fs/ubifs/journal.c

   1 /*
   2  * This file is part of UBIFS.
   3  *
   4  * Copyright (C) 2006-2008 Nokia Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 as published by
   8  * the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc., 51
  17  * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  18  *
  19  * Authors: Artem Bityutskiy (Битюцкий Артём)
  20  *          Adrian Hunter
  21  */
  22
  23 /*
  24  * This file implements UBIFS journal.
  25  *
  26  * The journal consists of 2 parts - the log and bud LEBs. The log has fixed
  27  * length and position, while a bud logical eraseblock is any LEB in the main
  28  * area. Buds contain file system data - data nodes, inode nodes, etc. The log
  29  * contains only references to buds and some other stuff like commit
  30  * start node. The idea is that when we commit the journal, we do
  31  * not copy the data, the buds just become indexed. Since after the commit the
  32  * nodes in bud eraseblocks become leaf nodes of the file system index tree, we
  33  * use term "bud". Analogy is obvious, bud eraseblocks contain nodes which will
  34  * become leafs in the future.
  35  *
  36  * The journal is multi-headed because we want to write data to the journal as
  37  * optimally as possible. It is nice to have nodes belonging to the same inode
  38  * in one LEB, so we may write data owned by different inodes to different
  39  * journal heads, although at present only one data head is used.
  40  *
  41  * For recovery reasons, the base head contains all inode nodes, all directory
  42  * entry nodes and all truncate nodes. This means that the other heads contain
  43  * only data nodes.
  44  *
  45  * Bud LEBs may be half-indexed. For example, if the bud was not full at the
  46  * time of commit, the bud is retained to continue to be used in the journal,
  47  * even though the "front" of the LEB is now indexed. In that case, the log
  48  * reference contains the offset where the bud starts for the purposes of the
  49  * journal.
  50  *
  51  * The journal size has to be limited, because the larger is the journal, the
  52  * longer it takes to mount UBIFS (scanning the journal) and the more memory it
  53  * takes (indexing in the TNC).
  54  *
  55  * All the journal write operations like 'ubifs_jnl_update()' here, which write
  56  * multiple UBIFS nodes to the journal at one go, are atomic with respect to
  57  * unclean reboots. Should the unclean reboot happen, the recovery code drops
  58  * all the nodes.
  59  */
  60
  61 #include "ubifs.h"
  62
  63 /**
  64  * zero_ino_node_unused - zero out unused fields of an on-flash inode node.
  65  * @ino: the inode to zero out
  66  */
  67 static inline void zero_ino_node_unused(struct ubifs_ino_node *ino)
  68 {
  69         memset(ino->padding1, 0, 4);
  70         memset(ino->padding2, 0, 26);
  71 }
  72
  73 /**
  74  * zero_dent_node_unused - zero out unused fields of an on-flash directory
  75  *                         entry node.
  76  * @dent: the directory entry to zero out
  77  */
  78 static inline void zero_dent_node_unused(struct ubifs_dent_node *dent)
  79 {
  80         dent->padding1 = 0;
  81         memset(dent->padding2, 0, 4);
  82 }
  83
  84 /**
  85  * zero_data_node_unused - zero out unused fields of an on-flash data node.
  86  * @data: the data node to zero out
  87  */
  88 static inline void zero_data_node_unused(struct ubifs_data_node *data)
  89 {
  90         memset(data->padding, 0, 2);
  91 }
  92
  93 /**
  94  * zero_trun_node_unused - zero out unused fields of an on-flash truncation
  95  *                         node.
  96  * @trun: the truncation node to zero out
  97  */
  98 static inline void zero_trun_node_unused(struct ubifs_trun_node *trun)
  99 {
 100         memset(trun->padding, 0, 12);
 101 }
 102
 103 /**
 104  * reserve_space - reserve space in the journal.
 105  * @c: UBIFS file-system description object
 106  * @jhead: journal head number
 107  * @len: node length
 108  *
 109  * This function reserves space in journal head @head. If the reservation
 110  * succeeded, the journal head stays locked and later has to be unlocked using
 111  * 'release_head()'. 'write_node()' and 'write_head()' functions also unlock
 112  * it. Returns zero in case of success, %-EAGAIN if commit has to be done, and
 113  * other negative error codes in case of other failures.
 114  */
 115 static int reserve_space(struct ubifs_info *c, int jhead, int len)
 116 {
 117         int err = 0, err1, retries = 0, avail, lnum, offs, free, squeeze;
 118         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 119
 120         /*
 121          * Typically, the base head has smaller nodes written to it, so it is
 122          * better to try to allocate space at the ends of eraseblocks. This is
 123          * what the squeeze parameter does.
 124          */
 125         squeeze = (jhead == BASEHD);
 126 again:
 127         mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 128
 129         if (c->ro_media) {
 130                 err = -EROFS;
 131                 goto out_unlock;
 132         }
 133
 134         avail = c->leb_size - wbuf->offs - wbuf->used;
 135         if (wbuf->lnum != -1 && avail >= len)
 136                 return 0;
 137
 138         /*
 139          * Write buffer wasn't seek'ed or there is no enough space - look for an
 140          * LEB with some empty space.
 141          */
 142         lnum = ubifs_find_free_space(c, len, &free, squeeze);
 143         if (lnum >= 0) {
 144                 /* Found an LEB, add it to the journal head */
 145                 offs = c->leb_size - free;
 146                 err = ubifs_add_bud_to_log(c, jhead, lnum, offs);
 147                 if (err)
 148                         goto out_return;
 149                 /* A new bud was successfully allocated and added to the log */
 150                 goto out;
 151         }
 152
 153         err = lnum;
 154         if (err != -ENOSPC)
 155                 goto out_unlock;
 156
 157         /*
 158          * No free space, we have to run garbage collector to make
 159          * some. But the write-buffer mutex has to be unlocked because
 160          * GC also takes it.
 161          */
 162         dbg_jnl("no free space  jhead %d, run GC", jhead);
 163         mutex_unlock(&wbuf->io_mutex);
 164
 165         lnum = ubifs_garbage_collect(c, 0);
 166         if (lnum < 0) {
 167                 err = lnum;
 168                 if (err != -ENOSPC)
 169                         return err;
 170
 171                 /*
 172                  * GC could not make a free LEB. But someone else may
 173                  * have allocated new bud for this journal head,
 174                  * because we dropped @wbuf->io_mutex, so try once
 175                  * again.
 176                  */
 177                 dbg_jnl("GC couldn't make a free LEB for jhead %d", jhead);
 178                 if (retries++ < 2) {
 179                         dbg_jnl("retry (%d)", retries);
 180                         goto again;
 181                 }
 182
 183                 dbg_jnl("return -ENOSPC");
 184                 return err;
 185         }
 186
 187         mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 188         dbg_jnl("got LEB %d for jhead %d", lnum, jhead);
 189         avail = c->leb_size - wbuf->offs - wbuf->used;
 190
 191         if (wbuf->lnum != -1 && avail >= len) {
 192                 /*
 193                  * Someone else has switched the journal head and we have
 194                  * enough space now. This happens when more then one process is
 195                  * trying to write to the same journal head at the same time.
 196                  */
 197                 dbg_jnl("return LEB %d back, already have LEB %d:%d",
 198                         lnum, wbuf->lnum, wbuf->offs + wbuf->used);
 199                 err = ubifs_return_leb(c, lnum);
 200                 if (err)
 201                         goto out_unlock;
 202                 return 0;
 203         }
 204
 205         err = ubifs_add_bud_to_log(c, jhead, lnum, 0);
 206         if (err)
 207                 goto out_return;
 208         offs = 0;
 209
 210 out:
 211         err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs, UBI_SHORTTERM);
 212         if (err)
 213                 goto out_unlock;
 214
 215         return 0;
 216
 217 out_unlock:
 218         mutex_unlock(&wbuf->io_mutex);
 219         return err;
 220
 221 out_return:
 222         /* An error occurred and the LEB has to be returned to lprops */
 223         ubifs_assert(err < 0);
 224         err1 = ubifs_return_leb(c, lnum);
 225         if (err1 && err == -EAGAIN)
 226                 /*
 227                  * Return original error code only if it is not %-EAGAIN,
 228                  * which is not really an error. Otherwise, return the error
 229                  * code of 'ubifs_return_leb()'.
 230                  */
 231                 err = err1;
 232         mutex_unlock(&wbuf->io_mutex);
 233         return err;
 234 }
 235
 236 /**
 237  * write_node - write node to a journal head.
 238  * @c: UBIFS file-system description object
 239  * @jhead: journal head
 240  * @node: node to write
 241  * @len: node length
 242  * @lnum: LEB number written is returned here
 243  * @offs: offset written is returned here
 244  *
 245  * This function writes a node to reserved space of journal head @jhead.
 246  * Returns zero in case of success and a negative error code in case of
 247  * failure.
 248  */
 249 static int write_node(struct ubifs_info *c, int jhead, void *node, int len,
 250                       int *lnum, int *offs)
 251 {
 252         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 253
 254         ubifs_assert(jhead != GCHD);
 255
 256         *lnum = c->jheads[jhead].wbuf.lnum;
 257         *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 258
 259         dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len);
 260         ubifs_prepare_node(c, node, len, 0);
 261
 262         return ubifs_wbuf_write_nolock(wbuf, node, len);
 263 }
 264
 265 /**
 266  * write_head - write data to a journal head.
 267  * @c: UBIFS file-system description object
 268  * @jhead: journal head
 269  * @buf: buffer to write
 270  * @len: length to write
 271  * @lnum: LEB number written is returned here
 272  * @offs: offset written is returned here
 273  * @sync: non-zero if the write-buffer has to by synchronized
 274  *
 275  * This function is the same as 'write_node()' but it does not assume the
 276  * buffer it is writing is a node, so it does not prepare it (which means
 277  * initializing common header and calculating CRC).
 278  */
 279 static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
 280                       int *lnum, int *offs, int sync)
 281 {
 282         int err;
 283         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 284
 285         ubifs_assert(jhead != GCHD);
 286
 287         *lnum = c->jheads[jhead].wbuf.lnum;
 288         *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 289         dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len);
 290
 291         err = ubifs_wbuf_write_nolock(wbuf, buf, len);
 292         if (err)
 293                 return err;
 294         if (sync)
 295                 err = ubifs_wbuf_sync_nolock(wbuf);
 296         return err;
 297 }
 298
 299 /**
 300  * make_reservation - reserve journal space.
 301  * @c: UBIFS file-system description object
 302  * @jhead: journal head
 303  * @len: how many bytes to reserve
 304  *
 305  * This function makes space reservation in journal head @jhead. The function
 306  * takes the commit lock and locks the journal head, and the caller has to
 307  * unlock the head and finish the reservation with 'finish_reservation()'.
 308  * Returns zero in case of success and a negative error code in case of
 309  * failure.
 310  *
 311  * Note, the journal head may be unlocked as soon as the data is written, while
 312  * the commit lock has to be released after the data has been added to the
 313  * TNC.
 314  */
 315 static int make_reservation(struct ubifs_info *c, int jhead, int len)
 316 {
 317         int err, cmt_retries = 0, nospc_retries = 0;
 318
 319 again:
 320         down_read(&c->commit_sem);
 321         err = reserve_space(c, jhead, len);
 322         if (!err)
 323                 return 0;
 324         up_read(&c->commit_sem);
 325
 326         if (err == -ENOSPC) {
 327                 /*
 328                  * GC could not make any progress. We should try to commit
 329                  * once because it could make some dirty space and GC would
 330                  * make progress, so make the error -EAGAIN so that the below
 331                  * will commit and re-try.
 332                  */
 333                 if (nospc_retries++ < 2) {
 334                         dbg_jnl("no space, retry");
 335                         err = -EAGAIN;
 336                 }
 337
 338                 /*
 339                  * This means that the budgeting is incorrect. We always have
 340                  * to be able to write to the media, because all operations are
 341                  * budgeted. Deletions are not budgeted, though, but we reserve
 342                  * an extra LEB for them.
 343                  */
 344         }
 345
 346         if (err != -EAGAIN)
 347                 goto out;
 348
 349         /*
 350          * -EAGAIN means that the journal is full or too large, or the above
 351          * code wants to do one commit. Do this and re-try.
 352          */
 353         if (cmt_retries > 128) {
 354                 /*
 355                  * This should not happen unless the journal size limitations
 356                  * are too tough.
 357                  */
 358                 ubifs_err("stuck in space allocation");
 359                 err = -ENOSPC;
 360                 goto out;
 361         } else if (cmt_retries > 32)
 362                 ubifs_warn("too many space allocation re-tries (%d)",
 363                            cmt_retries);
 364
 365         dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
 366                 cmt_retries);
 367         cmt_retries += 1;
 368
 369         err = ubifs_run_commit(c);
 370         if (err)
 371                 return err;
 372         goto again;
 373
 374 out:
 375         ubifs_err("cannot reserve %d bytes in jhead %d, error %d",
 376                   len, jhead, err);
 377         if (err == -ENOSPC) {
 378                 /* This are some budgeting problems, print useful information */
 379                 down_write(&c->commit_sem);
 380                 spin_lock(&c->space_lock);
 381                 dbg_dump_stack();
 382                 dbg_dump_budg(c);
 383                 spin_unlock(&c->space_lock);
 384                 dbg_dump_lprops(c);
 385                 cmt_retries = dbg_check_lprops(c);
 386                 up_write(&c->commit_sem);
 387         }
 388         return err;
 389 }
 390
 391 /**
 392  * release_head - release a journal head.
 393  * @c: UBIFS file-system description object
 394  * @jhead: journal head
 395  *
 396  * This function releases journal head @jhead which was locked by
 397  * the 'make_reservation()' function. It has to be called after each successful
 398  * 'make_reservation()' invocation.
 399  */
 400 static inline void release_head(struct ubifs_info *c, int jhead)
 401 {
 402         mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
 403 }
 404
 405 /**
 406  * finish_reservation - finish a reservation.
 407  * @c: UBIFS file-system description object
 408  *
 409  * This function finishes journal space reservation. It must be called after
 410  * 'make_reservation()'.
 411  */
 412 static void finish_reservation(struct ubifs_info *c)
 413 {
 414         up_read(&c->commit_sem);
 415 }
 416
 417 /**
 418  * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
 419  * @mode: inode mode
 420  */
 421 static int get_dent_type(int mode)
 422 {
 423         switch (mode & S_IFMT) {
 424         case S_IFREG:
 425                 return UBIFS_ITYPE_REG;
 426         case S_IFDIR:
 427                 return UBIFS_ITYPE_DIR;
 428         case S_IFLNK:
 429                 return UBIFS_ITYPE_LNK;
 430         case S_IFBLK:
 431                 return UBIFS_ITYPE_BLK;
 432         case S_IFCHR:
 433                 return UBIFS_ITYPE_CHR;
 434         case S_IFIFO:
 435                 return UBIFS_ITYPE_FIFO;
 436         case S_IFSOCK:
 437                 return UBIFS_ITYPE_SOCK;
 438         default:
 439                 BUG();
 440         }
 441         return 0;
 442 }
 443
 444 /**
 445  * pack_inode - pack an inode node.
 446  * @c: UBIFS file-system description object
 447  * @ino: buffer in which to pack inode node
 448  * @inode: inode to pack
 449  * @last: indicates the last node of the group
 450  * @last_reference: non-zero if this is a deletion inode
 451  */
 452 static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
 453                        const struct inode *inode, int last,
 454                        int last_reference)
 455 {
 456         int data_len = 0;
 457         struct ubifs_inode *ui = ubifs_inode(inode);
 458
 459         ino->ch.node_type = UBIFS_INO_NODE;
 460         ino_key_init_flash(c, &ino->key, inode->i_ino);
 461         ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum);
 462         ino->atime_sec  = cpu_to_le64(inode->i_atime.tv_sec);
 463         ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
 464         ino->ctime_sec  = cpu_to_le64(inode->i_ctime.tv_sec);
 465         ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 466         ino->mtime_sec  = cpu_to_le64(inode->i_mtime.tv_sec);
 467         ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 468         ino->uid   = cpu_to_le32(inode->i_uid);
 469         ino->gid   = cpu_to_le32(inode->i_gid);
 470         ino->mode  = cpu_to_le32(inode->i_mode);
 471         ino->flags = cpu_to_le32(ui->flags);
 472         ino->size  = cpu_to_le64(ui->ui_size);
 473         ino->nlink = cpu_to_le32(inode->i_nlink);
 474         ino->compr_type  = cpu_to_le16(ui->compr_type);
 475         ino->data_len    = cpu_to_le32(ui->data_len);
 476         ino->xattr_cnt   = cpu_to_le32(ui->xattr_cnt);
 477         ino->xattr_size  = cpu_to_le32(ui->xattr_size);
 478         ino->xattr_names = cpu_to_le32(ui->xattr_names);
 479         zero_ino_node_unused(ino);
 480
 481         /*
 482          * Drop the attached data if this is a deletion inode, the data is not
 483          * needed anymore.
 484          */
 485         if (!last_reference) {
 486                 memcpy(ino->data, ui->data, ui->data_len);
 487                 data_len = ui->data_len;
 488         }
 489
 490         ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last);
 491 }
 492
 493 /**
 494  * mark_inode_clean - mark UBIFS inode as clean.
 495  * @c: UBIFS file-system description object
 496  * @ui: UBIFS inode to mark as clean
 497  *
 498  * This helper function marks UBIFS inode @ui as clean by cleaning the
 499  * @ui->dirty flag and releasing its budget. Note, VFS may still treat the
 500  * inode as dirty and try to write it back, but 'ubifs_write_inode()' would
 501  * just do nothing.
 502  */
 503 static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui)
 504 {
 505         if (ui->dirty)
 506                 ubifs_release_dirty_inode_budget(c, ui);
 507         ui->dirty = 0;
 508 }
 509
 510 /**
 511  * ubifs_jnl_update - update inode.
 512  * @c: UBIFS file-system description object
 513  * @dir: parent inode or host inode in case of extended attributes
 514  * @nm: directory entry name
 515  * @inode: inode to update
 516  * @deletion: indicates a directory entry deletion i.e unlink or rmdir
 517  * @xent: non-zero if the directory entry is an extended attribute entry
 518  *
 519  * This function updates an inode by writing a directory entry (or extended
 520  * attribute entry), the inode itself, and the parent directory inode (or the
 521  * host inode) to the journal.
 522  *
 523  * The function writes the host inode @dir last, which is important in case of
 524  * extended attributes. Indeed, then we guarantee that if the host inode gets
 525  * synchronized (with 'fsync()'), and the write-buffer it sits in gets flushed,
 526  * the extended attribute inode gets flushed too. And this is exactly what the
 527  * user expects - synchronizing the host inode synchronizes its extended
 528  * attributes. Similarly, this guarantees that if @dir is synchronized, its
 529  * directory entry corresponding to @nm gets synchronized too.
 530  *
 531  * If the inode (@inode) or the parent directory (@dir) are synchronous, this
 532  * function synchronizes the write-buffer.
 533  *
 534  * This function marks the @dir and @inode inodes as clean and returns zero on
 535  * success. In case of failure, a negative error code is returned.
 536  */
 537 int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
 538                      const struct qstr *nm, const struct inode *inode,
 539                      int deletion, int xent)
 540 {
 541         int err, dlen, ilen, len, lnum, ino_offs, dent_offs;
 542         int aligned_dlen, aligned_ilen, sync = IS_DIRSYNC(dir);
 543         int last_reference = !!(deletion && inode->i_nlink == 0);
 544         struct ubifs_inode *ui = ubifs_inode(inode);
 545         struct ubifs_inode *dir_ui = ubifs_inode(dir);
 546         struct ubifs_dent_node *dent;
 547         struct ubifs_ino_node *ino;
 548         union ubifs_key dent_key, ino_key;
 549
 550         dbg_jnl("ino %lu, dent '%.*s', data len %d in dir ino %lu",
 551                 inode->i_ino, nm->len, nm->name, ui->data_len, dir->i_ino);
 552         ubifs_assert(dir_ui->data_len == 0);
 553         ubifs_assert(mutex_is_locked(&dir_ui->ui_mutex));
 554
 555         dlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
 556         ilen = UBIFS_INO_NODE_SZ;
 557
 558         /*
 559          * If the last reference to the inode is being deleted, then there is
 560          * no need to attach and write inode data, it is being deleted anyway.
 561          * And if the inode is being deleted, no need to synchronize
 562          * write-buffer even if the inode is synchronous.
 563          */
 564         if (!last_reference) {
 565                 ilen += ui->data_len;
 566                 sync |= IS_SYNC(inode);
 567         }
 568
 569         aligned_dlen = ALIGN(dlen, 8);
 570         aligned_ilen = ALIGN(ilen, 8);
 571         len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ;
 572         dent = kmalloc(len, GFP_NOFS);
 573         if (!dent)
 574                 return -ENOMEM;
 575
 576         /* Make reservation before allocating sequence numbers */
 577         err = make_reservation(c, BASEHD, len);
 578         if (err)
 579                 goto out_free;
 580
 581         if (!xent) {
 582                 dent->ch.node_type = UBIFS_DENT_NODE;
 583                 dent_key_init(c, &dent_key, dir->i_ino, nm);
 584         } else {
 585                 dent->ch.node_type = UBIFS_XENT_NODE;
 586                 xent_key_init(c, &dent_key, dir->i_ino, nm);
 587         }
 588
 589         key_write(c, &dent_key, dent->key);
 590         dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino);
 591         dent->type = get_dent_type(inode->i_mode);
 592         dent->nlen = cpu_to_le16(nm->len);
 593         memcpy(dent->name, nm->name, nm->len);
 594         dent->name[nm->len] = '\0';
 595         zero_dent_node_unused(dent);
 596         ubifs_prep_grp_node(c, dent, dlen, 0);
 597
 598         ino = (void *)dent + aligned_dlen;
 599         pack_inode(c, ino, inode, 0, last_reference);
 600         ino = (void *)ino + aligned_ilen;
 601         pack_inode(c, ino, dir, 1, 0);
 602
 603         if (last_reference) {
 604                 err = ubifs_add_orphan(c, inode->i_ino);
 605                 if (err) {
 606                         release_head(c, BASEHD);
 607                         goto out_finish;
 608                 }
 609         }
 610
 611         err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
 612         if (err)
 613                 goto out_release;
 614         if (!sync) {
 615                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
 616
 617                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
 618                 ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
 619         }
 620         release_head(c, BASEHD);
 621         kfree(dent);
 622
 623         if (deletion) {
 624                 err = ubifs_tnc_remove_nm(c, &dent_key, nm);
 625                 if (err)
 626                         goto out_ro;
 627                 err = ubifs_add_dirt(c, lnum, dlen);
 628         } else
 629                 err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm);
 630         if (err)
 631                 goto out_ro;
 632
 633         /*
 634          * Note, we do not remove the inode from TNC even if the last reference
 635          * to it has just been deleted, because the inode may still be opened.
 636          * Instead, the inode has been added to orphan lists and the orphan
 637          * subsystem will take further care about it.
 638          */
 639         ino_key_init(c, &ino_key, inode->i_ino);
 640         ino_offs = dent_offs + aligned_dlen;
 641         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
 642         if (err)
 643                 goto out_ro;
 644
 645         ino_key_init(c, &ino_key, dir->i_ino);
 646         ino_offs += aligned_ilen;
 647         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ);
 648         if (err)
 649                 goto out_ro;
 650
 651         finish_reservation(c);
 652         spin_lock(&ui->ui_lock);
 653         ui->synced_i_size = ui->ui_size;
 654         spin_unlock(&ui->ui_lock);
 655         mark_inode_clean(c, ui);
 656         mark_inode_clean(c, dir_ui);
 657         return 0;
 658
 659 out_finish:
 660         finish_reservation(c);
 661 out_free:
 662         kfree(dent);
 663         return err;
 664
 665 out_release:
 666         release_head(c, BASEHD);
 667 out_ro:
 668         ubifs_ro_mode(c, err);
 669         if (last_reference)
 670                 ubifs_delete_orphan(c, inode->i_ino);
 671         finish_reservation(c);
 672         return err;
 673 }
 674
 675 /**
 676  * ubifs_jnl_write_data - write a data node to the journal.
 677  * @c: UBIFS file-system description object
 678  * @inode: inode the data node belongs to
 679  * @key: node key
 680  * @buf: buffer to write
 681  * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
 682  *
 683  * This function writes a data node to the journal. Returns %0 if the data node
 684  * was successfully written, and a negative error code in case of failure.
 685  */
 686 int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
 687                          const union ubifs_key *key, const void *buf, int len)
 688 {
 689         struct ubifs_data_node *data;
 690         int err, lnum, offs, compr_type, out_len;
 691         int dlen = UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR;
 692         struct ubifs_inode *ui = ubifs_inode(inode);
 693
 694         dbg_jnl("ino %lu, blk %u, len %d, key %s", key_inum(c, key),
 695                 key_block(c, key), len, DBGKEY(key));
 696         ubifs_assert(len <= UBIFS_BLOCK_SIZE);
 697
 698         data = kmalloc(dlen, GFP_NOFS);
 699         if (!data)
 700                 return -ENOMEM;
 701
 702         data->ch.node_type = UBIFS_DATA_NODE;
 703         key_write(c, key, &data->key);
 704         data->size = cpu_to_le32(len);
 705         zero_data_node_unused(data);
 706
 707         if (!(ui->flags && UBIFS_COMPR_FL))
 708                 /* Compression is disabled for this inode */
 709                 compr_type = UBIFS_COMPR_NONE;
 710         else
 711                 compr_type = ui->compr_type;
 712
 713         out_len = dlen - UBIFS_DATA_NODE_SZ;
 714         ubifs_compress(buf, len, &data->data, &out_len, &compr_type);
 715         ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
 716
 717         dlen = UBIFS_DATA_NODE_SZ + out_len;
 718         data->compr_type = cpu_to_le16(compr_type);
 719
 720         /* Make reservation before allocating sequence numbers */
 721         err = make_reservation(c, DATAHD, dlen);
 722         if (err)
 723                 goto out_free;
 724
 725         err = write_node(c, DATAHD, data, dlen, &lnum, &offs);
 726         if (err)
 727                 goto out_release;
 728         ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
 729         release_head(c, DATAHD);
 730
 731         err = ubifs_tnc_add(c, key, lnum, offs, dlen);
 732         if (err)
 733                 goto out_ro;
 734
 735         finish_reservation(c);
 736         kfree(data);
 737         return 0;
 738
 739 out_release:
 740         release_head(c, DATAHD);
 741 out_ro:
 742         ubifs_ro_mode(c, err);
 743         finish_reservation(c);
 744 out_free:
 745         kfree(data);
 746         return err;
 747 }
 748
 749 /**
 750  * ubifs_jnl_write_inode - flush inode to the journal.
 751  * @c: UBIFS file-system description object
 752  * @inode: inode to flush
 753  * @deletion: inode has been deleted
 754  *
 755  * This function writes inode @inode to the journal. If the inode is
 756  * synchronous, it also synchronizes the write-buffer. Returns zero in case of
 757  * success and a negative error code in case of failure.
 758  */
 759 int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode,
 760                           int deletion)
 761 {
 762         int err, len, lnum, offs, sync = 0;
 763         struct ubifs_ino_node *ino;
 764         struct ubifs_inode *ui = ubifs_inode(inode);
 765
 766         dbg_jnl("ino %lu%s", inode->i_ino,
 767                 deletion ? " (last reference)" : "");
 768         if (deletion)
 769                 ubifs_assert(inode->i_nlink == 0);
 770
 771         len = UBIFS_INO_NODE_SZ;
 772         /*
 773          * If the inode is being deleted, do not write the attached data. No
 774          * need to synchronize the write-buffer either.
 775          */
 776         if (!deletion) {
 777                 len += ui->data_len;
 778                 sync = IS_SYNC(inode);
 779         }
 780         ino = kmalloc(len, GFP_NOFS);
 781         if (!ino)
 782                 return -ENOMEM;
 783
 784         /* Make reservation before allocating sequence numbers */
 785         err = make_reservation(c, BASEHD, len);
 786         if (err)
 787                 goto out_free;
 788
 789         pack_inode(c, ino, inode, 1, deletion);
 790         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
 791         if (err)
 792                 goto out_release;
 793         if (!sync)
 794                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
 795                                           inode->i_ino);
 796         release_head(c, BASEHD);
 797
 798         if (deletion) {
 799                 err = ubifs_tnc_remove_ino(c, inode->i_ino);
 800                 if (err)
 801                         goto out_ro;
 802                 ubifs_delete_orphan(c, inode->i_ino);
 803                 err = ubifs_add_dirt(c, lnum, len);
 804         } else {
 805                 union ubifs_key key;
 806
 807                 ino_key_init(c, &key, inode->i_ino);
 808                 err = ubifs_tnc_add(c, &key, lnum, offs, len);
 809         }
 810         if (err)
 811                 goto out_ro;
 812
 813         finish_reservation(c);
 814         spin_lock(&ui->ui_lock);
 815         ui->synced_i_size = ui->ui_size;
 816         spin_unlock(&ui->ui_lock);
 817         kfree(ino);
 818         return 0;
 819
 820 out_release:
 821         release_head(c, BASEHD);
 822 out_ro:
 823         ubifs_ro_mode(c, err);
 824         finish_reservation(c);
 825 out_free:
 826         kfree(ino);
 827         return err;
 828 }
 829
 830 /**
 831  * ubifs_jnl_rename - rename a directory entry.
 832  * @c: UBIFS file-system description object
 833  * @old_dir: parent inode of directory entry to rename
 834  * @old_dentry: directory entry to rename
 835  * @new_dir: parent inode of directory entry to rename
 836  * @new_dentry: new directory entry (or directory entry to replace)
 837  * @sync: non-zero if the write-buffer has to be synchronized
 838  *
 839  * This function implements the re-name operation which may involve writing up
 840  * to 3 inodes and 2 directory entries. It marks the written inodes as clean
 841  * and returns zero on success. In case of failure, a negative error code is
 842  * returned.
 843  */
 844 int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
 845                      const struct dentry *old_dentry,
 846                      const struct inode *new_dir,
 847                      const struct dentry *new_dentry, int sync)
 848 {
 849         void *p;
 850         union ubifs_key key;
 851         struct ubifs_dent_node *dent, *dent2;
 852         int err, dlen1, dlen2, ilen, lnum, offs, len;
 853         const struct inode *old_inode = old_dentry->d_inode;
 854         const struct inode *new_inode = new_dentry->d_inode;
 855         int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
 856         int last_reference = !!(new_inode && new_inode->i_nlink == 0);
 857         int move = (old_dir != new_dir);
 858         struct ubifs_inode *uninitialized_var(new_ui);
 859
 860         dbg_jnl("dent '%.*s' in dir ino %lu to dent '%.*s' in dir ino %lu",
 861                 old_dentry->d_name.len, old_dentry->d_name.name,
 862                 old_dir->i_ino, new_dentry->d_name.len,
 863                 new_dentry->d_name.name, new_dir->i_ino);
 864         ubifs_assert(ubifs_inode(old_dir)->data_len == 0);
 865         ubifs_assert(ubifs_inode(new_dir)->data_len == 0);
 866         ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
 867         ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
 868
 869         dlen1 = UBIFS_DENT_NODE_SZ + new_dentry->d_name.len + 1;
 870         dlen2 = UBIFS_DENT_NODE_SZ + old_dentry->d_name.len + 1;
 871         if (new_inode) {
 872                 new_ui = ubifs_inode(new_inode);
 873                 ubifs_assert(mutex_is_locked(&new_ui->ui_mutex));
 874                 ilen = UBIFS_INO_NODE_SZ;
 875                 if (!last_reference)
 876                         ilen += new_ui->data_len;
 877         } else
 878                 ilen = 0;
 879
 880         aligned_dlen1 = ALIGN(dlen1, 8);
 881         aligned_dlen2 = ALIGN(dlen2, 8);
 882         len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8);
 883         if (old_dir != new_dir)
 884                 len += plen;
 885         dent = kmalloc(len, GFP_NOFS);
 886         if (!dent)
 887                 return -ENOMEM;
 888
 889         /* Make reservation before allocating sequence numbers */
 890         err = make_reservation(c, BASEHD, len);
 891         if (err)
 892                 goto out_free;
 893
 894         /* Make new dent */
 895         dent->ch.node_type = UBIFS_DENT_NODE;
 896         dent_key_init_flash(c, &dent->key, new_dir->i_ino, &new_dentry->d_name);
 897         dent->inum = cpu_to_le64(old_inode->i_ino);
 898         dent->type = get_dent_type(old_inode->i_mode);
 899         dent->nlen = cpu_to_le16(new_dentry->d_name.len);
 900         memcpy(dent->name, new_dentry->d_name.name, new_dentry->d_name.len);
 901         dent->name[new_dentry->d_name.len] = '\0';
 902         zero_dent_node_unused(dent);
 903         ubifs_prep_grp_node(c, dent, dlen1, 0);
 904
 905         /* Make deletion dent */
 906         dent2 = (void *)dent + aligned_dlen1;
 907         dent2->ch.node_type = UBIFS_DENT_NODE;
 908         dent_key_init_flash(c, &dent2->key, old_dir->i_ino,
 909                             &old_dentry->d_name);
 910         dent2->inum = 0;
 911         dent2->type = DT_UNKNOWN;
 912         dent2->nlen = cpu_to_le16(old_dentry->d_name.len);
 913         memcpy(dent2->name, old_dentry->d_name.name, old_dentry->d_name.len);
 914         dent2->name[old_dentry->d_name.len] = '\0';
 915         zero_dent_node_unused(dent2);
 916         ubifs_prep_grp_node(c, dent2, dlen2, 0);
 917
 918         p = (void *)dent2 + aligned_dlen2;
 919         if (new_inode) {
 920                 pack_inode(c, p, new_inode, 0, last_reference);
 921                 p += ALIGN(ilen, 8);
 922         }
 923
 924         if (!move)
 925                 pack_inode(c, p, old_dir, 1, 0);
 926         else {
 927                 pack_inode(c, p, old_dir, 0, 0);
 928                 p += ALIGN(plen, 8);
 929                 pack_inode(c, p, new_dir, 1, 0);
 930         }
 931
 932         if (last_reference) {
 933                 err = ubifs_add_orphan(c, new_inode->i_ino);
 934                 if (err) {
 935                         release_head(c, BASEHD);
 936                         goto out_finish;
 937                 }
 938         }
 939
 940         err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
 941         if (err)
 942                 goto out_release;
 943         if (!sync) {
 944                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
 945
 946                 ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
 947                 ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
 948                 if (new_inode)
 949                         ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
 950                                                   new_inode->i_ino);
 951         }
 952         release_head(c, BASEHD);
 953
 954         dent_key_init(c, &key, new_dir->i_ino, &new_dentry->d_name);
 955         err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &new_dentry->d_name);
 956         if (err)
 957                 goto out_ro;
 958
 959         err = ubifs_add_dirt(c, lnum, dlen2);
 960         if (err)
 961                 goto out_ro;
 962
 963         dent_key_init(c, &key, old_dir->i_ino, &old_dentry->d_name);
 964         err = ubifs_tnc_remove_nm(c, &key, &old_dentry->d_name);
 965         if (err)
 966                 goto out_ro;
 967
 968         offs += aligned_dlen1 + aligned_dlen2;
 969         if (new_inode) {
 970                 ino_key_init(c, &key, new_inode->i_ino);
 971                 err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
 972                 if (err)
 973                         goto out_ro;
 974                 offs += ALIGN(ilen, 8);
 975         }
 976
 977         ino_key_init(c, &key, old_dir->i_ino);
 978         err = ubifs_tnc_add(c, &key, lnum, offs, plen);
 979         if (err)
 980                 goto out_ro;
 981
 982         if (old_dir != new_dir) {
 983                 offs += ALIGN(plen, 8);
 984                 ino_key_init(c, &key, new_dir->i_ino);
 985                 err = ubifs_tnc_add(c, &key, lnum, offs, plen);
 986                 if (err)
 987                         goto out_ro;
 988         }
 989
 990         finish_reservation(c);
 991         if (new_inode) {
 992                 mark_inode_clean(c, new_ui);
 993                 spin_lock(&new_ui->ui_lock);
 994                 new_ui->synced_i_size = new_ui->ui_size;
 995                 spin_unlock(&new_ui->ui_lock);
 996         }
 997         mark_inode_clean(c, ubifs_inode(old_dir));
 998         if (move)
 999                 mark_inode_clean(c, ubifs_inode(new_dir));
1000         kfree(dent);
1001         return 0;
1002
1003 out_release:
1004         release_head(c, BASEHD);
1005 out_ro:
1006         ubifs_ro_mode(c, err);
1007         if (last_reference)
1008                 ubifs_delete_orphan(c, new_inode->i_ino);
1009 out_finish:
1010         finish_reservation(c);
1011 out_free:
1012         kfree(dent);
1013         return err;
1014 }
1015
1016 /**
1017  * recomp_data_node - re-compress a truncated data node.
1018  * @dn: data node to re-compress
1019  * @new_len: new length
1020  *
1021  * This function is used when an inode is truncated and the last data node of
1022  * the inode has to be re-compressed and re-written.
1023  */
1024 static int recomp_data_node(struct ubifs_data_node *dn, int *new_len)
1025 {
1026         void *buf;
1027         int err, len, compr_type, out_len;
1028
1029         out_len = le32_to_cpu(dn->size);
1030         buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
1031         if (!buf)
1032                 return -ENOMEM;
1033
1034         len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
1035         compr_type = le16_to_cpu(dn->compr_type);
1036         err = ubifs_decompress(&dn->data, len, buf, &out_len, compr_type);
1037         if (err)
1038                 goto out;
1039
1040         ubifs_compress(buf, *new_len, &dn->data, &out_len, &compr_type);
1041         ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
1042         dn->compr_type = cpu_to_le16(compr_type);
1043         dn->size = cpu_to_le32(*new_len);
1044         *new_len = UBIFS_DATA_NODE_SZ + out_len;
1045 out:
1046         kfree(buf);
1047         return err;
1048 }
1049
1050 /**
1051  * ubifs_jnl_truncate - update the journal for a truncation.
1052  * @c: UBIFS file-system description object
1053  * @inode: inode to truncate
1054  * @old_size: old size
1055  * @new_size: new size
1056  *
1057  * When the size of a file decreases due to truncation, a truncation node is
1058  * written, the journal tree is updated, and the last data block is re-written
1059  * if it has been affected. The inode is also updated in order to synchronize
1060  * the new inode size.
1061  *
1062  * This function marks the inode as clean and returns zero on success. In case
1063  * of failure, a negative error code is returned.
1064  */
1065 int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1066                        loff_t old_size, loff_t new_size)
1067 {
1068         union ubifs_key key, to_key;
1069         struct ubifs_ino_node *ino;
1070         struct ubifs_trun_node *trun;
1071         struct ubifs_data_node *uninitialized_var(dn);
1072         int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
1073         struct ubifs_inode *ui = ubifs_inode(inode);
1074         ino_t inum = inode->i_ino;
1075         unsigned int blk;
1076
1077         dbg_jnl("ino %lu, size %lld -> %lld", inum, old_size, new_size);
1078         ubifs_assert(!ui->data_len);
1079         ubifs_assert(S_ISREG(inode->i_mode));
1080         ubifs_assert(mutex_is_locked(&ui->ui_mutex));
1081
1082         sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
1083              UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
1084         ino = kmalloc(sz, GFP_NOFS);
1085         if (!ino)
1086                 return -ENOMEM;
1087
1088         trun = (void *)ino + UBIFS_INO_NODE_SZ;
1089         trun->ch.node_type = UBIFS_TRUN_NODE;
1090         trun->inum = cpu_to_le32(inum);
1091         trun->old_size = cpu_to_le64(old_size);
1092         trun->new_size = cpu_to_le64(new_size);
1093         zero_trun_node_unused(trun);
1094
1095         dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
1096         if (dlen) {
1097                 /* Get last data block so it can be truncated */
1098                 dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
1099                 blk = new_size >> UBIFS_BLOCK_SHIFT;
1100                 data_key_init(c, &key, inum, blk);
1101                 dbg_jnl("last block key %s", DBGKEY(&key));
1102                 err = ubifs_tnc_lookup(c, &key, dn);
1103                 if (err == -ENOENT)
1104                         dlen = 0; /* Not found (so it is a hole) */
1105                 else if (err)
1106                         goto out_free;
1107                 else {
1108                         if (le32_to_cpu(dn->size) <= dlen)
1109                                 dlen = 0; /* Nothing to do */
1110                         else {
1111                                 int compr_type = le16_to_cpu(dn->compr_type);
1112
1113                                 if (compr_type != UBIFS_COMPR_NONE) {
1114                                         err = recomp_data_node(dn, &dlen);
1115                                         if (err)
1116                                                 goto out_free;
1117                                 } else {
1118                                         dn->size = cpu_to_le32(dlen);
1119                                         dlen += UBIFS_DATA_NODE_SZ;
1120                                 }
1121                                 zero_data_node_unused(dn);
1122                         }
1123                 }
1124         }
1125
1126         /* Must make reservation before allocating sequence numbers */
1127         len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
1128         if (dlen)
1129                 len += dlen;
1130         err = make_reservation(c, BASEHD, len);
1131         if (err)
1132                 goto out_free;
1133
1134         pack_inode(c, ino, inode, 0, 0);
1135         ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
1136         if (dlen)
1137                 ubifs_prep_grp_node(c, dn, dlen, 1);
1138
1139         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
1140         if (err)
1141                 goto out_release;
1142         if (!sync)
1143                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
1144         release_head(c, BASEHD);
1145
1146         if (dlen) {
1147                 sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
1148                 err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
1149                 if (err)
1150                         goto out_ro;
1151         }
1152
1153         ino_key_init(c, &key, inum);
1154         err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
1155         if (err)
1156                 goto out_ro;
1157
1158         err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
1159         if (err)
1160                 goto out_ro;
1161
1162         bit = new_size & (UBIFS_BLOCK_SIZE - 1);
1163         blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
1164         data_key_init(c, &key, inum, blk);
1165
1166         bit = old_size & (UBIFS_BLOCK_SIZE - 1);
1167         blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0: 1);
1168         data_key_init(c, &to_key, inum, blk);
1169
1170         err = ubifs_tnc_remove_range(c, &key, &to_key);
1171         if (err)
1172                 goto out_ro;
1173
1174         finish_reservation(c);
1175         spin_lock(&ui->ui_lock);
1176         ui->synced_i_size = ui->ui_size;
1177         spin_unlock(&ui->ui_lock);
1178         mark_inode_clean(c, ui);
1179         kfree(ino);
1180         return 0;
1181
1182 out_release:
1183         release_head(c, BASEHD);
1184 out_ro:
1185         ubifs_ro_mode(c, err);
1186         finish_reservation(c);
1187 out_free:
1188         kfree(ino);
1189         return err;
1190 }
1191
1192 #ifdef CONFIG_UBIFS_FS_XATTR
1193
1194 /**
1195  * ubifs_jnl_delete_xattr - delete an extended attribute.
1196  * @c: UBIFS file-system description object
1197  * @host: host inode
1198  * @inode: extended attribute inode
1199  * @nm: extended attribute entry name
1200  *
1201  * This function delete an extended attribute which is very similar to
1202  * un-linking regular files - it writes a deletion xentry, a deletion inode and
1203  * updates the target inode. Returns zero in case of success and a negative
1204  * error code in case of failure.
1205  */
1206 int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1207                            const struct inode *inode, const struct qstr *nm)
1208 {
1209         int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
1210         struct ubifs_dent_node *xent;
1211         struct ubifs_ino_node *ino;
1212         union ubifs_key xent_key, key1, key2;
1213         int sync = IS_DIRSYNC(host);
1214         struct ubifs_inode *host_ui = ubifs_inode(host);
1215
1216         dbg_jnl("host %lu, xattr ino %lu, name '%s', data len %d",
1217                 host->i_ino, inode->i_ino, nm->name,
1218                 ubifs_inode(inode)->data_len);
1219         ubifs_assert(inode->i_nlink == 0);
1220         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1221
1222         /*
1223          * Since we are deleting the inode, we do not bother to attach any data
1224          * to it and assume its length is %UBIFS_INO_NODE_SZ.
1225          */
1226         xlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
1227         aligned_xlen = ALIGN(xlen, 8);
1228         hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
1229         len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
1230
1231         xent = kmalloc(len, GFP_NOFS);
1232         if (!xent)
1233                 return -ENOMEM;
1234
1235         /* Make reservation before allocating sequence numbers */
1236         err = make_reservation(c, BASEHD, len);
1237         if (err) {
1238                 kfree(xent);
1239                 return err;
1240         }
1241
1242         xent->ch.node_type = UBIFS_XENT_NODE;
1243         xent_key_init(c, &xent_key, host->i_ino, nm);
1244         key_write(c, &xent_key, xent->key);
1245         xent->inum = 0;
1246         xent->type = get_dent_type(inode->i_mode);
1247         xent->nlen = cpu_to_le16(nm->len);
1248         memcpy(xent->name, nm->name, nm->len);
1249         xent->name[nm->len] = '\0';
1250         zero_dent_node_unused(xent);
1251         ubifs_prep_grp_node(c, xent, xlen, 0);
1252
1253         ino = (void *)xent + aligned_xlen;
1254         pack_inode(c, ino, inode, 0, 1);
1255         ino = (void *)ino + UBIFS_INO_NODE_SZ;
1256         pack_inode(c, ino, host, 1, 0);
1257
1258         err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
1259         if (!sync && !err)
1260                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
1261         release_head(c, BASEHD);
1262         kfree(xent);
1263         if (err)
1264                 goto out_ro;
1265
1266         /* Remove the extended attribute entry from TNC */
1267         err = ubifs_tnc_remove_nm(c, &xent_key, nm);
1268         if (err)
1269                 goto out_ro;
1270         err = ubifs_add_dirt(c, lnum, xlen);
1271         if (err)
1272                 goto out_ro;
1273
1274         /*
1275          * Remove all nodes belonging to the extended attribute inode from TNC.
1276          * Well, there actually must be only one node - the inode itself.
1277          */
1278         lowest_ino_key(c, &key1, inode->i_ino);
1279         highest_ino_key(c, &key2, inode->i_ino);
1280         err = ubifs_tnc_remove_range(c, &key1, &key2);
1281         if (err)
1282                 goto out_ro;
1283         err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
1284         if (err)
1285                 goto out_ro;
1286
1287         /* And update TNC with the new host inode position */
1288         ino_key_init(c, &key1, host->i_ino);
1289         err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
1290         if (err)
1291                 goto out_ro;
1292
1293         finish_reservation(c);
1294         spin_lock(&host_ui->ui_lock);
1295         host_ui->synced_i_size = host_ui->ui_size;
1296         spin_unlock(&host_ui->ui_lock);
1297         mark_inode_clean(c, host_ui);
1298         return 0;
1299
1300 out_ro:
1301         ubifs_ro_mode(c, err);
1302         finish_reservation(c);
1303         return err;
1304 }
1305
1306 /**
1307  * ubifs_jnl_change_xattr - change an extended attribute.
1308  * @c: UBIFS file-system description object
1309  * @inode: extended attribute inode
1310  * @host: host inode
1311  *
1312  * This function writes the updated version of an extended attribute inode and
1313  * the host inode tho the journal (to the base head). The host inode is written
1314  * after the extended attribute inode in order to guarantee that the extended
1315  * attribute will be flushed when the inode is synchronized by 'fsync()' and
1316  * consequently, the write-buffer is synchronized. This function returns zero
1317  * in case of success and a negative error code in case of failure.
1318  */
1319 int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
1320                            const struct inode *host)
1321 {
1322         int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
1323         struct ubifs_inode *host_ui = ubifs_inode(inode);
1324         struct ubifs_ino_node *ino;
1325         union ubifs_key key;
1326         int sync = IS_DIRSYNC(host);
1327
1328         dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
1329         ubifs_assert(host->i_nlink > 0);
1330         ubifs_assert(inode->i_nlink > 0);
1331         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1332
1333         len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
1334         len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
1335         aligned_len1 = ALIGN(len1, 8);
1336         aligned_len = aligned_len1 + ALIGN(len2, 8);
1337
1338         ino = kmalloc(aligned_len, GFP_NOFS);
1339         if (!ino)
1340                 return -ENOMEM;
1341
1342         /* Make reservation before allocating sequence numbers */
1343         err = make_reservation(c, BASEHD, aligned_len);
1344         if (err)
1345                 goto out_free;
1346
1347         pack_inode(c, ino, host, 0, 0);
1348         pack_inode(c, (void *)ino + aligned_len1, inode, 1, 0);
1349
1350         err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
1351         if (!sync && !err) {
1352                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1353
1354                 ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
1355                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
1356         }
1357         release_head(c, BASEHD);
1358         if (err)
1359                 goto out_ro;
1360
1361         ino_key_init(c, &key, host->i_ino);
1362         err = ubifs_tnc_add(c, &key, lnum, offs, len1);
1363         if (err)
1364                 goto out_ro;
1365
1366         ino_key_init(c, &key, inode->i_ino);
1367         err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
1368         if (err)
1369                 goto out_ro;
1370
1371         finish_reservation(c);
1372         spin_lock(&host_ui->ui_lock);
1373         host_ui->synced_i_size = host_ui->ui_size;
1374         spin_unlock(&host_ui->ui_lock);
1375         mark_inode_clean(c, host_ui);
1376         kfree(ino);
1377         return 0;
1378
1379 out_ro:
1380         ubifs_ro_mode(c, err);
1381         finish_reservation(c);
1382 out_free:
1383         kfree(ino);
1384         return err;
1385 }
1386
1387 #endif /* CONFIG_UBIFS_FS_XATTR */