fs/xfs/xfs_attr_inactive.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
   4  * Copyright (c) 2013 Red Hat, Inc.
   5  * All Rights Reserved.
   6  */
   7 #include "xfs.h"
   8 #include "xfs_fs.h"
   9 #include "xfs_shared.h"
  10 #include "xfs_format.h"
  11 #include "xfs_log_format.h"
  12 #include "xfs_trans_resv.h"
  13 #include "xfs_bit.h"
  14 #include "xfs_mount.h"
  15 #include "xfs_da_format.h"
  16 #include "xfs_da_btree.h"
  17 #include "xfs_inode.h"
  18 #include "xfs_alloc.h"
  19 #include "xfs_attr_remote.h"
  20 #include "xfs_trans.h"
  21 #include "xfs_inode_item.h"
  22 #include "xfs_bmap.h"
  23 #include "xfs_attr.h"
  24 #include "xfs_attr_leaf.h"
  25 #include "xfs_error.h"
  26 #include "xfs_quota.h"
  27 #include "xfs_trace.h"
  28 #include "xfs_dir2.h"
  29 #include "xfs_defer.h"
  30
  31 /*
  32  * Look at all the extents for this logical region,
  33  * invalidate any buffers that are incore/in transactions.
  34  */
  35 STATIC int
  36 xfs_attr3_leaf_freextent(
  37         struct xfs_trans        **trans,
  38         struct xfs_inode        *dp,
  39         xfs_dablk_t             blkno,
  40         int                     blkcnt)
  41 {
  42         struct xfs_bmbt_irec    map;
  43         struct xfs_buf          *bp;
  44         xfs_dablk_t             tblkno;
  45         xfs_daddr_t             dblkno;
  46         int                     tblkcnt;
  47         int                     dblkcnt;
  48         int                     nmap;
  49         int                     error;
  50
  51         /*
  52          * Roll through the "value", invalidating the attribute value's
  53          * blocks.
  54          */
  55         tblkno = blkno;
  56         tblkcnt = blkcnt;
  57         while (tblkcnt > 0) {
  58                 /*
  59                  * Try to remember where we decided to put the value.
  60                  */
  61                 nmap = 1;
  62                 error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
  63                                        &map, &nmap, XFS_BMAPI_ATTRFORK);
  64                 if (error) {
  65                         return error;
  66                 }
  67                 ASSERT(nmap == 1);
  68                 ASSERT(map.br_startblock != DELAYSTARTBLOCK);
  69
  70                 /*
  71                  * If it's a hole, these are already unmapped
  72                  * so there's nothing to invalidate.
  73                  */
  74                 if (map.br_startblock != HOLESTARTBLOCK) {
  75
  76                         dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
  77                                                   map.br_startblock);
  78                         dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
  79                                                 map.br_blockcount);
  80                         bp = xfs_trans_get_buf(*trans,
  81                                         dp->i_mount->m_ddev_targp,
  82                                         dblkno, dblkcnt, 0);
  83                         if (!bp)
  84                                 return -ENOMEM;
  85                         xfs_trans_binval(*trans, bp);
  86                         /*
  87                          * Roll to next transaction.
  88                          */
  89                         error = xfs_trans_roll_inode(trans, dp);
  90                         if (error)
  91                                 return error;
  92                 }
  93
  94                 tblkno += map.br_blockcount;
  95                 tblkcnt -= map.br_blockcount;
  96         }
  97
  98         return 0;
  99 }
 100
 101 /*
 102  * Invalidate all of the "remote" value regions pointed to by a particular
 103  * leaf block.
 104  * Note that we must release the lock on the buffer so that we are not
 105  * caught holding something that the logging code wants to flush to disk.
 106  */
 107 STATIC int
 108 xfs_attr3_leaf_inactive(
 109         struct xfs_trans        **trans,
 110         struct xfs_inode        *dp,
 111         struct xfs_buf          *bp)
 112 {
 113         struct xfs_attr_leafblock *leaf;
 114         struct xfs_attr3_icleaf_hdr ichdr;
 115         struct xfs_attr_leaf_entry *entry;
 116         struct xfs_attr_leaf_name_remote *name_rmt;
 117         struct xfs_attr_inactive_list *list;
 118         struct xfs_attr_inactive_list *lp;
 119         int                     error;
 120         int                     count;
 121         int                     size;
 122         int                     tmp;
 123         int                     i;
 124         struct xfs_mount        *mp = bp->b_target->bt_mount;
 125
 126         leaf = bp->b_addr;
 127         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
 128
 129         /*
 130          * Count the number of "remote" value extents.
 131          */
 132         count = 0;
 133         entry = xfs_attr3_leaf_entryp(leaf);
 134         for (i = 0; i < ichdr.count; entry++, i++) {
 135                 if (be16_to_cpu(entry->nameidx) &&
 136                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 137                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 138                         if (name_rmt->valueblk)
 139                                 count++;
 140                 }
 141         }
 142
 143         /*
 144          * If there are no "remote" values, we're done.
 145          */
 146         if (count == 0) {
 147                 xfs_trans_brelse(*trans, bp);
 148                 return 0;
 149         }
 150
 151         /*
 152          * Allocate storage for a list of all the "remote" value extents.
 153          */
 154         size = count * sizeof(xfs_attr_inactive_list_t);
 155         list = kmem_alloc(size, KM_SLEEP);
 156
 157         /*
 158          * Identify each of the "remote" value extents.
 159          */
 160         lp = list;
 161         entry = xfs_attr3_leaf_entryp(leaf);
 162         for (i = 0; i < ichdr.count; entry++, i++) {
 163                 if (be16_to_cpu(entry->nameidx) &&
 164                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 165                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 166                         if (name_rmt->valueblk) {
 167                                 lp->valueblk = be32_to_cpu(name_rmt->valueblk);
 168                                 lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
 169                                                     be32_to_cpu(name_rmt->valuelen));
 170                                 lp++;
 171                         }
 172                 }
 173         }
 174         xfs_trans_brelse(*trans, bp);   /* unlock for trans. in freextent() */
 175
 176         /*
 177          * Invalidate each of the "remote" value extents.
 178          */
 179         error = 0;
 180         for (lp = list, i = 0; i < count; i++, lp++) {
 181                 tmp = xfs_attr3_leaf_freextent(trans, dp,
 182                                 lp->valueblk, lp->valuelen);
 183
 184                 if (error == 0)
 185                         error = tmp;    /* save only the 1st errno */
 186         }
 187
 188         kmem_free(list);
 189         return error;
 190 }
 191
 192 /*
 193  * Recurse (gasp!) through the attribute nodes until we find leaves.
 194  * We're doing a depth-first traversal in order to invalidate everything.
 195  */
 196 STATIC int
 197 xfs_attr3_node_inactive(
 198         struct xfs_trans **trans,
 199         struct xfs_inode *dp,
 200         struct xfs_buf  *bp,
 201         int             level)
 202 {
 203         xfs_da_blkinfo_t *info;
 204         xfs_da_intnode_t *node;
 205         xfs_dablk_t child_fsb;
 206         xfs_daddr_t parent_blkno, child_blkno;
 207         int error, i;
 208         struct xfs_buf *child_bp;
 209         struct xfs_da_node_entry *btree;
 210         struct xfs_da3_icnode_hdr ichdr;
 211
 212         /*
 213          * Since this code is recursive (gasp!) we must protect ourselves.
 214          */
 215         if (level > XFS_DA_NODE_MAXDEPTH) {
 216                 xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 217                 return -EIO;
 218         }
 219
 220         node = bp->b_addr;
 221         dp->d_ops->node_hdr_from_disk(&ichdr, node);
 222         parent_blkno = bp->b_bn;
 223         if (!ichdr.count) {
 224                 xfs_trans_brelse(*trans, bp);
 225                 return 0;
 226         }
 227         btree = dp->d_ops->node_tree_p(node);
 228         child_fsb = be32_to_cpu(btree[0].before);
 229         xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 230
 231         /*
 232          * If this is the node level just above the leaves, simply loop
 233          * over the leaves removing all of them.  If this is higher up
 234          * in the tree, recurse downward.
 235          */
 236         for (i = 0; i < ichdr.count; i++) {
 237                 /*
 238                  * Read the subsidiary block to see what we have to work with.
 239                  * Don't do this in a transaction.  This is a depth-first
 240                  * traversal of the tree so we may deal with many blocks
 241                  * before we come back to this one.
 242                  */
 243                 error = xfs_da3_node_read(*trans, dp, child_fsb, -1, &child_bp,
 244                                           XFS_ATTR_FORK);
 245                 if (error)
 246                         return error;
 247
 248                 /* save for re-read later */
 249                 child_blkno = XFS_BUF_ADDR(child_bp);
 250
 251                 /*
 252                  * Invalidate the subtree, however we have to.
 253                  */
 254                 info = child_bp->b_addr;
 255                 switch (info->magic) {
 256                 case cpu_to_be16(XFS_DA_NODE_MAGIC):
 257                 case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 258                         error = xfs_attr3_node_inactive(trans, dp, child_bp,
 259                                                         level + 1);
 260                         break;
 261                 case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 262                 case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 263                         error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
 264                         break;
 265                 default:
 266                         error = -EIO;
 267                         xfs_trans_brelse(*trans, child_bp);
 268                         break;
 269                 }
 270                 if (error)
 271                         return error;
 272
 273                 /*
 274                  * Remove the subsidiary block from the cache and from the log.
 275                  */
 276                 error = xfs_da_get_buf(*trans, dp, 0, child_blkno, &child_bp,
 277                                        XFS_ATTR_FORK);
 278                 if (error)
 279                         return error;
 280                 xfs_trans_binval(*trans, child_bp);
 281
 282                 /*
 283                  * If we're not done, re-read the parent to get the next
 284                  * child block number.
 285                  */
 286                 if (i + 1 < ichdr.count) {
 287                         error = xfs_da3_node_read(*trans, dp, 0, parent_blkno,
 288                                                  &bp, XFS_ATTR_FORK);
 289                         if (error)
 290                                 return error;
 291                         node = bp->b_addr;
 292                         btree = dp->d_ops->node_tree_p(node);
 293                         child_fsb = be32_to_cpu(btree[i + 1].before);
 294                         xfs_trans_brelse(*trans, bp);
 295                 }
 296                 /*
 297                  * Atomically commit the whole invalidate stuff.
 298                  */
 299                 error = xfs_trans_roll_inode(trans, dp);
 300                 if (error)
 301                         return  error;
 302         }
 303
 304         return 0;
 305 }
 306
 307 /*
 308  * Indiscriminately delete the entire attribute fork
 309  *
 310  * Recurse (gasp!) through the attribute nodes until we find leaves.
 311  * We're doing a depth-first traversal in order to invalidate everything.
 312  */
 313 static int
 314 xfs_attr3_root_inactive(
 315         struct xfs_trans        **trans,
 316         struct xfs_inode        *dp)
 317 {
 318         struct xfs_da_blkinfo   *info;
 319         struct xfs_buf          *bp;
 320         xfs_daddr_t             blkno;
 321         int                     error;
 322
 323         /*
 324          * Read block 0 to see what we have to work with.
 325          * We only get here if we have extents, since we remove
 326          * the extents in reverse order the extent containing
 327          * block 0 must still be there.
 328          */
 329         error = xfs_da3_node_read(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
 330         if (error)
 331                 return error;
 332         blkno = bp->b_bn;
 333
 334         /*
 335          * Invalidate the tree, even if the "tree" is only a single leaf block.
 336          * This is a depth-first traversal!
 337          */
 338         info = bp->b_addr;
 339         switch (info->magic) {
 340         case cpu_to_be16(XFS_DA_NODE_MAGIC):
 341         case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 342                 error = xfs_attr3_node_inactive(trans, dp, bp, 1);
 343                 break;
 344         case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 345         case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 346                 error = xfs_attr3_leaf_inactive(trans, dp, bp);
 347                 break;
 348         default:
 349                 error = -EIO;
 350                 xfs_trans_brelse(*trans, bp);
 351                 break;
 352         }
 353         if (error)
 354                 return error;
 355
 356         /*
 357          * Invalidate the incore copy of the root block.
 358          */
 359         error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
 360         if (error)
 361                 return error;
 362         xfs_trans_binval(*trans, bp);   /* remove from cache */
 363         /*
 364          * Commit the invalidate and start the next transaction.
 365          */
 366         error = xfs_trans_roll_inode(trans, dp);
 367
 368         return error;
 369 }
 370
 371 /*
 372  * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
 373  * removes both the on-disk and in-memory inode fork. Note that this also has to
 374  * handle the condition of inodes without attributes but with an attribute fork
 375  * configured, so we can't use xfs_inode_hasattr() here.
 376  *
 377  * The in-memory attribute fork is removed even on error.
 378  */
 379 int
 380 xfs_attr_inactive(
 381         struct xfs_inode        *dp)
 382 {
 383         struct xfs_trans        *trans;
 384         struct xfs_mount        *mp;
 385         int                     lock_mode = XFS_ILOCK_SHARED;
 386         int                     error = 0;
 387
 388         mp = dp->i_mount;
 389         ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
 390
 391         xfs_ilock(dp, lock_mode);
 392         if (!XFS_IFORK_Q(dp))
 393                 goto out_destroy_fork;
 394         xfs_iunlock(dp, lock_mode);
 395
 396         lock_mode = 0;
 397
 398         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
 399         if (error)
 400                 goto out_destroy_fork;
 401
 402         lock_mode = XFS_ILOCK_EXCL;
 403         xfs_ilock(dp, lock_mode);
 404
 405         if (!XFS_IFORK_Q(dp))
 406                 goto out_cancel;
 407
 408         /*
 409          * No need to make quota reservations here. We expect to release some
 410          * blocks, not allocate, in the common case.
 411          */
 412         xfs_trans_ijoin(trans, dp, 0);
 413
 414         /*
 415          * Invalidate and truncate the attribute fork extents. Make sure the
 416          * fork actually has attributes as otherwise the invalidation has no
 417          * blocks to read and returns an error. In this case, just do the fork
 418          * removal below.
 419          */
 420         if (xfs_inode_hasattr(dp) &&
 421             dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
 422                 error = xfs_attr3_root_inactive(&trans, dp);
 423                 if (error)
 424                         goto out_cancel;
 425
 426                 error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
 427                 if (error)
 428                         goto out_cancel;
 429         }
 430
 431         /* Reset the attribute fork - this also destroys the in-core fork */
 432         xfs_attr_fork_remove(dp, trans);
 433
 434         error = xfs_trans_commit(trans);
 435         xfs_iunlock(dp, lock_mode);
 436         return error;
 437
 438 out_cancel:
 439         xfs_trans_cancel(trans);
 440 out_destroy_fork:
 441         /* kill the in-core attr fork before we drop the inode lock */
 442         if (dp->i_afp)
 443                 xfs_idestroy_fork(dp, XFS_ATTR_FORK);
 444         if (lock_mode)
 445                 xfs_iunlock(dp, lock_mode);
 446         return error;
 447 }