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_mount.h"
  27 #include "xfs_da_format.h"
  28 #include "xfs_da_btree.h"
  29 #include "xfs_inode.h"
  30 #include "xfs_alloc.h"
  31 #include "xfs_attr_remote.h"
  32 #include "xfs_trans.h"
  33 #include "xfs_inode_item.h"
  34 #include "xfs_bmap.h"
  35 #include "xfs_attr.h"
  36 #include "xfs_attr_leaf.h"
  37 #include "xfs_error.h"
  38 #include "xfs_quota.h"
  39 #include "xfs_trace.h"
  40 #include "xfs_dir2.h"
  41
  42 /*
  43  * Look at all the extents for this logical region,
  44  * invalidate any buffers that are incore/in transactions.
  45  */
  46 STATIC int
  47 xfs_attr3_leaf_freextent(
  48         struct xfs_trans        **trans,
  49         struct xfs_inode        *dp,
  50         xfs_dablk_t             blkno,
  51         int                     blkcnt)
  52 {
  53         struct xfs_bmbt_irec    map;
  54         struct xfs_buf          *bp;
  55         xfs_dablk_t             tblkno;
  56         xfs_daddr_t             dblkno;
  57         int                     tblkcnt;
  58         int                     dblkcnt;
  59         int                     nmap;
  60         int                     error;
  61
  62         /*
  63          * Roll through the "value", invalidating the attribute value's
  64          * blocks.
  65          */
  66         tblkno = blkno;
  67         tblkcnt = blkcnt;
  68         while (tblkcnt > 0) {
  69                 /*
  70                  * Try to remember where we decided to put the value.
  71                  */
  72                 nmap = 1;
  73                 error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
  74                                        &map, &nmap, XFS_BMAPI_ATTRFORK);
  75                 if (error) {
  76                         return error;
  77                 }
  78                 ASSERT(nmap == 1);
  79                 ASSERT(map.br_startblock != DELAYSTARTBLOCK);
  80
  81                 /*
  82                  * If it's a hole, these are already unmapped
  83                  * so there's nothing to invalidate.
  84                  */
  85                 if (map.br_startblock != HOLESTARTBLOCK) {
  86
  87                         dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
  88                                                   map.br_startblock);
  89                         dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
  90                                                 map.br_blockcount);
  91                         bp = xfs_trans_get_buf(*trans,
  92                                         dp->i_mount->m_ddev_targp,
  93                                         dblkno, dblkcnt, 0);
  94                         if (!bp)
  95                                 return -ENOMEM;
  96                         xfs_trans_binval(*trans, bp);
  97                         /*
  98                          * Roll to next transaction.
  99                          */
 100                         error = xfs_trans_roll(trans, dp);
 101                         if (error)
 102                                 return error;
 103                 }
 104
 105                 tblkno += map.br_blockcount;
 106                 tblkcnt -= map.br_blockcount;
 107         }
 108
 109         return 0;
 110 }
 111
 112 /*
 113  * Invalidate all of the "remote" value regions pointed to by a particular
 114  * leaf block.
 115  * Note that we must release the lock on the buffer so that we are not
 116  * caught holding something that the logging code wants to flush to disk.
 117  */
 118 STATIC int
 119 xfs_attr3_leaf_inactive(
 120         struct xfs_trans        **trans,
 121         struct xfs_inode        *dp,
 122         struct xfs_buf          *bp)
 123 {
 124         struct xfs_attr_leafblock *leaf;
 125         struct xfs_attr3_icleaf_hdr ichdr;
 126         struct xfs_attr_leaf_entry *entry;
 127         struct xfs_attr_leaf_name_remote *name_rmt;
 128         struct xfs_attr_inactive_list *list;
 129         struct xfs_attr_inactive_list *lp;
 130         int                     error;
 131         int                     count;
 132         int                     size;
 133         int                     tmp;
 134         int                     i;
 135         struct xfs_mount        *mp = bp->b_target->bt_mount;
 136
 137         leaf = bp->b_addr;
 138         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
 139
 140         /*
 141          * Count the number of "remote" value extents.
 142          */
 143         count = 0;
 144         entry = xfs_attr3_leaf_entryp(leaf);
 145         for (i = 0; i < ichdr.count; entry++, i++) {
 146                 if (be16_to_cpu(entry->nameidx) &&
 147                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 148                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 149                         if (name_rmt->valueblk)
 150                                 count++;
 151                 }
 152         }
 153
 154         /*
 155          * If there are no "remote" values, we're done.
 156          */
 157         if (count == 0) {
 158                 xfs_trans_brelse(*trans, bp);
 159                 return 0;
 160         }
 161
 162         /*
 163          * Allocate storage for a list of all the "remote" value extents.
 164          */
 165         size = count * sizeof(xfs_attr_inactive_list_t);
 166         list = kmem_alloc(size, KM_SLEEP);
 167
 168         /*
 169          * Identify each of the "remote" value extents.
 170          */
 171         lp = list;
 172         entry = xfs_attr3_leaf_entryp(leaf);
 173         for (i = 0; i < ichdr.count; entry++, i++) {
 174                 if (be16_to_cpu(entry->nameidx) &&
 175                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 176                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 177                         if (name_rmt->valueblk) {
 178                                 lp->valueblk = be32_to_cpu(name_rmt->valueblk);
 179                                 lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
 180                                                     be32_to_cpu(name_rmt->valuelen));
 181                                 lp++;
 182                         }
 183                 }
 184         }
 185         xfs_trans_brelse(*trans, bp);   /* unlock for trans. in freextent() */
 186
 187         /*
 188          * Invalidate each of the "remote" value extents.
 189          */
 190         error = 0;
 191         for (lp = list, i = 0; i < count; i++, lp++) {
 192                 tmp = xfs_attr3_leaf_freextent(trans, dp,
 193                                 lp->valueblk, lp->valuelen);
 194
 195                 if (error == 0)
 196                         error = tmp;    /* save only the 1st errno */
 197         }
 198
 199         kmem_free(list);
 200         return error;
 201 }
 202
 203 /*
 204  * Recurse (gasp!) through the attribute nodes until we find leaves.
 205  * We're doing a depth-first traversal in order to invalidate everything.
 206  */
 207 STATIC int
 208 xfs_attr3_node_inactive(
 209         struct xfs_trans **trans,
 210         struct xfs_inode *dp,
 211         struct xfs_buf  *bp,
 212         int             level)
 213 {
 214         xfs_da_blkinfo_t *info;
 215         xfs_da_intnode_t *node;
 216         xfs_dablk_t child_fsb;
 217         xfs_daddr_t parent_blkno, child_blkno;
 218         int error, i;
 219         struct xfs_buf *child_bp;
 220         struct xfs_da_node_entry *btree;
 221         struct xfs_da3_icnode_hdr ichdr;
 222
 223         /*
 224          * Since this code is recursive (gasp!) we must protect ourselves.
 225          */
 226         if (level > XFS_DA_NODE_MAXDEPTH) {
 227                 xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 228                 return -EIO;
 229         }
 230
 231         node = bp->b_addr;
 232         dp->d_ops->node_hdr_from_disk(&ichdr, node);
 233         parent_blkno = bp->b_bn;
 234         if (!ichdr.count) {
 235                 xfs_trans_brelse(*trans, bp);
 236                 return 0;
 237         }
 238         btree = dp->d_ops->node_tree_p(node);
 239         child_fsb = be32_to_cpu(btree[0].before);
 240         xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 241
 242         /*
 243          * If this is the node level just above the leaves, simply loop
 244          * over the leaves removing all of them.  If this is higher up
 245          * in the tree, recurse downward.
 246          */
 247         for (i = 0; i < ichdr.count; i++) {
 248                 /*
 249                  * Read the subsidiary block to see what we have to work with.
 250                  * Don't do this in a transaction.  This is a depth-first
 251                  * traversal of the tree so we may deal with many blocks
 252                  * before we come back to this one.
 253                  */
 254                 error = xfs_da3_node_read(*trans, dp, child_fsb, -2, &child_bp,
 255                                                 XFS_ATTR_FORK);
 256                 if (error)
 257                         return error;
 258                 if (child_bp) {
 259                                                 /* save for re-read later */
 260                         child_blkno = XFS_BUF_ADDR(child_bp);
 261
 262                         /*
 263                          * Invalidate the subtree, however we have to.
 264                          */
 265                         info = child_bp->b_addr;
 266                         switch (info->magic) {
 267                         case cpu_to_be16(XFS_DA_NODE_MAGIC):
 268                         case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 269                                 error = xfs_attr3_node_inactive(trans, dp,
 270                                                         child_bp, level + 1);
 271                                 break;
 272                         case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 273                         case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 274                                 error = xfs_attr3_leaf_inactive(trans, dp,
 275                                                         child_bp);
 276                                 break;
 277                         default:
 278                                 error = -EIO;
 279                                 xfs_trans_brelse(*trans, child_bp);
 280                                 break;
 281                         }
 282                         if (error)
 283                                 return error;
 284
 285                         /*
 286                          * Remove the subsidiary block from the cache
 287                          * and from the log.
 288                          */
 289                         error = xfs_da_get_buf(*trans, dp, 0, child_blkno,
 290                                 &child_bp, XFS_ATTR_FORK);
 291                         if (error)
 292                                 return error;
 293                         xfs_trans_binval(*trans, child_bp);
 294                 }
 295
 296                 /*
 297                  * If we're not done, re-read the parent to get the next
 298                  * child block number.
 299                  */
 300                 if (i + 1 < ichdr.count) {
 301                         error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
 302                                                  &bp, XFS_ATTR_FORK);
 303                         if (error)
 304                                 return error;
 305                         node = bp->b_addr;
 306                         btree = dp->d_ops->node_tree_p(node);
 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 static 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 = -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                     lock_mode = XFS_ILOCK_SHARED;
 400         int                     error = 0;
 401
 402         mp = dp->i_mount;
 403         ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
 404
 405         xfs_ilock(dp, lock_mode);
 406         if (!XFS_IFORK_Q(dp))
 407                 goto out_destroy_fork;
 408         xfs_iunlock(dp, lock_mode);
 409
 410         lock_mode = 0;
 411
 412         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
 413         if (error)
 414                 goto out_destroy_fork;
 415
 416         lock_mode = XFS_ILOCK_EXCL;
 417         xfs_ilock(dp, lock_mode);
 418
 419         if (!XFS_IFORK_Q(dp))
 420                 goto out_cancel;
 421
 422         /*
 423          * No need to make quota reservations here. We expect to release some
 424          * blocks, not allocate, in the common case.
 425          */
 426         xfs_trans_ijoin(trans, dp, 0);
 427
 428         /*
 429          * Invalidate and truncate the attribute fork extents. Make sure the
 430          * fork actually has attributes as otherwise the invalidation has no
 431          * blocks to read and returns an error. In this case, just do the fork
 432          * removal below.
 433          */
 434         if (xfs_inode_hasattr(dp) &&
 435             dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
 436                 error = xfs_attr3_root_inactive(&trans, dp);
 437                 if (error)
 438                         goto out_cancel;
 439
 440                 error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
 441                 if (error)
 442                         goto out_cancel;
 443         }
 444
 445         /* Reset the attribute fork - this also destroys the in-core fork */
 446         xfs_attr_fork_remove(dp, trans);
 447
 448         error = xfs_trans_commit(trans);
 449         xfs_iunlock(dp, lock_mode);
 450         return error;
 451
 452 out_cancel:
 453         xfs_trans_cancel(trans);
 454 out_destroy_fork:
 455         /* kill the in-core attr fork before we drop the inode lock */
 456         if (dp->i_afp)
 457                 xfs_idestroy_fork(dp, XFS_ATTR_FORK);
 458         if (lock_mode)
 459                 xfs_iunlock(dp, lock_mode);
 460         return error;
 461 }