fs/xfs/xfs_ialloc_btree.c

   1 /*
   2  * Copyright (c) 2000-2001,2005 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_bit.h"
  22 #include "xfs_log.h"
  23 #include "xfs_inum.h"
  24 #include "xfs_trans.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_dir2.h"
  28 #include "xfs_dmapi.h"
  29 #include "xfs_mount.h"
  30 #include "xfs_bmap_btree.h"
  31 #include "xfs_alloc_btree.h"
  32 #include "xfs_ialloc_btree.h"
  33 #include "xfs_dir2_sf.h"
  34 #include "xfs_attr_sf.h"
  35 #include "xfs_dinode.h"
  36 #include "xfs_inode.h"
  37 #include "xfs_btree.h"
  38 #include "xfs_ialloc.h"
  39 #include "xfs_alloc.h"
  40 #include "xfs_error.h"
  41
  42 STATIC void xfs_inobt_log_block(xfs_trans_t *, xfs_buf_t *, int);
  43 STATIC void xfs_inobt_log_keys(xfs_btree_cur_t *, xfs_buf_t *, int, int);
  44 STATIC void xfs_inobt_log_ptrs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
  45 STATIC void xfs_inobt_log_recs(xfs_btree_cur_t *, xfs_buf_t *, int, int);
  46 STATIC int xfs_inobt_lshift(xfs_btree_cur_t *, int, int *);
  47 STATIC int xfs_inobt_newroot(xfs_btree_cur_t *, int *);
  48 STATIC int xfs_inobt_split(xfs_btree_cur_t *, int, xfs_agblock_t *,
  49                 xfs_inobt_key_t *, xfs_btree_cur_t **, int *);
  50
  51 /*
  52  * Single level of the xfs_inobt_delete record deletion routine.
  53  * Delete record pointed to by cur/level.
  54  * Remove the record from its block then rebalance the tree.
  55  * Return 0 for error, 1 for done, 2 to go on to the next level.
  56  */
  57 STATIC int                              /* error */
  58 xfs_inobt_delrec(
  59         xfs_btree_cur_t         *cur,   /* btree cursor */
  60         int                     level,  /* level removing record from */
  61         int                     *stat)  /* fail/done/go-on */
  62 {
  63         xfs_buf_t               *agbp;  /* buffer for a.g. inode header */
  64         xfs_mount_t             *mp;    /* mount structure */
  65         xfs_agi_t               *agi;   /* allocation group inode header */
  66         xfs_inobt_block_t       *block; /* btree block record/key lives in */
  67         xfs_agblock_t           bno;    /* btree block number */
  68         xfs_buf_t               *bp;    /* buffer for block */
  69         int                     error;  /* error return value */
  70         int                     i;      /* loop index */
  71         xfs_inobt_key_t         key;    /* kp points here if block is level 0 */
  72         xfs_inobt_key_t         *kp = NULL;     /* pointer to btree keys */
  73         xfs_agblock_t           lbno;   /* left block's block number */
  74         xfs_buf_t               *lbp;   /* left block's buffer pointer */
  75         xfs_inobt_block_t       *left;  /* left btree block */
  76         xfs_inobt_key_t         *lkp;   /* left block key pointer */
  77         xfs_inobt_ptr_t         *lpp;   /* left block address pointer */
  78         int                     lrecs = 0;      /* number of records in left block */
  79         xfs_inobt_rec_t         *lrp;   /* left block record pointer */
  80         xfs_inobt_ptr_t         *pp = NULL;     /* pointer to btree addresses */
  81         int                     ptr;    /* index in btree block for this rec */
  82         xfs_agblock_t           rbno;   /* right block's block number */
  83         xfs_buf_t               *rbp;   /* right block's buffer pointer */
  84         xfs_inobt_block_t       *right; /* right btree block */
  85         xfs_inobt_key_t         *rkp;   /* right block key pointer */
  86         xfs_inobt_rec_t         *rp;    /* pointer to btree records */
  87         xfs_inobt_ptr_t         *rpp;   /* right block address pointer */
  88         int                     rrecs = 0;      /* number of records in right block */
  89         int                     numrecs;
  90         xfs_inobt_rec_t         *rrp;   /* right block record pointer */
  91         xfs_btree_cur_t         *tcur;  /* temporary btree cursor */
  92
  93         mp = cur->bc_mp;
  94
  95         /*
  96          * Get the index of the entry being deleted, check for nothing there.
  97          */
  98         ptr = cur->bc_ptrs[level];
  99         if (ptr == 0) {
 100                 *stat = 0;
 101                 return 0;
 102         }
 103
 104         /*
 105          * Get the buffer & block containing the record or key/ptr.
 106          */
 107         bp = cur->bc_bufs[level];
 108         block = XFS_BUF_TO_INOBT_BLOCK(bp);
 109 #ifdef DEBUG
 110         if ((error = xfs_btree_check_sblock(cur, block, level, bp)))
 111                 return error;
 112 #endif
 113         /*
 114          * Fail if we're off the end of the block.
 115          */
 116
 117         numrecs = be16_to_cpu(block->bb_numrecs);
 118         if (ptr > numrecs) {
 119                 *stat = 0;
 120                 return 0;
 121         }
 122         /*
 123          * It's a nonleaf.  Excise the key and ptr being deleted, by
 124          * sliding the entries past them down one.
 125          * Log the changed areas of the block.
 126          */
 127         if (level > 0) {
 128                 kp = XFS_INOBT_KEY_ADDR(block, 1, cur);
 129                 pp = XFS_INOBT_PTR_ADDR(block, 1, cur);
 130 #ifdef DEBUG
 131                 for (i = ptr; i < numrecs; i++) {
 132                         if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(pp[i]), level)))
 133                                 return error;
 134                 }
 135 #endif
 136                 if (ptr < numrecs) {
 137                         memmove(&kp[ptr - 1], &kp[ptr],
 138                                 (numrecs - ptr) * sizeof(*kp));
 139                         memmove(&pp[ptr - 1], &pp[ptr],
 140                                 (numrecs - ptr) * sizeof(*kp));
 141                         xfs_inobt_log_keys(cur, bp, ptr, numrecs - 1);
 142                         xfs_inobt_log_ptrs(cur, bp, ptr, numrecs - 1);
 143                 }
 144         }
 145         /*
 146          * It's a leaf.  Excise the record being deleted, by sliding the
 147          * entries past it down one.  Log the changed areas of the block.
 148          */
 149         else {
 150                 rp = XFS_INOBT_REC_ADDR(block, 1, cur);
 151                 if (ptr < numrecs) {
 152                         memmove(&rp[ptr - 1], &rp[ptr],
 153                                 (numrecs - ptr) * sizeof(*rp));
 154                         xfs_inobt_log_recs(cur, bp, ptr, numrecs - 1);
 155                 }
 156                 /*
 157                  * If it's the first record in the block, we'll need a key
 158                  * structure to pass up to the next level (updkey).
 159                  */
 160                 if (ptr == 1) {
 161                         key.ir_startino = rp->ir_startino;
 162                         kp = &key;
 163                 }
 164         }
 165         /*
 166          * Decrement and log the number of entries in the block.
 167          */
 168         numrecs--;
 169         block->bb_numrecs = cpu_to_be16(numrecs);
 170         xfs_inobt_log_block(cur->bc_tp, bp, XFS_BB_NUMRECS);
 171         /*
 172          * Is this the root level?  If so, we're almost done.
 173          */
 174         if (level == cur->bc_nlevels - 1) {
 175                 /*
 176                  * If this is the root level,
 177                  * and there's only one entry left,
 178                  * and it's NOT the leaf level,
 179                  * then we can get rid of this level.
 180                  */
 181                 if (numrecs == 1 && level > 0) {
 182                         agbp = cur->bc_private.a.agbp;
 183                         agi = XFS_BUF_TO_AGI(agbp);
 184                         /*
 185                          * pp is still set to the first pointer in the block.
 186                          * Make it the new root of the btree.
 187                          */
 188                         bno = be32_to_cpu(agi->agi_root);
 189                         agi->agi_root = *pp;
 190                         be32_add_cpu(&agi->agi_level, -1);
 191                         /*
 192                          * Free the block.
 193                          */
 194                         if ((error = xfs_free_extent(cur->bc_tp,
 195                                 XFS_AGB_TO_FSB(mp, cur->bc_private.a.agno, bno), 1)))
 196                                 return error;
 197                         xfs_trans_binval(cur->bc_tp, bp);
 198                         xfs_ialloc_log_agi(cur->bc_tp, agbp,
 199                                 XFS_AGI_ROOT | XFS_AGI_LEVEL);
 200                         /*
 201                          * Update the cursor so there's one fewer level.
 202                          */
 203                         cur->bc_bufs[level] = NULL;
 204                         cur->bc_nlevels--;
 205                 } else if (level > 0 &&
 206                            (error = xfs_btree_decrement(cur, level, &i)))
 207                         return error;
 208                 *stat = 1;
 209                 return 0;
 210         }
 211         /*
 212          * If we deleted the leftmost entry in the block, update the
 213          * key values above us in the tree.
 214          */
 215         if (ptr == 1 && (error = xfs_btree_updkey(cur, (union xfs_btree_key *)kp, level + 1)))
 216                 return error;
 217         /*
 218          * If the number of records remaining in the block is at least
 219          * the minimum, we're done.
 220          */
 221         if (numrecs >= XFS_INOBT_BLOCK_MINRECS(level, cur)) {
 222                 if (level > 0 &&
 223                     (error = xfs_btree_decrement(cur, level, &i)))
 224                         return error;
 225                 *stat = 1;
 226                 return 0;
 227         }
 228         /*
 229          * Otherwise, we have to move some records around to keep the
 230          * tree balanced.  Look at the left and right sibling blocks to
 231          * see if we can re-balance by moving only one record.
 232          */
 233         rbno = be32_to_cpu(block->bb_rightsib);
 234         lbno = be32_to_cpu(block->bb_leftsib);
 235         bno = NULLAGBLOCK;
 236         ASSERT(rbno != NULLAGBLOCK || lbno != NULLAGBLOCK);
 237         /*
 238          * Duplicate the cursor so our btree manipulations here won't
 239          * disrupt the next level up.
 240          */
 241         if ((error = xfs_btree_dup_cursor(cur, &tcur)))
 242                 return error;
 243         /*
 244          * If there's a right sibling, see if it's ok to shift an entry
 245          * out of it.
 246          */
 247         if (rbno != NULLAGBLOCK) {
 248                 /*
 249                  * Move the temp cursor to the last entry in the next block.
 250                  * Actually any entry but the first would suffice.
 251                  */
 252                 i = xfs_btree_lastrec(tcur, level);
 253                 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
 254                 if ((error = xfs_btree_increment(tcur, level, &i)))
 255                         goto error0;
 256                 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
 257                 i = xfs_btree_lastrec(tcur, level);
 258                 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
 259                 /*
 260                  * Grab a pointer to the block.
 261                  */
 262                 rbp = tcur->bc_bufs[level];
 263                 right = XFS_BUF_TO_INOBT_BLOCK(rbp);
 264 #ifdef DEBUG
 265                 if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
 266                         goto error0;
 267 #endif
 268                 /*
 269                  * Grab the current block number, for future use.
 270                  */
 271                 bno = be32_to_cpu(right->bb_leftsib);
 272                 /*
 273                  * If right block is full enough so that removing one entry
 274                  * won't make it too empty, and left-shifting an entry out
 275                  * of right to us works, we're done.
 276                  */
 277                 if (be16_to_cpu(right->bb_numrecs) - 1 >=
 278                      XFS_INOBT_BLOCK_MINRECS(level, cur)) {
 279                         if ((error = xfs_inobt_lshift(tcur, level, &i)))
 280                                 goto error0;
 281                         if (i) {
 282                                 ASSERT(be16_to_cpu(block->bb_numrecs) >=
 283                                        XFS_INOBT_BLOCK_MINRECS(level, cur));
 284                                 xfs_btree_del_cursor(tcur,
 285                                                      XFS_BTREE_NOERROR);
 286                                 if (level > 0 &&
 287                                     (error = xfs_btree_decrement(cur, level,
 288                                                 &i)))
 289                                         return error;
 290                                 *stat = 1;
 291                                 return 0;
 292                         }
 293                 }
 294                 /*
 295                  * Otherwise, grab the number of records in right for
 296                  * future reference, and fix up the temp cursor to point
 297                  * to our block again (last record).
 298                  */
 299                 rrecs = be16_to_cpu(right->bb_numrecs);
 300                 if (lbno != NULLAGBLOCK) {
 301                         xfs_btree_firstrec(tcur, level);
 302                         if ((error = xfs_btree_decrement(tcur, level, &i)))
 303                                 goto error0;
 304                 }
 305         }
 306         /*
 307          * If there's a left sibling, see if it's ok to shift an entry
 308          * out of it.
 309          */
 310         if (lbno != NULLAGBLOCK) {
 311                 /*
 312                  * Move the temp cursor to the first entry in the
 313                  * previous block.
 314                  */
 315                 xfs_btree_firstrec(tcur, level);
 316                 if ((error = xfs_btree_decrement(tcur, level, &i)))
 317                         goto error0;
 318                 xfs_btree_firstrec(tcur, level);
 319                 /*
 320                  * Grab a pointer to the block.
 321                  */
 322                 lbp = tcur->bc_bufs[level];
 323                 left = XFS_BUF_TO_INOBT_BLOCK(lbp);
 324 #ifdef DEBUG
 325                 if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
 326                         goto error0;
 327 #endif
 328                 /*
 329                  * Grab the current block number, for future use.
 330                  */
 331                 bno = be32_to_cpu(left->bb_rightsib);
 332                 /*
 333                  * If left block is full enough so that removing one entry
 334                  * won't make it too empty, and right-shifting an entry out
 335                  * of left to us works, we're done.
 336                  */
 337                 if (be16_to_cpu(left->bb_numrecs) - 1 >=
 338                      XFS_INOBT_BLOCK_MINRECS(level, cur)) {
 339                         if ((error = xfs_btree_rshift(tcur, level, &i)))
 340                                 goto error0;
 341                         if (i) {
 342                                 ASSERT(be16_to_cpu(block->bb_numrecs) >=
 343                                        XFS_INOBT_BLOCK_MINRECS(level, cur));
 344                                 xfs_btree_del_cursor(tcur,
 345                                                      XFS_BTREE_NOERROR);
 346                                 if (level == 0)
 347                                         cur->bc_ptrs[0]++;
 348                                 *stat = 1;
 349                                 return 0;
 350                         }
 351                 }
 352                 /*
 353                  * Otherwise, grab the number of records in right for
 354                  * future reference.
 355                  */
 356                 lrecs = be16_to_cpu(left->bb_numrecs);
 357         }
 358         /*
 359          * Delete the temp cursor, we're done with it.
 360          */
 361         xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
 362         /*
 363          * If here, we need to do a join to keep the tree balanced.
 364          */
 365         ASSERT(bno != NULLAGBLOCK);
 366         /*
 367          * See if we can join with the left neighbor block.
 368          */
 369         if (lbno != NULLAGBLOCK &&
 370             lrecs + numrecs <= XFS_INOBT_BLOCK_MAXRECS(level, cur)) {
 371                 /*
 372                  * Set "right" to be the starting block,
 373                  * "left" to be the left neighbor.
 374                  */
 375                 rbno = bno;
 376                 right = block;
 377                 rrecs = be16_to_cpu(right->bb_numrecs);
 378                 rbp = bp;
 379                 if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
 380                                 cur->bc_private.a.agno, lbno, 0, &lbp,
 381                                 XFS_INO_BTREE_REF)))
 382                         return error;
 383                 left = XFS_BUF_TO_INOBT_BLOCK(lbp);
 384                 lrecs = be16_to_cpu(left->bb_numrecs);
 385                 if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
 386                         return error;
 387         }
 388         /*
 389          * If that won't work, see if we can join with the right neighbor block.
 390          */
 391         else if (rbno != NULLAGBLOCK &&
 392                  rrecs + numrecs <= XFS_INOBT_BLOCK_MAXRECS(level, cur)) {
 393                 /*
 394                  * Set "left" to be the starting block,
 395                  * "right" to be the right neighbor.
 396                  */
 397                 lbno = bno;
 398                 left = block;
 399                 lrecs = be16_to_cpu(left->bb_numrecs);
 400                 lbp = bp;
 401                 if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
 402                                 cur->bc_private.a.agno, rbno, 0, &rbp,
 403                                 XFS_INO_BTREE_REF)))
 404                         return error;
 405                 right = XFS_BUF_TO_INOBT_BLOCK(rbp);
 406                 rrecs = be16_to_cpu(right->bb_numrecs);
 407                 if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
 408                         return error;
 409         }
 410         /*
 411          * Otherwise, we can't fix the imbalance.
 412          * Just return.  This is probably a logic error, but it's not fatal.
 413          */
 414         else {
 415                 if (level > 0 && (error = xfs_btree_decrement(cur, level, &i)))
 416                         return error;
 417                 *stat = 1;
 418                 return 0;
 419         }
 420         /*
 421          * We're now going to join "left" and "right" by moving all the stuff
 422          * in "right" to "left" and deleting "right".
 423          */
 424         if (level > 0) {
 425                 /*
 426                  * It's a non-leaf.  Move keys and pointers.
 427                  */
 428                 lkp = XFS_INOBT_KEY_ADDR(left, lrecs + 1, cur);
 429                 lpp = XFS_INOBT_PTR_ADDR(left, lrecs + 1, cur);
 430                 rkp = XFS_INOBT_KEY_ADDR(right, 1, cur);
 431                 rpp = XFS_INOBT_PTR_ADDR(right, 1, cur);
 432 #ifdef DEBUG
 433                 for (i = 0; i < rrecs; i++) {
 434                         if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i]), level)))
 435                                 return error;
 436                 }
 437 #endif
 438                 memcpy(lkp, rkp, rrecs * sizeof(*lkp));
 439                 memcpy(lpp, rpp, rrecs * sizeof(*lpp));
 440                 xfs_inobt_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
 441                 xfs_inobt_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
 442         } else {
 443                 /*
 444                  * It's a leaf.  Move records.
 445                  */
 446                 lrp = XFS_INOBT_REC_ADDR(left, lrecs + 1, cur);
 447                 rrp = XFS_INOBT_REC_ADDR(right, 1, cur);
 448                 memcpy(lrp, rrp, rrecs * sizeof(*lrp));
 449                 xfs_inobt_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
 450         }
 451         /*
 452          * If we joined with the left neighbor, set the buffer in the
 453          * cursor to the left block, and fix up the index.
 454          */
 455         if (bp != lbp) {
 456                 xfs_btree_setbuf(cur, level, lbp);
 457                 cur->bc_ptrs[level] += lrecs;
 458         }
 459         /*
 460          * If we joined with the right neighbor and there's a level above
 461          * us, increment the cursor at that level.
 462          */
 463         else if (level + 1 < cur->bc_nlevels &&
 464                  (error = xfs_btree_increment(cur, level + 1, &i)))
 465                 return error;
 466         /*
 467          * Fix up the number of records in the surviving block.
 468          */
 469         lrecs += rrecs;
 470         left->bb_numrecs = cpu_to_be16(lrecs);
 471         /*
 472          * Fix up the right block pointer in the surviving block, and log it.
 473          */
 474         left->bb_rightsib = right->bb_rightsib;
 475         xfs_inobt_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
 476         /*
 477          * If there is a right sibling now, make it point to the
 478          * remaining block.
 479          */
 480         if (be32_to_cpu(left->bb_rightsib) != NULLAGBLOCK) {
 481                 xfs_inobt_block_t       *rrblock;
 482                 xfs_buf_t               *rrbp;
 483
 484                 if ((error = xfs_btree_read_bufs(mp, cur->bc_tp,
 485                                 cur->bc_private.a.agno, be32_to_cpu(left->bb_rightsib), 0,
 486                                 &rrbp, XFS_INO_BTREE_REF)))
 487                         return error;
 488                 rrblock = XFS_BUF_TO_INOBT_BLOCK(rrbp);
 489                 if ((error = xfs_btree_check_sblock(cur, rrblock, level, rrbp)))
 490                         return error;
 491                 rrblock->bb_leftsib = cpu_to_be32(lbno);
 492                 xfs_inobt_log_block(cur->bc_tp, rrbp, XFS_BB_LEFTSIB);
 493         }
 494         /*
 495          * Free the deleting block.
 496          */
 497         if ((error = xfs_free_extent(cur->bc_tp, XFS_AGB_TO_FSB(mp,
 498                                      cur->bc_private.a.agno, rbno), 1)))
 499                 return error;
 500         xfs_trans_binval(cur->bc_tp, rbp);
 501         /*
 502          * Readjust the ptr at this level if it's not a leaf, since it's
 503          * still pointing at the deletion point, which makes the cursor
 504          * inconsistent.  If this makes the ptr 0, the caller fixes it up.
 505          * We can't use decrement because it would change the next level up.
 506          */
 507         if (level > 0)
 508                 cur->bc_ptrs[level]--;
 509         /*
 510          * Return value means the next level up has something to do.
 511          */
 512         *stat = 2;
 513         return 0;
 514
 515 error0:
 516         xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
 517         return error;
 518 }
 519
 520 /*
 521  * Insert one record/level.  Return information to the caller
 522  * allowing the next level up to proceed if necessary.
 523  */
 524 STATIC int                              /* error */
 525 xfs_inobt_insrec(
 526         xfs_btree_cur_t         *cur,   /* btree cursor */
 527         int                     level,  /* level to insert record at */
 528         xfs_agblock_t           *bnop,  /* i/o: block number inserted */
 529         xfs_inobt_rec_t         *recp,  /* i/o: record data inserted */
 530         xfs_btree_cur_t         **curp, /* output: new cursor replacing cur */
 531         int                     *stat)  /* success/failure */
 532 {
 533         xfs_inobt_block_t       *block; /* btree block record/key lives in */
 534         xfs_buf_t               *bp;    /* buffer for block */
 535         int                     error;  /* error return value */
 536         int                     i;      /* loop index */
 537         xfs_inobt_key_t         key;    /* key value being inserted */
 538         xfs_inobt_key_t         *kp=NULL;       /* pointer to btree keys */
 539         xfs_agblock_t           nbno;   /* block number of allocated block */
 540         xfs_btree_cur_t         *ncur;  /* new cursor to be used at next lvl */
 541         xfs_inobt_key_t         nkey;   /* new key value, from split */
 542         xfs_inobt_rec_t         nrec;   /* new record value, for caller */
 543         int                     numrecs;
 544         int                     optr;   /* old ptr value */
 545         xfs_inobt_ptr_t         *pp;    /* pointer to btree addresses */
 546         int                     ptr;    /* index in btree block for this rec */
 547         xfs_inobt_rec_t         *rp=NULL;       /* pointer to btree records */
 548
 549         /*
 550          * GCC doesn't understand the (arguably complex) control flow in
 551          * this function and complains about uninitialized structure fields
 552          * without this.
 553          */
 554         memset(&nrec, 0, sizeof(nrec));
 555
 556         /*
 557          * If we made it to the root level, allocate a new root block
 558          * and we're done.
 559          */
 560         if (level >= cur->bc_nlevels) {
 561                 error = xfs_inobt_newroot(cur, &i);
 562                 *bnop = NULLAGBLOCK;
 563                 *stat = i;
 564                 return error;
 565         }
 566         /*
 567          * Make a key out of the record data to be inserted, and save it.
 568          */
 569         key.ir_startino = recp->ir_startino;
 570         optr = ptr = cur->bc_ptrs[level];
 571         /*
 572          * If we're off the left edge, return failure.
 573          */
 574         if (ptr == 0) {
 575                 *stat = 0;
 576                 return 0;
 577         }
 578         /*
 579          * Get pointers to the btree buffer and block.
 580          */
 581         bp = cur->bc_bufs[level];
 582         block = XFS_BUF_TO_INOBT_BLOCK(bp);
 583         numrecs = be16_to_cpu(block->bb_numrecs);
 584 #ifdef DEBUG
 585         if ((error = xfs_btree_check_sblock(cur, block, level, bp)))
 586                 return error;
 587         /*
 588          * Check that the new entry is being inserted in the right place.
 589          */
 590         if (ptr <= numrecs) {
 591                 if (level == 0) {
 592                         rp = XFS_INOBT_REC_ADDR(block, ptr, cur);
 593                         xfs_btree_check_rec(cur->bc_btnum, recp, rp);
 594                 } else {
 595                         kp = XFS_INOBT_KEY_ADDR(block, ptr, cur);
 596                         xfs_btree_check_key(cur->bc_btnum, &key, kp);
 597                 }
 598         }
 599 #endif
 600         nbno = NULLAGBLOCK;
 601         ncur = NULL;
 602         /*
 603          * If the block is full, we can't insert the new entry until we
 604          * make the block un-full.
 605          */
 606         if (numrecs == XFS_INOBT_BLOCK_MAXRECS(level, cur)) {
 607                 /*
 608                  * First, try shifting an entry to the right neighbor.
 609                  */
 610                 if ((error = xfs_btree_rshift(cur, level, &i)))
 611                         return error;
 612                 if (i) {
 613                         /* nothing */
 614                 }
 615                 /*
 616                  * Next, try shifting an entry to the left neighbor.
 617                  */
 618                 else {
 619                         if ((error = xfs_inobt_lshift(cur, level, &i)))
 620                                 return error;
 621                         if (i) {
 622                                 optr = ptr = cur->bc_ptrs[level];
 623                         } else {
 624                                 /*
 625                                  * Next, try splitting the current block
 626                                  * in half. If this works we have to
 627                                  * re-set our variables because
 628                                  * we could be in a different block now.
 629                                  */
 630                                 if ((error = xfs_inobt_split(cur, level, &nbno,
 631                                                 &nkey, &ncur, &i)))
 632                                         return error;
 633                                 if (i) {
 634                                         bp = cur->bc_bufs[level];
 635                                         block = XFS_BUF_TO_INOBT_BLOCK(bp);
 636 #ifdef DEBUG
 637                                         if ((error = xfs_btree_check_sblock(cur,
 638                                                         block, level, bp)))
 639                                                 return error;
 640 #endif
 641                                         ptr = cur->bc_ptrs[level];
 642                                         nrec.ir_startino = nkey.ir_startino;
 643                                 } else {
 644                                         /*
 645                                          * Otherwise the insert fails.
 646                                          */
 647                                         *stat = 0;
 648                                         return 0;
 649                                 }
 650                         }
 651                 }
 652         }
 653         /*
 654          * At this point we know there's room for our new entry in the block
 655          * we're pointing at.
 656          */
 657         numrecs = be16_to_cpu(block->bb_numrecs);
 658         if (level > 0) {
 659                 /*
 660                  * It's a non-leaf entry.  Make a hole for the new data
 661                  * in the key and ptr regions of the block.
 662                  */
 663                 kp = XFS_INOBT_KEY_ADDR(block, 1, cur);
 664                 pp = XFS_INOBT_PTR_ADDR(block, 1, cur);
 665 #ifdef DEBUG
 666                 for (i = numrecs; i >= ptr; i--) {
 667                         if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(pp[i - 1]), level)))
 668                                 return error;
 669                 }
 670 #endif
 671                 memmove(&kp[ptr], &kp[ptr - 1],
 672                         (numrecs - ptr + 1) * sizeof(*kp));
 673                 memmove(&pp[ptr], &pp[ptr - 1],
 674                         (numrecs - ptr + 1) * sizeof(*pp));
 675                 /*
 676                  * Now stuff the new data in, bump numrecs and log the new data.
 677                  */
 678 #ifdef DEBUG
 679                 if ((error = xfs_btree_check_sptr(cur, *bnop, level)))
 680                         return error;
 681 #endif
 682                 kp[ptr - 1] = key;
 683                 pp[ptr - 1] = cpu_to_be32(*bnop);
 684                 numrecs++;
 685                 block->bb_numrecs = cpu_to_be16(numrecs);
 686                 xfs_inobt_log_keys(cur, bp, ptr, numrecs);
 687                 xfs_inobt_log_ptrs(cur, bp, ptr, numrecs);
 688         } else {
 689                 /*
 690                  * It's a leaf entry.  Make a hole for the new record.
 691                  */
 692                 rp = XFS_INOBT_REC_ADDR(block, 1, cur);
 693                 memmove(&rp[ptr], &rp[ptr - 1],
 694                         (numrecs - ptr + 1) * sizeof(*rp));
 695                 /*
 696                  * Now stuff the new record in, bump numrecs
 697                  * and log the new data.
 698                  */
 699                 rp[ptr - 1] = *recp;
 700                 numrecs++;
 701                 block->bb_numrecs = cpu_to_be16(numrecs);
 702                 xfs_inobt_log_recs(cur, bp, ptr, numrecs);
 703         }
 704         /*
 705          * Log the new number of records in the btree header.
 706          */
 707         xfs_inobt_log_block(cur->bc_tp, bp, XFS_BB_NUMRECS);
 708 #ifdef DEBUG
 709         /*
 710          * Check that the key/record is in the right place, now.
 711          */
 712         if (ptr < numrecs) {
 713                 if (level == 0)
 714                         xfs_btree_check_rec(cur->bc_btnum, rp + ptr - 1,
 715                                 rp + ptr);
 716                 else
 717                         xfs_btree_check_key(cur->bc_btnum, kp + ptr - 1,
 718                                 kp + ptr);
 719         }
 720 #endif
 721         /*
 722          * If we inserted at the start of a block, update the parents' keys.
 723          */
 724         if (optr == 1 && (error = xfs_btree_updkey(cur, (union xfs_btree_key *)&key, level + 1)))
 725                 return error;
 726         /*
 727          * Return the new block number, if any.
 728          * If there is one, give back a record value and a cursor too.
 729          */
 730         *bnop = nbno;
 731         if (nbno != NULLAGBLOCK) {
 732                 *recp = nrec;
 733                 *curp = ncur;
 734         }
 735         *stat = 1;
 736         return 0;
 737 }
 738
 739 /*
 740  * Log header fields from a btree block.
 741  */
 742 STATIC void
 743 xfs_inobt_log_block(
 744         xfs_trans_t             *tp,    /* transaction pointer */
 745         xfs_buf_t               *bp,    /* buffer containing btree block */
 746         int                     fields) /* mask of fields: XFS_BB_... */
 747 {
 748         int                     first;  /* first byte offset logged */
 749         int                     last;   /* last byte offset logged */
 750         static const short      offsets[] = {   /* table of offsets */
 751                 offsetof(xfs_inobt_block_t, bb_magic),
 752                 offsetof(xfs_inobt_block_t, bb_level),
 753                 offsetof(xfs_inobt_block_t, bb_numrecs),
 754                 offsetof(xfs_inobt_block_t, bb_leftsib),
 755                 offsetof(xfs_inobt_block_t, bb_rightsib),
 756                 sizeof(xfs_inobt_block_t)
 757         };
 758
 759         xfs_btree_offsets(fields, offsets, XFS_BB_NUM_BITS, &first, &last);
 760         xfs_trans_log_buf(tp, bp, first, last);
 761 }
 762
 763 /*
 764  * Log keys from a btree block (nonleaf).
 765  */
 766 STATIC void
 767 xfs_inobt_log_keys(
 768         xfs_btree_cur_t         *cur,   /* btree cursor */
 769         xfs_buf_t               *bp,    /* buffer containing btree block */
 770         int                     kfirst, /* index of first key to log */
 771         int                     klast)  /* index of last key to log */
 772 {
 773         xfs_inobt_block_t       *block; /* btree block to log from */
 774         int                     first;  /* first byte offset logged */
 775         xfs_inobt_key_t         *kp;    /* key pointer in btree block */
 776         int                     last;   /* last byte offset logged */
 777
 778         block = XFS_BUF_TO_INOBT_BLOCK(bp);
 779         kp = XFS_INOBT_KEY_ADDR(block, 1, cur);
 780         first = (int)((xfs_caddr_t)&kp[kfirst - 1] - (xfs_caddr_t)block);
 781         last = (int)(((xfs_caddr_t)&kp[klast] - 1) - (xfs_caddr_t)block);
 782         xfs_trans_log_buf(cur->bc_tp, bp, first, last);
 783 }
 784
 785 /*
 786  * Log block pointer fields from a btree block (nonleaf).
 787  */
 788 STATIC void
 789 xfs_inobt_log_ptrs(
 790         xfs_btree_cur_t         *cur,   /* btree cursor */
 791         xfs_buf_t               *bp,    /* buffer containing btree block */
 792         int                     pfirst, /* index of first pointer to log */
 793         int                     plast)  /* index of last pointer to log */
 794 {
 795         xfs_inobt_block_t       *block; /* btree block to log from */
 796         int                     first;  /* first byte offset logged */
 797         int                     last;   /* last byte offset logged */
 798         xfs_inobt_ptr_t         *pp;    /* block-pointer pointer in btree blk */
 799
 800         block = XFS_BUF_TO_INOBT_BLOCK(bp);
 801         pp = XFS_INOBT_PTR_ADDR(block, 1, cur);
 802         first = (int)((xfs_caddr_t)&pp[pfirst - 1] - (xfs_caddr_t)block);
 803         last = (int)(((xfs_caddr_t)&pp[plast] - 1) - (xfs_caddr_t)block);
 804         xfs_trans_log_buf(cur->bc_tp, bp, first, last);
 805 }
 806
 807 /*
 808  * Log records from a btree block (leaf).
 809  */
 810 STATIC void
 811 xfs_inobt_log_recs(
 812         xfs_btree_cur_t         *cur,   /* btree cursor */
 813         xfs_buf_t               *bp,    /* buffer containing btree block */
 814         int                     rfirst, /* index of first record to log */
 815         int                     rlast)  /* index of last record to log */
 816 {
 817         xfs_inobt_block_t       *block; /* btree block to log from */
 818         int                     first;  /* first byte offset logged */
 819         int                     last;   /* last byte offset logged */
 820         xfs_inobt_rec_t         *rp;    /* record pointer for btree block */
 821
 822         block = XFS_BUF_TO_INOBT_BLOCK(bp);
 823         rp = XFS_INOBT_REC_ADDR(block, 1, cur);
 824         first = (int)((xfs_caddr_t)&rp[rfirst - 1] - (xfs_caddr_t)block);
 825         last = (int)(((xfs_caddr_t)&rp[rlast] - 1) - (xfs_caddr_t)block);
 826         xfs_trans_log_buf(cur->bc_tp, bp, first, last);
 827 }
 828
 829 /*
 830  * Move 1 record left from cur/level if possible.
 831  * Update cur to reflect the new path.
 832  */
 833 STATIC int                              /* error */
 834 xfs_inobt_lshift(
 835         xfs_btree_cur_t         *cur,   /* btree cursor */
 836         int                     level,  /* level to shift record on */
 837         int                     *stat)  /* success/failure */
 838 {
 839         int                     error;  /* error return value */
 840 #ifdef DEBUG
 841         int                     i;      /* loop index */
 842 #endif
 843         xfs_inobt_key_t         key;    /* key value for leaf level upward */
 844         xfs_buf_t               *lbp;   /* buffer for left neighbor block */
 845         xfs_inobt_block_t       *left;  /* left neighbor btree block */
 846         xfs_inobt_key_t         *lkp=NULL;      /* key pointer for left block */
 847         xfs_inobt_ptr_t         *lpp;   /* address pointer for left block */
 848         xfs_inobt_rec_t         *lrp=NULL;      /* record pointer for left block */
 849         int                     nrec;   /* new number of left block entries */
 850         xfs_buf_t               *rbp;   /* buffer for right (current) block */
 851         xfs_inobt_block_t       *right; /* right (current) btree block */
 852         xfs_inobt_key_t         *rkp=NULL;      /* key pointer for right block */
 853         xfs_inobt_ptr_t         *rpp=NULL;      /* address pointer for right block */
 854         xfs_inobt_rec_t         *rrp=NULL;      /* record pointer for right block */
 855
 856         /*
 857          * Set up variables for this block as "right".
 858          */
 859         rbp = cur->bc_bufs[level];
 860         right = XFS_BUF_TO_INOBT_BLOCK(rbp);
 861 #ifdef DEBUG
 862         if ((error = xfs_btree_check_sblock(cur, right, level, rbp)))
 863                 return error;
 864 #endif
 865         /*
 866          * If we've got no left sibling then we can't shift an entry left.
 867          */
 868         if (be32_to_cpu(right->bb_leftsib) == NULLAGBLOCK) {
 869                 *stat = 0;
 870                 return 0;
 871         }
 872         /*
 873          * If the cursor entry is the one that would be moved, don't
 874          * do it... it's too complicated.
 875          */
 876         if (cur->bc_ptrs[level] <= 1) {
 877                 *stat = 0;
 878                 return 0;
 879         }
 880         /*
 881          * Set up the left neighbor as "left".
 882          */
 883         if ((error = xfs_btree_read_bufs(cur->bc_mp, cur->bc_tp,
 884                         cur->bc_private.a.agno, be32_to_cpu(right->bb_leftsib),
 885                         0, &lbp, XFS_INO_BTREE_REF)))
 886                 return error;
 887         left = XFS_BUF_TO_INOBT_BLOCK(lbp);
 888         if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
 889                 return error;
 890         /*
 891          * If it's full, it can't take another entry.
 892          */
 893         if (be16_to_cpu(left->bb_numrecs) == XFS_INOBT_BLOCK_MAXRECS(level, cur)) {
 894                 *stat = 0;
 895                 return 0;
 896         }
 897         nrec = be16_to_cpu(left->bb_numrecs) + 1;
 898         /*
 899          * If non-leaf, copy a key and a ptr to the left block.
 900          */
 901         if (level > 0) {
 902                 lkp = XFS_INOBT_KEY_ADDR(left, nrec, cur);
 903                 rkp = XFS_INOBT_KEY_ADDR(right, 1, cur);
 904                 *lkp = *rkp;
 905                 xfs_inobt_log_keys(cur, lbp, nrec, nrec);
 906                 lpp = XFS_INOBT_PTR_ADDR(left, nrec, cur);
 907                 rpp = XFS_INOBT_PTR_ADDR(right, 1, cur);
 908 #ifdef DEBUG
 909                 if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(*rpp), level)))
 910                         return error;
 911 #endif
 912                 *lpp = *rpp;
 913                 xfs_inobt_log_ptrs(cur, lbp, nrec, nrec);
 914         }
 915         /*
 916          * If leaf, copy a record to the left block.
 917          */
 918         else {
 919                 lrp = XFS_INOBT_REC_ADDR(left, nrec, cur);
 920                 rrp = XFS_INOBT_REC_ADDR(right, 1, cur);
 921                 *lrp = *rrp;
 922                 xfs_inobt_log_recs(cur, lbp, nrec, nrec);
 923         }
 924         /*
 925          * Bump and log left's numrecs, decrement and log right's numrecs.
 926          */
 927         be16_add_cpu(&left->bb_numrecs, 1);
 928         xfs_inobt_log_block(cur->bc_tp, lbp, XFS_BB_NUMRECS);
 929 #ifdef DEBUG
 930         if (level > 0)
 931                 xfs_btree_check_key(cur->bc_btnum, lkp - 1, lkp);
 932         else
 933                 xfs_btree_check_rec(cur->bc_btnum, lrp - 1, lrp);
 934 #endif
 935         be16_add_cpu(&right->bb_numrecs, -1);
 936         xfs_inobt_log_block(cur->bc_tp, rbp, XFS_BB_NUMRECS);
 937         /*
 938          * Slide the contents of right down one entry.
 939          */
 940         if (level > 0) {
 941 #ifdef DEBUG
 942                 for (i = 0; i < be16_to_cpu(right->bb_numrecs); i++) {
 943                         if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(rpp[i + 1]),
 944                                         level)))
 945                                 return error;
 946                 }
 947 #endif
 948                 memmove(rkp, rkp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rkp));
 949                 memmove(rpp, rpp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rpp));
 950                 xfs_inobt_log_keys(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
 951                 xfs_inobt_log_ptrs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
 952         } else {
 953                 memmove(rrp, rrp + 1, be16_to_cpu(right->bb_numrecs) * sizeof(*rrp));
 954                 xfs_inobt_log_recs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
 955                 key.ir_startino = rrp->ir_startino;
 956                 rkp = &key;
 957         }
 958         /*
 959          * Update the parent key values of right.
 960          */
 961         if ((error = xfs_btree_updkey(cur, (union xfs_btree_key *)rkp, level + 1)))
 962                 return error;
 963         /*
 964          * Slide the cursor value left one.
 965          */
 966         cur->bc_ptrs[level]--;
 967         *stat = 1;
 968         return 0;
 969 }
 970
 971 /*
 972  * Allocate a new root block, fill it in.
 973  */
 974 STATIC int                              /* error */
 975 xfs_inobt_newroot(
 976         xfs_btree_cur_t         *cur,   /* btree cursor */
 977         int                     *stat)  /* success/failure */
 978 {
 979         xfs_agi_t               *agi;   /* a.g. inode header */
 980         xfs_alloc_arg_t         args;   /* allocation argument structure */
 981         xfs_inobt_block_t       *block; /* one half of the old root block */
 982         xfs_buf_t               *bp;    /* buffer containing block */
 983         int                     error;  /* error return value */
 984         xfs_inobt_key_t         *kp;    /* btree key pointer */
 985         xfs_agblock_t           lbno;   /* left block number */
 986         xfs_buf_t               *lbp;   /* left buffer pointer */
 987         xfs_inobt_block_t       *left;  /* left btree block */
 988         xfs_buf_t               *nbp;   /* new (root) buffer */
 989         xfs_inobt_block_t       *new;   /* new (root) btree block */
 990         int                     nptr;   /* new value for key index, 1 or 2 */
 991         xfs_inobt_ptr_t         *pp;    /* btree address pointer */
 992         xfs_agblock_t           rbno;   /* right block number */
 993         xfs_buf_t               *rbp;   /* right buffer pointer */
 994         xfs_inobt_block_t       *right; /* right btree block */
 995         xfs_inobt_rec_t         *rp;    /* btree record pointer */
 996
 997         ASSERT(cur->bc_nlevels < XFS_IN_MAXLEVELS(cur->bc_mp));
 998
 999         /*
1000          * Get a block & a buffer.
1001          */
1002         agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
1003         args.tp = cur->bc_tp;
1004         args.mp = cur->bc_mp;
1005         args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno,
1006                 be32_to_cpu(agi->agi_root));
1007         args.mod = args.minleft = args.alignment = args.total = args.wasdel =
1008                 args.isfl = args.userdata = args.minalignslop = 0;
1009         args.minlen = args.maxlen = args.prod = 1;
1010         args.type = XFS_ALLOCTYPE_NEAR_BNO;
1011         if ((error = xfs_alloc_vextent(&args)))
1012                 return error;
1013         /*
1014          * None available, we fail.
1015          */
1016         if (args.fsbno == NULLFSBLOCK) {
1017                 *stat = 0;
1018                 return 0;
1019         }
1020         ASSERT(args.len == 1);
1021         nbp = xfs_btree_get_bufs(args.mp, args.tp, args.agno, args.agbno, 0);
1022         new = XFS_BUF_TO_INOBT_BLOCK(nbp);
1023         /*
1024          * Set the root data in the a.g. inode structure.
1025          */
1026         agi->agi_root = cpu_to_be32(args.agbno);
1027         be32_add_cpu(&agi->agi_level, 1);
1028         xfs_ialloc_log_agi(args.tp, cur->bc_private.a.agbp,
1029                 XFS_AGI_ROOT | XFS_AGI_LEVEL);
1030         /*
1031          * At the previous root level there are now two blocks: the old
1032          * root, and the new block generated when it was split.
1033          * We don't know which one the cursor is pointing at, so we
1034          * set up variables "left" and "right" for each case.
1035          */
1036         bp = cur->bc_bufs[cur->bc_nlevels - 1];
1037         block = XFS_BUF_TO_INOBT_BLOCK(bp);
1038 #ifdef DEBUG
1039         if ((error = xfs_btree_check_sblock(cur, block, cur->bc_nlevels - 1, bp)))
1040                 return error;
1041 #endif
1042         if (be32_to_cpu(block->bb_rightsib) != NULLAGBLOCK) {
1043                 /*
1044                  * Our block is left, pick up the right block.
1045                  */
1046                 lbp = bp;
1047                 lbno = XFS_DADDR_TO_AGBNO(args.mp, XFS_BUF_ADDR(lbp));
1048                 left = block;
1049                 rbno = be32_to_cpu(left->bb_rightsib);
1050                 if ((error = xfs_btree_read_bufs(args.mp, args.tp, args.agno,
1051                                 rbno, 0, &rbp, XFS_INO_BTREE_REF)))
1052                         return error;
1053                 bp = rbp;
1054                 right = XFS_BUF_TO_INOBT_BLOCK(rbp);
1055                 if ((error = xfs_btree_check_sblock(cur, right,
1056                                 cur->bc_nlevels - 1, rbp)))
1057                         return error;
1058                 nptr = 1;
1059         } else {
1060                 /*
1061                  * Our block is right, pick up the left block.
1062                  */
1063                 rbp = bp;
1064                 rbno = XFS_DADDR_TO_AGBNO(args.mp, XFS_BUF_ADDR(rbp));
1065                 right = block;
1066                 lbno = be32_to_cpu(right->bb_leftsib);
1067                 if ((error = xfs_btree_read_bufs(args.mp, args.tp, args.agno,
1068                                 lbno, 0, &lbp, XFS_INO_BTREE_REF)))
1069                         return error;
1070                 bp = lbp;
1071                 left = XFS_BUF_TO_INOBT_BLOCK(lbp);
1072                 if ((error = xfs_btree_check_sblock(cur, left,
1073                                 cur->bc_nlevels - 1, lbp)))
1074                         return error;
1075                 nptr = 2;
1076         }
1077         /*
1078          * Fill in the new block's btree header and log it.
1079          */
1080         new->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]);
1081         new->bb_level = cpu_to_be16(cur->bc_nlevels);
1082         new->bb_numrecs = cpu_to_be16(2);
1083         new->bb_leftsib = cpu_to_be32(NULLAGBLOCK);
1084         new->bb_rightsib = cpu_to_be32(NULLAGBLOCK);
1085         xfs_inobt_log_block(args.tp, nbp, XFS_BB_ALL_BITS);
1086         ASSERT(lbno != NULLAGBLOCK && rbno != NULLAGBLOCK);
1087         /*
1088          * Fill in the key data in the new root.
1089          */
1090         kp = XFS_INOBT_KEY_ADDR(new, 1, cur);
1091         if (be16_to_cpu(left->bb_level) > 0) {
1092                 kp[0] = *XFS_INOBT_KEY_ADDR(left, 1, cur);
1093                 kp[1] = *XFS_INOBT_KEY_ADDR(right, 1, cur);
1094         } else {
1095                 rp = XFS_INOBT_REC_ADDR(left, 1, cur);
1096                 kp[0].ir_startino = rp->ir_startino;
1097                 rp = XFS_INOBT_REC_ADDR(right, 1, cur);
1098                 kp[1].ir_startino = rp->ir_startino;
1099         }
1100         xfs_inobt_log_keys(cur, nbp, 1, 2);
1101         /*
1102          * Fill in the pointer data in the new root.
1103          */
1104         pp = XFS_INOBT_PTR_ADDR(new, 1, cur);
1105         pp[0] = cpu_to_be32(lbno);
1106         pp[1] = cpu_to_be32(rbno);
1107         xfs_inobt_log_ptrs(cur, nbp, 1, 2);
1108         /*
1109          * Fix up the cursor.
1110          */
1111         xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
1112         cur->bc_ptrs[cur->bc_nlevels] = nptr;
1113         cur->bc_nlevels++;
1114         *stat = 1;
1115         return 0;
1116 }
1117
1118 /*
1119  * Split cur/level block in half.
1120  * Return new block number and its first record (to be inserted into parent).
1121  */
1122 STATIC int                              /* error */
1123 xfs_inobt_split(
1124         xfs_btree_cur_t         *cur,   /* btree cursor */
1125         int                     level,  /* level to split */
1126         xfs_agblock_t           *bnop,  /* output: block number allocated */
1127         xfs_inobt_key_t         *keyp,  /* output: first key of new block */
1128         xfs_btree_cur_t         **curp, /* output: new cursor */
1129         int                     *stat)  /* success/failure */
1130 {
1131         xfs_alloc_arg_t         args;   /* allocation argument structure */
1132         int                     error;  /* error return value */
1133         int                     i;      /* loop index/record number */
1134         xfs_agblock_t           lbno;   /* left (current) block number */
1135         xfs_buf_t               *lbp;   /* buffer for left block */
1136         xfs_inobt_block_t       *left;  /* left (current) btree block */
1137         xfs_inobt_key_t         *lkp;   /* left btree key pointer */
1138         xfs_inobt_ptr_t         *lpp;   /* left btree address pointer */
1139         xfs_inobt_rec_t         *lrp;   /* left btree record pointer */
1140         xfs_buf_t               *rbp;   /* buffer for right block */
1141         xfs_inobt_block_t       *right; /* right (new) btree block */
1142         xfs_inobt_key_t         *rkp;   /* right btree key pointer */
1143         xfs_inobt_ptr_t         *rpp;   /* right btree address pointer */
1144         xfs_inobt_rec_t         *rrp;   /* right btree record pointer */
1145
1146         /*
1147          * Set up left block (current one).
1148          */
1149         lbp = cur->bc_bufs[level];
1150         args.tp = cur->bc_tp;
1151         args.mp = cur->bc_mp;
1152         lbno = XFS_DADDR_TO_AGBNO(args.mp, XFS_BUF_ADDR(lbp));
1153         /*
1154          * Allocate the new block.
1155          * If we can't do it, we're toast.  Give up.
1156          */
1157         args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, lbno);
1158         args.mod = args.minleft = args.alignment = args.total = args.wasdel =
1159                 args.isfl = args.userdata = args.minalignslop = 0;
1160         args.minlen = args.maxlen = args.prod = 1;
1161         args.type = XFS_ALLOCTYPE_NEAR_BNO;
1162         if ((error = xfs_alloc_vextent(&args)))
1163                 return error;
1164         if (args.fsbno == NULLFSBLOCK) {
1165                 *stat = 0;
1166                 return 0;
1167         }
1168         ASSERT(args.len == 1);
1169         rbp = xfs_btree_get_bufs(args.mp, args.tp, args.agno, args.agbno, 0);
1170         /*
1171          * Set up the new block as "right".
1172          */
1173         right = XFS_BUF_TO_INOBT_BLOCK(rbp);
1174         /*
1175          * "Left" is the current (according to the cursor) block.
1176          */
1177         left = XFS_BUF_TO_INOBT_BLOCK(lbp);
1178 #ifdef DEBUG
1179         if ((error = xfs_btree_check_sblock(cur, left, level, lbp)))
1180                 return error;
1181 #endif
1182         /*
1183          * Fill in the btree header for the new block.
1184          */
1185         right->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]);
1186         right->bb_level = left->bb_level;
1187         right->bb_numrecs = cpu_to_be16(be16_to_cpu(left->bb_numrecs) / 2);
1188         /*
1189          * Make sure that if there's an odd number of entries now, that
1190          * each new block will have the same number of entries.
1191          */
1192         if ((be16_to_cpu(left->bb_numrecs) & 1) &&
1193             cur->bc_ptrs[level] <= be16_to_cpu(right->bb_numrecs) + 1)
1194                 be16_add_cpu(&right->bb_numrecs, 1);
1195         i = be16_to_cpu(left->bb_numrecs) - be16_to_cpu(right->bb_numrecs) + 1;
1196         /*
1197          * For non-leaf blocks, copy keys and addresses over to the new block.
1198          */
1199         if (level > 0) {
1200                 lkp = XFS_INOBT_KEY_ADDR(left, i, cur);
1201                 lpp = XFS_INOBT_PTR_ADDR(left, i, cur);
1202                 rkp = XFS_INOBT_KEY_ADDR(right, 1, cur);
1203                 rpp = XFS_INOBT_PTR_ADDR(right, 1, cur);
1204 #ifdef DEBUG
1205                 for (i = 0; i < be16_to_cpu(right->bb_numrecs); i++) {
1206                         if ((error = xfs_btree_check_sptr(cur, be32_to_cpu(lpp[i]), level)))
1207                                 return error;
1208                 }
1209 #endif
1210                 memcpy(rkp, lkp, be16_to_cpu(right->bb_numrecs) * sizeof(*rkp));
1211                 memcpy(rpp, lpp, be16_to_cpu(right->bb_numrecs) * sizeof(*rpp));
1212                 xfs_inobt_log_keys(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
1213                 xfs_inobt_log_ptrs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
1214                 *keyp = *rkp;
1215         }
1216         /*
1217          * For leaf blocks, copy records over to the new block.
1218          */
1219         else {
1220                 lrp = XFS_INOBT_REC_ADDR(left, i, cur);
1221                 rrp = XFS_INOBT_REC_ADDR(right, 1, cur);
1222                 memcpy(rrp, lrp, be16_to_cpu(right->bb_numrecs) * sizeof(*rrp));
1223                 xfs_inobt_log_recs(cur, rbp, 1, be16_to_cpu(right->bb_numrecs));
1224                 keyp->ir_startino = rrp->ir_startino;
1225         }
1226         /*
1227          * Find the left block number by looking in the buffer.
1228          * Adjust numrecs, sibling pointers.
1229          */
1230         be16_add_cpu(&left->bb_numrecs, -(be16_to_cpu(right->bb_numrecs)));
1231         right->bb_rightsib = left->bb_rightsib;
1232         left->bb_rightsib = cpu_to_be32(args.agbno);
1233         right->bb_leftsib = cpu_to_be32(lbno);
1234         xfs_inobt_log_block(args.tp, rbp, XFS_BB_ALL_BITS);
1235         xfs_inobt_log_block(args.tp, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
1236         /*
1237          * If there's a block to the new block's right, make that block
1238          * point back to right instead of to left.
1239          */
1240         if (be32_to_cpu(right->bb_rightsib) != NULLAGBLOCK) {
1241                 xfs_inobt_block_t       *rrblock;       /* rr btree block */
1242                 xfs_buf_t               *rrbp;          /* buffer for rrblock */
1243
1244                 if ((error = xfs_btree_read_bufs(args.mp, args.tp, args.agno,
1245                                 be32_to_cpu(right->bb_rightsib), 0, &rrbp,
1246                                 XFS_INO_BTREE_REF)))
1247                         return error;
1248                 rrblock = XFS_BUF_TO_INOBT_BLOCK(rrbp);
1249                 if ((error = xfs_btree_check_sblock(cur, rrblock, level, rrbp)))
1250                         return error;
1251                 rrblock->bb_leftsib = cpu_to_be32(args.agbno);
1252                 xfs_inobt_log_block(args.tp, rrbp, XFS_BB_LEFTSIB);
1253         }
1254         /*
1255          * If the cursor is really in the right block, move it there.
1256          * If it's just pointing past the last entry in left, then we'll
1257          * insert there, so don't change anything in that case.
1258          */
1259         if (cur->bc_ptrs[level] > be16_to_cpu(left->bb_numrecs) + 1) {
1260                 xfs_btree_setbuf(cur, level, rbp);
1261                 cur->bc_ptrs[level] -= be16_to_cpu(left->bb_numrecs);
1262         }
1263         /*
1264          * If there are more levels, we'll need another cursor which refers
1265          * the right block, no matter where this cursor was.
1266          */
1267         if (level + 1 < cur->bc_nlevels) {
1268                 if ((error = xfs_btree_dup_cursor(cur, curp)))
1269                         return error;
1270                 (*curp)->bc_ptrs[level + 1]++;
1271         }
1272         *bnop = args.agbno;
1273         *stat = 1;
1274         return 0;
1275 }
1276
1277 /*
1278  * Externally visible routines.
1279  */
1280
1281 /*
1282  * Delete the record pointed to by cur.
1283  * The cursor refers to the place where the record was (could be inserted)
1284  * when the operation returns.
1285  */
1286 int                                     /* error */
1287 xfs_inobt_delete(
1288         xfs_btree_cur_t *cur,           /* btree cursor */
1289         int             *stat)          /* success/failure */
1290 {
1291         int             error;
1292         int             i;              /* result code */
1293         int             level;          /* btree level */
1294
1295         /*
1296          * Go up the tree, starting at leaf level.
1297          * If 2 is returned then a join was done; go to the next level.
1298          * Otherwise we are done.
1299          */
1300         for (level = 0, i = 2; i == 2; level++) {
1301                 if ((error = xfs_inobt_delrec(cur, level, &i)))
1302                         return error;
1303         }
1304         if (i == 0) {
1305                 for (level = 1; level < cur->bc_nlevels; level++) {
1306                         if (cur->bc_ptrs[level] == 0) {
1307                                 if ((error = xfs_btree_decrement(cur, level, &i)))
1308                                         return error;
1309                                 break;
1310                         }
1311                 }
1312         }
1313         *stat = i;
1314         return 0;
1315 }
1316
1317
1318 /*
1319  * Get the data from the pointed-to record.
1320  */
1321 int                                     /* error */
1322 xfs_inobt_get_rec(
1323         xfs_btree_cur_t         *cur,   /* btree cursor */
1324         xfs_agino_t             *ino,   /* output: starting inode of chunk */
1325         __int32_t               *fcnt,  /* output: number of free inodes */
1326         xfs_inofree_t           *free,  /* output: free inode mask */
1327         int                     *stat)  /* output: success/failure */
1328 {
1329         xfs_inobt_block_t       *block; /* btree block */
1330         xfs_buf_t               *bp;    /* buffer containing btree block */
1331 #ifdef DEBUG
1332         int                     error;  /* error return value */
1333 #endif
1334         int                     ptr;    /* record number */
1335         xfs_inobt_rec_t         *rec;   /* record data */
1336
1337         bp = cur->bc_bufs[0];
1338         ptr = cur->bc_ptrs[0];
1339         block = XFS_BUF_TO_INOBT_BLOCK(bp);
1340 #ifdef DEBUG
1341         if ((error = xfs_btree_check_sblock(cur, block, 0, bp)))
1342                 return error;
1343 #endif
1344         /*
1345          * Off the right end or left end, return failure.
1346          */
1347         if (ptr > be16_to_cpu(block->bb_numrecs) || ptr <= 0) {
1348                 *stat = 0;
1349                 return 0;
1350         }
1351         /*
1352          * Point to the record and extract its data.
1353          */
1354         rec = XFS_INOBT_REC_ADDR(block, ptr, cur);
1355         *ino = be32_to_cpu(rec->ir_startino);
1356         *fcnt = be32_to_cpu(rec->ir_freecount);
1357         *free = be64_to_cpu(rec->ir_free);
1358         *stat = 1;
1359         return 0;
1360 }
1361
1362 /*
1363  * Insert the current record at the point referenced by cur.
1364  * The cursor may be inconsistent on return if splits have been done.
1365  */
1366 int                                     /* error */
1367 xfs_inobt_insert(
1368         xfs_btree_cur_t *cur,           /* btree cursor */
1369         int             *stat)          /* success/failure */
1370 {
1371         int             error;          /* error return value */
1372         int             i;              /* result value, 0 for failure */
1373         int             level;          /* current level number in btree */
1374         xfs_agblock_t   nbno;           /* new block number (split result) */
1375         xfs_btree_cur_t *ncur;          /* new cursor (split result) */
1376         xfs_inobt_rec_t nrec;           /* record being inserted this level */
1377         xfs_btree_cur_t *pcur;          /* previous level's cursor */
1378
1379         level = 0;
1380         nbno = NULLAGBLOCK;
1381         nrec.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
1382         nrec.ir_freecount = cpu_to_be32(cur->bc_rec.i.ir_freecount);
1383         nrec.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
1384         ncur = NULL;
1385         pcur = cur;
1386         /*
1387          * Loop going up the tree, starting at the leaf level.
1388          * Stop when we don't get a split block, that must mean that
1389          * the insert is finished with this level.
1390          */
1391         do {
1392                 /*
1393                  * Insert nrec/nbno into this level of the tree.
1394                  * Note if we fail, nbno will be null.
1395                  */
1396                 if ((error = xfs_inobt_insrec(pcur, level++, &nbno, &nrec, &ncur,
1397                                 &i))) {
1398                         if (pcur != cur)
1399                                 xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
1400                         return error;
1401                 }
1402                 /*
1403                  * See if the cursor we just used is trash.
1404                  * Can't trash the caller's cursor, but otherwise we should
1405                  * if ncur is a new cursor or we're about to be done.
1406                  */
1407                 if (pcur != cur && (ncur || nbno == NULLAGBLOCK)) {
1408                         cur->bc_nlevels = pcur->bc_nlevels;
1409                         xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
1410                 }
1411                 /*
1412                  * If we got a new cursor, switch to it.
1413                  */
1414                 if (ncur) {
1415                         pcur = ncur;
1416                         ncur = NULL;
1417                 }
1418         } while (nbno != NULLAGBLOCK);
1419         *stat = i;
1420         return 0;
1421 }
1422
1423 STATIC struct xfs_btree_cur *
1424 xfs_inobt_dup_cursor(
1425         struct xfs_btree_cur    *cur)
1426 {
1427         return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
1428                         cur->bc_private.a.agbp, cur->bc_private.a.agno);
1429 }
1430
1431 STATIC int
1432 xfs_inobt_get_maxrecs(
1433         struct xfs_btree_cur    *cur,
1434         int                     level)
1435 {
1436         return cur->bc_mp->m_inobt_mxr[level != 0];
1437 }
1438
1439 STATIC void
1440 xfs_inobt_init_key_from_rec(
1441         union xfs_btree_key     *key,
1442         union xfs_btree_rec     *rec)
1443 {
1444         key->inobt.ir_startino = rec->inobt.ir_startino;
1445 }
1446
1447 /*
1448  * intial value of ptr for lookup
1449  */
1450 STATIC void
1451 xfs_inobt_init_ptr_from_cur(
1452         struct xfs_btree_cur    *cur,
1453         union xfs_btree_ptr     *ptr)
1454 {
1455         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
1456
1457         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
1458
1459         ptr->s = agi->agi_root;
1460 }
1461
1462 STATIC __int64_t
1463 xfs_inobt_key_diff(
1464         struct xfs_btree_cur    *cur,
1465         union xfs_btree_key     *key)
1466 {
1467         return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
1468                           cur->bc_rec.i.ir_startino;
1469 }
1470
1471 #ifdef XFS_BTREE_TRACE
1472 ktrace_t        *xfs_inobt_trace_buf;
1473
1474 STATIC void
1475 xfs_inobt_trace_enter(
1476         struct xfs_btree_cur    *cur,
1477         const char              *func,
1478         char                    *s,
1479         int                     type,
1480         int                     line,
1481         __psunsigned_t          a0,
1482         __psunsigned_t          a1,
1483         __psunsigned_t          a2,
1484         __psunsigned_t          a3,
1485         __psunsigned_t          a4,
1486         __psunsigned_t          a5,
1487         __psunsigned_t          a6,
1488         __psunsigned_t          a7,
1489         __psunsigned_t          a8,
1490         __psunsigned_t          a9,
1491         __psunsigned_t          a10)
1492 {
1493         ktrace_enter(xfs_inobt_trace_buf, (void *)(__psint_t)type,
1494                 (void *)func, (void *)s, NULL, (void *)cur,
1495                 (void *)a0, (void *)a1, (void *)a2, (void *)a3,
1496                 (void *)a4, (void *)a5, (void *)a6, (void *)a7,
1497                 (void *)a8, (void *)a9, (void *)a10);
1498 }
1499
1500 STATIC void
1501 xfs_inobt_trace_cursor(
1502         struct xfs_btree_cur    *cur,
1503         __uint32_t              *s0,
1504         __uint64_t              *l0,
1505         __uint64_t              *l1)
1506 {
1507         *s0 = cur->bc_private.a.agno;
1508         *l0 = cur->bc_rec.i.ir_startino;
1509         *l1 = cur->bc_rec.i.ir_free;
1510 }
1511
1512 STATIC void
1513 xfs_inobt_trace_key(
1514         struct xfs_btree_cur    *cur,
1515         union xfs_btree_key     *key,
1516         __uint64_t              *l0,
1517         __uint64_t              *l1)
1518 {
1519         *l0 = be32_to_cpu(key->inobt.ir_startino);
1520         *l1 = 0;
1521 }
1522
1523 STATIC void
1524 xfs_inobt_trace_record(
1525         struct xfs_btree_cur    *cur,
1526         union xfs_btree_rec     *rec,
1527         __uint64_t              *l0,
1528         __uint64_t              *l1,
1529         __uint64_t              *l2)
1530 {
1531         *l0 = be32_to_cpu(rec->inobt.ir_startino);
1532         *l1 = be32_to_cpu(rec->inobt.ir_freecount);
1533         *l2 = be64_to_cpu(rec->inobt.ir_free);
1534 }
1535 #endif /* XFS_BTREE_TRACE */
1536
1537 static const struct xfs_btree_ops xfs_inobt_ops = {
1538         .rec_len                = sizeof(xfs_inobt_rec_t),
1539         .key_len                = sizeof(xfs_inobt_key_t),
1540
1541         .dup_cursor             = xfs_inobt_dup_cursor,
1542         .get_maxrecs            = xfs_inobt_get_maxrecs,
1543         .init_key_from_rec      = xfs_inobt_init_key_from_rec,
1544         .init_ptr_from_cur      = xfs_inobt_init_ptr_from_cur,
1545         .key_diff               = xfs_inobt_key_diff,
1546
1547 #ifdef XFS_BTREE_TRACE
1548         .trace_enter            = xfs_inobt_trace_enter,
1549         .trace_cursor           = xfs_inobt_trace_cursor,
1550         .trace_key              = xfs_inobt_trace_key,
1551         .trace_record           = xfs_inobt_trace_record,
1552 #endif
1553 };
1554
1555 /*
1556  * Allocate a new inode btree cursor.
1557  */
1558 struct xfs_btree_cur *                          /* new inode btree cursor */
1559 xfs_inobt_init_cursor(
1560         struct xfs_mount        *mp,            /* file system mount point */
1561         struct xfs_trans        *tp,            /* transaction pointer */
1562         struct xfs_buf          *agbp,          /* buffer for agi structure */
1563         xfs_agnumber_t          agno)           /* allocation group number */
1564 {
1565         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
1566         struct xfs_btree_cur    *cur;
1567
1568         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
1569
1570         cur->bc_tp = tp;
1571         cur->bc_mp = mp;
1572         cur->bc_nlevels = be32_to_cpu(agi->agi_level);
1573         cur->bc_btnum = XFS_BTNUM_INO;
1574         cur->bc_blocklog = mp->m_sb.sb_blocklog;
1575
1576         cur->bc_ops = &xfs_inobt_ops;
1577
1578         cur->bc_private.a.agbp = agbp;
1579         cur->bc_private.a.agno = agno;
1580
1581         return cur;
1582 }