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 }
  82
  83 /**
  84  * zero_trun_node_unused - zero out unused fields of an on-flash truncation
  85  *                         node.
  86  * @trun: the truncation node to zero out
  87  */
  88 static inline void zero_trun_node_unused(struct ubifs_trun_node *trun)
  89 {
  90         memset(trun->padding, 0, 12);
  91 }
  92
  93 /**
  94  * reserve_space - reserve space in the journal.
  95  * @c: UBIFS file-system description object
  96  * @jhead: journal head number
  97  * @len: node length
  98  *
  99  * This function reserves space in journal head @head. If the reservation
 100  * succeeded, the journal head stays locked and later has to be unlocked using
 101  * 'release_head()'. 'write_node()' and 'write_head()' functions also unlock
 102  * it. Returns zero in case of success, %-EAGAIN if commit has to be done, and
 103  * other negative error codes in case of other failures.
 104  */
 105 static int reserve_space(struct ubifs_info *c, int jhead, int len)
 106 {
 107         int err = 0, err1, retries = 0, avail, lnum, offs, squeeze;
 108         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 109
 110         /*
 111          * Typically, the base head has smaller nodes written to it, so it is
 112          * better to try to allocate space at the ends of eraseblocks. This is
 113          * what the squeeze parameter does.
 114          */
 115         ubifs_assert(!c->ro_media && !c->ro_mount);
 116         squeeze = (jhead == BASEHD);
 117 again:
 118         mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 119
 120         if (c->ro_error) {
 121                 err = -EROFS;
 122                 goto out_unlock;
 123         }
 124
 125         avail = c->leb_size - wbuf->offs - wbuf->used;
 126         if (wbuf->lnum != -1 && avail >= len)
 127                 return 0;
 128
 129         /*
 130          * Write buffer wasn't seek'ed or there is no enough space - look for an
 131          * LEB with some empty space.
 132          */
 133         lnum = ubifs_find_free_space(c, len, &offs, squeeze);
 134         if (lnum >= 0)
 135                 goto out;
 136
 137         err = lnum;
 138         if (err != -ENOSPC)
 139                 goto out_unlock;
 140
 141         /*
 142          * No free space, we have to run garbage collector to make
 143          * some. But the write-buffer mutex has to be unlocked because
 144          * GC also takes it.
 145          */
 146         dbg_jnl("no free space in jhead %s, run GC", dbg_jhead(jhead));
 147         mutex_unlock(&wbuf->io_mutex);
 148
 149         lnum = ubifs_garbage_collect(c, 0);
 150         if (lnum < 0) {
 151                 err = lnum;
 152                 if (err != -ENOSPC)
 153                         return err;
 154
 155                 /*
 156                  * GC could not make a free LEB. But someone else may
 157                  * have allocated new bud for this journal head,
 158                  * because we dropped @wbuf->io_mutex, so try once
 159                  * again.
 160                  */
 161                 dbg_jnl("GC couldn't make a free LEB for jhead %s",
 162                         dbg_jhead(jhead));
 163                 if (retries++ < 2) {
 164                         dbg_jnl("retry (%d)", retries);
 165                         goto again;
 166                 }
 167
 168                 dbg_jnl("return -ENOSPC");
 169                 return err;
 170         }
 171
 172         mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 173         dbg_jnl("got LEB %d for jhead %s", lnum, dbg_jhead(jhead));
 174         avail = c->leb_size - wbuf->offs - wbuf->used;
 175
 176         if (wbuf->lnum != -1 && avail >= len) {
 177                 /*
 178                  * Someone else has switched the journal head and we have
 179                  * enough space now. This happens when more than one process is
 180                  * trying to write to the same journal head at the same time.
 181                  */
 182                 dbg_jnl("return LEB %d back, already have LEB %d:%d",
 183                         lnum, wbuf->lnum, wbuf->offs + wbuf->used);
 184                 err = ubifs_return_leb(c, lnum);
 185                 if (err)
 186                         goto out_unlock;
 187                 return 0;
 188         }
 189
 190         offs = 0;
 191
 192 out:
 193         /*
 194          * Make sure we synchronize the write-buffer before we add the new bud
 195          * to the log. Otherwise we may have a power cut after the log
 196          * reference node for the last bud (@lnum) is written but before the
 197          * write-buffer data are written to the next-to-last bud
 198          * (@wbuf->lnum). And the effect would be that the recovery would see
 199          * that there is corruption in the next-to-last bud.
 200          */
 201         err = ubifs_wbuf_sync_nolock(wbuf);
 202         if (err)
 203                 goto out_return;
 204         err = ubifs_add_bud_to_log(c, jhead, lnum, offs);
 205         if (err)
 206                 goto out_return;
 207         err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs);
 208         if (err)
 209                 goto out_unlock;
 210
 211         return 0;
 212
 213 out_unlock:
 214         mutex_unlock(&wbuf->io_mutex);
 215         return err;
 216
 217 out_return:
 218         /* An error occurred and the LEB has to be returned to lprops */
 219         ubifs_assert(err < 0);
 220         err1 = ubifs_return_leb(c, lnum);
 221         if (err1 && err == -EAGAIN)
 222                 /*
 223                  * Return original error code only if it is not %-EAGAIN,
 224                  * which is not really an error. Otherwise, return the error
 225                  * code of 'ubifs_return_leb()'.
 226                  */
 227                 err = err1;
 228         mutex_unlock(&wbuf->io_mutex);
 229         return err;
 230 }
 231
 232 /**
 233  * write_node - write node to a journal head.
 234  * @c: UBIFS file-system description object
 235  * @jhead: journal head
 236  * @node: node to write
 237  * @len: node length
 238  * @lnum: LEB number written is returned here
 239  * @offs: offset written is returned here
 240  *
 241  * This function writes a node to reserved space of journal head @jhead.
 242  * Returns zero in case of success and a negative error code in case of
 243  * failure.
 244  */
 245 static int write_node(struct ubifs_info *c, int jhead, void *node, int len,
 246                       int *lnum, int *offs)
 247 {
 248         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 249
 250         ubifs_assert(jhead != GCHD);
 251
 252         *lnum = c->jheads[jhead].wbuf.lnum;
 253         *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 254
 255         dbg_jnl("jhead %s, LEB %d:%d, len %d",
 256                 dbg_jhead(jhead), *lnum, *offs, len);
 257         ubifs_prepare_node(c, node, len, 0);
 258
 259         return ubifs_wbuf_write_nolock(wbuf, node, len);
 260 }
 261
 262 /**
 263  * write_head - write data to a journal head.
 264  * @c: UBIFS file-system description object
 265  * @jhead: journal head
 266  * @buf: buffer to write
 267  * @len: length to write
 268  * @lnum: LEB number written is returned here
 269  * @offs: offset written is returned here
 270  * @sync: non-zero if the write-buffer has to by synchronized
 271  *
 272  * This function is the same as 'write_node()' but it does not assume the
 273  * buffer it is writing is a node, so it does not prepare it (which means
 274  * initializing common header and calculating CRC).
 275  */
 276 static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
 277                       int *lnum, int *offs, int sync)
 278 {
 279         int err;
 280         struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 281
 282         ubifs_assert(jhead != GCHD);
 283
 284         *lnum = c->jheads[jhead].wbuf.lnum;
 285         *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 286         dbg_jnl("jhead %s, LEB %d:%d, len %d",
 287                 dbg_jhead(jhead), *lnum, *offs, len);
 288
 289         err = ubifs_wbuf_write_nolock(wbuf, buf, len);
 290         if (err)
 291                 return err;
 292         if (sync)
 293                 err = ubifs_wbuf_sync_nolock(wbuf);
 294         return err;
 295 }
 296
 297 /**
 298  * make_reservation - reserve journal space.
 299  * @c: UBIFS file-system description object
 300  * @jhead: journal head
 301  * @len: how many bytes to reserve
 302  *
 303  * This function makes space reservation in journal head @jhead. The function
 304  * takes the commit lock and locks the journal head, and the caller has to
 305  * unlock the head and finish the reservation with 'finish_reservation()'.
 306  * Returns zero in case of success and a negative error code in case of
 307  * failure.
 308  *
 309  * Note, the journal head may be unlocked as soon as the data is written, while
 310  * the commit lock has to be released after the data has been added to the
 311  * TNC.
 312  */
 313 static int make_reservation(struct ubifs_info *c, int jhead, int len)
 314 {
 315         int err, cmt_retries = 0, nospc_retries = 0;
 316
 317 again:
 318         down_read(&c->commit_sem);
 319         err = reserve_space(c, jhead, len);
 320         if (!err)
 321                 return 0;
 322         up_read(&c->commit_sem);
 323
 324         if (err == -ENOSPC) {
 325                 /*
 326                  * GC could not make any progress. We should try to commit
 327                  * once because it could make some dirty space and GC would
 328                  * make progress, so make the error -EAGAIN so that the below
 329                  * will commit and re-try.
 330                  */
 331                 if (nospc_retries++ < 2) {
 332                         dbg_jnl("no space, retry");
 333                         err = -EAGAIN;
 334                 }
 335
 336                 /*
 337                  * This means that the budgeting is incorrect. We always have
 338                  * to be able to write to the media, because all operations are
 339                  * budgeted. Deletions are not budgeted, though, but we reserve
 340                  * an extra LEB for them.
 341                  */
 342         }
 343
 344         if (err != -EAGAIN)
 345                 goto out;
 346
 347         /*
 348          * -EAGAIN means that the journal is full or too large, or the above
 349          * code wants to do one commit. Do this and re-try.
 350          */
 351         if (cmt_retries > 128) {
 352                 /*
 353                  * This should not happen unless the journal size limitations
 354                  * are too tough.
 355                  */
 356                 ubifs_err(c, "stuck in space allocation");
 357                 err = -ENOSPC;
 358                 goto out;
 359         } else if (cmt_retries > 32)
 360                 ubifs_warn(c, "too many space allocation re-tries (%d)",
 361                            cmt_retries);
 362
 363         dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
 364                 cmt_retries);
 365         cmt_retries += 1;
 366
 367         err = ubifs_run_commit(c);
 368         if (err)
 369                 return err;
 370         goto again;
 371
 372 out:
 373         ubifs_err(c, "cannot reserve %d bytes in jhead %d, error %d",
 374                   len, jhead, err);
 375         if (err == -ENOSPC) {
 376                 /* This are some budgeting problems, print useful information */
 377                 down_write(&c->commit_sem);
 378                 dump_stack();
 379                 ubifs_dump_budg(c, &c->bi);
 380                 ubifs_dump_lprops(c);
 381                 cmt_retries = dbg_check_lprops(c);
 382                 up_write(&c->commit_sem);
 383         }
 384         return err;
 385 }
 386
 387 /**
 388  * release_head - release a journal head.
 389  * @c: UBIFS file-system description object
 390  * @jhead: journal head
 391  *
 392  * This function releases journal head @jhead which was locked by
 393  * the 'make_reservation()' function. It has to be called after each successful
 394  * 'make_reservation()' invocation.
 395  */
 396 static inline void release_head(struct ubifs_info *c, int jhead)
 397 {
 398         mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
 399 }
 400
 401 /**
 402  * finish_reservation - finish a reservation.
 403  * @c: UBIFS file-system description object
 404  *
 405  * This function finishes journal space reservation. It must be called after
 406  * 'make_reservation()'.
 407  */
 408 static void finish_reservation(struct ubifs_info *c)
 409 {
 410         up_read(&c->commit_sem);
 411 }
 412
 413 /**
 414  * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
 415  * @mode: inode mode
 416  */
 417 static int get_dent_type(int mode)
 418 {
 419         switch (mode & S_IFMT) {
 420         case S_IFREG:
 421                 return UBIFS_ITYPE_REG;
 422         case S_IFDIR:
 423                 return UBIFS_ITYPE_DIR;
 424         case S_IFLNK:
 425                 return UBIFS_ITYPE_LNK;
 426         case S_IFBLK:
 427                 return UBIFS_ITYPE_BLK;
 428         case S_IFCHR:
 429                 return UBIFS_ITYPE_CHR;
 430         case S_IFIFO:
 431                 return UBIFS_ITYPE_FIFO;
 432         case S_IFSOCK:
 433                 return UBIFS_ITYPE_SOCK;
 434         default:
 435                 BUG();
 436         }
 437         return 0;
 438 }
 439
 440 /**
 441  * pack_inode - pack an inode node.
 442  * @c: UBIFS file-system description object
 443  * @ino: buffer in which to pack inode node
 444  * @inode: inode to pack
 445  * @last: indicates the last node of the group
 446  */
 447 static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
 448                        const struct inode *inode, int last)
 449 {
 450         int data_len = 0, last_reference = !inode->i_nlink;
 451         struct ubifs_inode *ui = ubifs_inode(inode);
 452
 453         ino->ch.node_type = UBIFS_INO_NODE;
 454         ino_key_init_flash(c, &ino->key, inode->i_ino);
 455         ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum);
 456         ino->atime_sec  = cpu_to_le64(inode->i_atime.tv_sec);
 457         ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
 458         ino->ctime_sec  = cpu_to_le64(inode->i_ctime.tv_sec);
 459         ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 460         ino->mtime_sec  = cpu_to_le64(inode->i_mtime.tv_sec);
 461         ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 462         ino->uid   = cpu_to_le32(i_uid_read(inode));
 463         ino->gid   = cpu_to_le32(i_gid_read(inode));
 464         ino->mode  = cpu_to_le32(inode->i_mode);
 465         ino->flags = cpu_to_le32(ui->flags);
 466         ino->size  = cpu_to_le64(ui->ui_size);
 467         ino->nlink = cpu_to_le32(inode->i_nlink);
 468         ino->compr_type  = cpu_to_le16(ui->compr_type);
 469         ino->data_len    = cpu_to_le32(ui->data_len);
 470         ino->xattr_cnt   = cpu_to_le32(ui->xattr_cnt);
 471         ino->xattr_size  = cpu_to_le32(ui->xattr_size);
 472         ino->xattr_names = cpu_to_le32(ui->xattr_names);
 473         zero_ino_node_unused(ino);
 474
 475         /*
 476          * Drop the attached data if this is a deletion inode, the data is not
 477          * needed anymore.
 478          */
 479         if (!last_reference) {
 480                 memcpy(ino->data, ui->data, ui->data_len);
 481                 data_len = ui->data_len;
 482         }
 483
 484         ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last);
 485 }
 486
 487 /**
 488  * mark_inode_clean - mark UBIFS inode as clean.
 489  * @c: UBIFS file-system description object
 490  * @ui: UBIFS inode to mark as clean
 491  *
 492  * This helper function marks UBIFS inode @ui as clean by cleaning the
 493  * @ui->dirty flag and releasing its budget. Note, VFS may still treat the
 494  * inode as dirty and try to write it back, but 'ubifs_write_inode()' would
 495  * just do nothing.
 496  */
 497 static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui)
 498 {
 499         if (ui->dirty)
 500                 ubifs_release_dirty_inode_budget(c, ui);
 501         ui->dirty = 0;
 502 }
 503
 504 static void set_dent_cookie(struct ubifs_info *c, struct ubifs_dent_node *dent)
 505 {
 506         if (c->double_hash)
 507                 dent->cookie = prandom_u32();
 508         else
 509                 dent->cookie = 0;
 510 }
 511
 512 /**
 513  * ubifs_jnl_update - update inode.
 514  * @c: UBIFS file-system description object
 515  * @dir: parent inode or host inode in case of extended attributes
 516  * @nm: directory entry name
 517  * @inode: inode to update
 518  * @deletion: indicates a directory entry deletion i.e unlink or rmdir
 519  * @xent: non-zero if the directory entry is an extended attribute entry
 520  *
 521  * This function updates an inode by writing a directory entry (or extended
 522  * attribute entry), the inode itself, and the parent directory inode (or the
 523  * host inode) to the journal.
 524  *
 525  * The function writes the host inode @dir last, which is important in case of
 526  * extended attributes. Indeed, then we guarantee that if the host inode gets
 527  * synchronized (with 'fsync()'), and the write-buffer it sits in gets flushed,
 528  * the extended attribute inode gets flushed too. And this is exactly what the
 529  * user expects - synchronizing the host inode synchronizes its extended
 530  * attributes. Similarly, this guarantees that if @dir is synchronized, its
 531  * directory entry corresponding to @nm gets synchronized too.
 532  *
 533  * If the inode (@inode) or the parent directory (@dir) are synchronous, this
 534  * function synchronizes the write-buffer.
 535  *
 536  * This function marks the @dir and @inode inodes as clean and returns zero on
 537  * success. In case of failure, a negative error code is returned.
 538  */
 539 int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
 540                      const struct fscrypt_name *nm, const struct inode *inode,
 541                      int deletion, int xent)
 542 {
 543         int err, dlen, ilen, len, lnum, ino_offs, dent_offs;
 544         int aligned_dlen, aligned_ilen, sync = IS_DIRSYNC(dir);
 545         int last_reference = !!(deletion && inode->i_nlink == 0);
 546         struct ubifs_inode *ui = ubifs_inode(inode);
 547         struct ubifs_inode *host_ui = ubifs_inode(dir);
 548         struct ubifs_dent_node *dent;
 549         struct ubifs_ino_node *ino;
 550         union ubifs_key dent_key, ino_key;
 551
 552         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
 553
 554         dlen = UBIFS_DENT_NODE_SZ + fname_len(nm) + 1;
 555         ilen = UBIFS_INO_NODE_SZ;
 556
 557         /*
 558          * If the last reference to the inode is being deleted, then there is
 559          * no need to attach and write inode data, it is being deleted anyway.
 560          * And if the inode is being deleted, no need to synchronize
 561          * write-buffer even if the inode is synchronous.
 562          */
 563         if (!last_reference) {
 564                 ilen += ui->data_len;
 565                 sync |= IS_SYNC(inode);
 566         }
 567
 568         aligned_dlen = ALIGN(dlen, 8);
 569         aligned_ilen = ALIGN(ilen, 8);
 570
 571         len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ;
 572         /* Make sure to also account for extended attributes */
 573         len += host_ui->data_len;
 574
 575         dent = kzalloc(len, GFP_NOFS);
 576         if (!dent)
 577                 return -ENOMEM;
 578
 579         /* Make reservation before allocating sequence numbers */
 580         err = make_reservation(c, BASEHD, len);
 581         if (err)
 582                 goto out_free;
 583
 584         if (!xent) {
 585                 dent->ch.node_type = UBIFS_DENT_NODE;
 586                 if (nm->hash)
 587                         dent_key_init_hash(c, &dent_key, dir->i_ino, nm->hash);
 588                 else
 589                         dent_key_init(c, &dent_key, dir->i_ino, nm);
 590         } else {
 591                 dent->ch.node_type = UBIFS_XENT_NODE;
 592                 xent_key_init(c, &dent_key, dir->i_ino, nm);
 593         }
 594
 595         key_write(c, &dent_key, dent->key);
 596         dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino);
 597         dent->type = get_dent_type(inode->i_mode);
 598         dent->nlen = cpu_to_le16(fname_len(nm));
 599         memcpy(dent->name, fname_name(nm), fname_len(nm));
 600         dent->name[fname_len(nm)] = '\0';
 601         set_dent_cookie(c, dent);
 602
 603         zero_dent_node_unused(dent);
 604         ubifs_prep_grp_node(c, dent, dlen, 0);
 605
 606         ino = (void *)dent + aligned_dlen;
 607         pack_inode(c, ino, inode, 0);
 608         ino = (void *)ino + aligned_ilen;
 609         pack_inode(c, ino, dir, 1);
 610
 611         if (last_reference) {
 612                 err = ubifs_add_orphan(c, inode->i_ino);
 613                 if (err) {
 614                         release_head(c, BASEHD);
 615                         goto out_finish;
 616                 }
 617                 ui->del_cmtno = c->cmt_no;
 618         }
 619
 620         err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
 621         if (err)
 622                 goto out_release;
 623         if (!sync) {
 624                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
 625
 626                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
 627                 ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
 628         }
 629         release_head(c, BASEHD);
 630         kfree(dent);
 631
 632         if (deletion) {
 633                 if (nm->hash)
 634                         err = ubifs_tnc_remove_dh(c, &dent_key, nm->minor_hash);
 635                 else
 636                         err = ubifs_tnc_remove_nm(c, &dent_key, nm);
 637                 if (err)
 638                         goto out_ro;
 639                 err = ubifs_add_dirt(c, lnum, dlen);
 640         } else
 641                 err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm);
 642         if (err)
 643                 goto out_ro;
 644
 645         /*
 646          * Note, we do not remove the inode from TNC even if the last reference
 647          * to it has just been deleted, because the inode may still be opened.
 648          * Instead, the inode has been added to orphan lists and the orphan
 649          * subsystem will take further care about it.
 650          */
 651         ino_key_init(c, &ino_key, inode->i_ino);
 652         ino_offs = dent_offs + aligned_dlen;
 653         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
 654         if (err)
 655                 goto out_ro;
 656
 657         ino_key_init(c, &ino_key, dir->i_ino);
 658         ino_offs += aligned_ilen;
 659         err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs,
 660                             UBIFS_INO_NODE_SZ + host_ui->data_len);
 661         if (err)
 662                 goto out_ro;
 663
 664         finish_reservation(c);
 665         spin_lock(&ui->ui_lock);
 666         ui->synced_i_size = ui->ui_size;
 667         spin_unlock(&ui->ui_lock);
 668         mark_inode_clean(c, ui);
 669         mark_inode_clean(c, host_ui);
 670         return 0;
 671
 672 out_finish:
 673         finish_reservation(c);
 674 out_free:
 675         kfree(dent);
 676         return err;
 677
 678 out_release:
 679         release_head(c, BASEHD);
 680         kfree(dent);
 681 out_ro:
 682         ubifs_ro_mode(c, err);
 683         if (last_reference)
 684                 ubifs_delete_orphan(c, inode->i_ino);
 685         finish_reservation(c);
 686         return err;
 687 }
 688
 689 /**
 690  * ubifs_jnl_write_data - write a data node to the journal.
 691  * @c: UBIFS file-system description object
 692  * @inode: inode the data node belongs to
 693  * @key: node key
 694  * @buf: buffer to write
 695  * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
 696  *
 697  * This function writes a data node to the journal. Returns %0 if the data node
 698  * was successfully written, and a negative error code in case of failure.
 699  */
 700 int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
 701                          const union ubifs_key *key, const void *buf, int len)
 702 {
 703         struct ubifs_data_node *data;
 704         int err, lnum, offs, compr_type, out_len, compr_len;
 705         int dlen = COMPRESSED_DATA_NODE_BUF_SZ, allocated = 1;
 706         struct ubifs_inode *ui = ubifs_inode(inode);
 707         bool encrypted = ubifs_crypt_is_encrypted(inode);
 708
 709         dbg_jnlk(key, "ino %lu, blk %u, len %d, key ",
 710                 (unsigned long)key_inum(c, key), key_block(c, key), len);
 711         ubifs_assert(len <= UBIFS_BLOCK_SIZE);
 712
 713         if (encrypted)
 714                 dlen += UBIFS_CIPHER_BLOCK_SIZE;
 715
 716         data = kmalloc(dlen, GFP_NOFS | __GFP_NOWARN);
 717         if (!data) {
 718                 /*
 719                  * Fall-back to the write reserve buffer. Note, we might be
 720                  * currently on the memory reclaim path, when the kernel is
 721                  * trying to free some memory by writing out dirty pages. The
 722                  * write reserve buffer helps us to guarantee that we are
 723                  * always able to write the data.
 724                  */
 725                 allocated = 0;
 726                 mutex_lock(&c->write_reserve_mutex);
 727                 data = c->write_reserve_buf;
 728         }
 729
 730         data->ch.node_type = UBIFS_DATA_NODE;
 731         key_write(c, key, &data->key);
 732         data->size = cpu_to_le32(len);
 733
 734         if (!(ui->flags & UBIFS_COMPR_FL))
 735                 /* Compression is disabled for this inode */
 736                 compr_type = UBIFS_COMPR_NONE;
 737         else
 738                 compr_type = ui->compr_type;
 739
 740         out_len = compr_len = dlen - UBIFS_DATA_NODE_SZ;
 741         ubifs_compress(c, buf, len, &data->data, &compr_len, &compr_type);
 742         ubifs_assert(compr_len <= UBIFS_BLOCK_SIZE);
 743
 744         if (encrypted) {
 745                 err = ubifs_encrypt(inode, data, compr_len, &out_len, key_block(c, key));
 746                 if (err)
 747                         goto out_free;
 748
 749         } else {
 750                 data->compr_size = 0;
 751                 out_len = compr_len;
 752         }
 753
 754         dlen = UBIFS_DATA_NODE_SZ + out_len;
 755         data->compr_type = cpu_to_le16(compr_type);
 756
 757         /* Make reservation before allocating sequence numbers */
 758         err = make_reservation(c, DATAHD, dlen);
 759         if (err)
 760                 goto out_free;
 761
 762         err = write_node(c, DATAHD, data, dlen, &lnum, &offs);
 763         if (err)
 764                 goto out_release;
 765         ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
 766         release_head(c, DATAHD);
 767
 768         err = ubifs_tnc_add(c, key, lnum, offs, dlen);
 769         if (err)
 770                 goto out_ro;
 771
 772         finish_reservation(c);
 773         if (!allocated)
 774                 mutex_unlock(&c->write_reserve_mutex);
 775         else
 776                 kfree(data);
 777         return 0;
 778
 779 out_release:
 780         release_head(c, DATAHD);
 781 out_ro:
 782         ubifs_ro_mode(c, err);
 783         finish_reservation(c);
 784 out_free:
 785         if (!allocated)
 786                 mutex_unlock(&c->write_reserve_mutex);
 787         else
 788                 kfree(data);
 789         return err;
 790 }
 791
 792 /**
 793  * ubifs_jnl_write_inode - flush inode to the journal.
 794  * @c: UBIFS file-system description object
 795  * @inode: inode to flush
 796  *
 797  * This function writes inode @inode to the journal. If the inode is
 798  * synchronous, it also synchronizes the write-buffer. Returns zero in case of
 799  * success and a negative error code in case of failure.
 800  */
 801 int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode)
 802 {
 803         int err, lnum, offs;
 804         struct ubifs_ino_node *ino;
 805         struct ubifs_inode *ui = ubifs_inode(inode);
 806         int sync = 0, len = UBIFS_INO_NODE_SZ, last_reference = !inode->i_nlink;
 807
 808         dbg_jnl("ino %lu, nlink %u", inode->i_ino, inode->i_nlink);
 809
 810         /*
 811          * If the inode is being deleted, do not write the attached data. No
 812          * need to synchronize the write-buffer either.
 813          */
 814         if (!last_reference) {
 815                 len += ui->data_len;
 816                 sync = IS_SYNC(inode);
 817         }
 818         ino = kmalloc(len, GFP_NOFS);
 819         if (!ino)
 820                 return -ENOMEM;
 821
 822         /* Make reservation before allocating sequence numbers */
 823         err = make_reservation(c, BASEHD, len);
 824         if (err)
 825                 goto out_free;
 826
 827         pack_inode(c, ino, inode, 1);
 828         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
 829         if (err)
 830                 goto out_release;
 831         if (!sync)
 832                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
 833                                           inode->i_ino);
 834         release_head(c, BASEHD);
 835
 836         if (last_reference) {
 837                 err = ubifs_tnc_remove_ino(c, inode->i_ino);
 838                 if (err)
 839                         goto out_ro;
 840                 ubifs_delete_orphan(c, inode->i_ino);
 841                 err = ubifs_add_dirt(c, lnum, len);
 842         } else {
 843                 union ubifs_key key;
 844
 845                 ino_key_init(c, &key, inode->i_ino);
 846                 err = ubifs_tnc_add(c, &key, lnum, offs, len);
 847         }
 848         if (err)
 849                 goto out_ro;
 850
 851         finish_reservation(c);
 852         spin_lock(&ui->ui_lock);
 853         ui->synced_i_size = ui->ui_size;
 854         spin_unlock(&ui->ui_lock);
 855         kfree(ino);
 856         return 0;
 857
 858 out_release:
 859         release_head(c, BASEHD);
 860 out_ro:
 861         ubifs_ro_mode(c, err);
 862         finish_reservation(c);
 863 out_free:
 864         kfree(ino);
 865         return err;
 866 }
 867
 868 /**
 869  * ubifs_jnl_delete_inode - delete an inode.
 870  * @c: UBIFS file-system description object
 871  * @inode: inode to delete
 872  *
 873  * This function deletes inode @inode which includes removing it from orphans,
 874  * deleting it from TNC and, in some cases, writing a deletion inode to the
 875  * journal.
 876  *
 877  * When regular file inodes are unlinked or a directory inode is removed, the
 878  * 'ubifs_jnl_update()' function writes a corresponding deletion inode and
 879  * direntry to the media, and adds the inode to orphans. After this, when the
 880  * last reference to this inode has been dropped, this function is called. In
 881  * general, it has to write one more deletion inode to the media, because if
 882  * a commit happened between 'ubifs_jnl_update()' and
 883  * 'ubifs_jnl_delete_inode()', the deletion inode is not in the journal
 884  * anymore, and in fact it might not be on the flash anymore, because it might
 885  * have been garbage-collected already. And for optimization reasons UBIFS does
 886  * not read the orphan area if it has been unmounted cleanly, so it would have
 887  * no indication in the journal that there is a deleted inode which has to be
 888  * removed from TNC.
 889  *
 890  * However, if there was no commit between 'ubifs_jnl_update()' and
 891  * 'ubifs_jnl_delete_inode()', then there is no need to write the deletion
 892  * inode to the media for the second time. And this is quite a typical case.
 893  *
 894  * This function returns zero in case of success and a negative error code in
 895  * case of failure.
 896  */
 897 int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode)
 898 {
 899         int err;
 900         struct ubifs_inode *ui = ubifs_inode(inode);
 901
 902         ubifs_assert(inode->i_nlink == 0);
 903
 904         if (ui->del_cmtno != c->cmt_no)
 905                 /* A commit happened for sure */
 906                 return ubifs_jnl_write_inode(c, inode);
 907
 908         down_read(&c->commit_sem);
 909         /*
 910          * Check commit number again, because the first test has been done
 911          * without @c->commit_sem, so a commit might have happened.
 912          */
 913         if (ui->del_cmtno != c->cmt_no) {
 914                 up_read(&c->commit_sem);
 915                 return ubifs_jnl_write_inode(c, inode);
 916         }
 917
 918         err = ubifs_tnc_remove_ino(c, inode->i_ino);
 919         if (err)
 920                 ubifs_ro_mode(c, err);
 921         else
 922                 ubifs_delete_orphan(c, inode->i_ino);
 923         up_read(&c->commit_sem);
 924         return err;
 925 }
 926
 927 /**
 928  * ubifs_jnl_xrename - cross rename two directory entries.
 929  * @c: UBIFS file-system description object
 930  * @fst_dir: parent inode of 1st directory entry to exchange
 931  * @fst_inode: 1st inode to exchange
 932  * @fst_nm: name of 1st inode to exchange
 933  * @snd_dir: parent inode of 2nd directory entry to exchange
 934  * @snd_inode: 2nd inode to exchange
 935  * @snd_nm: name of 2nd inode to exchange
 936  * @sync: non-zero if the write-buffer has to be synchronized
 937  *
 938  * This function implements the cross rename operation which may involve
 939  * writing 2 inodes and 2 directory entries. It marks the written inodes as clean
 940  * and returns zero on success. In case of failure, a negative error code is
 941  * returned.
 942  */
 943 int ubifs_jnl_xrename(struct ubifs_info *c, const struct inode *fst_dir,
 944                       const struct inode *fst_inode,
 945                       const struct fscrypt_name *fst_nm,
 946                       const struct inode *snd_dir,
 947                       const struct inode *snd_inode,
 948                       const struct fscrypt_name *snd_nm, int sync)
 949 {
 950         union ubifs_key key;
 951         struct ubifs_dent_node *dent1, *dent2;
 952         int err, dlen1, dlen2, lnum, offs, len, plen = UBIFS_INO_NODE_SZ;
 953         int aligned_dlen1, aligned_dlen2;
 954         int twoparents = (fst_dir != snd_dir);
 955         void *p;
 956
 957         ubifs_assert(ubifs_inode(fst_dir)->data_len == 0);
 958         ubifs_assert(ubifs_inode(snd_dir)->data_len == 0);
 959         ubifs_assert(mutex_is_locked(&ubifs_inode(fst_dir)->ui_mutex));
 960         ubifs_assert(mutex_is_locked(&ubifs_inode(snd_dir)->ui_mutex));
 961
 962         dlen1 = UBIFS_DENT_NODE_SZ + fname_len(snd_nm) + 1;
 963         dlen2 = UBIFS_DENT_NODE_SZ + fname_len(fst_nm) + 1;
 964         aligned_dlen1 = ALIGN(dlen1, 8);
 965         aligned_dlen2 = ALIGN(dlen2, 8);
 966
 967         len = aligned_dlen1 + aligned_dlen2 + ALIGN(plen, 8);
 968         if (twoparents)
 969                 len += plen;
 970
 971         dent1 = kzalloc(len, GFP_NOFS);
 972         if (!dent1)
 973                 return -ENOMEM;
 974
 975         /* Make reservation before allocating sequence numbers */
 976         err = make_reservation(c, BASEHD, len);
 977         if (err)
 978                 goto out_free;
 979
 980         /* Make new dent for 1st entry */
 981         dent1->ch.node_type = UBIFS_DENT_NODE;
 982         dent_key_init_flash(c, &dent1->key, snd_dir->i_ino, snd_nm);
 983         dent1->inum = cpu_to_le64(fst_inode->i_ino);
 984         dent1->type = get_dent_type(fst_inode->i_mode);
 985         dent1->nlen = cpu_to_le16(fname_len(snd_nm));
 986         memcpy(dent1->name, fname_name(snd_nm), fname_len(snd_nm));
 987         dent1->name[fname_len(snd_nm)] = '\0';
 988         set_dent_cookie(c, dent1);
 989         zero_dent_node_unused(dent1);
 990         ubifs_prep_grp_node(c, dent1, dlen1, 0);
 991
 992         /* Make new dent for 2nd entry */
 993         dent2 = (void *)dent1 + aligned_dlen1;
 994         dent2->ch.node_type = UBIFS_DENT_NODE;
 995         dent_key_init_flash(c, &dent2->key, fst_dir->i_ino, fst_nm);
 996         dent2->inum = cpu_to_le64(snd_inode->i_ino);
 997         dent2->type = get_dent_type(snd_inode->i_mode);
 998         dent2->nlen = cpu_to_le16(fname_len(fst_nm));
 999         memcpy(dent2->name, fname_name(fst_nm), fname_len(fst_nm));
1000         dent2->name[fname_len(fst_nm)] = '\0';
1001         set_dent_cookie(c, dent2);
1002         zero_dent_node_unused(dent2);
1003         ubifs_prep_grp_node(c, dent2, dlen2, 0);
1004
1005         p = (void *)dent2 + aligned_dlen2;
1006         if (!twoparents)
1007                 pack_inode(c, p, fst_dir, 1);
1008         else {
1009                 pack_inode(c, p, fst_dir, 0);
1010                 p += ALIGN(plen, 8);
1011                 pack_inode(c, p, snd_dir, 1);
1012         }
1013
1014         err = write_head(c, BASEHD, dent1, len, &lnum, &offs, sync);
1015         if (err)
1016                 goto out_release;
1017         if (!sync) {
1018                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1019
1020                 ubifs_wbuf_add_ino_nolock(wbuf, fst_dir->i_ino);
1021                 ubifs_wbuf_add_ino_nolock(wbuf, snd_dir->i_ino);
1022         }
1023         release_head(c, BASEHD);
1024
1025         dent_key_init(c, &key, snd_dir->i_ino, snd_nm);
1026         err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, snd_nm);
1027         if (err)
1028                 goto out_ro;
1029
1030         offs += aligned_dlen1;
1031         dent_key_init(c, &key, fst_dir->i_ino, fst_nm);
1032         err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen2, fst_nm);
1033         if (err)
1034                 goto out_ro;
1035
1036         offs += aligned_dlen2;
1037
1038         ino_key_init(c, &key, fst_dir->i_ino);
1039         err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1040         if (err)
1041                 goto out_ro;
1042
1043         if (twoparents) {
1044                 offs += ALIGN(plen, 8);
1045                 ino_key_init(c, &key, snd_dir->i_ino);
1046                 err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1047                 if (err)
1048                         goto out_ro;
1049         }
1050
1051         finish_reservation(c);
1052
1053         mark_inode_clean(c, ubifs_inode(fst_dir));
1054         if (twoparents)
1055                 mark_inode_clean(c, ubifs_inode(snd_dir));
1056         kfree(dent1);
1057         return 0;
1058
1059 out_release:
1060         release_head(c, BASEHD);
1061 out_ro:
1062         ubifs_ro_mode(c, err);
1063         finish_reservation(c);
1064 out_free:
1065         kfree(dent1);
1066         return err;
1067 }
1068
1069 /**
1070  * ubifs_jnl_rename - rename a directory entry.
1071  * @c: UBIFS file-system description object
1072  * @old_dir: parent inode of directory entry to rename
1073  * @old_dentry: directory entry to rename
1074  * @new_dir: parent inode of directory entry to rename
1075  * @new_dentry: new directory entry (or directory entry to replace)
1076  * @sync: non-zero if the write-buffer has to be synchronized
1077  *
1078  * This function implements the re-name operation which may involve writing up
1079  * to 4 inodes and 2 directory entries. It marks the written inodes as clean
1080  * and returns zero on success. In case of failure, a negative error code is
1081  * returned.
1082  */
1083 int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
1084                      const struct inode *old_inode,
1085                      const struct fscrypt_name *old_nm,
1086                      const struct inode *new_dir,
1087                      const struct inode *new_inode,
1088                      const struct fscrypt_name *new_nm,
1089                      const struct inode *whiteout, int sync)
1090 {
1091         void *p;
1092         union ubifs_key key;
1093         struct ubifs_dent_node *dent, *dent2;
1094         int err, dlen1, dlen2, ilen, lnum, offs, len;
1095         int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
1096         int last_reference = !!(new_inode && new_inode->i_nlink == 0);
1097         int move = (old_dir != new_dir);
1098         struct ubifs_inode *uninitialized_var(new_ui);
1099
1100         ubifs_assert(ubifs_inode(old_dir)->data_len == 0);
1101         ubifs_assert(ubifs_inode(new_dir)->data_len == 0);
1102         ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
1103         ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
1104
1105         dlen1 = UBIFS_DENT_NODE_SZ + fname_len(new_nm) + 1;
1106         dlen2 = UBIFS_DENT_NODE_SZ + fname_len(old_nm) + 1;
1107         if (new_inode) {
1108                 new_ui = ubifs_inode(new_inode);
1109                 ubifs_assert(mutex_is_locked(&new_ui->ui_mutex));
1110                 ilen = UBIFS_INO_NODE_SZ;
1111                 if (!last_reference)
1112                         ilen += new_ui->data_len;
1113         } else
1114                 ilen = 0;
1115
1116         aligned_dlen1 = ALIGN(dlen1, 8);
1117         aligned_dlen2 = ALIGN(dlen2, 8);
1118         len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8);
1119         if (move)
1120                 len += plen;
1121         dent = kzalloc(len, GFP_NOFS);
1122         if (!dent)
1123                 return -ENOMEM;
1124
1125         /* Make reservation before allocating sequence numbers */
1126         err = make_reservation(c, BASEHD, len);
1127         if (err)
1128                 goto out_free;
1129
1130         /* Make new dent */
1131         dent->ch.node_type = UBIFS_DENT_NODE;
1132         dent_key_init_flash(c, &dent->key, new_dir->i_ino, new_nm);
1133         dent->inum = cpu_to_le64(old_inode->i_ino);
1134         dent->type = get_dent_type(old_inode->i_mode);
1135         dent->nlen = cpu_to_le16(fname_len(new_nm));
1136         memcpy(dent->name, fname_name(new_nm), fname_len(new_nm));
1137         dent->name[fname_len(new_nm)] = '\0';
1138         set_dent_cookie(c, dent);
1139         zero_dent_node_unused(dent);
1140         ubifs_prep_grp_node(c, dent, dlen1, 0);
1141
1142         dent2 = (void *)dent + aligned_dlen1;
1143         dent2->ch.node_type = UBIFS_DENT_NODE;
1144         dent_key_init_flash(c, &dent2->key, old_dir->i_ino, old_nm);
1145
1146         if (whiteout) {
1147                 dent2->inum = cpu_to_le64(whiteout->i_ino);
1148                 dent2->type = get_dent_type(whiteout->i_mode);
1149         } else {
1150                 /* Make deletion dent */
1151                 dent2->inum = 0;
1152                 dent2->type = DT_UNKNOWN;
1153         }
1154         dent2->nlen = cpu_to_le16(fname_len(old_nm));
1155         memcpy(dent2->name, fname_name(old_nm), fname_len(old_nm));
1156         dent2->name[fname_len(old_nm)] = '\0';
1157         set_dent_cookie(c, dent2);
1158         zero_dent_node_unused(dent2);
1159         ubifs_prep_grp_node(c, dent2, dlen2, 0);
1160
1161         p = (void *)dent2 + aligned_dlen2;
1162         if (new_inode) {
1163                 pack_inode(c, p, new_inode, 0);
1164                 p += ALIGN(ilen, 8);
1165         }
1166
1167         if (!move)
1168                 pack_inode(c, p, old_dir, 1);
1169         else {
1170                 pack_inode(c, p, old_dir, 0);
1171                 p += ALIGN(plen, 8);
1172                 pack_inode(c, p, new_dir, 1);
1173         }
1174
1175         if (last_reference) {
1176                 err = ubifs_add_orphan(c, new_inode->i_ino);
1177                 if (err) {
1178                         release_head(c, BASEHD);
1179                         goto out_finish;
1180                 }
1181                 new_ui->del_cmtno = c->cmt_no;
1182         }
1183
1184         err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
1185         if (err)
1186                 goto out_release;
1187         if (!sync) {
1188                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1189
1190                 ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
1191                 ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
1192                 if (new_inode)
1193                         ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
1194                                                   new_inode->i_ino);
1195         }
1196         release_head(c, BASEHD);
1197
1198         dent_key_init(c, &key, new_dir->i_ino, new_nm);
1199         err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, new_nm);
1200         if (err)
1201                 goto out_ro;
1202
1203         offs += aligned_dlen1;
1204         if (whiteout) {
1205                 dent_key_init(c, &key, old_dir->i_ino, old_nm);
1206                 err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen2, old_nm);
1207                 if (err)
1208                         goto out_ro;
1209
1210                 ubifs_delete_orphan(c, whiteout->i_ino);
1211         } else {
1212                 err = ubifs_add_dirt(c, lnum, dlen2);
1213                 if (err)
1214                         goto out_ro;
1215
1216                 dent_key_init(c, &key, old_dir->i_ino, old_nm);
1217                 err = ubifs_tnc_remove_nm(c, &key, old_nm);
1218                 if (err)
1219                         goto out_ro;
1220         }
1221
1222         offs += aligned_dlen2;
1223         if (new_inode) {
1224                 ino_key_init(c, &key, new_inode->i_ino);
1225                 err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
1226                 if (err)
1227                         goto out_ro;
1228                 offs += ALIGN(ilen, 8);
1229         }
1230
1231         ino_key_init(c, &key, old_dir->i_ino);
1232         err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1233         if (err)
1234                 goto out_ro;
1235
1236         if (move) {
1237                 offs += ALIGN(plen, 8);
1238                 ino_key_init(c, &key, new_dir->i_ino);
1239                 err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1240                 if (err)
1241                         goto out_ro;
1242         }
1243
1244         finish_reservation(c);
1245         if (new_inode) {
1246                 mark_inode_clean(c, new_ui);
1247                 spin_lock(&new_ui->ui_lock);
1248                 new_ui->synced_i_size = new_ui->ui_size;
1249                 spin_unlock(&new_ui->ui_lock);
1250         }
1251         mark_inode_clean(c, ubifs_inode(old_dir));
1252         if (move)
1253                 mark_inode_clean(c, ubifs_inode(new_dir));
1254         kfree(dent);
1255         return 0;
1256
1257 out_release:
1258         release_head(c, BASEHD);
1259 out_ro:
1260         ubifs_ro_mode(c, err);
1261         if (last_reference)
1262                 ubifs_delete_orphan(c, new_inode->i_ino);
1263 out_finish:
1264         finish_reservation(c);
1265 out_free:
1266         kfree(dent);
1267         return err;
1268 }
1269
1270 /**
1271  * truncate_data_node - re-compress/encrypt a truncated data node.
1272  * @c: UBIFS file-system description object
1273  * @inode: inode which referes to the data node
1274  * @block: data block number
1275  * @dn: data node to re-compress
1276  * @new_len: new length
1277  *
1278  * This function is used when an inode is truncated and the last data node of
1279  * the inode has to be re-compressed/encrypted and re-written.
1280  */
1281 static int truncate_data_node(const struct ubifs_info *c, const struct inode *inode,
1282                               unsigned int block, struct ubifs_data_node *dn,
1283                               int *new_len)
1284 {
1285         void *buf;
1286         int err, dlen, compr_type, out_len, old_dlen;
1287
1288         out_len = le32_to_cpu(dn->size);
1289         buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
1290         if (!buf)
1291                 return -ENOMEM;
1292
1293         dlen = old_dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
1294         compr_type = le16_to_cpu(dn->compr_type);
1295
1296         if (ubifs_crypt_is_encrypted(inode)) {
1297                 err = ubifs_decrypt(inode, dn, &dlen, block);
1298                 if (err)
1299                         goto out;
1300         }
1301
1302         if (compr_type == UBIFS_COMPR_NONE) {
1303                 out_len = *new_len;
1304         } else {
1305                 err = ubifs_decompress(c, &dn->data, dlen, buf, &out_len, compr_type);
1306                 if (err)
1307                         goto out;
1308
1309                 ubifs_compress(c, buf, *new_len, &dn->data, &out_len, &compr_type);
1310         }
1311
1312         if (ubifs_crypt_is_encrypted(inode)) {
1313                 err = ubifs_encrypt(inode, dn, out_len, &old_dlen, block);
1314                 if (err)
1315                         goto out;
1316
1317                 out_len = old_dlen;
1318         } else {
1319                 dn->compr_size = 0;
1320         }
1321
1322         ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
1323         dn->compr_type = cpu_to_le16(compr_type);
1324         dn->size = cpu_to_le32(*new_len);
1325         *new_len = UBIFS_DATA_NODE_SZ + out_len;
1326         err = 0;
1327 out:
1328         kfree(buf);
1329         return err;
1330 }
1331
1332 /**
1333  * ubifs_jnl_truncate - update the journal for a truncation.
1334  * @c: UBIFS file-system description object
1335  * @inode: inode to truncate
1336  * @old_size: old size
1337  * @new_size: new size
1338  *
1339  * When the size of a file decreases due to truncation, a truncation node is
1340  * written, the journal tree is updated, and the last data block is re-written
1341  * if it has been affected. The inode is also updated in order to synchronize
1342  * the new inode size.
1343  *
1344  * This function marks the inode as clean and returns zero on success. In case
1345  * of failure, a negative error code is returned.
1346  */
1347 int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1348                        loff_t old_size, loff_t new_size)
1349 {
1350         union ubifs_key key, to_key;
1351         struct ubifs_ino_node *ino;
1352         struct ubifs_trun_node *trun;
1353         struct ubifs_data_node *uninitialized_var(dn);
1354         int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
1355         struct ubifs_inode *ui = ubifs_inode(inode);
1356         ino_t inum = inode->i_ino;
1357         unsigned int blk;
1358
1359         dbg_jnl("ino %lu, size %lld -> %lld",
1360                 (unsigned long)inum, old_size, new_size);
1361         ubifs_assert(!ui->data_len);
1362         ubifs_assert(S_ISREG(inode->i_mode));
1363         ubifs_assert(mutex_is_locked(&ui->ui_mutex));
1364
1365         sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
1366              UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
1367         ino = kmalloc(sz, GFP_NOFS);
1368         if (!ino)
1369                 return -ENOMEM;
1370
1371         trun = (void *)ino + UBIFS_INO_NODE_SZ;
1372         trun->ch.node_type = UBIFS_TRUN_NODE;
1373         trun->inum = cpu_to_le32(inum);
1374         trun->old_size = cpu_to_le64(old_size);
1375         trun->new_size = cpu_to_le64(new_size);
1376         zero_trun_node_unused(trun);
1377
1378         dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
1379         if (dlen) {
1380                 /* Get last data block so it can be truncated */
1381                 dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
1382                 blk = new_size >> UBIFS_BLOCK_SHIFT;
1383                 data_key_init(c, &key, inum, blk);
1384                 dbg_jnlk(&key, "last block key ");
1385                 err = ubifs_tnc_lookup(c, &key, dn);
1386                 if (err == -ENOENT)
1387                         dlen = 0; /* Not found (so it is a hole) */
1388                 else if (err)
1389                         goto out_free;
1390                 else {
1391                         if (le32_to_cpu(dn->size) <= dlen)
1392                                 dlen = 0; /* Nothing to do */
1393                         else {
1394                                 err = truncate_data_node(c, inode, blk, dn, &dlen);
1395                                 if (err)
1396                                         goto out_free;
1397                         }
1398                 }
1399         }
1400
1401         /* Must make reservation before allocating sequence numbers */
1402         len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
1403         if (dlen)
1404                 len += dlen;
1405         err = make_reservation(c, BASEHD, len);
1406         if (err)
1407                 goto out_free;
1408
1409         pack_inode(c, ino, inode, 0);
1410         ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
1411         if (dlen)
1412                 ubifs_prep_grp_node(c, dn, dlen, 1);
1413
1414         err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
1415         if (err)
1416                 goto out_release;
1417         if (!sync)
1418                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
1419         release_head(c, BASEHD);
1420
1421         if (dlen) {
1422                 sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
1423                 err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
1424                 if (err)
1425                         goto out_ro;
1426         }
1427
1428         ino_key_init(c, &key, inum);
1429         err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
1430         if (err)
1431                 goto out_ro;
1432
1433         err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
1434         if (err)
1435                 goto out_ro;
1436
1437         bit = new_size & (UBIFS_BLOCK_SIZE - 1);
1438         blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
1439         data_key_init(c, &key, inum, blk);
1440
1441         bit = old_size & (UBIFS_BLOCK_SIZE - 1);
1442         blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0 : 1);
1443         data_key_init(c, &to_key, inum, blk);
1444
1445         err = ubifs_tnc_remove_range(c, &key, &to_key);
1446         if (err)
1447                 goto out_ro;
1448
1449         finish_reservation(c);
1450         spin_lock(&ui->ui_lock);
1451         ui->synced_i_size = ui->ui_size;
1452         spin_unlock(&ui->ui_lock);
1453         mark_inode_clean(c, ui);
1454         kfree(ino);
1455         return 0;
1456
1457 out_release:
1458         release_head(c, BASEHD);
1459 out_ro:
1460         ubifs_ro_mode(c, err);
1461         finish_reservation(c);
1462 out_free:
1463         kfree(ino);
1464         return err;
1465 }
1466
1467
1468 /**
1469  * ubifs_jnl_delete_xattr - delete an extended attribute.
1470  * @c: UBIFS file-system description object
1471  * @host: host inode
1472  * @inode: extended attribute inode
1473  * @nm: extended attribute entry name
1474  *
1475  * This function delete an extended attribute which is very similar to
1476  * un-linking regular files - it writes a deletion xentry, a deletion inode and
1477  * updates the target inode. Returns zero in case of success and a negative
1478  * error code in case of failure.
1479  */
1480 int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1481                            const struct inode *inode,
1482                            const struct fscrypt_name *nm)
1483 {
1484         int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
1485         struct ubifs_dent_node *xent;
1486         struct ubifs_ino_node *ino;
1487         union ubifs_key xent_key, key1, key2;
1488         int sync = IS_DIRSYNC(host);
1489         struct ubifs_inode *host_ui = ubifs_inode(host);
1490
1491         ubifs_assert(inode->i_nlink == 0);
1492         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1493
1494         /*
1495          * Since we are deleting the inode, we do not bother to attach any data
1496          * to it and assume its length is %UBIFS_INO_NODE_SZ.
1497          */
1498         xlen = UBIFS_DENT_NODE_SZ + fname_len(nm) + 1;
1499         aligned_xlen = ALIGN(xlen, 8);
1500         hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
1501         len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
1502
1503         xent = kzalloc(len, GFP_NOFS);
1504         if (!xent)
1505                 return -ENOMEM;
1506
1507         /* Make reservation before allocating sequence numbers */
1508         err = make_reservation(c, BASEHD, len);
1509         if (err) {
1510                 kfree(xent);
1511                 return err;
1512         }
1513
1514         xent->ch.node_type = UBIFS_XENT_NODE;
1515         xent_key_init(c, &xent_key, host->i_ino, nm);
1516         key_write(c, &xent_key, xent->key);
1517         xent->inum = 0;
1518         xent->type = get_dent_type(inode->i_mode);
1519         xent->nlen = cpu_to_le16(fname_len(nm));
1520         memcpy(xent->name, fname_name(nm), fname_len(nm));
1521         xent->name[fname_len(nm)] = '\0';
1522         zero_dent_node_unused(xent);
1523         ubifs_prep_grp_node(c, xent, xlen, 0);
1524
1525         ino = (void *)xent + aligned_xlen;
1526         pack_inode(c, ino, inode, 0);
1527         ino = (void *)ino + UBIFS_INO_NODE_SZ;
1528         pack_inode(c, ino, host, 1);
1529
1530         err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
1531         if (!sync && !err)
1532                 ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
1533         release_head(c, BASEHD);
1534         kfree(xent);
1535         if (err)
1536                 goto out_ro;
1537
1538         /* Remove the extended attribute entry from TNC */
1539         err = ubifs_tnc_remove_nm(c, &xent_key, nm);
1540         if (err)
1541                 goto out_ro;
1542         err = ubifs_add_dirt(c, lnum, xlen);
1543         if (err)
1544                 goto out_ro;
1545
1546         /*
1547          * Remove all nodes belonging to the extended attribute inode from TNC.
1548          * Well, there actually must be only one node - the inode itself.
1549          */
1550         lowest_ino_key(c, &key1, inode->i_ino);
1551         highest_ino_key(c, &key2, inode->i_ino);
1552         err = ubifs_tnc_remove_range(c, &key1, &key2);
1553         if (err)
1554                 goto out_ro;
1555         err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
1556         if (err)
1557                 goto out_ro;
1558
1559         /* And update TNC with the new host inode position */
1560         ino_key_init(c, &key1, host->i_ino);
1561         err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
1562         if (err)
1563                 goto out_ro;
1564
1565         finish_reservation(c);
1566         spin_lock(&host_ui->ui_lock);
1567         host_ui->synced_i_size = host_ui->ui_size;
1568         spin_unlock(&host_ui->ui_lock);
1569         mark_inode_clean(c, host_ui);
1570         return 0;
1571
1572 out_ro:
1573         ubifs_ro_mode(c, err);
1574         finish_reservation(c);
1575         return err;
1576 }
1577
1578 /**
1579  * ubifs_jnl_change_xattr - change an extended attribute.
1580  * @c: UBIFS file-system description object
1581  * @inode: extended attribute inode
1582  * @host: host inode
1583  *
1584  * This function writes the updated version of an extended attribute inode and
1585  * the host inode to the journal (to the base head). The host inode is written
1586  * after the extended attribute inode in order to guarantee that the extended
1587  * attribute will be flushed when the inode is synchronized by 'fsync()' and
1588  * consequently, the write-buffer is synchronized. This function returns zero
1589  * in case of success and a negative error code in case of failure.
1590  */
1591 int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
1592                            const struct inode *host)
1593 {
1594         int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
1595         struct ubifs_inode *host_ui = ubifs_inode(host);
1596         struct ubifs_ino_node *ino;
1597         union ubifs_key key;
1598         int sync = IS_DIRSYNC(host);
1599
1600         dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
1601         ubifs_assert(host->i_nlink > 0);
1602         ubifs_assert(inode->i_nlink > 0);
1603         ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1604
1605         len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
1606         len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
1607         aligned_len1 = ALIGN(len1, 8);
1608         aligned_len = aligned_len1 + ALIGN(len2, 8);
1609
1610         ino = kzalloc(aligned_len, GFP_NOFS);
1611         if (!ino)
1612                 return -ENOMEM;
1613
1614         /* Make reservation before allocating sequence numbers */
1615         err = make_reservation(c, BASEHD, aligned_len);
1616         if (err)
1617                 goto out_free;
1618
1619         pack_inode(c, ino, host, 0);
1620         pack_inode(c, (void *)ino + aligned_len1, inode, 1);
1621
1622         err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
1623         if (!sync && !err) {
1624                 struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1625
1626                 ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
1627                 ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
1628         }
1629         release_head(c, BASEHD);
1630         if (err)
1631                 goto out_ro;
1632
1633         ino_key_init(c, &key, host->i_ino);
1634         err = ubifs_tnc_add(c, &key, lnum, offs, len1);
1635         if (err)
1636                 goto out_ro;
1637
1638         ino_key_init(c, &key, inode->i_ino);
1639         err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
1640         if (err)
1641                 goto out_ro;
1642
1643         finish_reservation(c);
1644         spin_lock(&host_ui->ui_lock);
1645         host_ui->synced_i_size = host_ui->ui_size;
1646         spin_unlock(&host_ui->ui_lock);
1647         mark_inode_clean(c, host_ui);
1648         kfree(ino);
1649         return 0;
1650
1651 out_ro:
1652         ubifs_ro_mode(c, err);
1653         finish_reservation(c);
1654 out_free:
1655         kfree(ino);
1656         return err;
1657 }
1658