Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvar...
[pandora-kernel.git] / fs / xfs / quota / xfs_dquot_item.c
1 /*
2  * Copyright (c) 2000-2003 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_bit.h"
21 #include "xfs_log.h"
22 #include "xfs_inum.h"
23 #include "xfs_trans.h"
24 #include "xfs_sb.h"
25 #include "xfs_ag.h"
26 #include "xfs_dir2.h"
27 #include "xfs_alloc.h"
28 #include "xfs_dmapi.h"
29 #include "xfs_quota.h"
30 #include "xfs_mount.h"
31 #include "xfs_bmap_btree.h"
32 #include "xfs_alloc_btree.h"
33 #include "xfs_ialloc_btree.h"
34 #include "xfs_dir2_sf.h"
35 #include "xfs_attr_sf.h"
36 #include "xfs_dinode.h"
37 #include "xfs_inode.h"
38 #include "xfs_bmap.h"
39 #include "xfs_btree.h"
40 #include "xfs_ialloc.h"
41 #include "xfs_rtalloc.h"
42 #include "xfs_error.h"
43 #include "xfs_itable.h"
44 #include "xfs_rw.h"
45 #include "xfs_attr.h"
46 #include "xfs_buf_item.h"
47 #include "xfs_trans_priv.h"
48 #include "xfs_qm.h"
49
50 /*
51  * returns the number of iovecs needed to log the given dquot item.
52  */
53 /* ARGSUSED */
54 STATIC uint
55 xfs_qm_dquot_logitem_size(
56         xfs_dq_logitem_t        *logitem)
57 {
58         /*
59          * we need only two iovecs, one for the format, one for the real thing
60          */
61         return (2);
62 }
63
64 /*
65  * fills in the vector of log iovecs for the given dquot log item.
66  */
67 STATIC void
68 xfs_qm_dquot_logitem_format(
69         xfs_dq_logitem_t        *logitem,
70         xfs_log_iovec_t         *logvec)
71 {
72         ASSERT(logitem);
73         ASSERT(logitem->qli_dquot);
74
75         logvec->i_addr = (xfs_caddr_t)&logitem->qli_format;
76         logvec->i_len  = sizeof(xfs_dq_logformat_t);
77         logvec->i_type = XLOG_REG_TYPE_QFORMAT;
78         logvec++;
79         logvec->i_addr = (xfs_caddr_t)&logitem->qli_dquot->q_core;
80         logvec->i_len  = sizeof(xfs_disk_dquot_t);
81         logvec->i_type = XLOG_REG_TYPE_DQUOT;
82
83         ASSERT(2 == logitem->qli_item.li_desc->lid_size);
84         logitem->qli_format.qlf_size = 2;
85
86 }
87
88 /*
89  * Increment the pin count of the given dquot.
90  */
91 STATIC void
92 xfs_qm_dquot_logitem_pin(
93         xfs_dq_logitem_t *logitem)
94 {
95         xfs_dquot_t *dqp = logitem->qli_dquot;
96
97         ASSERT(XFS_DQ_IS_LOCKED(dqp));
98         atomic_inc(&dqp->q_pincount);
99 }
100
101 /*
102  * Decrement the pin count of the given dquot, and wake up
103  * anyone in xfs_dqwait_unpin() if the count goes to 0.  The
104  * dquot must have been previously pinned with a call to
105  * xfs_qm_dquot_logitem_pin().
106  */
107 /* ARGSUSED */
108 STATIC void
109 xfs_qm_dquot_logitem_unpin(
110         xfs_dq_logitem_t *logitem)
111 {
112         xfs_dquot_t *dqp = logitem->qli_dquot;
113
114         ASSERT(atomic_read(&dqp->q_pincount) > 0);
115         if (atomic_dec_and_test(&dqp->q_pincount))
116                 wake_up(&dqp->q_pinwait);
117 }
118
119 /* ARGSUSED */
120 STATIC void
121 xfs_qm_dquot_logitem_unpin_remove(
122         xfs_dq_logitem_t *logitem,
123         xfs_trans_t      *tp)
124 {
125         xfs_qm_dquot_logitem_unpin(logitem);
126 }
127
128 /*
129  * Given the logitem, this writes the corresponding dquot entry to disk
130  * asynchronously. This is called with the dquot entry securely locked;
131  * we simply get xfs_qm_dqflush() to do the work, and unlock the dquot
132  * at the end.
133  */
134 STATIC void
135 xfs_qm_dquot_logitem_push(
136         xfs_dq_logitem_t        *logitem)
137 {
138         xfs_dquot_t     *dqp;
139         int             error;
140
141         dqp = logitem->qli_dquot;
142
143         ASSERT(XFS_DQ_IS_LOCKED(dqp));
144         ASSERT(!completion_done(&dqp->q_flush));
145
146         /*
147          * Since we were able to lock the dquot's flush lock and
148          * we found it on the AIL, the dquot must be dirty.  This
149          * is because the dquot is removed from the AIL while still
150          * holding the flush lock in xfs_dqflush_done().  Thus, if
151          * we found it in the AIL and were able to obtain the flush
152          * lock without sleeping, then there must not have been
153          * anyone in the process of flushing the dquot.
154          */
155         error = xfs_qm_dqflush(dqp, 0);
156         if (error)
157                 xfs_fs_cmn_err(CE_WARN, dqp->q_mount,
158                         "xfs_qm_dquot_logitem_push: push error %d on dqp %p",
159                         error, dqp);
160         xfs_dqunlock(dqp);
161 }
162
163 /*ARGSUSED*/
164 STATIC xfs_lsn_t
165 xfs_qm_dquot_logitem_committed(
166         xfs_dq_logitem_t        *l,
167         xfs_lsn_t               lsn)
168 {
169         /*
170          * We always re-log the entire dquot when it becomes dirty,
171          * so, the latest copy _is_ the only one that matters.
172          */
173         return (lsn);
174 }
175
176
177 /*
178  * This is called to wait for the given dquot to be unpinned.
179  * Most of these pin/unpin routines are plagiarized from inode code.
180  */
181 void
182 xfs_qm_dqunpin_wait(
183         xfs_dquot_t     *dqp)
184 {
185         ASSERT(XFS_DQ_IS_LOCKED(dqp));
186         if (atomic_read(&dqp->q_pincount) == 0)
187                 return;
188
189         /*
190          * Give the log a push so we don't wait here too long.
191          */
192         xfs_log_force(dqp->q_mount, 0);
193         wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
194 }
195
196 /*
197  * This is called when IOP_TRYLOCK returns XFS_ITEM_PUSHBUF to indicate that
198  * the dquot is locked by us, but the flush lock isn't. So, here we are
199  * going to see if the relevant dquot buffer is incore, waiting on DELWRI.
200  * If so, we want to push it out to help us take this item off the AIL as soon
201  * as possible.
202  *
203  * We must not be holding the AIL lock at this point. Calling incore() to
204  * search the buffer cache can be a time consuming thing, and AIL lock is a
205  * spinlock.
206  */
207 STATIC void
208 xfs_qm_dquot_logitem_pushbuf(
209         xfs_dq_logitem_t    *qip)
210 {
211         xfs_dquot_t     *dqp;
212         xfs_mount_t     *mp;
213         xfs_buf_t       *bp;
214
215         dqp = qip->qli_dquot;
216         ASSERT(XFS_DQ_IS_LOCKED(dqp));
217
218         /*
219          * If flushlock isn't locked anymore, chances are that the
220          * inode flush completed and the inode was taken off the AIL.
221          * So, just get out.
222          */
223         if (completion_done(&dqp->q_flush)  ||
224             ((qip->qli_item.li_flags & XFS_LI_IN_AIL) == 0)) {
225                 xfs_dqunlock(dqp);
226                 return;
227         }
228         mp = dqp->q_mount;
229         bp = xfs_incore(mp->m_ddev_targp, qip->qli_format.qlf_blkno,
230                         mp->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK);
231         xfs_dqunlock(dqp);
232         if (!bp)
233                 return;
234         if (XFS_BUF_ISDELAYWRITE(bp))
235                 xfs_buf_delwri_promote(bp);
236         xfs_buf_relse(bp);
237         return;
238
239 }
240
241 /*
242  * This is called to attempt to lock the dquot associated with this
243  * dquot log item.  Don't sleep on the dquot lock or the flush lock.
244  * If the flush lock is already held, indicating that the dquot has
245  * been or is in the process of being flushed, then see if we can
246  * find the dquot's buffer in the buffer cache without sleeping.  If
247  * we can and it is marked delayed write, then we want to send it out.
248  * We delay doing so until the push routine, though, to avoid sleeping
249  * in any device strategy routines.
250  */
251 STATIC uint
252 xfs_qm_dquot_logitem_trylock(
253         xfs_dq_logitem_t        *qip)
254 {
255         xfs_dquot_t             *dqp;
256
257         dqp = qip->qli_dquot;
258         if (atomic_read(&dqp->q_pincount) > 0)
259                 return XFS_ITEM_PINNED;
260
261         if (! xfs_qm_dqlock_nowait(dqp))
262                 return XFS_ITEM_LOCKED;
263
264         if (!xfs_dqflock_nowait(dqp)) {
265                 /*
266                  * dquot has already been flushed to the backing buffer,
267                  * leave it locked, pushbuf routine will unlock it.
268                  */
269                 return XFS_ITEM_PUSHBUF;
270         }
271
272         ASSERT(qip->qli_item.li_flags & XFS_LI_IN_AIL);
273         return XFS_ITEM_SUCCESS;
274 }
275
276
277 /*
278  * Unlock the dquot associated with the log item.
279  * Clear the fields of the dquot and dquot log item that
280  * are specific to the current transaction.  If the
281  * hold flags is set, do not unlock the dquot.
282  */
283 STATIC void
284 xfs_qm_dquot_logitem_unlock(
285         xfs_dq_logitem_t    *ql)
286 {
287         xfs_dquot_t     *dqp;
288
289         ASSERT(ql != NULL);
290         dqp = ql->qli_dquot;
291         ASSERT(XFS_DQ_IS_LOCKED(dqp));
292
293         /*
294          * Clear the transaction pointer in the dquot
295          */
296         dqp->q_transp = NULL;
297
298         /*
299          * dquots are never 'held' from getting unlocked at the end of
300          * a transaction.  Their locking and unlocking is hidden inside the
301          * transaction layer, within trans_commit. Hence, no LI_HOLD flag
302          * for the logitem.
303          */
304         xfs_dqunlock(dqp);
305 }
306
307
308 /*
309  * this needs to stamp an lsn into the dquot, I think.
310  * rpc's that look at user dquot's would then have to
311  * push on the dependency recorded in the dquot
312  */
313 /* ARGSUSED */
314 STATIC void
315 xfs_qm_dquot_logitem_committing(
316         xfs_dq_logitem_t        *l,
317         xfs_lsn_t               lsn)
318 {
319         return;
320 }
321
322
323 /*
324  * This is the ops vector for dquots
325  */
326 static struct xfs_item_ops xfs_dquot_item_ops = {
327         .iop_size       = (uint(*)(xfs_log_item_t*))xfs_qm_dquot_logitem_size,
328         .iop_format     = (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
329                                         xfs_qm_dquot_logitem_format,
330         .iop_pin        = (void(*)(xfs_log_item_t*))xfs_qm_dquot_logitem_pin,
331         .iop_unpin      = (void(*)(xfs_log_item_t*))xfs_qm_dquot_logitem_unpin,
332         .iop_unpin_remove = (void(*)(xfs_log_item_t*, xfs_trans_t*))
333                                         xfs_qm_dquot_logitem_unpin_remove,
334         .iop_trylock    = (uint(*)(xfs_log_item_t*))
335                                         xfs_qm_dquot_logitem_trylock,
336         .iop_unlock     = (void(*)(xfs_log_item_t*))xfs_qm_dquot_logitem_unlock,
337         .iop_committed  = (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
338                                         xfs_qm_dquot_logitem_committed,
339         .iop_push       = (void(*)(xfs_log_item_t*))xfs_qm_dquot_logitem_push,
340         .iop_pushbuf    = (void(*)(xfs_log_item_t*))
341                                         xfs_qm_dquot_logitem_pushbuf,
342         .iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
343                                         xfs_qm_dquot_logitem_committing
344 };
345
346 /*
347  * Initialize the dquot log item for a newly allocated dquot.
348  * The dquot isn't locked at this point, but it isn't on any of the lists
349  * either, so we don't care.
350  */
351 void
352 xfs_qm_dquot_logitem_init(
353         struct xfs_dquot *dqp)
354 {
355         xfs_dq_logitem_t  *lp;
356         lp = &dqp->q_logitem;
357
358         xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
359                                         &xfs_dquot_item_ops);
360         lp->qli_dquot = dqp;
361         lp->qli_format.qlf_type = XFS_LI_DQUOT;
362         lp->qli_format.qlf_id = be32_to_cpu(dqp->q_core.d_id);
363         lp->qli_format.qlf_blkno = dqp->q_blkno;
364         lp->qli_format.qlf_len = 1;
365         /*
366          * This is just the offset of this dquot within its buffer
367          * (which is currently 1 FSB and probably won't change).
368          * Hence 32 bits for this offset should be just fine.
369          * Alternatively, we can store (bufoffset / sizeof(xfs_dqblk_t))
370          * here, and recompute it at recovery time.
371          */
372         lp->qli_format.qlf_boffset = (__uint32_t)dqp->q_bufoffset;
373 }
374
375 /*------------------  QUOTAOFF LOG ITEMS  -------------------*/
376
377 /*
378  * This returns the number of iovecs needed to log the given quotaoff item.
379  * We only need 1 iovec for an quotaoff item.  It just logs the
380  * quotaoff_log_format structure.
381  */
382 /*ARGSUSED*/
383 STATIC uint
384 xfs_qm_qoff_logitem_size(xfs_qoff_logitem_t *qf)
385 {
386         return (1);
387 }
388
389 /*
390  * This is called to fill in the vector of log iovecs for the
391  * given quotaoff log item. We use only 1 iovec, and we point that
392  * at the quotaoff_log_format structure embedded in the quotaoff item.
393  * It is at this point that we assert that all of the extent
394  * slots in the quotaoff item have been filled.
395  */
396 STATIC void
397 xfs_qm_qoff_logitem_format(xfs_qoff_logitem_t   *qf,
398                            xfs_log_iovec_t      *log_vector)
399 {
400         ASSERT(qf->qql_format.qf_type == XFS_LI_QUOTAOFF);
401
402         log_vector->i_addr = (xfs_caddr_t)&(qf->qql_format);
403         log_vector->i_len = sizeof(xfs_qoff_logitem_t);
404         log_vector->i_type = XLOG_REG_TYPE_QUOTAOFF;
405         qf->qql_format.qf_size = 1;
406 }
407
408
409 /*
410  * Pinning has no meaning for an quotaoff item, so just return.
411  */
412 /*ARGSUSED*/
413 STATIC void
414 xfs_qm_qoff_logitem_pin(xfs_qoff_logitem_t *qf)
415 {
416         return;
417 }
418
419
420 /*
421  * Since pinning has no meaning for an quotaoff item, unpinning does
422  * not either.
423  */
424 /*ARGSUSED*/
425 STATIC void
426 xfs_qm_qoff_logitem_unpin(xfs_qoff_logitem_t *qf)
427 {
428         return;
429 }
430
431 /*ARGSUSED*/
432 STATIC void
433 xfs_qm_qoff_logitem_unpin_remove(xfs_qoff_logitem_t *qf, xfs_trans_t *tp)
434 {
435         return;
436 }
437
438 /*
439  * Quotaoff items have no locking, so just return success.
440  */
441 /*ARGSUSED*/
442 STATIC uint
443 xfs_qm_qoff_logitem_trylock(xfs_qoff_logitem_t *qf)
444 {
445         return XFS_ITEM_LOCKED;
446 }
447
448 /*
449  * Quotaoff items have no locking or pushing, so return failure
450  * so that the caller doesn't bother with us.
451  */
452 /*ARGSUSED*/
453 STATIC void
454 xfs_qm_qoff_logitem_unlock(xfs_qoff_logitem_t *qf)
455 {
456         return;
457 }
458
459 /*
460  * The quotaoff-start-item is logged only once and cannot be moved in the log,
461  * so simply return the lsn at which it's been logged.
462  */
463 /*ARGSUSED*/
464 STATIC xfs_lsn_t
465 xfs_qm_qoff_logitem_committed(xfs_qoff_logitem_t *qf, xfs_lsn_t lsn)
466 {
467         return (lsn);
468 }
469
470 /*
471  * There isn't much you can do to push on an quotaoff item.  It is simply
472  * stuck waiting for the log to be flushed to disk.
473  */
474 /*ARGSUSED*/
475 STATIC void
476 xfs_qm_qoff_logitem_push(xfs_qoff_logitem_t *qf)
477 {
478         return;
479 }
480
481
482 /*ARGSUSED*/
483 STATIC xfs_lsn_t
484 xfs_qm_qoffend_logitem_committed(
485         xfs_qoff_logitem_t *qfe,
486         xfs_lsn_t lsn)
487 {
488         xfs_qoff_logitem_t      *qfs;
489         struct xfs_ail          *ailp;
490
491         qfs = qfe->qql_start_lip;
492         ailp = qfs->qql_item.li_ailp;
493         spin_lock(&ailp->xa_lock);
494         /*
495          * Delete the qoff-start logitem from the AIL.
496          * xfs_trans_ail_delete() drops the AIL lock.
497          */
498         xfs_trans_ail_delete(ailp, (xfs_log_item_t *)qfs);
499         kmem_free(qfs);
500         kmem_free(qfe);
501         return (xfs_lsn_t)-1;
502 }
503
504 /*
505  * XXX rcc - don't know quite what to do with this.  I think we can
506  * just ignore it.  The only time that isn't the case is if we allow
507  * the client to somehow see that quotas have been turned off in which
508  * we can't allow that to get back until the quotaoff hits the disk.
509  * So how would that happen?  Also, do we need different routines for
510  * quotaoff start and quotaoff end?  I suspect the answer is yes but
511  * to be sure, I need to look at the recovery code and see how quota off
512  * recovery is handled (do we roll forward or back or do something else).
513  * If we roll forwards or backwards, then we need two separate routines,
514  * one that does nothing and one that stamps in the lsn that matters
515  * (truly makes the quotaoff irrevocable).  If we do something else,
516  * then maybe we don't need two.
517  */
518 /* ARGSUSED */
519 STATIC void
520 xfs_qm_qoff_logitem_committing(xfs_qoff_logitem_t *qip, xfs_lsn_t commit_lsn)
521 {
522         return;
523 }
524
525 /* ARGSUSED */
526 STATIC void
527 xfs_qm_qoffend_logitem_committing(xfs_qoff_logitem_t *qip, xfs_lsn_t commit_lsn)
528 {
529         return;
530 }
531
532 static struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
533         .iop_size       = (uint(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_size,
534         .iop_format     = (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
535                                         xfs_qm_qoff_logitem_format,
536         .iop_pin        = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_pin,
537         .iop_unpin      = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_unpin,
538         .iop_unpin_remove = (void(*)(xfs_log_item_t*,xfs_trans_t*))
539                                         xfs_qm_qoff_logitem_unpin_remove,
540         .iop_trylock    = (uint(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_trylock,
541         .iop_unlock     = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_unlock,
542         .iop_committed  = (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
543                                         xfs_qm_qoffend_logitem_committed,
544         .iop_push       = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_push,
545         .iop_pushbuf    = NULL,
546         .iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
547                                         xfs_qm_qoffend_logitem_committing
548 };
549
550 /*
551  * This is the ops vector shared by all quotaoff-start log items.
552  */
553 static struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
554         .iop_size       = (uint(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_size,
555         .iop_format     = (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
556                                         xfs_qm_qoff_logitem_format,
557         .iop_pin        = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_pin,
558         .iop_unpin      = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_unpin,
559         .iop_unpin_remove = (void(*)(xfs_log_item_t*,xfs_trans_t*))
560                                         xfs_qm_qoff_logitem_unpin_remove,
561         .iop_trylock    = (uint(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_trylock,
562         .iop_unlock     = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_unlock,
563         .iop_committed  = (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
564                                         xfs_qm_qoff_logitem_committed,
565         .iop_push       = (void(*)(xfs_log_item_t*))xfs_qm_qoff_logitem_push,
566         .iop_pushbuf    = NULL,
567         .iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
568                                         xfs_qm_qoff_logitem_committing
569 };
570
571 /*
572  * Allocate and initialize an quotaoff item of the correct quota type(s).
573  */
574 xfs_qoff_logitem_t *
575 xfs_qm_qoff_logitem_init(
576         struct xfs_mount *mp,
577         xfs_qoff_logitem_t *start,
578         uint flags)
579 {
580         xfs_qoff_logitem_t      *qf;
581
582         qf = (xfs_qoff_logitem_t*) kmem_zalloc(sizeof(xfs_qoff_logitem_t), KM_SLEEP);
583
584         xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
585                         &xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
586         qf->qql_item.li_mountp = mp;
587         qf->qql_format.qf_type = XFS_LI_QUOTAOFF;
588         qf->qql_format.qf_flags = flags;
589         qf->qql_start_lip = start;
590         return (qf);
591 }