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_remote.h"
  19 #include "xfs_trans.h"
  20 #include "xfs_bmap.h"
  21 #include "xfs_attr.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  * Look at all the extents for this logical region,
  29  * invalidate any buffers that are incore/in transactions.
  30  */
  31 STATIC int
  32 xfs_attr3_leaf_freextent(
  33         struct xfs_trans        **trans,
  34         struct xfs_inode        *dp,
  35         xfs_dablk_t             blkno,
  36         int                     blkcnt)
  37 {
  38         struct xfs_bmbt_irec    map;
  39         struct xfs_buf          *bp;
  40         xfs_dablk_t             tblkno;
  41         xfs_daddr_t             dblkno;
  42         int                     tblkcnt;
  43         int                     dblkcnt;
  44         int                     nmap;
  45         int                     error;
  46
  47         /*
  48          * Roll through the "value", invalidating the attribute value's
  49          * blocks.
  50          */
  51         tblkno = blkno;
  52         tblkcnt = blkcnt;
  53         while (tblkcnt > 0) {
  54                 /*
  55                  * Try to remember where we decided to put the value.
  56                  */
  57                 nmap = 1;
  58                 error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
  59                                        &map, &nmap, XFS_BMAPI_ATTRFORK);
  60                 if (error) {
  61                         return error;
  62                 }
  63                 ASSERT(nmap == 1);
  64                 ASSERT(map.br_startblock != DELAYSTARTBLOCK);
  65
  66                 /*
  67                  * If it's a hole, these are already unmapped
  68                  * so there's nothing to invalidate.
  69                  */
  70                 if (map.br_startblock != HOLESTARTBLOCK) {
  71
  72                         dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
  73                                                   map.br_startblock);
  74                         dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
  75                                                 map.br_blockcount);
  76                         bp = xfs_trans_get_buf(*trans,
  77                                         dp->i_mount->m_ddev_targp,
  78                                         dblkno, dblkcnt, 0);
  79                         if (!bp)
  80                                 return -ENOMEM;
  81                         xfs_trans_binval(*trans, bp);
  82                         /*
  83                          * Roll to next transaction.
  84                          */
  85                         error = xfs_trans_roll_inode(trans, dp);
  86                         if (error)
  87                                 return error;
  88                 }
  89
  90                 tblkno += map.br_blockcount;
  91                 tblkcnt -= map.br_blockcount;
  92         }
  93
  94         return 0;
  95 }
  96
  97 /*
  98  * Invalidate all of the "remote" value regions pointed to by a particular
  99  * leaf block.
 100  * Note that we must release the lock on the buffer so that we are not
 101  * caught holding something that the logging code wants to flush to disk.
 102  */
 103 STATIC int
 104 xfs_attr3_leaf_inactive(
 105         struct xfs_trans        **trans,
 106         struct xfs_inode        *dp,
 107         struct xfs_buf          *bp)
 108 {
 109         struct xfs_attr_leafblock *leaf;
 110         struct xfs_attr3_icleaf_hdr ichdr;
 111         struct xfs_attr_leaf_entry *entry;
 112         struct xfs_attr_leaf_name_remote *name_rmt;
 113         struct xfs_attr_inactive_list *list;
 114         struct xfs_attr_inactive_list *lp;
 115         int                     error;
 116         int                     count;
 117         int                     size;
 118         int                     tmp;
 119         int                     i;
 120         struct xfs_mount        *mp = bp->b_mount;
 121
 122         leaf = bp->b_addr;
 123         xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);
 124
 125         /*
 126          * Count the number of "remote" value extents.
 127          */
 128         count = 0;
 129         entry = xfs_attr3_leaf_entryp(leaf);
 130         for (i = 0; i < ichdr.count; entry++, i++) {
 131                 if (be16_to_cpu(entry->nameidx) &&
 132                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 133                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 134                         if (name_rmt->valueblk)
 135                                 count++;
 136                 }
 137         }
 138
 139         /*
 140          * If there are no "remote" values, we're done.
 141          */
 142         if (count == 0) {
 143                 xfs_trans_brelse(*trans, bp);
 144                 return 0;
 145         }
 146
 147         /*
 148          * Allocate storage for a list of all the "remote" value extents.
 149          */
 150         size = count * sizeof(xfs_attr_inactive_list_t);
 151         list = kmem_alloc(size, 0);
 152
 153         /*
 154          * Identify each of the "remote" value extents.
 155          */
 156         lp = list;
 157         entry = xfs_attr3_leaf_entryp(leaf);
 158         for (i = 0; i < ichdr.count; entry++, i++) {
 159                 if (be16_to_cpu(entry->nameidx) &&
 160                     ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
 161                         name_rmt = xfs_attr3_leaf_name_remote(leaf, i);
 162                         if (name_rmt->valueblk) {
 163                                 lp->valueblk = be32_to_cpu(name_rmt->valueblk);
 164                                 lp->valuelen = xfs_attr3_rmt_blocks(dp->i_mount,
 165                                                     be32_to_cpu(name_rmt->valuelen));
 166                                 lp++;
 167                         }
 168                 }
 169         }
 170         xfs_trans_brelse(*trans, bp);   /* unlock for trans. in freextent() */
 171
 172         /*
 173          * Invalidate each of the "remote" value extents.
 174          */
 175         error = 0;
 176         for (lp = list, i = 0; i < count; i++, lp++) {
 177                 tmp = xfs_attr3_leaf_freextent(trans, dp,
 178                                 lp->valueblk, lp->valuelen);
 179
 180                 if (error == 0)
 181                         error = tmp;    /* save only the 1st errno */
 182         }
 183
 184         kmem_free(list);
 185         return error;
 186 }
 187
 188 /*
 189  * Recurse (gasp!) through the attribute nodes until we find leaves.
 190  * We're doing a depth-first traversal in order to invalidate everything.
 191  */
 192 STATIC int
 193 xfs_attr3_node_inactive(
 194         struct xfs_trans        **trans,
 195         struct xfs_inode        *dp,
 196         struct xfs_buf          *bp,
 197         int                     level)
 198 {
 199         struct xfs_mount        *mp = dp->i_mount;
 200         struct xfs_da_blkinfo   *info;
 201         xfs_dablk_t             child_fsb;
 202         xfs_daddr_t             parent_blkno, child_blkno;
 203         struct xfs_buf          *child_bp;
 204         struct xfs_da3_icnode_hdr ichdr;
 205         int                     error, i;
 206
 207         /*
 208          * Since this code is recursive (gasp!) we must protect ourselves.
 209          */
 210         if (level > XFS_DA_NODE_MAXDEPTH) {
 211                 xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 212                 xfs_buf_corruption_error(bp);
 213                 return -EFSCORRUPTED;
 214         }
 215
 216         xfs_da3_node_hdr_from_disk(dp->i_mount, &ichdr, bp->b_addr);
 217         parent_blkno = bp->b_bn;
 218         if (!ichdr.count) {
 219                 xfs_trans_brelse(*trans, bp);
 220                 return 0;
 221         }
 222         child_fsb = be32_to_cpu(ichdr.btree[0].before);
 223         xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
 224
 225         /*
 226          * If this is the node level just above the leaves, simply loop
 227          * over the leaves removing all of them.  If this is higher up
 228          * in the tree, recurse downward.
 229          */
 230         for (i = 0; i < ichdr.count; i++) {
 231                 /*
 232                  * Read the subsidiary block to see what we have to work with.
 233                  * Don't do this in a transaction.  This is a depth-first
 234                  * traversal of the tree so we may deal with many blocks
 235                  * before we come back to this one.
 236                  */
 237                 error = xfs_da3_node_read(*trans, dp, child_fsb, &child_bp,
 238                                           XFS_ATTR_FORK);
 239                 if (error)
 240                         return error;
 241
 242                 /* save for re-read later */
 243                 child_blkno = XFS_BUF_ADDR(child_bp);
 244
 245                 /*
 246                  * Invalidate the subtree, however we have to.
 247                  */
 248                 info = child_bp->b_addr;
 249                 switch (info->magic) {
 250                 case cpu_to_be16(XFS_DA_NODE_MAGIC):
 251                 case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 252                         error = xfs_attr3_node_inactive(trans, dp, child_bp,
 253                                                         level + 1);
 254                         break;
 255                 case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 256                 case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 257                         error = xfs_attr3_leaf_inactive(trans, dp, child_bp);
 258                         break;
 259                 default:
 260                         xfs_buf_corruption_error(child_bp);
 261                         xfs_trans_brelse(*trans, child_bp);
 262                         error = -EFSCORRUPTED;
 263                         break;
 264                 }
 265                 if (error)
 266                         return error;
 267
 268                 /*
 269                  * Remove the subsidiary block from the cache and from the log.
 270                  */
 271                 child_bp = xfs_trans_get_buf(*trans, mp->m_ddev_targp,
 272                                 child_blkno,
 273                                 XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0);
 274                 if (!child_bp)
 275                         return -EIO;
 276                 error = bp->b_error;
 277                 if (error) {
 278                         xfs_trans_brelse(*trans, child_bp);
 279                         return error;
 280                 }
 281                 xfs_trans_binval(*trans, child_bp);
 282
 283                 /*
 284                  * If we're not done, re-read the parent to get the next
 285                  * child block number.
 286                  */
 287                 if (i + 1 < ichdr.count) {
 288                         struct xfs_da3_icnode_hdr phdr;
 289
 290                         error = xfs_da3_node_read_mapped(*trans, dp,
 291                                         parent_blkno, &bp, XFS_ATTR_FORK);
 292                         if (error)
 293                                 return error;
 294                         xfs_da3_node_hdr_from_disk(dp->i_mount, &phdr,
 295                                                   bp->b_addr);
 296                         child_fsb = be32_to_cpu(phdr.btree[i + 1].before);
 297                         xfs_trans_brelse(*trans, bp);
 298                 }
 299                 /*
 300                  * Atomically commit the whole invalidate stuff.
 301                  */
 302                 error = xfs_trans_roll_inode(trans, dp);
 303                 if (error)
 304                         return  error;
 305         }
 306
 307         return 0;
 308 }
 309
 310 /*
 311  * Indiscriminately delete the entire attribute fork
 312  *
 313  * Recurse (gasp!) through the attribute nodes until we find leaves.
 314  * We're doing a depth-first traversal in order to invalidate everything.
 315  */
 316 static int
 317 xfs_attr3_root_inactive(
 318         struct xfs_trans        **trans,
 319         struct xfs_inode        *dp)
 320 {
 321         struct xfs_mount        *mp = dp->i_mount;
 322         struct xfs_da_blkinfo   *info;
 323         struct xfs_buf          *bp;
 324         xfs_daddr_t             blkno;
 325         int                     error;
 326
 327         /*
 328          * Read block 0 to see what we have to work with.
 329          * We only get here if we have extents, since we remove
 330          * the extents in reverse order the extent containing
 331          * block 0 must still be there.
 332          */
 333         error = xfs_da3_node_read(*trans, dp, 0, &bp, XFS_ATTR_FORK);
 334         if (error)
 335                 return error;
 336         blkno = bp->b_bn;
 337
 338         /*
 339          * Invalidate the tree, even if the "tree" is only a single leaf block.
 340          * This is a depth-first traversal!
 341          */
 342         info = bp->b_addr;
 343         switch (info->magic) {
 344         case cpu_to_be16(XFS_DA_NODE_MAGIC):
 345         case cpu_to_be16(XFS_DA3_NODE_MAGIC):
 346                 error = xfs_attr3_node_inactive(trans, dp, bp, 1);
 347                 break;
 348         case cpu_to_be16(XFS_ATTR_LEAF_MAGIC):
 349         case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
 350                 error = xfs_attr3_leaf_inactive(trans, dp, bp);
 351                 break;
 352         default:
 353                 error = -EFSCORRUPTED;
 354                 xfs_buf_corruption_error(bp);
 355                 xfs_trans_brelse(*trans, bp);
 356                 break;
 357         }
 358         if (error)
 359                 return error;
 360
 361         /*
 362          * Invalidate the incore copy of the root block.
 363          */
 364         bp = xfs_trans_get_buf(*trans, mp->m_ddev_targp, blkno,
 365                         XFS_FSB_TO_BB(mp, mp->m_attr_geo->fsbcount), 0);
 366         if (!bp)
 367                 return -EIO;
 368         error = bp->b_error;
 369         if (error) {
 370                 xfs_trans_brelse(*trans, bp);
 371                 return error;
 372         }
 373         xfs_trans_binval(*trans, bp);   /* remove from cache */
 374         /*
 375          * Commit the invalidate and start the next transaction.
 376          */
 377         error = xfs_trans_roll_inode(trans, dp);
 378
 379         return error;
 380 }
 381
 382 /*
 383  * xfs_attr_inactive kills all traces of an attribute fork on an inode. It
 384  * removes both the on-disk and in-memory inode fork. Note that this also has to
 385  * handle the condition of inodes without attributes but with an attribute fork
 386  * configured, so we can't use xfs_inode_hasattr() here.
 387  *
 388  * The in-memory attribute fork is removed even on error.
 389  */
 390 int
 391 xfs_attr_inactive(
 392         struct xfs_inode        *dp)
 393 {
 394         struct xfs_trans        *trans;
 395         struct xfs_mount        *mp;
 396         int                     lock_mode = XFS_ILOCK_SHARED;
 397         int                     error = 0;
 398
 399         mp = dp->i_mount;
 400         ASSERT(! XFS_NOT_DQATTACHED(mp, dp));
 401
 402         xfs_ilock(dp, lock_mode);
 403         if (!XFS_IFORK_Q(dp))
 404                 goto out_destroy_fork;
 405         xfs_iunlock(dp, lock_mode);
 406
 407         lock_mode = 0;
 408
 409         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_attrinval, 0, 0, 0, &trans);
 410         if (error)
 411                 goto out_destroy_fork;
 412
 413         lock_mode = XFS_ILOCK_EXCL;
 414         xfs_ilock(dp, lock_mode);
 415
 416         if (!XFS_IFORK_Q(dp))
 417                 goto out_cancel;
 418
 419         /*
 420          * No need to make quota reservations here. We expect to release some
 421          * blocks, not allocate, in the common case.
 422          */
 423         xfs_trans_ijoin(trans, dp, 0);
 424
 425         /*
 426          * Invalidate and truncate the attribute fork extents. Make sure the
 427          * fork actually has attributes as otherwise the invalidation has no
 428          * blocks to read and returns an error. In this case, just do the fork
 429          * removal below.
 430          */
 431         if (xfs_inode_hasattr(dp) &&
 432             dp->i_d.di_aformat != XFS_DINODE_FMT_LOCAL) {
 433                 error = xfs_attr3_root_inactive(&trans, dp);
 434                 if (error)
 435                         goto out_cancel;
 436
 437                 error = xfs_itruncate_extents(&trans, dp, XFS_ATTR_FORK, 0);
 438                 if (error)
 439                         goto out_cancel;
 440         }
 441
 442         /* Reset the attribute fork - this also destroys the in-core fork */
 443         xfs_attr_fork_remove(dp, trans);
 444
 445         error = xfs_trans_commit(trans);
 446         xfs_iunlock(dp, lock_mode);
 447         return error;
 448
 449 out_cancel:
 450         xfs_trans_cancel(trans);
 451 out_destroy_fork:
 452         /* kill the in-core attr fork before we drop the inode lock */
 453         if (dp->i_afp)
 454                 xfs_idestroy_fork(dp, XFS_ATTR_FORK);
 455         if (lock_mode)
 456                 xfs_iunlock(dp, lock_mode);
 457         return error;
 458 }