1 // SPDX-License-Identifier: GPL-2.0 2 3 #include "fs.h" 4 #include "messages.h" 5 #include "discard.h" 6 #include "super.h" 7 8 #ifdef CONFIG_PRINTK 9 10 #define STATE_STRING_PREFACE " state " 11 #define STATE_STRING_BUF_LEN (sizeof(STATE_STRING_PREFACE) + BTRFS_FS_STATE_COUNT + 1) 12 13 /* 14 * Characters to print to indicate error conditions or uncommon filesystem state. 15 * RO is not an error. 16 */ 17 static const char fs_state_chars[] = { 18 [BTRFS_FS_STATE_REMOUNTING] = 'M', 19 [BTRFS_FS_STATE_RO] = 0, 20 [BTRFS_FS_STATE_TRANS_ABORTED] = 'A', 21 [BTRFS_FS_STATE_LOG_REPLAY_ABORTED] = 'O', 22 [BTRFS_FS_STATE_DEV_REPLACING] = 'R', 23 [BTRFS_FS_STATE_DUMMY_FS_INFO] = 0, 24 [BTRFS_FS_STATE_NO_DATA_CSUMS] = 'C', 25 [BTRFS_FS_STATE_SKIP_META_CSUMS] = 'S', 26 [BTRFS_FS_STATE_LOG_CLEANUP_ERROR] = 'L', 27 [BTRFS_FS_STATE_EMERGENCY_SHUTDOWN] = 'E', 28 }; 29 30 static void btrfs_state_to_string(const struct btrfs_fs_info *info, char *buf) 31 { 32 unsigned int bit; 33 bool states_printed = false; 34 unsigned long fs_state = READ_ONCE(info->fs_state); 35 char *curr = buf; 36 37 memcpy(curr, STATE_STRING_PREFACE, sizeof(STATE_STRING_PREFACE)); 38 curr += sizeof(STATE_STRING_PREFACE) - 1; 39 40 if (BTRFS_FS_ERROR(info)) { 41 *curr++ = 'E'; 42 states_printed = true; 43 } 44 45 for_each_set_bit(bit, &fs_state, sizeof(fs_state)) { 46 WARN_ON_ONCE(bit >= BTRFS_FS_STATE_COUNT); 47 if ((bit < BTRFS_FS_STATE_COUNT) && fs_state_chars[bit]) { 48 *curr++ = fs_state_chars[bit]; 49 states_printed = true; 50 } 51 } 52 53 /* If no states were printed, reset the buffer */ 54 if (!states_printed) 55 curr = buf; 56 57 *curr++ = 0; 58 } 59 #endif 60 61 /* 62 * Generally the error codes correspond to their respective errors, but there 63 * are a few special cases. 64 * 65 * EUCLEAN: Any sort of corruption that we encounter. The tree-checker for 66 * instance will return EUCLEAN if any of the blocks are corrupted in 67 * a way that is problematic. We want to reserve EUCLEAN for these 68 * sort of corruptions. 69 * 70 * EROFS: If we check BTRFS_FS_STATE_ERROR and fail out with a return error, we 71 * need to use EROFS for this case. We will have no idea of the 72 * original failure, that will have been reported at the time we tripped 73 * over the error. Each subsequent error that doesn't have any context 74 * of the original error should use EROFS when handling BTRFS_FS_STATE_ERROR. 75 */ 76 const char * __attribute_const__ btrfs_decode_error(int error) 77 { 78 char *errstr = "unknown"; 79 80 switch (error) { 81 case -ENOENT: /* -2 */ 82 errstr = "No such entry"; 83 break; 84 case -EIO: /* -5 */ 85 errstr = "IO failure"; 86 break; 87 case -ENOMEM: /* -12*/ 88 errstr = "Out of memory"; 89 break; 90 case -EEXIST: /* -17 */ 91 errstr = "Object already exists"; 92 break; 93 case -ENOSPC: /* -28 */ 94 errstr = "No space left"; 95 break; 96 case -EROFS: /* -30 */ 97 errstr = "Readonly filesystem"; 98 break; 99 case -EOPNOTSUPP: /* -95 */ 100 errstr = "Operation not supported"; 101 break; 102 case -EUCLEAN: /* -117 */ 103 errstr = "Filesystem corrupted"; 104 break; 105 case -EDQUOT: /* -122 */ 106 errstr = "Quota exceeded"; 107 break; 108 } 109 110 return errstr; 111 } 112 113 /* 114 * Decodes expected errors from the caller and invokes the appropriate error 115 * response. 116 */ 117 __cold 118 void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function, 119 unsigned int line, int error, const char *fmt, ...) 120 { 121 struct super_block *sb = fs_info->sb; 122 #ifdef CONFIG_PRINTK 123 char statestr[STATE_STRING_BUF_LEN]; 124 const char *errstr; 125 #endif 126 127 #ifdef CONFIG_PRINTK_INDEX 128 printk_index_subsys_emit( 129 "BTRFS: error (device %s%s) in %s:%d: errno=%d %s", KERN_CRIT, fmt); 130 #endif 131 132 /* 133 * Special case: if the error is EROFS, and we're already under 134 * SB_RDONLY, then it is safe here. 135 */ 136 if (error == -EROFS && sb_rdonly(sb)) 137 return; 138 139 #ifdef CONFIG_PRINTK 140 errstr = btrfs_decode_error(error); 141 btrfs_state_to_string(fs_info, statestr); 142 if (fmt) { 143 struct va_format vaf; 144 va_list args; 145 146 va_start(args, fmt); 147 vaf.fmt = fmt; 148 vaf.va = &args; 149 150 pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s (%pV)\n", 151 sb->s_id, statestr, function, line, error, errstr, &vaf); 152 va_end(args); 153 } else { 154 pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s\n", 155 sb->s_id, statestr, function, line, error, errstr); 156 } 157 #endif 158 159 /* 160 * Today we only save the error info to memory. Long term we'll also 161 * send it down to the disk. 162 */ 163 WRITE_ONCE(fs_info->fs_error, error); 164 165 /* Don't go through full error handling during mount. */ 166 if (!(sb->s_flags & SB_BORN)) 167 return; 168 169 if (sb_rdonly(sb)) 170 return; 171 172 btrfs_discard_stop(fs_info); 173 174 /* Handle error by forcing the filesystem readonly. */ 175 btrfs_set_sb_rdonly(sb); 176 btrfs_info(fs_info, "forced readonly"); 177 /* 178 * Note that a running device replace operation is not canceled here 179 * although there is no way to update the progress. It would add the 180 * risk of a deadlock, therefore the canceling is omitted. The only 181 * penalty is that some I/O remains active until the procedure 182 * completes. The next time when the filesystem is mounted writable 183 * again, the device replace operation continues. 184 */ 185 } 186 187 #ifdef CONFIG_PRINTK 188 static const char * const logtypes[] = { 189 "emergency", 190 "alert", 191 "critical", 192 "error", 193 "warning", 194 "notice", 195 "info", 196 "debug", 197 }; 198 199 /* 200 * Use one ratelimit state per log level so that a flood of less important 201 * messages doesn't cause more important ones to be dropped. 202 */ 203 static struct ratelimit_state printk_limits[] = { 204 RATELIMIT_STATE_INIT(printk_limits[0], DEFAULT_RATELIMIT_INTERVAL, 100), 205 RATELIMIT_STATE_INIT(printk_limits[1], DEFAULT_RATELIMIT_INTERVAL, 100), 206 RATELIMIT_STATE_INIT(printk_limits[2], DEFAULT_RATELIMIT_INTERVAL, 100), 207 RATELIMIT_STATE_INIT(printk_limits[3], DEFAULT_RATELIMIT_INTERVAL, 100), 208 RATELIMIT_STATE_INIT(printk_limits[4], DEFAULT_RATELIMIT_INTERVAL, 100), 209 RATELIMIT_STATE_INIT(printk_limits[5], DEFAULT_RATELIMIT_INTERVAL, 100), 210 RATELIMIT_STATE_INIT(printk_limits[6], DEFAULT_RATELIMIT_INTERVAL, 100), 211 RATELIMIT_STATE_INIT(printk_limits[7], DEFAULT_RATELIMIT_INTERVAL, 100), 212 }; 213 214 void __cold _btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...) 215 { 216 char lvl[PRINTK_MAX_SINGLE_HEADER_LEN + 1] = "\0"; 217 struct va_format vaf; 218 va_list args; 219 int kern_level; 220 const char *type = logtypes[4]; 221 struct ratelimit_state *ratelimit = &printk_limits[4]; 222 223 #ifdef CONFIG_PRINTK_INDEX 224 printk_index_subsys_emit("%sBTRFS %s (device %s): ", NULL, fmt); 225 #endif 226 227 va_start(args, fmt); 228 229 while ((kern_level = printk_get_level(fmt)) != 0) { 230 size_t size = printk_skip_level(fmt) - fmt; 231 232 if (kern_level >= '0' && kern_level <= '7') { 233 memcpy(lvl, fmt, size); 234 lvl[size] = '\0'; 235 type = logtypes[kern_level - '0']; 236 ratelimit = &printk_limits[kern_level - '0']; 237 } 238 fmt += size; 239 } 240 241 vaf.fmt = fmt; 242 vaf.va = &args; 243 244 /* Do not ratelimit if CONFIG_BTRFS_DEBUG is enabled. */ 245 if (IS_ENABLED(CONFIG_BTRFS_DEBUG) || __ratelimit(ratelimit)) { 246 if (fs_info) { 247 char statestr[STATE_STRING_BUF_LEN]; 248 249 btrfs_state_to_string(fs_info, statestr); 250 _printk("%sBTRFS %s (device %s%s): %pV\n", lvl, type, 251 fs_info->sb->s_id, statestr, &vaf); 252 } else { 253 _printk("%sBTRFS %s: %pV\n", lvl, type, &vaf); 254 } 255 } 256 257 va_end(args); 258 } 259 #endif 260 261 #if BITS_PER_LONG == 32 262 void __cold btrfs_warn_32bit_limit(struct btrfs_fs_info *fs_info) 263 { 264 if (!test_and_set_bit(BTRFS_FS_32BIT_WARN, &fs_info->flags)) { 265 btrfs_warn(fs_info, "reaching 32bit limit for logical addresses"); 266 btrfs_warn(fs_info, 267 "due to page cache limit on 32bit systems, btrfs can't access metadata at or beyond %lluT", 268 BTRFS_32BIT_MAX_FILE_SIZE >> 40); 269 btrfs_warn(fs_info, 270 "please consider upgrading to 64bit kernel/hardware"); 271 } 272 } 273 274 void __cold btrfs_err_32bit_limit(struct btrfs_fs_info *fs_info) 275 { 276 if (!test_and_set_bit(BTRFS_FS_32BIT_ERROR, &fs_info->flags)) { 277 btrfs_err(fs_info, "reached 32bit limit for logical addresses"); 278 btrfs_err(fs_info, 279 "due to page cache limit on 32bit systems, metadata beyond %lluT can't be accessed", 280 BTRFS_32BIT_MAX_FILE_SIZE >> 40); 281 btrfs_err(fs_info, 282 "please consider upgrading to 64bit kernel/hardware"); 283 } 284 } 285 #endif 286 287 /* 288 * Decode unexpected, fatal errors from the caller, issue an alert, and either 289 * panic or BUGs, depending on mount options. 290 */ 291 __cold 292 void __btrfs_panic(const struct btrfs_fs_info *fs_info, const char *function, 293 unsigned int line, int error, const char *fmt, ...) 294 { 295 char *s_id = "<unknown>"; 296 const char *errstr; 297 struct va_format vaf = { .fmt = fmt }; 298 va_list args; 299 300 if (fs_info) 301 s_id = fs_info->sb->s_id; 302 303 va_start(args, fmt); 304 vaf.va = &args; 305 306 errstr = btrfs_decode_error(error); 307 if (fs_info && (btrfs_test_opt(fs_info, PANIC_ON_FATAL_ERROR))) 308 panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (errno=%d %s)\n", 309 s_id, function, line, &vaf, error, errstr); 310 311 btrfs_crit(fs_info, "panic in %s:%d: %pV (errno=%d %s)", 312 function, line, &vaf, error, errstr); 313 va_end(args); 314 /* Caller calls BUG() */ 315 } 316