uboot/fs/ubifs/lpt_commit.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * This file is part of UBIFS.
   4 *
   5 * Copyright (C) 2006-2008 Nokia Corporation.
   6 *
   7 * Authors: Adrian Hunter
   8 *          Artem Bityutskiy (Битюцкий Артём)
   9 */
  10
  11/*
  12 * This file implements commit-related functionality of the LEB properties
  13 * subsystem.
  14 */
  15
  16#ifndef __UBOOT__
  17#include <log.h>
  18#include <dm/devres.h>
  19#include <linux/crc16.h>
  20#include <linux/slab.h>
  21#include <linux/random.h>
  22#else
  23#include <linux/bitops.h>
  24#include <linux/compat.h>
  25#include <linux/err.h>
  26#include "crc16.h"
  27#endif
  28#include "ubifs.h"
  29
  30#ifndef __UBOOT__
  31static int dbg_populate_lsave(struct ubifs_info *c);
  32#endif
  33
  34/**
  35 * first_dirty_cnode - find first dirty cnode.
  36 * @c: UBIFS file-system description object
  37 * @nnode: nnode at which to start
  38 *
  39 * This function returns the first dirty cnode or %NULL if there is not one.
  40 */
  41static struct ubifs_cnode *first_dirty_cnode(struct ubifs_nnode *nnode)
  42{
  43        ubifs_assert(nnode);
  44        while (1) {
  45                int i, cont = 0;
  46
  47                for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
  48                        struct ubifs_cnode *cnode;
  49
  50                        cnode = nnode->nbranch[i].cnode;
  51                        if (cnode &&
  52                            test_bit(DIRTY_CNODE, &cnode->flags)) {
  53                                if (cnode->level == 0)
  54                                        return cnode;
  55                                nnode = (struct ubifs_nnode *)cnode;
  56                                cont = 1;
  57                                break;
  58                        }
  59                }
  60                if (!cont)
  61                        return (struct ubifs_cnode *)nnode;
  62        }
  63}
  64
  65/**
  66 * next_dirty_cnode - find next dirty cnode.
  67 * @cnode: cnode from which to begin searching
  68 *
  69 * This function returns the next dirty cnode or %NULL if there is not one.
  70 */
  71static struct ubifs_cnode *next_dirty_cnode(struct ubifs_cnode *cnode)
  72{
  73        struct ubifs_nnode *nnode;
  74        int i;
  75
  76        ubifs_assert(cnode);
  77        nnode = cnode->parent;
  78        if (!nnode)
  79                return NULL;
  80        for (i = cnode->iip + 1; i < UBIFS_LPT_FANOUT; i++) {
  81                cnode = nnode->nbranch[i].cnode;
  82                if (cnode && test_bit(DIRTY_CNODE, &cnode->flags)) {
  83                        if (cnode->level == 0)
  84                                return cnode; /* cnode is a pnode */
  85                        /* cnode is a nnode */
  86                        return first_dirty_cnode((struct ubifs_nnode *)cnode);
  87                }
  88        }
  89        return (struct ubifs_cnode *)nnode;
  90}
  91
  92/**
  93 * get_cnodes_to_commit - create list of dirty cnodes to commit.
  94 * @c: UBIFS file-system description object
  95 *
  96 * This function returns the number of cnodes to commit.
  97 */
  98static int get_cnodes_to_commit(struct ubifs_info *c)
  99{
 100        struct ubifs_cnode *cnode, *cnext;
 101        int cnt = 0;
 102
 103        if (!c->nroot)
 104                return 0;
 105
 106        if (!test_bit(DIRTY_CNODE, &c->nroot->flags))
 107                return 0;
 108
 109        c->lpt_cnext = first_dirty_cnode(c->nroot);
 110        cnode = c->lpt_cnext;
 111        if (!cnode)
 112                return 0;
 113        cnt += 1;
 114        while (1) {
 115                ubifs_assert(!test_bit(COW_CNODE, &cnode->flags));
 116                __set_bit(COW_CNODE, &cnode->flags);
 117                cnext = next_dirty_cnode(cnode);
 118                if (!cnext) {
 119                        cnode->cnext = c->lpt_cnext;
 120                        break;
 121                }
 122                cnode->cnext = cnext;
 123                cnode = cnext;
 124                cnt += 1;
 125        }
 126        dbg_cmt("committing %d cnodes", cnt);
 127        dbg_lp("committing %d cnodes", cnt);
 128        ubifs_assert(cnt == c->dirty_nn_cnt + c->dirty_pn_cnt);
 129        return cnt;
 130}
 131
 132/**
 133 * upd_ltab - update LPT LEB properties.
 134 * @c: UBIFS file-system description object
 135 * @lnum: LEB number
 136 * @free: amount of free space
 137 * @dirty: amount of dirty space to add
 138 */
 139static void upd_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
 140{
 141        dbg_lp("LEB %d free %d dirty %d to %d +%d",
 142               lnum, c->ltab[lnum - c->lpt_first].free,
 143               c->ltab[lnum - c->lpt_first].dirty, free, dirty);
 144        ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
 145        c->ltab[lnum - c->lpt_first].free = free;
 146        c->ltab[lnum - c->lpt_first].dirty += dirty;
 147}
 148
 149/**
 150 * alloc_lpt_leb - allocate an LPT LEB that is empty.
 151 * @c: UBIFS file-system description object
 152 * @lnum: LEB number is passed and returned here
 153 *
 154 * This function finds the next empty LEB in the ltab starting from @lnum. If a
 155 * an empty LEB is found it is returned in @lnum and the function returns %0.
 156 * Otherwise the function returns -ENOSPC.  Note however, that LPT is designed
 157 * never to run out of space.
 158 */
 159static int alloc_lpt_leb(struct ubifs_info *c, int *lnum)
 160{
 161        int i, n;
 162
 163        n = *lnum - c->lpt_first + 1;
 164        for (i = n; i < c->lpt_lebs; i++) {
 165                if (c->ltab[i].tgc || c->ltab[i].cmt)
 166                        continue;
 167                if (c->ltab[i].free == c->leb_size) {
 168                        c->ltab[i].cmt = 1;
 169                        *lnum = i + c->lpt_first;
 170                        return 0;
 171                }
 172        }
 173
 174        for (i = 0; i < n; i++) {
 175                if (c->ltab[i].tgc || c->ltab[i].cmt)
 176                        continue;
 177                if (c->ltab[i].free == c->leb_size) {
 178                        c->ltab[i].cmt = 1;
 179                        *lnum = i + c->lpt_first;
 180                        return 0;
 181                }
 182        }
 183        return -ENOSPC;
 184}
 185
 186/**
 187 * layout_cnodes - layout cnodes for commit.
 188 * @c: UBIFS file-system description object
 189 *
 190 * This function returns %0 on success and a negative error code on failure.
 191 */
 192static int layout_cnodes(struct ubifs_info *c)
 193{
 194        int lnum, offs, len, alen, done_lsave, done_ltab, err;
 195        struct ubifs_cnode *cnode;
 196
 197        err = dbg_chk_lpt_sz(c, 0, 0);
 198        if (err)
 199                return err;
 200        cnode = c->lpt_cnext;
 201        if (!cnode)
 202                return 0;
 203        lnum = c->nhead_lnum;
 204        offs = c->nhead_offs;
 205        /* Try to place lsave and ltab nicely */
 206        done_lsave = !c->big_lpt;
 207        done_ltab = 0;
 208        if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
 209                done_lsave = 1;
 210                c->lsave_lnum = lnum;
 211                c->lsave_offs = offs;
 212                offs += c->lsave_sz;
 213                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
 214        }
 215
 216        if (offs + c->ltab_sz <= c->leb_size) {
 217                done_ltab = 1;
 218                c->ltab_lnum = lnum;
 219                c->ltab_offs = offs;
 220                offs += c->ltab_sz;
 221                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
 222        }
 223
 224        do {
 225                if (cnode->level) {
 226                        len = c->nnode_sz;
 227                        c->dirty_nn_cnt -= 1;
 228                } else {
 229                        len = c->pnode_sz;
 230                        c->dirty_pn_cnt -= 1;
 231                }
 232                while (offs + len > c->leb_size) {
 233                        alen = ALIGN(offs, c->min_io_size);
 234                        upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
 235                        dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
 236                        err = alloc_lpt_leb(c, &lnum);
 237                        if (err)
 238                                goto no_space;
 239                        offs = 0;
 240                        ubifs_assert(lnum >= c->lpt_first &&
 241                                     lnum <= c->lpt_last);
 242                        /* Try to place lsave and ltab nicely */
 243                        if (!done_lsave) {
 244                                done_lsave = 1;
 245                                c->lsave_lnum = lnum;
 246                                c->lsave_offs = offs;
 247                                offs += c->lsave_sz;
 248                                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
 249                                continue;
 250                        }
 251                        if (!done_ltab) {
 252                                done_ltab = 1;
 253                                c->ltab_lnum = lnum;
 254                                c->ltab_offs = offs;
 255                                offs += c->ltab_sz;
 256                                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
 257                                continue;
 258                        }
 259                        break;
 260                }
 261                if (cnode->parent) {
 262                        cnode->parent->nbranch[cnode->iip].lnum = lnum;
 263                        cnode->parent->nbranch[cnode->iip].offs = offs;
 264                } else {
 265                        c->lpt_lnum = lnum;
 266                        c->lpt_offs = offs;
 267                }
 268                offs += len;
 269                dbg_chk_lpt_sz(c, 1, len);
 270                cnode = cnode->cnext;
 271        } while (cnode && cnode != c->lpt_cnext);
 272
 273        /* Make sure to place LPT's save table */
 274        if (!done_lsave) {
 275                if (offs + c->lsave_sz > c->leb_size) {
 276                        alen = ALIGN(offs, c->min_io_size);
 277                        upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
 278                        dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
 279                        err = alloc_lpt_leb(c, &lnum);
 280                        if (err)
 281                                goto no_space;
 282                        offs = 0;
 283                        ubifs_assert(lnum >= c->lpt_first &&
 284                                     lnum <= c->lpt_last);
 285                }
 286                done_lsave = 1;
 287                c->lsave_lnum = lnum;
 288                c->lsave_offs = offs;
 289                offs += c->lsave_sz;
 290                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
 291        }
 292
 293        /* Make sure to place LPT's own lprops table */
 294        if (!done_ltab) {
 295                if (offs + c->ltab_sz > c->leb_size) {
 296                        alen = ALIGN(offs, c->min_io_size);
 297                        upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
 298                        dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
 299                        err = alloc_lpt_leb(c, &lnum);
 300                        if (err)
 301                                goto no_space;
 302                        offs = 0;
 303                        ubifs_assert(lnum >= c->lpt_first &&
 304                                     lnum <= c->lpt_last);
 305                }
 306                c->ltab_lnum = lnum;
 307                c->ltab_offs = offs;
 308                offs += c->ltab_sz;
 309                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
 310        }
 311
 312        alen = ALIGN(offs, c->min_io_size);
 313        upd_ltab(c, lnum, c->leb_size - alen, alen - offs);
 314        dbg_chk_lpt_sz(c, 4, alen - offs);
 315        err = dbg_chk_lpt_sz(c, 3, alen);
 316        if (err)
 317                return err;
 318        return 0;
 319
 320no_space:
 321        ubifs_err(c, "LPT out of space at LEB %d:%d needing %d, done_ltab %d, done_lsave %d",
 322                  lnum, offs, len, done_ltab, done_lsave);
 323        ubifs_dump_lpt_info(c);
 324        ubifs_dump_lpt_lebs(c);
 325        dump_stack();
 326        return err;
 327}
 328
 329#ifndef __UBOOT__
 330/**
 331 * realloc_lpt_leb - allocate an LPT LEB that is empty.
 332 * @c: UBIFS file-system description object
 333 * @lnum: LEB number is passed and returned here
 334 *
 335 * This function duplicates exactly the results of the function alloc_lpt_leb.
 336 * It is used during end commit to reallocate the same LEB numbers that were
 337 * allocated by alloc_lpt_leb during start commit.
 338 *
 339 * This function finds the next LEB that was allocated by the alloc_lpt_leb
 340 * function starting from @lnum. If a LEB is found it is returned in @lnum and
 341 * the function returns %0. Otherwise the function returns -ENOSPC.
 342 * Note however, that LPT is designed never to run out of space.
 343 */
 344static int realloc_lpt_leb(struct ubifs_info *c, int *lnum)
 345{
 346        int i, n;
 347
 348        n = *lnum - c->lpt_first + 1;
 349        for (i = n; i < c->lpt_lebs; i++)
 350                if (c->ltab[i].cmt) {
 351                        c->ltab[i].cmt = 0;
 352                        *lnum = i + c->lpt_first;
 353                        return 0;
 354                }
 355
 356        for (i = 0; i < n; i++)
 357                if (c->ltab[i].cmt) {
 358                        c->ltab[i].cmt = 0;
 359                        *lnum = i + c->lpt_first;
 360                        return 0;
 361                }
 362        return -ENOSPC;
 363}
 364
 365/**
 366 * write_cnodes - write cnodes for commit.
 367 * @c: UBIFS file-system description object
 368 *
 369 * This function returns %0 on success and a negative error code on failure.
 370 */
 371static int write_cnodes(struct ubifs_info *c)
 372{
 373        int lnum, offs, len, from, err, wlen, alen, done_ltab, done_lsave;
 374        struct ubifs_cnode *cnode;
 375        void *buf = c->lpt_buf;
 376
 377        cnode = c->lpt_cnext;
 378        if (!cnode)
 379                return 0;
 380        lnum = c->nhead_lnum;
 381        offs = c->nhead_offs;
 382        from = offs;
 383        /* Ensure empty LEB is unmapped */
 384        if (offs == 0) {
 385                err = ubifs_leb_unmap(c, lnum);
 386                if (err)
 387                        return err;
 388        }
 389        /* Try to place lsave and ltab nicely */
 390        done_lsave = !c->big_lpt;
 391        done_ltab = 0;
 392        if (!done_lsave && offs + c->lsave_sz <= c->leb_size) {
 393                done_lsave = 1;
 394                ubifs_pack_lsave(c, buf + offs, c->lsave);
 395                offs += c->lsave_sz;
 396                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
 397        }
 398
 399        if (offs + c->ltab_sz <= c->leb_size) {
 400                done_ltab = 1;
 401                ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
 402                offs += c->ltab_sz;
 403                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
 404        }
 405
 406        /* Loop for each cnode */
 407        do {
 408                if (cnode->level)
 409                        len = c->nnode_sz;
 410                else
 411                        len = c->pnode_sz;
 412                while (offs + len > c->leb_size) {
 413                        wlen = offs - from;
 414                        if (wlen) {
 415                                alen = ALIGN(wlen, c->min_io_size);
 416                                memset(buf + offs, 0xff, alen - wlen);
 417                                err = ubifs_leb_write(c, lnum, buf + from, from,
 418                                                       alen);
 419                                if (err)
 420                                        return err;
 421                        }
 422                        dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
 423                        err = realloc_lpt_leb(c, &lnum);
 424                        if (err)
 425                                goto no_space;
 426                        offs = from = 0;
 427                        ubifs_assert(lnum >= c->lpt_first &&
 428                                     lnum <= c->lpt_last);
 429                        err = ubifs_leb_unmap(c, lnum);
 430                        if (err)
 431                                return err;
 432                        /* Try to place lsave and ltab nicely */
 433                        if (!done_lsave) {
 434                                done_lsave = 1;
 435                                ubifs_pack_lsave(c, buf + offs, c->lsave);
 436                                offs += c->lsave_sz;
 437                                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
 438                                continue;
 439                        }
 440                        if (!done_ltab) {
 441                                done_ltab = 1;
 442                                ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
 443                                offs += c->ltab_sz;
 444                                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
 445                                continue;
 446                        }
 447                        break;
 448                }
 449                if (cnode->level)
 450                        ubifs_pack_nnode(c, buf + offs,
 451                                         (struct ubifs_nnode *)cnode);
 452                else
 453                        ubifs_pack_pnode(c, buf + offs,
 454                                         (struct ubifs_pnode *)cnode);
 455                /*
 456                 * The reason for the barriers is the same as in case of TNC.
 457                 * See comment in 'write_index()'. 'dirty_cow_nnode()' and
 458                 * 'dirty_cow_pnode()' are the functions for which this is
 459                 * important.
 460                 */
 461                clear_bit(DIRTY_CNODE, &cnode->flags);
 462                smp_mb__before_atomic();
 463                clear_bit(COW_CNODE, &cnode->flags);
 464                smp_mb__after_atomic();
 465                offs += len;
 466                dbg_chk_lpt_sz(c, 1, len);
 467                cnode = cnode->cnext;
 468        } while (cnode && cnode != c->lpt_cnext);
 469
 470        /* Make sure to place LPT's save table */
 471        if (!done_lsave) {
 472                if (offs + c->lsave_sz > c->leb_size) {
 473                        wlen = offs - from;
 474                        alen = ALIGN(wlen, c->min_io_size);
 475                        memset(buf + offs, 0xff, alen - wlen);
 476                        err = ubifs_leb_write(c, lnum, buf + from, from, alen);
 477                        if (err)
 478                                return err;
 479                        dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
 480                        err = realloc_lpt_leb(c, &lnum);
 481                        if (err)
 482                                goto no_space;
 483                        offs = from = 0;
 484                        ubifs_assert(lnum >= c->lpt_first &&
 485                                     lnum <= c->lpt_last);
 486                        err = ubifs_leb_unmap(c, lnum);
 487                        if (err)
 488                                return err;
 489                }
 490                done_lsave = 1;
 491                ubifs_pack_lsave(c, buf + offs, c->lsave);
 492                offs += c->lsave_sz;
 493                dbg_chk_lpt_sz(c, 1, c->lsave_sz);
 494        }
 495
 496        /* Make sure to place LPT's own lprops table */
 497        if (!done_ltab) {
 498                if (offs + c->ltab_sz > c->leb_size) {
 499                        wlen = offs - from;
 500                        alen = ALIGN(wlen, c->min_io_size);
 501                        memset(buf + offs, 0xff, alen - wlen);
 502                        err = ubifs_leb_write(c, lnum, buf + from, from, alen);
 503                        if (err)
 504                                return err;
 505                        dbg_chk_lpt_sz(c, 2, c->leb_size - offs);
 506                        err = realloc_lpt_leb(c, &lnum);
 507                        if (err)
 508                                goto no_space;
 509                        offs = from = 0;
 510                        ubifs_assert(lnum >= c->lpt_first &&
 511                                     lnum <= c->lpt_last);
 512                        err = ubifs_leb_unmap(c, lnum);
 513                        if (err)
 514                                return err;
 515                }
 516                ubifs_pack_ltab(c, buf + offs, c->ltab_cmt);
 517                offs += c->ltab_sz;
 518                dbg_chk_lpt_sz(c, 1, c->ltab_sz);
 519        }
 520
 521        /* Write remaining data in buffer */
 522        wlen = offs - from;
 523        alen = ALIGN(wlen, c->min_io_size);
 524        memset(buf + offs, 0xff, alen - wlen);
 525        err = ubifs_leb_write(c, lnum, buf + from, from, alen);
 526        if (err)
 527                return err;
 528
 529        dbg_chk_lpt_sz(c, 4, alen - wlen);
 530        err = dbg_chk_lpt_sz(c, 3, ALIGN(offs, c->min_io_size));
 531        if (err)
 532                return err;
 533
 534        c->nhead_lnum = lnum;
 535        c->nhead_offs = ALIGN(offs, c->min_io_size);
 536
 537        dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
 538        dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
 539        dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
 540        if (c->big_lpt)
 541                dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
 542
 543        return 0;
 544
 545no_space:
 546        ubifs_err(c, "LPT out of space mismatch at LEB %d:%d needing %d, done_ltab %d, done_lsave %d",
 547                  lnum, offs, len, done_ltab, done_lsave);
 548        ubifs_dump_lpt_info(c);
 549        ubifs_dump_lpt_lebs(c);
 550        dump_stack();
 551        return err;
 552}
 553#endif
 554
 555/**
 556 * next_pnode_to_dirty - find next pnode to dirty.
 557 * @c: UBIFS file-system description object
 558 * @pnode: pnode
 559 *
 560 * This function returns the next pnode to dirty or %NULL if there are no more
 561 * pnodes.  Note that pnodes that have never been written (lnum == 0) are
 562 * skipped.
 563 */
 564static struct ubifs_pnode *next_pnode_to_dirty(struct ubifs_info *c,
 565                                               struct ubifs_pnode *pnode)
 566{
 567        struct ubifs_nnode *nnode;
 568        int iip;
 569
 570        /* Try to go right */
 571        nnode = pnode->parent;
 572        for (iip = pnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
 573                if (nnode->nbranch[iip].lnum)
 574                        return ubifs_get_pnode(c, nnode, iip);
 575        }
 576
 577        /* Go up while can't go right */
 578        do {
 579                iip = nnode->iip + 1;
 580                nnode = nnode->parent;
 581                if (!nnode)
 582                        return NULL;
 583                for (; iip < UBIFS_LPT_FANOUT; iip++) {
 584                        if (nnode->nbranch[iip].lnum)
 585                                break;
 586                }
 587        } while (iip >= UBIFS_LPT_FANOUT);
 588
 589        /* Go right */
 590        nnode = ubifs_get_nnode(c, nnode, iip);
 591        if (IS_ERR(nnode))
 592                return (void *)nnode;
 593
 594        /* Go down to level 1 */
 595        while (nnode->level > 1) {
 596                for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++) {
 597                        if (nnode->nbranch[iip].lnum)
 598                                break;
 599                }
 600                if (iip >= UBIFS_LPT_FANOUT) {
 601                        /*
 602                         * Should not happen, but we need to keep going
 603                         * if it does.
 604                         */
 605                        iip = 0;
 606                }
 607                nnode = ubifs_get_nnode(c, nnode, iip);
 608                if (IS_ERR(nnode))
 609                        return (void *)nnode;
 610        }
 611
 612        for (iip = 0; iip < UBIFS_LPT_FANOUT; iip++)
 613                if (nnode->nbranch[iip].lnum)
 614                        break;
 615        if (iip >= UBIFS_LPT_FANOUT)
 616                /* Should not happen, but we need to keep going if it does */
 617                iip = 0;
 618        return ubifs_get_pnode(c, nnode, iip);
 619}
 620
 621/**
 622 * pnode_lookup - lookup a pnode in the LPT.
 623 * @c: UBIFS file-system description object
 624 * @i: pnode number (0 to main_lebs - 1)
 625 *
 626 * This function returns a pointer to the pnode on success or a negative
 627 * error code on failure.
 628 */
 629static struct ubifs_pnode *pnode_lookup(struct ubifs_info *c, int i)
 630{
 631        int err, h, iip, shft;
 632        struct ubifs_nnode *nnode;
 633
 634        if (!c->nroot) {
 635                err = ubifs_read_nnode(c, NULL, 0);
 636                if (err)
 637                        return ERR_PTR(err);
 638        }
 639        i <<= UBIFS_LPT_FANOUT_SHIFT;
 640        nnode = c->nroot;
 641        shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
 642        for (h = 1; h < c->lpt_hght; h++) {
 643                iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
 644                shft -= UBIFS_LPT_FANOUT_SHIFT;
 645                nnode = ubifs_get_nnode(c, nnode, iip);
 646                if (IS_ERR(nnode))
 647                        return ERR_CAST(nnode);
 648        }
 649        iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
 650        return ubifs_get_pnode(c, nnode, iip);
 651}
 652
 653/**
 654 * add_pnode_dirt - add dirty space to LPT LEB properties.
 655 * @c: UBIFS file-system description object
 656 * @pnode: pnode for which to add dirt
 657 */
 658static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
 659{
 660        ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
 661                           c->pnode_sz);
 662}
 663
 664/**
 665 * do_make_pnode_dirty - mark a pnode dirty.
 666 * @c: UBIFS file-system description object
 667 * @pnode: pnode to mark dirty
 668 */
 669static void do_make_pnode_dirty(struct ubifs_info *c, struct ubifs_pnode *pnode)
 670{
 671        /* Assumes cnext list is empty i.e. not called during commit */
 672        if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
 673                struct ubifs_nnode *nnode;
 674
 675                c->dirty_pn_cnt += 1;
 676                add_pnode_dirt(c, pnode);
 677                /* Mark parent and ancestors dirty too */
 678                nnode = pnode->parent;
 679                while (nnode) {
 680                        if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
 681                                c->dirty_nn_cnt += 1;
 682                                ubifs_add_nnode_dirt(c, nnode);
 683                                nnode = nnode->parent;
 684                        } else
 685                                break;
 686                }
 687        }
 688}
 689
 690/**
 691 * make_tree_dirty - mark the entire LEB properties tree dirty.
 692 * @c: UBIFS file-system description object
 693 *
 694 * This function is used by the "small" LPT model to cause the entire LEB
 695 * properties tree to be written.  The "small" LPT model does not use LPT
 696 * garbage collection because it is more efficient to write the entire tree
 697 * (because it is small).
 698 *
 699 * This function returns %0 on success and a negative error code on failure.
 700 */
 701static int make_tree_dirty(struct ubifs_info *c)
 702{
 703        struct ubifs_pnode *pnode;
 704
 705        pnode = pnode_lookup(c, 0);
 706        if (IS_ERR(pnode))
 707                return PTR_ERR(pnode);
 708
 709        while (pnode) {
 710                do_make_pnode_dirty(c, pnode);
 711                pnode = next_pnode_to_dirty(c, pnode);
 712                if (IS_ERR(pnode))
 713                        return PTR_ERR(pnode);
 714        }
 715        return 0;
 716}
 717
 718/**
 719 * need_write_all - determine if the LPT area is running out of free space.
 720 * @c: UBIFS file-system description object
 721 *
 722 * This function returns %1 if the LPT area is running out of free space and %0
 723 * if it is not.
 724 */
 725static int need_write_all(struct ubifs_info *c)
 726{
 727        long long free = 0;
 728        int i;
 729
 730        for (i = 0; i < c->lpt_lebs; i++) {
 731                if (i + c->lpt_first == c->nhead_lnum)
 732                        free += c->leb_size - c->nhead_offs;
 733                else if (c->ltab[i].free == c->leb_size)
 734                        free += c->leb_size;
 735                else if (c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
 736                        free += c->leb_size;
 737        }
 738        /* Less than twice the size left */
 739        if (free <= c->lpt_sz * 2)
 740                return 1;
 741        return 0;
 742}
 743
 744/**
 745 * lpt_tgc_start - start trivial garbage collection of LPT LEBs.
 746 * @c: UBIFS file-system description object
 747 *
 748 * LPT trivial garbage collection is where a LPT LEB contains only dirty and
 749 * free space and so may be reused as soon as the next commit is completed.
 750 * This function is called during start commit to mark LPT LEBs for trivial GC.
 751 */
 752static void lpt_tgc_start(struct ubifs_info *c)
 753{
 754        int i;
 755
 756        for (i = 0; i < c->lpt_lebs; i++) {
 757                if (i + c->lpt_first == c->nhead_lnum)
 758                        continue;
 759                if (c->ltab[i].dirty > 0 &&
 760                    c->ltab[i].free + c->ltab[i].dirty == c->leb_size) {
 761                        c->ltab[i].tgc = 1;
 762                        c->ltab[i].free = c->leb_size;
 763                        c->ltab[i].dirty = 0;
 764                        dbg_lp("LEB %d", i + c->lpt_first);
 765                }
 766        }
 767}
 768
 769/**
 770 * lpt_tgc_end - end trivial garbage collection of LPT LEBs.
 771 * @c: UBIFS file-system description object
 772 *
 773 * LPT trivial garbage collection is where a LPT LEB contains only dirty and
 774 * free space and so may be reused as soon as the next commit is completed.
 775 * This function is called after the commit is completed (master node has been
 776 * written) and un-maps LPT LEBs that were marked for trivial GC.
 777 */
 778static int lpt_tgc_end(struct ubifs_info *c)
 779{
 780        int i, err;
 781
 782        for (i = 0; i < c->lpt_lebs; i++)
 783                if (c->ltab[i].tgc) {
 784                        err = ubifs_leb_unmap(c, i + c->lpt_first);
 785                        if (err)
 786                                return err;
 787                        c->ltab[i].tgc = 0;
 788                        dbg_lp("LEB %d", i + c->lpt_first);
 789                }
 790        return 0;
 791}
 792
 793/**
 794 * populate_lsave - fill the lsave array with important LEB numbers.
 795 * @c: the UBIFS file-system description object
 796 *
 797 * This function is only called for the "big" model. It records a small number
 798 * of LEB numbers of important LEBs.  Important LEBs are ones that are (from
 799 * most important to least important): empty, freeable, freeable index, dirty
 800 * index, dirty or free. Upon mount, we read this list of LEB numbers and bring
 801 * their pnodes into memory.  That will stop us from having to scan the LPT
 802 * straight away. For the "small" model we assume that scanning the LPT is no
 803 * big deal.
 804 */
 805static void populate_lsave(struct ubifs_info *c)
 806{
 807        struct ubifs_lprops *lprops;
 808        struct ubifs_lpt_heap *heap;
 809        int i, cnt = 0;
 810
 811        ubifs_assert(c->big_lpt);
 812        if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
 813                c->lpt_drty_flgs |= LSAVE_DIRTY;
 814                ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
 815        }
 816
 817#ifndef __UBOOT__
 818        if (dbg_populate_lsave(c))
 819                return;
 820#endif
 821
 822        list_for_each_entry(lprops, &c->empty_list, list) {
 823                c->lsave[cnt++] = lprops->lnum;
 824                if (cnt >= c->lsave_cnt)
 825                        return;
 826        }
 827        list_for_each_entry(lprops, &c->freeable_list, list) {
 828                c->lsave[cnt++] = lprops->lnum;
 829                if (cnt >= c->lsave_cnt)
 830                        return;
 831        }
 832        list_for_each_entry(lprops, &c->frdi_idx_list, list) {
 833                c->lsave[cnt++] = lprops->lnum;
 834                if (cnt >= c->lsave_cnt)
 835                        return;
 836        }
 837        heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
 838        for (i = 0; i < heap->cnt; i++) {
 839                c->lsave[cnt++] = heap->arr[i]->lnum;
 840                if (cnt >= c->lsave_cnt)
 841                        return;
 842        }
 843        heap = &c->lpt_heap[LPROPS_DIRTY - 1];
 844        for (i = 0; i < heap->cnt; i++) {
 845                c->lsave[cnt++] = heap->arr[i]->lnum;
 846                if (cnt >= c->lsave_cnt)
 847                        return;
 848        }
 849        heap = &c->lpt_heap[LPROPS_FREE - 1];
 850        for (i = 0; i < heap->cnt; i++) {
 851                c->lsave[cnt++] = heap->arr[i]->lnum;
 852                if (cnt >= c->lsave_cnt)
 853                        return;
 854        }
 855        /* Fill it up completely */
 856        while (cnt < c->lsave_cnt)
 857                c->lsave[cnt++] = c->main_first;
 858}
 859
 860/**
 861 * nnode_lookup - lookup a nnode in the LPT.
 862 * @c: UBIFS file-system description object
 863 * @i: nnode number
 864 *
 865 * This function returns a pointer to the nnode on success or a negative
 866 * error code on failure.
 867 */
 868static struct ubifs_nnode *nnode_lookup(struct ubifs_info *c, int i)
 869{
 870        int err, iip;
 871        struct ubifs_nnode *nnode;
 872
 873        if (!c->nroot) {
 874                err = ubifs_read_nnode(c, NULL, 0);
 875                if (err)
 876                        return ERR_PTR(err);
 877        }
 878        nnode = c->nroot;
 879        while (1) {
 880                iip = i & (UBIFS_LPT_FANOUT - 1);
 881                i >>= UBIFS_LPT_FANOUT_SHIFT;
 882                if (!i)
 883                        break;
 884                nnode = ubifs_get_nnode(c, nnode, iip);
 885                if (IS_ERR(nnode))
 886                        return nnode;
 887        }
 888        return nnode;
 889}
 890
 891/**
 892 * make_nnode_dirty - find a nnode and, if found, make it dirty.
 893 * @c: UBIFS file-system description object
 894 * @node_num: nnode number of nnode to make dirty
 895 * @lnum: LEB number where nnode was written
 896 * @offs: offset where nnode was written
 897 *
 898 * This function is used by LPT garbage collection.  LPT garbage collection is
 899 * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
 900 * simply involves marking all the nodes in the LEB being garbage-collected as
 901 * dirty.  The dirty nodes are written next commit, after which the LEB is free
 902 * to be reused.
 903 *
 904 * This function returns %0 on success and a negative error code on failure.
 905 */
 906static int make_nnode_dirty(struct ubifs_info *c, int node_num, int lnum,
 907                            int offs)
 908{
 909        struct ubifs_nnode *nnode;
 910
 911        nnode = nnode_lookup(c, node_num);
 912        if (IS_ERR(nnode))
 913                return PTR_ERR(nnode);
 914        if (nnode->parent) {
 915                struct ubifs_nbranch *branch;
 916
 917                branch = &nnode->parent->nbranch[nnode->iip];
 918                if (branch->lnum != lnum || branch->offs != offs)
 919                        return 0; /* nnode is obsolete */
 920        } else if (c->lpt_lnum != lnum || c->lpt_offs != offs)
 921                        return 0; /* nnode is obsolete */
 922        /* Assumes cnext list is empty i.e. not called during commit */
 923        if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
 924                c->dirty_nn_cnt += 1;
 925                ubifs_add_nnode_dirt(c, nnode);
 926                /* Mark parent and ancestors dirty too */
 927                nnode = nnode->parent;
 928                while (nnode) {
 929                        if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
 930                                c->dirty_nn_cnt += 1;
 931                                ubifs_add_nnode_dirt(c, nnode);
 932                                nnode = nnode->parent;
 933                        } else
 934                                break;
 935                }
 936        }
 937        return 0;
 938}
 939
 940/**
 941 * make_pnode_dirty - find a pnode and, if found, make it dirty.
 942 * @c: UBIFS file-system description object
 943 * @node_num: pnode number of pnode to make dirty
 944 * @lnum: LEB number where pnode was written
 945 * @offs: offset where pnode was written
 946 *
 947 * This function is used by LPT garbage collection.  LPT garbage collection is
 948 * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
 949 * simply involves marking all the nodes in the LEB being garbage-collected as
 950 * dirty.  The dirty nodes are written next commit, after which the LEB is free
 951 * to be reused.
 952 *
 953 * This function returns %0 on success and a negative error code on failure.
 954 */
 955static int make_pnode_dirty(struct ubifs_info *c, int node_num, int lnum,
 956                            int offs)
 957{
 958        struct ubifs_pnode *pnode;
 959        struct ubifs_nbranch *branch;
 960
 961        pnode = pnode_lookup(c, node_num);
 962        if (IS_ERR(pnode))
 963                return PTR_ERR(pnode);
 964        branch = &pnode->parent->nbranch[pnode->iip];
 965        if (branch->lnum != lnum || branch->offs != offs)
 966                return 0;
 967        do_make_pnode_dirty(c, pnode);
 968        return 0;
 969}
 970
 971/**
 972 * make_ltab_dirty - make ltab node dirty.
 973 * @c: UBIFS file-system description object
 974 * @lnum: LEB number where ltab was written
 975 * @offs: offset where ltab was written
 976 *
 977 * This function is used by LPT garbage collection.  LPT garbage collection is
 978 * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
 979 * simply involves marking all the nodes in the LEB being garbage-collected as
 980 * dirty.  The dirty nodes are written next commit, after which the LEB is free
 981 * to be reused.
 982 *
 983 * This function returns %0 on success and a negative error code on failure.
 984 */
 985static int make_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
 986{
 987        if (lnum != c->ltab_lnum || offs != c->ltab_offs)
 988                return 0; /* This ltab node is obsolete */
 989        if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
 990                c->lpt_drty_flgs |= LTAB_DIRTY;
 991                ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
 992        }
 993        return 0;
 994}
 995
 996/**
 997 * make_lsave_dirty - make lsave node dirty.
 998 * @c: UBIFS file-system description object
 999 * @lnum: LEB number where lsave was written
1000 * @offs: offset where lsave was written
1001 *
1002 * This function is used by LPT garbage collection.  LPT garbage collection is
1003 * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
1004 * simply involves marking all the nodes in the LEB being garbage-collected as
1005 * dirty.  The dirty nodes are written next commit, after which the LEB is free
1006 * to be reused.
1007 *
1008 * This function returns %0 on success and a negative error code on failure.
1009 */
1010static int make_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
1011{
1012        if (lnum != c->lsave_lnum || offs != c->lsave_offs)
1013                return 0; /* This lsave node is obsolete */
1014        if (!(c->lpt_drty_flgs & LSAVE_DIRTY)) {
1015                c->lpt_drty_flgs |= LSAVE_DIRTY;
1016                ubifs_add_lpt_dirt(c, c->lsave_lnum, c->lsave_sz);
1017        }
1018        return 0;
1019}
1020
1021/**
1022 * make_node_dirty - make node dirty.
1023 * @c: UBIFS file-system description object
1024 * @node_type: LPT node type
1025 * @node_num: node number
1026 * @lnum: LEB number where node was written
1027 * @offs: offset where node was written
1028 *
1029 * This function is used by LPT garbage collection.  LPT garbage collection is
1030 * used only for the "big" LPT model (c->big_lpt == 1).  Garbage collection
1031 * simply involves marking all the nodes in the LEB being garbage-collected as
1032 * dirty.  The dirty nodes are written next commit, after which the LEB is free
1033 * to be reused.
1034 *
1035 * This function returns %0 on success and a negative error code on failure.
1036 */
1037static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num,
1038                           int lnum, int offs)
1039{
1040        switch (node_type) {
1041        case UBIFS_LPT_NNODE:
1042                return make_nnode_dirty(c, node_num, lnum, offs);
1043        case UBIFS_LPT_PNODE:
1044                return make_pnode_dirty(c, node_num, lnum, offs);
1045        case UBIFS_LPT_LTAB:
1046                return make_ltab_dirty(c, lnum, offs);
1047        case UBIFS_LPT_LSAVE:
1048                return make_lsave_dirty(c, lnum, offs);
1049        }
1050        return -EINVAL;
1051}
1052
1053/**
1054 * get_lpt_node_len - return the length of a node based on its type.
1055 * @c: UBIFS file-system description object
1056 * @node_type: LPT node type
1057 */
1058static int get_lpt_node_len(const struct ubifs_info *c, int node_type)
1059{
1060        switch (node_type) {
1061        case UBIFS_LPT_NNODE:
1062                return c->nnode_sz;
1063        case UBIFS_LPT_PNODE:
1064                return c->pnode_sz;
1065        case UBIFS_LPT_LTAB:
1066                return c->ltab_sz;
1067        case UBIFS_LPT_LSAVE:
1068                return c->lsave_sz;
1069        }
1070        return 0;
1071}
1072
1073/**
1074 * get_pad_len - return the length of padding in a buffer.
1075 * @c: UBIFS file-system description object
1076 * @buf: buffer
1077 * @len: length of buffer
1078 */
1079static int get_pad_len(const struct ubifs_info *c, uint8_t *buf, int len)
1080{
1081        int offs, pad_len;
1082
1083        if (c->min_io_size == 1)
1084                return 0;
1085        offs = c->leb_size - len;
1086        pad_len = ALIGN(offs, c->min_io_size) - offs;
1087        return pad_len;
1088}
1089
1090/**
1091 * get_lpt_node_type - return type (and node number) of a node in a buffer.
1092 * @c: UBIFS file-system description object
1093 * @buf: buffer
1094 * @node_num: node number is returned here
1095 */
1096static int get_lpt_node_type(const struct ubifs_info *c, uint8_t *buf,
1097                             int *node_num)
1098{
1099        uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1100        int pos = 0, node_type;
1101
1102        node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
1103        *node_num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
1104        return node_type;
1105}
1106
1107/**
1108 * is_a_node - determine if a buffer contains a node.
1109 * @c: UBIFS file-system description object
1110 * @buf: buffer
1111 * @len: length of buffer
1112 *
1113 * This function returns %1 if the buffer contains a node or %0 if it does not.
1114 */
1115static int is_a_node(const struct ubifs_info *c, uint8_t *buf, int len)
1116{
1117        uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1118        int pos = 0, node_type, node_len;
1119        uint16_t crc, calc_crc;
1120
1121        if (len < UBIFS_LPT_CRC_BYTES + (UBIFS_LPT_TYPE_BITS + 7) / 8)
1122                return 0;
1123        node_type = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_TYPE_BITS);
1124        if (node_type == UBIFS_LPT_NOT_A_NODE)
1125                return 0;
1126        node_len = get_lpt_node_len(c, node_type);
1127        if (!node_len || node_len > len)
1128                return 0;
1129        pos = 0;
1130        addr = buf;
1131        crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
1132        calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
1133                         node_len - UBIFS_LPT_CRC_BYTES);
1134        if (crc != calc_crc)
1135                return 0;
1136        return 1;
1137}
1138
1139/**
1140 * lpt_gc_lnum - garbage collect a LPT LEB.
1141 * @c: UBIFS file-system description object
1142 * @lnum: LEB number to garbage collect
1143 *
1144 * LPT garbage collection is used only for the "big" LPT model
1145 * (c->big_lpt == 1).  Garbage collection simply involves marking all the nodes
1146 * in the LEB being garbage-collected as dirty.  The dirty nodes are written
1147 * next commit, after which the LEB is free to be reused.
1148 *
1149 * This function returns %0 on success and a negative error code on failure.
1150 */
1151static int lpt_gc_lnum(struct ubifs_info *c, int lnum)
1152{
1153        int err, len = c->leb_size, node_type, node_num, node_len, offs;
1154        void *buf = c->lpt_buf;
1155
1156        dbg_lp("LEB %d", lnum);
1157
1158        err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1);
1159        if (err)
1160                return err;
1161
1162        while (1) {
1163                if (!is_a_node(c, buf, len)) {
1164                        int pad_len;
1165
1166                        pad_len = get_pad_len(c, buf, len);
1167                        if (pad_len) {
1168                                buf += pad_len;
1169                                len -= pad_len;
1170                                continue;
1171                        }
1172                        return 0;
1173                }
1174                node_type = get_lpt_node_type(c, buf, &node_num);
1175                node_len = get_lpt_node_len(c, node_type);
1176                offs = c->leb_size - len;
1177                ubifs_assert(node_len != 0);
1178                mutex_lock(&c->lp_mutex);
1179                err = make_node_dirty(c, node_type, node_num, lnum, offs);
1180                mutex_unlock(&c->lp_mutex);
1181                if (err)
1182                        return err;
1183                buf += node_len;
1184                len -= node_len;
1185        }
1186        return 0;
1187}
1188
1189/**
1190 * lpt_gc - LPT garbage collection.
1191 * @c: UBIFS file-system description object
1192 *
1193 * Select a LPT LEB for LPT garbage collection and call 'lpt_gc_lnum()'.
1194 * Returns %0 on success and a negative error code on failure.
1195 */
1196static int lpt_gc(struct ubifs_info *c)
1197{
1198        int i, lnum = -1, dirty = 0;
1199
1200        mutex_lock(&c->lp_mutex);
1201        for (i = 0; i < c->lpt_lebs; i++) {
1202                ubifs_assert(!c->ltab[i].tgc);
1203                if (i + c->lpt_first == c->nhead_lnum ||
1204                    c->ltab[i].free + c->ltab[i].dirty == c->leb_size)
1205                        continue;
1206                if (c->ltab[i].dirty > dirty) {
1207                        dirty = c->ltab[i].dirty;
1208                        lnum = i + c->lpt_first;
1209                }
1210        }
1211        mutex_unlock(&c->lp_mutex);
1212        if (lnum == -1)
1213                return -ENOSPC;
1214        return lpt_gc_lnum(c, lnum);
1215}
1216
1217/**
1218 * ubifs_lpt_start_commit - UBIFS commit starts.
1219 * @c: the UBIFS file-system description object
1220 *
1221 * This function has to be called when UBIFS starts the commit operation.
1222 * This function "freezes" all currently dirty LEB properties and does not
1223 * change them anymore. Further changes are saved and tracked separately
1224 * because they are not part of this commit. This function returns zero in case
1225 * of success and a negative error code in case of failure.
1226 */
1227int ubifs_lpt_start_commit(struct ubifs_info *c)
1228{
1229        int err, cnt;
1230
1231        dbg_lp("");
1232
1233        mutex_lock(&c->lp_mutex);
1234        err = dbg_chk_lpt_free_spc(c);
1235        if (err)
1236                goto out;
1237        err = dbg_check_ltab(c);
1238        if (err)
1239                goto out;
1240
1241        if (c->check_lpt_free) {
1242                /*
1243                 * We ensure there is enough free space in
1244                 * ubifs_lpt_post_commit() by marking nodes dirty. That
1245                 * information is lost when we unmount, so we also need
1246                 * to check free space once after mounting also.
1247                 */
1248                c->check_lpt_free = 0;
1249                while (need_write_all(c)) {
1250                        mutex_unlock(&c->lp_mutex);
1251                        err = lpt_gc(c);
1252                        if (err)
1253                                return err;
1254                        mutex_lock(&c->lp_mutex);
1255                }
1256        }
1257
1258        lpt_tgc_start(c);
1259
1260        if (!c->dirty_pn_cnt) {
1261                dbg_cmt("no cnodes to commit");
1262                err = 0;
1263                goto out;
1264        }
1265
1266        if (!c->big_lpt && need_write_all(c)) {
1267                /* If needed, write everything */
1268                err = make_tree_dirty(c);
1269                if (err)
1270                        goto out;
1271                lpt_tgc_start(c);
1272        }
1273
1274        if (c->big_lpt)
1275                populate_lsave(c);
1276
1277        cnt = get_cnodes_to_commit(c);
1278        ubifs_assert(cnt != 0);
1279
1280        err = layout_cnodes(c);
1281        if (err)
1282                goto out;
1283
1284        /* Copy the LPT's own lprops for end commit to write */
1285        memcpy(c->ltab_cmt, c->ltab,
1286               sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1287        c->lpt_drty_flgs &= ~(LTAB_DIRTY | LSAVE_DIRTY);
1288
1289out:
1290        mutex_unlock(&c->lp_mutex);
1291        return err;
1292}
1293
1294/**
1295 * free_obsolete_cnodes - free obsolete cnodes for commit end.
1296 * @c: UBIFS file-system description object
1297 */
1298static void free_obsolete_cnodes(struct ubifs_info *c)
1299{
1300        struct ubifs_cnode *cnode, *cnext;
1301
1302        cnext = c->lpt_cnext;
1303        if (!cnext)
1304                return;
1305        do {
1306                cnode = cnext;
1307                cnext = cnode->cnext;
1308                if (test_bit(OBSOLETE_CNODE, &cnode->flags))
1309                        kfree(cnode);
1310                else
1311                        cnode->cnext = NULL;
1312        } while (cnext != c->lpt_cnext);
1313        c->lpt_cnext = NULL;
1314}
1315
1316#ifndef __UBOOT__
1317/**
1318 * ubifs_lpt_end_commit - finish the commit operation.
1319 * @c: the UBIFS file-system description object
1320 *
1321 * This function has to be called when the commit operation finishes. It
1322 * flushes the changes which were "frozen" by 'ubifs_lprops_start_commit()' to
1323 * the media. Returns zero in case of success and a negative error code in case
1324 * of failure.
1325 */
1326int ubifs_lpt_end_commit(struct ubifs_info *c)
1327{
1328        int err;
1329
1330        dbg_lp("");
1331
1332        if (!c->lpt_cnext)
1333                return 0;
1334
1335        err = write_cnodes(c);
1336        if (err)
1337                return err;
1338
1339        mutex_lock(&c->lp_mutex);
1340        free_obsolete_cnodes(c);
1341        mutex_unlock(&c->lp_mutex);
1342
1343        return 0;
1344}
1345#endif
1346
1347/**
1348 * ubifs_lpt_post_commit - post commit LPT trivial GC and LPT GC.
1349 * @c: UBIFS file-system description object
1350 *
1351 * LPT trivial GC is completed after a commit. Also LPT GC is done after a
1352 * commit for the "big" LPT model.
1353 */
1354int ubifs_lpt_post_commit(struct ubifs_info *c)
1355{
1356        int err;
1357
1358        mutex_lock(&c->lp_mutex);
1359        err = lpt_tgc_end(c);
1360        if (err)
1361                goto out;
1362        if (c->big_lpt)
1363                while (need_write_all(c)) {
1364                        mutex_unlock(&c->lp_mutex);
1365                        err = lpt_gc(c);
1366                        if (err)
1367                                return err;
1368                        mutex_lock(&c->lp_mutex);
1369                }
1370out:
1371        mutex_unlock(&c->lp_mutex);
1372        return err;
1373}
1374
1375/**
1376 * first_nnode - find the first nnode in memory.
1377 * @c: UBIFS file-system description object
1378 * @hght: height of tree where nnode found is returned here
1379 *
1380 * This function returns a pointer to the nnode found or %NULL if no nnode is
1381 * found. This function is a helper to 'ubifs_lpt_free()'.
1382 */
1383static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght)
1384{
1385        struct ubifs_nnode *nnode;
1386        int h, i, found;
1387
1388        nnode = c->nroot;
1389        *hght = 0;
1390        if (!nnode)
1391                return NULL;
1392        for (h = 1; h < c->lpt_hght; h++) {
1393                found = 0;
1394                for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1395                        if (nnode->nbranch[i].nnode) {
1396                                found = 1;
1397                                nnode = nnode->nbranch[i].nnode;
1398                                *hght = h;
1399                                break;
1400                        }
1401                }
1402                if (!found)
1403                        break;
1404        }
1405        return nnode;
1406}
1407
1408/**
1409 * next_nnode - find the next nnode in memory.
1410 * @c: UBIFS file-system description object
1411 * @nnode: nnode from which to start.
1412 * @hght: height of tree where nnode is, is passed and returned here
1413 *
1414 * This function returns a pointer to the nnode found or %NULL if no nnode is
1415 * found. This function is a helper to 'ubifs_lpt_free()'.
1416 */
1417static struct ubifs_nnode *next_nnode(struct ubifs_info *c,
1418                                      struct ubifs_nnode *nnode, int *hght)
1419{
1420        struct ubifs_nnode *parent;
1421        int iip, h, i, found;
1422
1423        parent = nnode->parent;
1424        if (!parent)
1425                return NULL;
1426        if (nnode->iip == UBIFS_LPT_FANOUT - 1) {
1427                *hght -= 1;
1428                return parent;
1429        }
1430        for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
1431                nnode = parent->nbranch[iip].nnode;
1432                if (nnode)
1433                        break;
1434        }
1435        if (!nnode) {
1436                *hght -= 1;
1437                return parent;
1438        }
1439        for (h = *hght + 1; h < c->lpt_hght; h++) {
1440                found = 0;
1441                for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1442                        if (nnode->nbranch[i].nnode) {
1443                                found = 1;
1444                                nnode = nnode->nbranch[i].nnode;
1445                                *hght = h;
1446                                break;
1447                        }
1448                }
1449                if (!found)
1450                        break;
1451        }
1452        return nnode;
1453}
1454
1455/**
1456 * ubifs_lpt_free - free resources owned by the LPT.
1457 * @c: UBIFS file-system description object
1458 * @wr_only: free only resources used for writing
1459 */
1460void ubifs_lpt_free(struct ubifs_info *c, int wr_only)
1461{
1462        struct ubifs_nnode *nnode;
1463        int i, hght;
1464
1465        /* Free write-only things first */
1466
1467        free_obsolete_cnodes(c); /* Leftover from a failed commit */
1468
1469        vfree(c->ltab_cmt);
1470        c->ltab_cmt = NULL;
1471        vfree(c->lpt_buf);
1472        c->lpt_buf = NULL;
1473        kfree(c->lsave);
1474        c->lsave = NULL;
1475
1476        if (wr_only)
1477                return;
1478
1479        /* Now free the rest */
1480
1481        nnode = first_nnode(c, &hght);
1482        while (nnode) {
1483                for (i = 0; i < UBIFS_LPT_FANOUT; i++)
1484                        kfree(nnode->nbranch[i].nnode);
1485                nnode = next_nnode(c, nnode, &hght);
1486        }
1487        for (i = 0; i < LPROPS_HEAP_CNT; i++)
1488                kfree(c->lpt_heap[i].arr);
1489        kfree(c->dirty_idx.arr);
1490        kfree(c->nroot);
1491        vfree(c->ltab);
1492        kfree(c->lpt_nod_buf);
1493}
1494
1495#ifndef __UBOOT__
1496/*
1497 * Everything below is related to debugging.
1498 */
1499
1500/**
1501 * dbg_is_all_ff - determine if a buffer contains only 0xFF bytes.
1502 * @buf: buffer
1503 * @len: buffer length
1504 */
1505static int dbg_is_all_ff(uint8_t *buf, int len)
1506{
1507        int i;
1508
1509        for (i = 0; i < len; i++)
1510                if (buf[i] != 0xff)
1511                        return 0;
1512        return 1;
1513}
1514
1515/**
1516 * dbg_is_nnode_dirty - determine if a nnode is dirty.
1517 * @c: the UBIFS file-system description object
1518 * @lnum: LEB number where nnode was written
1519 * @offs: offset where nnode was written
1520 */
1521static int dbg_is_nnode_dirty(struct ubifs_info *c, int lnum, int offs)
1522{
1523        struct ubifs_nnode *nnode;
1524        int hght;
1525
1526        /* Entire tree is in memory so first_nnode / next_nnode are OK */
1527        nnode = first_nnode(c, &hght);
1528        for (; nnode; nnode = next_nnode(c, nnode, &hght)) {
1529                struct ubifs_nbranch *branch;
1530
1531                cond_resched();
1532                if (nnode->parent) {
1533                        branch = &nnode->parent->nbranch[nnode->iip];
1534                        if (branch->lnum != lnum || branch->offs != offs)
1535                                continue;
1536                        if (test_bit(DIRTY_CNODE, &nnode->flags))
1537                                return 1;
1538                        return 0;
1539                } else {
1540                        if (c->lpt_lnum != lnum || c->lpt_offs != offs)
1541                                continue;
1542                        if (test_bit(DIRTY_CNODE, &nnode->flags))
1543                                return 1;
1544                        return 0;
1545                }
1546        }
1547        return 1;
1548}
1549
1550/**
1551 * dbg_is_pnode_dirty - determine if a pnode is dirty.
1552 * @c: the UBIFS file-system description object
1553 * @lnum: LEB number where pnode was written
1554 * @offs: offset where pnode was written
1555 */
1556static int dbg_is_pnode_dirty(struct ubifs_info *c, int lnum, int offs)
1557{
1558        int i, cnt;
1559
1560        cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
1561        for (i = 0; i < cnt; i++) {
1562                struct ubifs_pnode *pnode;
1563                struct ubifs_nbranch *branch;
1564
1565                cond_resched();
1566                pnode = pnode_lookup(c, i);
1567                if (IS_ERR(pnode))
1568                        return PTR_ERR(pnode);
1569                branch = &pnode->parent->nbranch[pnode->iip];
1570                if (branch->lnum != lnum || branch->offs != offs)
1571                        continue;
1572                if (test_bit(DIRTY_CNODE, &pnode->flags))
1573                        return 1;
1574                return 0;
1575        }
1576        return 1;
1577}
1578
1579/**
1580 * dbg_is_ltab_dirty - determine if a ltab node is dirty.
1581 * @c: the UBIFS file-system description object
1582 * @lnum: LEB number where ltab node was written
1583 * @offs: offset where ltab node was written
1584 */
1585static int dbg_is_ltab_dirty(struct ubifs_info *c, int lnum, int offs)
1586{
1587        if (lnum != c->ltab_lnum || offs != c->ltab_offs)
1588                return 1;
1589        return (c->lpt_drty_flgs & LTAB_DIRTY) != 0;
1590}
1591
1592/**
1593 * dbg_is_lsave_dirty - determine if a lsave node is dirty.
1594 * @c: the UBIFS file-system description object
1595 * @lnum: LEB number where lsave node was written
1596 * @offs: offset where lsave node was written
1597 */
1598static int dbg_is_lsave_dirty(struct ubifs_info *c, int lnum, int offs)
1599{
1600        if (lnum != c->lsave_lnum || offs != c->lsave_offs)
1601                return 1;
1602        return (c->lpt_drty_flgs & LSAVE_DIRTY) != 0;
1603}
1604
1605/**
1606 * dbg_is_node_dirty - determine if a node is dirty.
1607 * @c: the UBIFS file-system description object
1608 * @node_type: node type
1609 * @lnum: LEB number where node was written
1610 * @offs: offset where node was written
1611 */
1612static int dbg_is_node_dirty(struct ubifs_info *c, int node_type, int lnum,
1613                             int offs)
1614{
1615        switch (node_type) {
1616        case UBIFS_LPT_NNODE:
1617                return dbg_is_nnode_dirty(c, lnum, offs);
1618        case UBIFS_LPT_PNODE:
1619                return dbg_is_pnode_dirty(c, lnum, offs);
1620        case UBIFS_LPT_LTAB:
1621                return dbg_is_ltab_dirty(c, lnum, offs);
1622        case UBIFS_LPT_LSAVE:
1623                return dbg_is_lsave_dirty(c, lnum, offs);
1624        }
1625        return 1;
1626}
1627
1628/**
1629 * dbg_check_ltab_lnum - check the ltab for a LPT LEB number.
1630 * @c: the UBIFS file-system description object
1631 * @lnum: LEB number where node was written
1632 * @offs: offset where node was written
1633 *
1634 * This function returns %0 on success and a negative error code on failure.
1635 */
1636static int dbg_check_ltab_lnum(struct ubifs_info *c, int lnum)
1637{
1638        int err, len = c->leb_size, dirty = 0, node_type, node_num, node_len;
1639        int ret;
1640        void *buf, *p;
1641
1642        if (!dbg_is_chk_lprops(c))
1643                return 0;
1644
1645        buf = p = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
1646        if (!buf) {
1647                ubifs_err(c, "cannot allocate memory for ltab checking");
1648                return 0;
1649        }
1650
1651        dbg_lp("LEB %d", lnum);
1652
1653        err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1);
1654        if (err)
1655                goto out;
1656
1657        while (1) {
1658                if (!is_a_node(c, p, len)) {
1659                        int i, pad_len;
1660
1661                        pad_len = get_pad_len(c, p, len);
1662                        if (pad_len) {
1663                                p += pad_len;
1664                                len -= pad_len;
1665                                dirty += pad_len;
1666                                continue;
1667                        }
1668                        if (!dbg_is_all_ff(p, len)) {
1669                                ubifs_err(c, "invalid empty space in LEB %d at %d",
1670                                          lnum, c->leb_size - len);
1671                                err = -EINVAL;
1672                        }
1673                        i = lnum - c->lpt_first;
1674                        if (len != c->ltab[i].free) {
1675                                ubifs_err(c, "invalid free space in LEB %d (free %d, expected %d)",
1676                                          lnum, len, c->ltab[i].free);
1677                                err = -EINVAL;
1678                        }
1679                        if (dirty != c->ltab[i].dirty) {
1680                                ubifs_err(c, "invalid dirty space in LEB %d (dirty %d, expected %d)",
1681                                          lnum, dirty, c->ltab[i].dirty);
1682                                err = -EINVAL;
1683                        }
1684                        goto out;
1685                }
1686                node_type = get_lpt_node_type(c, p, &node_num);
1687                node_len = get_lpt_node_len(c, node_type);
1688                ret = dbg_is_node_dirty(c, node_type, lnum, c->leb_size - len);
1689                if (ret == 1)
1690                        dirty += node_len;
1691                p += node_len;
1692                len -= node_len;
1693        }
1694
1695        err = 0;
1696out:
1697        vfree(buf);
1698        return err;
1699}
1700
1701/**
1702 * dbg_check_ltab - check the free and dirty space in the ltab.
1703 * @c: the UBIFS file-system description object
1704 *
1705 * This function returns %0 on success and a negative error code on failure.
1706 */
1707int dbg_check_ltab(struct ubifs_info *c)
1708{
1709        int lnum, err, i, cnt;
1710
1711        if (!dbg_is_chk_lprops(c))
1712                return 0;
1713
1714        /* Bring the entire tree into memory */
1715        cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
1716        for (i = 0; i < cnt; i++) {
1717                struct ubifs_pnode *pnode;
1718
1719                pnode = pnode_lookup(c, i);
1720                if (IS_ERR(pnode))
1721                        return PTR_ERR(pnode);
1722                cond_resched();
1723        }
1724
1725        /* Check nodes */
1726        err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)c->nroot, 0, 0);
1727        if (err)
1728                return err;
1729
1730        /* Check each LEB */
1731        for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) {
1732                err = dbg_check_ltab_lnum(c, lnum);
1733                if (err) {
1734                        ubifs_err(c, "failed at LEB %d", lnum);
1735                        return err;
1736                }
1737        }
1738
1739        dbg_lp("succeeded");
1740        return 0;
1741}
1742
1743/**
1744 * dbg_chk_lpt_free_spc - check LPT free space is enough to write entire LPT.
1745 * @c: the UBIFS file-system description object
1746 *
1747 * This function returns %0 on success and a negative error code on failure.
1748 */
1749int dbg_chk_lpt_free_spc(struct ubifs_info *c)
1750{
1751        long long free = 0;
1752        int i;
1753
1754        if (!dbg_is_chk_lprops(c))
1755                return 0;
1756
1757        for (i = 0; i < c->lpt_lebs; i++) {
1758                if (c->ltab[i].tgc || c->ltab[i].cmt)
1759                        continue;
1760                if (i + c->lpt_first == c->nhead_lnum)
1761                        free += c->leb_size - c->nhead_offs;
1762                else if (c->ltab[i].free == c->leb_size)
1763                        free += c->leb_size;
1764        }
1765        if (free < c->lpt_sz) {
1766                ubifs_err(c, "LPT space error: free %lld lpt_sz %lld",
1767                          free, c->lpt_sz);
1768                ubifs_dump_lpt_info(c);
1769                ubifs_dump_lpt_lebs(c);
1770                dump_stack();
1771                return -EINVAL;
1772        }
1773        return 0;
1774}
1775
1776/**
1777 * dbg_chk_lpt_sz - check LPT does not write more than LPT size.
1778 * @c: the UBIFS file-system description object
1779 * @action: what to do
1780 * @len: length written
1781 *
1782 * This function returns %0 on success and a negative error code on failure.
1783 * The @action argument may be one of:
1784 *   o %0 - LPT debugging checking starts, initialize debugging variables;
1785 *   o %1 - wrote an LPT node, increase LPT size by @len bytes;
1786 *   o %2 - switched to a different LEB and wasted @len bytes;
1787 *   o %3 - check that we've written the right number of bytes.
1788 *   o %4 - wasted @len bytes;
1789 */
1790int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
1791{
1792        struct ubifs_debug_info *d = c->dbg;
1793        long long chk_lpt_sz, lpt_sz;
1794        int err = 0;
1795
1796        if (!dbg_is_chk_lprops(c))
1797                return 0;
1798
1799        switch (action) {
1800        case 0:
1801                d->chk_lpt_sz = 0;
1802                d->chk_lpt_sz2 = 0;
1803                d->chk_lpt_lebs = 0;
1804                d->chk_lpt_wastage = 0;
1805                if (c->dirty_pn_cnt > c->pnode_cnt) {
1806                        ubifs_err(c, "dirty pnodes %d exceed max %d",
1807                                  c->dirty_pn_cnt, c->pnode_cnt);
1808                        err = -EINVAL;
1809                }
1810                if (c->dirty_nn_cnt > c->nnode_cnt) {
1811                        ubifs_err(c, "dirty nnodes %d exceed max %d",
1812                                  c->dirty_nn_cnt, c->nnode_cnt);
1813                        err = -EINVAL;
1814                }
1815                return err;
1816        case 1:
1817                d->chk_lpt_sz += len;
1818                return 0;
1819        case 2:
1820                d->chk_lpt_sz += len;
1821                d->chk_lpt_wastage += len;
1822                d->chk_lpt_lebs += 1;
1823                return 0;
1824        case 3:
1825                chk_lpt_sz = c->leb_size;
1826                chk_lpt_sz *= d->chk_lpt_lebs;
1827                chk_lpt_sz += len - c->nhead_offs;
1828                if (d->chk_lpt_sz != chk_lpt_sz) {
1829                        ubifs_err(c, "LPT wrote %lld but space used was %lld",
1830                                  d->chk_lpt_sz, chk_lpt_sz);
1831                        err = -EINVAL;
1832                }
1833                if (d->chk_lpt_sz > c->lpt_sz) {
1834                        ubifs_err(c, "LPT wrote %lld but lpt_sz is %lld",
1835                                  d->chk_lpt_sz, c->lpt_sz);
1836                        err = -EINVAL;
1837                }
1838                if (d->chk_lpt_sz2 && d->chk_lpt_sz != d->chk_lpt_sz2) {
1839                        ubifs_err(c, "LPT layout size %lld but wrote %lld",
1840                                  d->chk_lpt_sz, d->chk_lpt_sz2);
1841                        err = -EINVAL;
1842                }
1843                if (d->chk_lpt_sz2 && d->new_nhead_offs != len) {
1844                        ubifs_err(c, "LPT new nhead offs: expected %d was %d",
1845                                  d->new_nhead_offs, len);
1846                        err = -EINVAL;
1847                }
1848                lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
1849                lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
1850                lpt_sz += c->ltab_sz;
1851                if (c->big_lpt)
1852                        lpt_sz += c->lsave_sz;
1853                if (d->chk_lpt_sz - d->chk_lpt_wastage > lpt_sz) {
1854                        ubifs_err(c, "LPT chk_lpt_sz %lld + waste %lld exceeds %lld",
1855                                  d->chk_lpt_sz, d->chk_lpt_wastage, lpt_sz);
1856                        err = -EINVAL;
1857                }
1858                if (err) {
1859                        ubifs_dump_lpt_info(c);
1860                        ubifs_dump_lpt_lebs(c);
1861                        dump_stack();
1862                }
1863                d->chk_lpt_sz2 = d->chk_lpt_sz;
1864                d->chk_lpt_sz = 0;
1865                d->chk_lpt_wastage = 0;
1866                d->chk_lpt_lebs = 0;
1867                d->new_nhead_offs = len;
1868                return err;
1869        case 4:
1870                d->chk_lpt_sz += len;
1871                d->chk_lpt_wastage += len;
1872                return 0;
1873        default:
1874                return -EINVAL;
1875        }
1876}
1877
1878/**
1879 * ubifs_dump_lpt_leb - dump an LPT LEB.
1880 * @c: UBIFS file-system description object
1881 * @lnum: LEB number to dump
1882 *
1883 * This function dumps an LEB from LPT area. Nodes in this area are very
1884 * different to nodes in the main area (e.g., they do not have common headers,
1885 * they do not have 8-byte alignments, etc), so we have a separate function to
1886 * dump LPT area LEBs. Note, LPT has to be locked by the caller.
1887 */
1888static void dump_lpt_leb(const struct ubifs_info *c, int lnum)
1889{
1890        int err, len = c->leb_size, node_type, node_num, node_len, offs;
1891        void *buf, *p;
1892
1893        pr_err("(pid %d) start dumping LEB %d\n", current->pid, lnum);
1894        buf = p = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
1895        if (!buf) {
1896                ubifs_err(c, "cannot allocate memory to dump LPT");
1897                return;
1898        }
1899
1900        err = ubifs_leb_read(c, lnum, buf, 0, c->leb_size, 1);
1901        if (err)
1902                goto out;
1903
1904        while (1) {
1905                offs = c->leb_size - len;
1906                if (!is_a_node(c, p, len)) {
1907                        int pad_len;
1908
1909                        pad_len = get_pad_len(c, p, len);
1910                        if (pad_len) {
1911                                pr_err("LEB %d:%d, pad %d bytes\n",
1912                                       lnum, offs, pad_len);
1913                                p += pad_len;
1914                                len -= pad_len;
1915                                continue;
1916                        }
1917                        if (len)
1918                                pr_err("LEB %d:%d, free %d bytes\n",
1919                                       lnum, offs, len);
1920                        break;
1921                }
1922
1923                node_type = get_lpt_node_type(c, p, &node_num);
1924                switch (node_type) {
1925                case UBIFS_LPT_PNODE:
1926                {
1927                        node_len = c->pnode_sz;
1928                        if (c->big_lpt)
1929                                pr_err("LEB %d:%d, pnode num %d\n",
1930                                       lnum, offs, node_num);
1931                        else
1932                                pr_err("LEB %d:%d, pnode\n", lnum, offs);
1933                        break;
1934                }
1935                case UBIFS_LPT_NNODE:
1936                {
1937                        int i;
1938                        struct ubifs_nnode nnode;
1939
1940                        node_len = c->nnode_sz;
1941                        if (c->big_lpt)
1942                                pr_err("LEB %d:%d, nnode num %d, ",
1943                                       lnum, offs, node_num);
1944                        else
1945                                pr_err("LEB %d:%d, nnode, ",
1946                                       lnum, offs);
1947                        err = ubifs_unpack_nnode(c, p, &nnode);
1948                        if (err) {
1949                                pr_err("failed to unpack_node, error %d\n",
1950                                       err);
1951                                break;
1952                        }
1953                        for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1954                                pr_cont("%d:%d", nnode.nbranch[i].lnum,
1955                                       nnode.nbranch[i].offs);
1956                                if (i != UBIFS_LPT_FANOUT - 1)
1957                                        pr_cont(", ");
1958                        }
1959                        pr_cont("\n");
1960                        break;
1961                }
1962                case UBIFS_LPT_LTAB:
1963                        node_len = c->ltab_sz;
1964                        pr_err("LEB %d:%d, ltab\n", lnum, offs);
1965                        break;
1966                case UBIFS_LPT_LSAVE:
1967                        node_len = c->lsave_sz;
1968                        pr_err("LEB %d:%d, lsave len\n", lnum, offs);
1969                        break;
1970                default:
1971                        ubifs_err(c, "LPT node type %d not recognized", node_type);
1972                        goto out;
1973                }
1974
1975                p += node_len;
1976                len -= node_len;
1977        }
1978
1979        pr_err("(pid %d) finish dumping LEB %d\n", current->pid, lnum);
1980out:
1981        vfree(buf);
1982        return;
1983}
1984
1985/**
1986 * ubifs_dump_lpt_lebs - dump LPT lebs.
1987 * @c: UBIFS file-system description object
1988 *
1989 * This function dumps all LPT LEBs. The caller has to make sure the LPT is
1990 * locked.
1991 */
1992void ubifs_dump_lpt_lebs(const struct ubifs_info *c)
1993{
1994        int i;
1995
1996        pr_err("(pid %d) start dumping all LPT LEBs\n", current->pid);
1997        for (i = 0; i < c->lpt_lebs; i++)
1998                dump_lpt_leb(c, i + c->lpt_first);
1999        pr_err("(pid %d) finish dumping all LPT LEBs\n", current->pid);
2000}
2001
2002/**
2003 * dbg_populate_lsave - debugging version of 'populate_lsave()'
2004 * @c: UBIFS file-system description object
2005 *
2006 * This is a debugging version for 'populate_lsave()' which populates lsave
2007 * with random LEBs instead of useful LEBs, which is good for test coverage.
2008 * Returns zero if lsave has not been populated (this debugging feature is
2009 * disabled) an non-zero if lsave has been populated.
2010 */
2011static int dbg_populate_lsave(struct ubifs_info *c)
2012{
2013        struct ubifs_lprops *lprops;
2014        struct ubifs_lpt_heap *heap;
2015        int i;
2016
2017        if (!dbg_is_chk_gen(c))
2018                return 0;
2019        if (prandom_u32() & 3)
2020                return 0;
2021
2022        for (i = 0; i < c->lsave_cnt; i++)
2023                c->lsave[i] = c->main_first;
2024
2025        list_for_each_entry(lprops, &c->empty_list, list)
2026                c->lsave[prandom_u32() % c->lsave_cnt] = lprops->lnum;
2027        list_for_each_entry(lprops, &c->freeable_list, list)
2028                c->lsave[prandom_u32() % c->lsave_cnt] = lprops->lnum;
2029        list_for_each_entry(lprops, &c->frdi_idx_list, list)
2030                c->lsave[prandom_u32() % c->lsave_cnt] = lprops->lnum;
2031
2032        heap = &c->lpt_heap[LPROPS_DIRTY_IDX - 1];
2033        for (i = 0; i < heap->cnt; i++)
2034                c->lsave[prandom_u32() % c->lsave_cnt] = heap->arr[i]->lnum;
2035        heap = &c->lpt_heap[LPROPS_DIRTY - 1];
2036        for (i = 0; i < heap->cnt; i++)
2037                c->lsave[prandom_u32() % c->lsave_cnt] = heap->arr[i]->lnum;
2038        heap = &c->lpt_heap[LPROPS_FREE - 1];
2039        for (i = 0; i < heap->cnt; i++)
2040                c->lsave[prandom_u32() % c->lsave_cnt] = heap->arr[i]->lnum;
2041
2042        return 1;
2043}
2044#endif
2045