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         ubifs_assert(!c->ro_media && !c->ro_mount);
 126         squeeze = (jhead == BASEHD);
 127 again:
 128         mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 129
 130         if (c->ro_error) {
 131                 err = -EROFS;
 132                 goto out_unlock;
 133         }
 134
 135         avail = c->leb_size - wbuf->offs - wbuf->used;
 136         if (wbuf->lnum != -1 && avail >= len)
 137                 return 0;
 138
 139         /*
 140          * Write buffer wasn't seek'ed or there is no enough space - look for an
 141          * LEB with some empty space.
 142          */
 143         lnum = ubifs_find_free_space(c, len, &offs, squeeze);
 144         if (lnum >= 0) {
 145                 /* Found an LEB, add it to the journal head */
 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 in jhead %s, run GC", dbg_jhead(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 %s",
 178                         dbg_jhead(jhead));
 179                 if (retries++ < 2) {
 180                         dbg_jnl("retry (%d)", retries);
 181                         goto again;
 182                 }
 183
 184                 dbg_jnl("return -ENOSPC");
 185                 return err;
 186         }
 187
 188         mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 189         dbg_jnl("got LEB %d for jhead %s", lnum, dbg_jhead(jhead));
 190         avail = c->leb_size - wbuf->offs - wbuf->used;
 191
 192         if (wbuf->lnum != -1 && avail >= len) {
 193                 /*
 194                  * Someone else has switched the journal head and we have
 195                  * enough space now. This happens when more than one process is
 196                  * trying to write to the same journal head at the same time.
 197                  */
 198                 dbg_jnl("return LEB %d back, already have LEB %d:%d",
 199                         lnum, wbuf->lnum, wbuf->offs + wbuf->used);
 200                 err = ubifs_return_leb(c, lnum);
 201                 if (err)
 202                         goto out_unlock;
 203                 return 0;
 204         }
 205
 206         err = ubifs_add_bud_to_log(c, jhead, lnum, 0);
 207         if (err)
 208                 goto out_return;
 209         offs = 0;
 210
 211 out:
 212         err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs, wbuf->dtype);
 213         if (err)
 214                 goto out_unlock;
 215
 216         return 0;
 217
 218 out_unlock:
 219         mutex_unlock(&wbuf->io_mutex);
 220         return err;
 221
 222 out_return:
 223         /* An error occurred and the LEB has to be returned to lprops */
 224         ubifs_assert(err < 0);
 225         err1 = ubifs_return_leb(c, lnum);
 226         if (err1 && err == -EAGAIN)
 227                 /*
 228                  * Return original error code only if it is not %-EAGAIN,
 229                  * which is not really an error. Otherwise, return the error
 230                  * code of 'ubifs_return_leb()'.
 231                  */
 232                 err = err1;
 233         mutex_unlock(&wbuf->io_mutex);
 234         return err;
 235 }
 236
 237 /**
 238  * write_node - write node to a journal head.
 239  * @c: UBIFS file-system description object
 240  * @jhead: journal head
 241  * @node: node to write
 242  * @len: node length
 243  * @lnum: LEB number written is returned here
 244  * @offs: offset written is returned here
 245  *
 246  * This function writes a node to reserved space of journal head @jhead.
 247  * Returns zero in case of success and a negative error code in case of
 248  * failure.
 249  */
 250 static int write_node(struct ubifs_info *c, int jhead, void *node, int len,
 251                       int *lnum, int *offs)
 252 {
 253         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 254
 255         ubifs_assert(jhead != GCHD);
 256
 257         *lnum = c->jheads[jhead].wbuf.lnum;
 258         *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 259
 260         dbg_jnl("jhead %s, LEB %d:%d, len %d",
 261                 dbg_jhead(jhead), *lnum, *offs, len);
 262         ubifs_prepare_node(c, node, len, 0);
 263
 264         return ubifs_wbuf_write_nolock(wbuf, node, len);
 265 }
 266
 267 /**
 268  * write_head - write data to a journal head.
 269  * @c: UBIFS file-system description object
 270  * @jhead: journal head
 271  * @buf: buffer to write
 272  * @len: length to write
 273  * @lnum: LEB number written is returned here
 274  * @offs: offset written is returned here
 275  * @sync: non-zero if the write-buffer has to by synchronized
 276  *
 277  * This function is the same as 'write_node()' but it does not assume the
 278  * buffer it is writing is a node, so it does not prepare it (which means
 279  * initializing common header and calculating CRC).
 280  */
 281 static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
 282                       int *lnum, int *offs, int sync)
 283 {
 284         int err;
 285         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 286
 287         ubifs_assert(jhead != GCHD);
 288
 289         *lnum = c->jheads[jhead].wbuf.lnum;
 290         *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 291         dbg_jnl("jhead %s, LEB %d:%d, len %d",
 292                 dbg_jhead(jhead), *lnum, *offs, len);
 293
 294         err = ubifs_wbuf_write_nolock(wbuf, buf, len);
 295         if (err)
 296                 return err;
 297         if (sync)
 298                 err = ubifs_wbuf_sync_nolock(wbuf);
 299         return err;
 300 }
 301
 302 /**
 303  * make_reservation - reserve journal space.
 304  * @c: UBIFS file-system description object
 305  * @jhead: journal head
 306  * @len: how many bytes to reserve
 307  *
 308  * This function makes space reservation in journal head @jhead. The function
 309  * takes the commit lock and locks the journal head, and the caller has to
 310  * unlock the head and finish the reservation with 'finish_reservation()'.
 311  * Returns zero in case of success and a negative error code in case of
 312  * failure.
 313  *
 314  * Note, the journal head may be unlocked as soon as the data is written, while
 315  * the commit lock has to be released after the data has been added to the
 316  * TNC.
 317  */
 318 static int make_reservation(struct ubifs_info *c, int jhead, int len)
 319 {
 320         int err, cmt_retries = 0, nospc_retries = 0;
 321
 322 again:
 323         down_read(&c->commit_sem);
 324         err = reserve_space(c, jhead, len);
 325         if (!err)
 326                 return 0;
 327         up_read(&c->commit_sem);
 328
 329         if (err == -ENOSPC) {
 330                 /*
 331                  * GC could not make any progress. We should try to commit
 332                  * once because it could make some dirty space and GC would
 333                  * make progress, so make the error -EAGAIN so that the below
 334                  * will commit and re-try.
 335                  */
 336                 if (nospc_retries++ < 2) {
 337                         dbg_jnl("no space, retry");
 338                         err = -EAGAIN;
 339                 }
 340
 341                 /*
 342                  * This means that the budgeting is incorrect. We always have
 343                  * to be able to write to the media, because all operations are
 344                  * budgeted. Deletions are not budgeted, though, but we reserve
 345                  * an extra LEB for them.
 346                  */
 347         }
 348
 349         if (err != -EAGAIN)
 350                 goto out;
 351
 352         /*
 353          * -EAGAIN means that the journal is full or too large, or the above
 354          * code wants to do one commit. Do this and re-try.
 355          */
 356         if (cmt_retries > 128) {
 357                 /*
 358                  * This should not happen unless the journal size limitations
 359                  * are too tough.
 360                  */
 361                 ubifs_err("stuck in space allocation");
 362                 err = -ENOSPC;
 363                 goto out;
 364         } else if (cmt_retries > 32)
 365                 ubifs_warn("too many space allocation re-tries (%d)",
 366                            cmt_retries);
 367
 368         dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
 369                 cmt_retries);
 370         cmt_retries += 1;
 371
 372         err = ubifs_run_commit(c);
 373         if (err)
 374                 return err;
 375         goto again;
 376
 377 out:
 378         ubifs_err("cannot reserve %d bytes in jhead %d, error %d",
 379                   len, jhead, err);
 380         if (err == -ENOSPC) {
 381                 /* This are some budgeting problems, print useful information */
 382                 down_write(&c->commit_sem);
 383                 spin_lock(&c->space_lock);
 384                 dbg_dump_stack();
 385                 dbg_dump_budg(c);
 386                 spin_unlock(&c->space_lock);
 387                 dbg_dump_lprops(c);
 388                 cmt_retries = dbg_check_lprops(c);
 389                 up_write(&c->commit_sem);
 390         }
 391         return err;
 392 }
 393
 394 /**
 395  * release_head - release a journal head.
 396  * @c: UBIFS file-system description object
 397  * @jhead: journal head
 398  *
 399  * This function releases journal head @jhead which was locked by
 400  * the 'make_reservation()' function. It has to be called after each successful
 401  * 'make_reservation()' invocation.
 402  */
 403 static inline void release_head(struct ubifs_info *c, int jhead)
 404 {
 405         mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
 406 }
 407
 408 /**
 409  * finish_reservation - finish a reservation.
 410  * @c: UBIFS file-system description object
 411  *
 412  * This function finishes journal space reservation. It must be called after
 413  * 'make_reservation()'.
 414  */
 415 static void finish_reservation(struct ubifs_info *c)
 416 {
 417         up_read(&c->commit_sem);
 418 }
 419
 420 /**
 421  * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
 422  * @mode: inode mode
 423  */
 424 static int get_dent_type(int mode)
 425 {
 426         switch (mode & S_IFMT) {
 427         case S_IFREG:
 428                 return UBIFS_ITYPE_REG;
 429         case S_IFDIR:
 430                 return UBIFS_ITYPE_DIR;
 431         case S_IFLNK:
 432                 return UBIFS_ITYPE_LNK;
 433         case S_IFBLK:
 434                 return UBIFS_ITYPE_BLK;
 435         case S_IFCHR:
 436                 return UBIFS_ITYPE_CHR;
 437         case S_IFIFO:
 438                 return UBIFS_ITYPE_FIFO;
 439         case S_IFSOCK:
 440                 return UBIFS_ITYPE_SOCK;
 441         default:
 442                 BUG();
 443         }
 444         return 0;
 445 }
 446
 447 /**
 448  * pack_inode - pack an inode node.
 449  * @c: UBIFS file-system description object
 450  * @ino: buffer in which to pack inode node
 451  * @inode: inode to pack
 452  * @last: indicates the last node of the group
 453  */
 454 static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
 455                        const struct inode *inode, int last)
 456 {
 457         int data_len = 0, last_reference = !inode->i_nlink;
 458         struct ubifs_inode *ui = ubifs_inode(inode);
 459
 460         ino->ch.node_type = UBIFS_INO_NODE;
 461         ino_key_init_flash(c, &ino->key, inode->i_ino);
 462         ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum);
 463         ino->atime_sec  = cpu_to_le64(inode->i_atime.tv_sec);
 464         ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
 465         ino->ctime_sec  = cpu_to_le64(inode->i_ctime.tv_sec);
 466         ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 467         ino->mtime_sec  = cpu_to_le64(inode->i_mtime.tv_sec);
 468         ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 469         ino->uid   = cpu_to_le32(inode->i_uid);
 470         ino->gid   = cpu_to_le32(inode->i_gid);
 471         ino->mode  = cpu_to_le32(inode->i_mode);
 472         ino->flags = cpu_to_le32(ui->flags);
 473         ino->size  = cpu_to_le64(ui->ui_size);
 474         ino->nlink = cpu_to_le32(inode->i_nlink);
 475         ino->compr_type  = cpu_to_le16(ui->compr_type);
 476         ino->data_len    = cpu_to_le32(ui->data_len);
 477         ino->xattr_cnt   = cpu_to_le32(ui->xattr_cnt);
 478         ino->xattr_size  = cpu_to_le32(ui->xattr_size);
 479         ino->xattr_names = cpu_to_le32(ui->xattr_names);
 480         zero_ino_node_unused(ino);
 481
 482         /*
 483          * Drop the attached data if this is a deletion inode, the data is not
 484          * needed anymore.
 485          */
 486         if (!last_reference) {
 487                 memcpy(ino->data, ui->data, ui->data_len);
 488                 data_len = ui->data_len;
 489         }
 490
 491         ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last);
 492 }
 493
 494 /**
 495  * mark_inode_clean - mark UBIFS inode as clean.
 496  * @c: UBIFS file-system description object
 497  * @ui: UBIFS inode to mark as clean
 498  *
 499  * This helper function marks UBIFS inode @ui as clean by cleaning the
 500  * @ui->dirty flag and releasing its budget. Note, VFS may still treat the
 501  * inode as dirty and try to write it back, but 'ubifs_write_inode()' would
 502  * just do nothing.
 503  */
 504 static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui)
 505 {
 506         if (ui->dirty)
 507                 ubifs_release_dirty_inode_budget(c, ui);
 508         ui->dirty = 0;
 509 }
 510
 511 /**
 512  * ubifs_jnl_update - update inode.
 513  * @c: UBIFS file-system description object
 514  * @dir: parent inode or host inode in case of extended attributes
 515  * @nm: directory entry name
 516  * @inode: inode to update
 517  * @deletion: indicates a directory entry deletion i.e unlink or rmdir
 518  * @xent: non-zero if the directory entry is an extended attribute entry
 519  *
 520  * This function updates an inode by writing a directory entry (or extended
 521  * attribute entry), the inode itself, and the parent directory inode (or the
 522  * host inode) to the journal.
 523  *
 524  * The function writes the host inode @dir last, which is important in case of
 525  * extended attributes. Indeed, then we guarantee that if the host inode gets
 526  * synchronized (with 'fsync()'), and the write-buffer it sits in gets flushed,
 527  * the extended attribute inode gets flushed too. And this is exactly what the
 528  * user expects - synchronizing the host inode synchronizes its extended
 529  * attributes. Similarly, this guarantees that if @dir is synchronized, its
 530  * directory entry corresponding to @nm gets synchronized too.
 531  *
 532  * If the inode (@inode) or the parent directory (@dir) are synchronous, this
 533  * function synchronizes the write-buffer.
 534  *
 535  * This function marks the @dir and @inode inodes as clean and returns zero on
 536  * success. In case of failure, a negative error code is returned.
 537  */
 538 int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
 539                      const struct qstr *nm, const struct inode *inode,
 540                      int deletion, int xent)
 541 {
 542         int err, dlen, ilen, len, lnum, ino_offs, dent_offs;
 543         int aligned_dlen, aligned_ilen, sync = IS_DIRSYNC(dir);
 544         int last_reference = !!(deletion && inode->i_nlink == 0);
 545         struct ubifs_inode *ui = ubifs_inode(inode);
 546         struct ubifs_inode *dir_ui = ubifs_inode(dir);
 547         struct ubifs_dent_node *dent;
 548         struct ubifs_ino_node *ino;
 549         union ubifs_key dent_key, ino_key;
 550
 551         dbg_jnl("ino %lu, dent '%.*s', data len %d in dir ino %lu",
 552                 inode->i_ino, nm->len, nm->name, ui->data_len, dir->i_ino);
 553         ubifs_assert(dir_ui->data_len == 0);
 554         ubifs_assert(mutex_is_locked(&dir_ui->ui_mutex));
 555
 556         dlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
 557         ilen = UBIFS_INO_NODE_SZ;
 558
 559         /*
 560          * If the last reference to the inode is being deleted, then there is
 561          * no need to attach and write inode data, it is being deleted anyway.
 562          * And if the inode is being deleted, no need to synchronize
 563          * write-buffer even if the inode is synchronous.
 564          */
 565         if (!last_reference) {
 566                 ilen += ui->data_len;
 567                 sync |= IS_SYNC(inode);
 568         }
 569
 570         aligned_dlen = ALIGN(dlen, 8);
 571         aligned_ilen = ALIGN(ilen, 8);
 572         len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ;
 573         dent = kmalloc(len, GFP_NOFS);
 574         if (!dent)
 575                 return -ENOMEM;
 576
 577         /* Make reservation before allocating sequence numbers */
 578         err = make_reservation(c, BASEHD, len);
 579         if (err)
 580                 goto out_free;
 581
 582         if (!xent) {
 583                 dent->ch.node_type = UBIFS_DENT_NODE;
 584                 dent_key_init(c, &dent_key, dir->i_ino, nm);
 585         } else {
 586                 dent->ch.node_type = UBIFS_XENT_NODE;
 587                 xent_key_init(c, &dent_key, dir->i_ino, nm);
 588         }
 589
 590         key_write(c, &dent_key, dent->key);
 591         dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino);
 592         dent->type = get_dent_type(inode->i_mode);
 593         dent->nlen = cpu_to_le16(nm->len);
 594         memcpy(dent->name, nm->name, nm->len);
 595         dent->name[nm->len] = '\0';
 596         zero_dent_node_unused(dent);
 597         ubifs_prep_grp_node(c, dent, dlen, 0);
 598
 599         ino = (void *)dent + aligned_dlen;
 600         pack_inode(c, ino, inode, 0);
 601         ino = (void *)ino + aligned_ilen;
 602         pack_inode(c, ino, dir, 1);
 603
 604         if (last_reference) {
 605                 err = ubifs_add_orphan(c, inode->i_ino);
 606                 if (err) {
 607                         release_head(c, BASEHD);
 608                         goto out_finish;
 609                 }
 610                 ui->del_cmtno = c->cmt_no;
 611         }
 612
 613         err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
 614         if (err)
 615                 goto out_release;
 616         if (!sync) {
 617                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
 618
 619                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
 620                 ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
 621         }
 622         release_head(c, BASEHD);
 623         kfree(dent);
 624
 625         if (deletion) {
 626                 err = ubifs_tnc_remove_nm(c, &dent_key, nm);
 627                 if (err)
 628                         goto out_ro;
 629                 err = ubifs_add_dirt(c, lnum, dlen);
 630         } else
 631                 err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm);
 632         if (err)
 633                 goto out_ro;
 634
 635         /*
 636          * Note, we do not remove the inode from TNC even if the last reference
 637          * to it has just been deleted, because the inode may still be opened.
 638          * Instead, the inode has been added to orphan lists and the orphan
 639          * subsystem will take further care about it.
 640          */
 641         ino_key_init(c, &ino_key, inode->i_ino);
 642         ino_offs = dent_offs + aligned_dlen;
 643         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
 644         if (err)
 645                 goto out_ro;
 646
 647         ino_key_init(c, &ino_key, dir->i_ino);
 648         ino_offs += aligned_ilen;
 649         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ);
 650         if (err)
 651                 goto out_ro;
 652
 653         finish_reservation(c);
 654         spin_lock(&ui->ui_lock);
 655         ui->synced_i_size = ui->ui_size;
 656         spin_unlock(&ui->ui_lock);
 657         mark_inode_clean(c, ui);
 658         mark_inode_clean(c, dir_ui);
 659         return 0;
 660
 661 out_finish:
 662         finish_reservation(c);
 663 out_free:
 664         kfree(dent);
 665         return err;
 666
 667 out_release:
 668         release_head(c, BASEHD);
 669 out_ro:
 670         ubifs_ro_mode(c, err);
 671         if (last_reference)
 672                 ubifs_delete_orphan(c, inode->i_ino);
 673         finish_reservation(c);
 674         return err;
 675 }
 676
 677 /**
 678  * ubifs_jnl_write_data - write a data node to the journal.
 679  * @c: UBIFS file-system description object
 680  * @inode: inode the data node belongs to
 681  * @key: node key
 682  * @buf: buffer to write
 683  * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
 684  *
 685  * This function writes a data node to the journal. Returns %0 if the data node
 686  * was successfully written, and a negative error code in case of failure.
 687  */
 688 int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
 689                          const union ubifs_key *key, const void *buf, int len)
 690 {
 691         struct ubifs_data_node *data;
 692         int err, lnum, offs, compr_type, out_len;
 693         int dlen = UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR;
 694         struct ubifs_inode *ui = ubifs_inode(inode);
 695
 696         dbg_jnl("ino %lu, blk %u, len %d, key %s",
 697                 (unsigned long)key_inum(c, key), key_block(c, key), len,
 698                 DBGKEY(key));
 699         ubifs_assert(len <= UBIFS_BLOCK_SIZE);
 700
 701         data = kmalloc(dlen, GFP_NOFS);
 702         if (!data)
 703                 return -ENOMEM;
 704
 705         data->ch.node_type = UBIFS_DATA_NODE;
 706         key_write(c, key, &data->key);
 707         data->size = cpu_to_le32(len);
 708         zero_data_node_unused(data);
 709
 710         if (!(ui->flags & UBIFS_COMPR_FL))
 711                 /* Compression is disabled for this inode */
 712                 compr_type = UBIFS_COMPR_NONE;
 713         else
 714                 compr_type = ui->compr_type;
 715
 716         out_len = dlen - UBIFS_DATA_NODE_SZ;
 717         ubifs_compress(buf, len, &data->data, &out_len, &compr_type);
 718         ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
 719
 720         dlen = UBIFS_DATA_NODE_SZ + out_len;
 721         data->compr_type = cpu_to_le16(compr_type);
 722
 723         /* Make reservation before allocating sequence numbers */
 724         err = make_reservation(c, DATAHD, dlen);
 725         if (err)
 726                 goto out_free;
 727
 728         err = write_node(c, DATAHD, data, dlen, &lnum, &offs);
 729         if (err)
 730                 goto out_release;
 731         ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
 732         release_head(c, DATAHD);
 733
 734         err = ubifs_tnc_add(c, key, lnum, offs, dlen);
 735         if (err)
 736                 goto out_ro;
 737
 738         finish_reservation(c);
 739         kfree(data);
 740         return 0;
 741
 742 out_release:
 743         release_head(c, DATAHD);
 744 out_ro:
 745         ubifs_ro_mode(c, err);
 746         finish_reservation(c);
 747 out_free:
 748         kfree(data);
 749         return err;
 750 }
 751
 752 /**
 753  * ubifs_jnl_write_inode - flush inode to the journal.
 754  * @c: UBIFS file-system description object
 755  * @inode: inode to flush
 756  *
 757  * This function writes inode @inode to the journal. If the inode is
 758  * synchronous, it also synchronizes the write-buffer. Returns zero in case of
 759  * success and a negative error code in case of failure.
 760  */
 761 int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode)
 762 {
 763         int err, lnum, offs;
 764         struct ubifs_ino_node *ino;
 765         struct ubifs_inode *ui = ubifs_inode(inode);
 766         int sync = 0, len = UBIFS_INO_NODE_SZ, last_reference = !inode->i_nlink;
 767
 768         dbg_jnl("ino %lu, nlink %u", inode->i_ino, inode->i_nlink);
 769
 770         /*
 771          * If the inode is being deleted, do not write the attached data. No
 772          * need to synchronize the write-buffer either.
 773          */
 774         if (!last_reference) {
 775                 len += ui->data_len;
 776                 sync = IS_SYNC(inode);
 777         }
 778         ino = kmalloc(len, GFP_NOFS);
 779         if (!ino)
 780                 return -ENOMEM;
 781
 782         /* Make reservation before allocating sequence numbers */
 783         err = make_reservation(c, BASEHD, len);
 784         if (err)
 785                 goto out_free;
 786
 787         pack_inode(c, ino, inode, 1);
 788         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
 789         if (err)
 790                 goto out_release;
 791         if (!sync)
 792                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
 793                                           inode->i_ino);
 794         release_head(c, BASEHD);
 795
 796         if (last_reference) {
 797                 err = ubifs_tnc_remove_ino(c, inode->i_ino);
 798                 if (err)
 799                         goto out_ro;
 800                 ubifs_delete_orphan(c, inode->i_ino);
 801                 err = ubifs_add_dirt(c, lnum, len);
 802         } else {
 803                 union ubifs_key key;
 804
 805                 ino_key_init(c, &key, inode->i_ino);
 806                 err = ubifs_tnc_add(c, &key, lnum, offs, len);
 807         }
 808         if (err)
 809                 goto out_ro;
 810
 811         finish_reservation(c);
 812         spin_lock(&ui->ui_lock);
 813         ui->synced_i_size = ui->ui_size;
 814         spin_unlock(&ui->ui_lock);
 815         kfree(ino);
 816         return 0;
 817
 818 out_release:
 819         release_head(c, BASEHD);
 820 out_ro:
 821         ubifs_ro_mode(c, err);
 822         finish_reservation(c);
 823 out_free:
 824         kfree(ino);
 825         return err;
 826 }
 827
 828 /**
 829  * ubifs_jnl_delete_inode - delete an inode.
 830  * @c: UBIFS file-system description object
 831  * @inode: inode to delete
 832  *
 833  * This function deletes inode @inode which includes removing it from orphans,
 834  * deleting it from TNC and, in some cases, writing a deletion inode to the
 835  * journal.
 836  *
 837  * When regular file inodes are unlinked or a directory inode is removed, the
 838  * 'ubifs_jnl_update()' function writes a corresponding deletion inode and
 839  * direntry to the media, and adds the inode to orphans. After this, when the
 840  * last reference to this inode has been dropped, this function is called. In
 841  * general, it has to write one more deletion inode to the media, because if
 842  * a commit happened between 'ubifs_jnl_update()' and
 843  * 'ubifs_jnl_delete_inode()', the deletion inode is not in the journal
 844  * anymore, and in fact it might not be on the flash anymore, because it might
 845  * have been garbage-collected already. And for optimization reasons UBIFS does
 846  * not read the orphan area if it has been unmounted cleanly, so it would have
 847  * no indication in the journal that there is a deleted inode which has to be
 848  * removed from TNC.
 849  *
 850  * However, if there was no commit between 'ubifs_jnl_update()' and
 851  * 'ubifs_jnl_delete_inode()', then there is no need to write the deletion
 852  * inode to the media for the second time. And this is quite a typical case.
 853  *
 854  * This function returns zero in case of success and a negative error code in
 855  * case of failure.
 856  */
 857 int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode)
 858 {
 859         int err;
 860         struct ubifs_inode *ui = ubifs_inode(inode);
 861
 862         ubifs_assert(inode->i_nlink == 0);
 863
 864         if (ui->del_cmtno != c->cmt_no)
 865                 /* A commit happened for sure */
 866                 return ubifs_jnl_write_inode(c, inode);
 867
 868         down_read(&c->commit_sem);
 869         /*
 870          * Check commit number again, because the first test has been done
 871          * without @c->commit_sem, so a commit might have happened.
 872          */
 873         if (ui->del_cmtno != c->cmt_no) {
 874                 up_read(&c->commit_sem);
 875                 return ubifs_jnl_write_inode(c, inode);
 876         }
 877
 878         err = ubifs_tnc_remove_ino(c, inode->i_ino);
 879         if (err)
 880                 ubifs_ro_mode(c, err);
 881         else
 882                 ubifs_delete_orphan(c, inode->i_ino);
 883         up_read(&c->commit_sem);
 884         return err;
 885 }
 886
 887 /**
 888  * ubifs_jnl_rename - rename a directory entry.
 889  * @c: UBIFS file-system description object
 890  * @old_dir: parent inode of directory entry to rename
 891  * @old_dentry: directory entry to rename
 892  * @new_dir: parent inode of directory entry to rename
 893  * @new_dentry: new directory entry (or directory entry to replace)
 894  * @sync: non-zero if the write-buffer has to be synchronized
 895  *
 896  * This function implements the re-name operation which may involve writing up
 897  * to 3 inodes and 2 directory entries. It marks the written inodes as clean
 898  * and returns zero on success. In case of failure, a negative error code is
 899  * returned.
 900  */
 901 int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
 902                      const struct dentry *old_dentry,
 903                      const struct inode *new_dir,
 904                      const struct dentry *new_dentry, int sync)
 905 {
 906         void *p;
 907         union ubifs_key key;
 908         struct ubifs_dent_node *dent, *dent2;
 909         int err, dlen1, dlen2, ilen, lnum, offs, len;
 910         const struct inode *old_inode = old_dentry->d_inode;
 911         const struct inode *new_inode = new_dentry->d_inode;
 912         int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
 913         int last_reference = !!(new_inode && new_inode->i_nlink == 0);
 914         int move = (old_dir != new_dir);
 915         struct ubifs_inode *uninitialized_var(new_ui);
 916
 917         dbg_jnl("dent '%.*s' in dir ino %lu to dent '%.*s' in dir ino %lu",
 918                 old_dentry->d_name.len, old_dentry->d_name.name,
 919                 old_dir->i_ino, new_dentry->d_name.len,
 920                 new_dentry->d_name.name, new_dir->i_ino);
 921         ubifs_assert(ubifs_inode(old_dir)->data_len == 0);
 922         ubifs_assert(ubifs_inode(new_dir)->data_len == 0);
 923         ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
 924         ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
 925
 926         dlen1 = UBIFS_DENT_NODE_SZ + new_dentry->d_name.len + 1;
 927         dlen2 = UBIFS_DENT_NODE_SZ + old_dentry->d_name.len + 1;
 928         if (new_inode) {
 929                 new_ui = ubifs_inode(new_inode);
 930                 ubifs_assert(mutex_is_locked(&new_ui->ui_mutex));
 931                 ilen = UBIFS_INO_NODE_SZ;
 932                 if (!last_reference)
 933                         ilen += new_ui->data_len;
 934         } else
 935                 ilen = 0;
 936
 937         aligned_dlen1 = ALIGN(dlen1, 8);
 938         aligned_dlen2 = ALIGN(dlen2, 8);
 939         len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8);
 940         if (old_dir != new_dir)
 941                 len += plen;
 942         dent = kmalloc(len, GFP_NOFS);
 943         if (!dent)
 944                 return -ENOMEM;
 945
 946         /* Make reservation before allocating sequence numbers */
 947         err = make_reservation(c, BASEHD, len);
 948         if (err)
 949                 goto out_free;
 950
 951         /* Make new dent */
 952         dent->ch.node_type = UBIFS_DENT_NODE;
 953         dent_key_init_flash(c, &dent->key, new_dir->i_ino, &new_dentry->d_name);
 954         dent->inum = cpu_to_le64(old_inode->i_ino);
 955         dent->type = get_dent_type(old_inode->i_mode);
 956         dent->nlen = cpu_to_le16(new_dentry->d_name.len);
 957         memcpy(dent->name, new_dentry->d_name.name, new_dentry->d_name.len);
 958         dent->name[new_dentry->d_name.len] = '\0';
 959         zero_dent_node_unused(dent);
 960         ubifs_prep_grp_node(c, dent, dlen1, 0);
 961
 962         /* Make deletion dent */
 963         dent2 = (void *)dent + aligned_dlen1;
 964         dent2->ch.node_type = UBIFS_DENT_NODE;
 965         dent_key_init_flash(c, &dent2->key, old_dir->i_ino,
 966                             &old_dentry->d_name);
 967         dent2->inum = 0;
 968         dent2->type = DT_UNKNOWN;
 969         dent2->nlen = cpu_to_le16(old_dentry->d_name.len);
 970         memcpy(dent2->name, old_dentry->d_name.name, old_dentry->d_name.len);
 971         dent2->name[old_dentry->d_name.len] = '\0';
 972         zero_dent_node_unused(dent2);
 973         ubifs_prep_grp_node(c, dent2, dlen2, 0);
 974
 975         p = (void *)dent2 + aligned_dlen2;
 976         if (new_inode) {
 977                 pack_inode(c, p, new_inode, 0);
 978                 p += ALIGN(ilen, 8);
 979         }
 980
 981         if (!move)
 982                 pack_inode(c, p, old_dir, 1);
 983         else {
 984                 pack_inode(c, p, old_dir, 0);
 985                 p += ALIGN(plen, 8);
 986                 pack_inode(c, p, new_dir, 1);
 987         }
 988
 989         if (last_reference) {
 990                 err = ubifs_add_orphan(c, new_inode->i_ino);
 991                 if (err) {
 992                         release_head(c, BASEHD);
 993                         goto out_finish;
 994                 }
 995                 new_ui->del_cmtno = c->cmt_no;
 996         }
 997
 998         err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
 999         if (err)
1000                 goto out_release;
1001         if (!sync) {
1002                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1003
1004                 ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
1005                 ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
1006                 if (new_inode)
1007                         ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
1008                                                   new_inode->i_ino);
1009         }
1010         release_head(c, BASEHD);
1011
1012         dent_key_init(c, &key, new_dir->i_ino, &new_dentry->d_name);
1013         err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &new_dentry->d_name);
1014         if (err)
1015                 goto out_ro;
1016
1017         err = ubifs_add_dirt(c, lnum, dlen2);
1018         if (err)
1019                 goto out_ro;
1020
1021         dent_key_init(c, &key, old_dir->i_ino, &old_dentry->d_name);
1022         err = ubifs_tnc_remove_nm(c, &key, &old_dentry->d_name);
1023         if (err)
1024                 goto out_ro;
1025
1026         offs += aligned_dlen1 + aligned_dlen2;
1027         if (new_inode) {
1028                 ino_key_init(c, &key, new_inode->i_ino);
1029                 err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
1030                 if (err)
1031                         goto out_ro;
1032                 offs += ALIGN(ilen, 8);
1033         }
1034
1035         ino_key_init(c, &key, old_dir->i_ino);
1036         err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1037         if (err)
1038                 goto out_ro;
1039
1040         if (old_dir != new_dir) {
1041                 offs += ALIGN(plen, 8);
1042                 ino_key_init(c, &key, new_dir->i_ino);
1043                 err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1044                 if (err)
1045                         goto out_ro;
1046         }
1047
1048         finish_reservation(c);
1049         if (new_inode) {
1050                 mark_inode_clean(c, new_ui);
1051                 spin_lock(&new_ui->ui_lock);
1052                 new_ui->synced_i_size = new_ui->ui_size;
1053                 spin_unlock(&new_ui->ui_lock);
1054         }
1055         mark_inode_clean(c, ubifs_inode(old_dir));
1056         if (move)
1057                 mark_inode_clean(c, ubifs_inode(new_dir));
1058         kfree(dent);
1059         return 0;
1060
1061 out_release:
1062         release_head(c, BASEHD);
1063 out_ro:
1064         ubifs_ro_mode(c, err);
1065         if (last_reference)
1066                 ubifs_delete_orphan(c, new_inode->i_ino);
1067 out_finish:
1068         finish_reservation(c);
1069 out_free:
1070         kfree(dent);
1071         return err;
1072 }
1073
1074 /**
1075  * recomp_data_node - re-compress a truncated data node.
1076  * @dn: data node to re-compress
1077  * @new_len: new length
1078  *
1079  * This function is used when an inode is truncated and the last data node of
1080  * the inode has to be re-compressed and re-written.
1081  */
1082 static int recomp_data_node(struct ubifs_data_node *dn, int *new_len)
1083 {
1084         void *buf;
1085         int err, len, compr_type, out_len;
1086
1087         out_len = le32_to_cpu(dn->size);
1088         buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
1089         if (!buf)
1090                 return -ENOMEM;
1091
1092         len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
1093         compr_type = le16_to_cpu(dn->compr_type);
1094         err = ubifs_decompress(&dn->data, len, buf, &out_len, compr_type);
1095         if (err)
1096                 goto out;
1097
1098         ubifs_compress(buf, *new_len, &dn->data, &out_len, &compr_type);
1099         ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
1100         dn->compr_type = cpu_to_le16(compr_type);
1101         dn->size = cpu_to_le32(*new_len);
1102         *new_len = UBIFS_DATA_NODE_SZ + out_len;
1103 out:
1104         kfree(buf);
1105         return err;
1106 }
1107
1108 /**
1109  * ubifs_jnl_truncate - update the journal for a truncation.
1110  * @c: UBIFS file-system description object
1111  * @inode: inode to truncate
1112  * @old_size: old size
1113  * @new_size: new size
1114  *
1115  * When the size of a file decreases due to truncation, a truncation node is
1116  * written, the journal tree is updated, and the last data block is re-written
1117  * if it has been affected. The inode is also updated in order to synchronize
1118  * the new inode size.
1119  *
1120  * This function marks the inode as clean and returns zero on success. In case
1121  * of failure, a negative error code is returned.
1122  */
1123 int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1124                        loff_t old_size, loff_t new_size)
1125 {
1126         union ubifs_key key, to_key;
1127         struct ubifs_ino_node *ino;
1128         struct ubifs_trun_node *trun;
1129         struct ubifs_data_node *uninitialized_var(dn);
1130         int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
1131         struct ubifs_inode *ui = ubifs_inode(inode);
1132         ino_t inum = inode->i_ino;
1133         unsigned int blk;
1134
1135         dbg_jnl("ino %lu, size %lld -> %lld",
1136                 (unsigned long)inum, old_size, new_size);
1137         ubifs_assert(!ui->data_len);
1138         ubifs_assert(S_ISREG(inode->i_mode));
1139         ubifs_assert(mutex_is_locked(&ui->ui_mutex));
1140
1141         sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
1142              UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
1143         ino = kmalloc(sz, GFP_NOFS);
1144         if (!ino)
1145                 return -ENOMEM;
1146
1147         trun = (void *)ino + UBIFS_INO_NODE_SZ;
1148         trun->ch.node_type = UBIFS_TRUN_NODE;
1149         trun->inum = cpu_to_le32(inum);
1150         trun->old_size = cpu_to_le64(old_size);
1151         trun->new_size = cpu_to_le64(new_size);
1152         zero_trun_node_unused(trun);
1153
1154         dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
1155         if (dlen) {
1156                 /* Get last data block so it can be truncated */
1157                 dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
1158                 blk = new_size >> UBIFS_BLOCK_SHIFT;
1159                 data_key_init(c, &key, inum, blk);
1160                 dbg_jnl("last block key %s", DBGKEY(&key));
1161                 err = ubifs_tnc_lookup(c, &key, dn);
1162                 if (err == -ENOENT)
1163                         dlen = 0; /* Not found (so it is a hole) */
1164                 else if (err)
1165                         goto out_free;
1166                 else {
1167                         if (le32_to_cpu(dn->size) <= dlen)
1168                                 dlen = 0; /* Nothing to do */
1169                         else {
1170                                 int compr_type = le16_to_cpu(dn->compr_type);
1171
1172                                 if (compr_type != UBIFS_COMPR_NONE) {
1173                                         err = recomp_data_node(dn, &dlen);
1174                                         if (err)
1175                                                 goto out_free;
1176                                 } else {
1177                                         dn->size = cpu_to_le32(dlen);
1178                                         dlen += UBIFS_DATA_NODE_SZ;
1179                                 }
1180                                 zero_data_node_unused(dn);
1181                         }
1182                 }
1183         }
1184
1185         /* Must make reservation before allocating sequence numbers */
1186         len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
1187         if (dlen)
1188                 len += dlen;
1189         err = make_reservation(c, BASEHD, len);
1190         if (err)
1191                 goto out_free;
1192
1193         pack_inode(c, ino, inode, 0);
1194         ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
1195         if (dlen)
1196                 ubifs_prep_grp_node(c, dn, dlen, 1);
1197
1198         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
1199         if (err)
1200                 goto out_release;
1201         if (!sync)
1202                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
1203         release_head(c, BASEHD);
1204
1205         if (dlen) {
1206                 sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
1207                 err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
1208                 if (err)
1209                         goto out_ro;
1210         }
1211
1212         ino_key_init(c, &key, inum);
1213         err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
1214         if (err)
1215                 goto out_ro;
1216
1217         err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
1218         if (err)
1219                 goto out_ro;
1220
1221         bit = new_size & (UBIFS_BLOCK_SIZE - 1);
1222         blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
1223         data_key_init(c, &key, inum, blk);
1224
1225         bit = old_size & (UBIFS_BLOCK_SIZE - 1);
1226         blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0 : 1);
1227         data_key_init(c, &to_key, inum, blk);
1228
1229         err = ubifs_tnc_remove_range(c, &key, &to_key);
1230         if (err)
1231                 goto out_ro;
1232
1233         finish_reservation(c);
1234         spin_lock(&ui->ui_lock);
1235         ui->synced_i_size = ui->ui_size;
1236         spin_unlock(&ui->ui_lock);
1237         mark_inode_clean(c, ui);
1238         kfree(ino);
1239         return 0;
1240
1241 out_release:
1242         release_head(c, BASEHD);
1243 out_ro:
1244         ubifs_ro_mode(c, err);
1245         finish_reservation(c);
1246 out_free:
1247         kfree(ino);
1248         return err;
1249 }
1250
1251 #ifdef CONFIG_UBIFS_FS_XATTR
1252
1253 /**
1254  * ubifs_jnl_delete_xattr - delete an extended attribute.
1255  * @c: UBIFS file-system description object
1256  * @host: host inode
1257  * @inode: extended attribute inode
1258  * @nm: extended attribute entry name
1259  *
1260  * This function delete an extended attribute which is very similar to
1261  * un-linking regular files - it writes a deletion xentry, a deletion inode and
1262  * updates the target inode. Returns zero in case of success and a negative
1263  * error code in case of failure.
1264  */
1265 int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1266                            const struct inode *inode, const struct qstr *nm)
1267 {
1268         int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
1269         struct ubifs_dent_node *xent;
1270         struct ubifs_ino_node *ino;
1271         union ubifs_key xent_key, key1, key2;
1272         int sync = IS_DIRSYNC(host);
1273         struct ubifs_inode *host_ui = ubifs_inode(host);
1274
1275         dbg_jnl("host %lu, xattr ino %lu, name '%s', data len %d",
1276                 host->i_ino, inode->i_ino, nm->name,
1277                 ubifs_inode(inode)->data_len);
1278         ubifs_assert(inode->i_nlink == 0);
1279         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1280
1281         /*
1282          * Since we are deleting the inode, we do not bother to attach any data
1283          * to it and assume its length is %UBIFS_INO_NODE_SZ.
1284          */
1285         xlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
1286         aligned_xlen = ALIGN(xlen, 8);
1287         hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
1288         len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
1289
1290         xent = kmalloc(len, GFP_NOFS);
1291         if (!xent)
1292                 return -ENOMEM;
1293
1294         /* Make reservation before allocating sequence numbers */
1295         err = make_reservation(c, BASEHD, len);
1296         if (err) {
1297                 kfree(xent);
1298                 return err;
1299         }
1300
1301         xent->ch.node_type = UBIFS_XENT_NODE;
1302         xent_key_init(c, &xent_key, host->i_ino, nm);
1303         key_write(c, &xent_key, xent->key);
1304         xent->inum = 0;
1305         xent->type = get_dent_type(inode->i_mode);
1306         xent->nlen = cpu_to_le16(nm->len);
1307         memcpy(xent->name, nm->name, nm->len);
1308         xent->name[nm->len] = '\0';
1309         zero_dent_node_unused(xent);
1310         ubifs_prep_grp_node(c, xent, xlen, 0);
1311
1312         ino = (void *)xent + aligned_xlen;
1313         pack_inode(c, ino, inode, 0);
1314         ino = (void *)ino + UBIFS_INO_NODE_SZ;
1315         pack_inode(c, ino, host, 1);
1316
1317         err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
1318         if (!sync && !err)
1319                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
1320         release_head(c, BASEHD);
1321         kfree(xent);
1322         if (err)
1323                 goto out_ro;
1324
1325         /* Remove the extended attribute entry from TNC */
1326         err = ubifs_tnc_remove_nm(c, &xent_key, nm);
1327         if (err)
1328                 goto out_ro;
1329         err = ubifs_add_dirt(c, lnum, xlen);
1330         if (err)
1331                 goto out_ro;
1332
1333         /*
1334          * Remove all nodes belonging to the extended attribute inode from TNC.
1335          * Well, there actually must be only one node - the inode itself.
1336          */
1337         lowest_ino_key(c, &key1, inode->i_ino);
1338         highest_ino_key(c, &key2, inode->i_ino);
1339         err = ubifs_tnc_remove_range(c, &key1, &key2);
1340         if (err)
1341                 goto out_ro;
1342         err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
1343         if (err)
1344                 goto out_ro;
1345
1346         /* And update TNC with the new host inode position */
1347         ino_key_init(c, &key1, host->i_ino);
1348         err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
1349         if (err)
1350                 goto out_ro;
1351
1352         finish_reservation(c);
1353         spin_lock(&host_ui->ui_lock);
1354         host_ui->synced_i_size = host_ui->ui_size;
1355         spin_unlock(&host_ui->ui_lock);
1356         mark_inode_clean(c, host_ui);
1357         return 0;
1358
1359 out_ro:
1360         ubifs_ro_mode(c, err);
1361         finish_reservation(c);
1362         return err;
1363 }
1364
1365 /**
1366  * ubifs_jnl_change_xattr - change an extended attribute.
1367  * @c: UBIFS file-system description object
1368  * @inode: extended attribute inode
1369  * @host: host inode
1370  *
1371  * This function writes the updated version of an extended attribute inode and
1372  * the host inode to the journal (to the base head). The host inode is written
1373  * after the extended attribute inode in order to guarantee that the extended
1374  * attribute will be flushed when the inode is synchronized by 'fsync()' and
1375  * consequently, the write-buffer is synchronized. This function returns zero
1376  * in case of success and a negative error code in case of failure.
1377  */
1378 int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
1379                            const struct inode *host)
1380 {
1381         int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
1382         struct ubifs_inode *host_ui = ubifs_inode(host);
1383         struct ubifs_ino_node *ino;
1384         union ubifs_key key;
1385         int sync = IS_DIRSYNC(host);
1386
1387         dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
1388         ubifs_assert(host->i_nlink > 0);
1389         ubifs_assert(inode->i_nlink > 0);
1390         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1391
1392         len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
1393         len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
1394         aligned_len1 = ALIGN(len1, 8);
1395         aligned_len = aligned_len1 + ALIGN(len2, 8);
1396
1397         ino = kmalloc(aligned_len, GFP_NOFS);
1398         if (!ino)
1399                 return -ENOMEM;
1400
1401         /* Make reservation before allocating sequence numbers */
1402         err = make_reservation(c, BASEHD, aligned_len);
1403         if (err)
1404                 goto out_free;
1405
1406         pack_inode(c, ino, host, 0);
1407         pack_inode(c, (void *)ino + aligned_len1, inode, 1);
1408
1409         err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
1410         if (!sync && !err) {
1411                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1412
1413                 ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
1414                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
1415         }
1416         release_head(c, BASEHD);
1417         if (err)
1418                 goto out_ro;
1419
1420         ino_key_init(c, &key, host->i_ino);
1421         err = ubifs_tnc_add(c, &key, lnum, offs, len1);
1422         if (err)
1423                 goto out_ro;
1424
1425         ino_key_init(c, &key, inode->i_ino);
1426         err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
1427         if (err)
1428                 goto out_ro;
1429
1430         finish_reservation(c);
1431         spin_lock(&host_ui->ui_lock);
1432         host_ui->synced_i_size = host_ui->ui_size;
1433         spin_unlock(&host_ui->ui_lock);
1434         mark_inode_clean(c, host_ui);
1435         kfree(ino);
1436         return 0;
1437
1438 out_ro:
1439         ubifs_ro_mode(c, err);
1440         finish_reservation(c);
1441 out_free:
1442         kfree(ino);
1443         return err;
1444 }
1445
1446 #endif /* CONFIG_UBIFS_FS_XATTR */