = err2;
578 		}
579 	}
580 out_qlock:
581 	ocfs2_qinfo_unlock(info, freeing);
582 out:
583 	if (err < 0)
584 		mlog_errno(err);
585 	return err;
586 }
587 
588 /*
589  *  Functions for periodic syncing of dquots with global file
590  */
591 static int ocfs2_sync_dquot_helper(struct dquot *dquot, unsigned long type)
592 {
593 	handle_t *handle;
594 	struct super_block *sb = dquot->dq_sb;
595 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
596 	struct ocfs2_super *osb = OCFS2_SB(sb);
597 	int status = 0;
598 
599 	mlog_entry("id=%u qtype=%u type=%lu device=%s\n", dquot->dq_id,
600 		   dquot->dq_type, type, sb->s_id);
601 	if (type != dquot->dq_type)
602 		goto out;
603 	status = ocfs2_lock_global_qf(oinfo, 1);
604 	if (status < 0)
605 		goto out;
606 
607 	handle = ocfs2_start_trans(osb, OCFS2_QSYNC_CREDITS);
608 	if (IS_ERR(handle)) {
609 		status = PTR_ERR(handle);
610 		mlog_errno(status);
611 		goto out_ilock;
612 	}
613 	mutex_lock(&sb_dqopt(sb)->dqio_mutex);
614 	status = ocfs2_sync_dquot(dquot);
615 	if (status < 0)
616 		mlog_errno(status);
617 	/* We have to write local structure as well... */
618 	status = ocfs2_local_write_dquot(dquot);
619 	if (status < 0)
620 		mlog_errno(status);
621 	mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
622 	ocfs2_commit_trans(osb, handle);
623 out_ilock:
624 	ocfs2_unlock_global_qf(oinfo, 1);
625 out:
626 	mlog_exit(status);
627 	return status;
628 }
629 
630 static void qsync_work_fn(struct work_struct *work)
631 {
632 	struct ocfs2_mem_dqinfo *oinfo = container_of(work,
633 						      struct ocfs2_mem_dqinfo,
634 						      dqi_sync_work.work);
635 	struct super_block *sb = oinfo->dqi_gqinode->i_sb;
636 
637 	dquot_scan_active(sb, ocfs2_sync_dquot_helper, oinfo->dqi_type);
638 	queue_delayed_work(ocfs2_quota_wq, &oinfo->dqi_sync_work,
639 			   msecs_to_jiffies(oinfo->dqi_syncms));
640 }
641 
642 /*
643  *  Wrappers for generic quota functions
644  */
645 
646 static int ocfs2_write_dquot(struct dquot *dquot)
647 {
648 	handle_t *handle;
649 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
650 	int status = 0;
651 
652 	mlog_entry("id=%u, type=%d", dquot->dq_id, dquot->dq_type);
653 
654 	handle = ocfs2_start_trans(osb, OCFS2_QWRITE_CREDITS);
655 	if (IS_ERR(handle)) {
656 		status = PTR_ERR(handle);
657 		mlog_errno(status);
658 		goto out;
659 	}
660 	mutex_lock(&sb_dqopt(dquot->dq_sb)->dqio_mutex);
661 	status = ocfs2_local_write_dquot(dquot);
662 	mutex_unlock(&sb_dqopt(dquot->dq_sb)->dqio_mutex);
663 	ocfs2_commit_trans(osb, handle);
664 out:
665 	mlog_exit(status);
666 	return status;
667 }
668 
669 static int ocfs2_calc_qdel_credits(struct super_block *sb, int type)
670 {
671 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
672 	/*
673 	 * We modify tree, leaf block, global info, local chunk header,
674 	 * global and local inode; OCFS2_QINFO_WRITE_CREDITS already
675 	 * accounts for inode update
676 	 */
677 	return (oinfo->dqi_gi.dqi_qtree_depth + 2) *
678 	       OCFS2_QUOTA_BLOCK_UPDATE_CREDITS +
679 	       OCFS2_QINFO_WRITE_CREDITS +
680 	       OCFS2_INODE_UPDATE_CREDITS;
681 }
682 
683 static int ocfs2_release_dquot(struct dquot *dquot)
684 {
685 	handle_t *handle;
686 	struct ocfs2_mem_dqinfo *oinfo =
687 			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
688 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
689 	int status = 0;
690 
691 	mlog_entry("id=%u, type=%d", dquot->dq_id, dquot->dq_type);
692 
693 	mutex_lock(&dquot->dq_lock);
694 	/* Check whether we are not racing with some other dqget() */
695 	if (atomic_read(&dquot->dq_count) > 1)
696 		goto out;
697 	status = ocfs2_lock_global_qf(oinfo, 1);
698 	if (status < 0)
699 		goto out;
700 	handle = ocfs2_start_trans(osb,
701 		ocfs2_calc_qdel_credits(dquot->dq_sb, dquot->dq_type));
702 	if (IS_ERR(handle)) {
703 		status = PTR_ERR(handle);
704 		mlog_errno(status);
705 		goto out_ilock;
706 	}
707 
708 	status = ocfs2_global_release_dquot(dquot);
709 	if (status < 0) {
710 		mlog_errno(status);
711 		goto out_trans;
712 	}
713 	status = ocfs2_local_release_dquot(handle, dquot);
714 	/*
715 	 * If we fail here, we cannot do much as global structure is
716 	 * already released. So just complain...
717 	 */
718 	if (status < 0)
719 		mlog_errno(status);
720 	clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
721 out_trans:
722 	ocfs2_commit_trans(osb, handle);
723 out_ilock:
724 	ocfs2_unlock_global_qf(oinfo, 1);
725 out:
726 	mutex_unlock(&dquot->dq_lock);
727 	mlog_exit(status);
728 	return status;
729 }
730 
731 /*
732  * Read global dquot structure from disk or create it if it does
733  * not exist. Also update use count of the global structure and
734  * create structure in node-local quota file.
735  */
736 static int ocfs2_acquire_dquot(struct dquot *dquot)
737 {
738 	int status = 0, err;
739 	int ex = 0;
740 	struct super_block *sb = dquot->dq_sb;
741 	struct ocfs2_super *osb = OCFS2_SB(sb);
742 	int type = dquot->dq_type;
743 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
744 	struct inode *gqinode = info->dqi_gqinode;
745 	int need_alloc = ocfs2_global_qinit_alloc(sb, type);
746 	handle_t *handle;
747 
748 	mlog_entry("id=%u, type=%d", dquot->dq_id, type);
749 	mutex_lock(&dquot->dq_lock);
750 	/*
751 	 * We need an exclusive lock, because we're going to update use count
752 	 * and instantiate possibly new dquot structure
753 	 */
754 	status = ocfs2_lock_global_qf(info, 1);
755 	if (status < 0)
756 		goto out;
757 	if (!test_bit(DQ_READ_B, &dquot->dq_flags)) {
758 		status = ocfs2_qinfo_lock(info, 0);
759 		if (status < 0)
760 			goto out_dq;
761 		status = qtree_read_dquot(&info->dqi_gi, dquot);
762 		ocfs2_qinfo_unlock(info, 0);
763 		if (status < 0)
764 			goto out_dq;
765 	}
766 	set_bit(DQ_READ_B, &dquot->dq_flags);
767 
768 	OCFS2_DQUOT(dquot)->dq_use_count++;
769 	OCFS2_DQUOT(dquot)->dq_origspace = dquot->dq_dqb.dqb_curspace;
770 	OCFS2_DQUOT(dquot)->dq_originodes = dquot->dq_dqb.dqb_curinodes;
771 	if (!dquot->dq_off) {	/* No real quota entry? */
772 		ex = 1;
773 		/*
774 		 * Add blocks to quota file before we start a transaction since
775 		 * locking allocators ranks above a transaction start
776 		 */
777 		WARN_ON(journal_current_handle());
778 		status = ocfs2_extend_no_holes(gqinode, NULL,
779 			gqinode->i_size + (need_alloc << sb->s_blocksize_bits),
780 			gqinode->i_size);
781 		if (status < 0)
782 			goto out_dq;
783 	}
784 
785 	handle = ocfs2_start_trans(osb,
786 				   ocfs2_calc_global_qinit_credits(sb, type));
787 	if (IS_ERR(handle)) {
788 		status = PTR_ERR(handle);
789 		goto out_dq;
790 	}
791 	status = ocfs2_qinfo_lock(info, ex);
792 	if (status < 0)
793 		goto out_trans;
794 	status = qtree_write_dquot(&info->dqi_gi, dquot);
795 	if (ex && info_dirty(sb_dqinfo(sb, type))) {
796 		err = __ocfs2_global_write_info(sb, type);
797 		if (!status)
798 			status = err;
799 	}
800 	ocfs2_qinfo_unlock(info, ex);
801 out_trans:
802 	ocfs2_commit_trans(osb, handle);
803 out_dq:
804 	ocfs2_unlock_global_qf(info, 1);
805 	if (status < 0)
806 		goto out;
807 
808 	status = ocfs2_create_local_dquot(dquot);
809 	if (status < 0)
810 		goto out;
811 	set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
812 out:
813 	mutex_unlock(&dquot->dq_lock);
814 	mlog_exit(status);
815 	return status;
816 }
817 
818 static int ocfs2_mark_dquot_dirty(struct dquot *dquot)
819 {
820 	unsigned long mask = (1 << (DQ_LASTSET_B + QIF_ILIMITS_B)) |
821 			     (1 << (DQ_LASTSET_B + QIF_BLIMITS_B)) |
822 			     (1 << (DQ_LASTSET_B + QIF_INODES_B)) |
823 			     (1 << (DQ_LASTSET_B + QIF_SPACE_B)) |
824 			     (1 << (DQ_LASTSET_B + QIF_BTIME_B)) |
825 			     (1 << (DQ_LASTSET_B + QIF_ITIME_B));
826 	int sync = 0;
827 	int status;
828 	struct super_block *sb = dquot->dq_sb;
829 	int type = dquot->dq_type;
830 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
831 	handle_t *handle;
832 	struct ocfs2_super *osb = OCFS2_SB(sb);
833 
834 	mlog_entry("id=%u, type=%d", dquot->dq_id, type);
835 
836 	/* In case user set some limits, sync dquot immediately to global
837 	 * quota file so that information propagates quicker */
838 	spin_lock(&dq_data_lock);
839 	if (dquot->dq_flags & mask)
840 		sync = 1;
841 	spin_unlock(&dq_data_lock);
842 	/* This is a slight hack but we can't afford getting global quota
843 	 * lock if we already have a transaction started. */
844 	if (!sync || journal_current_handle()) {
845 		status = ocfs2_write_dquot(dquot);
846 		goto out;
847 	}
848 	status = ocfs2_lock_global_qf(oinfo, 1);
849 	if (status < 0)
850 		goto out;
851 	handle = ocfs2_start_trans(osb, OCFS2_QSYNC_CREDITS);
852 	if (IS_ERR(handle)) {
853 		status = PTR_ERR(handle);
854 		mlog_errno(status);
855 		goto out_ilock;
856 	}
857 	mutex_lock(&sb_dqopt(sb)->dqio_mutex);
858 	status = ocfs2_sync_dquot(dquot);
859 	if (status < 0) {
860 		mlog_errno(status);
861 		goto out_dlock;
862 	}
863 	/* Now write updated local dquot structure */
864 	status = ocfs2_local_write_dquot(dquot);
865 out_dlock:
866 	mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
867 	ocfs2_commit_trans(osb, handle);
868 out_ilock:
869 	ocfs2_unlock_global_qf(oinfo, 1);
870 out:
871 	mlog_exit(status);
872 	return status;
873 }
874 
875 /* This should happen only after set_dqinfo(). */
876 static int ocfs2_write_info(struct super_block *sb, int type)
877 {
878 	handle_t *handle;
879 	int status = 0;
880 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
881 
882 	mlog_entry_void();
883 
884 	status = ocfs2_lock_global_qf(oinfo, 1);
885 	if (status < 0)
886 		goto out;
887 	handle = ocfs2_start_trans(OCFS2_SB(sb), OCFS2_QINFO_WRITE_CREDITS);
888 	if (IS_ERR(handle)) {
889 		status = PTR_ERR(handle);
890 		mlog_errno(status);
891 		goto out_ilock;
892 	}
893 	status = dquot_commit_info(sb, type);
894 	ocfs2_commit_trans(OCFS2_SB(sb), handle);
895 out_ilock:
896 	ocfs2_unlock_global_qf(oinfo, 1);
897 out:
898 	mlog_exit(status);
899 	return status;
900 }
901 
902 static struct dquot *ocfs2_alloc_dquot(struct super_block *sb, int type)
903 {
904 	struct ocfs2_dquot *dquot =
905 				kmem_cache_zalloc(ocfs2_dquot_cachep, GFP_NOFS);
906 
907 	if (!dquot)
908 		return NULL;
909 	return &dquot->dq_dquot;
910 }
911 
912 static void ocfs2_destroy_dquot(struct dquot *dquot)
913 {
914 	kmem_cache_free(ocfs2_dquot_cachep, dquot);
915 }
916 
917 const struct dquot_operations ocfs2_quota_operations = {
918 	/* We never make dquot dirty so .write_dquot is never called */
919 	.acquire_dquot	= ocfs2_acquire_dquot,
920 	.release_dquot	= ocfs2_release_dquot,
921 	.mark_dirty	= ocfs2_mark_dquot_dirty,
922 	.write_info	= ocfs2_write_info,
923 	.alloc_dquot	= ocfs2_alloc_dquot,
924 	.destroy_dquot	= ocfs2_destroy_dquot,
925 };
926 
927 int ocfs2_quota_setup(void)
928 {
929 	ocfs2_quota_wq = create_workqueue("o2quot");
930 	if (!ocfs2_quota_wq)
931 		return -ENOMEM;
932 	return 0;
933 }
934 
935 void ocfs2_quota_shutdown(void)
936 {
937 	if (ocfs2_quota_wq) {
938 		flush_workqueue(ocfs2_quota_wq);
939 		destroy_workqueue(ocfs2_quota_wq);
940 		ocfs2_quota_wq = NULL;
941 	}
942 }
943