xref: /openbmc/linux/fs/ocfs2/quota_global.c (revision dea54fba)
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 #include <linux/llist.h>
14 
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 #include "ocfs2_trace.h"
31 
32 /*
33  * Locking of quotas with OCFS2 is rather complex. Here are rules that
34  * should be obeyed by all the functions:
35  * - any write of quota structure (either to local or global file) is protected
36  *   by dqio_mutex or dquot->dq_lock.
37  * - any modification of global quota file holds inode cluster lock, i_mutex,
38  *   and ip_alloc_sem of the global quota file (achieved by
39  *   ocfs2_lock_global_qf). It also has to hold qinfo_lock.
40  * - an allocation of new blocks for local quota file is protected by
41  *   its ip_alloc_sem
42  *
43  * A rough sketch of locking dependencies (lf = local file, gf = global file):
44  * Normal filesystem operation:
45  *   start_trans -> dqio_mutex -> write to lf
46  * Syncing of local and global file:
47  *   ocfs2_lock_global_qf -> start_trans -> dqio_mutex -> qinfo_lock ->
48  *     write to gf
49  *						       -> write to lf
50  * Acquire dquot for the first time:
51  *   dq_lock -> ocfs2_lock_global_qf -> qinfo_lock -> read from gf
52  *				     -> alloc space for gf
53  *				     -> start_trans -> qinfo_lock -> write to gf
54  *	     -> ip_alloc_sem of lf -> alloc space for lf
55  *	     -> write to lf
56  * Release last reference to dquot:
57  *   dq_lock -> ocfs2_lock_global_qf -> start_trans -> qinfo_lock -> write to gf
58  *	     -> write to lf
59  * Note that all the above operations also hold the inode cluster lock of lf.
60  * Recovery:
61  *   inode cluster lock of recovered lf
62  *     -> read bitmaps -> ip_alloc_sem of lf
63  *     -> ocfs2_lock_global_qf -> start_trans -> dqio_mutex -> qinfo_lock ->
64  *        write to gf
65  */
66 
67 static void qsync_work_fn(struct work_struct *work);
68 
69 static void ocfs2_global_disk2memdqb(struct dquot *dquot, void *dp)
70 {
71 	struct ocfs2_global_disk_dqblk *d = dp;
72 	struct mem_dqblk *m = &dquot->dq_dqb;
73 
74 	/* Update from disk only entries not set by the admin */
75 	if (!test_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags)) {
76 		m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
77 		m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
78 	}
79 	if (!test_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags))
80 		m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
81 	if (!test_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags)) {
82 		m->dqb_bhardlimit = le64_to_cpu(d->dqb_bhardlimit);
83 		m->dqb_bsoftlimit = le64_to_cpu(d->dqb_bsoftlimit);
84 	}
85 	if (!test_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags))
86 		m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
87 	if (!test_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags))
88 		m->dqb_btime = le64_to_cpu(d->dqb_btime);
89 	if (!test_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags))
90 		m->dqb_itime = le64_to_cpu(d->dqb_itime);
91 	OCFS2_DQUOT(dquot)->dq_use_count = le32_to_cpu(d->dqb_use_count);
92 }
93 
94 static void ocfs2_global_mem2diskdqb(void *dp, struct dquot *dquot)
95 {
96 	struct ocfs2_global_disk_dqblk *d = dp;
97 	struct mem_dqblk *m = &dquot->dq_dqb;
98 
99 	d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
100 	d->dqb_use_count = cpu_to_le32(OCFS2_DQUOT(dquot)->dq_use_count);
101 	d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
102 	d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
103 	d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
104 	d->dqb_bhardlimit = cpu_to_le64(m->dqb_bhardlimit);
105 	d->dqb_bsoftlimit = cpu_to_le64(m->dqb_bsoftlimit);
106 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
107 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
108 	d->dqb_itime = cpu_to_le64(m->dqb_itime);
109 	d->dqb_pad1 = d->dqb_pad2 = 0;
110 }
111 
112 static int ocfs2_global_is_id(void *dp, struct dquot *dquot)
113 {
114 	struct ocfs2_global_disk_dqblk *d = dp;
115 	struct ocfs2_mem_dqinfo *oinfo =
116 			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
117 
118 	if (qtree_entry_unused(&oinfo->dqi_gi, dp))
119 		return 0;
120 
121 	return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
122 				le32_to_cpu(d->dqb_id)),
123 		      dquot->dq_id);
124 }
125 
126 const struct qtree_fmt_operations ocfs2_global_ops = {
127 	.mem2disk_dqblk = ocfs2_global_mem2diskdqb,
128 	.disk2mem_dqblk = ocfs2_global_disk2memdqb,
129 	.is_id = ocfs2_global_is_id,
130 };
131 
132 int ocfs2_validate_quota_block(struct super_block *sb, struct buffer_head *bh)
133 {
134 	struct ocfs2_disk_dqtrailer *dqt =
135 		ocfs2_block_dqtrailer(sb->s_blocksize, bh->b_data);
136 
137 	trace_ocfs2_validate_quota_block((unsigned long long)bh->b_blocknr);
138 
139 	BUG_ON(!buffer_uptodate(bh));
140 
141 	/*
142 	 * If the ecc fails, we return the error but otherwise
143 	 * leave the filesystem running.  We know any error is
144 	 * local to this block.
145 	 */
146 	return ocfs2_validate_meta_ecc(sb, bh->b_data, &dqt->dq_check);
147 }
148 
149 int ocfs2_read_quota_phys_block(struct inode *inode, u64 p_block,
150 				struct buffer_head **bhp)
151 {
152 	int rc;
153 
154 	*bhp = NULL;
155 	rc = ocfs2_read_blocks(INODE_CACHE(inode), p_block, 1, bhp, 0,
156 			       ocfs2_validate_quota_block);
157 	if (rc)
158 		mlog_errno(rc);
159 	return rc;
160 }
161 
162 /* Read data from global quotafile - avoid pagecache and such because we cannot
163  * afford acquiring the locks... We use quota cluster lock to serialize
164  * operations. Caller is responsible for acquiring it. */
165 ssize_t ocfs2_quota_read(struct super_block *sb, int type, char *data,
166 			 size_t len, loff_t off)
167 {
168 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
169 	struct inode *gqinode = oinfo->dqi_gqinode;
170 	loff_t i_size = i_size_read(gqinode);
171 	int offset = off & (sb->s_blocksize - 1);
172 	sector_t blk = off >> sb->s_blocksize_bits;
173 	int err = 0;
174 	struct buffer_head *bh;
175 	size_t toread, tocopy;
176 	u64 pblock = 0, pcount = 0;
177 
178 	if (off > i_size)
179 		return 0;
180 	if (off + len > i_size)
181 		len = i_size - off;
182 	toread = len;
183 	while (toread > 0) {
184 		tocopy = min_t(size_t, (sb->s_blocksize - offset), toread);
185 		if (!pcount) {
186 			err = ocfs2_extent_map_get_blocks(gqinode, blk, &pblock,
187 							  &pcount, NULL);
188 			if (err) {
189 				mlog_errno(err);
190 				return err;
191 			}
192 		} else {
193 			pcount--;
194 			pblock++;
195 		}
196 		bh = NULL;
197 		err = ocfs2_read_quota_phys_block(gqinode, pblock, &bh);
198 		if (err) {
199 			mlog_errno(err);
200 			return err;
201 		}
202 		memcpy(data, bh->b_data + offset, tocopy);
203 		brelse(bh);
204 		offset = 0;
205 		toread -= tocopy;
206 		data += tocopy;
207 		blk++;
208 	}
209 	return len;
210 }
211 
212 /* Write to quotafile (we know the transaction is already started and has
213  * enough credits) */
214 ssize_t ocfs2_quota_write(struct super_block *sb, int type,
215 			  const char *data, size_t len, loff_t off)
216 {
217 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
218 	struct ocfs2_mem_dqinfo *oinfo = info->dqi_priv;
219 	struct inode *gqinode = oinfo->dqi_gqinode;
220 	int offset = off & (sb->s_blocksize - 1);
221 	sector_t blk = off >> sb->s_blocksize_bits;
222 	int err = 0, new = 0, ja_type;
223 	struct buffer_head *bh = NULL;
224 	handle_t *handle = journal_current_handle();
225 	u64 pblock, pcount;
226 
227 	if (!handle) {
228 		mlog(ML_ERROR, "Quota write (off=%llu, len=%llu) cancelled "
229 		     "because transaction was not started.\n",
230 		     (unsigned long long)off, (unsigned long long)len);
231 		return -EIO;
232 	}
233 	if (len > sb->s_blocksize - OCFS2_QBLK_RESERVED_SPACE - offset) {
234 		WARN_ON(1);
235 		len = sb->s_blocksize - OCFS2_QBLK_RESERVED_SPACE - offset;
236 	}
237 
238 	if (i_size_read(gqinode) < off + len) {
239 		loff_t rounded_end =
240 				ocfs2_align_bytes_to_blocks(sb, off + len);
241 
242 		/* Space is already allocated in ocfs2_acquire_dquot() */
243 		err = ocfs2_simple_size_update(gqinode,
244 					       oinfo->dqi_gqi_bh,
245 					       rounded_end);
246 		if (err < 0)
247 			goto out;
248 		new = 1;
249 	}
250 	err = ocfs2_extent_map_get_blocks(gqinode, blk, &pblock, &pcount, NULL);
251 	if (err) {
252 		mlog_errno(err);
253 		goto out;
254 	}
255 	/* Not rewriting whole block? */
256 	if ((offset || len < sb->s_blocksize - OCFS2_QBLK_RESERVED_SPACE) &&
257 	    !new) {
258 		err = ocfs2_read_quota_phys_block(gqinode, pblock, &bh);
259 		ja_type = OCFS2_JOURNAL_ACCESS_WRITE;
260 	} else {
261 		bh = sb_getblk(sb, pblock);
262 		if (!bh)
263 			err = -ENOMEM;
264 		ja_type = OCFS2_JOURNAL_ACCESS_CREATE;
265 	}
266 	if (err) {
267 		mlog_errno(err);
268 		goto out;
269 	}
270 	lock_buffer(bh);
271 	if (new)
272 		memset(bh->b_data, 0, sb->s_blocksize);
273 	memcpy(bh->b_data + offset, data, len);
274 	flush_dcache_page(bh->b_page);
275 	set_buffer_uptodate(bh);
276 	unlock_buffer(bh);
277 	ocfs2_set_buffer_uptodate(INODE_CACHE(gqinode), bh);
278 	err = ocfs2_journal_access_dq(handle, INODE_CACHE(gqinode), bh,
279 				      ja_type);
280 	if (err < 0) {
281 		brelse(bh);
282 		goto out;
283 	}
284 	ocfs2_journal_dirty(handle, bh);
285 	brelse(bh);
286 out:
287 	if (err) {
288 		mlog_errno(err);
289 		return err;
290 	}
291 	gqinode->i_version++;
292 	ocfs2_mark_inode_dirty(handle, gqinode, oinfo->dqi_gqi_bh);
293 	return len;
294 }
295 
296 int ocfs2_lock_global_qf(struct ocfs2_mem_dqinfo *oinfo, int ex)
297 {
298 	int status;
299 	struct buffer_head *bh = NULL;
300 
301 	status = ocfs2_inode_lock(oinfo->dqi_gqinode, &bh, ex);
302 	if (status < 0)
303 		return status;
304 	spin_lock(&dq_data_lock);
305 	if (!oinfo->dqi_gqi_count++)
306 		oinfo->dqi_gqi_bh = bh;
307 	else
308 		WARN_ON(bh != oinfo->dqi_gqi_bh);
309 	spin_unlock(&dq_data_lock);
310 	if (ex) {
311 		inode_lock(oinfo->dqi_gqinode);
312 		down_write(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
313 	} else {
314 		down_read(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
315 	}
316 	return 0;
317 }
318 
319 void ocfs2_unlock_global_qf(struct ocfs2_mem_dqinfo *oinfo, int ex)
320 {
321 	if (ex) {
322 		up_write(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
323 		inode_unlock(oinfo->dqi_gqinode);
324 	} else {
325 		up_read(&OCFS2_I(oinfo->dqi_gqinode)->ip_alloc_sem);
326 	}
327 	ocfs2_inode_unlock(oinfo->dqi_gqinode, ex);
328 	brelse(oinfo->dqi_gqi_bh);
329 	spin_lock(&dq_data_lock);
330 	if (!--oinfo->dqi_gqi_count)
331 		oinfo->dqi_gqi_bh = NULL;
332 	spin_unlock(&dq_data_lock);
333 }
334 
335 /* Read information header from global quota file */
336 int ocfs2_global_read_info(struct super_block *sb, int type)
337 {
338 	struct inode *gqinode = NULL;
339 	unsigned int ino[OCFS2_MAXQUOTAS] = { USER_QUOTA_SYSTEM_INODE,
340 					      GROUP_QUOTA_SYSTEM_INODE };
341 	struct ocfs2_global_disk_dqinfo dinfo;
342 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
343 	struct ocfs2_mem_dqinfo *oinfo = info->dqi_priv;
344 	u64 pcount;
345 	int status;
346 
347 	/* Read global header */
348 	gqinode = ocfs2_get_system_file_inode(OCFS2_SB(sb), ino[type],
349 			OCFS2_INVALID_SLOT);
350 	if (!gqinode) {
351 		mlog(ML_ERROR, "failed to get global quota inode (type=%d)\n",
352 			type);
353 		status = -EINVAL;
354 		goto out_err;
355 	}
356 	oinfo->dqi_gi.dqi_sb = sb;
357 	oinfo->dqi_gi.dqi_type = type;
358 	ocfs2_qinfo_lock_res_init(&oinfo->dqi_gqlock, oinfo);
359 	oinfo->dqi_gi.dqi_entry_size = sizeof(struct ocfs2_global_disk_dqblk);
360 	oinfo->dqi_gi.dqi_ops = &ocfs2_global_ops;
361 	oinfo->dqi_gqi_bh = NULL;
362 	oinfo->dqi_gqi_count = 0;
363 	oinfo->dqi_gqinode = gqinode;
364 	status = ocfs2_lock_global_qf(oinfo, 0);
365 	if (status < 0) {
366 		mlog_errno(status);
367 		goto out_err;
368 	}
369 
370 	status = ocfs2_extent_map_get_blocks(gqinode, 0, &oinfo->dqi_giblk,
371 					     &pcount, NULL);
372 	if (status < 0)
373 		goto out_unlock;
374 
375 	status = ocfs2_qinfo_lock(oinfo, 0);
376 	if (status < 0)
377 		goto out_unlock;
378 	status = sb->s_op->quota_read(sb, type, (char *)&dinfo,
379 				      sizeof(struct ocfs2_global_disk_dqinfo),
380 				      OCFS2_GLOBAL_INFO_OFF);
381 	ocfs2_qinfo_unlock(oinfo, 0);
382 	ocfs2_unlock_global_qf(oinfo, 0);
383 	if (status != sizeof(struct ocfs2_global_disk_dqinfo)) {
384 		mlog(ML_ERROR, "Cannot read global quota info (%d).\n",
385 		     status);
386 		if (status >= 0)
387 			status = -EIO;
388 		mlog_errno(status);
389 		goto out_err;
390 	}
391 	info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
392 	info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
393 	oinfo->dqi_syncms = le32_to_cpu(dinfo.dqi_syncms);
394 	oinfo->dqi_gi.dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
395 	oinfo->dqi_gi.dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
396 	oinfo->dqi_gi.dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
397 	oinfo->dqi_gi.dqi_blocksize_bits = sb->s_blocksize_bits;
398 	oinfo->dqi_gi.dqi_usable_bs = sb->s_blocksize -
399 						OCFS2_QBLK_RESERVED_SPACE;
400 	oinfo->dqi_gi.dqi_qtree_depth = qtree_depth(&oinfo->dqi_gi);
401 	INIT_DELAYED_WORK(&oinfo->dqi_sync_work, qsync_work_fn);
402 	schedule_delayed_work(&oinfo->dqi_sync_work,
403 			      msecs_to_jiffies(oinfo->dqi_syncms));
404 
405 out_err:
406 	return status;
407 out_unlock:
408 	ocfs2_unlock_global_qf(oinfo, 0);
409 	mlog_errno(status);
410 	goto out_err;
411 }
412 
413 /* Write information to global quota file. Expects exlusive lock on quota
414  * file inode and quota info */
415 static int __ocfs2_global_write_info(struct super_block *sb, int type)
416 {
417 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
418 	struct ocfs2_mem_dqinfo *oinfo = info->dqi_priv;
419 	struct ocfs2_global_disk_dqinfo dinfo;
420 	ssize_t size;
421 
422 	spin_lock(&dq_data_lock);
423 	info->dqi_flags &= ~DQF_INFO_DIRTY;
424 	dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
425 	dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
426 	spin_unlock(&dq_data_lock);
427 	dinfo.dqi_syncms = cpu_to_le32(oinfo->dqi_syncms);
428 	dinfo.dqi_blocks = cpu_to_le32(oinfo->dqi_gi.dqi_blocks);
429 	dinfo.dqi_free_blk = cpu_to_le32(oinfo->dqi_gi.dqi_free_blk);
430 	dinfo.dqi_free_entry = cpu_to_le32(oinfo->dqi_gi.dqi_free_entry);
431 	size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
432 				     sizeof(struct ocfs2_global_disk_dqinfo),
433 				     OCFS2_GLOBAL_INFO_OFF);
434 	if (size != sizeof(struct ocfs2_global_disk_dqinfo)) {
435 		mlog(ML_ERROR, "Cannot write global quota info structure\n");
436 		if (size >= 0)
437 			size = -EIO;
438 		return size;
439 	}
440 	return 0;
441 }
442 
443 int ocfs2_global_write_info(struct super_block *sb, int type)
444 {
445 	int err;
446 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
447 
448 	err = ocfs2_qinfo_lock(info, 1);
449 	if (err < 0)
450 		return err;
451 	err = __ocfs2_global_write_info(sb, type);
452 	ocfs2_qinfo_unlock(info, 1);
453 	return err;
454 }
455 
456 static int ocfs2_global_qinit_alloc(struct super_block *sb, int type)
457 {
458 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
459 
460 	/*
461 	 * We may need to allocate tree blocks and a leaf block but not the
462 	 * root block
463 	 */
464 	return oinfo->dqi_gi.dqi_qtree_depth;
465 }
466 
467 static int ocfs2_calc_global_qinit_credits(struct super_block *sb, int type)
468 {
469 	/* We modify all the allocated blocks, tree root, info block and
470 	 * the inode */
471 	return (ocfs2_global_qinit_alloc(sb, type) + 2) *
472 			OCFS2_QUOTA_BLOCK_UPDATE_CREDITS + 1;
473 }
474 
475 /* Sync local information about quota modifications with global quota file.
476  * Caller must have started the transaction and obtained exclusive lock for
477  * global quota file inode */
478 int __ocfs2_sync_dquot(struct dquot *dquot, int freeing)
479 {
480 	int err, err2;
481 	struct super_block *sb = dquot->dq_sb;
482 	int type = dquot->dq_id.type;
483 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
484 	struct ocfs2_global_disk_dqblk dqblk;
485 	s64 spacechange, inodechange;
486 	time64_t olditime, oldbtime;
487 
488 	err = sb->s_op->quota_read(sb, type, (char *)&dqblk,
489 				   sizeof(struct ocfs2_global_disk_dqblk),
490 				   dquot->dq_off);
491 	if (err != sizeof(struct ocfs2_global_disk_dqblk)) {
492 		if (err >= 0) {
493 			mlog(ML_ERROR, "Short read from global quota file "
494 				       "(%u read)\n", err);
495 			err = -EIO;
496 		}
497 		goto out;
498 	}
499 
500 	/* Update space and inode usage. Get also other information from
501 	 * global quota file so that we don't overwrite any changes there.
502 	 * We are */
503 	spin_lock(&dq_data_lock);
504 	spacechange = dquot->dq_dqb.dqb_curspace -
505 					OCFS2_DQUOT(dquot)->dq_origspace;
506 	inodechange = dquot->dq_dqb.dqb_curinodes -
507 					OCFS2_DQUOT(dquot)->dq_originodes;
508 	olditime = dquot->dq_dqb.dqb_itime;
509 	oldbtime = dquot->dq_dqb.dqb_btime;
510 	ocfs2_global_disk2memdqb(dquot, &dqblk);
511 	trace_ocfs2_sync_dquot(from_kqid(&init_user_ns, dquot->dq_id),
512 			       dquot->dq_dqb.dqb_curspace,
513 			       (long long)spacechange,
514 			       dquot->dq_dqb.dqb_curinodes,
515 			       (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, losing quota write"
563 			       " (type=%d, id=%u)\n", dquot->dq_id.type,
564 			       (unsigned)from_kqid(&init_user_ns, 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 	trace_ocfs2_sync_dquot_helper(from_kqid(&init_user_ns, dquot->dq_id),
600 				      dquot->dq_id.type,
601 				      type, sb->s_id);
602 	if (type != dquot->dq_id.type)
603 		goto out;
604 	status = ocfs2_lock_global_qf(oinfo, 1);
605 	if (status < 0)
606 		goto out;
607 
608 	handle = ocfs2_start_trans(osb, OCFS2_QSYNC_CREDITS);
609 	if (IS_ERR(handle)) {
610 		status = PTR_ERR(handle);
611 		mlog_errno(status);
612 		goto out_ilock;
613 	}
614 	mutex_lock(&sb_dqopt(sb)->dqio_mutex);
615 	status = ocfs2_sync_dquot(dquot);
616 	if (status < 0)
617 		mlog_errno(status);
618 	/* We have to write local structure as well... */
619 	status = ocfs2_local_write_dquot(dquot);
620 	if (status < 0)
621 		mlog_errno(status);
622 	mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
623 	ocfs2_commit_trans(osb, handle);
624 out_ilock:
625 	ocfs2_unlock_global_qf(oinfo, 1);
626 out:
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 	/*
638 	 * We have to be careful here not to deadlock on s_umount as umount
639 	 * disabling quotas may be in progress and it waits for this work to
640 	 * complete. If trylock fails, we'll do the sync next time...
641 	 */
642 	if (down_read_trylock(&sb->s_umount)) {
643 		dquot_scan_active(sb, ocfs2_sync_dquot_helper, oinfo->dqi_type);
644 		up_read(&sb->s_umount);
645 	}
646 	schedule_delayed_work(&oinfo->dqi_sync_work,
647 			      msecs_to_jiffies(oinfo->dqi_syncms));
648 }
649 
650 /*
651  *  Wrappers for generic quota functions
652  */
653 
654 static int ocfs2_write_dquot(struct dquot *dquot)
655 {
656 	handle_t *handle;
657 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
658 	int status = 0;
659 
660 	trace_ocfs2_write_dquot(from_kqid(&init_user_ns, dquot->dq_id),
661 				dquot->dq_id.type);
662 
663 	handle = ocfs2_start_trans(osb, OCFS2_QWRITE_CREDITS);
664 	if (IS_ERR(handle)) {
665 		status = PTR_ERR(handle);
666 		mlog_errno(status);
667 		goto out;
668 	}
669 	mutex_lock(&sb_dqopt(dquot->dq_sb)->dqio_mutex);
670 	status = ocfs2_local_write_dquot(dquot);
671 	mutex_unlock(&sb_dqopt(dquot->dq_sb)->dqio_mutex);
672 	ocfs2_commit_trans(osb, handle);
673 out:
674 	return status;
675 }
676 
677 static int ocfs2_calc_qdel_credits(struct super_block *sb, int type)
678 {
679 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
680 	/*
681 	 * We modify tree, leaf block, global info, local chunk header,
682 	 * global and local inode; OCFS2_QINFO_WRITE_CREDITS already
683 	 * accounts for inode update
684 	 */
685 	return (oinfo->dqi_gi.dqi_qtree_depth + 2) *
686 	       OCFS2_QUOTA_BLOCK_UPDATE_CREDITS +
687 	       OCFS2_QINFO_WRITE_CREDITS +
688 	       OCFS2_INODE_UPDATE_CREDITS;
689 }
690 
691 void ocfs2_drop_dquot_refs(struct work_struct *work)
692 {
693 	struct ocfs2_super *osb = container_of(work, struct ocfs2_super,
694 					       dquot_drop_work);
695 	struct llist_node *list;
696 	struct ocfs2_dquot *odquot, *next_odquot;
697 
698 	list = llist_del_all(&osb->dquot_drop_list);
699 	llist_for_each_entry_safe(odquot, next_odquot, list, list) {
700 		/* Drop the reference we acquired in ocfs2_dquot_release() */
701 		dqput(&odquot->dq_dquot);
702 	}
703 }
704 
705 /*
706  * Called when the last reference to dquot is dropped. If we are called from
707  * downconvert thread, we cannot do all the handling here because grabbing
708  * quota lock could deadlock (the node holding the quota lock could need some
709  * other cluster lock to proceed but with blocked downconvert thread we cannot
710  * release any lock).
711  */
712 static int ocfs2_release_dquot(struct dquot *dquot)
713 {
714 	handle_t *handle;
715 	struct ocfs2_mem_dqinfo *oinfo =
716 			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
717 	struct ocfs2_super *osb = OCFS2_SB(dquot->dq_sb);
718 	int status = 0;
719 
720 	trace_ocfs2_release_dquot(from_kqid(&init_user_ns, dquot->dq_id),
721 				  dquot->dq_id.type);
722 
723 	mutex_lock(&dquot->dq_lock);
724 	/* Check whether we are not racing with some other dqget() */
725 	if (atomic_read(&dquot->dq_count) > 1)
726 		goto out;
727 	/* Running from downconvert thread? Postpone quota processing to wq */
728 	if (current == osb->dc_task) {
729 		/*
730 		 * Grab our own reference to dquot and queue it for delayed
731 		 * dropping.  Quota code rechecks after calling
732 		 * ->release_dquot() and won't free dquot structure.
733 		 */
734 		dqgrab(dquot);
735 		/* First entry on list -> queue work */
736 		if (llist_add(&OCFS2_DQUOT(dquot)->list, &osb->dquot_drop_list))
737 			queue_work(osb->ocfs2_wq, &osb->dquot_drop_work);
738 		goto out;
739 	}
740 	status = ocfs2_lock_global_qf(oinfo, 1);
741 	if (status < 0)
742 		goto out;
743 	handle = ocfs2_start_trans(osb,
744 		ocfs2_calc_qdel_credits(dquot->dq_sb, dquot->dq_id.type));
745 	if (IS_ERR(handle)) {
746 		status = PTR_ERR(handle);
747 		mlog_errno(status);
748 		goto out_ilock;
749 	}
750 
751 	status = ocfs2_global_release_dquot(dquot);
752 	if (status < 0) {
753 		mlog_errno(status);
754 		goto out_trans;
755 	}
756 	status = ocfs2_local_release_dquot(handle, dquot);
757 	/*
758 	 * If we fail here, we cannot do much as global structure is
759 	 * already released. So just complain...
760 	 */
761 	if (status < 0)
762 		mlog_errno(status);
763 	/*
764 	 * Clear dq_off so that we search for the structure in quota file next
765 	 * time we acquire it. The structure might be deleted and reallocated
766 	 * elsewhere by another node while our dquot structure is on freelist.
767 	 */
768 	dquot->dq_off = 0;
769 	clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
770 out_trans:
771 	ocfs2_commit_trans(osb, handle);
772 out_ilock:
773 	ocfs2_unlock_global_qf(oinfo, 1);
774 out:
775 	mutex_unlock(&dquot->dq_lock);
776 	if (status)
777 		mlog_errno(status);
778 	return status;
779 }
780 
781 /*
782  * Read global dquot structure from disk or create it if it does
783  * not exist. Also update use count of the global structure and
784  * create structure in node-local quota file.
785  */
786 static int ocfs2_acquire_dquot(struct dquot *dquot)
787 {
788 	int status = 0, err;
789 	int ex = 0;
790 	struct super_block *sb = dquot->dq_sb;
791 	struct ocfs2_super *osb = OCFS2_SB(sb);
792 	int type = dquot->dq_id.type;
793 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
794 	struct inode *gqinode = info->dqi_gqinode;
795 	int need_alloc = ocfs2_global_qinit_alloc(sb, type);
796 	handle_t *handle;
797 
798 	trace_ocfs2_acquire_dquot(from_kqid(&init_user_ns, dquot->dq_id),
799 				  type);
800 	mutex_lock(&dquot->dq_lock);
801 	/*
802 	 * We need an exclusive lock, because we're going to update use count
803 	 * and instantiate possibly new dquot structure
804 	 */
805 	status = ocfs2_lock_global_qf(info, 1);
806 	if (status < 0)
807 		goto out;
808 	status = ocfs2_qinfo_lock(info, 0);
809 	if (status < 0)
810 		goto out_dq;
811 	/*
812 	 * We always want to read dquot structure from disk because we don't
813 	 * know what happened with it while it was on freelist.
814 	 */
815 	status = qtree_read_dquot(&info->dqi_gi, dquot);
816 	ocfs2_qinfo_unlock(info, 0);
817 	if (status < 0)
818 		goto out_dq;
819 
820 	OCFS2_DQUOT(dquot)->dq_use_count++;
821 	OCFS2_DQUOT(dquot)->dq_origspace = dquot->dq_dqb.dqb_curspace;
822 	OCFS2_DQUOT(dquot)->dq_originodes = dquot->dq_dqb.dqb_curinodes;
823 	if (!dquot->dq_off) {	/* No real quota entry? */
824 		ex = 1;
825 		/*
826 		 * Add blocks to quota file before we start a transaction since
827 		 * locking allocators ranks above a transaction start
828 		 */
829 		WARN_ON(journal_current_handle());
830 		status = ocfs2_extend_no_holes(gqinode, NULL,
831 			i_size_read(gqinode) + (need_alloc << sb->s_blocksize_bits),
832 			i_size_read(gqinode));
833 		if (status < 0)
834 			goto out_dq;
835 	}
836 
837 	handle = ocfs2_start_trans(osb,
838 				   ocfs2_calc_global_qinit_credits(sb, type));
839 	if (IS_ERR(handle)) {
840 		status = PTR_ERR(handle);
841 		goto out_dq;
842 	}
843 	status = ocfs2_qinfo_lock(info, ex);
844 	if (status < 0)
845 		goto out_trans;
846 	status = qtree_write_dquot(&info->dqi_gi, dquot);
847 	if (ex && info_dirty(sb_dqinfo(sb, type))) {
848 		err = __ocfs2_global_write_info(sb, type);
849 		if (!status)
850 			status = err;
851 	}
852 	ocfs2_qinfo_unlock(info, ex);
853 out_trans:
854 	ocfs2_commit_trans(osb, handle);
855 out_dq:
856 	ocfs2_unlock_global_qf(info, 1);
857 	if (status < 0)
858 		goto out;
859 
860 	status = ocfs2_create_local_dquot(dquot);
861 	if (status < 0)
862 		goto out;
863 	set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
864 out:
865 	mutex_unlock(&dquot->dq_lock);
866 	if (status)
867 		mlog_errno(status);
868 	return status;
869 }
870 
871 static int ocfs2_get_next_id(struct super_block *sb, struct kqid *qid)
872 {
873 	int type = qid->type;
874 	struct ocfs2_mem_dqinfo *info = sb_dqinfo(sb, type)->dqi_priv;
875 	int status = 0;
876 
877 	trace_ocfs2_get_next_id(from_kqid(&init_user_ns, *qid), type);
878 	if (!sb_has_quota_loaded(sb, type)) {
879 		status = -ESRCH;
880 		goto out;
881 	}
882 	status = ocfs2_lock_global_qf(info, 0);
883 	if (status < 0)
884 		goto out;
885 	status = ocfs2_qinfo_lock(info, 0);
886 	if (status < 0)
887 		goto out_global;
888 	status = qtree_get_next_id(&info->dqi_gi, qid);
889 	ocfs2_qinfo_unlock(info, 0);
890 out_global:
891 	ocfs2_unlock_global_qf(info, 0);
892 out:
893 	/*
894 	 * Avoid logging ENOENT since it just means there isn't next ID and
895 	 * ESRCH which means quota isn't enabled for the filesystem.
896 	 */
897 	if (status && status != -ENOENT && status != -ESRCH)
898 		mlog_errno(status);
899 	return status;
900 }
901 
902 static int ocfs2_mark_dquot_dirty(struct dquot *dquot)
903 {
904 	unsigned long mask = (1 << (DQ_LASTSET_B + QIF_ILIMITS_B)) |
905 			     (1 << (DQ_LASTSET_B + QIF_BLIMITS_B)) |
906 			     (1 << (DQ_LASTSET_B + QIF_INODES_B)) |
907 			     (1 << (DQ_LASTSET_B + QIF_SPACE_B)) |
908 			     (1 << (DQ_LASTSET_B + QIF_BTIME_B)) |
909 			     (1 << (DQ_LASTSET_B + QIF_ITIME_B));
910 	int sync = 0;
911 	int status;
912 	struct super_block *sb = dquot->dq_sb;
913 	int type = dquot->dq_id.type;
914 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
915 	handle_t *handle;
916 	struct ocfs2_super *osb = OCFS2_SB(sb);
917 
918 	trace_ocfs2_mark_dquot_dirty(from_kqid(&init_user_ns, dquot->dq_id),
919 				     type);
920 
921 	/* In case user set some limits, sync dquot immediately to global
922 	 * quota file so that information propagates quicker */
923 	spin_lock(&dq_data_lock);
924 	if (dquot->dq_flags & mask)
925 		sync = 1;
926 	spin_unlock(&dq_data_lock);
927 	/* This is a slight hack but we can't afford getting global quota
928 	 * lock if we already have a transaction started. */
929 	if (!sync || journal_current_handle()) {
930 		status = ocfs2_write_dquot(dquot);
931 		goto out;
932 	}
933 	status = ocfs2_lock_global_qf(oinfo, 1);
934 	if (status < 0)
935 		goto out;
936 	handle = ocfs2_start_trans(osb, OCFS2_QSYNC_CREDITS);
937 	if (IS_ERR(handle)) {
938 		status = PTR_ERR(handle);
939 		mlog_errno(status);
940 		goto out_ilock;
941 	}
942 	mutex_lock(&sb_dqopt(sb)->dqio_mutex);
943 	status = ocfs2_sync_dquot(dquot);
944 	if (status < 0) {
945 		mlog_errno(status);
946 		goto out_dlock;
947 	}
948 	/* Now write updated local dquot structure */
949 	status = ocfs2_local_write_dquot(dquot);
950 out_dlock:
951 	mutex_unlock(&sb_dqopt(sb)->dqio_mutex);
952 	ocfs2_commit_trans(osb, handle);
953 out_ilock:
954 	ocfs2_unlock_global_qf(oinfo, 1);
955 out:
956 	if (status)
957 		mlog_errno(status);
958 	return status;
959 }
960 
961 /* This should happen only after set_dqinfo(). */
962 static int ocfs2_write_info(struct super_block *sb, int type)
963 {
964 	handle_t *handle;
965 	int status = 0;
966 	struct ocfs2_mem_dqinfo *oinfo = sb_dqinfo(sb, type)->dqi_priv;
967 
968 	status = ocfs2_lock_global_qf(oinfo, 1);
969 	if (status < 0)
970 		goto out;
971 	handle = ocfs2_start_trans(OCFS2_SB(sb), OCFS2_QINFO_WRITE_CREDITS);
972 	if (IS_ERR(handle)) {
973 		status = PTR_ERR(handle);
974 		mlog_errno(status);
975 		goto out_ilock;
976 	}
977 	status = dquot_commit_info(sb, type);
978 	ocfs2_commit_trans(OCFS2_SB(sb), handle);
979 out_ilock:
980 	ocfs2_unlock_global_qf(oinfo, 1);
981 out:
982 	if (status)
983 		mlog_errno(status);
984 	return status;
985 }
986 
987 static struct dquot *ocfs2_alloc_dquot(struct super_block *sb, int type)
988 {
989 	struct ocfs2_dquot *dquot =
990 				kmem_cache_zalloc(ocfs2_dquot_cachep, GFP_NOFS);
991 
992 	if (!dquot)
993 		return NULL;
994 	return &dquot->dq_dquot;
995 }
996 
997 static void ocfs2_destroy_dquot(struct dquot *dquot)
998 {
999 	kmem_cache_free(ocfs2_dquot_cachep, dquot);
1000 }
1001 
1002 const struct dquot_operations ocfs2_quota_operations = {
1003 	/* We never make dquot dirty so .write_dquot is never called */
1004 	.acquire_dquot	= ocfs2_acquire_dquot,
1005 	.release_dquot	= ocfs2_release_dquot,
1006 	.mark_dirty	= ocfs2_mark_dquot_dirty,
1007 	.write_info	= ocfs2_write_info,
1008 	.alloc_dquot	= ocfs2_alloc_dquot,
1009 	.destroy_dquot	= ocfs2_destroy_dquot,
1010 	.get_next_id	= ocfs2_get_next_id,
1011 };
1012