fs/xfs/xfs_bmap_btree.c

   1 /*
   2  * Copyright (c) 2000-2003,2005 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_inode_item.h"
  38 #include "xfs_alloc.h"
  39 #include "xfs_btree.h"
  40 #include "xfs_btree_trace.h"
  41 #include "xfs_ialloc.h"
  42 #include "xfs_itable.h"
  43 #include "xfs_bmap.h"
  44 #include "xfs_error.h"
  45 #include "xfs_quota.h"
  46
  47 /*
  48  * Determine the extent state.
  49  */
  50 /* ARGSUSED */
  51 STATIC xfs_exntst_t
  52 xfs_extent_state(
  53         xfs_filblks_t           blks,
  54         int                     extent_flag)
  55 {
  56         if (extent_flag) {
  57                 ASSERT(blks != 0);      /* saved for DMIG */
  58                 return XFS_EXT_UNWRITTEN;
  59         }
  60         return XFS_EXT_NORM;
  61 }
  62
  63 /*
  64  * Convert on-disk form of btree root to in-memory form.
  65  */
  66 void
  67 xfs_bmdr_to_bmbt(
  68         struct xfs_mount        *mp,
  69         xfs_bmdr_block_t        *dblock,
  70         int                     dblocklen,
  71         struct xfs_btree_block  *rblock,
  72         int                     rblocklen)
  73 {
  74         int                     dmxr;
  75         xfs_bmbt_key_t          *fkp;
  76         __be64                  *fpp;
  77         xfs_bmbt_key_t          *tkp;
  78         __be64                  *tpp;
  79
  80         rblock->bb_magic = cpu_to_be32(XFS_BMAP_MAGIC);
  81         rblock->bb_level = dblock->bb_level;
  82         ASSERT(be16_to_cpu(rblock->bb_level) > 0);
  83         rblock->bb_numrecs = dblock->bb_numrecs;
  84         rblock->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO);
  85         rblock->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO);
  86         dmxr = xfs_bmdr_maxrecs(mp, dblocklen, 0);
  87         fkp = XFS_BMDR_KEY_ADDR(dblock, 1);
  88         tkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
  89         fpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
  90         tpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
  91         dmxr = be16_to_cpu(dblock->bb_numrecs);
  92         memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
  93         memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
  94 }
  95
  96 /*
  97  * Convert a compressed bmap extent record to an uncompressed form.
  98  * This code must be in sync with the routines xfs_bmbt_get_startoff,
  99  * xfs_bmbt_get_startblock, xfs_bmbt_get_blockcount and xfs_bmbt_get_state.
 100  */
 101 STATIC void
 102 __xfs_bmbt_get_all(
 103                 __uint64_t l0,
 104                 __uint64_t l1,
 105                 xfs_bmbt_irec_t *s)
 106 {
 107         int     ext_flag;
 108         xfs_exntst_t st;
 109
 110         ext_flag = (int)(l0 >> (64 - BMBT_EXNTFLAG_BITLEN));
 111         s->br_startoff = ((xfs_fileoff_t)l0 &
 112                            xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
 113 #if XFS_BIG_BLKNOS
 114         s->br_startblock = (((xfs_fsblock_t)l0 & xfs_mask64lo(9)) << 43) |
 115                            (((xfs_fsblock_t)l1) >> 21);
 116 #else
 117 #ifdef DEBUG
 118         {
 119                 xfs_dfsbno_t    b;
 120
 121                 b = (((xfs_dfsbno_t)l0 & xfs_mask64lo(9)) << 43) |
 122                     (((xfs_dfsbno_t)l1) >> 21);
 123                 ASSERT((b >> 32) == 0 || isnulldstartblock(b));
 124                 s->br_startblock = (xfs_fsblock_t)b;
 125         }
 126 #else   /* !DEBUG */
 127         s->br_startblock = (xfs_fsblock_t)(((xfs_dfsbno_t)l1) >> 21);
 128 #endif  /* DEBUG */
 129 #endif  /* XFS_BIG_BLKNOS */
 130         s->br_blockcount = (xfs_filblks_t)(l1 & xfs_mask64lo(21));
 131         /* This is xfs_extent_state() in-line */
 132         if (ext_flag) {
 133                 ASSERT(s->br_blockcount != 0);  /* saved for DMIG */
 134                 st = XFS_EXT_UNWRITTEN;
 135         } else
 136                 st = XFS_EXT_NORM;
 137         s->br_state = st;
 138 }
 139
 140 void
 141 xfs_bmbt_get_all(
 142         xfs_bmbt_rec_host_t *r,
 143         xfs_bmbt_irec_t *s)
 144 {
 145         __xfs_bmbt_get_all(r->l0, r->l1, s);
 146 }
 147
 148 /*
 149  * Extract the blockcount field from an in memory bmap extent record.
 150  */
 151 xfs_filblks_t
 152 xfs_bmbt_get_blockcount(
 153         xfs_bmbt_rec_host_t     *r)
 154 {
 155         return (xfs_filblks_t)(r->l1 & xfs_mask64lo(21));
 156 }
 157
 158 /*
 159  * Extract the startblock field from an in memory bmap extent record.
 160  */
 161 xfs_fsblock_t
 162 xfs_bmbt_get_startblock(
 163         xfs_bmbt_rec_host_t     *r)
 164 {
 165 #if XFS_BIG_BLKNOS
 166         return (((xfs_fsblock_t)r->l0 & xfs_mask64lo(9)) << 43) |
 167                (((xfs_fsblock_t)r->l1) >> 21);
 168 #else
 169 #ifdef DEBUG
 170         xfs_dfsbno_t    b;
 171
 172         b = (((xfs_dfsbno_t)r->l0 & xfs_mask64lo(9)) << 43) |
 173             (((xfs_dfsbno_t)r->l1) >> 21);
 174         ASSERT((b >> 32) == 0 || isnulldstartblock(b));
 175         return (xfs_fsblock_t)b;
 176 #else   /* !DEBUG */
 177         return (xfs_fsblock_t)(((xfs_dfsbno_t)r->l1) >> 21);
 178 #endif  /* DEBUG */
 179 #endif  /* XFS_BIG_BLKNOS */
 180 }
 181
 182 /*
 183  * Extract the startoff field from an in memory bmap extent record.
 184  */
 185 xfs_fileoff_t
 186 xfs_bmbt_get_startoff(
 187         xfs_bmbt_rec_host_t     *r)
 188 {
 189         return ((xfs_fileoff_t)r->l0 &
 190                  xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
 191 }
 192
 193 xfs_exntst_t
 194 xfs_bmbt_get_state(
 195         xfs_bmbt_rec_host_t     *r)
 196 {
 197         int     ext_flag;
 198
 199         ext_flag = (int)((r->l0) >> (64 - BMBT_EXNTFLAG_BITLEN));
 200         return xfs_extent_state(xfs_bmbt_get_blockcount(r),
 201                                 ext_flag);
 202 }
 203
 204 /*
 205  * Extract the blockcount field from an on disk bmap extent record.
 206  */
 207 xfs_filblks_t
 208 xfs_bmbt_disk_get_blockcount(
 209         xfs_bmbt_rec_t  *r)
 210 {
 211         return (xfs_filblks_t)(be64_to_cpu(r->l1) & xfs_mask64lo(21));
 212 }
 213
 214 /*
 215  * Extract the startoff field from a disk format bmap extent record.
 216  */
 217 xfs_fileoff_t
 218 xfs_bmbt_disk_get_startoff(
 219         xfs_bmbt_rec_t  *r)
 220 {
 221         return ((xfs_fileoff_t)be64_to_cpu(r->l0) &
 222                  xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN)) >> 9;
 223 }
 224
 225
 226 /*
 227  * Set all the fields in a bmap extent record from the arguments.
 228  */
 229 void
 230 xfs_bmbt_set_allf(
 231         xfs_bmbt_rec_host_t     *r,
 232         xfs_fileoff_t           startoff,
 233         xfs_fsblock_t           startblock,
 234         xfs_filblks_t           blockcount,
 235         xfs_exntst_t            state)
 236 {
 237         int             extent_flag = (state == XFS_EXT_NORM) ? 0 : 1;
 238
 239         ASSERT(state == XFS_EXT_NORM || state == XFS_EXT_UNWRITTEN);
 240         ASSERT((startoff & xfs_mask64hi(64-BMBT_STARTOFF_BITLEN)) == 0);
 241         ASSERT((blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)) == 0);
 242
 243 #if XFS_BIG_BLKNOS
 244         ASSERT((startblock & xfs_mask64hi(64-BMBT_STARTBLOCK_BITLEN)) == 0);
 245
 246         r->l0 = ((xfs_bmbt_rec_base_t)extent_flag << 63) |
 247                 ((xfs_bmbt_rec_base_t)startoff << 9) |
 248                 ((xfs_bmbt_rec_base_t)startblock >> 43);
 249         r->l1 = ((xfs_bmbt_rec_base_t)startblock << 21) |
 250                 ((xfs_bmbt_rec_base_t)blockcount &
 251                 (xfs_bmbt_rec_base_t)xfs_mask64lo(21));
 252 #else   /* !XFS_BIG_BLKNOS */
 253         if (isnullstartblock(startblock)) {
 254                 r->l0 = ((xfs_bmbt_rec_base_t)extent_flag << 63) |
 255                         ((xfs_bmbt_rec_base_t)startoff << 9) |
 256                          (xfs_bmbt_rec_base_t)xfs_mask64lo(9);
 257                 r->l1 = xfs_mask64hi(11) |
 258                           ((xfs_bmbt_rec_base_t)startblock << 21) |
 259                           ((xfs_bmbt_rec_base_t)blockcount &
 260                            (xfs_bmbt_rec_base_t)xfs_mask64lo(21));
 261         } else {
 262                 r->l0 = ((xfs_bmbt_rec_base_t)extent_flag << 63) |
 263                         ((xfs_bmbt_rec_base_t)startoff << 9);
 264                 r->l1 = ((xfs_bmbt_rec_base_t)startblock << 21) |
 265                          ((xfs_bmbt_rec_base_t)blockcount &
 266                          (xfs_bmbt_rec_base_t)xfs_mask64lo(21));
 267         }
 268 #endif  /* XFS_BIG_BLKNOS */
 269 }
 270
 271 /*
 272  * Set all the fields in a bmap extent record from the uncompressed form.
 273  */
 274 void
 275 xfs_bmbt_set_all(
 276         xfs_bmbt_rec_host_t *r,
 277         xfs_bmbt_irec_t *s)
 278 {
 279         xfs_bmbt_set_allf(r, s->br_startoff, s->br_startblock,
 280                              s->br_blockcount, s->br_state);
 281 }
 282
 283
 284 /*
 285  * Set all the fields in a disk format bmap extent record from the arguments.
 286  */
 287 void
 288 xfs_bmbt_disk_set_allf(
 289         xfs_bmbt_rec_t          *r,
 290         xfs_fileoff_t           startoff,
 291         xfs_fsblock_t           startblock,
 292         xfs_filblks_t           blockcount,
 293         xfs_exntst_t            state)
 294 {
 295         int                     extent_flag = (state == XFS_EXT_NORM) ? 0 : 1;
 296
 297         ASSERT(state == XFS_EXT_NORM || state == XFS_EXT_UNWRITTEN);
 298         ASSERT((startoff & xfs_mask64hi(64-BMBT_STARTOFF_BITLEN)) == 0);
 299         ASSERT((blockcount & xfs_mask64hi(64-BMBT_BLOCKCOUNT_BITLEN)) == 0);
 300
 301 #if XFS_BIG_BLKNOS
 302         ASSERT((startblock & xfs_mask64hi(64-BMBT_STARTBLOCK_BITLEN)) == 0);
 303
 304         r->l0 = cpu_to_be64(
 305                 ((xfs_bmbt_rec_base_t)extent_flag << 63) |
 306                  ((xfs_bmbt_rec_base_t)startoff << 9) |
 307                  ((xfs_bmbt_rec_base_t)startblock >> 43));
 308         r->l1 = cpu_to_be64(
 309                 ((xfs_bmbt_rec_base_t)startblock << 21) |
 310                  ((xfs_bmbt_rec_base_t)blockcount &
 311                   (xfs_bmbt_rec_base_t)xfs_mask64lo(21)));
 312 #else   /* !XFS_BIG_BLKNOS */
 313         if (isnullstartblock(startblock)) {
 314                 r->l0 = cpu_to_be64(
 315                         ((xfs_bmbt_rec_base_t)extent_flag << 63) |
 316                          ((xfs_bmbt_rec_base_t)startoff << 9) |
 317                           (xfs_bmbt_rec_base_t)xfs_mask64lo(9));
 318                 r->l1 = cpu_to_be64(xfs_mask64hi(11) |
 319                           ((xfs_bmbt_rec_base_t)startblock << 21) |
 320                           ((xfs_bmbt_rec_base_t)blockcount &
 321                            (xfs_bmbt_rec_base_t)xfs_mask64lo(21)));
 322         } else {
 323                 r->l0 = cpu_to_be64(
 324                         ((xfs_bmbt_rec_base_t)extent_flag << 63) |
 325                          ((xfs_bmbt_rec_base_t)startoff << 9));
 326                 r->l1 = cpu_to_be64(
 327                         ((xfs_bmbt_rec_base_t)startblock << 21) |
 328                          ((xfs_bmbt_rec_base_t)blockcount &
 329                           (xfs_bmbt_rec_base_t)xfs_mask64lo(21)));
 330         }
 331 #endif  /* XFS_BIG_BLKNOS */
 332 }
 333
 334 /*
 335  * Set all the fields in a bmap extent record from the uncompressed form.
 336  */
 337 void
 338 xfs_bmbt_disk_set_all(
 339         xfs_bmbt_rec_t  *r,
 340         xfs_bmbt_irec_t *s)
 341 {
 342         xfs_bmbt_disk_set_allf(r, s->br_startoff, s->br_startblock,
 343                                   s->br_blockcount, s->br_state);
 344 }
 345
 346 /*
 347  * Set the blockcount field in a bmap extent record.
 348  */
 349 void
 350 xfs_bmbt_set_blockcount(
 351         xfs_bmbt_rec_host_t *r,
 352         xfs_filblks_t   v)
 353 {
 354         ASSERT((v & xfs_mask64hi(43)) == 0);
 355         r->l1 = (r->l1 & (xfs_bmbt_rec_base_t)xfs_mask64hi(43)) |
 356                   (xfs_bmbt_rec_base_t)(v & xfs_mask64lo(21));
 357 }
 358
 359 /*
 360  * Set the startblock field in a bmap extent record.
 361  */
 362 void
 363 xfs_bmbt_set_startblock(
 364         xfs_bmbt_rec_host_t *r,
 365         xfs_fsblock_t   v)
 366 {
 367 #if XFS_BIG_BLKNOS
 368         ASSERT((v & xfs_mask64hi(12)) == 0);
 369         r->l0 = (r->l0 & (xfs_bmbt_rec_base_t)xfs_mask64hi(55)) |
 370                   (xfs_bmbt_rec_base_t)(v >> 43);
 371         r->l1 = (r->l1 & (xfs_bmbt_rec_base_t)xfs_mask64lo(21)) |
 372                   (xfs_bmbt_rec_base_t)(v << 21);
 373 #else   /* !XFS_BIG_BLKNOS */
 374         if (isnullstartblock(v)) {
 375                 r->l0 |= (xfs_bmbt_rec_base_t)xfs_mask64lo(9);
 376                 r->l1 = (xfs_bmbt_rec_base_t)xfs_mask64hi(11) |
 377                           ((xfs_bmbt_rec_base_t)v << 21) |
 378                           (r->l1 & (xfs_bmbt_rec_base_t)xfs_mask64lo(21));
 379         } else {
 380                 r->l0 &= ~(xfs_bmbt_rec_base_t)xfs_mask64lo(9);
 381                 r->l1 = ((xfs_bmbt_rec_base_t)v << 21) |
 382                           (r->l1 & (xfs_bmbt_rec_base_t)xfs_mask64lo(21));
 383         }
 384 #endif  /* XFS_BIG_BLKNOS */
 385 }
 386
 387 /*
 388  * Set the startoff field in a bmap extent record.
 389  */
 390 void
 391 xfs_bmbt_set_startoff(
 392         xfs_bmbt_rec_host_t *r,
 393         xfs_fileoff_t   v)
 394 {
 395         ASSERT((v & xfs_mask64hi(9)) == 0);
 396         r->l0 = (r->l0 & (xfs_bmbt_rec_base_t) xfs_mask64hi(1)) |
 397                 ((xfs_bmbt_rec_base_t)v << 9) |
 398                   (r->l0 & (xfs_bmbt_rec_base_t)xfs_mask64lo(9));
 399 }
 400
 401 /*
 402  * Set the extent state field in a bmap extent record.
 403  */
 404 void
 405 xfs_bmbt_set_state(
 406         xfs_bmbt_rec_host_t *r,
 407         xfs_exntst_t    v)
 408 {
 409         ASSERT(v == XFS_EXT_NORM || v == XFS_EXT_UNWRITTEN);
 410         if (v == XFS_EXT_NORM)
 411                 r->l0 &= xfs_mask64lo(64 - BMBT_EXNTFLAG_BITLEN);
 412         else
 413                 r->l0 |= xfs_mask64hi(BMBT_EXNTFLAG_BITLEN);
 414 }
 415
 416 /*
 417  * Convert in-memory form of btree root to on-disk form.
 418  */
 419 void
 420 xfs_bmbt_to_bmdr(
 421         struct xfs_mount        *mp,
 422         struct xfs_btree_block  *rblock,
 423         int                     rblocklen,
 424         xfs_bmdr_block_t        *dblock,
 425         int                     dblocklen)
 426 {
 427         int                     dmxr;
 428         xfs_bmbt_key_t          *fkp;
 429         __be64                  *fpp;
 430         xfs_bmbt_key_t          *tkp;
 431         __be64                  *tpp;
 432
 433         ASSERT(be32_to_cpu(rblock->bb_magic) == XFS_BMAP_MAGIC);
 434         ASSERT(be64_to_cpu(rblock->bb_u.l.bb_leftsib) == NULLDFSBNO);
 435         ASSERT(be64_to_cpu(rblock->bb_u.l.bb_rightsib) == NULLDFSBNO);
 436         ASSERT(be16_to_cpu(rblock->bb_level) > 0);
 437         dblock->bb_level = rblock->bb_level;
 438         dblock->bb_numrecs = rblock->bb_numrecs;
 439         dmxr = xfs_bmdr_maxrecs(mp, dblocklen, 0);
 440         fkp = XFS_BMBT_KEY_ADDR(mp, rblock, 1);
 441         tkp = XFS_BMDR_KEY_ADDR(dblock, 1);
 442         fpp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, rblocklen);
 443         tpp = XFS_BMDR_PTR_ADDR(dblock, 1, dmxr);
 444         dmxr = be16_to_cpu(dblock->bb_numrecs);
 445         memcpy(tkp, fkp, sizeof(*fkp) * dmxr);
 446         memcpy(tpp, fpp, sizeof(*fpp) * dmxr);
 447 }
 448
 449 /*
 450  * Check extent records, which have just been read, for
 451  * any bit in the extent flag field. ASSERT on debug
 452  * kernels, as this condition should not occur.
 453  * Return an error condition (1) if any flags found,
 454  * otherwise return 0.
 455  */
 456
 457 int
 458 xfs_check_nostate_extents(
 459         xfs_ifork_t             *ifp,
 460         xfs_extnum_t            idx,
 461         xfs_extnum_t            num)
 462 {
 463         for (; num > 0; num--, idx++) {
 464                 xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, idx);
 465                 if ((ep->l0 >>
 466                      (64 - BMBT_EXNTFLAG_BITLEN)) != 0) {
 467                         ASSERT(0);
 468                         return 1;
 469                 }
 470         }
 471         return 0;
 472 }
 473
 474
 475 STATIC struct xfs_btree_cur *
 476 xfs_bmbt_dup_cursor(
 477         struct xfs_btree_cur    *cur)
 478 {
 479         struct xfs_btree_cur    *new;
 480
 481         new = xfs_bmbt_init_cursor(cur->bc_mp, cur->bc_tp,
 482                         cur->bc_private.b.ip, cur->bc_private.b.whichfork);
 483
 484         /*
 485          * Copy the firstblock, flist, and flags values,
 486          * since init cursor doesn't get them.
 487          */
 488         new->bc_private.b.firstblock = cur->bc_private.b.firstblock;
 489         new->bc_private.b.flist = cur->bc_private.b.flist;
 490         new->bc_private.b.flags = cur->bc_private.b.flags;
 491
 492         return new;
 493 }
 494
 495 STATIC void
 496 xfs_bmbt_update_cursor(
 497         struct xfs_btree_cur    *src,
 498         struct xfs_btree_cur    *dst)
 499 {
 500         ASSERT((dst->bc_private.b.firstblock != NULLFSBLOCK) ||
 501                (dst->bc_private.b.ip->i_d.di_flags & XFS_DIFLAG_REALTIME));
 502         ASSERT(dst->bc_private.b.flist == src->bc_private.b.flist);
 503
 504         dst->bc_private.b.allocated += src->bc_private.b.allocated;
 505         dst->bc_private.b.firstblock = src->bc_private.b.firstblock;
 506
 507         src->bc_private.b.allocated = 0;
 508 }
 509
 510 STATIC int
 511 xfs_bmbt_alloc_block(
 512         struct xfs_btree_cur    *cur,
 513         union xfs_btree_ptr     *start,
 514         union xfs_btree_ptr     *new,
 515         int                     length,
 516         int                     *stat)
 517 {
 518         xfs_alloc_arg_t         args;           /* block allocation args */
 519         int                     error;          /* error return value */
 520
 521         memset(&args, 0, sizeof(args));
 522         args.tp = cur->bc_tp;
 523         args.mp = cur->bc_mp;
 524         args.fsbno = cur->bc_private.b.firstblock;
 525         args.firstblock = args.fsbno;
 526
 527         if (args.fsbno == NULLFSBLOCK) {
 528                 args.fsbno = be64_to_cpu(start->l);
 529                 args.type = XFS_ALLOCTYPE_START_BNO;
 530                 /*
 531                  * Make sure there is sufficient room left in the AG to
 532                  * complete a full tree split for an extent insert.  If
 533                  * we are converting the middle part of an extent then
 534                  * we may need space for two tree splits.
 535                  *
 536                  * We are relying on the caller to make the correct block
 537                  * reservation for this operation to succeed.  If the
 538                  * reservation amount is insufficient then we may fail a
 539                  * block allocation here and corrupt the filesystem.
 540                  */
 541                 args.minleft = xfs_trans_get_block_res(args.tp);
 542         } else if (cur->bc_private.b.flist->xbf_low) {
 543                 args.type = XFS_ALLOCTYPE_START_BNO;
 544         } else {
 545                 args.type = XFS_ALLOCTYPE_NEAR_BNO;
 546         }
 547
 548         args.minlen = args.maxlen = args.prod = 1;
 549         args.wasdel = cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL;
 550         if (!args.wasdel && xfs_trans_get_block_res(args.tp) == 0) {
 551                 error = XFS_ERROR(ENOSPC);
 552                 goto error0;
 553         }
 554         error = xfs_alloc_vextent(&args);
 555         if (error)
 556                 goto error0;
 557
 558         if (args.fsbno == NULLFSBLOCK && args.minleft) {
 559                 /*
 560                  * Could not find an AG with enough free space to satisfy
 561                  * a full btree split.  Try again without minleft and if
 562                  * successful activate the lowspace algorithm.
 563                  */
 564                 args.fsbno = 0;
 565                 args.type = XFS_ALLOCTYPE_FIRST_AG;
 566                 args.minleft = 0;
 567                 error = xfs_alloc_vextent(&args);
 568                 if (error)
 569                         goto error0;
 570                 cur->bc_private.b.flist->xbf_low = 1;
 571         }
 572         if (args.fsbno == NULLFSBLOCK) {
 573                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 574                 *stat = 0;
 575                 return 0;
 576         }
 577         ASSERT(args.len == 1);
 578         cur->bc_private.b.firstblock = args.fsbno;
 579         cur->bc_private.b.allocated++;
 580         cur->bc_private.b.ip->i_d.di_nblocks++;
 581         xfs_trans_log_inode(args.tp, cur->bc_private.b.ip, XFS_ILOG_CORE);
 582         xfs_trans_mod_dquot_byino(args.tp, cur->bc_private.b.ip,
 583                         XFS_TRANS_DQ_BCOUNT, 1L);
 584
 585         new->l = cpu_to_be64(args.fsbno);
 586
 587         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 588         *stat = 1;
 589         return 0;
 590
 591  error0:
 592         XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
 593         return error;
 594 }
 595
 596 STATIC int
 597 xfs_bmbt_free_block(
 598         struct xfs_btree_cur    *cur,
 599         struct xfs_buf          *bp)
 600 {
 601         struct xfs_mount        *mp = cur->bc_mp;
 602         struct xfs_inode        *ip = cur->bc_private.b.ip;
 603         struct xfs_trans        *tp = cur->bc_tp;
 604         xfs_fsblock_t           fsbno = XFS_DADDR_TO_FSB(mp, XFS_BUF_ADDR(bp));
 605
 606         xfs_bmap_add_free(fsbno, 1, cur->bc_private.b.flist, mp);
 607         ip->i_d.di_nblocks--;
 608
 609         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 610         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
 611         xfs_trans_binval(tp, bp);
 612         return 0;
 613 }
 614
 615 STATIC int
 616 xfs_bmbt_get_minrecs(
 617         struct xfs_btree_cur    *cur,
 618         int                     level)
 619 {
 620         if (level == cur->bc_nlevels - 1) {
 621                 struct xfs_ifork        *ifp;
 622
 623                 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip,
 624                                     cur->bc_private.b.whichfork);
 625
 626                 return xfs_bmbt_maxrecs(cur->bc_mp,
 627                                         ifp->if_broot_bytes, level == 0) / 2;
 628         }
 629
 630         return cur->bc_mp->m_bmap_dmnr[level != 0];
 631 }
 632
 633 int
 634 xfs_bmbt_get_maxrecs(
 635         struct xfs_btree_cur    *cur,
 636         int                     level)
 637 {
 638         if (level == cur->bc_nlevels - 1) {
 639                 struct xfs_ifork        *ifp;
 640
 641                 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip,
 642                                     cur->bc_private.b.whichfork);
 643
 644                 return xfs_bmbt_maxrecs(cur->bc_mp,
 645                                         ifp->if_broot_bytes, level == 0);
 646         }
 647
 648         return cur->bc_mp->m_bmap_dmxr[level != 0];
 649
 650 }
 651
 652 /*
 653  * Get the maximum records we could store in the on-disk format.
 654  *
 655  * For non-root nodes this is equivalent to xfs_bmbt_get_maxrecs, but
 656  * for the root node this checks the available space in the dinode fork
 657  * so that we can resize the in-memory buffer to match it.  After a
 658  * resize to the maximum size this function returns the same value
 659  * as xfs_bmbt_get_maxrecs for the root node, too.
 660  */
 661 STATIC int
 662 xfs_bmbt_get_dmaxrecs(
 663         struct xfs_btree_cur    *cur,
 664         int                     level)
 665 {
 666         if (level != cur->bc_nlevels - 1)
 667                 return cur->bc_mp->m_bmap_dmxr[level != 0];
 668         return xfs_bmdr_maxrecs(cur->bc_mp, cur->bc_private.b.forksize,
 669                                 level == 0);
 670 }
 671
 672 STATIC void
 673 xfs_bmbt_init_key_from_rec(
 674         union xfs_btree_key     *key,
 675         union xfs_btree_rec     *rec)
 676 {
 677         key->bmbt.br_startoff =
 678                 cpu_to_be64(xfs_bmbt_disk_get_startoff(&rec->bmbt));
 679 }
 680
 681 STATIC void
 682 xfs_bmbt_init_rec_from_key(
 683         union xfs_btree_key     *key,
 684         union xfs_btree_rec     *rec)
 685 {
 686         ASSERT(key->bmbt.br_startoff != 0);
 687
 688         xfs_bmbt_disk_set_allf(&rec->bmbt, be64_to_cpu(key->bmbt.br_startoff),
 689                                0, 0, XFS_EXT_NORM);
 690 }
 691
 692 STATIC void
 693 xfs_bmbt_init_rec_from_cur(
 694         struct xfs_btree_cur    *cur,
 695         union xfs_btree_rec     *rec)
 696 {
 697         xfs_bmbt_disk_set_all(&rec->bmbt, &cur->bc_rec.b);
 698 }
 699
 700 STATIC void
 701 xfs_bmbt_init_ptr_from_cur(
 702         struct xfs_btree_cur    *cur,
 703         union xfs_btree_ptr     *ptr)
 704 {
 705         ptr->l = 0;
 706 }
 707
 708 STATIC __int64_t
 709 xfs_bmbt_key_diff(
 710         struct xfs_btree_cur    *cur,
 711         union xfs_btree_key     *key)
 712 {
 713         return (__int64_t)be64_to_cpu(key->bmbt.br_startoff) -
 714                                       cur->bc_rec.b.br_startoff;
 715 }
 716
 717 #ifdef DEBUG
 718 STATIC int
 719 xfs_bmbt_keys_inorder(
 720         struct xfs_btree_cur    *cur,
 721         union xfs_btree_key     *k1,
 722         union xfs_btree_key     *k2)
 723 {
 724         return be64_to_cpu(k1->bmbt.br_startoff) <
 725                 be64_to_cpu(k2->bmbt.br_startoff);
 726 }
 727
 728 STATIC int
 729 xfs_bmbt_recs_inorder(
 730         struct xfs_btree_cur    *cur,
 731         union xfs_btree_rec     *r1,
 732         union xfs_btree_rec     *r2)
 733 {
 734         return xfs_bmbt_disk_get_startoff(&r1->bmbt) +
 735                 xfs_bmbt_disk_get_blockcount(&r1->bmbt) <=
 736                 xfs_bmbt_disk_get_startoff(&r2->bmbt);
 737 }
 738 #endif  /* DEBUG */
 739
 740 #ifdef XFS_BTREE_TRACE
 741 ktrace_t        *xfs_bmbt_trace_buf;
 742
 743 STATIC void
 744 xfs_bmbt_trace_enter(
 745         struct xfs_btree_cur    *cur,
 746         const char              *func,
 747         char                    *s,
 748         int                     type,
 749         int                     line,
 750         __psunsigned_t          a0,
 751         __psunsigned_t          a1,
 752         __psunsigned_t          a2,
 753         __psunsigned_t          a3,
 754         __psunsigned_t          a4,
 755         __psunsigned_t          a5,
 756         __psunsigned_t          a6,
 757         __psunsigned_t          a7,
 758         __psunsigned_t          a8,
 759         __psunsigned_t          a9,
 760         __psunsigned_t          a10)
 761 {
 762         struct xfs_inode        *ip = cur->bc_private.b.ip;
 763         int                     whichfork = cur->bc_private.b.whichfork;
 764
 765         ktrace_enter(xfs_bmbt_trace_buf,
 766                 (void *)((__psint_t)type | (whichfork << 8) | (line << 16)),
 767                 (void *)func, (void *)s, (void *)ip, (void *)cur,
 768                 (void *)a0, (void *)a1, (void *)a2, (void *)a3,
 769                 (void *)a4, (void *)a5, (void *)a6, (void *)a7,
 770                 (void *)a8, (void *)a9, (void *)a10);
 771 }
 772
 773 STATIC void
 774 xfs_bmbt_trace_cursor(
 775         struct xfs_btree_cur    *cur,
 776         __uint32_t              *s0,
 777         __uint64_t              *l0,
 778         __uint64_t              *l1)
 779 {
 780         struct xfs_bmbt_rec_host r;
 781
 782         xfs_bmbt_set_all(&r, &cur->bc_rec.b);
 783
 784         *s0 = (cur->bc_nlevels << 24) |
 785               (cur->bc_private.b.flags << 16) |
 786                cur->bc_private.b.allocated;
 787         *l0 = r.l0;
 788         *l1 = r.l1;
 789 }
 790
 791 STATIC void
 792 xfs_bmbt_trace_key(
 793         struct xfs_btree_cur    *cur,
 794         union xfs_btree_key     *key,
 795         __uint64_t              *l0,
 796         __uint64_t              *l1)
 797 {
 798         *l0 = be64_to_cpu(key->bmbt.br_startoff);
 799         *l1 = 0;
 800 }
 801
 802 /* Endian flipping versions of the bmbt extraction functions */
 803 STATIC void
 804 xfs_bmbt_disk_get_all(
 805         xfs_bmbt_rec_t  *r,
 806         xfs_bmbt_irec_t *s)
 807 {
 808         __xfs_bmbt_get_all(get_unaligned_be64(&r->l0),
 809                                 get_unaligned_be64(&r->l1), s);
 810 }
 811
 812 STATIC void
 813 xfs_bmbt_trace_record(
 814         struct xfs_btree_cur    *cur,
 815         union xfs_btree_rec     *rec,
 816         __uint64_t              *l0,
 817         __uint64_t              *l1,
 818         __uint64_t              *l2)
 819 {
 820         struct xfs_bmbt_irec    irec;
 821
 822         xfs_bmbt_disk_get_all(&rec->bmbt, &irec);
 823         *l0 = irec.br_startoff;
 824         *l1 = irec.br_startblock;
 825         *l2 = irec.br_blockcount;
 826 }
 827 #endif /* XFS_BTREE_TRACE */
 828
 829 static const struct xfs_btree_ops xfs_bmbt_ops = {
 830         .rec_len                = sizeof(xfs_bmbt_rec_t),
 831         .key_len                = sizeof(xfs_bmbt_key_t),
 832
 833         .dup_cursor             = xfs_bmbt_dup_cursor,
 834         .update_cursor          = xfs_bmbt_update_cursor,
 835         .alloc_block            = xfs_bmbt_alloc_block,
 836         .free_block             = xfs_bmbt_free_block,
 837         .get_maxrecs            = xfs_bmbt_get_maxrecs,
 838         .get_minrecs            = xfs_bmbt_get_minrecs,
 839         .get_dmaxrecs           = xfs_bmbt_get_dmaxrecs,
 840         .init_key_from_rec      = xfs_bmbt_init_key_from_rec,
 841         .init_rec_from_key      = xfs_bmbt_init_rec_from_key,
 842         .init_rec_from_cur      = xfs_bmbt_init_rec_from_cur,
 843         .init_ptr_from_cur      = xfs_bmbt_init_ptr_from_cur,
 844         .key_diff               = xfs_bmbt_key_diff,
 845
 846 #ifdef DEBUG
 847         .keys_inorder           = xfs_bmbt_keys_inorder,
 848         .recs_inorder           = xfs_bmbt_recs_inorder,
 849 #endif
 850
 851 #ifdef XFS_BTREE_TRACE
 852         .trace_enter            = xfs_bmbt_trace_enter,
 853         .trace_cursor           = xfs_bmbt_trace_cursor,
 854         .trace_key              = xfs_bmbt_trace_key,
 855         .trace_record           = xfs_bmbt_trace_record,
 856 #endif
 857 };
 858
 859 /*
 860  * Allocate a new bmap btree cursor.
 861  */
 862 struct xfs_btree_cur *                          /* new bmap btree cursor */
 863 xfs_bmbt_init_cursor(
 864         struct xfs_mount        *mp,            /* file system mount point */
 865         struct xfs_trans        *tp,            /* transaction pointer */
 866         struct xfs_inode        *ip,            /* inode owning the btree */
 867         int                     whichfork)      /* data or attr fork */
 868 {
 869         struct xfs_ifork        *ifp = XFS_IFORK_PTR(ip, whichfork);
 870         struct xfs_btree_cur    *cur;
 871
 872         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 873
 874         cur->bc_tp = tp;
 875         cur->bc_mp = mp;
 876         cur->bc_nlevels = be16_to_cpu(ifp->if_broot->bb_level) + 1;
 877         cur->bc_btnum = XFS_BTNUM_BMAP;
 878         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 879
 880         cur->bc_ops = &xfs_bmbt_ops;
 881         cur->bc_flags = XFS_BTREE_LONG_PTRS | XFS_BTREE_ROOT_IN_INODE;
 882
 883         cur->bc_private.b.forksize = XFS_IFORK_SIZE(ip, whichfork);
 884         cur->bc_private.b.ip = ip;
 885         cur->bc_private.b.firstblock = NULLFSBLOCK;
 886         cur->bc_private.b.flist = NULL;
 887         cur->bc_private.b.allocated = 0;
 888         cur->bc_private.b.flags = 0;
 889         cur->bc_private.b.whichfork = whichfork;
 890
 891         return cur;
 892 }
 893
 894 /*
 895  * Calculate number of records in a bmap btree block.
 896  */
 897 int
 898 xfs_bmbt_maxrecs(
 899         struct xfs_mount        *mp,
 900         int                     blocklen,
 901         int                     leaf)
 902 {
 903         blocklen -= XFS_BMBT_BLOCK_LEN(mp);
 904
 905         if (leaf)
 906                 return blocklen / sizeof(xfs_bmbt_rec_t);
 907         return blocklen / (sizeof(xfs_bmbt_key_t) + sizeof(xfs_bmbt_ptr_t));
 908 }
 909
 910 /*
 911  * Calculate number of records in a bmap btree inode root.
 912  */
 913 int
 914 xfs_bmdr_maxrecs(
 915         struct xfs_mount        *mp,
 916         int                     blocklen,
 917         int                     leaf)
 918 {
 919         blocklen -= sizeof(xfs_bmdr_block_t);
 920
 921         if (leaf)
 922                 return blocklen / sizeof(xfs_bmdr_rec_t);
 923         return blocklen / (sizeof(xfs_bmdr_key_t) + sizeof(xfs_bmdr_ptr_t));
 924 }