linux/fs/ubifs/debug.h
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   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#ifndef __UBIFS_DEBUG_H__
  24#define __UBIFS_DEBUG_H__
  25
  26#ifdef CONFIG_UBIFS_FS_DEBUG
  27
  28/**
  29 * ubifs_debug_info - per-FS debugging information.
  30 * @buf: a buffer of LEB size, used for various purposes
  31 * @old_zroot: old index root - used by 'dbg_check_old_index()'
  32 * @old_zroot_level: old index root level - used by 'dbg_check_old_index()'
  33 * @old_zroot_sqnum: old index root sqnum - used by 'dbg_check_old_index()'
  34 * @failure_mode: failure mode for recovery testing
  35 * @fail_delay: 0=>don't delay, 1=>delay a time, 2=>delay a number of calls
  36 * @fail_timeout: time in jiffies when delay of failure mode expires
  37 * @fail_cnt: current number of calls to failure mode I/O functions
  38 * @fail_cnt_max: number of calls by which to delay failure mode
  39 * @chk_lpt_sz: used by LPT tree size checker
  40 * @chk_lpt_sz2: used by LPT tree size checker
  41 * @chk_lpt_wastage: used by LPT tree size checker
  42 * @chk_lpt_lebs: used by LPT tree size checker
  43 * @new_nhead_offs: used by LPT tree size checker
  44 * @new_ihead_lnum: used by debugging to check @c->ihead_lnum
  45 * @new_ihead_offs: used by debugging to check @c->ihead_offs
  46 *
  47 * @saved_lst: saved lprops statistics (used by 'dbg_save_space_info()')
  48 * @saved_free: saved free space (used by 'dbg_save_space_info()')
  49 *
  50 * dfs_dir_name: name of debugfs directory containing this file-system's files
  51 * dfs_dir: direntry object of the file-system debugfs directory
  52 * dfs_dump_lprops: "dump lprops" debugfs knob
  53 * dfs_dump_budg: "dump budgeting information" debugfs knob
  54 * dfs_dump_tnc: "dump TNC" debugfs knob
  55 */
  56struct ubifs_debug_info {
  57        void *buf;
  58        struct ubifs_zbranch old_zroot;
  59        int old_zroot_level;
  60        unsigned long long old_zroot_sqnum;
  61        int failure_mode;
  62        int fail_delay;
  63        unsigned long fail_timeout;
  64        unsigned int fail_cnt;
  65        unsigned int fail_cnt_max;
  66        long long chk_lpt_sz;
  67        long long chk_lpt_sz2;
  68        long long chk_lpt_wastage;
  69        int chk_lpt_lebs;
  70        int new_nhead_offs;
  71        int new_ihead_lnum;
  72        int new_ihead_offs;
  73
  74        struct ubifs_lp_stats saved_lst;
  75        long long saved_free;
  76
  77        char dfs_dir_name[100];
  78        struct dentry *dfs_dir;
  79        struct dentry *dfs_dump_lprops;
  80        struct dentry *dfs_dump_budg;
  81        struct dentry *dfs_dump_tnc;
  82};
  83
  84#define ubifs_assert(expr) do {                                                \
  85        if (unlikely(!(expr))) {                                               \
  86                printk(KERN_CRIT "UBIFS assert failed in %s at %u (pid %d)\n", \
  87                       __func__, __LINE__, current->pid);                      \
  88                dbg_dump_stack();                                              \
  89        }                                                                      \
  90} while (0)
  91
  92#define ubifs_assert_cmt_locked(c) do {                                        \
  93        if (unlikely(down_write_trylock(&(c)->commit_sem))) {                  \
  94                up_write(&(c)->commit_sem);                                    \
  95                printk(KERN_CRIT "commit lock is not locked!\n");              \
  96                ubifs_assert(0);                                               \
  97        }                                                                      \
  98} while (0)
  99
 100#define dbg_dump_stack() do {                                                  \
 101        if (!dbg_failure_mode)                                                 \
 102                dump_stack();                                                  \
 103} while (0)
 104
 105/* Generic debugging messages */
 106#define dbg_msg(fmt, ...) do {                                                 \
 107        spin_lock(&dbg_lock);                                                  \
 108        printk(KERN_DEBUG "UBIFS DBG (pid %d): %s: " fmt "\n", current->pid,   \
 109               __func__, ##__VA_ARGS__);                                       \
 110        spin_unlock(&dbg_lock);                                                \
 111} while (0)
 112
 113#define dbg_do_msg(typ, fmt, ...) do {                                         \
 114        if (ubifs_msg_flags & typ)                                             \
 115                dbg_msg(fmt, ##__VA_ARGS__);                                   \
 116} while (0)
 117
 118#define dbg_err(fmt, ...) do {                                                 \
 119        spin_lock(&dbg_lock);                                                  \
 120        ubifs_err(fmt, ##__VA_ARGS__);                                         \
 121        spin_unlock(&dbg_lock);                                                \
 122} while (0)
 123
 124const char *dbg_key_str0(const struct ubifs_info *c,
 125                         const union ubifs_key *key);
 126const char *dbg_key_str1(const struct ubifs_info *c,
 127                         const union ubifs_key *key);
 128
 129/*
 130 * DBGKEY macros require @dbg_lock to be held, which it is in the dbg message
 131 * macros.
 132 */
 133#define DBGKEY(key) dbg_key_str0(c, (key))
 134#define DBGKEY1(key) dbg_key_str1(c, (key))
 135
 136/* General messages */
 137#define dbg_gen(fmt, ...)   dbg_do_msg(UBIFS_MSG_GEN, fmt, ##__VA_ARGS__)
 138
 139/* Additional journal messages */
 140#define dbg_jnl(fmt, ...)   dbg_do_msg(UBIFS_MSG_JNL, fmt, ##__VA_ARGS__)
 141
 142/* Additional TNC messages */
 143#define dbg_tnc(fmt, ...)   dbg_do_msg(UBIFS_MSG_TNC, fmt, ##__VA_ARGS__)
 144
 145/* Additional lprops messages */
 146#define dbg_lp(fmt, ...)    dbg_do_msg(UBIFS_MSG_LP, fmt, ##__VA_ARGS__)
 147
 148/* Additional LEB find messages */
 149#define dbg_find(fmt, ...)  dbg_do_msg(UBIFS_MSG_FIND, fmt, ##__VA_ARGS__)
 150
 151/* Additional mount messages */
 152#define dbg_mnt(fmt, ...)   dbg_do_msg(UBIFS_MSG_MNT, fmt, ##__VA_ARGS__)
 153
 154/* Additional I/O messages */
 155#define dbg_io(fmt, ...)    dbg_do_msg(UBIFS_MSG_IO, fmt, ##__VA_ARGS__)
 156
 157/* Additional commit messages */
 158#define dbg_cmt(fmt, ...)   dbg_do_msg(UBIFS_MSG_CMT, fmt, ##__VA_ARGS__)
 159
 160/* Additional budgeting messages */
 161#define dbg_budg(fmt, ...)  dbg_do_msg(UBIFS_MSG_BUDG, fmt, ##__VA_ARGS__)
 162
 163/* Additional log messages */
 164#define dbg_log(fmt, ...)   dbg_do_msg(UBIFS_MSG_LOG, fmt, ##__VA_ARGS__)
 165
 166/* Additional gc messages */
 167#define dbg_gc(fmt, ...)    dbg_do_msg(UBIFS_MSG_GC, fmt, ##__VA_ARGS__)
 168
 169/* Additional scan messages */
 170#define dbg_scan(fmt, ...)  dbg_do_msg(UBIFS_MSG_SCAN, fmt, ##__VA_ARGS__)
 171
 172/* Additional recovery messages */
 173#define dbg_rcvry(fmt, ...) dbg_do_msg(UBIFS_MSG_RCVRY, fmt, ##__VA_ARGS__)
 174
 175/*
 176 * Debugging message type flags (must match msg_type_names in debug.c).
 177 *
 178 * UBIFS_MSG_GEN: general messages
 179 * UBIFS_MSG_JNL: journal messages
 180 * UBIFS_MSG_MNT: mount messages
 181 * UBIFS_MSG_CMT: commit messages
 182 * UBIFS_MSG_FIND: LEB find messages
 183 * UBIFS_MSG_BUDG: budgeting messages
 184 * UBIFS_MSG_GC: garbage collection messages
 185 * UBIFS_MSG_TNC: TNC messages
 186 * UBIFS_MSG_LP: lprops messages
 187 * UBIFS_MSG_IO: I/O messages
 188 * UBIFS_MSG_LOG: log messages
 189 * UBIFS_MSG_SCAN: scan messages
 190 * UBIFS_MSG_RCVRY: recovery messages
 191 */
 192enum {
 193        UBIFS_MSG_GEN   = 0x1,
 194        UBIFS_MSG_JNL   = 0x2,
 195        UBIFS_MSG_MNT   = 0x4,
 196        UBIFS_MSG_CMT   = 0x8,
 197        UBIFS_MSG_FIND  = 0x10,
 198        UBIFS_MSG_BUDG  = 0x20,
 199        UBIFS_MSG_GC    = 0x40,
 200        UBIFS_MSG_TNC   = 0x80,
 201        UBIFS_MSG_LP    = 0x100,
 202        UBIFS_MSG_IO    = 0x200,
 203        UBIFS_MSG_LOG   = 0x400,
 204        UBIFS_MSG_SCAN  = 0x800,
 205        UBIFS_MSG_RCVRY = 0x1000,
 206};
 207
 208/* Debugging message type flags for each default debug message level */
 209#define UBIFS_MSG_LVL_0 0
 210#define UBIFS_MSG_LVL_1 0x1
 211#define UBIFS_MSG_LVL_2 0x7f
 212#define UBIFS_MSG_LVL_3 0xffff
 213
 214/*
 215 * Debugging check flags (must match chk_names in debug.c).
 216 *
 217 * UBIFS_CHK_GEN: general checks
 218 * UBIFS_CHK_TNC: check TNC
 219 * UBIFS_CHK_IDX_SZ: check index size
 220 * UBIFS_CHK_ORPH: check orphans
 221 * UBIFS_CHK_OLD_IDX: check the old index
 222 * UBIFS_CHK_LPROPS: check lprops
 223 * UBIFS_CHK_FS: check the file-system
 224 */
 225enum {
 226        UBIFS_CHK_GEN     = 0x1,
 227        UBIFS_CHK_TNC     = 0x2,
 228        UBIFS_CHK_IDX_SZ  = 0x4,
 229        UBIFS_CHK_ORPH    = 0x8,
 230        UBIFS_CHK_OLD_IDX = 0x10,
 231        UBIFS_CHK_LPROPS  = 0x20,
 232        UBIFS_CHK_FS      = 0x40,
 233};
 234
 235/*
 236 * Special testing flags (must match tst_names in debug.c).
 237 *
 238 * UBIFS_TST_FORCE_IN_THE_GAPS: force the use of in-the-gaps method
 239 * UBIFS_TST_RCVRY: failure mode for recovery testing
 240 */
 241enum {
 242        UBIFS_TST_FORCE_IN_THE_GAPS = 0x2,
 243        UBIFS_TST_RCVRY             = 0x4,
 244};
 245
 246#if CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 1
 247#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_1
 248#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 2
 249#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_2
 250#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 3
 251#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_3
 252#else
 253#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_0
 254#endif
 255
 256#ifdef CONFIG_UBIFS_FS_DEBUG_CHKS
 257#define UBIFS_CHK_FLAGS_DEFAULT 0xffffffff
 258#else
 259#define UBIFS_CHK_FLAGS_DEFAULT 0
 260#endif
 261
 262extern spinlock_t dbg_lock;
 263
 264extern unsigned int ubifs_msg_flags;
 265extern unsigned int ubifs_chk_flags;
 266extern unsigned int ubifs_tst_flags;
 267
 268int ubifs_debugging_init(struct ubifs_info *c);
 269void ubifs_debugging_exit(struct ubifs_info *c);
 270
 271/* Dump functions */
 272const char *dbg_ntype(int type);
 273const char *dbg_cstate(int cmt_state);
 274const char *dbg_get_key_dump(const struct ubifs_info *c,
 275                             const union ubifs_key *key);
 276void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode);
 277void dbg_dump_node(const struct ubifs_info *c, const void *node);
 278void dbg_dump_lpt_node(const struct ubifs_info *c, void *node, int lnum,
 279                       int offs);
 280void dbg_dump_budget_req(const struct ubifs_budget_req *req);
 281void dbg_dump_lstats(const struct ubifs_lp_stats *lst);
 282void dbg_dump_budg(struct ubifs_info *c);
 283void dbg_dump_lprop(const struct ubifs_info *c, const struct ubifs_lprops *lp);
 284void dbg_dump_lprops(struct ubifs_info *c);
 285void dbg_dump_lpt_info(struct ubifs_info *c);
 286void dbg_dump_leb(const struct ubifs_info *c, int lnum);
 287void dbg_dump_znode(const struct ubifs_info *c,
 288                    const struct ubifs_znode *znode);
 289void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat);
 290void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
 291                    struct ubifs_nnode *parent, int iip);
 292void dbg_dump_tnc(struct ubifs_info *c);
 293void dbg_dump_index(struct ubifs_info *c);
 294void dbg_dump_lpt_lebs(const struct ubifs_info *c);
 295
 296/* Checking helper functions */
 297typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
 298                                 struct ubifs_zbranch *zbr, void *priv);
 299typedef int (*dbg_znode_callback)(struct ubifs_info *c,
 300                                  struct ubifs_znode *znode, void *priv);
 301int dbg_walk_index(struct ubifs_info *c, dbg_leaf_callback leaf_cb,
 302                   dbg_znode_callback znode_cb, void *priv);
 303
 304/* Checking functions */
 305void dbg_save_space_info(struct ubifs_info *c);
 306int dbg_check_space_info(struct ubifs_info *c);
 307int dbg_check_lprops(struct ubifs_info *c);
 308int dbg_old_index_check_init(struct ubifs_info *c, struct ubifs_zbranch *zroot);
 309int dbg_check_old_index(struct ubifs_info *c, struct ubifs_zbranch *zroot);
 310int dbg_check_cats(struct ubifs_info *c);
 311int dbg_check_ltab(struct ubifs_info *c);
 312int dbg_chk_lpt_free_spc(struct ubifs_info *c);
 313int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len);
 314int dbg_check_synced_i_size(struct inode *inode);
 315int dbg_check_dir_size(struct ubifs_info *c, const struct inode *dir);
 316int dbg_check_tnc(struct ubifs_info *c, int extra);
 317int dbg_check_idx_size(struct ubifs_info *c, long long idx_size);
 318int dbg_check_filesystem(struct ubifs_info *c);
 319void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
 320                    int add_pos);
 321int dbg_check_lprops(struct ubifs_info *c);
 322int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
 323                        int row, int col);
 324
 325/* Force the use of in-the-gaps method for testing */
 326
 327#define dbg_force_in_the_gaps_enabled \
 328        (ubifs_tst_flags & UBIFS_TST_FORCE_IN_THE_GAPS)
 329
 330int dbg_force_in_the_gaps(void);
 331
 332/* Failure mode for recovery testing */
 333
 334#define dbg_failure_mode (ubifs_tst_flags & UBIFS_TST_RCVRY)
 335
 336#ifndef UBIFS_DBG_PRESERVE_UBI
 337
 338#define ubi_leb_read   dbg_leb_read
 339#define ubi_leb_write  dbg_leb_write
 340#define ubi_leb_change dbg_leb_change
 341#define ubi_leb_erase  dbg_leb_erase
 342#define ubi_leb_unmap  dbg_leb_unmap
 343#define ubi_is_mapped  dbg_is_mapped
 344#define ubi_leb_map    dbg_leb_map
 345
 346#endif
 347
 348int dbg_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,
 349                 int len, int check);
 350int dbg_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
 351                  int offset, int len, int dtype);
 352int dbg_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
 353                   int len, int dtype);
 354int dbg_leb_erase(struct ubi_volume_desc *desc, int lnum);
 355int dbg_leb_unmap(struct ubi_volume_desc *desc, int lnum);
 356int dbg_is_mapped(struct ubi_volume_desc *desc, int lnum);
 357int dbg_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype);
 358
 359static inline int dbg_read(struct ubi_volume_desc *desc, int lnum, char *buf,
 360                           int offset, int len)
 361{
 362        return dbg_leb_read(desc, lnum, buf, offset, len, 0);
 363}
 364
 365static inline int dbg_write(struct ubi_volume_desc *desc, int lnum,
 366                            const void *buf, int offset, int len)
 367{
 368        return dbg_leb_write(desc, lnum, buf, offset, len, UBI_UNKNOWN);
 369}
 370
 371static inline int dbg_change(struct ubi_volume_desc *desc, int lnum,
 372                                    const void *buf, int len)
 373{
 374        return dbg_leb_change(desc, lnum, buf, len, UBI_UNKNOWN);
 375}
 376
 377/* Debugfs-related stuff */
 378int dbg_debugfs_init(void);
 379void dbg_debugfs_exit(void);
 380int dbg_debugfs_init_fs(struct ubifs_info *c);
 381void dbg_debugfs_exit_fs(struct ubifs_info *c);
 382
 383#else /* !CONFIG_UBIFS_FS_DEBUG */
 384
 385/* Use "if (0)" to make compiler check arguments even if debugging is off */
 386#define ubifs_assert(expr)  do {                                               \
 387        if (0 && (expr))                                                       \
 388                printk(KERN_CRIT "UBIFS assert failed in %s at %u (pid %d)\n", \
 389                       __func__, __LINE__, current->pid);                      \
 390} while (0)
 391
 392#define dbg_err(fmt, ...)   do {                                               \
 393        if (0)                                                                 \
 394                ubifs_err(fmt, ##__VA_ARGS__);                                 \
 395} while (0)
 396
 397#define dbg_msg(fmt, ...) do {                                                 \
 398        if (0)                                                                 \
 399                printk(KERN_DEBUG "UBIFS DBG (pid %d): %s: " fmt "\n",         \
 400                       current->pid, __func__, ##__VA_ARGS__);                 \
 401} while (0)
 402
 403#define dbg_dump_stack()
 404#define ubifs_assert_cmt_locked(c)
 405
 406#define dbg_gen(fmt, ...)   dbg_msg(fmt, ##__VA_ARGS__)
 407#define dbg_jnl(fmt, ...)   dbg_msg(fmt, ##__VA_ARGS__)
 408#define dbg_tnc(fmt, ...)   dbg_msg(fmt, ##__VA_ARGS__)
 409#define dbg_lp(fmt, ...)    dbg_msg(fmt, ##__VA_ARGS__)
 410#define dbg_find(fmt, ...)  dbg_msg(fmt, ##__VA_ARGS__)
 411#define dbg_mnt(fmt, ...)   dbg_msg(fmt, ##__VA_ARGS__)
 412#define dbg_io(fmt, ...)    dbg_msg(fmt, ##__VA_ARGS__)
 413#define dbg_cmt(fmt, ...)   dbg_msg(fmt, ##__VA_ARGS__)
 414#define dbg_budg(fmt, ...)  dbg_msg(fmt, ##__VA_ARGS__)
 415#define dbg_log(fmt, ...)   dbg_msg(fmt, ##__VA_ARGS__)
 416#define dbg_gc(fmt, ...)    dbg_msg(fmt, ##__VA_ARGS__)
 417#define dbg_scan(fmt, ...)  dbg_msg(fmt, ##__VA_ARGS__)
 418#define dbg_rcvry(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
 419
 420#define DBGKEY(key)  ((char *)(key))
 421#define DBGKEY1(key) ((char *)(key))
 422
 423#define ubifs_debugging_init(c)                0
 424#define ubifs_debugging_exit(c)                ({})
 425
 426#define dbg_ntype(type)                        ""
 427#define dbg_cstate(cmt_state)                  ""
 428#define dbg_get_key_dump(c, key)               ({})
 429#define dbg_dump_inode(c, inode)               ({})
 430#define dbg_dump_node(c, node)                 ({})
 431#define dbg_dump_lpt_node(c, node, lnum, offs) ({})
 432#define dbg_dump_budget_req(req)               ({})
 433#define dbg_dump_lstats(lst)                   ({})
 434#define dbg_dump_budg(c)                       ({})
 435#define dbg_dump_lprop(c, lp)                  ({})
 436#define dbg_dump_lprops(c)                     ({})
 437#define dbg_dump_lpt_info(c)                   ({})
 438#define dbg_dump_leb(c, lnum)                  ({})
 439#define dbg_dump_znode(c, znode)               ({})
 440#define dbg_dump_heap(c, heap, cat)            ({})
 441#define dbg_dump_pnode(c, pnode, parent, iip)  ({})
 442#define dbg_dump_tnc(c)                        ({})
 443#define dbg_dump_index(c)                      ({})
 444#define dbg_dump_lpt_lebs(c)                   ({})
 445
 446#define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0
 447#define dbg_old_index_check_init(c, zroot)         0
 448#define dbg_save_space_info(c)                     ({})
 449#define dbg_check_space_info(c)                    0
 450#define dbg_check_old_index(c, zroot)              0
 451#define dbg_check_cats(c)                          0
 452#define dbg_check_ltab(c)                          0
 453#define dbg_chk_lpt_free_spc(c)                    0
 454#define dbg_chk_lpt_sz(c, action, len)             0
 455#define dbg_check_synced_i_size(inode)             0
 456#define dbg_check_dir_size(c, dir)                 0
 457#define dbg_check_tnc(c, x)                        0
 458#define dbg_check_idx_size(c, idx_size)            0
 459#define dbg_check_filesystem(c)                    0
 460#define dbg_check_heap(c, heap, cat, add_pos)      ({})
 461#define dbg_check_lprops(c)                        0
 462#define dbg_check_lpt_nodes(c, cnode, row, col)    0
 463#define dbg_force_in_the_gaps_enabled              0
 464#define dbg_force_in_the_gaps()                    0
 465#define dbg_failure_mode                           0
 466
 467#define dbg_debugfs_init()                         0
 468#define dbg_debugfs_exit()
 469#define dbg_debugfs_init_fs(c)                     0
 470#define dbg_debugfs_exit_fs(c)                     0
 471
 472#endif /* !CONFIG_UBIFS_FS_DEBUG */
 473#endif /* !__UBIFS_DEBUG_H__ */
 474
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