xref: /linux/fs/ocfs2/quota_global.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 #include <cluster/masklog.h>
15 
16 #include "ocfs2_fs.h"
17 #include "ocfs2.h"
18 #include "alloc.h"
19 #include "blockcheck.h"
20 #include "inode.h"
21 #include "journal.h"
22 #include "file.h"
23 #include "sysfile.h"
24 #include "dlmglue.h"
25 #include "uptodate.h"
26 #include "super.h"
27 #include "buffer_head_io.h"
28 #include "quota.h"
29 #include "ocfs2_trace.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 void qsync_work_fn(struct work_struct *work);
67 
68 static void ocfs2_global_disk2memdqb(struct dquot *dquot, void *dp)
69 {
70 	struct ocfs2_global_disk_dqblk *d = dp;
71 	struct mem_dqblk *m = &dquot->dq_dqb;
72 
73 	/* Update from disk only entries not set by the admin */
74 	if (!test_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags)) {
75 		m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
76 		m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
77 	}
78 	if (!test_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags))
79 		m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
80 	if (!test_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags)) {
81 		m->dqb_bhardlimit = le64_to_cpu(d->dqb_bhardlimit);
82 		m->dqb_bsoftlimit = le64_to_cpu(d->dqb_bsoftlimit);
83 	}
84 	if (!test_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags))
85 		m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
86 	if (!test_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags))
87 		m->dqb_btime = le64_to_cpu(d->dqb_btime);
88 	if (!test_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags))
89 		m->dqb_itime = le64_to_cpu(d->dqb_itime);
90 	OCFS2_DQUOT(dquot)->dq_use_count = le32_to_cpu(d->dqb_use_count);
91 }
92 
93 static void ocfs2_global_mem2diskdqb(void *dp, struct dquot *dquot)
94 {
95 	struct ocfs2_global_disk_dqblk *d = dp;
96 	struct mem_dqblk *m = &dquot->dq_dqb;
97 
98 	d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
99 	d->dqb_use_count = cpu_to_le32(OCFS2_DQUOT(dquot)->dq_use_count);
100 	d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
101 	d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
102 	d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
103 	d->dqb_bhardlimit = cpu_to_le64(m->dqb_bhardlimit);
104 	d->dqb_bsoftlimit = cpu_to_le64(m->dqb_bsoftlimit);
105 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
106 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
107 	d->dqb_itime = cpu_to_le64(m->dqb_itime);
108 	d->dqb_pad1 = d->dqb_pad2 = 0;
109 }
110 
111 static int ocfs2_global_is_id(void *dp, struct dquot *dquot)
112 {
113 	struct ocfs2_global_disk_dqblk *d = dp;
114 	struct ocfs2_mem_dqinfo *oinfo =
115 			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
116 
117 	if (qtree_entry_unused(&oinfo->dqi_gi, dp))
118 		return 0;
119 
120 	return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
121 				le32_to_cpu(d->dqb_id)),
122 		      dquot->dq_id);
123 }
124 
125 struct qtree_fmt_operations ocfs2_global_ops = {
126 	.mem2disk_dqblk = ocfs2_global_mem2diskdqb,
127 	.disk2mem_dqblk = ocfs2_global_disk2memdqb,
128 	.is_id = ocfs2_global_is_id,
129 };
130 
131 int ocfs2_validate_quota_block(struct super_block *sb, struct buffer_head *bh)
132 {
133 	struct ocfs2_disk_dqtrailer *dqt =
134 		ocfs2_block_dqtrailer(sb->s_blocksize, bh->b_data);
135 
136 	trace_ocfs2_validate_quota_block((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 	/* Read global header */
347 	gqinode = ocfs2_get_system_file_inode(OCFS2_SB(sb), ino[type],
348 			OCFS2_INVALID_SLOT);
349 	if (!gqinode) {
350 		mlog(ML_ERROR, "failed to get global quota inode (type=%d)\n",
351 			type);
352 		status = -EINVAL;
353 		goto out_err;
354 	}
355 	oinfo->dqi_gi.dqi_sb = sb;
356 	oinfo->dqi_gi.dqi_type = type;
357 	ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo);
358 	oinfo->dqi_gi.dqi_entry_size = sizeof(struct ocfs2_global_disk_dqblk);
359 	oinfo->dqi_gi.dqi_ops = &ocfs2_global_ops;
360 	oinfo->dqi_gqi_bh = NULL;
361 	oinfo->dqi_gqi_count = 0;
362 	oinfo->dqi_gqinode = gqinode;
363 	status = ocfs2_lock_global_qf(oinfo, 0);
364 	if (status < 0) {
365 		mlog_errno(status);
366 		goto out_err;
367 	}
368 
369 	status = ocfs2_extent_map_get_blocks(gqinode, 0, &oinfo->dqi_giblk,
370 					     &pcount, NULL);
371 	if (status < 0)
372 		goto out_unlock;
373 
374 	status = ocfs2_qinfo_lock(oinfo, 0);
375 	if (status < 0)
376 		goto out_unlock;
377 	status = sb->s_op->quota_read(sb, type, (char *)&dinfo,
378 				      sizeof(struct ocfs2_global_disk_dqinfo),
379 				      OCFS2_GLOBAL_INFO_OFF);
380 	ocfs2_qinfo_unlock(oinfo, 0);
381 	ocfs2_unlock_global_qf(oinfo, 0);
382 	if (status != sizeof(struct ocfs2_global_disk_dqinfo)) {
383 		mlog(ML_ERROR, "Cannot read global quota info (%d).\n",
384 		     status);
385 		if (status >= 0)
386 			status = -EIO;
387 		mlog_errno(status);
388 		goto out_err;
389 	}
390 	info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
391 	info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
392 	oinfo->dqi_syncms = le32_to_cpu(dinfo.dqi_syncms);
393 	oinfo->dqi_gi.dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
394 	oinfo->dqi_gi.dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
395 	oinfo->dqi_gi.dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
396 	oinfo->dqi_gi.dqi_blocksize_bits = sb->s_blocksize_bits;
397 	oinfo->dqi_gi.dqi_usable_bs = sb->s_blocksize -
398 						OCFS2_QBLK_RESERVED_SPACE;
399 	oinfo->dqi_gi.dqi_qtree_depth = qtree_depth(&oinfo->dqi_gi);
400 	INIT_DELAYED_WORK(&oinfo->dqi_sync_work, qsync_work_fn);
401 	schedule_delayed_work(&oinfo->dqi_sync_work,
402 			      msecs_to_jiffies(oinfo->dqi_syncms));
403 
404 out_err:
405 	return status;
406 out_unlock:
407 	ocfs2_unlock_global_qf(oinfo, 0);
408 	mlog_errno(status);
409 	goto out_err;
410 }
411 
412 /* Write information to global quota file. Expects exlusive lock on quota
413  * file inode and quota info */
414 static int __ocfs2_global_write_info(struct super_block *sb, int type)
415 {
416 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
417 	struct ocfs2_mem_dqinfo *oinfo = info->dqi_priv;
418 	struct ocfs2_global_disk_dqinfo dinfo;
419 	ssize_t size;
420 
421 	spin_lock(&dq_data_lock);
422 	info->dqi_flags &= ~DQF_INFO_DIRTY;
423 	dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
424 	dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
425 	spin_unlock(&dq_data_lock);
426 	dinfo.dqi_syncms = cpu_to_le32(oinfo->dqi_syncms);
427 	dinfo.dqi_blocks = cpu_to_le32(oinfo->dqi_gi.dqi_blocks);
428 	dinfo.dqi_free_blk = cpu_to_le32(oinfo->dqi_gi.dqi_free_blk);
429 	dinfo.dqi_free_entry = cpu_to_le32(oinfo->dqi_gi.dqi_free_entry);
430 	size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
431 				     sizeof(struct ocfs2_global_disk_dqinfo),
432 				     OCFS2_GLOBAL_INFO_OFF);
433 	if (size != sizeof(struct ocfs2_global_disk_dqinfo)) {
434 		mlog(ML_ERROR, "Cannot write global quota info structure\n");
435 		if (size >= 0)
436 			size = -EIO;
437 		return size;
438 	}
439 	return 0;
440 }
441 
442 int ocfs2_global_write_info(struct super_block *sb, int type)
443 {
444 	int err;
445 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
446 
447 	err = ocfs2_qinfo_lock(info, 1);
448 	if (err < 0)
449 		return err;
450 	err = __ocfs2_global_write_info(sb, type);
451 	ocfs2_qinfo_unlock(info, 1);
452 	return err;
453 }
454 
455 static int ocfs2_global_qinit_alloc(struct super_block *sb, int type)
456 {
457 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
458 
459 	/*
460 	 * We may need to allocate tree blocks and a leaf block but not the
461 	 * root block
462 	 */
463 	return oinfo->dqi_gi.dqi_qtree_depth;
464 }
465 
466 static int ocfs2_calc_global_qinit_credits(struct super_block *sb, int type)
467 {
468 	/* We modify all the allocated blocks, tree root, info block and
469 	 * the inode */
470 	return (ocfs2_global_qinit_alloc(sb, type) + 2) *
471 			OCFS2_QUOTA_BLOCK_UPDATE_CREDITS + 1;
472 }
473 
474 /* Sync local information about quota modifications with global quota file.
475  * Caller must have started the transaction and obtained exclusive lock for
476  * global quota file inode */
477 int __ocfs2_sync_dquot(struct dquot *dquot, int freeing)
478 {
479 	int err, err2;
480 	struct super_block *sb = dquot->dq_sb;
481 	int type = dquot->dq_id.type;
482 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
483 	struct ocfs2_global_disk_dqblk dqblk;
484 	s64 spacechange, inodechange;
485 	time_t olditime, oldbtime;
486 
487 	err = sb->s_op->quota_read(sb, type, (char *)&dqblk,
488 				   sizeof(struct ocfs2_global_disk_dqblk),
489 				   dquot->dq_off);
490 	if (err != sizeof(struct ocfs2_global_disk_dqblk)) {
491 		if (err >= 0) {
492 			mlog(ML_ERROR, "Short read from global quota file "
493 				       "(%u read)\n", err);
494 			err = -EIO;
495 		}
496 		goto out;
497 	}
498 
499 	/* Update space and inode usage. Get also other information from
500 	 * global quota file so that we don't overwrite any changes there.
501 	 * We are */
502 	spin_lock(&dq_data_lock);
503 	spacechange = dquot->dq_dqb.dqb_curspace -
504 					OCFS2_DQUOT(dquot)->dq_origspace;
505 	inodechange = dquot->dq_dqb.dqb_curinodes -
506 					OCFS2_DQUOT(dquot)->dq_originodes;
507 	olditime = dquot->dq_dqb.dqb_itime;
508 	oldbtime = dquot->dq_dqb.dqb_btime;
509 	ocfs2_global_disk2memdqb(dquot, &dqblk);
510 	trace_ocfs2_sync_dquot(from_kqid(&init_user_ns, dquot->dq_id),
511 			       dquot->dq_dqb.dqb_curspace,
512 			       (long long)spacechange,
513 			       dquot->dq_dqb.dqb_curinodes,
514 			       (long long)inodechange);
515 	if (!test_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags))
516 		dquot->dq_dqb.dqb_curspace += spacechange;
517 	if (!test_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags))
518 		dquot->dq_dqb.dqb_curinodes += inodechange;
519 	/* Set properly space grace time... */
520 	if (dquot->dq_dqb.dqb_bsoftlimit &&
521 	    dquot->dq_dqb.dqb_curspace > dquot->dq_dqb.dqb_bsoftlimit) {
522 		if (!test_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags) &&
523 		    oldbtime > 0) {
524 			if (dquot->dq_dqb.dqb_btime > 0)
525 				dquot->dq_dqb.dqb_btime =
526 					min(dquot->dq_dqb.dqb_btime, oldbtime);
527 			else
528 				dquot->dq_dqb.dqb_btime = oldbtime;
529 		}
530 	} else {
531 		dquot->dq_dqb.dqb_btime = 0;
532 		clear_bit(DQ_BLKS_B, &dquot->dq_flags);
533 	}
534 	/* Set properly inode grace time... */
535 	if (dquot->dq_dqb.dqb_isoftlimit &&
536 	    dquot->dq_dqb.dqb_curinodes > dquot->dq_dqb.dqb_isoftlimit) {
537 		if (!test_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags) &&
538 		    olditime > 0) {
539 			if (dquot->dq_dqb.dqb_itime > 0)
540 				dquot->dq_dqb.dqb_itime =
541 					min(dquot->dq_dqb.dqb_itime, olditime);
542 			else
543 				dquot->dq_dqb.dqb_itime = olditime;
544 		}
545 	} else {
546 		dquot->dq_dqb.dqb_itime = 0;
547 		clear_bit(DQ_INODES_B, &dquot->dq_flags);
548 	}
549 	/* All information is properly updated, clear the flags */
550 	__clear_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
551 	__clear_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
552 	__clear_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
553 	__clear_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
554 	__clear_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
555 	__clear_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
556 	OCFS2_DQUOT(dquot)->dq_origspace = dquot->dq_dqb.dqb_curspace;
557 	OCFS2_DQUOT(dquot)->dq_originodes = dquot->dq_dqb.dqb_curinodes;
558 	spin_unlock(&dq_data_lock);
559 	err = ocfs2_qinfo_lock(info, freeing);
560 	if (err < 0) {
561 		mlog(ML_ERROR, "Failed to lock quota info, losing quota write"
562 			       " (type=%d, id=%u)\n", dquot->dq_id.type,
563 			       (unsigned)from_kqid(&init_user_ns, dquot->dq_id));
564 		goto out;
565 	}
566 	if (freeing)
567 		OCFS2_DQUOT(dquot)->dq_use_count--;
568 	err = qtree_write_dquot(&info->dqi_gi, dquot);
569 	if (err < 0)
570 		goto out_qlock;
571 	if (freeing && !OCFS2_DQUOT(dquot)->dq_use_count) {
572 		err = qtree_release_dquot(&info->dqi_gi, dquot);
573 		if (info_dirty(sb_dqinfo(sb, type))) {
574 			err2 = __ocfs2_global_write_info(sb, type);
575 			if (!err)
576 				err = err2;
577 		}
578 	}
579 out_qlock:
580 	ocfs2_qinfo_unlock(info, freeing);
581 out:
582 	if (err < 0)
583 		mlog_errno(err);
584 	return err;
585 }
586 
587 /*
588  *  Functions for periodic syncing of dquots with global file
589  */
590 static int ocfs2_sync_dquot_helper(struct dquot *dquot, unsigned long type)
591 {
592 	handle_t *handle;
593 	struct super_block *sb = dquot->dq_sb;
594 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
595 	struct ocfs2_super *osb = OCFS2_SB(sb);
596 	int status = 0;
597 
598 	trace_ocfs2_sync_dquot_helper(from_kqid(&init_user_ns, dquot->dq_id),
599 				      dquot->dq_id.type,
600 				      type, sb->s_id);
601 	if (type != dquot->dq_id.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 	return status;
627 }
628 
629 static void qsync_work_fn(struct work_struct *work)
630 {
631 	struct ocfs2_mem_dqinfo *oinfo = container_of(work,
632 						      struct ocfs2_mem_dqinfo,
633 						      dqi_sync_work.work);
634 	struct super_block *sb = oinfo->dqi_gqinode->i_sb;
635 
636 	dquot_scan_active(sb, ocfs2_sync_dquot_helper, oinfo->dqi_type);
637 	schedule_delayed_work(&oinfo->dqi_sync_work,
638 			      msecs_to_jiffies(oinfo->dqi_syncms));
639 }
640 
641 /*
642  *  Wrappers for generic quota functions
643  */
644 
645 static int ocfs2_write_dquot(struct dquot *dquot)
646 {
647 	handle_t *handle;
648 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
649 	int status = 0;
650 
651 	trace_ocfs2_write_dquot(from_kqid(&init_user_ns, dquot->dq_id),
652 				dquot->dq_id.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 	return status;
666 }
667 
668 static int ocfs2_calc_qdel_credits(struct super_block *sb, int type)
669 {
670 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
671 	/*
672 	 * We modify tree, leaf block, global info, local chunk header,
673 	 * global and local inode; OCFS2_QINFO_WRITE_CREDITS already
674 	 * accounts for inode update
675 	 */
676 	return (oinfo->dqi_gi.dqi_qtree_depth + 2) *
677 	       OCFS2_QUOTA_BLOCK_UPDATE_CREDITS +
678 	       OCFS2_QINFO_WRITE_CREDITS +
679 	       OCFS2_INODE_UPDATE_CREDITS;
680 }
681 
682 static int ocfs2_release_dquot(struct dquot *dquot)
683 {
684 	handle_t *handle;
685 	struct ocfs2_mem_dqinfo *oinfo =
686 			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
687 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
688 	int status = 0;
689 
690 	trace_ocfs2_release_dquot(from_kqid(&init_user_ns, dquot->dq_id),
691 				  dquot->dq_id.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_id.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 	if (status)
728 		mlog_errno(status);
729 	return status;
730 }
731 
732 /*
733  * Read global dquot structure from disk or create it if it does
734  * not exist. Also update use count of the global structure and
735  * create structure in node-local quota file.
736  */
737 static int ocfs2_acquire_dquot(struct dquot *dquot)
738 {
739 	int status = 0, err;
740 	int ex = 0;
741 	struct super_block *sb = dquot->dq_sb;
742 	struct ocfs2_super *osb = OCFS2_SB(sb);
743 	int type = dquot->dq_id.type;
744 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
745 	struct inode *gqinode = info->dqi_gqinode;
746 	int need_alloc = ocfs2_global_qinit_alloc(sb, type);
747 	handle_t *handle;
748 
749 	trace_ocfs2_acquire_dquot(from_kqid(&init_user_ns, dquot->dq_id),
750 				  type);
751 	mutex_lock(&dquot->dq_lock);
752 	/*
753 	 * We need an exclusive lock, because we're going to update use count
754 	 * and instantiate possibly new dquot structure
755 	 */
756 	status = ocfs2_lock_global_qf(info, 1);
757 	if (status < 0)
758 		goto out;
759 	if (!test_bit(DQ_READ_B, &dquot->dq_flags)) {
760 		status = ocfs2_qinfo_lock(info, 0);
761 		if (status < 0)
762 			goto out_dq;
763 		status = qtree_read_dquot(&info->dqi_gi, dquot);
764 		ocfs2_qinfo_unlock(info, 0);
765 		if (status < 0)
766 			goto out_dq;
767 	}
768 	set_bit(DQ_READ_B, &dquot->dq_flags);
769 
770 	OCFS2_DQUOT(dquot)->dq_use_count++;
771 	OCFS2_DQUOT(dquot)->dq_origspace = dquot->dq_dqb.dqb_curspace;
772 	OCFS2_DQUOT(dquot)->dq_originodes = dquot->dq_dqb.dqb_curinodes;
773 	if (!dquot->dq_off) {	/* No real quota entry? */
774 		ex = 1;
775 		/*
776 		 * Add blocks to quota file before we start a transaction since
777 		 * locking allocators ranks above a transaction start
778 		 */
779 		WARN_ON(journal_current_handle());
780 		status = ocfs2_extend_no_holes(gqinode, NULL,
781 			gqinode->i_size + (need_alloc << sb->s_blocksize_bits),
782 			gqinode->i_size);
783 		if (status < 0)
784 			goto out_dq;
785 	}
786 
787 	handle = ocfs2_start_trans(osb,
788 				   ocfs2_calc_global_qinit_credits(sb, type));
789 	if (IS_ERR(handle)) {
790 		status = PTR_ERR(handle);
791 		goto out_dq;
792 	}
793 	status = ocfs2_qinfo_lock(info, ex);
794 	if (status < 0)
795 		goto out_trans;
796 	status = qtree_write_dquot(&info->dqi_gi, dquot);
797 	if (ex && info_dirty(sb_dqinfo(sb, type))) {
798 		err = __ocfs2_global_write_info(sb, type);
799 		if (!status)
800 			status = err;
801 	}
802 	ocfs2_qinfo_unlock(info, ex);
803 out_trans:
804 	ocfs2_commit_trans(osb, handle);
805 out_dq:
806 	ocfs2_unlock_global_qf(info, 1);
807 	if (status < 0)
808 		goto out;
809 
810 	status = ocfs2_create_local_dquot(dquot);
811 	if (status < 0)
812 		goto out;
813 	set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
814 out:
815 	mutex_unlock(&dquot->dq_lock);
816 	if (status)
817 		mlog_errno(status);
818 	return status;
819 }
820 
821 static int ocfs2_mark_dquot_dirty(struct dquot *dquot)
822 {
823 	unsigned long mask = (1 << (DQ_LASTSET_B + QIF_ILIMITS_B)) |
824 			     (1 << (DQ_LASTSET_B + QIF_BLIMITS_B)) |
825 			     (1 << (DQ_LASTSET_B + QIF_INODES_B)) |
826 			     (1 << (DQ_LASTSET_B + QIF_SPACE_B)) |
827 			     (1 << (DQ_LASTSET_B + QIF_BTIME_B)) |
828 			     (1 << (DQ_LASTSET_B + QIF_ITIME_B));
829 	int sync = 0;
830 	int status;
831 	struct super_block *sb = dquot->dq_sb;
832 	int type = dquot->dq_id.type;
833 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
834 	handle_t *handle;
835 	struct ocfs2_super *osb = OCFS2_SB(sb);
836 
837 	trace_ocfs2_mark_dquot_dirty(from_kqid(&init_user_ns, dquot->dq_id),
838 				     type);
839 
840 	/* In case user set some limits, sync dquot immediately to global
841 	 * quota file so that information propagates quicker */
842 	spin_lock(&dq_data_lock);
843 	if (dquot->dq_flags & mask)
844 		sync = 1;
845 	spin_unlock(&dq_data_lock);
846 	/* This is a slight hack but we can't afford getting global quota
847 	 * lock if we already have a transaction started. */
848 	if (!sync || journal_current_handle()) {
849 		status = ocfs2_write_dquot(dquot);
850 		goto out;
851 	}
852 	status = ocfs2_lock_global_qf(oinfo, 1);
853 	if (status < 0)
854 		goto out;
855 	handle = ocfs2_start_trans(osb, OCFS2_QSYNC_CREDITS);
856 	if (IS_ERR(handle)) {
857 		status = PTR_ERR(handle);
858 		mlog_errno(status);
859 		goto out_ilock;
860 	}
861 	mutex_lock(&sb_dqopt(sb)->dqio_mutex);
862 	status = ocfs2_sync_dquot(dquot);
863 	if (status < 0) {
864 		mlog_errno(status);
865 		goto out_dlock;
866 	}
867 	/* Now write updated local dquot structure */
868 	status = ocfs2_local_write_dquot(dquot);
869 out_dlock:
870 	mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
871 	ocfs2_commit_trans(osb, handle);
872 out_ilock:
873 	ocfs2_unlock_global_qf(oinfo, 1);
874 out:
875 	if (status)
876 		mlog_errno(status);
877 	return status;
878 }
879 
880 /* This should happen only after set_dqinfo(). */
881 static int ocfs2_write_info(struct super_block *sb, int type)
882 {
883 	handle_t *handle;
884 	int status = 0;
885 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
886 
887 	status = ocfs2_lock_global_qf(oinfo, 1);
888 	if (status < 0)
889 		goto out;
890 	handle = ocfs2_start_trans(OCFS2_SB(sb), OCFS2_QINFO_WRITE_CREDITS);
891 	if (IS_ERR(handle)) {
892 		status = PTR_ERR(handle);
893 		mlog_errno(status);
894 		goto out_ilock;
895 	}
896 	status = dquot_commit_info(sb, type);
897 	ocfs2_commit_trans(OCFS2_SB(sb), handle);
898 out_ilock:
899 	ocfs2_unlock_global_qf(oinfo, 1);
900 out:
901 	if (status)
902 		mlog_errno(status);
903 	return status;
904 }
905 
906 static struct dquot *ocfs2_alloc_dquot(struct super_block *sb, int type)
907 {
908 	struct ocfs2_dquot *dquot =
909 				kmem_cache_zalloc(ocfs2_dquot_cachep, GFP_NOFS);
910 
911 	if (!dquot)
912 		return NULL;
913 	return &dquot->dq_dquot;
914 }
915 
916 static void ocfs2_destroy_dquot(struct dquot *dquot)
917 {
918 	kmem_cache_free(ocfs2_dquot_cachep, dquot);
919 }
920 
921 const struct dquot_operations ocfs2_quota_operations = {
922 	/* We never make dquot dirty so .write_dquot is never called */
923 	.acquire_dquot	= ocfs2_acquire_dquot,
924 	.release_dquot	= ocfs2_release_dquot,
925 	.mark_dirty	= ocfs2_mark_dquot_dirty,
926 	.write_info	= ocfs2_write_info,
927 	.alloc_dquot	= ocfs2_alloc_dquot,
928 	.destroy_dquot	= ocfs2_destroy_dquot,
929 };
930