linux/fs/ubifs/journal.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * This file is part of UBIFS.
   4 *
   5 * Copyright (C) 2006-2008 Nokia Corporation.
   6 *
   7 * Authors: Artem Bityutskiy (Битюцкий Артём)
   8 *          Adrian Hunter
   9 */
  10
  11/*
  12 * This file implements UBIFS journal.
  13 *
  14 * The journal consists of 2 parts - the log and bud LEBs. The log has fixed
  15 * length and position, while a bud logical eraseblock is any LEB in the main
  16 * area. Buds contain file system data - data nodes, inode nodes, etc. The log
  17 * contains only references to buds and some other stuff like commit
  18 * start node. The idea is that when we commit the journal, we do
  19 * not copy the data, the buds just become indexed. Since after the commit the
  20 * nodes in bud eraseblocks become leaf nodes of the file system index tree, we
  21 * use term "bud". Analogy is obvious, bud eraseblocks contain nodes which will
  22 * become leafs in the future.
  23 *
  24 * The journal is multi-headed because we want to write data to the journal as
  25 * optimally as possible. It is nice to have nodes belonging to the same inode
  26 * in one LEB, so we may write data owned by different inodes to different
  27 * journal heads, although at present only one data head is used.
  28 *
  29 * For recovery reasons, the base head contains all inode nodes, all directory
  30 * entry nodes and all truncate nodes. This means that the other heads contain
  31 * only data nodes.
  32 *
  33 * Bud LEBs may be half-indexed. For example, if the bud was not full at the
  34 * time of commit, the bud is retained to continue to be used in the journal,
  35 * even though the "front" of the LEB is now indexed. In that case, the log
  36 * reference contains the offset where the bud starts for the purposes of the
  37 * journal.
  38 *
  39 * The journal size has to be limited, because the larger is the journal, the
  40 * longer it takes to mount UBIFS (scanning the journal) and the more memory it
  41 * takes (indexing in the TNC).
  42 *
  43 * All the journal write operations like 'ubifs_jnl_update()' here, which write
  44 * multiple UBIFS nodes to the journal at one go, are atomic with respect to
  45 * unclean reboots. Should the unclean reboot happen, the recovery code drops
  46 * all the nodes.
  47 */
  48
  49#include "ubifs.h"
  50
  51/**
  52 * zero_ino_node_unused - zero out unused fields of an on-flash inode node.
  53 * @ino: the inode to zero out
  54 */
  55static inline void zero_ino_node_unused(struct ubifs_ino_node *ino)
  56{
  57        memset(ino->padding1, 0, 4);
  58        memset(ino->padding2, 0, 26);
  59}
  60
  61/**
  62 * zero_dent_node_unused - zero out unused fields of an on-flash directory
  63 *                         entry node.
  64 * @dent: the directory entry to zero out
  65 */
  66static inline void zero_dent_node_unused(struct ubifs_dent_node *dent)
  67{
  68        dent->padding1 = 0;
  69}
  70
  71/**
  72 * zero_trun_node_unused - zero out unused fields of an on-flash truncation
  73 *                         node.
  74 * @trun: the truncation node to zero out
  75 */
  76static inline void zero_trun_node_unused(struct ubifs_trun_node *trun)
  77{
  78        memset(trun->padding, 0, 12);
  79}
  80
  81static void ubifs_add_auth_dirt(struct ubifs_info *c, int lnum)
  82{
  83        if (ubifs_authenticated(c))
  84                ubifs_add_dirt(c, lnum, ubifs_auth_node_sz(c));
  85}
  86
  87/**
  88 * reserve_space - reserve space in the journal.
  89 * @c: UBIFS file-system description object
  90 * @jhead: journal head number
  91 * @len: node length
  92 *
  93 * This function reserves space in journal head @head. If the reservation
  94 * succeeded, the journal head stays locked and later has to be unlocked using
  95 * 'release_head()'. Returns zero in case of success, %-EAGAIN if commit has to
  96 * be done, and other negative error codes in case of other failures.
  97 */
  98static int reserve_space(struct ubifs_info *c, int jhead, int len)
  99{
 100        int err = 0, err1, retries = 0, avail, lnum, offs, squeeze;
 101        struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 102
 103        /*
 104         * Typically, the base head has smaller nodes written to it, so it is
 105         * better to try to allocate space at the ends of eraseblocks. This is
 106         * what the squeeze parameter does.
 107         */
 108        ubifs_assert(c, !c->ro_media && !c->ro_mount);
 109        squeeze = (jhead == BASEHD);
 110again:
 111        mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 112
 113        if (c->ro_error) {
 114                err = -EROFS;
 115                goto out_unlock;
 116        }
 117
 118        avail = c->leb_size - wbuf->offs - wbuf->used;
 119        if (wbuf->lnum != -1 && avail >= len)
 120                return 0;
 121
 122        /*
 123         * Write buffer wasn't seek'ed or there is no enough space - look for an
 124         * LEB with some empty space.
 125         */
 126        lnum = ubifs_find_free_space(c, len, &offs, squeeze);
 127        if (lnum >= 0)
 128                goto out;
 129
 130        err = lnum;
 131        if (err != -ENOSPC)
 132                goto out_unlock;
 133
 134        /*
 135         * No free space, we have to run garbage collector to make
 136         * some. But the write-buffer mutex has to be unlocked because
 137         * GC also takes it.
 138         */
 139        dbg_jnl("no free space in jhead %s, run GC", dbg_jhead(jhead));
 140        mutex_unlock(&wbuf->io_mutex);
 141
 142        lnum = ubifs_garbage_collect(c, 0);
 143        if (lnum < 0) {
 144                err = lnum;
 145                if (err != -ENOSPC)
 146                        return err;
 147
 148                /*
 149                 * GC could not make a free LEB. But someone else may
 150                 * have allocated new bud for this journal head,
 151                 * because we dropped @wbuf->io_mutex, so try once
 152                 * again.
 153                 */
 154                dbg_jnl("GC couldn't make a free LEB for jhead %s",
 155                        dbg_jhead(jhead));
 156                if (retries++ < 2) {
 157                        dbg_jnl("retry (%d)", retries);
 158                        goto again;
 159                }
 160
 161                dbg_jnl("return -ENOSPC");
 162                return err;
 163        }
 164
 165        mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 166        dbg_jnl("got LEB %d for jhead %s", lnum, dbg_jhead(jhead));
 167        avail = c->leb_size - wbuf->offs - wbuf->used;
 168
 169        if (wbuf->lnum != -1 && avail >= len) {
 170                /*
 171                 * Someone else has switched the journal head and we have
 172                 * enough space now. This happens when more than one process is
 173                 * trying to write to the same journal head at the same time.
 174                 */
 175                dbg_jnl("return LEB %d back, already have LEB %d:%d",
 176                        lnum, wbuf->lnum, wbuf->offs + wbuf->used);
 177                err = ubifs_return_leb(c, lnum);
 178                if (err)
 179                        goto out_unlock;
 180                return 0;
 181        }
 182
 183        offs = 0;
 184
 185out:
 186        /*
 187         * Make sure we synchronize the write-buffer before we add the new bud
 188         * to the log. Otherwise we may have a power cut after the log
 189         * reference node for the last bud (@lnum) is written but before the
 190         * write-buffer data are written to the next-to-last bud
 191         * (@wbuf->lnum). And the effect would be that the recovery would see
 192         * that there is corruption in the next-to-last bud.
 193         */
 194        err = ubifs_wbuf_sync_nolock(wbuf);
 195        if (err)
 196                goto out_return;
 197        err = ubifs_add_bud_to_log(c, jhead, lnum, offs);
 198        if (err)
 199                goto out_return;
 200        err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs);
 201        if (err)
 202                goto out_unlock;
 203
 204        return 0;
 205
 206out_unlock:
 207        mutex_unlock(&wbuf->io_mutex);
 208        return err;
 209
 210out_return:
 211        /* An error occurred and the LEB has to be returned to lprops */
 212        ubifs_assert(c, err < 0);
 213        err1 = ubifs_return_leb(c, lnum);
 214        if (err1 && err == -EAGAIN)
 215                /*
 216                 * Return original error code only if it is not %-EAGAIN,
 217                 * which is not really an error. Otherwise, return the error
 218                 * code of 'ubifs_return_leb()'.
 219                 */
 220                err = err1;
 221        mutex_unlock(&wbuf->io_mutex);
 222        return err;
 223}
 224
 225static int ubifs_hash_nodes(struct ubifs_info *c, void *node,
 226                             int len, struct shash_desc *hash)
 227{
 228        int auth_node_size = ubifs_auth_node_sz(c);
 229        int err;
 230
 231        while (1) {
 232                const struct ubifs_ch *ch = node;
 233                int nodelen = le32_to_cpu(ch->len);
 234
 235                ubifs_assert(c, len >= auth_node_size);
 236
 237                if (len == auth_node_size)
 238                        break;
 239
 240                ubifs_assert(c, len > nodelen);
 241                ubifs_assert(c, ch->magic == cpu_to_le32(UBIFS_NODE_MAGIC));
 242
 243                err = ubifs_shash_update(c, hash, (void *)node, nodelen);
 244                if (err)
 245                        return err;
 246
 247                node += ALIGN(nodelen, 8);
 248                len -= ALIGN(nodelen, 8);
 249        }
 250
 251        return ubifs_prepare_auth_node(c, node, hash);
 252}
 253
 254/**
 255 * write_head - write data to a journal head.
 256 * @c: UBIFS file-system description object
 257 * @jhead: journal head
 258 * @buf: buffer to write
 259 * @len: length to write
 260 * @lnum: LEB number written is returned here
 261 * @offs: offset written is returned here
 262 * @sync: non-zero if the write-buffer has to by synchronized
 263 *
 264 * This function writes data to the reserved space of journal head @jhead.
 265 * Returns zero in case of success and a negative error code in case of
 266 * failure.
 267 */
 268static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
 269                      int *lnum, int *offs, int sync)
 270{
 271        int err;
 272        struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 273
 274        ubifs_assert(c, jhead != GCHD);
 275
 276        *lnum = c->jheads[jhead].wbuf.lnum;
 277        *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 278        dbg_jnl("jhead %s, LEB %d:%d, len %d",
 279                dbg_jhead(jhead), *lnum, *offs, len);
 280
 281        if (ubifs_authenticated(c)) {
 282                err = ubifs_hash_nodes(c, buf, len, c->jheads[jhead].log_hash);
 283                if (err)
 284                        return err;
 285        }
 286
 287        err = ubifs_wbuf_write_nolock(wbuf, buf, len);
 288        if (err)
 289                return err;
 290        if (sync)
 291                err = ubifs_wbuf_sync_nolock(wbuf);
 292        return err;
 293}
 294
 295/**
 296 * make_reservation - reserve journal space.
 297 * @c: UBIFS file-system description object
 298 * @jhead: journal head
 299 * @len: how many bytes to reserve
 300 *
 301 * This function makes space reservation in journal head @jhead. The function
 302 * takes the commit lock and locks the journal head, and the caller has to
 303 * unlock the head and finish the reservation with 'finish_reservation()'.
 304 * Returns zero in case of success and a negative error code in case of
 305 * failure.
 306 *
 307 * Note, the journal head may be unlocked as soon as the data is written, while
 308 * the commit lock has to be released after the data has been added to the
 309 * TNC.
 310 */
 311static int make_reservation(struct ubifs_info *c, int jhead, int len)
 312{
 313        int err, cmt_retries = 0, nospc_retries = 0;
 314
 315again:
 316        down_read(&c->commit_sem);
 317        err = reserve_space(c, jhead, len);
 318        if (!err)
 319                /* c->commit_sem will get released via finish_reservation(). */
 320                return 0;
 321        up_read(&c->commit_sem);
 322
 323        if (err == -ENOSPC) {
 324                /*
 325                 * GC could not make any progress. We should try to commit
 326                 * once because it could make some dirty space and GC would
 327                 * make progress, so make the error -EAGAIN so that the below
 328                 * will commit and re-try.
 329                 */
 330                if (nospc_retries++ < 2) {
 331                        dbg_jnl("no space, retry");
 332                        err = -EAGAIN;
 333                }
 334
 335                /*
 336                 * This means that the budgeting is incorrect. We always have
 337                 * to be able to write to the media, because all operations are
 338                 * budgeted. Deletions are not budgeted, though, but we reserve
 339                 * an extra LEB for them.
 340                 */
 341        }
 342
 343        if (err != -EAGAIN)
 344                goto out;
 345
 346        /*
 347         * -EAGAIN means that the journal is full or too large, or the above
 348         * code wants to do one commit. Do this and re-try.
 349         */
 350        if (cmt_retries > 128) {
 351                /*
 352                 * This should not happen unless the journal size limitations
 353                 * are too tough.
 354                 */
 355                ubifs_err(c, "stuck in space allocation");
 356                err = -ENOSPC;
 357                goto out;
 358        } else if (cmt_retries > 32)
 359                ubifs_warn(c, "too many space allocation re-tries (%d)",
 360                           cmt_retries);
 361
 362        dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
 363                cmt_retries);
 364        cmt_retries += 1;
 365
 366        err = ubifs_run_commit(c);
 367        if (err)
 368                return err;
 369        goto again;
 370
 371out:
 372        ubifs_err(c, "cannot reserve %d bytes in jhead %d, error %d",
 373                  len, jhead, err);
 374        if (err == -ENOSPC) {
 375                /* This are some budgeting problems, print useful information */
 376                down_write(&c->commit_sem);
 377                dump_stack();
 378                ubifs_dump_budg(c, &c->bi);
 379                ubifs_dump_lprops(c);
 380                cmt_retries = dbg_check_lprops(c);
 381                up_write(&c->commit_sem);
 382        }
 383        return err;
 384}
 385
 386/**
 387 * release_head - release a journal head.
 388 * @c: UBIFS file-system description object
 389 * @jhead: journal head
 390 *
 391 * This function releases journal head @jhead which was locked by
 392 * the 'make_reservation()' function. It has to be called after each successful
 393 * 'make_reservation()' invocation.
 394 */
 395static inline void release_head(struct ubifs_info *c, int jhead)
 396{
 397        mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
 398}
 399
 400/**
 401 * finish_reservation - finish a reservation.
 402 * @c: UBIFS file-system description object
 403 *
 404 * This function finishes journal space reservation. It must be called after
 405 * 'make_reservation()'.
 406 */
 407static void finish_reservation(struct ubifs_info *c)
 408{
 409        up_read(&c->commit_sem);
 410}
 411
 412/**
 413 * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
 414 * @mode: inode mode
 415 */
 416static int get_dent_type(int mode)
 417{
 418        switch (mode & S_IFMT) {
 419        case S_IFREG:
 420                return UBIFS_ITYPE_REG;
 421        case S_IFDIR:
 422                return UBIFS_ITYPE_DIR;
 423        case S_IFLNK:
 424                return UBIFS_ITYPE_LNK;
 425        case S_IFBLK:
 426                return UBIFS_ITYPE_BLK;
 427        case S_IFCHR:
 428                return UBIFS_ITYPE_CHR;
 429        case S_IFIFO:
 430                return UBIFS_ITYPE_FIFO;
 431        case S_IFSOCK:
 432                return UBIFS_ITYPE_SOCK;
 433        default:
 434                BUG();
 435        }
 436        return 0;
 437}
 438
 439/**
 440 * pack_inode - pack an inode node.
 441 * @c: UBIFS file-system description object
 442 * @ino: buffer in which to pack inode node
 443 * @inode: inode to pack
 444 * @last: indicates the last node of the group
 445 */
 446static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
 447                       const struct inode *inode, int last)
 448{
 449        int data_len = 0, last_reference = !inode->i_nlink;
 450        struct ubifs_inode *ui = ubifs_inode(inode);
 451
 452        ino->ch.node_type = UBIFS_INO_NODE;
 453        ino_key_init_flash(c, &ino->key, inode->i_ino);
 454        ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum);
 455        ino->atime_sec  = cpu_to_le64(inode->i_atime.tv_sec);
 456        ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
 457        ino->ctime_sec  = cpu_to_le64(inode->i_ctime.tv_sec);
 458        ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 459        ino->mtime_sec  = cpu_to_le64(inode->i_mtime.tv_sec);
 460        ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 461        ino->uid   = cpu_to_le32(i_uid_read(inode));
 462        ino->gid   = cpu_to_le32(i_gid_read(inode));
 463        ino->mode  = cpu_to_le32(inode->i_mode);
 464        ino->flags = cpu_to_le32(ui->flags);
 465        ino->size  = cpu_to_le64(ui->ui_size);
 466        ino->nlink = cpu_to_le32(inode->i_nlink);
 467        ino->compr_type  = cpu_to_le16(ui->compr_type);
 468        ino->data_len    = cpu_to_le32(ui->data_len);
 469        ino->xattr_cnt   = cpu_to_le32(ui->xattr_cnt);
 470        ino->xattr_size  = cpu_to_le32(ui->xattr_size);
 471        ino->xattr_names = cpu_to_le32(ui->xattr_names);
 472        zero_ino_node_unused(ino);
 473
 474        /*
 475         * Drop the attached data if this is a deletion inode, the data is not
 476         * needed anymore.
 477         */
 478        if (!last_reference) {
 479                memcpy(ino->data, ui->data, ui->data_len);
 480                data_len = ui->data_len;
 481        }
 482
 483        ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last);
 484}
 485
 486/**
 487 * mark_inode_clean - mark UBIFS inode as clean.
 488 * @c: UBIFS file-system description object
 489 * @ui: UBIFS inode to mark as clean
 490 *
 491 * This helper function marks UBIFS inode @ui as clean by cleaning the
 492 * @ui->dirty flag and releasing its budget. Note, VFS may still treat the
 493 * inode as dirty and try to write it back, but 'ubifs_write_inode()' would
 494 * just do nothing.
 495 */
 496static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui)
 497{
 498        if (ui->dirty)
 499                ubifs_release_dirty_inode_budget(c, ui);
 500        ui->dirty = 0;
 501}
 502
 503static void set_dent_cookie(struct ubifs_info *c, struct ubifs_dent_node *dent)
 504{
 505        if (c->double_hash)
 506                dent->cookie = (__force __le32) prandom_u32();
 507        else
 508                dent->cookie = 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 */
 538int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
 539                     const struct fscrypt_name *nm, const struct inode *inode,
 540                     int deletion, int xent)
 541{
 542        int err, dlen, ilen, len, lnum, ino_offs, dent_offs, orphan_added = 0;
 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 *host_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        u8 hash_dent[UBIFS_HASH_ARR_SZ];
 551        u8 hash_ino[UBIFS_HASH_ARR_SZ];
 552        u8 hash_ino_host[UBIFS_HASH_ARR_SZ];
 553
 554        ubifs_assert(c, mutex_is_locked(&host_ui->ui_mutex));
 555
 556        dlen = UBIFS_DENT_NODE_SZ + fname_len(nm) + 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
 573        len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ;
 574        /* Make sure to also account for extended attributes */
 575        if (ubifs_authenticated(c))
 576                len += ALIGN(host_ui->data_len, 8) + ubifs_auth_node_sz(c);
 577        else
 578                len += host_ui->data_len;
 579
 580        dent = kzalloc(len, GFP_NOFS);
 581        if (!dent)
 582                return -ENOMEM;
 583
 584        /* Make reservation before allocating sequence numbers */
 585        err = make_reservation(c, BASEHD, len);
 586        if (err)
 587                goto out_free;
 588
 589        if (!xent) {
 590                dent->ch.node_type = UBIFS_DENT_NODE;
 591                if (fname_name(nm) == NULL)
 592                        dent_key_init_hash(c, &dent_key, dir->i_ino, nm->hash);
 593                else
 594                        dent_key_init(c, &dent_key, dir->i_ino, nm);
 595        } else {
 596                dent->ch.node_type = UBIFS_XENT_NODE;
 597                xent_key_init(c, &dent_key, dir->i_ino, nm);
 598        }
 599
 600        key_write(c, &dent_key, dent->key);
 601        dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino);
 602        dent->type = get_dent_type(inode->i_mode);
 603        dent->nlen = cpu_to_le16(fname_len(nm));
 604        memcpy(dent->name, fname_name(nm), fname_len(nm));
 605        dent->name[fname_len(nm)] = '\0';
 606        set_dent_cookie(c, dent);
 607
 608        zero_dent_node_unused(dent);
 609        ubifs_prep_grp_node(c, dent, dlen, 0);
 610        err = ubifs_node_calc_hash(c, dent, hash_dent);
 611        if (err)
 612                goto out_release;
 613
 614        ino = (void *)dent + aligned_dlen;
 615        pack_inode(c, ino, inode, 0);
 616        err = ubifs_node_calc_hash(c, ino, hash_ino);
 617        if (err)
 618                goto out_release;
 619
 620        ino = (void *)ino + aligned_ilen;
 621        pack_inode(c, ino, dir, 1);
 622        err = ubifs_node_calc_hash(c, ino, hash_ino_host);
 623        if (err)
 624                goto out_release;
 625
 626        if (last_reference) {
 627                err = ubifs_add_orphan(c, inode->i_ino);
 628                if (err) {
 629                        release_head(c, BASEHD);
 630                        goto out_finish;
 631                }
 632                ui->del_cmtno = c->cmt_no;
 633                orphan_added = 1;
 634        }
 635
 636        err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
 637        if (err)
 638                goto out_release;
 639        if (!sync) {
 640                struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
 641
 642                ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
 643                ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
 644        }
 645        release_head(c, BASEHD);
 646        kfree(dent);
 647        ubifs_add_auth_dirt(c, lnum);
 648
 649        if (deletion) {
 650                if (fname_name(nm) == NULL)
 651                        err = ubifs_tnc_remove_dh(c, &dent_key, nm->minor_hash);
 652                else
 653                        err = ubifs_tnc_remove_nm(c, &dent_key, nm);
 654                if (err)
 655                        goto out_ro;
 656                err = ubifs_add_dirt(c, lnum, dlen);
 657        } else
 658                err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen,
 659                                       hash_dent, nm);
 660        if (err)
 661                goto out_ro;
 662
 663        /*
 664         * Note, we do not remove the inode from TNC even if the last reference
 665         * to it has just been deleted, because the inode may still be opened.
 666         * Instead, the inode has been added to orphan lists and the orphan
 667         * subsystem will take further care about it.
 668         */
 669        ino_key_init(c, &ino_key, inode->i_ino);
 670        ino_offs = dent_offs + aligned_dlen;
 671        err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen, hash_ino);
 672        if (err)
 673                goto out_ro;
 674
 675        ino_key_init(c, &ino_key, dir->i_ino);
 676        ino_offs += aligned_ilen;
 677        err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs,
 678                            UBIFS_INO_NODE_SZ + host_ui->data_len, hash_ino_host);
 679        if (err)
 680                goto out_ro;
 681
 682        finish_reservation(c);
 683        spin_lock(&ui->ui_lock);
 684        ui->synced_i_size = ui->ui_size;
 685        spin_unlock(&ui->ui_lock);
 686        if (xent) {
 687                spin_lock(&host_ui->ui_lock);
 688                host_ui->synced_i_size = host_ui->ui_size;
 689                spin_unlock(&host_ui->ui_lock);
 690        }
 691        mark_inode_clean(c, ui);
 692        mark_inode_clean(c, host_ui);
 693        return 0;
 694
 695out_finish:
 696        finish_reservation(c);
 697out_free:
 698        kfree(dent);
 699        return err;
 700
 701out_release:
 702        release_head(c, BASEHD);
 703        kfree(dent);
 704out_ro:
 705        ubifs_ro_mode(c, err);
 706        if (orphan_added)
 707                ubifs_delete_orphan(c, inode->i_ino);
 708        finish_reservation(c);
 709        return err;
 710}
 711
 712/**
 713 * ubifs_jnl_write_data - write a data node to the journal.
 714 * @c: UBIFS file-system description object
 715 * @inode: inode the data node belongs to
 716 * @key: node key
 717 * @buf: buffer to write
 718 * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
 719 *
 720 * This function writes a data node to the journal. Returns %0 if the data node
 721 * was successfully written, and a negative error code in case of failure.
 722 */
 723int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
 724                         const union ubifs_key *key, const void *buf, int len)
 725{
 726        struct ubifs_data_node *data;
 727        int err, lnum, offs, compr_type, out_len, compr_len, auth_len;
 728        int dlen = COMPRESSED_DATA_NODE_BUF_SZ, allocated = 1;
 729        int write_len;
 730        struct ubifs_inode *ui = ubifs_inode(inode);
 731        bool encrypted = IS_ENCRYPTED(inode);
 732        u8 hash[UBIFS_HASH_ARR_SZ];
 733
 734        dbg_jnlk(key, "ino %lu, blk %u, len %d, key ",
 735                (unsigned long)key_inum(c, key), key_block(c, key), len);
 736        ubifs_assert(c, len <= UBIFS_BLOCK_SIZE);
 737
 738        if (encrypted)
 739                dlen += UBIFS_CIPHER_BLOCK_SIZE;
 740
 741        auth_len = ubifs_auth_node_sz(c);
 742
 743        data = kmalloc(dlen + auth_len, GFP_NOFS | __GFP_NOWARN);
 744        if (!data) {
 745                /*
 746                 * Fall-back to the write reserve buffer. Note, we might be
 747                 * currently on the memory reclaim path, when the kernel is
 748                 * trying to free some memory by writing out dirty pages. The
 749                 * write reserve buffer helps us to guarantee that we are
 750                 * always able to write the data.
 751                 */
 752                allocated = 0;
 753                mutex_lock(&c->write_reserve_mutex);
 754                data = c->write_reserve_buf;
 755        }
 756
 757        data->ch.node_type = UBIFS_DATA_NODE;
 758        key_write(c, key, &data->key);
 759        data->size = cpu_to_le32(len);
 760
 761        if (!(ui->flags & UBIFS_COMPR_FL))
 762                /* Compression is disabled for this inode */
 763                compr_type = UBIFS_COMPR_NONE;
 764        else
 765                compr_type = ui->compr_type;
 766
 767        out_len = compr_len = dlen - UBIFS_DATA_NODE_SZ;
 768        ubifs_compress(c, buf, len, &data->data, &compr_len, &compr_type);
 769        ubifs_assert(c, compr_len <= UBIFS_BLOCK_SIZE);
 770
 771        if (encrypted) {
 772                err = ubifs_encrypt(inode, data, compr_len, &out_len, key_block(c, key));
 773                if (err)
 774                        goto out_free;
 775
 776        } else {
 777                data->compr_size = 0;
 778                out_len = compr_len;
 779        }
 780
 781        dlen = UBIFS_DATA_NODE_SZ + out_len;
 782        if (ubifs_authenticated(c))
 783                write_len = ALIGN(dlen, 8) + auth_len;
 784        else
 785                write_len = dlen;
 786
 787        data->compr_type = cpu_to_le16(compr_type);
 788
 789        /* Make reservation before allocating sequence numbers */
 790        err = make_reservation(c, DATAHD, write_len);
 791        if (err)
 792                goto out_free;
 793
 794        ubifs_prepare_node(c, data, dlen, 0);
 795        err = write_head(c, DATAHD, data, write_len, &lnum, &offs, 0);
 796        if (err)
 797                goto out_release;
 798
 799        err = ubifs_node_calc_hash(c, data, hash);
 800        if (err)
 801                goto out_release;
 802
 803        ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
 804        release_head(c, DATAHD);
 805
 806        ubifs_add_auth_dirt(c, lnum);
 807
 808        err = ubifs_tnc_add(c, key, lnum, offs, dlen, hash);
 809        if (err)
 810                goto out_ro;
 811
 812        finish_reservation(c);
 813        if (!allocated)
 814                mutex_unlock(&c->write_reserve_mutex);
 815        else
 816                kfree(data);
 817        return 0;
 818
 819out_release:
 820        release_head(c, DATAHD);
 821out_ro:
 822        ubifs_ro_mode(c, err);
 823        finish_reservation(c);
 824out_free:
 825        if (!allocated)
 826                mutex_unlock(&c->write_reserve_mutex);
 827        else
 828                kfree(data);
 829        return err;
 830}
 831
 832/**
 833 * ubifs_jnl_write_inode - flush inode to the journal.
 834 * @c: UBIFS file-system description object
 835 * @inode: inode to flush
 836 *
 837 * This function writes inode @inode to the journal. If the inode is
 838 * synchronous, it also synchronizes the write-buffer. Returns zero in case of
 839 * success and a negative error code in case of failure.
 840 */
 841int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode)
 842{
 843        int err, lnum, offs;
 844        struct ubifs_ino_node *ino, *ino_start;
 845        struct ubifs_inode *ui = ubifs_inode(inode);
 846        int sync = 0, write_len = 0, ilen = UBIFS_INO_NODE_SZ;
 847        int last_reference = !inode->i_nlink;
 848        int kill_xattrs = ui->xattr_cnt && last_reference;
 849        u8 hash[UBIFS_HASH_ARR_SZ];
 850
 851        dbg_jnl("ino %lu, nlink %u", inode->i_ino, inode->i_nlink);
 852
 853        /*
 854         * If the inode is being deleted, do not write the attached data. No
 855         * need to synchronize the write-buffer either.
 856         */
 857        if (!last_reference) {
 858                ilen += ui->data_len;
 859                sync = IS_SYNC(inode);
 860        } else if (kill_xattrs) {
 861                write_len += UBIFS_INO_NODE_SZ * ui->xattr_cnt;
 862        }
 863
 864        if (ubifs_authenticated(c))
 865                write_len += ALIGN(ilen, 8) + ubifs_auth_node_sz(c);
 866        else
 867                write_len += ilen;
 868
 869        ino_start = ino = kmalloc(write_len, GFP_NOFS);
 870        if (!ino)
 871                return -ENOMEM;
 872
 873        /* Make reservation before allocating sequence numbers */
 874        err = make_reservation(c, BASEHD, write_len);
 875        if (err)
 876                goto out_free;
 877
 878        if (kill_xattrs) {
 879                union ubifs_key key;
 880                struct fscrypt_name nm = {0};
 881                struct inode *xino;
 882                struct ubifs_dent_node *xent, *pxent = NULL;
 883
 884                if (ui->xattr_cnt > ubifs_xattr_max_cnt(c)) {
 885                        err = -EPERM;
 886                        ubifs_err(c, "Cannot delete inode, it has too much xattrs!");
 887                        goto out_release;
 888                }
 889
 890                lowest_xent_key(c, &key, inode->i_ino);
 891                while (1) {
 892                        xent = ubifs_tnc_next_ent(c, &key, &nm);
 893                        if (IS_ERR(xent)) {
 894                                err = PTR_ERR(xent);
 895                                if (err == -ENOENT)
 896                                        break;
 897
 898                                kfree(pxent);
 899                                goto out_release;
 900                        }
 901
 902                        fname_name(&nm) = xent->name;
 903                        fname_len(&nm) = le16_to_cpu(xent->nlen);
 904
 905                        xino = ubifs_iget(c->vfs_sb, le64_to_cpu(xent->inum));
 906                        if (IS_ERR(xino)) {
 907                                err = PTR_ERR(xino);
 908                                ubifs_err(c, "dead directory entry '%s', error %d",
 909                                          xent->name, err);
 910                                ubifs_ro_mode(c, err);
 911                                kfree(pxent);
 912                                kfree(xent);
 913                                goto out_release;
 914                        }
 915                        ubifs_assert(c, ubifs_inode(xino)->xattr);
 916
 917                        clear_nlink(xino);
 918                        pack_inode(c, ino, xino, 0);
 919                        ino = (void *)ino + UBIFS_INO_NODE_SZ;
 920                        iput(xino);
 921
 922                        kfree(pxent);
 923                        pxent = xent;
 924                        key_read(c, &xent->key, &key);
 925                }
 926                kfree(pxent);
 927        }
 928
 929        pack_inode(c, ino, inode, 1);
 930        err = ubifs_node_calc_hash(c, ino, hash);
 931        if (err)
 932                goto out_release;
 933
 934        err = write_head(c, BASEHD, ino_start, write_len, &lnum, &offs, sync);
 935        if (err)
 936                goto out_release;
 937        if (!sync)
 938                ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
 939                                          inode->i_ino);
 940        release_head(c, BASEHD);
 941
 942        if (last_reference) {
 943                err = ubifs_tnc_remove_ino(c, inode->i_ino);
 944                if (err)
 945                        goto out_ro;
 946                ubifs_delete_orphan(c, inode->i_ino);
 947                err = ubifs_add_dirt(c, lnum, write_len);
 948        } else {
 949                union ubifs_key key;
 950
 951                ubifs_add_auth_dirt(c, lnum);
 952
 953                ino_key_init(c, &key, inode->i_ino);
 954                err = ubifs_tnc_add(c, &key, lnum, offs, ilen, hash);
 955        }
 956        if (err)
 957                goto out_ro;
 958
 959        finish_reservation(c);
 960        spin_lock(&ui->ui_lock);
 961        ui->synced_i_size = ui->ui_size;
 962        spin_unlock(&ui->ui_lock);
 963        kfree(ino_start);
 964        return 0;
 965
 966out_release:
 967        release_head(c, BASEHD);
 968out_ro:
 969        ubifs_ro_mode(c, err);
 970        finish_reservation(c);
 971out_free:
 972        kfree(ino_start);
 973        return err;
 974}
 975
 976/**
 977 * ubifs_jnl_delete_inode - delete an inode.
 978 * @c: UBIFS file-system description object
 979 * @inode: inode to delete
 980 *
 981 * This function deletes inode @inode which includes removing it from orphans,
 982 * deleting it from TNC and, in some cases, writing a deletion inode to the
 983 * journal.
 984 *
 985 * When regular file inodes are unlinked or a directory inode is removed, the
 986 * 'ubifs_jnl_update()' function writes a corresponding deletion inode and
 987 * direntry to the media, and adds the inode to orphans. After this, when the
 988 * last reference to this inode has been dropped, this function is called. In
 989 * general, it has to write one more deletion inode to the media, because if
 990 * a commit happened between 'ubifs_jnl_update()' and
 991 * 'ubifs_jnl_delete_inode()', the deletion inode is not in the journal
 992 * anymore, and in fact it might not be on the flash anymore, because it might
 993 * have been garbage-collected already. And for optimization reasons UBIFS does
 994 * not read the orphan area if it has been unmounted cleanly, so it would have
 995 * no indication in the journal that there is a deleted inode which has to be
 996 * removed from TNC.
 997 *
 998 * However, if there was no commit between 'ubifs_jnl_update()' and
 999 * 'ubifs_jnl_delete_inode()', then there is no need to write the deletion
1000 * inode to the media for the second time. And this is quite a typical case.
1001 *
1002 * This function returns zero in case of success and a negative error code in
1003 * case of failure.
1004 */
1005int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode)
1006{
1007        int err;
1008        struct ubifs_inode *ui = ubifs_inode(inode);
1009
1010        ubifs_assert(c, inode->i_nlink == 0);
1011
1012        if (ui->xattr_cnt || ui->del_cmtno != c->cmt_no)
1013                /* A commit happened for sure or inode hosts xattrs */
1014                return ubifs_jnl_write_inode(c, inode);
1015
1016        down_read(&c->commit_sem);
1017        /*
1018         * Check commit number again, because the first test has been done
1019         * without @c->commit_sem, so a commit might have happened.
1020         */
1021        if (ui->del_cmtno != c->cmt_no) {
1022                up_read(&c->commit_sem);
1023                return ubifs_jnl_write_inode(c, inode);
1024        }
1025
1026        err = ubifs_tnc_remove_ino(c, inode->i_ino);
1027        if (err)
1028                ubifs_ro_mode(c, err);
1029        else
1030                ubifs_delete_orphan(c, inode->i_ino);
1031        up_read(&c->commit_sem);
1032        return err;
1033}
1034
1035/**
1036 * ubifs_jnl_xrename - cross rename two directory entries.
1037 * @c: UBIFS file-system description object
1038 * @fst_dir: parent inode of 1st directory entry to exchange
1039 * @fst_inode: 1st inode to exchange
1040 * @fst_nm: name of 1st inode to exchange
1041 * @snd_dir: parent inode of 2nd directory entry to exchange
1042 * @snd_inode: 2nd inode to exchange
1043 * @snd_nm: name of 2nd inode to exchange
1044 * @sync: non-zero if the write-buffer has to be synchronized
1045 *
1046 * This function implements the cross rename operation which may involve
1047 * writing 2 inodes and 2 directory entries. It marks the written inodes as clean
1048 * and returns zero on success. In case of failure, a negative error code is
1049 * returned.
1050 */
1051int ubifs_jnl_xrename(struct ubifs_info *c, const struct inode *fst_dir,
1052                      const struct inode *fst_inode,
1053                      const struct fscrypt_name *fst_nm,
1054                      const struct inode *snd_dir,
1055                      const struct inode *snd_inode,
1056                      const struct fscrypt_name *snd_nm, int sync)
1057{
1058        union ubifs_key key;
1059        struct ubifs_dent_node *dent1, *dent2;
1060        int err, dlen1, dlen2, lnum, offs, len, plen = UBIFS_INO_NODE_SZ;
1061        int aligned_dlen1, aligned_dlen2;
1062        int twoparents = (fst_dir != snd_dir);
1063        void *p;
1064        u8 hash_dent1[UBIFS_HASH_ARR_SZ];
1065        u8 hash_dent2[UBIFS_HASH_ARR_SZ];
1066        u8 hash_p1[UBIFS_HASH_ARR_SZ];
1067        u8 hash_p2[UBIFS_HASH_ARR_SZ];
1068
1069        ubifs_assert(c, ubifs_inode(fst_dir)->data_len == 0);
1070        ubifs_assert(c, ubifs_inode(snd_dir)->data_len == 0);
1071        ubifs_assert(c, mutex_is_locked(&ubifs_inode(fst_dir)->ui_mutex));
1072        ubifs_assert(c, mutex_is_locked(&ubifs_inode(snd_dir)->ui_mutex));
1073
1074        dlen1 = UBIFS_DENT_NODE_SZ + fname_len(snd_nm) + 1;
1075        dlen2 = UBIFS_DENT_NODE_SZ + fname_len(fst_nm) + 1;
1076        aligned_dlen1 = ALIGN(dlen1, 8);
1077        aligned_dlen2 = ALIGN(dlen2, 8);
1078
1079        len = aligned_dlen1 + aligned_dlen2 + ALIGN(plen, 8);
1080        if (twoparents)
1081                len += plen;
1082
1083        len += ubifs_auth_node_sz(c);
1084
1085        dent1 = kzalloc(len, GFP_NOFS);
1086        if (!dent1)
1087                return -ENOMEM;
1088
1089        /* Make reservation before allocating sequence numbers */
1090        err = make_reservation(c, BASEHD, len);
1091        if (err)
1092                goto out_free;
1093
1094        /* Make new dent for 1st entry */
1095        dent1->ch.node_type = UBIFS_DENT_NODE;
1096        dent_key_init_flash(c, &dent1->key, snd_dir->i_ino, snd_nm);
1097        dent1->inum = cpu_to_le64(fst_inode->i_ino);
1098        dent1->type = get_dent_type(fst_inode->i_mode);
1099        dent1->nlen = cpu_to_le16(fname_len(snd_nm));
1100        memcpy(dent1->name, fname_name(snd_nm), fname_len(snd_nm));
1101        dent1->name[fname_len(snd_nm)] = '\0';
1102        set_dent_cookie(c, dent1);
1103        zero_dent_node_unused(dent1);
1104        ubifs_prep_grp_node(c, dent1, dlen1, 0);
1105        err = ubifs_node_calc_hash(c, dent1, hash_dent1);
1106        if (err)
1107                goto out_release;
1108
1109        /* Make new dent for 2nd entry */
1110        dent2 = (void *)dent1 + aligned_dlen1;
1111        dent2->ch.node_type = UBIFS_DENT_NODE;
1112        dent_key_init_flash(c, &dent2->key, fst_dir->i_ino, fst_nm);
1113        dent2->inum = cpu_to_le64(snd_inode->i_ino);
1114        dent2->type = get_dent_type(snd_inode->i_mode);
1115        dent2->nlen = cpu_to_le16(fname_len(fst_nm));
1116        memcpy(dent2->name, fname_name(fst_nm), fname_len(fst_nm));
1117        dent2->name[fname_len(fst_nm)] = '\0';
1118        set_dent_cookie(c, dent2);
1119        zero_dent_node_unused(dent2);
1120        ubifs_prep_grp_node(c, dent2, dlen2, 0);
1121        err = ubifs_node_calc_hash(c, dent2, hash_dent2);
1122        if (err)
1123                goto out_release;
1124
1125        p = (void *)dent2 + aligned_dlen2;
1126        if (!twoparents) {
1127                pack_inode(c, p, fst_dir, 1);
1128                err = ubifs_node_calc_hash(c, p, hash_p1);
1129                if (err)
1130                        goto out_release;
1131        } else {
1132                pack_inode(c, p, fst_dir, 0);
1133                err = ubifs_node_calc_hash(c, p, hash_p1);
1134                if (err)
1135                        goto out_release;
1136                p += ALIGN(plen, 8);
1137                pack_inode(c, p, snd_dir, 1);
1138                err = ubifs_node_calc_hash(c, p, hash_p2);
1139                if (err)
1140                        goto out_release;
1141        }
1142
1143        err = write_head(c, BASEHD, dent1, len, &lnum, &offs, sync);
1144        if (err)
1145                goto out_release;
1146        if (!sync) {
1147                struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1148
1149                ubifs_wbuf_add_ino_nolock(wbuf, fst_dir->i_ino);
1150                ubifs_wbuf_add_ino_nolock(wbuf, snd_dir->i_ino);
1151        }
1152        release_head(c, BASEHD);
1153
1154        ubifs_add_auth_dirt(c, lnum);
1155
1156        dent_key_init(c, &key, snd_dir->i_ino, snd_nm);
1157        err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, hash_dent1, snd_nm);
1158        if (err)
1159                goto out_ro;
1160
1161        offs += aligned_dlen1;
1162        dent_key_init(c, &key, fst_dir->i_ino, fst_nm);
1163        err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen2, hash_dent2, fst_nm);
1164        if (err)
1165                goto out_ro;
1166
1167        offs += aligned_dlen2;
1168
1169        ino_key_init(c, &key, fst_dir->i_ino);
1170        err = ubifs_tnc_add(c, &key, lnum, offs, plen, hash_p1);
1171        if (err)
1172                goto out_ro;
1173
1174        if (twoparents) {
1175                offs += ALIGN(plen, 8);
1176                ino_key_init(c, &key, snd_dir->i_ino);
1177                err = ubifs_tnc_add(c, &key, lnum, offs, plen, hash_p2);
1178                if (err)
1179                        goto out_ro;
1180        }
1181
1182        finish_reservation(c);
1183
1184        mark_inode_clean(c, ubifs_inode(fst_dir));
1185        if (twoparents)
1186                mark_inode_clean(c, ubifs_inode(snd_dir));
1187        kfree(dent1);
1188        return 0;
1189
1190out_release:
1191        release_head(c, BASEHD);
1192out_ro:
1193        ubifs_ro_mode(c, err);
1194        finish_reservation(c);
1195out_free:
1196        kfree(dent1);
1197        return err;
1198}
1199
1200/**
1201 * ubifs_jnl_rename - rename a directory entry.
1202 * @c: UBIFS file-system description object
1203 * @old_dir: parent inode of directory entry to rename
1204 * @old_dentry: directory entry to rename
1205 * @new_dir: parent inode of directory entry to rename
1206 * @new_dentry: new directory entry (or directory entry to replace)
1207 * @sync: non-zero if the write-buffer has to be synchronized
1208 *
1209 * This function implements the re-name operation which may involve writing up
1210 * to 4 inodes(new inode, whiteout inode, old and new parent directory inodes)
1211 * and 2 directory entries. It marks the written inodes as clean and returns
1212 * zero on success. In case of failure, a negative error code is returned.
1213 */
1214int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
1215                     const struct inode *old_inode,
1216                     const struct fscrypt_name *old_nm,
1217                     const struct inode *new_dir,
1218                     const struct inode *new_inode,
1219                     const struct fscrypt_name *new_nm,
1220                     const struct inode *whiteout, int sync)
1221{
1222        void *p;
1223        union ubifs_key key;
1224        struct ubifs_dent_node *dent, *dent2;
1225        int err, dlen1, dlen2, ilen, wlen, lnum, offs, len, orphan_added = 0;
1226        int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
1227        int last_reference = !!(new_inode && new_inode->i_nlink == 0);
1228        int move = (old_dir != new_dir);
1229        struct ubifs_inode *new_ui, *whiteout_ui;
1230        u8 hash_old_dir[UBIFS_HASH_ARR_SZ];
1231        u8 hash_new_dir[UBIFS_HASH_ARR_SZ];
1232        u8 hash_new_inode[UBIFS_HASH_ARR_SZ];
1233        u8 hash_whiteout_inode[UBIFS_HASH_ARR_SZ];
1234        u8 hash_dent1[UBIFS_HASH_ARR_SZ];
1235        u8 hash_dent2[UBIFS_HASH_ARR_SZ];
1236
1237        ubifs_assert(c, ubifs_inode(old_dir)->data_len == 0);
1238        ubifs_assert(c, ubifs_inode(new_dir)->data_len == 0);
1239        ubifs_assert(c, mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
1240        ubifs_assert(c, mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
1241
1242        dlen1 = UBIFS_DENT_NODE_SZ + fname_len(new_nm) + 1;
1243        dlen2 = UBIFS_DENT_NODE_SZ + fname_len(old_nm) + 1;
1244        if (new_inode) {
1245                new_ui = ubifs_inode(new_inode);
1246                ubifs_assert(c, mutex_is_locked(&new_ui->ui_mutex));
1247                ilen = UBIFS_INO_NODE_SZ;
1248                if (!last_reference)
1249                        ilen += new_ui->data_len;
1250        } else
1251                ilen = 0;
1252
1253        if (whiteout) {
1254                whiteout_ui = ubifs_inode(whiteout);
1255                ubifs_assert(c, mutex_is_locked(&whiteout_ui->ui_mutex));
1256                ubifs_assert(c, whiteout->i_nlink == 1);
1257                ubifs_assert(c, !whiteout_ui->dirty);
1258                wlen = UBIFS_INO_NODE_SZ;
1259                wlen += whiteout_ui->data_len;
1260        } else
1261                wlen = 0;
1262
1263        aligned_dlen1 = ALIGN(dlen1, 8);
1264        aligned_dlen2 = ALIGN(dlen2, 8);
1265        len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) +
1266              ALIGN(wlen, 8) + ALIGN(plen, 8);
1267        if (move)
1268                len += plen;
1269
1270        len += ubifs_auth_node_sz(c);
1271
1272        dent = kzalloc(len, GFP_NOFS);
1273        if (!dent)
1274                return -ENOMEM;
1275
1276        /* Make reservation before allocating sequence numbers */
1277        err = make_reservation(c, BASEHD, len);
1278        if (err)
1279                goto out_free;
1280
1281        /* Make new dent */
1282        dent->ch.node_type = UBIFS_DENT_NODE;
1283        dent_key_init_flash(c, &dent->key, new_dir->i_ino, new_nm);
1284        dent->inum = cpu_to_le64(old_inode->i_ino);
1285        dent->type = get_dent_type(old_inode->i_mode);
1286        dent->nlen = cpu_to_le16(fname_len(new_nm));
1287        memcpy(dent->name, fname_name(new_nm), fname_len(new_nm));
1288        dent->name[fname_len(new_nm)] = '\0';
1289        set_dent_cookie(c, dent);
1290        zero_dent_node_unused(dent);
1291        ubifs_prep_grp_node(c, dent, dlen1, 0);
1292        err = ubifs_node_calc_hash(c, dent, hash_dent1);
1293        if (err)
1294                goto out_release;
1295
1296        dent2 = (void *)dent + aligned_dlen1;
1297        dent2->ch.node_type = UBIFS_DENT_NODE;
1298        dent_key_init_flash(c, &dent2->key, old_dir->i_ino, old_nm);
1299
1300        if (whiteout) {
1301                dent2->inum = cpu_to_le64(whiteout->i_ino);
1302                dent2->type = get_dent_type(whiteout->i_mode);
1303        } else {
1304                /* Make deletion dent */
1305                dent2->inum = 0;
1306                dent2->type = DT_UNKNOWN;
1307        }
1308        dent2->nlen = cpu_to_le16(fname_len(old_nm));
1309        memcpy(dent2->name, fname_name(old_nm), fname_len(old_nm));
1310        dent2->name[fname_len(old_nm)] = '\0';
1311        set_dent_cookie(c, dent2);
1312        zero_dent_node_unused(dent2);
1313        ubifs_prep_grp_node(c, dent2, dlen2, 0);
1314        err = ubifs_node_calc_hash(c, dent2, hash_dent2);
1315        if (err)
1316                goto out_release;
1317
1318        p = (void *)dent2 + aligned_dlen2;
1319        if (new_inode) {
1320                pack_inode(c, p, new_inode, 0);
1321                err = ubifs_node_calc_hash(c, p, hash_new_inode);
1322                if (err)
1323                        goto out_release;
1324
1325                p += ALIGN(ilen, 8);
1326        }
1327
1328        if (whiteout) {
1329                pack_inode(c, p, whiteout, 0);
1330                err = ubifs_node_calc_hash(c, p, hash_whiteout_inode);
1331                if (err)
1332                        goto out_release;
1333
1334                p += ALIGN(wlen, 8);
1335        }
1336
1337        if (!move) {
1338                pack_inode(c, p, old_dir, 1);
1339                err = ubifs_node_calc_hash(c, p, hash_old_dir);
1340                if (err)
1341                        goto out_release;
1342        } else {
1343                pack_inode(c, p, old_dir, 0);
1344                err = ubifs_node_calc_hash(c, p, hash_old_dir);
1345                if (err)
1346                        goto out_release;
1347
1348                p += ALIGN(plen, 8);
1349                pack_inode(c, p, new_dir, 1);
1350                err = ubifs_node_calc_hash(c, p, hash_new_dir);
1351                if (err)
1352                        goto out_release;
1353        }
1354
1355        if (last_reference) {
1356                err = ubifs_add_orphan(c, new_inode->i_ino);
1357                if (err) {
1358                        release_head(c, BASEHD);
1359                        goto out_finish;
1360                }
1361                new_ui->del_cmtno = c->cmt_no;
1362                orphan_added = 1;
1363        }
1364
1365        err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
1366        if (err)
1367                goto out_release;
1368        if (!sync) {
1369                struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1370
1371                ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
1372                ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
1373                if (new_inode)
1374                        ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
1375                                                  new_inode->i_ino);
1376                if (whiteout)
1377                        ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
1378                                                  whiteout->i_ino);
1379        }
1380        release_head(c, BASEHD);
1381
1382        ubifs_add_auth_dirt(c, lnum);
1383
1384        dent_key_init(c, &key, new_dir->i_ino, new_nm);
1385        err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, hash_dent1, new_nm);
1386        if (err)
1387                goto out_ro;
1388
1389        offs += aligned_dlen1;
1390        if (whiteout) {
1391                dent_key_init(c, &key, old_dir->i_ino, old_nm);
1392                err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen2, hash_dent2, old_nm);
1393                if (err)
1394                        goto out_ro;
1395        } else {
1396                err = ubifs_add_dirt(c, lnum, dlen2);
1397                if (err)
1398                        goto out_ro;
1399
1400                dent_key_init(c, &key, old_dir->i_ino, old_nm);
1401                err = ubifs_tnc_remove_nm(c, &key, old_nm);
1402                if (err)
1403                        goto out_ro;
1404        }
1405
1406        offs += aligned_dlen2;
1407        if (new_inode) {
1408                ino_key_init(c, &key, new_inode->i_ino);
1409                err = ubifs_tnc_add(c, &key, lnum, offs, ilen, hash_new_inode);
1410                if (err)
1411                        goto out_ro;
1412                offs += ALIGN(ilen, 8);
1413        }
1414
1415        if (whiteout) {
1416                ino_key_init(c, &key, whiteout->i_ino);
1417                err = ubifs_tnc_add(c, &key, lnum, offs, wlen,
1418                                    hash_whiteout_inode);
1419                if (err)
1420                        goto out_ro;
1421                offs += ALIGN(wlen, 8);
1422        }
1423
1424        ino_key_init(c, &key, old_dir->i_ino);
1425        err = ubifs_tnc_add(c, &key, lnum, offs, plen, hash_old_dir);
1426        if (err)
1427                goto out_ro;
1428
1429        if (move) {
1430                offs += ALIGN(plen, 8);
1431                ino_key_init(c, &key, new_dir->i_ino);
1432                err = ubifs_tnc_add(c, &key, lnum, offs, plen, hash_new_dir);
1433                if (err)
1434                        goto out_ro;
1435        }
1436
1437        finish_reservation(c);
1438        if (new_inode) {
1439                mark_inode_clean(c, new_ui);
1440                spin_lock(&new_ui->ui_lock);
1441                new_ui->synced_i_size = new_ui->ui_size;
1442                spin_unlock(&new_ui->ui_lock);
1443        }
1444        /*
1445         * No need to mark whiteout inode clean.
1446         * Whiteout doesn't have non-zero size, no need to update
1447         * synced_i_size for whiteout_ui.
1448         */
1449        mark_inode_clean(c, ubifs_inode(old_dir));
1450        if (move)
1451                mark_inode_clean(c, ubifs_inode(new_dir));
1452        kfree(dent);
1453        return 0;
1454
1455out_release:
1456        release_head(c, BASEHD);
1457out_ro:
1458        ubifs_ro_mode(c, err);
1459        if (orphan_added)
1460                ubifs_delete_orphan(c, new_inode->i_ino);
1461out_finish:
1462        finish_reservation(c);
1463out_free:
1464        kfree(dent);
1465        return err;
1466}
1467
1468/**
1469 * truncate_data_node - re-compress/encrypt a truncated data node.
1470 * @c: UBIFS file-system description object
1471 * @inode: inode which refers to the data node
1472 * @block: data block number
1473 * @dn: data node to re-compress
1474 * @new_len: new length
1475 *
1476 * This function is used when an inode is truncated and the last data node of
1477 * the inode has to be re-compressed/encrypted and re-written.
1478 */
1479static int truncate_data_node(const struct ubifs_info *c, const struct inode *inode,
1480                              unsigned int block, struct ubifs_data_node *dn,
1481                              int *new_len)
1482{
1483        void *buf;
1484        int err, dlen, compr_type, out_len, old_dlen;
1485
1486        out_len = le32_to_cpu(dn->size);
1487        buf = kmalloc_array(out_len, WORST_COMPR_FACTOR, GFP_NOFS);
1488        if (!buf)
1489                return -ENOMEM;
1490
1491        dlen = old_dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
1492        compr_type = le16_to_cpu(dn->compr_type);
1493
1494        if (IS_ENCRYPTED(inode)) {
1495                err = ubifs_decrypt(inode, dn, &dlen, block);
1496                if (err)
1497                        goto out;
1498        }
1499
1500        if (compr_type == UBIFS_COMPR_NONE) {
1501                out_len = *new_len;
1502        } else {
1503                err = ubifs_decompress(c, &dn->data, dlen, buf, &out_len, compr_type);
1504                if (err)
1505                        goto out;
1506
1507                ubifs_compress(c, buf, *new_len, &dn->data, &out_len, &compr_type);
1508        }
1509
1510        if (IS_ENCRYPTED(inode)) {
1511                err = ubifs_encrypt(inode, dn, out_len, &old_dlen, block);
1512                if (err)
1513                        goto out;
1514
1515                out_len = old_dlen;
1516        } else {
1517                dn->compr_size = 0;
1518        }
1519
1520        ubifs_assert(c, out_len <= UBIFS_BLOCK_SIZE);
1521        dn->compr_type = cpu_to_le16(compr_type);
1522        dn->size = cpu_to_le32(*new_len);
1523        *new_len = UBIFS_DATA_NODE_SZ + out_len;
1524        err = 0;
1525out:
1526        kfree(buf);
1527        return err;
1528}
1529
1530/**
1531 * ubifs_jnl_truncate - update the journal for a truncation.
1532 * @c: UBIFS file-system description object
1533 * @inode: inode to truncate
1534 * @old_size: old size
1535 * @new_size: new size
1536 *
1537 * When the size of a file decreases due to truncation, a truncation node is
1538 * written, the journal tree is updated, and the last data block is re-written
1539 * if it has been affected. The inode is also updated in order to synchronize
1540 * the new inode size.
1541 *
1542 * This function marks the inode as clean and returns zero on success. In case
1543 * of failure, a negative error code is returned.
1544 */
1545int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1546                       loff_t old_size, loff_t new_size)
1547{
1548        union ubifs_key key, to_key;
1549        struct ubifs_ino_node *ino;
1550        struct ubifs_trun_node *trun;
1551        struct ubifs_data_node *dn;
1552        int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
1553        struct ubifs_inode *ui = ubifs_inode(inode);
1554        ino_t inum = inode->i_ino;
1555        unsigned int blk;
1556        u8 hash_ino[UBIFS_HASH_ARR_SZ];
1557        u8 hash_dn[UBIFS_HASH_ARR_SZ];
1558
1559        dbg_jnl("ino %lu, size %lld -> %lld",
1560                (unsigned long)inum, old_size, new_size);
1561        ubifs_assert(c, !ui->data_len);
1562        ubifs_assert(c, S_ISREG(inode->i_mode));
1563        ubifs_assert(c, mutex_is_locked(&ui->ui_mutex));
1564
1565        sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
1566             UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
1567
1568        sz += ubifs_auth_node_sz(c);
1569
1570        ino = kmalloc(sz, GFP_NOFS);
1571        if (!ino)
1572                return -ENOMEM;
1573
1574        trun = (void *)ino + UBIFS_INO_NODE_SZ;
1575        trun->ch.node_type = UBIFS_TRUN_NODE;
1576        trun->inum = cpu_to_le32(inum);
1577        trun->old_size = cpu_to_le64(old_size);
1578        trun->new_size = cpu_to_le64(new_size);
1579        zero_trun_node_unused(trun);
1580
1581        dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
1582        if (dlen) {
1583                /* Get last data block so it can be truncated */
1584                dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
1585                blk = new_size >> UBIFS_BLOCK_SHIFT;
1586                data_key_init(c, &key, inum, blk);
1587                dbg_jnlk(&key, "last block key ");
1588                err = ubifs_tnc_lookup(c, &key, dn);
1589                if (err == -ENOENT)
1590                        dlen = 0; /* Not found (so it is a hole) */
1591                else if (err)
1592                        goto out_free;
1593                else {
1594                        int dn_len = le32_to_cpu(dn->size);
1595
1596                        if (dn_len <= 0 || dn_len > UBIFS_BLOCK_SIZE) {
1597                                ubifs_err(c, "bad data node (block %u, inode %lu)",
1598                                          blk, inode->i_ino);
1599                                ubifs_dump_node(c, dn, sz - UBIFS_INO_NODE_SZ -
1600                                                UBIFS_TRUN_NODE_SZ);
1601                                goto out_free;
1602                        }
1603
1604                        if (dn_len <= dlen)
1605                                dlen = 0; /* Nothing to do */
1606                        else {
1607                                err = truncate_data_node(c, inode, blk, dn, &dlen);
1608                                if (err)
1609                                        goto out_free;
1610                        }
1611                }
1612        }
1613
1614        /* Must make reservation before allocating sequence numbers */
1615        len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
1616
1617        if (ubifs_authenticated(c))
1618                len += ALIGN(dlen, 8) + ubifs_auth_node_sz(c);
1619        else
1620                len += dlen;
1621
1622        err = make_reservation(c, BASEHD, len);
1623        if (err)
1624                goto out_free;
1625
1626        pack_inode(c, ino, inode, 0);
1627        err = ubifs_node_calc_hash(c, ino, hash_ino);
1628        if (err)
1629                goto out_release;
1630
1631        ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
1632        if (dlen) {
1633                ubifs_prep_grp_node(c, dn, dlen, 1);
1634                err = ubifs_node_calc_hash(c, dn, hash_dn);
1635                if (err)
1636                        goto out_release;
1637        }
1638
1639        err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
1640        if (err)
1641                goto out_release;
1642        if (!sync)
1643                ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
1644        release_head(c, BASEHD);
1645
1646        ubifs_add_auth_dirt(c, lnum);
1647
1648        if (dlen) {
1649                sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
1650                err = ubifs_tnc_add(c, &key, lnum, sz, dlen, hash_dn);
1651                if (err)
1652                        goto out_ro;
1653        }
1654
1655        ino_key_init(c, &key, inum);
1656        err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ, hash_ino);
1657        if (err)
1658                goto out_ro;
1659
1660        err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
1661        if (err)
1662                goto out_ro;
1663
1664        bit = new_size & (UBIFS_BLOCK_SIZE - 1);
1665        blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
1666        data_key_init(c, &key, inum, blk);
1667
1668        bit = old_size & (UBIFS_BLOCK_SIZE - 1);
1669        blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0 : 1);
1670        data_key_init(c, &to_key, inum, blk);
1671
1672        err = ubifs_tnc_remove_range(c, &key, &to_key);
1673        if (err)
1674                goto out_ro;
1675
1676        finish_reservation(c);
1677        spin_lock(&ui->ui_lock);
1678        ui->synced_i_size = ui->ui_size;
1679        spin_unlock(&ui->ui_lock);
1680        mark_inode_clean(c, ui);
1681        kfree(ino);
1682        return 0;
1683
1684out_release:
1685        release_head(c, BASEHD);
1686out_ro:
1687        ubifs_ro_mode(c, err);
1688        finish_reservation(c);
1689out_free:
1690        kfree(ino);
1691        return err;
1692}
1693
1694
1695/**
1696 * ubifs_jnl_delete_xattr - delete an extended attribute.
1697 * @c: UBIFS file-system description object
1698 * @host: host inode
1699 * @inode: extended attribute inode
1700 * @nm: extended attribute entry name
1701 *
1702 * This function delete an extended attribute which is very similar to
1703 * un-linking regular files - it writes a deletion xentry, a deletion inode and
1704 * updates the target inode. Returns zero in case of success and a negative
1705 * error code in case of failure.
1706 */
1707int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1708                           const struct inode *inode,
1709                           const struct fscrypt_name *nm)
1710{
1711        int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen, write_len;
1712        struct ubifs_dent_node *xent;
1713        struct ubifs_ino_node *ino;
1714        union ubifs_key xent_key, key1, key2;
1715        int sync = IS_DIRSYNC(host);
1716        struct ubifs_inode *host_ui = ubifs_inode(host);
1717        u8 hash[UBIFS_HASH_ARR_SZ];
1718
1719        ubifs_assert(c, inode->i_nlink == 0);
1720        ubifs_assert(c, mutex_is_locked(&host_ui->ui_mutex));
1721
1722        /*
1723         * Since we are deleting the inode, we do not bother to attach any data
1724         * to it and assume its length is %UBIFS_INO_NODE_SZ.
1725         */
1726        xlen = UBIFS_DENT_NODE_SZ + fname_len(nm) + 1;
1727        aligned_xlen = ALIGN(xlen, 8);
1728        hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
1729        len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
1730
1731        write_len = len + ubifs_auth_node_sz(c);
1732
1733        xent = kzalloc(write_len, GFP_NOFS);
1734        if (!xent)
1735                return -ENOMEM;
1736
1737        /* Make reservation before allocating sequence numbers */
1738        err = make_reservation(c, BASEHD, write_len);
1739        if (err) {
1740                kfree(xent);
1741                return err;
1742        }
1743
1744        xent->ch.node_type = UBIFS_XENT_NODE;
1745        xent_key_init(c, &xent_key, host->i_ino, nm);
1746        key_write(c, &xent_key, xent->key);
1747        xent->inum = 0;
1748        xent->type = get_dent_type(inode->i_mode);
1749        xent->nlen = cpu_to_le16(fname_len(nm));
1750        memcpy(xent->name, fname_name(nm), fname_len(nm));
1751        xent->name[fname_len(nm)] = '\0';
1752        zero_dent_node_unused(xent);
1753        ubifs_prep_grp_node(c, xent, xlen, 0);
1754
1755        ino = (void *)xent + aligned_xlen;
1756        pack_inode(c, ino, inode, 0);
1757        ino = (void *)ino + UBIFS_INO_NODE_SZ;
1758        pack_inode(c, ino, host, 1);
1759        err = ubifs_node_calc_hash(c, ino, hash);
1760        if (err)
1761                goto out_release;
1762
1763        err = write_head(c, BASEHD, xent, write_len, &lnum, &xent_offs, sync);
1764        if (!sync && !err)
1765                ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
1766        release_head(c, BASEHD);
1767
1768        ubifs_add_auth_dirt(c, lnum);
1769        kfree(xent);
1770        if (err)
1771                goto out_ro;
1772
1773        /* Remove the extended attribute entry from TNC */
1774        err = ubifs_tnc_remove_nm(c, &xent_key, nm);
1775        if (err)
1776                goto out_ro;
1777        err = ubifs_add_dirt(c, lnum, xlen);
1778        if (err)
1779                goto out_ro;
1780
1781        /*
1782         * Remove all nodes belonging to the extended attribute inode from TNC.
1783         * Well, there actually must be only one node - the inode itself.
1784         */
1785        lowest_ino_key(c, &key1, inode->i_ino);
1786        highest_ino_key(c, &key2, inode->i_ino);
1787        err = ubifs_tnc_remove_range(c, &key1, &key2);
1788        if (err)
1789                goto out_ro;
1790        err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
1791        if (err)
1792                goto out_ro;
1793
1794        /* And update TNC with the new host inode position */
1795        ino_key_init(c, &key1, host->i_ino);
1796        err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen, hash);
1797        if (err)
1798                goto out_ro;
1799
1800        finish_reservation(c);
1801        spin_lock(&host_ui->ui_lock);
1802        host_ui->synced_i_size = host_ui->ui_size;
1803        spin_unlock(&host_ui->ui_lock);
1804        mark_inode_clean(c, host_ui);
1805        return 0;
1806
1807out_release:
1808        kfree(xent);
1809        release_head(c, BASEHD);
1810out_ro:
1811        ubifs_ro_mode(c, err);
1812        finish_reservation(c);
1813        return err;
1814}
1815
1816/**
1817 * ubifs_jnl_change_xattr - change an extended attribute.
1818 * @c: UBIFS file-system description object
1819 * @inode: extended attribute inode
1820 * @host: host inode
1821 *
1822 * This function writes the updated version of an extended attribute inode and
1823 * the host inode to the journal (to the base head). The host inode is written
1824 * after the extended attribute inode in order to guarantee that the extended
1825 * attribute will be flushed when the inode is synchronized by 'fsync()' and
1826 * consequently, the write-buffer is synchronized. This function returns zero
1827 * in case of success and a negative error code in case of failure.
1828 */
1829int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
1830                           const struct inode *host)
1831{
1832        int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
1833        struct ubifs_inode *host_ui = ubifs_inode(host);
1834        struct ubifs_ino_node *ino;
1835        union ubifs_key key;
1836        int sync = IS_DIRSYNC(host);
1837        u8 hash_host[UBIFS_HASH_ARR_SZ];
1838        u8 hash[UBIFS_HASH_ARR_SZ];
1839
1840        dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
1841        ubifs_assert(c, inode->i_nlink > 0);
1842        ubifs_assert(c, mutex_is_locked(&host_ui->ui_mutex));
1843
1844        len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
1845        len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
1846        aligned_len1 = ALIGN(len1, 8);
1847        aligned_len = aligned_len1 + ALIGN(len2, 8);
1848
1849        aligned_len += ubifs_auth_node_sz(c);
1850
1851        ino = kzalloc(aligned_len, GFP_NOFS);
1852        if (!ino)
1853                return -ENOMEM;
1854
1855        /* Make reservation before allocating sequence numbers */
1856        err = make_reservation(c, BASEHD, aligned_len);
1857        if (err)
1858                goto out_free;
1859
1860        pack_inode(c, ino, host, 0);
1861        err = ubifs_node_calc_hash(c, ino, hash_host);
1862        if (err)
1863                goto out_release;
1864        pack_inode(c, (void *)ino + aligned_len1, inode, 1);
1865        err = ubifs_node_calc_hash(c, (void *)ino + aligned_len1, hash);
1866        if (err)
1867                goto out_release;
1868
1869        err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
1870        if (!sync && !err) {
1871                struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1872
1873                ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
1874                ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
1875        }
1876        release_head(c, BASEHD);
1877        if (err)
1878                goto out_ro;
1879
1880        ubifs_add_auth_dirt(c, lnum);
1881
1882        ino_key_init(c, &key, host->i_ino);
1883        err = ubifs_tnc_add(c, &key, lnum, offs, len1, hash_host);
1884        if (err)
1885                goto out_ro;
1886
1887        ino_key_init(c, &key, inode->i_ino);
1888        err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2, hash);
1889        if (err)
1890                goto out_ro;
1891
1892        finish_reservation(c);
1893        spin_lock(&host_ui->ui_lock);
1894        host_ui->synced_i_size = host_ui->ui_size;
1895        spin_unlock(&host_ui->ui_lock);
1896        mark_inode_clean(c, host_ui);
1897        kfree(ino);
1898        return 0;
1899
1900out_release:
1901        release_head(c, BASEHD);
1902out_ro:
1903        ubifs_ro_mode(c, err);
1904        finish_reservation(c);
1905out_free:
1906        kfree(ino);
1907        return err;
1908}
1909
1910