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