linux/fs/ubifs/journal.c
<<
>>
Prefs
   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 */
  67static 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 */
  78static inline void zero_dent_node_unused(struct ubifs_dent_node *dent)
  79{
  80        dent->padding1 = 0;
  81        memset(dent->padding2, 0, 4);
  82}
  83
  84/**
  85 * zero_data_node_unused - zero out unused fields of an on-flash data node.
  86 * @data: the data node to zero out
  87 */
  88static inline void zero_data_node_unused(struct ubifs_data_node *data)
  89{
  90        memset(data->padding, 0, 2);
  91}
  92
  93/**
  94 * zero_trun_node_unused - zero out unused fields of an on-flash truncation
  95 *                         node.
  96 * @trun: the truncation node to zero out
  97 */
  98static inline void zero_trun_node_unused(struct ubifs_trun_node *trun)
  99{
 100        memset(trun->padding, 0, 12);
 101}
 102
 103/**
 104 * reserve_space - reserve space in the journal.
 105 * @c: UBIFS file-system description object
 106 * @jhead: journal head number
 107 * @len: node length
 108 *
 109 * This function reserves space in journal head @head. If the reservation
 110 * succeeded, the journal head stays locked and later has to be unlocked using
 111 * 'release_head()'. 'write_node()' and 'write_head()' functions also unlock
 112 * it. Returns zero in case of success, %-EAGAIN if commit has to be done, and
 113 * other negative error codes in case of other failures.
 114 */
 115static int reserve_space(struct ubifs_info *c, int jhead, int len)
 116{
 117        int err = 0, err1, retries = 0, avail, lnum, offs, squeeze;
 118        struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 119
 120        /*
 121         * Typically, the base head has smaller nodes written to it, so it is
 122         * better to try to allocate space at the ends of eraseblocks. This is
 123         * what the squeeze parameter does.
 124         */
 125        ubifs_assert(!c->ro_media && !c->ro_mount);
 126        squeeze = (jhead == BASEHD);
 127again:
 128        mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 129
 130        if (c->ro_error) {
 131                err = -EROFS;
 132                goto out_unlock;
 133        }
 134
 135        avail = c->leb_size - wbuf->offs - wbuf->used;
 136        if (wbuf->lnum != -1 && avail >= len)
 137                return 0;
 138
 139        /*
 140         * Write buffer wasn't seek'ed or there is no enough space - look for an
 141         * LEB with some empty space.
 142         */
 143        lnum = ubifs_find_free_space(c, len, &offs, squeeze);
 144        if (lnum >= 0)
 145                goto out;
 146
 147        err = lnum;
 148        if (err != -ENOSPC)
 149                goto out_unlock;
 150
 151        /*
 152         * No free space, we have to run garbage collector to make
 153         * some. But the write-buffer mutex has to be unlocked because
 154         * GC also takes it.
 155         */
 156        dbg_jnl("no free space in jhead %s, run GC", dbg_jhead(jhead));
 157        mutex_unlock(&wbuf->io_mutex);
 158
 159        lnum = ubifs_garbage_collect(c, 0);
 160        if (lnum < 0) {
 161                err = lnum;
 162                if (err != -ENOSPC)
 163                        return err;
 164
 165                /*
 166                 * GC could not make a free LEB. But someone else may
 167                 * have allocated new bud for this journal head,
 168                 * because we dropped @wbuf->io_mutex, so try once
 169                 * again.
 170                 */
 171                dbg_jnl("GC couldn't make a free LEB for jhead %s",
 172                        dbg_jhead(jhead));
 173                if (retries++ < 2) {
 174                        dbg_jnl("retry (%d)", retries);
 175                        goto again;
 176                }
 177
 178                dbg_jnl("return -ENOSPC");
 179                return err;
 180        }
 181
 182        mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
 183        dbg_jnl("got LEB %d for jhead %s", lnum, dbg_jhead(jhead));
 184        avail = c->leb_size - wbuf->offs - wbuf->used;
 185
 186        if (wbuf->lnum != -1 && avail >= len) {
 187                /*
 188                 * Someone else has switched the journal head and we have
 189                 * enough space now. This happens when more than one process is
 190                 * trying to write to the same journal head at the same time.
 191                 */
 192                dbg_jnl("return LEB %d back, already have LEB %d:%d",
 193                        lnum, wbuf->lnum, wbuf->offs + wbuf->used);
 194                err = ubifs_return_leb(c, lnum);
 195                if (err)
 196                        goto out_unlock;
 197                return 0;
 198        }
 199
 200        offs = 0;
 201
 202out:
 203        /*
 204         * Make sure we synchronize the write-buffer before we add the new bud
 205         * to the log. Otherwise we may have a power cut after the log
 206         * reference node for the last bud (@lnum) is written but before the
 207         * write-buffer data are written to the next-to-last bud
 208         * (@wbuf->lnum). And the effect would be that the recovery would see
 209         * that there is corruption in the next-to-last bud.
 210         */
 211        err = ubifs_wbuf_sync_nolock(wbuf);
 212        if (err)
 213                goto out_return;
 214        err = ubifs_add_bud_to_log(c, jhead, lnum, offs);
 215        if (err)
 216                goto out_return;
 217        err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs);
 218        if (err)
 219                goto out_unlock;
 220
 221        return 0;
 222
 223out_unlock:
 224        mutex_unlock(&wbuf->io_mutex);
 225        return err;
 226
 227out_return:
 228        /* An error occurred and the LEB has to be returned to lprops */
 229        ubifs_assert(err < 0);
 230        err1 = ubifs_return_leb(c, lnum);
 231        if (err1 && err == -EAGAIN)
 232                /*
 233                 * Return original error code only if it is not %-EAGAIN,
 234                 * which is not really an error. Otherwise, return the error
 235                 * code of 'ubifs_return_leb()'.
 236                 */
 237                err = err1;
 238        mutex_unlock(&wbuf->io_mutex);
 239        return err;
 240}
 241
 242/**
 243 * write_node - write node to a journal head.
 244 * @c: UBIFS file-system description object
 245 * @jhead: journal head
 246 * @node: node to write
 247 * @len: node length
 248 * @lnum: LEB number written is returned here
 249 * @offs: offset written is returned here
 250 *
 251 * This function writes a node to reserved space of journal head @jhead.
 252 * Returns zero in case of success and a negative error code in case of
 253 * failure.
 254 */
 255static int write_node(struct ubifs_info *c, int jhead, void *node, int len,
 256                      int *lnum, int *offs)
 257{
 258        struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 259
 260        ubifs_assert(jhead != GCHD);
 261
 262        *lnum = c->jheads[jhead].wbuf.lnum;
 263        *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 264
 265        dbg_jnl("jhead %s, LEB %d:%d, len %d",
 266                dbg_jhead(jhead), *lnum, *offs, len);
 267        ubifs_prepare_node(c, node, len, 0);
 268
 269        return ubifs_wbuf_write_nolock(wbuf, node, len);
 270}
 271
 272/**
 273 * write_head - write data to a journal head.
 274 * @c: UBIFS file-system description object
 275 * @jhead: journal head
 276 * @buf: buffer to write
 277 * @len: length to write
 278 * @lnum: LEB number written is returned here
 279 * @offs: offset written is returned here
 280 * @sync: non-zero if the write-buffer has to by synchronized
 281 *
 282 * This function is the same as 'write_node()' but it does not assume the
 283 * buffer it is writing is a node, so it does not prepare it (which means
 284 * initializing common header and calculating CRC).
 285 */
 286static int write_head(struct ubifs_info *c, int jhead, void *buf, int len,
 287                      int *lnum, int *offs, int sync)
 288{
 289        int err;
 290        struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf;
 291
 292        ubifs_assert(jhead != GCHD);
 293
 294        *lnum = c->jheads[jhead].wbuf.lnum;
 295        *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used;
 296        dbg_jnl("jhead %s, LEB %d:%d, len %d",
 297                dbg_jhead(jhead), *lnum, *offs, len);
 298
 299        err = ubifs_wbuf_write_nolock(wbuf, buf, len);
 300        if (err)
 301                return err;
 302        if (sync)
 303                err = ubifs_wbuf_sync_nolock(wbuf);
 304        return err;
 305}
 306
 307/**
 308 * make_reservation - reserve journal space.
 309 * @c: UBIFS file-system description object
 310 * @jhead: journal head
 311 * @len: how many bytes to reserve
 312 *
 313 * This function makes space reservation in journal head @jhead. The function
 314 * takes the commit lock and locks the journal head, and the caller has to
 315 * unlock the head and finish the reservation with 'finish_reservation()'.
 316 * Returns zero in case of success and a negative error code in case of
 317 * failure.
 318 *
 319 * Note, the journal head may be unlocked as soon as the data is written, while
 320 * the commit lock has to be released after the data has been added to the
 321 * TNC.
 322 */
 323static int make_reservation(struct ubifs_info *c, int jhead, int len)
 324{
 325        int err, cmt_retries = 0, nospc_retries = 0;
 326
 327again:
 328        down_read(&c->commit_sem);
 329        err = reserve_space(c, jhead, len);
 330        if (!err)
 331                return 0;
 332        up_read(&c->commit_sem);
 333
 334        if (err == -ENOSPC) {
 335                /*
 336                 * GC could not make any progress. We should try to commit
 337                 * once because it could make some dirty space and GC would
 338                 * make progress, so make the error -EAGAIN so that the below
 339                 * will commit and re-try.
 340                 */
 341                if (nospc_retries++ < 2) {
 342                        dbg_jnl("no space, retry");
 343                        err = -EAGAIN;
 344                }
 345
 346                /*
 347                 * This means that the budgeting is incorrect. We always have
 348                 * to be able to write to the media, because all operations are
 349                 * budgeted. Deletions are not budgeted, though, but we reserve
 350                 * an extra LEB for them.
 351                 */
 352        }
 353
 354        if (err != -EAGAIN)
 355                goto out;
 356
 357        /*
 358         * -EAGAIN means that the journal is full or too large, or the above
 359         * code wants to do one commit. Do this and re-try.
 360         */
 361        if (cmt_retries > 128) {
 362                /*
 363                 * This should not happen unless the journal size limitations
 364                 * are too tough.
 365                 */
 366                ubifs_err("stuck in space allocation");
 367                err = -ENOSPC;
 368                goto out;
 369        } else if (cmt_retries > 32)
 370                ubifs_warn("too many space allocation re-tries (%d)",
 371                           cmt_retries);
 372
 373        dbg_jnl("-EAGAIN, commit and retry (retried %d times)",
 374                cmt_retries);
 375        cmt_retries += 1;
 376
 377        err = ubifs_run_commit(c);
 378        if (err)
 379                return err;
 380        goto again;
 381
 382out:
 383        ubifs_err("cannot reserve %d bytes in jhead %d, error %d",
 384                  len, jhead, err);
 385        if (err == -ENOSPC) {
 386                /* This are some budgeting problems, print useful information */
 387                down_write(&c->commit_sem);
 388                dump_stack();
 389                ubifs_dump_budg(c, &c->bi);
 390                ubifs_dump_lprops(c);
 391                cmt_retries = dbg_check_lprops(c);
 392                up_write(&c->commit_sem);
 393        }
 394        return err;
 395}
 396
 397/**
 398 * release_head - release a journal head.
 399 * @c: UBIFS file-system description object
 400 * @jhead: journal head
 401 *
 402 * This function releases journal head @jhead which was locked by
 403 * the 'make_reservation()' function. It has to be called after each successful
 404 * 'make_reservation()' invocation.
 405 */
 406static inline void release_head(struct ubifs_info *c, int jhead)
 407{
 408        mutex_unlock(&c->jheads[jhead].wbuf.io_mutex);
 409}
 410
 411/**
 412 * finish_reservation - finish a reservation.
 413 * @c: UBIFS file-system description object
 414 *
 415 * This function finishes journal space reservation. It must be called after
 416 * 'make_reservation()'.
 417 */
 418static void finish_reservation(struct ubifs_info *c)
 419{
 420        up_read(&c->commit_sem);
 421}
 422
 423/**
 424 * get_dent_type - translate VFS inode mode to UBIFS directory entry type.
 425 * @mode: inode mode
 426 */
 427static int get_dent_type(int mode)
 428{
 429        switch (mode & S_IFMT) {
 430        case S_IFREG:
 431                return UBIFS_ITYPE_REG;
 432        case S_IFDIR:
 433                return UBIFS_ITYPE_DIR;
 434        case S_IFLNK:
 435                return UBIFS_ITYPE_LNK;
 436        case S_IFBLK:
 437                return UBIFS_ITYPE_BLK;
 438        case S_IFCHR:
 439                return UBIFS_ITYPE_CHR;
 440        case S_IFIFO:
 441                return UBIFS_ITYPE_FIFO;
 442        case S_IFSOCK:
 443                return UBIFS_ITYPE_SOCK;
 444        default:
 445                BUG();
 446        }
 447        return 0;
 448}
 449
 450/**
 451 * pack_inode - pack an inode node.
 452 * @c: UBIFS file-system description object
 453 * @ino: buffer in which to pack inode node
 454 * @inode: inode to pack
 455 * @last: indicates the last node of the group
 456 */
 457static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino,
 458                       const struct inode *inode, int last)
 459{
 460        int data_len = 0, last_reference = !inode->i_nlink;
 461        struct ubifs_inode *ui = ubifs_inode(inode);
 462
 463        ino->ch.node_type = UBIFS_INO_NODE;
 464        ino_key_init_flash(c, &ino->key, inode->i_ino);
 465        ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum);
 466        ino->atime_sec  = cpu_to_le64(inode->i_atime.tv_sec);
 467        ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
 468        ino->ctime_sec  = cpu_to_le64(inode->i_ctime.tv_sec);
 469        ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 470        ino->mtime_sec  = cpu_to_le64(inode->i_mtime.tv_sec);
 471        ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 472        ino->uid   = cpu_to_le32(inode->i_uid);
 473        ino->gid   = cpu_to_le32(inode->i_gid);
 474        ino->mode  = cpu_to_le32(inode->i_mode);
 475        ino->flags = cpu_to_le32(ui->flags);
 476        ino->size  = cpu_to_le64(ui->ui_size);
 477        ino->nlink = cpu_to_le32(inode->i_nlink);
 478        ino->compr_type  = cpu_to_le16(ui->compr_type);
 479        ino->data_len    = cpu_to_le32(ui->data_len);
 480        ino->xattr_cnt   = cpu_to_le32(ui->xattr_cnt);
 481        ino->xattr_size  = cpu_to_le32(ui->xattr_size);
 482        ino->xattr_names = cpu_to_le32(ui->xattr_names);
 483        zero_ino_node_unused(ino);
 484
 485        /*
 486         * Drop the attached data if this is a deletion inode, the data is not
 487         * needed anymore.
 488         */
 489        if (!last_reference) {
 490                memcpy(ino->data, ui->data, ui->data_len);
 491                data_len = ui->data_len;
 492        }
 493
 494        ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last);
 495}
 496
 497/**
 498 * mark_inode_clean - mark UBIFS inode as clean.
 499 * @c: UBIFS file-system description object
 500 * @ui: UBIFS inode to mark as clean
 501 *
 502 * This helper function marks UBIFS inode @ui as clean by cleaning the
 503 * @ui->dirty flag and releasing its budget. Note, VFS may still treat the
 504 * inode as dirty and try to write it back, but 'ubifs_write_inode()' would
 505 * just do nothing.
 506 */
 507static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui)
 508{
 509        if (ui->dirty)
 510                ubifs_release_dirty_inode_budget(c, ui);
 511        ui->dirty = 0;
 512}
 513
 514/**
 515 * ubifs_jnl_update - update inode.
 516 * @c: UBIFS file-system description object
 517 * @dir: parent inode or host inode in case of extended attributes
 518 * @nm: directory entry name
 519 * @inode: inode to update
 520 * @deletion: indicates a directory entry deletion i.e unlink or rmdir
 521 * @xent: non-zero if the directory entry is an extended attribute entry
 522 *
 523 * This function updates an inode by writing a directory entry (or extended
 524 * attribute entry), the inode itself, and the parent directory inode (or the
 525 * host inode) to the journal.
 526 *
 527 * The function writes the host inode @dir last, which is important in case of
 528 * extended attributes. Indeed, then we guarantee that if the host inode gets
 529 * synchronized (with 'fsync()'), and the write-buffer it sits in gets flushed,
 530 * the extended attribute inode gets flushed too. And this is exactly what the
 531 * user expects - synchronizing the host inode synchronizes its extended
 532 * attributes. Similarly, this guarantees that if @dir is synchronized, its
 533 * directory entry corresponding to @nm gets synchronized too.
 534 *
 535 * If the inode (@inode) or the parent directory (@dir) are synchronous, this
 536 * function synchronizes the write-buffer.
 537 *
 538 * This function marks the @dir and @inode inodes as clean and returns zero on
 539 * success. In case of failure, a negative error code is returned.
 540 */
 541int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
 542                     const struct qstr *nm, const struct inode *inode,
 543                     int deletion, int xent)
 544{
 545        int err, dlen, ilen, len, lnum, ino_offs, dent_offs;
 546        int aligned_dlen, aligned_ilen, sync = IS_DIRSYNC(dir);
 547        int last_reference = !!(deletion && inode->i_nlink == 0);
 548        struct ubifs_inode *ui = ubifs_inode(inode);
 549        struct ubifs_inode *dir_ui = ubifs_inode(dir);
 550        struct ubifs_dent_node *dent;
 551        struct ubifs_ino_node *ino;
 552        union ubifs_key dent_key, ino_key;
 553
 554        dbg_jnl("ino %lu, dent '%.*s', data len %d in dir ino %lu",
 555                inode->i_ino, nm->len, nm->name, ui->data_len, dir->i_ino);
 556        ubifs_assert(dir_ui->data_len == 0);
 557        ubifs_assert(mutex_is_locked(&dir_ui->ui_mutex));
 558
 559        dlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
 560        ilen = UBIFS_INO_NODE_SZ;
 561
 562        /*
 563         * If the last reference to the inode is being deleted, then there is
 564         * no need to attach and write inode data, it is being deleted anyway.
 565         * And if the inode is being deleted, no need to synchronize
 566         * write-buffer even if the inode is synchronous.
 567         */
 568        if (!last_reference) {
 569                ilen += ui->data_len;
 570                sync |= IS_SYNC(inode);
 571        }
 572
 573        aligned_dlen = ALIGN(dlen, 8);
 574        aligned_ilen = ALIGN(ilen, 8);
 575        len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ;
 576        dent = kmalloc(len, GFP_NOFS);
 577        if (!dent)
 578                return -ENOMEM;
 579
 580        /* Make reservation before allocating sequence numbers */
 581        err = make_reservation(c, BASEHD, len);
 582        if (err)
 583                goto out_free;
 584
 585        if (!xent) {
 586                dent->ch.node_type = UBIFS_DENT_NODE;
 587                dent_key_init(c, &dent_key, dir->i_ino, nm);
 588        } else {
 589                dent->ch.node_type = UBIFS_XENT_NODE;
 590                xent_key_init(c, &dent_key, dir->i_ino, nm);
 591        }
 592
 593        key_write(c, &dent_key, dent->key);
 594        dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino);
 595        dent->type = get_dent_type(inode->i_mode);
 596        dent->nlen = cpu_to_le16(nm->len);
 597        memcpy(dent->name, nm->name, nm->len);
 598        dent->name[nm->len] = '\0';
 599        zero_dent_node_unused(dent);
 600        ubifs_prep_grp_node(c, dent, dlen, 0);
 601
 602        ino = (void *)dent + aligned_dlen;
 603        pack_inode(c, ino, inode, 0);
 604        ino = (void *)ino + aligned_ilen;
 605        pack_inode(c, ino, dir, 1);
 606
 607        if (last_reference) {
 608                err = ubifs_add_orphan(c, inode->i_ino);
 609                if (err) {
 610                        release_head(c, BASEHD);
 611                        goto out_finish;
 612                }
 613                ui->del_cmtno = c->cmt_no;
 614        }
 615
 616        err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync);
 617        if (err)
 618                goto out_release;
 619        if (!sync) {
 620                struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
 621
 622                ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
 623                ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino);
 624        }
 625        release_head(c, BASEHD);
 626        kfree(dent);
 627
 628        if (deletion) {
 629                err = ubifs_tnc_remove_nm(c, &dent_key, nm);
 630                if (err)
 631                        goto out_ro;
 632                err = ubifs_add_dirt(c, lnum, dlen);
 633        } else
 634                err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm);
 635        if (err)
 636                goto out_ro;
 637
 638        /*
 639         * Note, we do not remove the inode from TNC even if the last reference
 640         * to it has just been deleted, because the inode may still be opened.
 641         * Instead, the inode has been added to orphan lists and the orphan
 642         * subsystem will take further care about it.
 643         */
 644        ino_key_init(c, &ino_key, inode->i_ino);
 645        ino_offs = dent_offs + aligned_dlen;
 646        err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen);
 647        if (err)
 648                goto out_ro;
 649
 650        ino_key_init(c, &ino_key, dir->i_ino);
 651        ino_offs += aligned_ilen;
 652        err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ);
 653        if (err)
 654                goto out_ro;
 655
 656        finish_reservation(c);
 657        spin_lock(&ui->ui_lock);
 658        ui->synced_i_size = ui->ui_size;
 659        spin_unlock(&ui->ui_lock);
 660        mark_inode_clean(c, ui);
 661        mark_inode_clean(c, dir_ui);
 662        return 0;
 663
 664out_finish:
 665        finish_reservation(c);
 666out_free:
 667        kfree(dent);
 668        return err;
 669
 670out_release:
 671        release_head(c, BASEHD);
 672        kfree(dent);
 673out_ro:
 674        ubifs_ro_mode(c, err);
 675        if (last_reference)
 676                ubifs_delete_orphan(c, inode->i_ino);
 677        finish_reservation(c);
 678        return err;
 679}
 680
 681/**
 682 * ubifs_jnl_write_data - write a data node to the journal.
 683 * @c: UBIFS file-system description object
 684 * @inode: inode the data node belongs to
 685 * @key: node key
 686 * @buf: buffer to write
 687 * @len: data length (must not exceed %UBIFS_BLOCK_SIZE)
 688 *
 689 * This function writes a data node to the journal. Returns %0 if the data node
 690 * was successfully written, and a negative error code in case of failure.
 691 */
 692int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode,
 693                         const union ubifs_key *key, const void *buf, int len)
 694{
 695        struct ubifs_data_node *data;
 696        int err, lnum, offs, compr_type, out_len;
 697        int dlen = COMPRESSED_DATA_NODE_BUF_SZ, allocated = 1;
 698        struct ubifs_inode *ui = ubifs_inode(inode);
 699
 700        dbg_jnlk(key, "ino %lu, blk %u, len %d, key ",
 701                (unsigned long)key_inum(c, key), key_block(c, key), len);
 702        ubifs_assert(len <= UBIFS_BLOCK_SIZE);
 703
 704        data = kmalloc(dlen, GFP_NOFS | __GFP_NOWARN);
 705        if (!data) {
 706                /*
 707                 * Fall-back to the write reserve buffer. Note, we might be
 708                 * currently on the memory reclaim path, when the kernel is
 709                 * trying to free some memory by writing out dirty pages. The
 710                 * write reserve buffer helps us to guarantee that we are
 711                 * always able to write the data.
 712                 */
 713                allocated = 0;
 714                mutex_lock(&c->write_reserve_mutex);
 715                data = c->write_reserve_buf;
 716        }
 717
 718        data->ch.node_type = UBIFS_DATA_NODE;
 719        key_write(c, key, &data->key);
 720        data->size = cpu_to_le32(len);
 721        zero_data_node_unused(data);
 722
 723        if (!(ui->flags & UBIFS_COMPR_FL))
 724                /* Compression is disabled for this inode */
 725                compr_type = UBIFS_COMPR_NONE;
 726        else
 727                compr_type = ui->compr_type;
 728
 729        out_len = dlen - UBIFS_DATA_NODE_SZ;
 730        ubifs_compress(buf, len, &data->data, &out_len, &compr_type);
 731        ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
 732
 733        dlen = UBIFS_DATA_NODE_SZ + out_len;
 734        data->compr_type = cpu_to_le16(compr_type);
 735
 736        /* Make reservation before allocating sequence numbers */
 737        err = make_reservation(c, DATAHD, dlen);
 738        if (err)
 739                goto out_free;
 740
 741        err = write_node(c, DATAHD, data, dlen, &lnum, &offs);
 742        if (err)
 743                goto out_release;
 744        ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key));
 745        release_head(c, DATAHD);
 746
 747        err = ubifs_tnc_add(c, key, lnum, offs, dlen);
 748        if (err)
 749                goto out_ro;
 750
 751        finish_reservation(c);
 752        if (!allocated)
 753                mutex_unlock(&c->write_reserve_mutex);
 754        else
 755                kfree(data);
 756        return 0;
 757
 758out_release:
 759        release_head(c, DATAHD);
 760out_ro:
 761        ubifs_ro_mode(c, err);
 762        finish_reservation(c);
 763out_free:
 764        if (!allocated)
 765                mutex_unlock(&c->write_reserve_mutex);
 766        else
 767                kfree(data);
 768        return err;
 769}
 770
 771/**
 772 * ubifs_jnl_write_inode - flush inode to the journal.
 773 * @c: UBIFS file-system description object
 774 * @inode: inode to flush
 775 *
 776 * This function writes inode @inode to the journal. If the inode is
 777 * synchronous, it also synchronizes the write-buffer. Returns zero in case of
 778 * success and a negative error code in case of failure.
 779 */
 780int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode)
 781{
 782        int err, lnum, offs;
 783        struct ubifs_ino_node *ino;
 784        struct ubifs_inode *ui = ubifs_inode(inode);
 785        int sync = 0, len = UBIFS_INO_NODE_SZ, last_reference = !inode->i_nlink;
 786
 787        dbg_jnl("ino %lu, nlink %u", inode->i_ino, inode->i_nlink);
 788
 789        /*
 790         * If the inode is being deleted, do not write the attached data. No
 791         * need to synchronize the write-buffer either.
 792         */
 793        if (!last_reference) {
 794                len += ui->data_len;
 795                sync = IS_SYNC(inode);
 796        }
 797        ino = kmalloc(len, GFP_NOFS);
 798        if (!ino)
 799                return -ENOMEM;
 800
 801        /* Make reservation before allocating sequence numbers */
 802        err = make_reservation(c, BASEHD, len);
 803        if (err)
 804                goto out_free;
 805
 806        pack_inode(c, ino, inode, 1);
 807        err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
 808        if (err)
 809                goto out_release;
 810        if (!sync)
 811                ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
 812                                          inode->i_ino);
 813        release_head(c, BASEHD);
 814
 815        if (last_reference) {
 816                err = ubifs_tnc_remove_ino(c, inode->i_ino);
 817                if (err)
 818                        goto out_ro;
 819                ubifs_delete_orphan(c, inode->i_ino);
 820                err = ubifs_add_dirt(c, lnum, len);
 821        } else {
 822                union ubifs_key key;
 823
 824                ino_key_init(c, &key, inode->i_ino);
 825                err = ubifs_tnc_add(c, &key, lnum, offs, len);
 826        }
 827        if (err)
 828                goto out_ro;
 829
 830        finish_reservation(c);
 831        spin_lock(&ui->ui_lock);
 832        ui->synced_i_size = ui->ui_size;
 833        spin_unlock(&ui->ui_lock);
 834        kfree(ino);
 835        return 0;
 836
 837out_release:
 838        release_head(c, BASEHD);
 839out_ro:
 840        ubifs_ro_mode(c, err);
 841        finish_reservation(c);
 842out_free:
 843        kfree(ino);
 844        return err;
 845}
 846
 847/**
 848 * ubifs_jnl_delete_inode - delete an inode.
 849 * @c: UBIFS file-system description object
 850 * @inode: inode to delete
 851 *
 852 * This function deletes inode @inode which includes removing it from orphans,
 853 * deleting it from TNC and, in some cases, writing a deletion inode to the
 854 * journal.
 855 *
 856 * When regular file inodes are unlinked or a directory inode is removed, the
 857 * 'ubifs_jnl_update()' function writes a corresponding deletion inode and
 858 * direntry to the media, and adds the inode to orphans. After this, when the
 859 * last reference to this inode has been dropped, this function is called. In
 860 * general, it has to write one more deletion inode to the media, because if
 861 * a commit happened between 'ubifs_jnl_update()' and
 862 * 'ubifs_jnl_delete_inode()', the deletion inode is not in the journal
 863 * anymore, and in fact it might not be on the flash anymore, because it might
 864 * have been garbage-collected already. And for optimization reasons UBIFS does
 865 * not read the orphan area if it has been unmounted cleanly, so it would have
 866 * no indication in the journal that there is a deleted inode which has to be
 867 * removed from TNC.
 868 *
 869 * However, if there was no commit between 'ubifs_jnl_update()' and
 870 * 'ubifs_jnl_delete_inode()', then there is no need to write the deletion
 871 * inode to the media for the second time. And this is quite a typical case.
 872 *
 873 * This function returns zero in case of success and a negative error code in
 874 * case of failure.
 875 */
 876int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode)
 877{
 878        int err;
 879        struct ubifs_inode *ui = ubifs_inode(inode);
 880
 881        ubifs_assert(inode->i_nlink == 0);
 882
 883        if (ui->del_cmtno != c->cmt_no)
 884                /* A commit happened for sure */
 885                return ubifs_jnl_write_inode(c, inode);
 886
 887        down_read(&c->commit_sem);
 888        /*
 889         * Check commit number again, because the first test has been done
 890         * without @c->commit_sem, so a commit might have happened.
 891         */
 892        if (ui->del_cmtno != c->cmt_no) {
 893                up_read(&c->commit_sem);
 894                return ubifs_jnl_write_inode(c, inode);
 895        }
 896
 897        err = ubifs_tnc_remove_ino(c, inode->i_ino);
 898        if (err)
 899                ubifs_ro_mode(c, err);
 900        else
 901                ubifs_delete_orphan(c, inode->i_ino);
 902        up_read(&c->commit_sem);
 903        return err;
 904}
 905
 906/**
 907 * ubifs_jnl_rename - rename a directory entry.
 908 * @c: UBIFS file-system description object
 909 * @old_dir: parent inode of directory entry to rename
 910 * @old_dentry: directory entry to rename
 911 * @new_dir: parent inode of directory entry to rename
 912 * @new_dentry: new directory entry (or directory entry to replace)
 913 * @sync: non-zero if the write-buffer has to be synchronized
 914 *
 915 * This function implements the re-name operation which may involve writing up
 916 * to 3 inodes and 2 directory entries. It marks the written inodes as clean
 917 * and returns zero on success. In case of failure, a negative error code is
 918 * returned.
 919 */
 920int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
 921                     const struct dentry *old_dentry,
 922                     const struct inode *new_dir,
 923                     const struct dentry *new_dentry, int sync)
 924{
 925        void *p;
 926        union ubifs_key key;
 927        struct ubifs_dent_node *dent, *dent2;
 928        int err, dlen1, dlen2, ilen, lnum, offs, len;
 929        const struct inode *old_inode = old_dentry->d_inode;
 930        const struct inode *new_inode = new_dentry->d_inode;
 931        int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ;
 932        int last_reference = !!(new_inode && new_inode->i_nlink == 0);
 933        int move = (old_dir != new_dir);
 934        struct ubifs_inode *uninitialized_var(new_ui);
 935
 936        dbg_jnl("dent '%.*s' in dir ino %lu to dent '%.*s' in dir ino %lu",
 937                old_dentry->d_name.len, old_dentry->d_name.name,
 938                old_dir->i_ino, new_dentry->d_name.len,
 939                new_dentry->d_name.name, new_dir->i_ino);
 940        ubifs_assert(ubifs_inode(old_dir)->data_len == 0);
 941        ubifs_assert(ubifs_inode(new_dir)->data_len == 0);
 942        ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex));
 943        ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex));
 944
 945        dlen1 = UBIFS_DENT_NODE_SZ + new_dentry->d_name.len + 1;
 946        dlen2 = UBIFS_DENT_NODE_SZ + old_dentry->d_name.len + 1;
 947        if (new_inode) {
 948                new_ui = ubifs_inode(new_inode);
 949                ubifs_assert(mutex_is_locked(&new_ui->ui_mutex));
 950                ilen = UBIFS_INO_NODE_SZ;
 951                if (!last_reference)
 952                        ilen += new_ui->data_len;
 953        } else
 954                ilen = 0;
 955
 956        aligned_dlen1 = ALIGN(dlen1, 8);
 957        aligned_dlen2 = ALIGN(dlen2, 8);
 958        len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8);
 959        if (old_dir != new_dir)
 960                len += plen;
 961        dent = kmalloc(len, GFP_NOFS);
 962        if (!dent)
 963                return -ENOMEM;
 964
 965        /* Make reservation before allocating sequence numbers */
 966        err = make_reservation(c, BASEHD, len);
 967        if (err)
 968                goto out_free;
 969
 970        /* Make new dent */
 971        dent->ch.node_type = UBIFS_DENT_NODE;
 972        dent_key_init_flash(c, &dent->key, new_dir->i_ino, &new_dentry->d_name);
 973        dent->inum = cpu_to_le64(old_inode->i_ino);
 974        dent->type = get_dent_type(old_inode->i_mode);
 975        dent->nlen = cpu_to_le16(new_dentry->d_name.len);
 976        memcpy(dent->name, new_dentry->d_name.name, new_dentry->d_name.len);
 977        dent->name[new_dentry->d_name.len] = '\0';
 978        zero_dent_node_unused(dent);
 979        ubifs_prep_grp_node(c, dent, dlen1, 0);
 980
 981        /* Make deletion dent */
 982        dent2 = (void *)dent + aligned_dlen1;
 983        dent2->ch.node_type = UBIFS_DENT_NODE;
 984        dent_key_init_flash(c, &dent2->key, old_dir->i_ino,
 985                            &old_dentry->d_name);
 986        dent2->inum = 0;
 987        dent2->type = DT_UNKNOWN;
 988        dent2->nlen = cpu_to_le16(old_dentry->d_name.len);
 989        memcpy(dent2->name, old_dentry->d_name.name, old_dentry->d_name.len);
 990        dent2->name[old_dentry->d_name.len] = '\0';
 991        zero_dent_node_unused(dent2);
 992        ubifs_prep_grp_node(c, dent2, dlen2, 0);
 993
 994        p = (void *)dent2 + aligned_dlen2;
 995        if (new_inode) {
 996                pack_inode(c, p, new_inode, 0);
 997                p += ALIGN(ilen, 8);
 998        }
 999
1000        if (!move)
1001                pack_inode(c, p, old_dir, 1);
1002        else {
1003                pack_inode(c, p, old_dir, 0);
1004                p += ALIGN(plen, 8);
1005                pack_inode(c, p, new_dir, 1);
1006        }
1007
1008        if (last_reference) {
1009                err = ubifs_add_orphan(c, new_inode->i_ino);
1010                if (err) {
1011                        release_head(c, BASEHD);
1012                        goto out_finish;
1013                }
1014                new_ui->del_cmtno = c->cmt_no;
1015        }
1016
1017        err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync);
1018        if (err)
1019                goto out_release;
1020        if (!sync) {
1021                struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1022
1023                ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino);
1024                ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino);
1025                if (new_inode)
1026                        ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf,
1027                                                  new_inode->i_ino);
1028        }
1029        release_head(c, BASEHD);
1030
1031        dent_key_init(c, &key, new_dir->i_ino, &new_dentry->d_name);
1032        err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &new_dentry->d_name);
1033        if (err)
1034                goto out_ro;
1035
1036        err = ubifs_add_dirt(c, lnum, dlen2);
1037        if (err)
1038                goto out_ro;
1039
1040        dent_key_init(c, &key, old_dir->i_ino, &old_dentry->d_name);
1041        err = ubifs_tnc_remove_nm(c, &key, &old_dentry->d_name);
1042        if (err)
1043                goto out_ro;
1044
1045        offs += aligned_dlen1 + aligned_dlen2;
1046        if (new_inode) {
1047                ino_key_init(c, &key, new_inode->i_ino);
1048                err = ubifs_tnc_add(c, &key, lnum, offs, ilen);
1049                if (err)
1050                        goto out_ro;
1051                offs += ALIGN(ilen, 8);
1052        }
1053
1054        ino_key_init(c, &key, old_dir->i_ino);
1055        err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1056        if (err)
1057                goto out_ro;
1058
1059        if (old_dir != new_dir) {
1060                offs += ALIGN(plen, 8);
1061                ino_key_init(c, &key, new_dir->i_ino);
1062                err = ubifs_tnc_add(c, &key, lnum, offs, plen);
1063                if (err)
1064                        goto out_ro;
1065        }
1066
1067        finish_reservation(c);
1068        if (new_inode) {
1069                mark_inode_clean(c, new_ui);
1070                spin_lock(&new_ui->ui_lock);
1071                new_ui->synced_i_size = new_ui->ui_size;
1072                spin_unlock(&new_ui->ui_lock);
1073        }
1074        mark_inode_clean(c, ubifs_inode(old_dir));
1075        if (move)
1076                mark_inode_clean(c, ubifs_inode(new_dir));
1077        kfree(dent);
1078        return 0;
1079
1080out_release:
1081        release_head(c, BASEHD);
1082out_ro:
1083        ubifs_ro_mode(c, err);
1084        if (last_reference)
1085                ubifs_delete_orphan(c, new_inode->i_ino);
1086out_finish:
1087        finish_reservation(c);
1088out_free:
1089        kfree(dent);
1090        return err;
1091}
1092
1093/**
1094 * recomp_data_node - re-compress a truncated data node.
1095 * @dn: data node to re-compress
1096 * @new_len: new length
1097 *
1098 * This function is used when an inode is truncated and the last data node of
1099 * the inode has to be re-compressed and re-written.
1100 */
1101static int recomp_data_node(struct ubifs_data_node *dn, int *new_len)
1102{
1103        void *buf;
1104        int err, len, compr_type, out_len;
1105
1106        out_len = le32_to_cpu(dn->size);
1107        buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
1108        if (!buf)
1109                return -ENOMEM;
1110
1111        len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ;
1112        compr_type = le16_to_cpu(dn->compr_type);
1113        err = ubifs_decompress(&dn->data, len, buf, &out_len, compr_type);
1114        if (err)
1115                goto out;
1116
1117        ubifs_compress(buf, *new_len, &dn->data, &out_len, &compr_type);
1118        ubifs_assert(out_len <= UBIFS_BLOCK_SIZE);
1119        dn->compr_type = cpu_to_le16(compr_type);
1120        dn->size = cpu_to_le32(*new_len);
1121        *new_len = UBIFS_DATA_NODE_SZ + out_len;
1122out:
1123        kfree(buf);
1124        return err;
1125}
1126
1127/**
1128 * ubifs_jnl_truncate - update the journal for a truncation.
1129 * @c: UBIFS file-system description object
1130 * @inode: inode to truncate
1131 * @old_size: old size
1132 * @new_size: new size
1133 *
1134 * When the size of a file decreases due to truncation, a truncation node is
1135 * written, the journal tree is updated, and the last data block is re-written
1136 * if it has been affected. The inode is also updated in order to synchronize
1137 * the new inode size.
1138 *
1139 * This function marks the inode as clean and returns zero on success. In case
1140 * of failure, a negative error code is returned.
1141 */
1142int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode,
1143                       loff_t old_size, loff_t new_size)
1144{
1145        union ubifs_key key, to_key;
1146        struct ubifs_ino_node *ino;
1147        struct ubifs_trun_node *trun;
1148        struct ubifs_data_node *uninitialized_var(dn);
1149        int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode);
1150        struct ubifs_inode *ui = ubifs_inode(inode);
1151        ino_t inum = inode->i_ino;
1152        unsigned int blk;
1153
1154        dbg_jnl("ino %lu, size %lld -> %lld",
1155                (unsigned long)inum, old_size, new_size);
1156        ubifs_assert(!ui->data_len);
1157        ubifs_assert(S_ISREG(inode->i_mode));
1158        ubifs_assert(mutex_is_locked(&ui->ui_mutex));
1159
1160        sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ +
1161             UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR;
1162        ino = kmalloc(sz, GFP_NOFS);
1163        if (!ino)
1164                return -ENOMEM;
1165
1166        trun = (void *)ino + UBIFS_INO_NODE_SZ;
1167        trun->ch.node_type = UBIFS_TRUN_NODE;
1168        trun->inum = cpu_to_le32(inum);
1169        trun->old_size = cpu_to_le64(old_size);
1170        trun->new_size = cpu_to_le64(new_size);
1171        zero_trun_node_unused(trun);
1172
1173        dlen = new_size & (UBIFS_BLOCK_SIZE - 1);
1174        if (dlen) {
1175                /* Get last data block so it can be truncated */
1176                dn = (void *)trun + UBIFS_TRUN_NODE_SZ;
1177                blk = new_size >> UBIFS_BLOCK_SHIFT;
1178                data_key_init(c, &key, inum, blk);
1179                dbg_jnlk(&key, "last block key ");
1180                err = ubifs_tnc_lookup(c, &key, dn);
1181                if (err == -ENOENT)
1182                        dlen = 0; /* Not found (so it is a hole) */
1183                else if (err)
1184                        goto out_free;
1185                else {
1186                        if (le32_to_cpu(dn->size) <= dlen)
1187                                dlen = 0; /* Nothing to do */
1188                        else {
1189                                int compr_type = le16_to_cpu(dn->compr_type);
1190
1191                                if (compr_type != UBIFS_COMPR_NONE) {
1192                                        err = recomp_data_node(dn, &dlen);
1193                                        if (err)
1194                                                goto out_free;
1195                                } else {
1196                                        dn->size = cpu_to_le32(dlen);
1197                                        dlen += UBIFS_DATA_NODE_SZ;
1198                                }
1199                                zero_data_node_unused(dn);
1200                        }
1201                }
1202        }
1203
1204        /* Must make reservation before allocating sequence numbers */
1205        len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ;
1206        if (dlen)
1207                len += dlen;
1208        err = make_reservation(c, BASEHD, len);
1209        if (err)
1210                goto out_free;
1211
1212        pack_inode(c, ino, inode, 0);
1213        ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1);
1214        if (dlen)
1215                ubifs_prep_grp_node(c, dn, dlen, 1);
1216
1217        err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync);
1218        if (err)
1219                goto out_release;
1220        if (!sync)
1221                ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum);
1222        release_head(c, BASEHD);
1223
1224        if (dlen) {
1225                sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ;
1226                err = ubifs_tnc_add(c, &key, lnum, sz, dlen);
1227                if (err)
1228                        goto out_ro;
1229        }
1230
1231        ino_key_init(c, &key, inum);
1232        err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ);
1233        if (err)
1234                goto out_ro;
1235
1236        err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ);
1237        if (err)
1238                goto out_ro;
1239
1240        bit = new_size & (UBIFS_BLOCK_SIZE - 1);
1241        blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0);
1242        data_key_init(c, &key, inum, blk);
1243
1244        bit = old_size & (UBIFS_BLOCK_SIZE - 1);
1245        blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0 : 1);
1246        data_key_init(c, &to_key, inum, blk);
1247
1248        err = ubifs_tnc_remove_range(c, &key, &to_key);
1249        if (err)
1250                goto out_ro;
1251
1252        finish_reservation(c);
1253        spin_lock(&ui->ui_lock);
1254        ui->synced_i_size = ui->ui_size;
1255        spin_unlock(&ui->ui_lock);
1256        mark_inode_clean(c, ui);
1257        kfree(ino);
1258        return 0;
1259
1260out_release:
1261        release_head(c, BASEHD);
1262out_ro:
1263        ubifs_ro_mode(c, err);
1264        finish_reservation(c);
1265out_free:
1266        kfree(ino);
1267        return err;
1268}
1269
1270
1271/**
1272 * ubifs_jnl_delete_xattr - delete an extended attribute.
1273 * @c: UBIFS file-system description object
1274 * @host: host inode
1275 * @inode: extended attribute inode
1276 * @nm: extended attribute entry name
1277 *
1278 * This function delete an extended attribute which is very similar to
1279 * un-linking regular files - it writes a deletion xentry, a deletion inode and
1280 * updates the target inode. Returns zero in case of success and a negative
1281 * error code in case of failure.
1282 */
1283int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host,
1284                           const struct inode *inode, const struct qstr *nm)
1285{
1286        int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen;
1287        struct ubifs_dent_node *xent;
1288        struct ubifs_ino_node *ino;
1289        union ubifs_key xent_key, key1, key2;
1290        int sync = IS_DIRSYNC(host);
1291        struct ubifs_inode *host_ui = ubifs_inode(host);
1292
1293        dbg_jnl("host %lu, xattr ino %lu, name '%s', data len %d",
1294                host->i_ino, inode->i_ino, nm->name,
1295                ubifs_inode(inode)->data_len);
1296        ubifs_assert(inode->i_nlink == 0);
1297        ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1298
1299        /*
1300         * Since we are deleting the inode, we do not bother to attach any data
1301         * to it and assume its length is %UBIFS_INO_NODE_SZ.
1302         */
1303        xlen = UBIFS_DENT_NODE_SZ + nm->len + 1;
1304        aligned_xlen = ALIGN(xlen, 8);
1305        hlen = host_ui->data_len + UBIFS_INO_NODE_SZ;
1306        len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8);
1307
1308        xent = kmalloc(len, GFP_NOFS);
1309        if (!xent)
1310                return -ENOMEM;
1311
1312        /* Make reservation before allocating sequence numbers */
1313        err = make_reservation(c, BASEHD, len);
1314        if (err) {
1315                kfree(xent);
1316                return err;
1317        }
1318
1319        xent->ch.node_type = UBIFS_XENT_NODE;
1320        xent_key_init(c, &xent_key, host->i_ino, nm);
1321        key_write(c, &xent_key, xent->key);
1322        xent->inum = 0;
1323        xent->type = get_dent_type(inode->i_mode);
1324        xent->nlen = cpu_to_le16(nm->len);
1325        memcpy(xent->name, nm->name, nm->len);
1326        xent->name[nm->len] = '\0';
1327        zero_dent_node_unused(xent);
1328        ubifs_prep_grp_node(c, xent, xlen, 0);
1329
1330        ino = (void *)xent + aligned_xlen;
1331        pack_inode(c, ino, inode, 0);
1332        ino = (void *)ino + UBIFS_INO_NODE_SZ;
1333        pack_inode(c, ino, host, 1);
1334
1335        err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync);
1336        if (!sync && !err)
1337                ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino);
1338        release_head(c, BASEHD);
1339        kfree(xent);
1340        if (err)
1341                goto out_ro;
1342
1343        /* Remove the extended attribute entry from TNC */
1344        err = ubifs_tnc_remove_nm(c, &xent_key, nm);
1345        if (err)
1346                goto out_ro;
1347        err = ubifs_add_dirt(c, lnum, xlen);
1348        if (err)
1349                goto out_ro;
1350
1351        /*
1352         * Remove all nodes belonging to the extended attribute inode from TNC.
1353         * Well, there actually must be only one node - the inode itself.
1354         */
1355        lowest_ino_key(c, &key1, inode->i_ino);
1356        highest_ino_key(c, &key2, inode->i_ino);
1357        err = ubifs_tnc_remove_range(c, &key1, &key2);
1358        if (err)
1359                goto out_ro;
1360        err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ);
1361        if (err)
1362                goto out_ro;
1363
1364        /* And update TNC with the new host inode position */
1365        ino_key_init(c, &key1, host->i_ino);
1366        err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen);
1367        if (err)
1368                goto out_ro;
1369
1370        finish_reservation(c);
1371        spin_lock(&host_ui->ui_lock);
1372        host_ui->synced_i_size = host_ui->ui_size;
1373        spin_unlock(&host_ui->ui_lock);
1374        mark_inode_clean(c, host_ui);
1375        return 0;
1376
1377out_ro:
1378        ubifs_ro_mode(c, err);
1379        finish_reservation(c);
1380        return err;
1381}
1382
1383/**
1384 * ubifs_jnl_change_xattr - change an extended attribute.
1385 * @c: UBIFS file-system description object
1386 * @inode: extended attribute inode
1387 * @host: host inode
1388 *
1389 * This function writes the updated version of an extended attribute inode and
1390 * the host inode to the journal (to the base head). The host inode is written
1391 * after the extended attribute inode in order to guarantee that the extended
1392 * attribute will be flushed when the inode is synchronized by 'fsync()' and
1393 * consequently, the write-buffer is synchronized. This function returns zero
1394 * in case of success and a negative error code in case of failure.
1395 */
1396int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode,
1397                           const struct inode *host)
1398{
1399        int err, len1, len2, aligned_len, aligned_len1, lnum, offs;
1400        struct ubifs_inode *host_ui = ubifs_inode(host);
1401        struct ubifs_ino_node *ino;
1402        union ubifs_key key;
1403        int sync = IS_DIRSYNC(host);
1404
1405        dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino);
1406        ubifs_assert(host->i_nlink > 0);
1407        ubifs_assert(inode->i_nlink > 0);
1408        ubifs_assert(mutex_is_locked(&host_ui->ui_mutex));
1409
1410        len1 = UBIFS_INO_NODE_SZ + host_ui->data_len;
1411        len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len;
1412        aligned_len1 = ALIGN(len1, 8);
1413        aligned_len = aligned_len1 + ALIGN(len2, 8);
1414
1415        ino = kmalloc(aligned_len, GFP_NOFS);
1416        if (!ino)
1417                return -ENOMEM;
1418
1419        /* Make reservation before allocating sequence numbers */
1420        err = make_reservation(c, BASEHD, aligned_len);
1421        if (err)
1422                goto out_free;
1423
1424        pack_inode(c, ino, host, 0);
1425        pack_inode(c, (void *)ino + aligned_len1, inode, 1);
1426
1427        err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0);
1428        if (!sync && !err) {
1429                struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf;
1430
1431                ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino);
1432                ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino);
1433        }
1434        release_head(c, BASEHD);
1435        if (err)
1436                goto out_ro;
1437
1438        ino_key_init(c, &key, host->i_ino);
1439        err = ubifs_tnc_add(c, &key, lnum, offs, len1);
1440        if (err)
1441                goto out_ro;
1442
1443        ino_key_init(c, &key, inode->i_ino);
1444        err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2);
1445        if (err)
1446                goto out_ro;
1447
1448        finish_reservation(c);
1449        spin_lock(&host_ui->ui_lock);
1450        host_ui->synced_i_size = host_ui->ui_size;
1451        spin_unlock(&host_ui->ui_lock);
1452        mark_inode_clean(c, host_ui);
1453        kfree(ino);
1454        return 0;
1455
1456out_ro:
1457        ubifs_ro_mode(c, err);
1458        finish_reservation(c);
1459out_free:
1460        kfree(ino);
1461        return err;
1462}
1463
1464
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.