fs/xfs/xfs_bmap_item.c

   1 /*
   2  * Copyright (C) 2016 Oracle.  All Rights Reserved.
   3  *
   4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it would be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write the Free Software Foundation,
  18  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
  19  */
  20 #include "xfs.h"
  21 #include "xfs_fs.h"
  22 #include "xfs_format.h"
  23 #include "xfs_log_format.h"
  24 #include "xfs_trans_resv.h"
  25 #include "xfs_bit.h"
  26 #include "xfs_mount.h"
  27 #include "xfs_defer.h"
  28 #include "xfs_inode.h"
  29 #include "xfs_trans.h"
  30 #include "xfs_trans_priv.h"
  31 #include "xfs_buf_item.h"
  32 #include "xfs_bmap_item.h"
  33 #include "xfs_log.h"
  34 #include "xfs_bmap.h"
  35 #include "xfs_icache.h"
  36 #include "xfs_trace.h"
  37 #include "xfs_bmap_btree.h"
  38 #include "xfs_trans_space.h"
  39
  40
  41 kmem_zone_t     *xfs_bui_zone;
  42 kmem_zone_t     *xfs_bud_zone;
  43
  44 static inline struct xfs_bui_log_item *BUI_ITEM(struct xfs_log_item *lip)
  45 {
  46         return container_of(lip, struct xfs_bui_log_item, bui_item);
  47 }
  48
  49 void
  50 xfs_bui_item_free(
  51         struct xfs_bui_log_item *buip)
  52 {
  53         kmem_zone_free(xfs_bui_zone, buip);
  54 }
  55
  56 STATIC void
  57 xfs_bui_item_size(
  58         struct xfs_log_item     *lip,
  59         int                     *nvecs,
  60         int                     *nbytes)
  61 {
  62         struct xfs_bui_log_item *buip = BUI_ITEM(lip);
  63
  64         *nvecs += 1;
  65         *nbytes += xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents);
  66 }
  67
  68 /*
  69  * This is called to fill in the vector of log iovecs for the
  70  * given bui log item. We use only 1 iovec, and we point that
  71  * at the bui_log_format structure embedded in the bui item.
  72  * It is at this point that we assert that all of the extent
  73  * slots in the bui item have been filled.
  74  */
  75 STATIC void
  76 xfs_bui_item_format(
  77         struct xfs_log_item     *lip,
  78         struct xfs_log_vec      *lv)
  79 {
  80         struct xfs_bui_log_item *buip = BUI_ITEM(lip);
  81         struct xfs_log_iovec    *vecp = NULL;
  82
  83         ASSERT(atomic_read(&buip->bui_next_extent) ==
  84                         buip->bui_format.bui_nextents);
  85
  86         buip->bui_format.bui_type = XFS_LI_BUI;
  87         buip->bui_format.bui_size = 1;
  88
  89         xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUI_FORMAT, &buip->bui_format,
  90                         xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents));
  91 }
  92
  93 /*
  94  * Pinning has no meaning for an bui item, so just return.
  95  */
  96 STATIC void
  97 xfs_bui_item_pin(
  98         struct xfs_log_item     *lip)
  99 {
 100 }
 101
 102 /*
 103  * The unpin operation is the last place an BUI is manipulated in the log. It is
 104  * either inserted in the AIL or aborted in the event of a log I/O error. In
 105  * either case, the BUI transaction has been successfully committed to make it
 106  * this far. Therefore, we expect whoever committed the BUI to either construct
 107  * and commit the BUD or drop the BUD's reference in the event of error. Simply
 108  * drop the log's BUI reference now that the log is done with it.
 109  */
 110 STATIC void
 111 xfs_bui_item_unpin(
 112         struct xfs_log_item     *lip,
 113         int                     remove)
 114 {
 115         struct xfs_bui_log_item *buip = BUI_ITEM(lip);
 116
 117         xfs_bui_release(buip);
 118 }
 119
 120 /*
 121  * BUI items have no locking or pushing.  However, since BUIs are pulled from
 122  * the AIL when their corresponding BUDs are committed to disk, their situation
 123  * is very similar to being pinned.  Return XFS_ITEM_PINNED so that the caller
 124  * will eventually flush the log.  This should help in getting the BUI out of
 125  * the AIL.
 126  */
 127 STATIC uint
 128 xfs_bui_item_push(
 129         struct xfs_log_item     *lip,
 130         struct list_head        *buffer_list)
 131 {
 132         return XFS_ITEM_PINNED;
 133 }
 134
 135 /*
 136  * The BUI has been either committed or aborted if the transaction has been
 137  * cancelled. If the transaction was cancelled, an BUD isn't going to be
 138  * constructed and thus we free the BUI here directly.
 139  */
 140 STATIC void
 141 xfs_bui_item_unlock(
 142         struct xfs_log_item     *lip)
 143 {
 144         if (lip->li_flags & XFS_LI_ABORTED)
 145                 xfs_bui_item_free(BUI_ITEM(lip));
 146 }
 147
 148 /*
 149  * The BUI is logged only once and cannot be moved in the log, so simply return
 150  * the lsn at which it's been logged.
 151  */
 152 STATIC xfs_lsn_t
 153 xfs_bui_item_committed(
 154         struct xfs_log_item     *lip,
 155         xfs_lsn_t               lsn)
 156 {
 157         return lsn;
 158 }
 159
 160 /*
 161  * The BUI dependency tracking op doesn't do squat.  It can't because
 162  * it doesn't know where the free extent is coming from.  The dependency
 163  * tracking has to be handled by the "enclosing" metadata object.  For
 164  * example, for inodes, the inode is locked throughout the extent freeing
 165  * so the dependency should be recorded there.
 166  */
 167 STATIC void
 168 xfs_bui_item_committing(
 169         struct xfs_log_item     *lip,
 170         xfs_lsn_t               lsn)
 171 {
 172 }
 173
 174 /*
 175  * This is the ops vector shared by all bui log items.
 176  */
 177 static const struct xfs_item_ops xfs_bui_item_ops = {
 178         .iop_size       = xfs_bui_item_size,
 179         .iop_format     = xfs_bui_item_format,
 180         .iop_pin        = xfs_bui_item_pin,
 181         .iop_unpin      = xfs_bui_item_unpin,
 182         .iop_unlock     = xfs_bui_item_unlock,
 183         .iop_committed  = xfs_bui_item_committed,
 184         .iop_push       = xfs_bui_item_push,
 185         .iop_committing = xfs_bui_item_committing,
 186 };
 187
 188 /*
 189  * Allocate and initialize an bui item with the given number of extents.
 190  */
 191 struct xfs_bui_log_item *
 192 xfs_bui_init(
 193         struct xfs_mount                *mp)
 194
 195 {
 196         struct xfs_bui_log_item         *buip;
 197
 198         buip = kmem_zone_zalloc(xfs_bui_zone, KM_SLEEP);
 199
 200         xfs_log_item_init(mp, &buip->bui_item, XFS_LI_BUI, &xfs_bui_item_ops);
 201         buip->bui_format.bui_nextents = XFS_BUI_MAX_FAST_EXTENTS;
 202         buip->bui_format.bui_id = (uintptr_t)(void *)buip;
 203         atomic_set(&buip->bui_next_extent, 0);
 204         atomic_set(&buip->bui_refcount, 2);
 205
 206         return buip;
 207 }
 208
 209 /*
 210  * Freeing the BUI requires that we remove it from the AIL if it has already
 211  * been placed there. However, the BUI may not yet have been placed in the AIL
 212  * when called by xfs_bui_release() from BUD processing due to the ordering of
 213  * committed vs unpin operations in bulk insert operations. Hence the reference
 214  * count to ensure only the last caller frees the BUI.
 215  */
 216 void
 217 xfs_bui_release(
 218         struct xfs_bui_log_item *buip)
 219 {
 220         ASSERT(atomic_read(&buip->bui_refcount) > 0);
 221         if (atomic_dec_and_test(&buip->bui_refcount)) {
 222                 xfs_trans_ail_remove(&buip->bui_item, SHUTDOWN_LOG_IO_ERROR);
 223                 xfs_bui_item_free(buip);
 224         }
 225 }
 226
 227 static inline struct xfs_bud_log_item *BUD_ITEM(struct xfs_log_item *lip)
 228 {
 229         return container_of(lip, struct xfs_bud_log_item, bud_item);
 230 }
 231
 232 STATIC void
 233 xfs_bud_item_size(
 234         struct xfs_log_item     *lip,
 235         int                     *nvecs,
 236         int                     *nbytes)
 237 {
 238         *nvecs += 1;
 239         *nbytes += sizeof(struct xfs_bud_log_format);
 240 }
 241
 242 /*
 243  * This is called to fill in the vector of log iovecs for the
 244  * given bud log item. We use only 1 iovec, and we point that
 245  * at the bud_log_format structure embedded in the bud item.
 246  * It is at this point that we assert that all of the extent
 247  * slots in the bud item have been filled.
 248  */
 249 STATIC void
 250 xfs_bud_item_format(
 251         struct xfs_log_item     *lip,
 252         struct xfs_log_vec      *lv)
 253 {
 254         struct xfs_bud_log_item *budp = BUD_ITEM(lip);
 255         struct xfs_log_iovec    *vecp = NULL;
 256
 257         budp->bud_format.bud_type = XFS_LI_BUD;
 258         budp->bud_format.bud_size = 1;
 259
 260         xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUD_FORMAT, &budp->bud_format,
 261                         sizeof(struct xfs_bud_log_format));
 262 }
 263
 264 /*
 265  * Pinning has no meaning for an bud item, so just return.
 266  */
 267 STATIC void
 268 xfs_bud_item_pin(
 269         struct xfs_log_item     *lip)
 270 {
 271 }
 272
 273 /*
 274  * Since pinning has no meaning for an bud item, unpinning does
 275  * not either.
 276  */
 277 STATIC void
 278 xfs_bud_item_unpin(
 279         struct xfs_log_item     *lip,
 280         int                     remove)
 281 {
 282 }
 283
 284 /*
 285  * There isn't much you can do to push on an bud item.  It is simply stuck
 286  * waiting for the log to be flushed to disk.
 287  */
 288 STATIC uint
 289 xfs_bud_item_push(
 290         struct xfs_log_item     *lip,
 291         struct list_head        *buffer_list)
 292 {
 293         return XFS_ITEM_PINNED;
 294 }
 295
 296 /*
 297  * The BUD is either committed or aborted if the transaction is cancelled. If
 298  * the transaction is cancelled, drop our reference to the BUI and free the
 299  * BUD.
 300  */
 301 STATIC void
 302 xfs_bud_item_unlock(
 303         struct xfs_log_item     *lip)
 304 {
 305         struct xfs_bud_log_item *budp = BUD_ITEM(lip);
 306
 307         if (lip->li_flags & XFS_LI_ABORTED) {
 308                 xfs_bui_release(budp->bud_buip);
 309                 kmem_zone_free(xfs_bud_zone, budp);
 310         }
 311 }
 312
 313 /*
 314  * When the bud item is committed to disk, all we need to do is delete our
 315  * reference to our partner bui item and then free ourselves. Since we're
 316  * freeing ourselves we must return -1 to keep the transaction code from
 317  * further referencing this item.
 318  */
 319 STATIC xfs_lsn_t
 320 xfs_bud_item_committed(
 321         struct xfs_log_item     *lip,
 322         xfs_lsn_t               lsn)
 323 {
 324         struct xfs_bud_log_item *budp = BUD_ITEM(lip);
 325
 326         /*
 327          * Drop the BUI reference regardless of whether the BUD has been
 328          * aborted. Once the BUD transaction is constructed, it is the sole
 329          * responsibility of the BUD to release the BUI (even if the BUI is
 330          * aborted due to log I/O error).
 331          */
 332         xfs_bui_release(budp->bud_buip);
 333         kmem_zone_free(xfs_bud_zone, budp);
 334
 335         return (xfs_lsn_t)-1;
 336 }
 337
 338 /*
 339  * The BUD dependency tracking op doesn't do squat.  It can't because
 340  * it doesn't know where the free extent is coming from.  The dependency
 341  * tracking has to be handled by the "enclosing" metadata object.  For
 342  * example, for inodes, the inode is locked throughout the extent freeing
 343  * so the dependency should be recorded there.
 344  */
 345 STATIC void
 346 xfs_bud_item_committing(
 347         struct xfs_log_item     *lip,
 348         xfs_lsn_t               lsn)
 349 {
 350 }
 351
 352 /*
 353  * This is the ops vector shared by all bud log items.
 354  */
 355 static const struct xfs_item_ops xfs_bud_item_ops = {
 356         .iop_size       = xfs_bud_item_size,
 357         .iop_format     = xfs_bud_item_format,
 358         .iop_pin        = xfs_bud_item_pin,
 359         .iop_unpin      = xfs_bud_item_unpin,
 360         .iop_unlock     = xfs_bud_item_unlock,
 361         .iop_committed  = xfs_bud_item_committed,
 362         .iop_push       = xfs_bud_item_push,
 363         .iop_committing = xfs_bud_item_committing,
 364 };
 365
 366 /*
 367  * Allocate and initialize an bud item with the given number of extents.
 368  */
 369 struct xfs_bud_log_item *
 370 xfs_bud_init(
 371         struct xfs_mount                *mp,
 372         struct xfs_bui_log_item         *buip)
 373
 374 {
 375         struct xfs_bud_log_item *budp;
 376
 377         budp = kmem_zone_zalloc(xfs_bud_zone, KM_SLEEP);
 378         xfs_log_item_init(mp, &budp->bud_item, XFS_LI_BUD, &xfs_bud_item_ops);
 379         budp->bud_buip = buip;
 380         budp->bud_format.bud_bui_id = buip->bui_format.bui_id;
 381
 382         return budp;
 383 }
 384
 385 /*
 386  * Process a bmap update intent item that was recovered from the log.
 387  * We need to update some inode's bmbt.
 388  */
 389 int
 390 xfs_bui_recover(
 391         struct xfs_mount                *mp,
 392         struct xfs_bui_log_item         *buip)
 393 {
 394         int                             error = 0;
 395         unsigned int                    bui_type;
 396         struct xfs_map_extent           *bmap;
 397         xfs_fsblock_t                   startblock_fsb;
 398         xfs_fsblock_t                   inode_fsb;
 399         xfs_filblks_t                   count;
 400         bool                            op_ok;
 401         struct xfs_bud_log_item         *budp;
 402         enum xfs_bmap_intent_type       type;
 403         int                             whichfork;
 404         xfs_exntst_t                    state;
 405         struct xfs_trans                *tp;
 406         struct xfs_inode                *ip = NULL;
 407         struct xfs_defer_ops            dfops;
 408         struct xfs_bmbt_irec            irec;
 409         xfs_fsblock_t                   firstfsb;
 410
 411         ASSERT(!test_bit(XFS_BUI_RECOVERED, &buip->bui_flags));
 412
 413         /* Only one mapping operation per BUI... */
 414         if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS) {
 415                 set_bit(XFS_BUI_RECOVERED, &buip->bui_flags);
 416                 xfs_bui_release(buip);
 417                 return -EIO;
 418         }
 419
 420         /*
 421          * First check the validity of the extent described by the
 422          * BUI.  If anything is bad, then toss the BUI.
 423          */
 424         bmap = &buip->bui_format.bui_extents[0];
 425         startblock_fsb = XFS_BB_TO_FSB(mp,
 426                            XFS_FSB_TO_DADDR(mp, bmap->me_startblock));
 427         inode_fsb = XFS_BB_TO_FSB(mp, XFS_FSB_TO_DADDR(mp,
 428                         XFS_INO_TO_FSB(mp, bmap->me_owner)));
 429         switch (bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK) {
 430         case XFS_BMAP_MAP:
 431         case XFS_BMAP_UNMAP:
 432                 op_ok = true;
 433                 break;
 434         default:
 435                 op_ok = false;
 436                 break;
 437         }
 438         if (!op_ok || startblock_fsb == 0 ||
 439             bmap->me_len == 0 ||
 440             inode_fsb == 0 ||
 441             startblock_fsb >= mp->m_sb.sb_dblocks ||
 442             bmap->me_len >= mp->m_sb.sb_agblocks ||
 443             inode_fsb >= mp->m_sb.sb_dblocks ||
 444             (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS)) {
 445                 /*
 446                  * This will pull the BUI from the AIL and
 447                  * free the memory associated with it.
 448                  */
 449                 set_bit(XFS_BUI_RECOVERED, &buip->bui_flags);
 450                 xfs_bui_release(buip);
 451                 return -EIO;
 452         }
 453
 454         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
 455                         XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK), 0, 0, &tp);
 456         if (error)
 457                 return error;
 458         budp = xfs_trans_get_bud(tp, buip);
 459
 460         /* Grab the inode. */
 461         error = xfs_iget(mp, tp, bmap->me_owner, 0, XFS_ILOCK_EXCL, &ip);
 462         if (error)
 463                 goto err_inode;
 464
 465         if (VFS_I(ip)->i_nlink == 0)
 466                 xfs_iflags_set(ip, XFS_IRECOVERY);
 467         xfs_defer_init(&dfops, &firstfsb);
 468
 469         /* Process deferred bmap item. */
 470         state = (bmap->me_flags & XFS_BMAP_EXTENT_UNWRITTEN) ?
 471                         XFS_EXT_UNWRITTEN : XFS_EXT_NORM;
 472         whichfork = (bmap->me_flags & XFS_BMAP_EXTENT_ATTR_FORK) ?
 473                         XFS_ATTR_FORK : XFS_DATA_FORK;
 474         bui_type = bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK;
 475         switch (bui_type) {
 476         case XFS_BMAP_MAP:
 477         case XFS_BMAP_UNMAP:
 478                 type = bui_type;
 479                 break;
 480         default:
 481                 error = -EFSCORRUPTED;
 482                 goto err_dfops;
 483         }
 484         xfs_trans_ijoin(tp, ip, 0);
 485
 486         count = bmap->me_len;
 487         error = xfs_trans_log_finish_bmap_update(tp, budp, &dfops, type,
 488                         ip, whichfork, bmap->me_startoff,
 489                         bmap->me_startblock, &count, state);
 490         if (error)
 491                 goto err_dfops;
 492
 493         if (count > 0) {
 494                 ASSERT(type == XFS_BMAP_UNMAP);
 495                 irec.br_startblock = bmap->me_startblock;
 496                 irec.br_blockcount = count;
 497                 irec.br_startoff = bmap->me_startoff;
 498                 irec.br_state = state;
 499                 error = xfs_bmap_unmap_extent(tp->t_mountp, &dfops, ip, &irec);
 500                 if (error)
 501                         goto err_dfops;
 502         }
 503
 504         /* Finish transaction, free inodes. */
 505         error = xfs_defer_finish(&tp, &dfops, NULL);
 506         if (error)
 507                 goto err_dfops;
 508
 509         set_bit(XFS_BUI_RECOVERED, &buip->bui_flags);
 510         error = xfs_trans_commit(tp);
 511         xfs_iunlock(ip, XFS_ILOCK_EXCL);
 512         IRELE(ip);
 513
 514         return error;
 515
 516 err_dfops:
 517         xfs_defer_cancel(&dfops);
 518 err_inode:
 519         xfs_trans_cancel(tp);
 520         if (ip) {
 521                 xfs_iunlock(ip, XFS_ILOCK_EXCL);
 522                 IRELE(ip);
 523         }
 524         return error;
 525 }