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