gspca: Fix falling back to lower isoc alt settings
[zen-stable.git] / fs / xfs / xfs_dquot_item.c
blob0dee0b71029d8406add271b9f20350e6b8a97859
1 /*
2 * Copyright (c) 2000-2003 Silicon Graphics, Inc.
3 * All Rights Reserved.
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.
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.
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
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_alloc.h"
27 #include "xfs_quota.h"
28 #include "xfs_mount.h"
29 #include "xfs_bmap_btree.h"
30 #include "xfs_inode.h"
31 #include "xfs_bmap.h"
32 #include "xfs_rtalloc.h"
33 #include "xfs_error.h"
34 #include "xfs_itable.h"
35 #include "xfs_attr.h"
36 #include "xfs_buf_item.h"
37 #include "xfs_trans_priv.h"
38 #include "xfs_qm.h"
40 static inline struct xfs_dq_logitem *DQUOT_ITEM(struct xfs_log_item *lip)
42 return container_of(lip, struct xfs_dq_logitem, qli_item);
46 * returns the number of iovecs needed to log the given dquot item.
48 STATIC uint
49 xfs_qm_dquot_logitem_size(
50 struct xfs_log_item *lip)
53 * we need only two iovecs, one for the format, one for the real thing
55 return 2;
59 * fills in the vector of log iovecs for the given dquot log item.
61 STATIC void
62 xfs_qm_dquot_logitem_format(
63 struct xfs_log_item *lip,
64 struct xfs_log_iovec *logvec)
66 struct xfs_dq_logitem *qlip = DQUOT_ITEM(lip);
68 logvec->i_addr = &qlip->qli_format;
69 logvec->i_len = sizeof(xfs_dq_logformat_t);
70 logvec->i_type = XLOG_REG_TYPE_QFORMAT;
71 logvec++;
72 logvec->i_addr = &qlip->qli_dquot->q_core;
73 logvec->i_len = sizeof(xfs_disk_dquot_t);
74 logvec->i_type = XLOG_REG_TYPE_DQUOT;
76 ASSERT(2 == lip->li_desc->lid_size);
77 qlip->qli_format.qlf_size = 2;
82 * Increment the pin count of the given dquot.
84 STATIC void
85 xfs_qm_dquot_logitem_pin(
86 struct xfs_log_item *lip)
88 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
90 ASSERT(XFS_DQ_IS_LOCKED(dqp));
91 atomic_inc(&dqp->q_pincount);
95 * Decrement the pin count of the given dquot, and wake up
96 * anyone in xfs_dqwait_unpin() if the count goes to 0. The
97 * dquot must have been previously pinned with a call to
98 * xfs_qm_dquot_logitem_pin().
100 STATIC void
101 xfs_qm_dquot_logitem_unpin(
102 struct xfs_log_item *lip,
103 int remove)
105 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
107 ASSERT(atomic_read(&dqp->q_pincount) > 0);
108 if (atomic_dec_and_test(&dqp->q_pincount))
109 wake_up(&dqp->q_pinwait);
113 * Given the logitem, this writes the corresponding dquot entry to disk
114 * asynchronously. This is called with the dquot entry securely locked;
115 * we simply get xfs_qm_dqflush() to do the work, and unlock the dquot
116 * at the end.
118 STATIC void
119 xfs_qm_dquot_logitem_push(
120 struct xfs_log_item *lip)
122 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
123 int error;
125 ASSERT(XFS_DQ_IS_LOCKED(dqp));
126 ASSERT(!completion_done(&dqp->q_flush));
129 * Since we were able to lock the dquot's flush lock and
130 * we found it on the AIL, the dquot must be dirty. This
131 * is because the dquot is removed from the AIL while still
132 * holding the flush lock in xfs_dqflush_done(). Thus, if
133 * we found it in the AIL and were able to obtain the flush
134 * lock without sleeping, then there must not have been
135 * anyone in the process of flushing the dquot.
137 error = xfs_qm_dqflush(dqp, 0);
138 if (error)
139 xfs_warn(dqp->q_mount, "%s: push error %d on dqp %p",
140 __func__, error, dqp);
141 xfs_dqunlock(dqp);
144 STATIC xfs_lsn_t
145 xfs_qm_dquot_logitem_committed(
146 struct xfs_log_item *lip,
147 xfs_lsn_t lsn)
150 * We always re-log the entire dquot when it becomes dirty,
151 * so, the latest copy _is_ the only one that matters.
153 return lsn;
157 * This is called to wait for the given dquot to be unpinned.
158 * Most of these pin/unpin routines are plagiarized from inode code.
160 void
161 xfs_qm_dqunpin_wait(
162 struct xfs_dquot *dqp)
164 ASSERT(XFS_DQ_IS_LOCKED(dqp));
165 if (atomic_read(&dqp->q_pincount) == 0)
166 return;
169 * Give the log a push so we don't wait here too long.
171 xfs_log_force(dqp->q_mount, 0);
172 wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
176 * This is called when IOP_TRYLOCK returns XFS_ITEM_PUSHBUF to indicate that
177 * the dquot is locked by us, but the flush lock isn't. So, here we are
178 * going to see if the relevant dquot buffer is incore, waiting on DELWRI.
179 * If so, we want to push it out to help us take this item off the AIL as soon
180 * as possible.
182 * We must not be holding the AIL lock at this point. Calling incore() to
183 * search the buffer cache can be a time consuming thing, and AIL lock is a
184 * spinlock.
186 STATIC bool
187 xfs_qm_dquot_logitem_pushbuf(
188 struct xfs_log_item *lip)
190 struct xfs_dq_logitem *qlip = DQUOT_ITEM(lip);
191 struct xfs_dquot *dqp = qlip->qli_dquot;
192 struct xfs_buf *bp;
193 bool ret = true;
195 ASSERT(XFS_DQ_IS_LOCKED(dqp));
198 * If flushlock isn't locked anymore, chances are that the
199 * inode flush completed and the inode was taken off the AIL.
200 * So, just get out.
202 if (completion_done(&dqp->q_flush) ||
203 !(lip->li_flags & XFS_LI_IN_AIL)) {
204 xfs_dqunlock(dqp);
205 return true;
208 bp = xfs_incore(dqp->q_mount->m_ddev_targp, qlip->qli_format.qlf_blkno,
209 dqp->q_mount->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK);
210 xfs_dqunlock(dqp);
211 if (!bp)
212 return true;
213 if (XFS_BUF_ISDELAYWRITE(bp))
214 xfs_buf_delwri_promote(bp);
215 if (xfs_buf_ispinned(bp))
216 ret = false;
217 xfs_buf_relse(bp);
218 return ret;
222 * This is called to attempt to lock the dquot associated with this
223 * dquot log item. Don't sleep on the dquot lock or the flush lock.
224 * If the flush lock is already held, indicating that the dquot has
225 * been or is in the process of being flushed, then see if we can
226 * find the dquot's buffer in the buffer cache without sleeping. If
227 * we can and it is marked delayed write, then we want to send it out.
228 * We delay doing so until the push routine, though, to avoid sleeping
229 * in any device strategy routines.
231 STATIC uint
232 xfs_qm_dquot_logitem_trylock(
233 struct xfs_log_item *lip)
235 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
237 if (atomic_read(&dqp->q_pincount) > 0)
238 return XFS_ITEM_PINNED;
240 if (!xfs_qm_dqlock_nowait(dqp))
241 return XFS_ITEM_LOCKED;
243 if (!xfs_dqflock_nowait(dqp)) {
245 * dquot has already been flushed to the backing buffer,
246 * leave it locked, pushbuf routine will unlock it.
248 return XFS_ITEM_PUSHBUF;
251 ASSERT(lip->li_flags & XFS_LI_IN_AIL);
252 return XFS_ITEM_SUCCESS;
256 * Unlock the dquot associated with the log item.
257 * Clear the fields of the dquot and dquot log item that
258 * are specific to the current transaction. If the
259 * hold flags is set, do not unlock the dquot.
261 STATIC void
262 xfs_qm_dquot_logitem_unlock(
263 struct xfs_log_item *lip)
265 struct xfs_dquot *dqp = DQUOT_ITEM(lip)->qli_dquot;
267 ASSERT(XFS_DQ_IS_LOCKED(dqp));
270 * Clear the transaction pointer in the dquot
272 dqp->q_transp = NULL;
275 * dquots are never 'held' from getting unlocked at the end of
276 * a transaction. Their locking and unlocking is hidden inside the
277 * transaction layer, within trans_commit. Hence, no LI_HOLD flag
278 * for the logitem.
280 xfs_dqunlock(dqp);
284 * this needs to stamp an lsn into the dquot, I think.
285 * rpc's that look at user dquot's would then have to
286 * push on the dependency recorded in the dquot
288 STATIC void
289 xfs_qm_dquot_logitem_committing(
290 struct xfs_log_item *lip,
291 xfs_lsn_t lsn)
296 * This is the ops vector for dquots
298 static const struct xfs_item_ops xfs_dquot_item_ops = {
299 .iop_size = xfs_qm_dquot_logitem_size,
300 .iop_format = xfs_qm_dquot_logitem_format,
301 .iop_pin = xfs_qm_dquot_logitem_pin,
302 .iop_unpin = xfs_qm_dquot_logitem_unpin,
303 .iop_trylock = xfs_qm_dquot_logitem_trylock,
304 .iop_unlock = xfs_qm_dquot_logitem_unlock,
305 .iop_committed = xfs_qm_dquot_logitem_committed,
306 .iop_push = xfs_qm_dquot_logitem_push,
307 .iop_pushbuf = xfs_qm_dquot_logitem_pushbuf,
308 .iop_committing = xfs_qm_dquot_logitem_committing
312 * Initialize the dquot log item for a newly allocated dquot.
313 * The dquot isn't locked at this point, but it isn't on any of the lists
314 * either, so we don't care.
316 void
317 xfs_qm_dquot_logitem_init(
318 struct xfs_dquot *dqp)
320 struct xfs_dq_logitem *lp = &dqp->q_logitem;
322 xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
323 &xfs_dquot_item_ops);
324 lp->qli_dquot = dqp;
325 lp->qli_format.qlf_type = XFS_LI_DQUOT;
326 lp->qli_format.qlf_id = be32_to_cpu(dqp->q_core.d_id);
327 lp->qli_format.qlf_blkno = dqp->q_blkno;
328 lp->qli_format.qlf_len = 1;
330 * This is just the offset of this dquot within its buffer
331 * (which is currently 1 FSB and probably won't change).
332 * Hence 32 bits for this offset should be just fine.
333 * Alternatively, we can store (bufoffset / sizeof(xfs_dqblk_t))
334 * here, and recompute it at recovery time.
336 lp->qli_format.qlf_boffset = (__uint32_t)dqp->q_bufoffset;
339 /*------------------ QUOTAOFF LOG ITEMS -------------------*/
341 static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
343 return container_of(lip, struct xfs_qoff_logitem, qql_item);
348 * This returns the number of iovecs needed to log the given quotaoff item.
349 * We only need 1 iovec for an quotaoff item. It just logs the
350 * quotaoff_log_format structure.
352 STATIC uint
353 xfs_qm_qoff_logitem_size(
354 struct xfs_log_item *lip)
356 return 1;
360 * This is called to fill in the vector of log iovecs for the
361 * given quotaoff log item. We use only 1 iovec, and we point that
362 * at the quotaoff_log_format structure embedded in the quotaoff item.
363 * It is at this point that we assert that all of the extent
364 * slots in the quotaoff item have been filled.
366 STATIC void
367 xfs_qm_qoff_logitem_format(
368 struct xfs_log_item *lip,
369 struct xfs_log_iovec *log_vector)
371 struct xfs_qoff_logitem *qflip = QOFF_ITEM(lip);
373 ASSERT(qflip->qql_format.qf_type == XFS_LI_QUOTAOFF);
375 log_vector->i_addr = &qflip->qql_format;
376 log_vector->i_len = sizeof(xfs_qoff_logitem_t);
377 log_vector->i_type = XLOG_REG_TYPE_QUOTAOFF;
378 qflip->qql_format.qf_size = 1;
382 * Pinning has no meaning for an quotaoff item, so just return.
384 STATIC void
385 xfs_qm_qoff_logitem_pin(
386 struct xfs_log_item *lip)
391 * Since pinning has no meaning for an quotaoff item, unpinning does
392 * not either.
394 STATIC void
395 xfs_qm_qoff_logitem_unpin(
396 struct xfs_log_item *lip,
397 int remove)
402 * Quotaoff items have no locking, so just return success.
404 STATIC uint
405 xfs_qm_qoff_logitem_trylock(
406 struct xfs_log_item *lip)
408 return XFS_ITEM_LOCKED;
412 * Quotaoff items have no locking or pushing, so return failure
413 * so that the caller doesn't bother with us.
415 STATIC void
416 xfs_qm_qoff_logitem_unlock(
417 struct xfs_log_item *lip)
422 * The quotaoff-start-item is logged only once and cannot be moved in the log,
423 * so simply return the lsn at which it's been logged.
425 STATIC xfs_lsn_t
426 xfs_qm_qoff_logitem_committed(
427 struct xfs_log_item *lip,
428 xfs_lsn_t lsn)
430 return lsn;
434 * There isn't much you can do to push on an quotaoff item. It is simply
435 * stuck waiting for the log to be flushed to disk.
437 STATIC void
438 xfs_qm_qoff_logitem_push(
439 struct xfs_log_item *lip)
444 STATIC xfs_lsn_t
445 xfs_qm_qoffend_logitem_committed(
446 struct xfs_log_item *lip,
447 xfs_lsn_t lsn)
449 struct xfs_qoff_logitem *qfe = QOFF_ITEM(lip);
450 struct xfs_qoff_logitem *qfs = qfe->qql_start_lip;
451 struct xfs_ail *ailp = qfs->qql_item.li_ailp;
454 * Delete the qoff-start logitem from the AIL.
455 * xfs_trans_ail_delete() drops the AIL lock.
457 spin_lock(&ailp->xa_lock);
458 xfs_trans_ail_delete(ailp, (xfs_log_item_t *)qfs);
460 kmem_free(qfs);
461 kmem_free(qfe);
462 return (xfs_lsn_t)-1;
466 * XXX rcc - don't know quite what to do with this. I think we can
467 * just ignore it. The only time that isn't the case is if we allow
468 * the client to somehow see that quotas have been turned off in which
469 * we can't allow that to get back until the quotaoff hits the disk.
470 * So how would that happen? Also, do we need different routines for
471 * quotaoff start and quotaoff end? I suspect the answer is yes but
472 * to be sure, I need to look at the recovery code and see how quota off
473 * recovery is handled (do we roll forward or back or do something else).
474 * If we roll forwards or backwards, then we need two separate routines,
475 * one that does nothing and one that stamps in the lsn that matters
476 * (truly makes the quotaoff irrevocable). If we do something else,
477 * then maybe we don't need two.
479 STATIC void
480 xfs_qm_qoff_logitem_committing(
481 struct xfs_log_item *lip,
482 xfs_lsn_t commit_lsn)
486 static const struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
487 .iop_size = xfs_qm_qoff_logitem_size,
488 .iop_format = xfs_qm_qoff_logitem_format,
489 .iop_pin = xfs_qm_qoff_logitem_pin,
490 .iop_unpin = xfs_qm_qoff_logitem_unpin,
491 .iop_trylock = xfs_qm_qoff_logitem_trylock,
492 .iop_unlock = xfs_qm_qoff_logitem_unlock,
493 .iop_committed = xfs_qm_qoffend_logitem_committed,
494 .iop_push = xfs_qm_qoff_logitem_push,
495 .iop_committing = xfs_qm_qoff_logitem_committing
499 * This is the ops vector shared by all quotaoff-start log items.
501 static const struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
502 .iop_size = xfs_qm_qoff_logitem_size,
503 .iop_format = xfs_qm_qoff_logitem_format,
504 .iop_pin = xfs_qm_qoff_logitem_pin,
505 .iop_unpin = xfs_qm_qoff_logitem_unpin,
506 .iop_trylock = xfs_qm_qoff_logitem_trylock,
507 .iop_unlock = xfs_qm_qoff_logitem_unlock,
508 .iop_committed = xfs_qm_qoff_logitem_committed,
509 .iop_push = xfs_qm_qoff_logitem_push,
510 .iop_committing = xfs_qm_qoff_logitem_committing
514 * Allocate and initialize an quotaoff item of the correct quota type(s).
516 struct xfs_qoff_logitem *
517 xfs_qm_qoff_logitem_init(
518 struct xfs_mount *mp,
519 struct xfs_qoff_logitem *start,
520 uint flags)
522 struct xfs_qoff_logitem *qf;
524 qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
526 xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
527 &xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
528 qf->qql_item.li_mountp = mp;
529 qf->qql_format.qf_type = XFS_LI_QUOTAOFF;
530 qf->qql_format.qf_flags = flags;
531 qf->qql_start_lip = start;
532 return qf;