fs/xfs/xfs_attr_inactive.c

   1 /*
   2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   3  * Copyright (c) 2013 Red Hat, Inc.
   4  * All Rights Reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it would be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write the Free Software Foundation,
  17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18  */
  19 #include "xfs.h"
  20 #include "xfs_fs.h"
  21 #include "xfs_shared.h"
  22 #include "xfs_format.h"
  23 #include "xfs_log_format.h"
  24 #include "xfs_trans_resv.h"
  25 #include "xfs_bit.h"
  26 #include "xfs_sb.h"
  27 #include "xfs_ag.h"
  28 #include "xfs_mount.h"
  29 #include "xfs_da_format.h"
  30 #include "xfs_da_btree.h"
  31 #include "xfs_inode.h"
  32 #include "xfs_alloc.h"
  33 #include "xfs_attr_remote.h"
  34 #include "xfs_trans.h"
  35 #include "xfs_inode_item.h"
  36 #include "xfs_bmap.h"
  37 #include "xfs_attr.h"
  38 #include "xfs_attr_leaf.h"
  39 #include "xfs_error.h"
  40 #include "xfs_quota.h"
  41 #include "xfs_trace.h"
  42 #include "xfs_dinode.h"
  43 #include "xfs_dir2.h"
  44
  45 /*
  46  * Look at all the extents for this logical region,
  47  * invalidate any buffers that are incore/in transactions.
  48  */
  49 STATIC int
  50 xfs_attr3_leaf_freextent(
  51         struct xfs_trans        **trans,
  52         struct xfs_inode        *dp,
  53         xfs_dablk_t             blkno,
  54         int                     blkcnt)
  55 {
  56         struct xfs_bmbt_irec    map;
  57         struct xfs_buf          *bp;
  58         xfs_dablk_t             tblkno;
  59         xfs_daddr_t             dblkno;
  60         int                     tblkcnt;
  61         int                     dblkcnt;
  62         int                     nmap;
  63         int                     error;
  64
  65         /*
  66          * Roll through the "value", invalidating the attribute value's
  67          * blocks.
  68          */
  69         tblkno = blkno;
  70         tblkcnt = blkcnt;
  71         while (tblkcnt > 0) {
  72                 /*
  73                  * Try to remember where we decided to put the value.
  74                  */
  75                 nmap = 1;
  76                 error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
  77                                        &map, &nmap, XFS_BMAPI_ATTRFORK);
  78                 if (error) {
  79                         return(error);
  80                 }
  81                 ASSERT(nmap == 1);
  82                 ASSERT(map.br_startblock != DELAYSTARTBLOCK);
  83
  84                 /*
  85                  * If it's a hole, these are already unmapped
  86                  * so there's nothing to invalidate.
  87                  */
  88                 if (map.br_startblock != HOLESTARTBLOCK) {
  89
  90                         dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
  91                                                   map.br_startblock);
  92                         dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
  93                                                 map.br_blockcount);
  94                         bp = xfs_trans_get_buf(*trans,
  95                                         dp->i_mount->m_ddev_targp,
  96                                         dblkno, dblkcnt, 0);
  97                         if (!bp)
  98                                 return ENOMEM;
  99                         xfs_trans_binval(*trans, bp);
 100                         /*
 101                          * Roll to next transaction.
 102                          */
 103                         error = xfs_trans_roll(trans, dp);
 104                         if (error)
 105                                 return (error);
 106                 }
 107
 108                 tblkno += map.br_blockcount;
 109                 tblkcnt -= map.br_blockcount;
 110         }
 111
 112         return(0);
 113 }
 114
 115 /*
 116  * Invalidate all of the "remote" value regions pointed to by a particular
 117  * leaf block.
 118  * Note that we must release the lock on the buffer so that we are not
 119  * caught holding something that the logging code wants to flush to disk.
 120  */
 121 STATIC int
 122 xfs_attr3_leaf_inactive(
 123         struct xfs_trans        **trans,
 124         struct xfs_inode        *dp,
 125         struct xfs_buf          *bp)
 126 {
 127         struct xfs_attr_leafblock *leaf;
 128         struct xfs_attr3_icleaf_hdr ichdr;
 129         struct xfs_attr_leaf_entry *entry;
 130         struct xfs_attr_leaf_name_remote *name_rmt;
 131         struct xfs_attr_inactive_list *list;
 132         struct xfs_attr_inactive_list *lp;
 133         int                     error;
 134         int                     count;
 135         int                     size;
 136         int                     tmp;
 137         int                     i;
 138
 139         leaf = bp->b_addr;
 140         xfs_attr3_leaf_hdr_from_disk(&ichdr, leaf);
 141
 142         /*
 143          * Count the number of "remote" value extents.
 144          */
 145         count = 0;
 146         entry = xfs_attr3_leaf_entryp(leaf);
 147         for (i = 0; i < ichdr.count; entry++, i++) {
 148                 if (be16_to_cpu(entry->nameidx) &&
 149                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 150                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 151                         if (name_rmt->valueblk)
 152                                 count++;
 153                 }
 154         }
 155
 156         /*
 157          * If there are no "remote" values, we're done.
 158          */
 159         if (count == 0) {
 160                 xfs_trans_brelse(*trans, bp);
 161                 return 0;
 162         }
 163
 164         /*
 165          * Allocate storage for a list of all the "remote" value extents.
 166          */
 167         size = count * sizeof(xfs_attr_inactive_list_t);
 168         list = kmem_alloc(size, KM_SLEEP);
 169
 170         /*
 171          * Identify each of the "remote" value extents.
 172          */
 173         lp = list;
 174         entry = xfs_attr3_leaf_entryp(leaf);
 175         for (i = 0; i < ichdr.count; entry++, i++) {
 176                 if (be16_to_cpu(entry->nameidx) &&
 177                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 178                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 179                         if (name_rmt->valueblk) {
 180                                 lp->valueblk = be32_to_cpu(name_rmt->valueblk);
 181                                 lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
 182                                                     be32_to_cpu(name_rmt->valuelen));
 183                                 lp++;
 184                         }
 185                 }
 186         }
 187         xfs_trans_brelse(*trans, bp);   /* unlock for trans. in freextent() */
 188
 189         /*
 190          * Invalidate each of the "remote" value extents.
 191          */
 192         error = 0;
 193         for (lp = list, i = 0; i < count; i++, lp++) {
 194                 tmp = xfs_attr3_leaf_freextent(trans, dp,
 195                                 lp->valueblk, lp->valuelen);
 196
 197                 if (error == 0)
 198                         error = tmp;    /* save only the 1st errno */
 199         }
 200
 201         kmem_free(list);
 202         return error;
 203 }
 204
 205 /*
 206  * Recurse (gasp!) through the attribute nodes until we find leaves.
 207  * We're doing a depth-first traversal in order to invalidate everything.
 208  */
 209 STATIC int
 210 xfs_attr3_node_inactive(
 211         struct xfs_trans **trans,
 212         struct xfs_inode *dp,
 213         struct xfs_buf  *bp,
 214         int             level)
 215 {
 216         xfs_da_blkinfo_t *info;
 217         xfs_da_intnode_t *node;
 218         xfs_dablk_t child_fsb;
 219         xfs_daddr_t parent_blkno, child_blkno;
 220         int error, i;
 221         struct xfs_buf *child_bp;
 222         struct xfs_da_node_entry *btree;
 223         struct xfs_da3_icnode_hdr ichdr;
 224
 225         /*
 226          * Since this code is recursive (gasp!) we must protect ourselves.
 227          */
 228         if (level > XFS_DA_NODE_MAXDEPTH) {
 229                 xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 230                 return XFS_ERROR(EIO);
 231         }
 232
 233         node = bp->b_addr;
 234         dp->d_ops->node_hdr_from_disk(&ichdr, node);
 235         parent_blkno = bp->b_bn;
 236         if (!ichdr.count) {
 237                 xfs_trans_brelse(*trans, bp);
 238                 return 0;
 239         }
 240         btree = dp->d_ops->node_tree_p(node);
 241         child_fsb = be32_to_cpu(btree[0].before);
 242         xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 243
 244         /*
 245          * If this is the node level just above the leaves, simply loop
 246          * over the leaves removing all of them.  If this is higher up
 247          * in the tree, recurse downward.
 248          */
 249         for (i = 0; i < ichdr.count; i++) {
 250                 /*
 251                  * Read the subsidiary block to see what we have to work with.
 252                  * Don't do this in a transaction.  This is a depth-first
 253                  * traversal of the tree so we may deal with many blocks
 254                  * before we come back to this one.
 255                  */
 256                 error = xfs_da3_node_read(*trans, dp, child_fsb, -2, &child_bp,
 257                                                 XFS_ATTR_FORK);
 258                 if (error)
 259                         return(error);
 260                 if (child_bp) {
 261                                                 /* save for re-read later */
 262                         child_blkno = XFS_BUF_ADDR(child_bp);
 263
 264                         /*
 265                          * Invalidate the subtree, however we have to.
 266                          */
 267                         info = child_bp->b_addr;
 268                         switch (info->magic) {
 269                         case cpu_to_be16(XFS_DA_NODE_MAGIC):
 270                         case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 271                                 error = xfs_attr3_node_inactive(trans, dp,
 272                                                         child_bp, level + 1);
 273                                 break;
 274                         case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 275                         case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 276                                 error = xfs_attr3_leaf_inactive(trans, dp,
 277                                                         child_bp);
 278                                 break;
 279                         default:
 280                                 error = XFS_ERROR(EIO);
 281                                 xfs_trans_brelse(*trans, child_bp);
 282                                 break;
 283                         }
 284                         if (error)
 285                                 return error;
 286
 287                         /*
 288                          * Remove the subsidiary block from the cache
 289                          * and from the log.
 290                          */
 291                         error = xfs_da_get_buf(*trans, dp, 0, child_blkno,
 292                                 &child_bp, XFS_ATTR_FORK);
 293                         if (error)
 294                                 return error;
 295                         xfs_trans_binval(*trans, child_bp);
 296                 }
 297
 298                 /*
 299                  * If we're not done, re-read the parent to get the next
 300                  * child block number.
 301                  */
 302                 if (i + 1 < ichdr.count) {
 303                         error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
 304                                                  &bp, XFS_ATTR_FORK);
 305                         if (error)
 306                                 return error;
 307                         child_fsb = be32_to_cpu(btree[i + 1].before);
 308                         xfs_trans_brelse(*trans, bp);
 309                 }
 310                 /*
 311                  * Atomically commit the whole invalidate stuff.
 312                  */
 313                 error = xfs_trans_roll(trans, dp);
 314                 if (error)
 315                         return  error;
 316         }
 317
 318         return 0;
 319 }
 320
 321 /*
 322  * Indiscriminately delete the entire attribute fork
 323  *
 324  * Recurse (gasp!) through the attribute nodes until we find leaves.
 325  * We're doing a depth-first traversal in order to invalidate everything.
 326  */
 327 int
 328 xfs_attr3_root_inactive(
 329         struct xfs_trans        **trans,
 330         struct xfs_inode        *dp)
 331 {
 332         struct xfs_da_blkinfo   *info;
 333         struct xfs_buf          *bp;
 334         xfs_daddr_t             blkno;
 335         int                     error;
 336
 337         /*
 338          * Read block 0 to see what we have to work with.
 339          * We only get here if we have extents, since we remove
 340          * the extents in reverse order the extent containing
 341          * block 0 must still be there.
 342          */
 343         error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
 344         if (error)
 345                 return error;
 346         blkno = bp->b_bn;
 347
 348         /*
 349          * Invalidate the tree, even if the "tree" is only a single leaf block.
 350          * This is a depth-first traversal!
 351          */
 352         info = bp->b_addr;
 353         switch (info->magic) {
 354         case cpu_to_be16(XFS_DA_NODE_MAGIC):
 355         case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 356                 error = xfs_attr3_node_inactive(trans, dp, bp, 1);
 357                 break;
 358         case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 359         case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 360                 error = xfs_attr3_leaf_inactive(trans, dp, bp);
 361                 break;
 362         default:
 363                 error = XFS_ERROR(EIO);
 364                 xfs_trans_brelse(*trans, bp);
 365                 break;
 366         }
 367         if (error)
 368                 return error;
 369
 370         /*
 371          * Invalidate the incore copy of the root block.
 372          */
 373         error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
 374         if (error)
 375                 return error;
 376         xfs_trans_binval(*trans, bp);   /* remove from cache */
 377         /*
 378          * Commit the invalidate and start the next transaction.
 379          */
 380         error = xfs_trans_roll(trans, dp);
 381
 382         return error;
 383 }
 384
 385 /*
 386  * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
 387  * removes both the on-disk and in-memory inode fork. Note that this also has to
 388  * handle the condition of inodes without attributes but with an attribute fork
 389  * configured, so we can't use xfs_inode_hasattr() here.
 390  *
 391  * The in-memory attribute fork is removed even on error.
 392  */
 393 int
 394 xfs_attr_inactive(
 395         struct xfs_inode        *dp)
 396 {
 397         struct xfs_trans        *trans;
 398         struct xfs_mount        *mp;
 399         int                     cancel_flags = 0;
 400         int                     lock_mode = XFS_ILOCK_SHARED;
 401         int                     error = 0;
 402
 403         mp = dp->i_mount;
 404         ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
 405
 406         xfs_ilock(dp, lock_mode);
 407         if (!XFS_IFORK_Q(dp))
 408                 goto out_destroy_fork;
 409         xfs_iunlock(dp, lock_mode);
 410
 411         /*
 412          * Start our first transaction of the day.
 413          *
 414          * All future transactions during this code must be "chained" off
 415          * this one via the trans_dup() call.  All transactions will contain
 416          * the inode, and the inode will always be marked with trans_ihold().
 417          * Since the inode will be locked in all transactions, we must log
 418          * the inode in every transaction to let it float upward through
 419          * the log.
 420          */
 421         lock_mode = 0;
 422         trans = xfs_trans_alloc(mp, XFS_TRANS_ATTRINVAL);
 423         error = xfs_trans_reserve(trans, &M_RES(mp)->tr_attrinval, 0, 0);
 424         if (error)
 425                 goto out_cancel;
 426
 427         lock_mode = XFS_ILOCK_EXCL;
 428         cancel_flags = XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT;
 429         xfs_ilock(dp, lock_mode);
 430
 431         if (!XFS_IFORK_Q(dp))
 432                 goto out_cancel;
 433
 434         /*
 435          * No need to make quota reservations here. We expect to release some
 436          * blocks, not allocate, in the common case.
 437          */
 438         xfs_trans_ijoin(trans, dp, 0);
 439
 440         /*
 441          * Invalidate and truncate the attribute fork extents. Make sure the
 442          * fork actually has attributes as otherwise the invalidation has no
 443          * blocks to read and returns an error. In this case, just do the fork
 444          * removal below.
 445          */
 446         if (xfs_inode_hasattr(dp) &&
 447             dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
 448                 error = xfs_attr3_root_inactive(&trans, dp);
 449                 if (error)
 450                         goto out_cancel;
 451
 452                 error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
 453                 if (error)
 454                         goto out_cancel;
 455         }
 456
 457         /* Reset the attribute fork - this also destroys the in-core fork */
 458         xfs_attr_fork_remove(dp, trans);
 459
 460         error = xfs_trans_commit(trans, XFS_TRANS_RELEASE_LOG_RES);
 461         xfs_iunlock(dp, lock_mode);
 462         return(error);
 463
 464 out_cancel:
 465         xfs_trans_cancel(trans, cancel_flags);
 466 out_destroy_fork:
 467         /* kill the in-core attr fork before we drop the inode lock */
 468         if (dp->i_afp)
 469                 xfs_idestroy_fork(dp, XFS_ATTR_FORK);
 470         if (lock_mode)
 471                 xfs_iunlock(dp, lock_mode);
 472         return(error);
 473 }