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_attr.h"
  19 #include "xfs_attr_remote.h"
  20 #include "xfs_trans.h"
  21 #include "xfs_bmap.h"
  22 #include "xfs_attr_leaf.h"
  23 #include "xfs_quota.h"
  24 #include "xfs_dir2.h"
  25 #include "xfs_error.h"
  26
  27 /*
  28  * Invalidate any incore buffers associated with this remote attribute value
  29  * extent.   We never log remote attribute value buffers, which means that they
  30  * won't be attached to a transaction and are therefore safe to mark stale.
  31  * The actual bunmapi will be taken care of later.
  32  */
  33 STATIC int
  34 xfs_attr3_rmt_stale(
  35         struct xfs_inode        *dp,
  36         xfs_dablk_t             blkno,
  37         int                     blkcnt)
  38 {
  39         struct xfs_bmbt_irec    map;
  40         int                     nmap;
  41         int                     error;
  42
  43         /*
  44          * Roll through the "value", invalidating the attribute value's
  45          * blocks.
  46          */
  47         while (blkcnt > 0) {
  48                 /*
  49                  * Try to remember where we decided to put the value.
  50                  */
  51                 nmap = 1;
  52                 error = xfs_bmapi_read(dp, (xfs_fileoff_t)blkno, blkcnt,
  53                                        &map, &nmap, XFS_BMAPI_ATTRFORK);
  54                 if (error)
  55                         return error;
  56                 if (XFS_IS_CORRUPT(dp->i_mount, nmap != 1))
  57                         return -EFSCORRUPTED;
  58
  59                 /*
  60                  * Mark any incore buffers for the remote value as stale.  We
  61                  * never log remote attr value buffers, so the buffer should be
  62                  * easy to kill.
  63                  */
  64                 error = xfs_attr_rmtval_stale(dp, &map, 0);
  65                 if (error)
  66                         return error;
  67
  68                 blkno += map.br_blockcount;
  69                 blkcnt -= map.br_blockcount;
  70         }
  71
  72         return 0;
  73 }
  74
  75 /*
  76  * Invalidate all of the "remote" value regions pointed to by a particular
  77  * leaf block.
  78  * Note that we must release the lock on the buffer so that we are not
  79  * caught holding something that the logging code wants to flush to disk.
  80  */
  81 STATIC int
  82 xfs_attr3_leaf_inactive(
  83         struct xfs_trans                **trans,
  84         struct xfs_inode                *dp,
  85         struct xfs_buf                  *bp)
  86 {
  87         struct xfs_attr3_icleaf_hdr     ichdr;
  88         struct xfs_mount                *mp = bp->b_mount;
  89         struct xfs_attr_leafblock       *leaf = bp->b_addr;
  90         struct xfs_attr_leaf_entry      *entry;
  91         struct xfs_attr_leaf_name_remote *name_rmt;
  92         int                             error = 0;
  93         int                             i;
  94
  95         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
  96
  97         /*
  98          * Find the remote value extents for this leaf and invalidate their
  99          * incore buffers.
 100          */
 101         entry = xfs_attr3_leaf_entryp(leaf);
 102         for (i = 0; i < ichdr.count; entry++, i++) {
 103                 int             blkcnt;
 104
 105                 if (!entry->nameidx || (entry->flags & XFS_ATTR_LOCAL))
 106                         continue;
 107
 108                 name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 109                 if (!name_rmt->valueblk)
 110                         continue;
 111
 112                 blkcnt = xfs_attr3_rmt_blocks(dp->i_mount,
 113                                 be32_to_cpu(name_rmt->valuelen));
 114                 error = xfs_attr3_rmt_stale(dp,
 115                                 be32_to_cpu(name_rmt->valueblk), blkcnt);
 116                 if (error)
 117                         goto err;
 118         }
 119
 120         xfs_trans_brelse(*trans, bp);
 121 err:
 122         return error;
 123 }
 124
 125 /*
 126  * Recurse (gasp!) through the attribute nodes until we find leaves.
 127  * We're doing a depth-first traversal in order to invalidate everything.
 128  */
 129 STATIC int
 130 xfs_attr3_node_inactive(
 131         struct xfs_trans        **trans,
 132         struct xfs_inode        *dp,
 133         struct xfs_buf          *bp,
 134         int                     level)
 135 {
 136         struct xfs_mount        *mp = dp->i_mount;
 137         struct xfs_da_blkinfo   *info;
 138         xfs_dablk_t             child_fsb;
 139         xfs_daddr_t             parent_blkno, child_blkno;
 140         struct xfs_buf          *child_bp;
 141         struct xfs_da3_icnode_hdr ichdr;
 142         int                     error, i;
 143
 144         /*
 145          * Since this code is recursive (gasp!) we must protect ourselves.
 146          */
 147         if (level > XFS_DA_NODE_MAXDEPTH) {
 148                 xfs_buf_mark_corrupt(bp);
 149                 xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 150                 return -EFSCORRUPTED;
 151         }
 152
 153         xfs_da3_node_hdr_from_disk(dp->i_mount, &ichdr, bp->b_addr);
 154         parent_blkno = xfs_buf_daddr(bp);
 155         if (!ichdr.count) {
 156                 xfs_trans_brelse(*trans, bp);
 157                 return 0;
 158         }
 159         child_fsb = be32_to_cpu(ichdr.btree[0].before);
 160         xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 161
 162         /*
 163          * If this is the node level just above the leaves, simply loop
 164          * over the leaves removing all of them.  If this is higher up
 165          * in the tree, recurse downward.
 166          */
 167         for (i = 0; i < ichdr.count; i++) {
 168                 /*
 169                  * Read the subsidiary block to see what we have to work with.
 170                  * Don't do this in a transaction.  This is a depth-first
 171                  * traversal of the tree so we may deal with many blocks
 172                  * before we come back to this one.
 173                  */
 174                 error = xfs_da3_node_read(*trans, dp, child_fsb, &child_bp,
 175                                           XFS_ATTR_FORK);
 176                 if (error)
 177                         return error;
 178
 179                 /* save for re-read later */
 180                 child_blkno = xfs_buf_daddr(child_bp);
 181
 182                 /*
 183                  * Invalidate the subtree, however we have to.
 184                  */
 185                 info = child_bp->b_addr;
 186                 switch (info->magic) {
 187                 case cpu_to_be16(XFS_DA_NODE_MAGIC):
 188                 case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 189                         error = xfs_attr3_node_inactive(trans, dp, child_bp,
 190                                                         level + 1);
 191                         break;
 192                 case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 193                 case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 194                         error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
 195                         break;
 196                 default:
 197                         xfs_buf_mark_corrupt(child_bp);
 198                         xfs_trans_brelse(*trans, child_bp);
 199                         error = -EFSCORRUPTED;
 200                         break;
 201                 }
 202                 if (error)
 203                         return error;
 204
 205                 /*
 206                  * Remove the subsidiary block from the cache and from the log.
 207                  */
 208                 error = xfs_trans_get_buf(*trans, mp->m_ddev_targp,
 209                                 child_blkno,
 210                                 XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0,
 211                                 &child_bp);
 212                 if (error)
 213                         return error;
 214                 error = bp->b_error;
 215                 if (error) {
 216                         xfs_trans_brelse(*trans, child_bp);
 217                         return error;
 218                 }
 219                 xfs_trans_binval(*trans, child_bp);
 220
 221                 /*
 222                  * If we're not done, re-read the parent to get the next
 223                  * child block number.
 224                  */
 225                 if (i + 1 < ichdr.count) {
 226                         struct xfs_da3_icnode_hdr phdr;
 227
 228                         error = xfs_da3_node_read_mapped(*trans, dp,
 229                                         parent_blkno, &bp, XFS_ATTR_FORK);
 230                         if (error)
 231                                 return error;
 232                         xfs_da3_node_hdr_from_disk(dp->i_mount, &phdr,
 233                                                   bp->b_addr);
 234                         child_fsb = be32_to_cpu(phdr.btree[i + 1].before);
 235                         xfs_trans_brelse(*trans, bp);
 236                 }
 237                 /*
 238                  * Atomically commit the whole invalidate stuff.
 239                  */
 240                 error = xfs_trans_roll_inode(trans, dp);
 241                 if (error)
 242                         return  error;
 243         }
 244
 245         return 0;
 246 }
 247
 248 /*
 249  * Indiscriminately delete the entire attribute fork
 250  *
 251  * Recurse (gasp!) through the attribute nodes until we find leaves.
 252  * We're doing a depth-first traversal in order to invalidate everything.
 253  */
 254 static int
 255 xfs_attr3_root_inactive(
 256         struct xfs_trans        **trans,
 257         struct xfs_inode        *dp)
 258 {
 259         struct xfs_mount        *mp = dp->i_mount;
 260         struct xfs_da_blkinfo   *info;
 261         struct xfs_buf          *bp;
 262         xfs_daddr_t             blkno;
 263         int                     error;
 264
 265         /*
 266          * Read block 0 to see what we have to work with.
 267          * We only get here if we have extents, since we remove
 268          * the extents in reverse order the extent containing
 269          * block 0 must still be there.
 270          */
 271         error = xfs_da3_node_read(*trans, dp, 0, &bp, XFS_ATTR_FORK);
 272         if (error)
 273                 return error;
 274         blkno = xfs_buf_daddr(bp);
 275
 276         /*
 277          * Invalidate the tree, even if the "tree" is only a single leaf block.
 278          * This is a depth-first traversal!
 279          */
 280         info = bp->b_addr;
 281         switch (info->magic) {
 282         case cpu_to_be16(XFS_DA_NODE_MAGIC):
 283         case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 284                 error = xfs_attr3_node_inactive(trans, dp, bp, 1);
 285                 break;
 286         case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 287         case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 288                 error = xfs_attr3_leaf_inactive(trans, dp, bp);
 289                 break;
 290         default:
 291                 error = -EFSCORRUPTED;
 292                 xfs_buf_mark_corrupt(bp);
 293                 xfs_trans_brelse(*trans, bp);
 294                 break;
 295         }
 296         if (error)
 297                 return error;
 298
 299         /*
 300          * Invalidate the incore copy of the root block.
 301          */
 302         error = xfs_trans_get_buf(*trans, mp->m_ddev_targp, blkno,
 303                         XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0, &bp);
 304         if (error)
 305                 return error;
 306         error = bp->b_error;
 307         if (error) {
 308                 xfs_trans_brelse(*trans, bp);
 309                 return error;
 310         }
 311         xfs_trans_binval(*trans, bp);   /* remove from cache */
 312         /*
 313          * Commit the invalidate and start the next transaction.
 314          */
 315         error = xfs_trans_roll_inode(trans, dp);
 316
 317         return error;
 318 }
 319
 320 /*
 321  * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
 322  * removes both the on-disk and in-memory inode fork. Note that this also has to
 323  * handle the condition of inodes without attributes but with an attribute fork
 324  * configured, so we can't use xfs_inode_hasattr() here.
 325  *
 326  * The in-memory attribute fork is removed even on error.
 327  */
 328 int
 329 xfs_attr_inactive(
 330         struct xfs_inode        *dp)
 331 {
 332         struct xfs_trans        *trans;
 333         struct xfs_mount        *mp;
 334         int                     lock_mode = XFS_ILOCK_SHARED;
 335         int                     error = 0;
 336
 337         mp = dp->i_mount;
 338         ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
 339
 340         xfs_ilock(dp, lock_mode);
 341         if (!XFS_IFORK_Q(dp))
 342                 goto out_destroy_fork;
 343         xfs_iunlock(dp, lock_mode);
 344
 345         lock_mode = 0;
 346
 347         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
 348         if (error)
 349                 goto out_destroy_fork;
 350
 351         lock_mode = XFS_ILOCK_EXCL;
 352         xfs_ilock(dp, lock_mode);
 353
 354         if (!XFS_IFORK_Q(dp))
 355                 goto out_cancel;
 356
 357         /*
 358          * No need to make quota reservations here. We expect to release some
 359          * blocks, not allocate, in the common case.
 360          */
 361         xfs_trans_ijoin(trans, dp, 0);
 362
 363         /*
 364          * Invalidate and truncate the attribute fork extents. Make sure the
 365          * fork actually has attributes as otherwise the invalidation has no
 366          * blocks to read and returns an error. In this case, just do the fork
 367          * removal below.
 368          */
 369         if (xfs_inode_hasattr(dp) &&
 370             dp->i_afp->if_format != XFS_DINODE_FMT_LOCAL) {
 371                 error = xfs_attr3_root_inactive(&trans, dp);
 372                 if (error)
 373                         goto out_cancel;
 374
 375                 error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
 376                 if (error)
 377                         goto out_cancel;
 378         }
 379
 380         /* Reset the attribute fork - this also destroys the in-core fork */
 381         xfs_attr_fork_remove(dp, trans);
 382
 383         error = xfs_trans_commit(trans);
 384         xfs_iunlock(dp, lock_mode);
 385         return error;
 386
 387 out_cancel:
 388         xfs_trans_cancel(trans);
 389 out_destroy_fork:
 390         /* kill the in-core attr fork before we drop the inode lock */
 391         if (dp->i_afp) {
 392                 xfs_idestroy_fork(dp->i_afp);
 393                 kmem_cache_free(xfs_ifork_zone, dp->i_afp);
 394                 dp->i_afp = NULL;
 395         }
 396         if (lock_mode)
 397                 xfs_iunlock(dp, lock_mode);
 398         return error;
 399 }