linux/fs/xfs/xfs_trans_buf.c
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   1/*
   2 * Copyright (c) 2000-2002,2005 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_types.h"
  21#include "xfs_log.h"
  22#include "xfs_trans.h"
  23#include "xfs_sb.h"
  24#include "xfs_ag.h"
  25#include "xfs_mount.h"
  26#include "xfs_bmap_btree.h"
  27#include "xfs_alloc_btree.h"
  28#include "xfs_ialloc_btree.h"
  29#include "xfs_dinode.h"
  30#include "xfs_inode.h"
  31#include "xfs_buf_item.h"
  32#include "xfs_trans_priv.h"
  33#include "xfs_error.h"
  34#include "xfs_trace.h"
  35
  36/*
  37 * Check to see if a buffer matching the given parameters is already
  38 * a part of the given transaction.
  39 */
  40STATIC struct xfs_buf *
  41xfs_trans_buf_item_match(
  42        struct xfs_trans        *tp,
  43        struct xfs_buftarg      *target,
  44        struct xfs_buf_map      *map,
  45        int                     nmaps)
  46{
  47        struct xfs_log_item_desc *lidp;
  48        struct xfs_buf_log_item *blip;
  49        int                     len = 0;
  50        int                     i;
  51
  52        for (i = 0; i < nmaps; i++)
  53                len += map[i].bm_len;
  54
  55        list_for_each_entry(lidp, &tp->t_items, lid_trans) {
  56                blip = (struct xfs_buf_log_item *)lidp->lid_item;
  57                if (blip->bli_item.li_type == XFS_LI_BUF &&
  58                    blip->bli_buf->b_target == target &&
  59                    XFS_BUF_ADDR(blip->bli_buf) == map[0].bm_bn &&
  60                    blip->bli_buf->b_length == len) {
  61                        ASSERT(blip->bli_buf->b_map_count == nmaps);
  62                        return blip->bli_buf;
  63                }
  64        }
  65
  66        return NULL;
  67}
  68
  69/*
  70 * Add the locked buffer to the transaction.
  71 *
  72 * The buffer must be locked, and it cannot be associated with any
  73 * transaction.
  74 *
  75 * If the buffer does not yet have a buf log item associated with it,
  76 * then allocate one for it.  Then add the buf item to the transaction.
  77 */
  78STATIC void
  79_xfs_trans_bjoin(
  80        struct xfs_trans        *tp,
  81        struct xfs_buf          *bp,
  82        int                     reset_recur)
  83{
  84        struct xfs_buf_log_item *bip;
  85
  86        ASSERT(bp->b_transp == NULL);
  87
  88        /*
  89         * The xfs_buf_log_item pointer is stored in b_fsprivate.  If
  90         * it doesn't have one yet, then allocate one and initialize it.
  91         * The checks to see if one is there are in xfs_buf_item_init().
  92         */
  93        xfs_buf_item_init(bp, tp->t_mountp);
  94        bip = bp->b_fspriv;
  95        ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
  96        ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
  97        ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
  98        if (reset_recur)
  99                bip->bli_recur = 0;
 100
 101        /*
 102         * Take a reference for this transaction on the buf item.
 103         */
 104        atomic_inc(&bip->bli_refcount);
 105
 106        /*
 107         * Get a log_item_desc to point at the new item.
 108         */
 109        xfs_trans_add_item(tp, &bip->bli_item);
 110
 111        /*
 112         * Initialize b_fsprivate2 so we can find it with incore_match()
 113         * in xfs_trans_get_buf() and friends above.
 114         */
 115        bp->b_transp = tp;
 116
 117}
 118
 119void
 120xfs_trans_bjoin(
 121        struct xfs_trans        *tp,
 122        struct xfs_buf          *bp)
 123{
 124        _xfs_trans_bjoin(tp, bp, 0);
 125        trace_xfs_trans_bjoin(bp->b_fspriv);
 126}
 127
 128/*
 129 * Get and lock the buffer for the caller if it is not already
 130 * locked within the given transaction.  If it is already locked
 131 * within the transaction, just increment its lock recursion count
 132 * and return a pointer to it.
 133 *
 134 * If the transaction pointer is NULL, make this just a normal
 135 * get_buf() call.
 136 */
 137struct xfs_buf *
 138xfs_trans_get_buf_map(
 139        struct xfs_trans        *tp,
 140        struct xfs_buftarg      *target,
 141        struct xfs_buf_map      *map,
 142        int                     nmaps,
 143        xfs_buf_flags_t         flags)
 144{
 145        xfs_buf_t               *bp;
 146        xfs_buf_log_item_t      *bip;
 147
 148        if (!tp)
 149                return xfs_buf_get_map(target, map, nmaps, flags);
 150
 151        /*
 152         * If we find the buffer in the cache with this transaction
 153         * pointer in its b_fsprivate2 field, then we know we already
 154         * have it locked.  In this case we just increment the lock
 155         * recursion count and return the buffer to the caller.
 156         */
 157        bp = xfs_trans_buf_item_match(tp, target, map, nmaps);
 158        if (bp != NULL) {
 159                ASSERT(xfs_buf_islocked(bp));
 160                if (XFS_FORCED_SHUTDOWN(tp->t_mountp)) {
 161                        xfs_buf_stale(bp);
 162                        XFS_BUF_DONE(bp);
 163                }
 164
 165                ASSERT(bp->b_transp == tp);
 166                bip = bp->b_fspriv;
 167                ASSERT(bip != NULL);
 168                ASSERT(atomic_read(&bip->bli_refcount) > 0);
 169                bip->bli_recur++;
 170                trace_xfs_trans_get_buf_recur(bip);
 171                return (bp);
 172        }
 173
 174        bp = xfs_buf_get_map(target, map, nmaps, flags);
 175        if (bp == NULL) {
 176                return NULL;
 177        }
 178
 179        ASSERT(!bp->b_error);
 180
 181        _xfs_trans_bjoin(tp, bp, 1);
 182        trace_xfs_trans_get_buf(bp->b_fspriv);
 183        return (bp);
 184}
 185
 186/*
 187 * Get and lock the superblock buffer of this file system for the
 188 * given transaction.
 189 *
 190 * We don't need to use incore_match() here, because the superblock
 191 * buffer is a private buffer which we keep a pointer to in the
 192 * mount structure.
 193 */
 194xfs_buf_t *
 195xfs_trans_getsb(xfs_trans_t     *tp,
 196                struct xfs_mount *mp,
 197                int             flags)
 198{
 199        xfs_buf_t               *bp;
 200        xfs_buf_log_item_t      *bip;
 201
 202        /*
 203         * Default to just trying to lock the superblock buffer
 204         * if tp is NULL.
 205         */
 206        if (tp == NULL) {
 207                return (xfs_getsb(mp, flags));
 208        }
 209
 210        /*
 211         * If the superblock buffer already has this transaction
 212         * pointer in its b_fsprivate2 field, then we know we already
 213         * have it locked.  In this case we just increment the lock
 214         * recursion count and return the buffer to the caller.
 215         */
 216        bp = mp->m_sb_bp;
 217        if (bp->b_transp == tp) {
 218                bip = bp->b_fspriv;
 219                ASSERT(bip != NULL);
 220                ASSERT(atomic_read(&bip->bli_refcount) > 0);
 221                bip->bli_recur++;
 222                trace_xfs_trans_getsb_recur(bip);
 223                return (bp);
 224        }
 225
 226        bp = xfs_getsb(mp, flags);
 227        if (bp == NULL)
 228                return NULL;
 229
 230        _xfs_trans_bjoin(tp, bp, 1);
 231        trace_xfs_trans_getsb(bp->b_fspriv);
 232        return (bp);
 233}
 234
 235#ifdef DEBUG
 236xfs_buftarg_t *xfs_error_target;
 237int     xfs_do_error;
 238int     xfs_req_num;
 239int     xfs_error_mod = 33;
 240#endif
 241
 242/*
 243 * Get and lock the buffer for the caller if it is not already
 244 * locked within the given transaction.  If it has not yet been
 245 * read in, read it from disk. If it is already locked
 246 * within the transaction and already read in, just increment its
 247 * lock recursion count and return a pointer to it.
 248 *
 249 * If the transaction pointer is NULL, make this just a normal
 250 * read_buf() call.
 251 */
 252int
 253xfs_trans_read_buf_map(
 254        struct xfs_mount        *mp,
 255        struct xfs_trans        *tp,
 256        struct xfs_buftarg      *target,
 257        struct xfs_buf_map      *map,
 258        int                     nmaps,
 259        xfs_buf_flags_t         flags,
 260        struct xfs_buf          **bpp,
 261        const struct xfs_buf_ops *ops)
 262{
 263        xfs_buf_t               *bp;
 264        xfs_buf_log_item_t      *bip;
 265        int                     error;
 266
 267        *bpp = NULL;
 268        if (!tp) {
 269                bp = xfs_buf_read_map(target, map, nmaps, flags, ops);
 270                if (!bp)
 271                        return (flags & XBF_TRYLOCK) ?
 272                                        EAGAIN : XFS_ERROR(ENOMEM);
 273
 274                if (bp->b_error) {
 275                        error = bp->b_error;
 276                        xfs_buf_ioerror_alert(bp, __func__);
 277                        XFS_BUF_UNDONE(bp);
 278                        xfs_buf_stale(bp);
 279                        xfs_buf_relse(bp);
 280                        return error;
 281                }
 282#ifdef DEBUG
 283                if (xfs_do_error) {
 284                        if (xfs_error_target == target) {
 285                                if (((xfs_req_num++) % xfs_error_mod) == 0) {
 286                                        xfs_buf_relse(bp);
 287                                        xfs_debug(mp, "Returning error!");
 288                                        return XFS_ERROR(EIO);
 289                                }
 290                        }
 291                }
 292#endif
 293                if (XFS_FORCED_SHUTDOWN(mp))
 294                        goto shutdown_abort;
 295                *bpp = bp;
 296                return 0;
 297        }
 298
 299        /*
 300         * If we find the buffer in the cache with this transaction
 301         * pointer in its b_fsprivate2 field, then we know we already
 302         * have it locked.  If it is already read in we just increment
 303         * the lock recursion count and return the buffer to the caller.
 304         * If the buffer is not yet read in, then we read it in, increment
 305         * the lock recursion count, and return it to the caller.
 306         */
 307        bp = xfs_trans_buf_item_match(tp, target, map, nmaps);
 308        if (bp != NULL) {
 309                ASSERT(xfs_buf_islocked(bp));
 310                ASSERT(bp->b_transp == tp);
 311                ASSERT(bp->b_fspriv != NULL);
 312                ASSERT(!bp->b_error);
 313                if (!(XFS_BUF_ISDONE(bp))) {
 314                        trace_xfs_trans_read_buf_io(bp, _RET_IP_);
 315                        ASSERT(!XFS_BUF_ISASYNC(bp));
 316                        ASSERT(bp->b_iodone == NULL);
 317                        XFS_BUF_READ(bp);
 318                        bp->b_ops = ops;
 319                        xfsbdstrat(tp->t_mountp, bp);
 320                        error = xfs_buf_iowait(bp);
 321                        if (error) {
 322                                xfs_buf_ioerror_alert(bp, __func__);
 323                                xfs_buf_relse(bp);
 324                                /*
 325                                 * We can gracefully recover from most read
 326                                 * errors. Ones we can't are those that happen
 327                                 * after the transaction's already dirty.
 328                                 */
 329                                if (tp->t_flags & XFS_TRANS_DIRTY)
 330                                        xfs_force_shutdown(tp->t_mountp,
 331                                                        SHUTDOWN_META_IO_ERROR);
 332                                return error;
 333                        }
 334                }
 335                /*
 336                 * We never locked this buf ourselves, so we shouldn't
 337                 * brelse it either. Just get out.
 338                 */
 339                if (XFS_FORCED_SHUTDOWN(mp)) {
 340                        trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
 341                        *bpp = NULL;
 342                        return XFS_ERROR(EIO);
 343                }
 344
 345
 346                bip = bp->b_fspriv;
 347                bip->bli_recur++;
 348
 349                ASSERT(atomic_read(&bip->bli_refcount) > 0);
 350                trace_xfs_trans_read_buf_recur(bip);
 351                *bpp = bp;
 352                return 0;
 353        }
 354
 355        bp = xfs_buf_read_map(target, map, nmaps, flags, ops);
 356        if (bp == NULL) {
 357                *bpp = NULL;
 358                return (flags & XBF_TRYLOCK) ?
 359                                        0 : XFS_ERROR(ENOMEM);
 360        }
 361        if (bp->b_error) {
 362                error = bp->b_error;
 363                xfs_buf_stale(bp);
 364                XFS_BUF_DONE(bp);
 365                xfs_buf_ioerror_alert(bp, __func__);
 366                if (tp->t_flags & XFS_TRANS_DIRTY)
 367                        xfs_force_shutdown(tp->t_mountp, SHUTDOWN_META_IO_ERROR);
 368                xfs_buf_relse(bp);
 369                return error;
 370        }
 371#ifdef DEBUG
 372        if (xfs_do_error && !(tp->t_flags & XFS_TRANS_DIRTY)) {
 373                if (xfs_error_target == target) {
 374                        if (((xfs_req_num++) % xfs_error_mod) == 0) {
 375                                xfs_force_shutdown(tp->t_mountp,
 376                                                   SHUTDOWN_META_IO_ERROR);
 377                                xfs_buf_relse(bp);
 378                                xfs_debug(mp, "Returning trans error!");
 379                                return XFS_ERROR(EIO);
 380                        }
 381                }
 382        }
 383#endif
 384        if (XFS_FORCED_SHUTDOWN(mp))
 385                goto shutdown_abort;
 386
 387        _xfs_trans_bjoin(tp, bp, 1);
 388        trace_xfs_trans_read_buf(bp->b_fspriv);
 389
 390        *bpp = bp;
 391        return 0;
 392
 393shutdown_abort:
 394        trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
 395        xfs_buf_relse(bp);
 396        *bpp = NULL;
 397        return XFS_ERROR(EIO);
 398}
 399
 400/*
 401 * Release the buffer bp which was previously acquired with one of the
 402 * xfs_trans_... buffer allocation routines if the buffer has not
 403 * been modified within this transaction.  If the buffer is modified
 404 * within this transaction, do decrement the recursion count but do
 405 * not release the buffer even if the count goes to 0.  If the buffer is not
 406 * modified within the transaction, decrement the recursion count and
 407 * release the buffer if the recursion count goes to 0.
 408 *
 409 * If the buffer is to be released and it was not modified before
 410 * this transaction began, then free the buf_log_item associated with it.
 411 *
 412 * If the transaction pointer is NULL, make this just a normal
 413 * brelse() call.
 414 */
 415void
 416xfs_trans_brelse(xfs_trans_t    *tp,
 417                 xfs_buf_t      *bp)
 418{
 419        xfs_buf_log_item_t      *bip;
 420
 421        /*
 422         * Default to a normal brelse() call if the tp is NULL.
 423         */
 424        if (tp == NULL) {
 425                ASSERT(bp->b_transp == NULL);
 426                xfs_buf_relse(bp);
 427                return;
 428        }
 429
 430        ASSERT(bp->b_transp == tp);
 431        bip = bp->b_fspriv;
 432        ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
 433        ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
 434        ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
 435        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 436
 437        trace_xfs_trans_brelse(bip);
 438
 439        /*
 440         * If the release is just for a recursive lock,
 441         * then decrement the count and return.
 442         */
 443        if (bip->bli_recur > 0) {
 444                bip->bli_recur--;
 445                return;
 446        }
 447
 448        /*
 449         * If the buffer is dirty within this transaction, we can't
 450         * release it until we commit.
 451         */
 452        if (bip->bli_item.li_desc->lid_flags & XFS_LID_DIRTY)
 453                return;
 454
 455        /*
 456         * If the buffer has been invalidated, then we can't release
 457         * it until the transaction commits to disk unless it is re-dirtied
 458         * as part of this transaction.  This prevents us from pulling
 459         * the item from the AIL before we should.
 460         */
 461        if (bip->bli_flags & XFS_BLI_STALE)
 462                return;
 463
 464        ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
 465
 466        /*
 467         * Free up the log item descriptor tracking the released item.
 468         */
 469        xfs_trans_del_item(&bip->bli_item);
 470
 471        /*
 472         * Clear the hold flag in the buf log item if it is set.
 473         * We wouldn't want the next user of the buffer to
 474         * get confused.
 475         */
 476        if (bip->bli_flags & XFS_BLI_HOLD) {
 477                bip->bli_flags &= ~XFS_BLI_HOLD;
 478        }
 479
 480        /*
 481         * Drop our reference to the buf log item.
 482         */
 483        atomic_dec(&bip->bli_refcount);
 484
 485        /*
 486         * If the buf item is not tracking data in the log, then
 487         * we must free it before releasing the buffer back to the
 488         * free pool.  Before releasing the buffer to the free pool,
 489         * clear the transaction pointer in b_fsprivate2 to dissolve
 490         * its relation to this transaction.
 491         */
 492        if (!xfs_buf_item_dirty(bip)) {
 493/***
 494                ASSERT(bp->b_pincount == 0);
 495***/
 496                ASSERT(atomic_read(&bip->bli_refcount) == 0);
 497                ASSERT(!(bip->bli_item.li_flags & XFS_LI_IN_AIL));
 498                ASSERT(!(bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF));
 499                xfs_buf_item_relse(bp);
 500        }
 501
 502        bp->b_transp = NULL;
 503        xfs_buf_relse(bp);
 504}
 505
 506/*
 507 * Mark the buffer as not needing to be unlocked when the buf item's
 508 * IOP_UNLOCK() routine is called.  The buffer must already be locked
 509 * and associated with the given transaction.
 510 */
 511/* ARGSUSED */
 512void
 513xfs_trans_bhold(xfs_trans_t     *tp,
 514                xfs_buf_t       *bp)
 515{
 516        xfs_buf_log_item_t      *bip = bp->b_fspriv;
 517
 518        ASSERT(bp->b_transp == tp);
 519        ASSERT(bip != NULL);
 520        ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
 521        ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
 522        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 523
 524        bip->bli_flags |= XFS_BLI_HOLD;
 525        trace_xfs_trans_bhold(bip);
 526}
 527
 528/*
 529 * Cancel the previous buffer hold request made on this buffer
 530 * for this transaction.
 531 */
 532void
 533xfs_trans_bhold_release(xfs_trans_t     *tp,
 534                        xfs_buf_t       *bp)
 535{
 536        xfs_buf_log_item_t      *bip = bp->b_fspriv;
 537
 538        ASSERT(bp->b_transp == tp);
 539        ASSERT(bip != NULL);
 540        ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
 541        ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
 542        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 543        ASSERT(bip->bli_flags & XFS_BLI_HOLD);
 544
 545        bip->bli_flags &= ~XFS_BLI_HOLD;
 546        trace_xfs_trans_bhold_release(bip);
 547}
 548
 549/*
 550 * This is called to mark bytes first through last inclusive of the given
 551 * buffer as needing to be logged when the transaction is committed.
 552 * The buffer must already be associated with the given transaction.
 553 *
 554 * First and last are numbers relative to the beginning of this buffer,
 555 * so the first byte in the buffer is numbered 0 regardless of the
 556 * value of b_blkno.
 557 */
 558void
 559xfs_trans_log_buf(xfs_trans_t   *tp,
 560                  xfs_buf_t     *bp,
 561                  uint          first,
 562                  uint          last)
 563{
 564        xfs_buf_log_item_t      *bip = bp->b_fspriv;
 565
 566        ASSERT(bp->b_transp == tp);
 567        ASSERT(bip != NULL);
 568        ASSERT(first <= last && last < BBTOB(bp->b_length));
 569        ASSERT(bp->b_iodone == NULL ||
 570               bp->b_iodone == xfs_buf_iodone_callbacks);
 571
 572        /*
 573         * Mark the buffer as needing to be written out eventually,
 574         * and set its iodone function to remove the buffer's buf log
 575         * item from the AIL and free it when the buffer is flushed
 576         * to disk.  See xfs_buf_attach_iodone() for more details
 577         * on li_cb and xfs_buf_iodone_callbacks().
 578         * If we end up aborting this transaction, we trap this buffer
 579         * inside the b_bdstrat callback so that this won't get written to
 580         * disk.
 581         */
 582        XFS_BUF_DONE(bp);
 583
 584        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 585        bp->b_iodone = xfs_buf_iodone_callbacks;
 586        bip->bli_item.li_cb = xfs_buf_iodone;
 587
 588        trace_xfs_trans_log_buf(bip);
 589
 590        /*
 591         * If we invalidated the buffer within this transaction, then
 592         * cancel the invalidation now that we're dirtying the buffer
 593         * again.  There are no races with the code in xfs_buf_item_unpin(),
 594         * because we have a reference to the buffer this entire time.
 595         */
 596        if (bip->bli_flags & XFS_BLI_STALE) {
 597                bip->bli_flags &= ~XFS_BLI_STALE;
 598                ASSERT(XFS_BUF_ISSTALE(bp));
 599                XFS_BUF_UNSTALE(bp);
 600                bip->__bli_format.blf_flags &= ~XFS_BLF_CANCEL;
 601        }
 602
 603        tp->t_flags |= XFS_TRANS_DIRTY;
 604        bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
 605
 606        /*
 607         * If we have an ordered buffer we are not logging any dirty range but
 608         * it still needs to be marked dirty and that it has been logged.
 609         */
 610        bip->bli_flags |= XFS_BLI_DIRTY | XFS_BLI_LOGGED;
 611        if (!(bip->bli_flags & XFS_BLI_ORDERED))
 612                xfs_buf_item_log(bip, first, last);
 613}
 614
 615
 616/*
 617 * Invalidate a buffer that is being used within a transaction.
 618 *
 619 * Typically this is because the blocks in the buffer are being freed, so we
 620 * need to prevent it from being written out when we're done.  Allowing it
 621 * to be written again might overwrite data in the free blocks if they are
 622 * reallocated to a file.
 623 *
 624 * We prevent the buffer from being written out by marking it stale.  We can't
 625 * get rid of the buf log item at this point because the buffer may still be
 626 * pinned by another transaction.  If that is the case, then we'll wait until
 627 * the buffer is committed to disk for the last time (we can tell by the ref
 628 * count) and free it in xfs_buf_item_unpin().  Until that happens we will
 629 * keep the buffer locked so that the buffer and buf log item are not reused.
 630 *
 631 * We also set the XFS_BLF_CANCEL flag in the buf log format structure and log
 632 * the buf item.  This will be used at recovery time to determine that copies
 633 * of the buffer in the log before this should not be replayed.
 634 *
 635 * We mark the item descriptor and the transaction dirty so that we'll hold
 636 * the buffer until after the commit.
 637 *
 638 * Since we're invalidating the buffer, we also clear the state about which
 639 * parts of the buffer have been logged.  We also clear the flag indicating
 640 * that this is an inode buffer since the data in the buffer will no longer
 641 * be valid.
 642 *
 643 * We set the stale bit in the buffer as well since we're getting rid of it.
 644 */
 645void
 646xfs_trans_binval(
 647        xfs_trans_t     *tp,
 648        xfs_buf_t       *bp)
 649{
 650        xfs_buf_log_item_t      *bip = bp->b_fspriv;
 651        int                     i;
 652
 653        ASSERT(bp->b_transp == tp);
 654        ASSERT(bip != NULL);
 655        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 656
 657        trace_xfs_trans_binval(bip);
 658
 659        if (bip->bli_flags & XFS_BLI_STALE) {
 660                /*
 661                 * If the buffer is already invalidated, then
 662                 * just return.
 663                 */
 664                ASSERT(XFS_BUF_ISSTALE(bp));
 665                ASSERT(!(bip->bli_flags & (XFS_BLI_LOGGED | XFS_BLI_DIRTY)));
 666                ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_INODE_BUF));
 667                ASSERT(!(bip->__bli_format.blf_flags & XFS_BLFT_MASK));
 668                ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL);
 669                ASSERT(bip->bli_item.li_desc->lid_flags & XFS_LID_DIRTY);
 670                ASSERT(tp->t_flags & XFS_TRANS_DIRTY);
 671                return;
 672        }
 673
 674        xfs_buf_stale(bp);
 675
 676        bip->bli_flags |= XFS_BLI_STALE;
 677        bip->bli_flags &= ~(XFS_BLI_INODE_BUF | XFS_BLI_LOGGED | XFS_BLI_DIRTY);
 678        bip->__bli_format.blf_flags &= ~XFS_BLF_INODE_BUF;
 679        bip->__bli_format.blf_flags |= XFS_BLF_CANCEL;
 680        bip->__bli_format.blf_flags &= ~XFS_BLFT_MASK;
 681        for (i = 0; i < bip->bli_format_count; i++) {
 682                memset(bip->bli_formats[i].blf_data_map, 0,
 683                       (bip->bli_formats[i].blf_map_size * sizeof(uint)));
 684        }
 685        bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
 686        tp->t_flags |= XFS_TRANS_DIRTY;
 687}
 688
 689/*
 690 * This call is used to indicate that the buffer contains on-disk inodes which
 691 * must be handled specially during recovery.  They require special handling
 692 * because only the di_next_unlinked from the inodes in the buffer should be
 693 * recovered.  The rest of the data in the buffer is logged via the inodes
 694 * themselves.
 695 *
 696 * All we do is set the XFS_BLI_INODE_BUF flag in the items flags so it can be
 697 * transferred to the buffer's log format structure so that we'll know what to
 698 * do at recovery time.
 699 */
 700void
 701xfs_trans_inode_buf(
 702        xfs_trans_t     *tp,
 703        xfs_buf_t       *bp)
 704{
 705        xfs_buf_log_item_t      *bip = bp->b_fspriv;
 706
 707        ASSERT(bp->b_transp == tp);
 708        ASSERT(bip != NULL);
 709        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 710
 711        bip->bli_flags |= XFS_BLI_INODE_BUF;
 712        xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
 713}
 714
 715/*
 716 * This call is used to indicate that the buffer is going to
 717 * be staled and was an inode buffer. This means it gets
 718 * special processing during unpin - where any inodes
 719 * associated with the buffer should be removed from ail.
 720 * There is also special processing during recovery,
 721 * any replay of the inodes in the buffer needs to be
 722 * prevented as the buffer may have been reused.
 723 */
 724void
 725xfs_trans_stale_inode_buf(
 726        xfs_trans_t     *tp,
 727        xfs_buf_t       *bp)
 728{
 729        xfs_buf_log_item_t      *bip = bp->b_fspriv;
 730
 731        ASSERT(bp->b_transp == tp);
 732        ASSERT(bip != NULL);
 733        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 734
 735        bip->bli_flags |= XFS_BLI_STALE_INODE;
 736        bip->bli_item.li_cb = xfs_buf_iodone;
 737        xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
 738}
 739
 740/*
 741 * Mark the buffer as being one which contains newly allocated
 742 * inodes.  We need to make sure that even if this buffer is
 743 * relogged as an 'inode buf' we still recover all of the inode
 744 * images in the face of a crash.  This works in coordination with
 745 * xfs_buf_item_committed() to ensure that the buffer remains in the
 746 * AIL at its original location even after it has been relogged.
 747 */
 748/* ARGSUSED */
 749void
 750xfs_trans_inode_alloc_buf(
 751        xfs_trans_t     *tp,
 752        xfs_buf_t       *bp)
 753{
 754        xfs_buf_log_item_t      *bip = bp->b_fspriv;
 755
 756        ASSERT(bp->b_transp == tp);
 757        ASSERT(bip != NULL);
 758        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 759
 760        bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF;
 761        xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
 762}
 763
 764/*
 765 * Mark the buffer as ordered for this transaction. This means
 766 * that the contents of the buffer are not recorded in the transaction
 767 * but it is tracked in the AIL as though it was. This allows us
 768 * to record logical changes in transactions rather than the physical
 769 * changes we make to the buffer without changing writeback ordering
 770 * constraints of metadata buffers.
 771 */
 772void
 773xfs_trans_ordered_buf(
 774        struct xfs_trans        *tp,
 775        struct xfs_buf          *bp)
 776{
 777        struct xfs_buf_log_item *bip = bp->b_fspriv;
 778
 779        ASSERT(bp->b_transp == tp);
 780        ASSERT(bip != NULL);
 781        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 782
 783        bip->bli_flags |= XFS_BLI_ORDERED;
 784        trace_xfs_buf_item_ordered(bip);
 785}
 786
 787/*
 788 * Set the type of the buffer for log recovery so that it can correctly identify
 789 * and hence attach the correct buffer ops to the buffer after replay.
 790 */
 791void
 792xfs_trans_buf_set_type(
 793        struct xfs_trans        *tp,
 794        struct xfs_buf          *bp,
 795        enum xfs_blft           type)
 796{
 797        struct xfs_buf_log_item *bip = bp->b_fspriv;
 798
 799        if (!tp)
 800                return;
 801
 802        ASSERT(bp->b_transp == tp);
 803        ASSERT(bip != NULL);
 804        ASSERT(atomic_read(&bip->bli_refcount) > 0);
 805
 806        xfs_blft_to_flags(&bip->__bli_format, type);
 807}
 808
 809void
 810xfs_trans_buf_copy_type(
 811        struct xfs_buf          *dst_bp,
 812        struct xfs_buf          *src_bp)
 813{
 814        struct xfs_buf_log_item *sbip = src_bp->b_fspriv;
 815        struct xfs_buf_log_item *dbip = dst_bp->b_fspriv;
 816        enum xfs_blft           type;
 817
 818        type = xfs_blft_from_flags(&sbip->__bli_format);
 819        xfs_blft_to_flags(&dbip->__bli_format, type);
 820}
 821
 822/*
 823 * Similar to xfs_trans_inode_buf(), this marks the buffer as a cluster of
 824 * dquots. However, unlike in inode buffer recovery, dquot buffers get
 825 * recovered in their entirety. (Hence, no XFS_BLI_DQUOT_ALLOC_BUF flag).
 826 * The only thing that makes dquot buffers different from regular
 827 * buffers is that we must not replay dquot bufs when recovering
 828 * if a _corresponding_ quotaoff has happened. We also have to distinguish
 829 * between usr dquot bufs and grp dquot bufs, because usr and grp quotas
 830 * can be turned off independently.
 831 */
 832/* ARGSUSED */
 833void
 834xfs_trans_dquot_buf(
 835        xfs_trans_t     *tp,
 836        xfs_buf_t       *bp,
 837        uint            type)
 838{
 839        struct xfs_buf_log_item *bip = bp->b_fspriv;
 840
 841        ASSERT(type == XFS_BLF_UDQUOT_BUF ||
 842               type == XFS_BLF_PDQUOT_BUF ||
 843               type == XFS_BLF_GDQUOT_BUF);
 844
 845        bip->__bli_format.blf_flags |= type;
 846
 847        switch (type) {
 848        case XFS_BLF_UDQUOT_BUF:
 849                type = XFS_BLFT_UDQUOT_BUF;
 850                break;
 851        case XFS_BLF_PDQUOT_BUF:
 852                type = XFS_BLFT_PDQUOT_BUF;
 853                break;
 854        case XFS_BLF_GDQUOT_BUF:
 855                type = XFS_BLFT_GDQUOT_BUF;
 856                break;
 857        default:
 858                type = XFS_BLFT_UNKNOWN_BUF;
 859                break;
 860        }
 861
 862        xfs_trans_buf_set_type(tp, bp, type);
 863}
 864
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