kernel/fs/xfs/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_format.h"
  21 #include "xfs_log_format.h"
  22 #include "xfs_trans_resv.h"
  23 #include "xfs_mount.h"
  24 #include "xfs_inode.h"
  25 #include "xfs_quota.h"
  26 #include "xfs_error.h"
  27 #include "xfs_trans.h"
  28 #include "xfs_buf_item.h"
  29 #include "xfs_trans_priv.h"
  30 #include "xfs_qm.h"
  31 #include "xfs_log.h"
  32
  33 static inline struct xfs_dq_logitem *DQUOT_ITEM(struct xfs_log_item *lip)
  34 {
  35         return container_of(lip, struct xfs_dq_logitem, qli_item);
  36 }
  37
  38 /*
  39  * returns the number of iovecs needed to log the given dquot item.
  40  */
  41 STATIC void
  42 xfs_qm_dquot_logitem_size(
  43         struct xfs_log_item     *lip,
  44         int                     *nvecs,
  45         int                     *nbytes)
  46 {
  47         *nvecs += 2;
  48         *nbytes += sizeof(struct xfs_dq_logformat) +
  49                    sizeof(struct xfs_disk_dquot);
  50 }
  51
  52 /*
  53  * fills in the vector of log iovecs for the given dquot log item.
  54  */
  55 STATIC void
  56 xfs_qm_dquot_logitem_format(
  57         struct xfs_log_item     *lip,
  58         struct xfs_log_vec      *lv)
  59 {
  60         struct xfs_dq_logitem   *qlip = DQUOT_ITEM(lip);
  61         struct xfs_log_iovec    *vecp = NULL;
  62         struct xfs_dq_logformat *qlf;
  63
  64         qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QFORMAT);
  65         qlf->qlf_type = XFS_LI_DQUOT;
  66         qlf->qlf_size = 2;
  67         qlf->qlf_id = be32_to_cpu(qlip->qli_dquot->q_core.d_id);
  68         qlf->qlf_blkno = qlip->qli_dquot->q_blkno;
  69         qlf->qlf_len = 1;
  70         qlf->qlf_boffset = qlip->qli_dquot->q_bufoffset;
  71         xlog_finish_iovec(lv, vecp, sizeof(struct xfs_dq_logformat));
  72
  73         xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_DQUOT,
  74                         &qlip->qli_dquot->q_core,
  75                         sizeof(struct xfs_disk_dquot));
  76 }
  77
  78 /*
  79  * Increment the pin count of the given dquot.
  80  */
  81 STATIC void
  82 xfs_qm_dquot_logitem_pin(
  83         struct xfs_log_item     *lip)
  84 {
  85         struct xfs_dquot        *dqp = DQUOT_ITEM(lip)->qli_dquot;
  86
  87         ASSERT(XFS_DQ_IS_LOCKED(dqp));
  88         atomic_inc(&dqp->q_pincount);
  89 }
  90
  91 /*
  92  * Decrement the pin count of the given dquot, and wake up
  93  * anyone in xfs_dqwait_unpin() if the count goes to 0.  The
  94  * dquot must have been previously pinned with a call to
  95  * xfs_qm_dquot_logitem_pin().
  96  */
  97 STATIC void
  98 xfs_qm_dquot_logitem_unpin(
  99         struct xfs_log_item     *lip,
 100         int                     remove)
 101 {
 102         struct xfs_dquot        *dqp = DQUOT_ITEM(lip)->qli_dquot;
 103
 104         ASSERT(atomic_read(&dqp->q_pincount) > 0);
 105         if (atomic_dec_and_test(&dqp->q_pincount))
 106                 wake_up(&dqp->q_pinwait);
 107 }
 108
 109 STATIC xfs_lsn_t
 110 xfs_qm_dquot_logitem_committed(
 111         struct xfs_log_item     *lip,
 112         xfs_lsn_t               lsn)
 113 {
 114         /*
 115          * We always re-log the entire dquot when it becomes dirty,
 116          * so, the latest copy _is_ the only one that matters.
 117          */
 118         return lsn;
 119 }
 120
 121 /*
 122  * This is called to wait for the given dquot to be unpinned.
 123  * Most of these pin/unpin routines are plagiarized from inode code.
 124  */
 125 void
 126 xfs_qm_dqunpin_wait(
 127         struct xfs_dquot        *dqp)
 128 {
 129         ASSERT(XFS_DQ_IS_LOCKED(dqp));
 130         if (atomic_read(&dqp->q_pincount) == 0)
 131                 return;
 132
 133         /*
 134          * Give the log a push so we don't wait here too long.
 135          */
 136         xfs_log_force(dqp->q_mount, 0);
 137         wait_event(dqp->q_pinwait, (atomic_read(&dqp->q_pincount) == 0));
 138 }
 139
 140 STATIC uint
 141 xfs_qm_dquot_logitem_push(
 142         struct xfs_log_item     *lip,
 143         struct list_head        *buffer_list) __releases(&lip->li_ailp->xa_lock)
 144                                               __acquires(&lip->li_ailp->xa_lock)
 145 {
 146         struct xfs_dquot        *dqp = DQUOT_ITEM(lip)->qli_dquot;
 147         struct xfs_buf          *bp = NULL;
 148         uint                    rval = XFS_ITEM_SUCCESS;
 149         int                     error;
 150
 151         if (atomic_read(&dqp->q_pincount) > 0)
 152                 return XFS_ITEM_PINNED;
 153
 154         if (!xfs_dqlock_nowait(dqp))
 155                 return XFS_ITEM_LOCKED;
 156
 157         /*
 158          * Re-check the pincount now that we stabilized the value by
 159          * taking the quota lock.
 160          */
 161         if (atomic_read(&dqp->q_pincount) > 0) {
 162                 rval = XFS_ITEM_PINNED;
 163                 goto out_unlock;
 164         }
 165
 166         /*
 167          * Someone else is already flushing the dquot.  Nothing we can do
 168          * here but wait for the flush to finish and remove the item from
 169          * the AIL.
 170          */
 171         if (!xfs_dqflock_nowait(dqp)) {
 172                 rval = XFS_ITEM_FLUSHING;
 173                 goto out_unlock;
 174         }
 175
 176         spin_unlock(&lip->li_ailp->xa_lock);
 177
 178         error = xfs_qm_dqflush(dqp, &bp);
 179         if (error) {
 180                 xfs_warn(dqp->q_mount, "%s: push error %d on dqp %p",
 181                         __func__, error, dqp);
 182         } else {
 183                 if (!xfs_buf_delwri_queue(bp, buffer_list))
 184                         rval = XFS_ITEM_FLUSHING;
 185                 xfs_buf_relse(bp);
 186         }
 187
 188         spin_lock(&lip->li_ailp->xa_lock);
 189 out_unlock:
 190         xfs_dqunlock(dqp);
 191         return rval;
 192 }
 193
 194 /*
 195  * Unlock the dquot associated with the log item.
 196  * Clear the fields of the dquot and dquot log item that
 197  * are specific to the current transaction.  If the
 198  * hold flags is set, do not unlock the dquot.
 199  */
 200 STATIC void
 201 xfs_qm_dquot_logitem_unlock(
 202         struct xfs_log_item     *lip)
 203 {
 204         struct xfs_dquot        *dqp = DQUOT_ITEM(lip)->qli_dquot;
 205
 206         ASSERT(XFS_DQ_IS_LOCKED(dqp));
 207
 208         /*
 209          * Clear the transaction pointer in the dquot
 210          */
 211         dqp->q_transp = NULL;
 212
 213         /*
 214          * dquots are never 'held' from getting unlocked at the end of
 215          * a transaction.  Their locking and unlocking is hidden inside the
 216          * transaction layer, within trans_commit. Hence, no LI_HOLD flag
 217          * for the logitem.
 218          */
 219         xfs_dqunlock(dqp);
 220 }
 221
 222 /*
 223  * this needs to stamp an lsn into the dquot, I think.
 224  * rpc's that look at user dquot's would then have to
 225  * push on the dependency recorded in the dquot
 226  */
 227 STATIC void
 228 xfs_qm_dquot_logitem_committing(
 229         struct xfs_log_item     *lip,
 230         xfs_lsn_t               lsn)
 231 {
 232 }
 233
 234 /*
 235  * This is the ops vector for dquots
 236  */
 237 static const struct xfs_item_ops xfs_dquot_item_ops = {
 238         .iop_size       = xfs_qm_dquot_logitem_size,
 239         .iop_format     = xfs_qm_dquot_logitem_format,
 240         .iop_pin        = xfs_qm_dquot_logitem_pin,
 241         .iop_unpin      = xfs_qm_dquot_logitem_unpin,
 242         .iop_unlock     = xfs_qm_dquot_logitem_unlock,
 243         .iop_committed  = xfs_qm_dquot_logitem_committed,
 244         .iop_push       = xfs_qm_dquot_logitem_push,
 245         .iop_committing = xfs_qm_dquot_logitem_committing
 246 };
 247
 248 /*
 249  * Initialize the dquot log item for a newly allocated dquot.
 250  * The dquot isn't locked at this point, but it isn't on any of the lists
 251  * either, so we don't care.
 252  */
 253 void
 254 xfs_qm_dquot_logitem_init(
 255         struct xfs_dquot        *dqp)
 256 {
 257         struct xfs_dq_logitem   *lp = &dqp->q_logitem;
 258
 259         xfs_log_item_init(dqp->q_mount, &lp->qli_item, XFS_LI_DQUOT,
 260                                         &xfs_dquot_item_ops);
 261         lp->qli_dquot = dqp;
 262 }
 263
 264 /*------------------  QUOTAOFF LOG ITEMS  -------------------*/
 265
 266 static inline struct xfs_qoff_logitem *QOFF_ITEM(struct xfs_log_item *lip)
 267 {
 268         return container_of(lip, struct xfs_qoff_logitem, qql_item);
 269 }
 270
 271
 272 /*
 273  * This returns the number of iovecs needed to log the given quotaoff item.
 274  * We only need 1 iovec for an quotaoff item.  It just logs the
 275  * quotaoff_log_format structure.
 276  */
 277 STATIC void
 278 xfs_qm_qoff_logitem_size(
 279         struct xfs_log_item     *lip,
 280         int                     *nvecs,
 281         int                     *nbytes)
 282 {
 283         *nvecs += 1;
 284         *nbytes += sizeof(struct xfs_qoff_logitem);
 285 }
 286
 287 STATIC void
 288 xfs_qm_qoff_logitem_format(
 289         struct xfs_log_item     *lip,
 290         struct xfs_log_vec      *lv)
 291 {
 292         struct xfs_qoff_logitem *qflip = QOFF_ITEM(lip);
 293         struct xfs_log_iovec    *vecp = NULL;
 294         struct xfs_qoff_logformat *qlf;
 295
 296         qlf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_QUOTAOFF);
 297         qlf->qf_type = XFS_LI_QUOTAOFF;
 298         qlf->qf_size = 1;
 299         qlf->qf_flags = qflip->qql_flags;
 300         xlog_finish_iovec(lv, vecp, sizeof(struct xfs_qoff_logitem));
 301 }
 302
 303 /*
 304  * Pinning has no meaning for an quotaoff item, so just return.
 305  */
 306 STATIC void
 307 xfs_qm_qoff_logitem_pin(
 308         struct xfs_log_item     *lip)
 309 {
 310 }
 311
 312 /*
 313  * Since pinning has no meaning for an quotaoff item, unpinning does
 314  * not either.
 315  */
 316 STATIC void
 317 xfs_qm_qoff_logitem_unpin(
 318         struct xfs_log_item     *lip,
 319         int                     remove)
 320 {
 321 }
 322
 323 /*
 324  * There isn't much you can do to push a quotaoff item.  It is simply
 325  * stuck waiting for the log to be flushed to disk.
 326  */
 327 STATIC uint
 328 xfs_qm_qoff_logitem_push(
 329         struct xfs_log_item     *lip,
 330         struct list_head        *buffer_list)
 331 {
 332         return XFS_ITEM_LOCKED;
 333 }
 334
 335 /*
 336  * Quotaoff items have no locking or pushing, so return failure
 337  * so that the caller doesn't bother with us.
 338  */
 339 STATIC void
 340 xfs_qm_qoff_logitem_unlock(
 341         struct xfs_log_item     *lip)
 342 {
 343 }
 344
 345 /*
 346  * The quotaoff-start-item is logged only once and cannot be moved in the log,
 347  * so simply return the lsn at which it's been logged.
 348  */
 349 STATIC xfs_lsn_t
 350 xfs_qm_qoff_logitem_committed(
 351         struct xfs_log_item     *lip,
 352         xfs_lsn_t               lsn)
 353 {
 354         return lsn;
 355 }
 356
 357 STATIC xfs_lsn_t
 358 xfs_qm_qoffend_logitem_committed(
 359         struct xfs_log_item     *lip,
 360         xfs_lsn_t               lsn)
 361 {
 362         struct xfs_qoff_logitem *qfe = QOFF_ITEM(lip);
 363         struct xfs_qoff_logitem *qfs = qfe->qql_start_lip;
 364         struct xfs_ail          *ailp = qfs->qql_item.li_ailp;
 365
 366         /*
 367          * Delete the qoff-start logitem from the AIL.
 368          * xfs_trans_ail_delete() drops the AIL lock.
 369          */
 370         spin_lock(&ailp->xa_lock);
 371         xfs_trans_ail_delete(ailp, &qfs->qql_item, SHUTDOWN_LOG_IO_ERROR);
 372
 373         kmem_free(qfs);
 374         kmem_free(qfe);
 375         return (xfs_lsn_t)-1;
 376 }
 377
 378 /*
 379  * XXX rcc - don't know quite what to do with this.  I think we can
 380  * just ignore it.  The only time that isn't the case is if we allow
 381  * the client to somehow see that quotas have been turned off in which
 382  * we can't allow that to get back until the quotaoff hits the disk.
 383  * So how would that happen?  Also, do we need different routines for
 384  * quotaoff start and quotaoff end?  I suspect the answer is yes but
 385  * to be sure, I need to look at the recovery code and see how quota off
 386  * recovery is handled (do we roll forward or back or do something else).
 387  * If we roll forwards or backwards, then we need two separate routines,
 388  * one that does nothing and one that stamps in the lsn that matters
 389  * (truly makes the quotaoff irrevocable).  If we do something else,
 390  * then maybe we don't need two.
 391  */
 392 STATIC void
 393 xfs_qm_qoff_logitem_committing(
 394         struct xfs_log_item     *lip,
 395         xfs_lsn_t               commit_lsn)
 396 {
 397 }
 398
 399 static const struct xfs_item_ops xfs_qm_qoffend_logitem_ops = {
 400         .iop_size       = xfs_qm_qoff_logitem_size,
 401         .iop_format     = xfs_qm_qoff_logitem_format,
 402         .iop_pin        = xfs_qm_qoff_logitem_pin,
 403         .iop_unpin      = xfs_qm_qoff_logitem_unpin,
 404         .iop_unlock     = xfs_qm_qoff_logitem_unlock,
 405         .iop_committed  = xfs_qm_qoffend_logitem_committed,
 406         .iop_push       = xfs_qm_qoff_logitem_push,
 407         .iop_committing = xfs_qm_qoff_logitem_committing
 408 };
 409
 410 /*
 411  * This is the ops vector shared by all quotaoff-start log items.
 412  */
 413 static const struct xfs_item_ops xfs_qm_qoff_logitem_ops = {
 414         .iop_size       = xfs_qm_qoff_logitem_size,
 415         .iop_format     = xfs_qm_qoff_logitem_format,
 416         .iop_pin        = xfs_qm_qoff_logitem_pin,
 417         .iop_unpin      = xfs_qm_qoff_logitem_unpin,
 418         .iop_unlock     = xfs_qm_qoff_logitem_unlock,
 419         .iop_committed  = xfs_qm_qoff_logitem_committed,
 420         .iop_push       = xfs_qm_qoff_logitem_push,
 421         .iop_committing = xfs_qm_qoff_logitem_committing
 422 };
 423
 424 /*
 425  * Allocate and initialize an quotaoff item of the correct quota type(s).
 426  */
 427 struct xfs_qoff_logitem *
 428 xfs_qm_qoff_logitem_init(
 429         struct xfs_mount        *mp,
 430         struct xfs_qoff_logitem *start,
 431         uint                    flags)
 432 {
 433         struct xfs_qoff_logitem *qf;
 434
 435         qf = kmem_zalloc(sizeof(struct xfs_qoff_logitem), KM_SLEEP);
 436
 437         xfs_log_item_init(mp, &qf->qql_item, XFS_LI_QUOTAOFF, start ?
 438                         &xfs_qm_qoffend_logitem_ops : &xfs_qm_qoff_logitem_ops);
 439         qf->qql_item.li_mountp = mp;
 440         qf->qql_start_lip = start;
 441         qf->qql_flags = flags;
 442         return qf;
 443 }