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, 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, &offs, squeeze);
 143         if (lnum >= 0) {
 144                 /* Found an LEB, add it to the journal head */
 145                 err = ubifs_add_bud_to_log(c, jhead, lnum, offs);
 146                 if (err)
 147                         goto out_return;
 148                 /* A new bud was successfully allocated and added to the log */
 149                 goto out;
 150         }
 151
 152         err = lnum;
 153         if (err != -ENOSPC)
 154                 goto out_unlock;
 155
 156         /*
 157          * No free space, we have to run garbage collector to make
 158          * some. But the write-buffer mutex has to be unlocked because
 159          * GC also takes it.
 160          */
 161         dbg_jnl("no free space in jhead %s, run GC", dbg_jhead(jhead));
 162         mutex_unlock(&wbuf->io_mutex);
 163
 164         lnum = ubifs_garbage_collect(c, 0);
 165         if (lnum < 0) {
 166                 err = lnum;
 167                 if (err != -ENOSPC)
 168                         return err;
 169
 170                 /*
 171                  * GC could not make a free LEB. But someone else may
 172                  * have allocated new bud for this journal head,
 173                  * because we dropped @wbuf->io_mutex, so try once
 174                  * again.
 175                  */
 176                 dbg_jnl("GC couldn't make a free LEB for jhead %s",
 177                         dbg_jhead(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 %s", lnum, dbg_jhead(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 than 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, wbuf->dtype);
 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 %s, LEB %d:%d, len %d",
 260                 dbg_jhead(jhead), *lnum, *offs, len);
 261         ubifs_prepare_node(c, node, len, 0);
 262
 263         return ubifs_wbuf_write_nolock(wbuf, node, len);
 264 }
 265
 266 /**
 267  * write_head - write data to a journal head.
 268  * @c: UBIFS file-system description object
 269  * @jhead: journal head
 270  * @buf: buffer to write
 271  * @len: length to write
 272  * @lnum: LEB number written is returned here
 273  * @offs: offset written is returned here
 274  * @sync: non-zero if the write-buffer has to by synchronized
 275  *
 276  * This function is the same as 'write_node()' but it does not assume the
 277  * buffer it is writing is a node, so it does not prepare it (which means
 278  * initializing common header and calculating CRC).
 279  */
 280 static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
 281                       int *lnum, int *offs, int sync)
 282 {
 283         int err;
 284         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 285
 286         ubifs_assert(jhead != GCHD);
 287
 288         *lnum = c->jheads[jhead].wbuf.lnum;
 289         *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 290         dbg_jnl("jhead %s, LEB %d:%d, len %d",
 291                 dbg_jhead(jhead), *lnum, *offs, len);
 292
 293         err = ubifs_wbuf_write_nolock(wbuf, buf, len);
 294         if (err)
 295                 return err;
 296         if (sync)
 297                 err = ubifs_wbuf_sync_nolock(wbuf);
 298         return err;
 299 }
 300
 301 /**
 302  * make_reservation - reserve journal space.
 303  * @c: UBIFS file-system description object
 304  * @jhead: journal head
 305  * @len: how many bytes to reserve
 306  *
 307  * This function makes space reservation in journal head @jhead. The function
 308  * takes the commit lock and locks the journal head, and the caller has to
 309  * unlock the head and finish the reservation with 'finish_reservation()'.
 310  * Returns zero in case of success and a negative error code in case of
 311  * failure.
 312  *
 313  * Note, the journal head may be unlocked as soon as the data is written, while
 314  * the commit lock has to be released after the data has been added to the
 315  * TNC.
 316  */
 317 static int make_reservation(struct ubifs_info *c, int jhead, int len)
 318 {
 319         int err, cmt_retries = 0, nospc_retries = 0;
 320
 321 again:
 322         down_read(&c->commit_sem);
 323         err = reserve_space(c, jhead, len);
 324         if (!err)
 325                 return 0;
 326         up_read(&c->commit_sem);
 327
 328         if (err == -ENOSPC) {
 329                 /*
 330                  * GC could not make any progress. We should try to commit
 331                  * once because it could make some dirty space and GC would
 332                  * make progress, so make the error -EAGAIN so that the below
 333                  * will commit and re-try.
 334                  */
 335                 if (nospc_retries++ < 2) {
 336                         dbg_jnl("no space, retry");
 337                         err = -EAGAIN;
 338                 }
 339
 340                 /*
 341                  * This means that the budgeting is incorrect. We always have
 342                  * to be able to write to the media, because all operations are
 343                  * budgeted. Deletions are not budgeted, though, but we reserve
 344                  * an extra LEB for them.
 345                  */
 346         }
 347
 348         if (err != -EAGAIN)
 349                 goto out;
 350
 351         /*
 352          * -EAGAIN means that the journal is full or too large, or the above
 353          * code wants to do one commit. Do this and re-try.
 354          */
 355         if (cmt_retries > 128) {
 356                 /*
 357                  * This should not happen unless the journal size limitations
 358                  * are too tough.
 359                  */
 360                 ubifs_err("stuck in space allocation");
 361                 err = -ENOSPC;
 362                 goto out;
 363         } else if (cmt_retries > 32)
 364                 ubifs_warn("too many space allocation re-tries (%d)",
 365                            cmt_retries);
 366
 367         dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
 368                 cmt_retries);
 369         cmt_retries += 1;
 370
 371         err = ubifs_run_commit(c);
 372         if (err)
 373                 return err;
 374         goto again;
 375
 376 out:
 377         ubifs_err("cannot reserve %d bytes in jhead %d, error %d",
 378                   len, jhead, err);
 379         if (err == -ENOSPC) {
 380                 /* This are some budgeting problems, print useful information */
 381                 down_write(&c->commit_sem);
 382                 spin_lock(&c->space_lock);
 383                 dbg_dump_stack();
 384                 dbg_dump_budg(c);
 385                 spin_unlock(&c->space_lock);
 386                 dbg_dump_lprops(c);
 387                 cmt_retries = dbg_check_lprops(c);
 388                 up_write(&c->commit_sem);
 389         }
 390         return err;
 391 }
 392
 393 /**
 394  * release_head - release a journal head.
 395  * @c: UBIFS file-system description object
 396  * @jhead: journal head
 397  *
 398  * This function releases journal head @jhead which was locked by
 399  * the 'make_reservation()' function. It has to be called after each successful
 400  * 'make_reservation()' invocation.
 401  */
 402 static inline void release_head(struct ubifs_info *c, int jhead)
 403 {
 404         mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
 405 }
 406
 407 /**
 408  * finish_reservation - finish a reservation.
 409  * @c: UBIFS file-system description object
 410  *
 411  * This function finishes journal space reservation. It must be called after
 412  * 'make_reservation()'.
 413  */
 414 static void finish_reservation(struct ubifs_info *c)
 415 {
 416         up_read(&c->commit_sem);
 417 }
 418
 419 /**
 420  * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
 421  * @mode: inode mode
 422  */
 423 static int get_dent_type(int mode)
 424 {
 425         switch (mode & S_IFMT) {
 426         case S_IFREG:
 427                 return UBIFS_ITYPE_REG;
 428         case S_IFDIR:
 429                 return UBIFS_ITYPE_DIR;
 430         case S_IFLNK:
 431                 return UBIFS_ITYPE_LNK;
 432         case S_IFBLK:
 433                 return UBIFS_ITYPE_BLK;
 434         case S_IFCHR:
 435                 return UBIFS_ITYPE_CHR;
 436         case S_IFIFO:
 437                 return UBIFS_ITYPE_FIFO;
 438         case S_IFSOCK:
 439                 return UBIFS_ITYPE_SOCK;
 440         default:
 441                 BUG();
 442         }
 443         return 0;
 444 }
 445
 446 /**
 447  * pack_inode - pack an inode node.
 448  * @c: UBIFS file-system description object
 449  * @ino: buffer in which to pack inode node
 450  * @inode: inode to pack
 451  * @last: indicates the last node of the group
 452  */
 453 static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
 454                        const struct inode *inode, int last)
 455 {
 456         int data_len = 0, last_reference = !inode->i_nlink;
 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);
 600         ino = (void *)ino + aligned_ilen;
 601         pack_inode(c, ino, dir, 1);
 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                 ui->del_cmtno = c->cmt_no;
 610         }
 611
 612         err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
 613         if (err)
 614                 goto out_release;
 615         if (!sync) {
 616                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
 617
 618                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
 619                 ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
 620         }
 621         release_head(c, BASEHD);
 622         kfree(dent);
 623
 624         if (deletion) {
 625                 err = ubifs_tnc_remove_nm(c, &dent_key, nm);
 626                 if (err)
 627                         goto out_ro;
 628                 err = ubifs_add_dirt(c, lnum, dlen);
 629         } else
 630                 err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm);
 631         if (err)
 632                 goto out_ro;
 633
 634         /*
 635          * Note, we do not remove the inode from TNC even if the last reference
 636          * to it has just been deleted, because the inode may still be opened.
 637          * Instead, the inode has been added to orphan lists and the orphan
 638          * subsystem will take further care about it.
 639          */
 640         ino_key_init(c, &ino_key, inode->i_ino);
 641         ino_offs = dent_offs + aligned_dlen;
 642         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
 643         if (err)
 644                 goto out_ro;
 645
 646         ino_key_init(c, &ino_key, dir->i_ino);
 647         ino_offs += aligned_ilen;
 648         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ);
 649         if (err)
 650                 goto out_ro;
 651
 652         finish_reservation(c);
 653         spin_lock(&ui->ui_lock);
 654         ui->synced_i_size = ui->ui_size;
 655         spin_unlock(&ui->ui_lock);
 656         mark_inode_clean(c, ui);
 657         mark_inode_clean(c, dir_ui);
 658         return 0;
 659
 660 out_finish:
 661         finish_reservation(c);
 662 out_free:
 663         kfree(dent);
 664         return err;
 665
 666 out_release:
 667         release_head(c, BASEHD);
 668 out_ro:
 669         ubifs_ro_mode(c, err);
 670         if (last_reference)
 671                 ubifs_delete_orphan(c, inode->i_ino);
 672         finish_reservation(c);
 673         return err;
 674 }
 675
 676 /**
 677  * ubifs_jnl_write_data - write a data node to the journal.
 678  * @c: UBIFS file-system description object
 679  * @inode: inode the data node belongs to
 680  * @key: node key
 681  * @buf: buffer to write
 682  * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
 683  *
 684  * This function writes a data node to the journal. Returns %0 if the data node
 685  * was successfully written, and a negative error code in case of failure.
 686  */
 687 int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
 688                          const union ubifs_key *key, const void *buf, int len)
 689 {
 690         struct ubifs_data_node *data;
 691         int err, lnum, offs, compr_type, out_len;
 692         int dlen = UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR;
 693         struct ubifs_inode *ui = ubifs_inode(inode);
 694
 695         dbg_jnl("ino %lu, blk %u, len %d, key %s",
 696                 (unsigned long)key_inum(c, key), key_block(c, key), len,
 697                 DBGKEY(key));
 698         ubifs_assert(len <= UBIFS_BLOCK_SIZE);
 699
 700         data = kmalloc(dlen, GFP_NOFS);
 701         if (!data)
 702                 return -ENOMEM;
 703
 704         data->ch.node_type = UBIFS_DATA_NODE;
 705         key_write(c, key, &data->key);
 706         data->size = cpu_to_le32(len);
 707         zero_data_node_unused(data);
 708
 709         if (!(ui->flags & UBIFS_COMPR_FL))
 710                 /* Compression is disabled for this inode */
 711                 compr_type = UBIFS_COMPR_NONE;
 712         else
 713                 compr_type = ui->compr_type;
 714
 715         out_len = dlen - UBIFS_DATA_NODE_SZ;
 716         ubifs_compress(buf, len, &data->data, &out_len, &compr_type);
 717         ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
 718
 719         dlen = UBIFS_DATA_NODE_SZ + out_len;
 720         data->compr_type = cpu_to_le16(compr_type);
 721
 722         /* Make reservation before allocating sequence numbers */
 723         err = make_reservation(c, DATAHD, dlen);
 724         if (err)
 725                 goto out_free;
 726
 727         err = write_node(c, DATAHD, data, dlen, &lnum, &offs);
 728         if (err)
 729                 goto out_release;
 730         ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
 731         release_head(c, DATAHD);
 732
 733         err = ubifs_tnc_add(c, key, lnum, offs, dlen);
 734         if (err)
 735                 goto out_ro;
 736
 737         finish_reservation(c);
 738         kfree(data);
 739         return 0;
 740
 741 out_release:
 742         release_head(c, DATAHD);
 743 out_ro:
 744         ubifs_ro_mode(c, err);
 745         finish_reservation(c);
 746 out_free:
 747         kfree(data);
 748         return err;
 749 }
 750
 751 /**
 752  * ubifs_jnl_write_inode - flush inode to the journal.
 753  * @c: UBIFS file-system description object
 754  * @inode: inode to flush
 755  *
 756  * This function writes inode @inode to the journal. If the inode is
 757  * synchronous, it also synchronizes the write-buffer. Returns zero in case of
 758  * success and a negative error code in case of failure.
 759  */
 760 int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode)
 761 {
 762         int err, lnum, offs;
 763         struct ubifs_ino_node *ino;
 764         struct ubifs_inode *ui = ubifs_inode(inode);
 765         int sync = 0, len = UBIFS_INO_NODE_SZ, last_reference = !inode->i_nlink;
 766
 767         dbg_jnl("ino %lu, nlink %u", inode->i_ino, inode->i_nlink);
 768
 769         /*
 770          * If the inode is being deleted, do not write the attached data. No
 771          * need to synchronize the write-buffer either.
 772          */
 773         if (!last_reference) {
 774                 len += ui->data_len;
 775                 sync = IS_SYNC(inode);
 776         }
 777         ino = kmalloc(len, GFP_NOFS);
 778         if (!ino)
 779                 return -ENOMEM;
 780
 781         /* Make reservation before allocating sequence numbers */
 782         err = make_reservation(c, BASEHD, len);
 783         if (err)
 784                 goto out_free;
 785
 786         pack_inode(c, ino, inode, 1);
 787         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
 788         if (err)
 789                 goto out_release;
 790         if (!sync)
 791                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
 792                                           inode->i_ino);
 793         release_head(c, BASEHD);
 794
 795         if (last_reference) {
 796                 err = ubifs_tnc_remove_ino(c, inode->i_ino);
 797                 if (err)
 798                         goto out_ro;
 799                 ubifs_delete_orphan(c, inode->i_ino);
 800                 err = ubifs_add_dirt(c, lnum, len);
 801         } else {
 802                 union ubifs_key key;
 803
 804                 ino_key_init(c, &key, inode->i_ino);
 805                 err = ubifs_tnc_add(c, &key, lnum, offs, len);
 806         }
 807         if (err)
 808                 goto out_ro;
 809
 810         finish_reservation(c);
 811         spin_lock(&ui->ui_lock);
 812         ui->synced_i_size = ui->ui_size;
 813         spin_unlock(&ui->ui_lock);
 814         kfree(ino);
 815         return 0;
 816
 817 out_release:
 818         release_head(c, BASEHD);
 819 out_ro:
 820         ubifs_ro_mode(c, err);
 821         finish_reservation(c);
 822 out_free:
 823         kfree(ino);
 824         return err;
 825 }
 826
 827 /**
 828  * ubifs_jnl_delete_inode - delete an inode.
 829  * @c: UBIFS file-system description object
 830  * @inode: inode to delete
 831  *
 832  * This function deletes inode @inode which includes removing it from orphans,
 833  * deleting it from TNC and, in some cases, writing a deletion inode to the
 834  * journal.
 835  *
 836  * When regular file inodes are unlinked or a directory inode is removed, the
 837  * 'ubifs_jnl_update()' function writes a corresponding deletion inode and
 838  * direntry to the media, and adds the inode to orphans. After this, when the
 839  * last reference to this inode has been dropped, this function is called. In
 840  * general, it has to write one more deletion inode to the media, because if
 841  * a commit happened between 'ubifs_jnl_update()' and
 842  * 'ubifs_jnl_delete_inode()', the deletion inode is not in the journal
 843  * anymore, and in fact it might not be on the flash anymore, because it might
 844  * have been garbage-collected already. And for optimization reasons UBIFS does
 845  * not read the orphan area if it has been unmounted cleanly, so it would have
 846  * no indication in the journal that there is a deleted inode which has to be
 847  * removed from TNC.
 848  *
 849  * However, if there was no commit between 'ubifs_jnl_update()' and
 850  * 'ubifs_jnl_delete_inode()', then there is no need to write the deletion
 851  * inode to the media for the second time. And this is quite a typical case.
 852  *
 853  * This function returns zero in case of success and a negative error code in
 854  * case of failure.
 855  */
 856 int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode)
 857 {
 858         int err;
 859         struct ubifs_inode *ui = ubifs_inode(inode);
 860
 861         ubifs_assert(inode->i_nlink == 0);
 862
 863         if (ui->del_cmtno != c->cmt_no)
 864                 /* A commit happened for sure */
 865                 return ubifs_jnl_write_inode(c, inode);
 866
 867         down_read(&c->commit_sem);
 868         /*
 869          * Check commit number again, because the first test has been done
 870          * without @c->commit_sem, so a commit might have happened.
 871          */
 872         if (ui->del_cmtno != c->cmt_no) {
 873                 up_read(&c->commit_sem);
 874                 return ubifs_jnl_write_inode(c, inode);
 875         }
 876
 877         err = ubifs_tnc_remove_ino(c, inode->i_ino);
 878         if (err)
 879                 ubifs_ro_mode(c, err);
 880         else
 881                 ubifs_delete_orphan(c, inode->i_ino);
 882         up_read(&c->commit_sem);
 883         return err;
 884 }
 885
 886 /**
 887  * ubifs_jnl_rename - rename a directory entry.
 888  * @c: UBIFS file-system description object
 889  * @old_dir: parent inode of directory entry to rename
 890  * @old_dentry: directory entry to rename
 891  * @new_dir: parent inode of directory entry to rename
 892  * @new_dentry: new directory entry (or directory entry to replace)
 893  * @sync: non-zero if the write-buffer has to be synchronized
 894  *
 895  * This function implements the re-name operation which may involve writing up
 896  * to 3 inodes and 2 directory entries. It marks the written inodes as clean
 897  * and returns zero on success. In case of failure, a negative error code is
 898  * returned.
 899  */
 900 int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
 901                      const struct dentry *old_dentry,
 902                      const struct inode *new_dir,
 903                      const struct dentry *new_dentry, int sync)
 904 {
 905         void *p;
 906         union ubifs_key key;
 907         struct ubifs_dent_node *dent, *dent2;
 908         int err, dlen1, dlen2, ilen, lnum, offs, len;
 909         const struct inode *old_inode = old_dentry->d_inode;
 910         const struct inode *new_inode = new_dentry->d_inode;
 911         int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
 912         int last_reference = !!(new_inode && new_inode->i_nlink == 0);
 913         int move = (old_dir != new_dir);
 914         struct ubifs_inode *uninitialized_var(new_ui);
 915
 916         dbg_jnl("dent '%.*s' in dir ino %lu to dent '%.*s' in dir ino %lu",
 917                 old_dentry->d_name.len, old_dentry->d_name.name,
 918                 old_dir->i_ino, new_dentry->d_name.len,
 919                 new_dentry->d_name.name, new_dir->i_ino);
 920         ubifs_assert(ubifs_inode(old_dir)->data_len == 0);
 921         ubifs_assert(ubifs_inode(new_dir)->data_len == 0);
 922         ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
 923         ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
 924
 925         dlen1 = UBIFS_DENT_NODE_SZ + new_dentry->d_name.len + 1;
 926         dlen2 = UBIFS_DENT_NODE_SZ + old_dentry->d_name.len + 1;
 927         if (new_inode) {
 928                 new_ui = ubifs_inode(new_inode);
 929                 ubifs_assert(mutex_is_locked(&new_ui->ui_mutex));
 930                 ilen = UBIFS_INO_NODE_SZ;
 931                 if (!last_reference)
 932                         ilen += new_ui->data_len;
 933         } else
 934                 ilen = 0;
 935
 936         aligned_dlen1 = ALIGN(dlen1, 8);
 937         aligned_dlen2 = ALIGN(dlen2, 8);
 938         len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8);
 939         if (old_dir != new_dir)
 940                 len += plen;
 941         dent = kmalloc(len, GFP_NOFS);
 942         if (!dent)
 943                 return -ENOMEM;
 944
 945         /* Make reservation before allocating sequence numbers */
 946         err = make_reservation(c, BASEHD, len);
 947         if (err)
 948                 goto out_free;
 949
 950         /* Make new dent */
 951         dent->ch.node_type = UBIFS_DENT_NODE;
 952         dent_key_init_flash(c, &dent->key, new_dir->i_ino, &new_dentry->d_name);
 953         dent->inum = cpu_to_le64(old_inode->i_ino);
 954         dent->type = get_dent_type(old_inode->i_mode);
 955         dent->nlen = cpu_to_le16(new_dentry->d_name.len);
 956         memcpy(dent->name, new_dentry->d_name.name, new_dentry->d_name.len);
 957         dent->name[new_dentry->d_name.len] = '\0';
 958         zero_dent_node_unused(dent);
 959         ubifs_prep_grp_node(c, dent, dlen1, 0);
 960
 961         /* Make deletion dent */
 962         dent2 = (void *)dent + aligned_dlen1;
 963         dent2->ch.node_type = UBIFS_DENT_NODE;
 964         dent_key_init_flash(c, &dent2->key, old_dir->i_ino,
 965                             &old_dentry->d_name);
 966         dent2->inum = 0;
 967         dent2->type = DT_UNKNOWN;
 968         dent2->nlen = cpu_to_le16(old_dentry->d_name.len);
 969         memcpy(dent2->name, old_dentry->d_name.name, old_dentry->d_name.len);
 970         dent2->name[old_dentry->d_name.len] = '\0';
 971         zero_dent_node_unused(dent2);
 972         ubifs_prep_grp_node(c, dent2, dlen2, 0);
 973
 974         p = (void *)dent2 + aligned_dlen2;
 975         if (new_inode) {
 976                 pack_inode(c, p, new_inode, 0);
 977                 p += ALIGN(ilen, 8);
 978         }
 979
 980         if (!move)
 981                 pack_inode(c, p, old_dir, 1);
 982         else {
 983                 pack_inode(c, p, old_dir, 0);
 984                 p += ALIGN(plen, 8);
 985                 pack_inode(c, p, new_dir, 1);
 986         }
 987
 988         if (last_reference) {
 989                 err = ubifs_add_orphan(c, new_inode->i_ino);
 990                 if (err) {
 991                         release_head(c, BASEHD);
 992                         goto out_finish;
 993                 }
 994                 new_ui->del_cmtno = c->cmt_no;
 995         }
 996
 997         err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
 998         if (err)
 999                 goto out_release;
1000         if (!sync) {
1001                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1002
1003                 ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
1004                 ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
1005                 if (new_inode)
1006                         ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
1007                                                   new_inode->i_ino);
1008         }
1009         release_head(c, BASEHD);
1010
1011         dent_key_init(c, &key, new_dir->i_ino, &new_dentry->d_name);
1012         err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &new_dentry->d_name);
1013         if (err)
1014                 goto out_ro;
1015
1016         err = ubifs_add_dirt(c, lnum, dlen2);
1017         if (err)
1018                 goto out_ro;
1019
1020         dent_key_init(c, &key, old_dir->i_ino, &old_dentry->d_name);
1021         err = ubifs_tnc_remove_nm(c, &key, &old_dentry->d_name);
1022         if (err)
1023                 goto out_ro;
1024
1025         offs += aligned_dlen1 + aligned_dlen2;
1026         if (new_inode) {
1027                 ino_key_init(c, &key, new_inode->i_ino);
1028                 err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
1029                 if (err)
1030                         goto out_ro;
1031                 offs += ALIGN(ilen, 8);
1032         }
1033
1034         ino_key_init(c, &key, old_dir->i_ino);
1035         err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1036         if (err)
1037                 goto out_ro;
1038
1039         if (old_dir != new_dir) {
1040                 offs += ALIGN(plen, 8);
1041                 ino_key_init(c, &key, new_dir->i_ino);
1042                 err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1043                 if (err)
1044                         goto out_ro;
1045         }
1046
1047         finish_reservation(c);
1048         if (new_inode) {
1049                 mark_inode_clean(c, new_ui);
1050                 spin_lock(&new_ui->ui_lock);
1051                 new_ui->synced_i_size = new_ui->ui_size;
1052                 spin_unlock(&new_ui->ui_lock);
1053         }
1054         mark_inode_clean(c, ubifs_inode(old_dir));
1055         if (move)
1056                 mark_inode_clean(c, ubifs_inode(new_dir));
1057         kfree(dent);
1058         return 0;
1059
1060 out_release:
1061         release_head(c, BASEHD);
1062 out_ro:
1063         ubifs_ro_mode(c, err);
1064         if (last_reference)
1065                 ubifs_delete_orphan(c, new_inode->i_ino);
1066 out_finish:
1067         finish_reservation(c);
1068 out_free:
1069         kfree(dent);
1070         return err;
1071 }
1072
1073 /**
1074  * recomp_data_node - re-compress a truncated data node.
1075  * @dn: data node to re-compress
1076  * @new_len: new length
1077  *
1078  * This function is used when an inode is truncated and the last data node of
1079  * the inode has to be re-compressed and re-written.
1080  */
1081 static int recomp_data_node(struct ubifs_data_node *dn, int *new_len)
1082 {
1083         void *buf;
1084         int err, len, compr_type, out_len;
1085
1086         out_len = le32_to_cpu(dn->size);
1087         buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
1088         if (!buf)
1089                 return -ENOMEM;
1090
1091         len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
1092         compr_type = le16_to_cpu(dn->compr_type);
1093         err = ubifs_decompress(&dn->data, len, buf, &out_len, compr_type);
1094         if (err)
1095                 goto out;
1096
1097         ubifs_compress(buf, *new_len, &dn->data, &out_len, &compr_type);
1098         ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
1099         dn->compr_type = cpu_to_le16(compr_type);
1100         dn->size = cpu_to_le32(*new_len);
1101         *new_len = UBIFS_DATA_NODE_SZ + out_len;
1102 out:
1103         kfree(buf);
1104         return err;
1105 }
1106
1107 /**
1108  * ubifs_jnl_truncate - update the journal for a truncation.
1109  * @c: UBIFS file-system description object
1110  * @inode: inode to truncate
1111  * @old_size: old size
1112  * @new_size: new size
1113  *
1114  * When the size of a file decreases due to truncation, a truncation node is
1115  * written, the journal tree is updated, and the last data block is re-written
1116  * if it has been affected. The inode is also updated in order to synchronize
1117  * the new inode size.
1118  *
1119  * This function marks the inode as clean and returns zero on success. In case
1120  * of failure, a negative error code is returned.
1121  */
1122 int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1123                        loff_t old_size, loff_t new_size)
1124 {
1125         union ubifs_key key, to_key;
1126         struct ubifs_ino_node *ino;
1127         struct ubifs_trun_node *trun;
1128         struct ubifs_data_node *uninitialized_var(dn);
1129         int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
1130         struct ubifs_inode *ui = ubifs_inode(inode);
1131         ino_t inum = inode->i_ino;
1132         unsigned int blk;
1133
1134         dbg_jnl("ino %lu, size %lld -> %lld",
1135                 (unsigned long)inum, old_size, new_size);
1136         ubifs_assert(!ui->data_len);
1137         ubifs_assert(S_ISREG(inode->i_mode));
1138         ubifs_assert(mutex_is_locked(&ui->ui_mutex));
1139
1140         sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
1141              UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
1142         ino = kmalloc(sz, GFP_NOFS);
1143         if (!ino)
1144                 return -ENOMEM;
1145
1146         trun = (void *)ino + UBIFS_INO_NODE_SZ;
1147         trun->ch.node_type = UBIFS_TRUN_NODE;
1148         trun->inum = cpu_to_le32(inum);
1149         trun->old_size = cpu_to_le64(old_size);
1150         trun->new_size = cpu_to_le64(new_size);
1151         zero_trun_node_unused(trun);
1152
1153         dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
1154         if (dlen) {
1155                 /* Get last data block so it can be truncated */
1156                 dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
1157                 blk = new_size >> UBIFS_BLOCK_SHIFT;
1158                 data_key_init(c, &key, inum, blk);
1159                 dbg_jnl("last block key %s", DBGKEY(&key));
1160                 err = ubifs_tnc_lookup(c, &key, dn);
1161                 if (err == -ENOENT)
1162                         dlen = 0; /* Not found (so it is a hole) */
1163                 else if (err)
1164                         goto out_free;
1165                 else {
1166                         if (le32_to_cpu(dn->size) <= dlen)
1167                                 dlen = 0; /* Nothing to do */
1168                         else {
1169                                 int compr_type = le16_to_cpu(dn->compr_type);
1170
1171                                 if (compr_type != UBIFS_COMPR_NONE) {
1172                                         err = recomp_data_node(dn, &dlen);
1173                                         if (err)
1174                                                 goto out_free;
1175                                 } else {
1176                                         dn->size = cpu_to_le32(dlen);
1177                                         dlen += UBIFS_DATA_NODE_SZ;
1178                                 }
1179                                 zero_data_node_unused(dn);
1180                         }
1181                 }
1182         }
1183
1184         /* Must make reservation before allocating sequence numbers */
1185         len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
1186         if (dlen)
1187                 len += dlen;
1188         err = make_reservation(c, BASEHD, len);
1189         if (err)
1190                 goto out_free;
1191
1192         pack_inode(c, ino, inode, 0);
1193         ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
1194         if (dlen)
1195                 ubifs_prep_grp_node(c, dn, dlen, 1);
1196
1197         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
1198         if (err)
1199                 goto out_release;
1200         if (!sync)
1201                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
1202         release_head(c, BASEHD);
1203
1204         if (dlen) {
1205                 sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
1206                 err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
1207                 if (err)
1208                         goto out_ro;
1209         }
1210
1211         ino_key_init(c, &key, inum);
1212         err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
1213         if (err)
1214                 goto out_ro;
1215
1216         err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
1217         if (err)
1218                 goto out_ro;
1219
1220         bit = new_size & (UBIFS_BLOCK_SIZE - 1);
1221         blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
1222         data_key_init(c, &key, inum, blk);
1223
1224         bit = old_size & (UBIFS_BLOCK_SIZE - 1);
1225         blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0 : 1);
1226         data_key_init(c, &to_key, inum, blk);
1227
1228         err = ubifs_tnc_remove_range(c, &key, &to_key);
1229         if (err)
1230                 goto out_ro;
1231
1232         finish_reservation(c);
1233         spin_lock(&ui->ui_lock);
1234         ui->synced_i_size = ui->ui_size;
1235         spin_unlock(&ui->ui_lock);
1236         mark_inode_clean(c, ui);
1237         kfree(ino);
1238         return 0;
1239
1240 out_release:
1241         release_head(c, BASEHD);
1242 out_ro:
1243         ubifs_ro_mode(c, err);
1244         finish_reservation(c);
1245 out_free:
1246         kfree(ino);
1247         return err;
1248 }
1249
1250 #ifdef CONFIG_UBIFS_FS_XATTR
1251
1252 /**
1253  * ubifs_jnl_delete_xattr - delete an extended attribute.
1254  * @c: UBIFS file-system description object
1255  * @host: host inode
1256  * @inode: extended attribute inode
1257  * @nm: extended attribute entry name
1258  *
1259  * This function delete an extended attribute which is very similar to
1260  * un-linking regular files - it writes a deletion xentry, a deletion inode and
1261  * updates the target inode. Returns zero in case of success and a negative
1262  * error code in case of failure.
1263  */
1264 int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1265                            const struct inode *inode, const struct qstr *nm)
1266 {
1267         int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
1268         struct ubifs_dent_node *xent;
1269         struct ubifs_ino_node *ino;
1270         union ubifs_key xent_key, key1, key2;
1271         int sync = IS_DIRSYNC(host);
1272         struct ubifs_inode *host_ui = ubifs_inode(host);
1273
1274         dbg_jnl("host %lu, xattr ino %lu, name '%s', data len %d",
1275                 host->i_ino, inode->i_ino, nm->name,
1276                 ubifs_inode(inode)->data_len);
1277         ubifs_assert(inode->i_nlink == 0);
1278         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1279
1280         /*
1281          * Since we are deleting the inode, we do not bother to attach any data
1282          * to it and assume its length is %UBIFS_INO_NODE_SZ.
1283          */
1284         xlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
1285         aligned_xlen = ALIGN(xlen, 8);
1286         hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
1287         len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
1288
1289         xent = kmalloc(len, GFP_NOFS);
1290         if (!xent)
1291                 return -ENOMEM;
1292
1293         /* Make reservation before allocating sequence numbers */
1294         err = make_reservation(c, BASEHD, len);
1295         if (err) {
1296                 kfree(xent);
1297                 return err;
1298         }
1299
1300         xent->ch.node_type = UBIFS_XENT_NODE;
1301         xent_key_init(c, &xent_key, host->i_ino, nm);
1302         key_write(c, &xent_key, xent->key);
1303         xent->inum = 0;
1304         xent->type = get_dent_type(inode->i_mode);
1305         xent->nlen = cpu_to_le16(nm->len);
1306         memcpy(xent->name, nm->name, nm->len);
1307         xent->name[nm->len] = '\0';
1308         zero_dent_node_unused(xent);
1309         ubifs_prep_grp_node(c, xent, xlen, 0);
1310
1311         ino = (void *)xent + aligned_xlen;
1312         pack_inode(c, ino, inode, 0);
1313         ino = (void *)ino + UBIFS_INO_NODE_SZ;
1314         pack_inode(c, ino, host, 1);
1315
1316         err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
1317         if (!sync && !err)
1318                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
1319         release_head(c, BASEHD);
1320         kfree(xent);
1321         if (err)
1322                 goto out_ro;
1323
1324         /* Remove the extended attribute entry from TNC */
1325         err = ubifs_tnc_remove_nm(c, &xent_key, nm);
1326         if (err)
1327                 goto out_ro;
1328         err = ubifs_add_dirt(c, lnum, xlen);
1329         if (err)
1330                 goto out_ro;
1331
1332         /*
1333          * Remove all nodes belonging to the extended attribute inode from TNC.
1334          * Well, there actually must be only one node - the inode itself.
1335          */
1336         lowest_ino_key(c, &key1, inode->i_ino);
1337         highest_ino_key(c, &key2, inode->i_ino);
1338         err = ubifs_tnc_remove_range(c, &key1, &key2);
1339         if (err)
1340                 goto out_ro;
1341         err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
1342         if (err)
1343                 goto out_ro;
1344
1345         /* And update TNC with the new host inode position */
1346         ino_key_init(c, &key1, host->i_ino);
1347         err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
1348         if (err)
1349                 goto out_ro;
1350
1351         finish_reservation(c);
1352         spin_lock(&host_ui->ui_lock);
1353         host_ui->synced_i_size = host_ui->ui_size;
1354         spin_unlock(&host_ui->ui_lock);
1355         mark_inode_clean(c, host_ui);
1356         return 0;
1357
1358 out_ro:
1359         ubifs_ro_mode(c, err);
1360         finish_reservation(c);
1361         return err;
1362 }
1363
1364 /**
1365  * ubifs_jnl_change_xattr - change an extended attribute.
1366  * @c: UBIFS file-system description object
1367  * @inode: extended attribute inode
1368  * @host: host inode
1369  *
1370  * This function writes the updated version of an extended attribute inode and
1371  * the host inode to the journal (to the base head). The host inode is written
1372  * after the extended attribute inode in order to guarantee that the extended
1373  * attribute will be flushed when the inode is synchronized by 'fsync()' and
1374  * consequently, the write-buffer is synchronized. This function returns zero
1375  * in case of success and a negative error code in case of failure.
1376  */
1377 int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
1378                            const struct inode *host)
1379 {
1380         int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
1381         struct ubifs_inode *host_ui = ubifs_inode(host);
1382         struct ubifs_ino_node *ino;
1383         union ubifs_key key;
1384         int sync = IS_DIRSYNC(host);
1385
1386         dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
1387         ubifs_assert(host->i_nlink > 0);
1388         ubifs_assert(inode->i_nlink > 0);
1389         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1390
1391         len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
1392         len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
1393         aligned_len1 = ALIGN(len1, 8);
1394         aligned_len = aligned_len1 + ALIGN(len2, 8);
1395
1396         ino = kmalloc(aligned_len, GFP_NOFS);
1397         if (!ino)
1398                 return -ENOMEM;
1399
1400         /* Make reservation before allocating sequence numbers */
1401         err = make_reservation(c, BASEHD, aligned_len);
1402         if (err)
1403                 goto out_free;
1404
1405         pack_inode(c, ino, host, 0);
1406         pack_inode(c, (void *)ino + aligned_len1, inode, 1);
1407
1408         err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
1409         if (!sync && !err) {
1410                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1411
1412                 ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
1413                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
1414         }
1415         release_head(c, BASEHD);
1416         if (err)
1417                 goto out_ro;
1418
1419         ino_key_init(c, &key, host->i_ino);
1420         err = ubifs_tnc_add(c, &key, lnum, offs, len1);
1421         if (err)
1422                 goto out_ro;
1423
1424         ino_key_init(c, &key, inode->i_ino);
1425         err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
1426         if (err)
1427                 goto out_ro;
1428
1429         finish_reservation(c);
1430         spin_lock(&host_ui->ui_lock);
1431         host_ui->synced_i_size = host_ui->ui_size;
1432         spin_unlock(&host_ui->ui_lock);
1433         mark_inode_clean(c, host_ui);
1434         kfree(ino);
1435         return 0;
1436
1437 out_ro:
1438         ubifs_ro_mode(c, err);
1439         finish_reservation(c);
1440 out_free:
1441         kfree(ino);
1442         return err;
1443 }
1444
1445 #endif /* CONFIG_UBIFS_FS_XATTR */