1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Interface between ext4 and JBD 4 */ 5 6 #include "ext4_jbd2.h" 7 8 #include <trace/events/ext4.h> 9 10 int ext4_inode_journal_mode(struct inode *inode) 11 { 12 if (EXT4_JOURNAL(inode) == NULL) 13 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 14 /* We do not support data journalling with delayed allocation */ 15 if (!S_ISREG(inode->i_mode) || 16 ext4_test_inode_flag(inode, EXT4_INODE_EA_INODE) || 17 test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || 18 (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) && 19 !test_opt(inode->i_sb, DELALLOC) && 20 !mapping_large_folio_support(inode->i_mapping))) { 21 /* We do not support data journalling for encrypted data */ 22 if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode)) 23 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 24 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 25 } 26 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 27 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 28 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 29 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 30 BUG(); 31 } 32 33 /* Just increment the non-pointer handle value */ 34 static handle_t *ext4_get_nojournal(void) 35 { 36 handle_t *handle = current->journal_info; 37 unsigned long ref_cnt = (unsigned long)handle; 38 39 BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT); 40 41 ref_cnt++; 42 handle = (handle_t *)ref_cnt; 43 44 current->journal_info = handle; 45 return handle; 46 } 47 48 49 /* Decrement the non-pointer handle value */ 50 static void ext4_put_nojournal(handle_t *handle) 51 { 52 unsigned long ref_cnt = (unsigned long)handle; 53 54 BUG_ON(ref_cnt == 0); 55 56 ref_cnt--; 57 handle = (handle_t *)ref_cnt; 58 59 current->journal_info = handle; 60 } 61 62 /* 63 * Wrappers for jbd2_journal_start/end. 64 */ 65 static int ext4_journal_check_start(struct super_block *sb) 66 { 67 int ret; 68 journal_t *journal; 69 70 might_sleep(); 71 72 ret = ext4_emergency_state(sb); 73 if (unlikely(ret)) 74 return ret; 75 76 if (WARN_ON_ONCE(sb_rdonly(sb))) 77 return -EROFS; 78 79 WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE); 80 journal = EXT4_SB(sb)->s_journal; 81 /* 82 * Special case here: if the journal has aborted behind our 83 * backs (eg. EIO in the commit thread), then we still need to 84 * take the FS itself readonly cleanly. 85 */ 86 if (journal && is_journal_aborted(journal)) { 87 ext4_abort(sb, -journal->j_errno, "Detected aborted journal"); 88 return -EROFS; 89 } 90 return 0; 91 } 92 93 handle_t *__ext4_journal_start_sb(struct inode *inode, 94 struct super_block *sb, unsigned int line, 95 int type, int blocks, int rsv_blocks, 96 int revoke_creds) 97 { 98 journal_t *journal; 99 int err; 100 if (inode) 101 trace_ext4_journal_start_inode(inode, blocks, rsv_blocks, 102 revoke_creds, type, 103 _RET_IP_); 104 else 105 trace_ext4_journal_start_sb(sb, blocks, rsv_blocks, 106 revoke_creds, type, 107 _RET_IP_); 108 err = ext4_journal_check_start(sb); 109 if (err < 0) 110 return ERR_PTR(err); 111 112 journal = EXT4_SB(sb)->s_journal; 113 if (!journal || (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY)) 114 return ext4_get_nojournal(); 115 return jbd2__journal_start(journal, blocks, rsv_blocks, revoke_creds, 116 GFP_NOFS, type, line); 117 } 118 119 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle) 120 { 121 struct super_block *sb; 122 int err; 123 int rc; 124 125 if (!ext4_handle_valid(handle)) { 126 ext4_put_nojournal(handle); 127 return 0; 128 } 129 130 err = handle->h_err; 131 if (!handle->h_transaction) { 132 rc = jbd2_journal_stop(handle); 133 return err ? err : rc; 134 } 135 136 sb = handle->h_transaction->t_journal->j_private; 137 rc = jbd2_journal_stop(handle); 138 139 if (!err) 140 err = rc; 141 if (err) 142 __ext4_std_error(sb, where, line, err); 143 return err; 144 } 145 146 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, 147 int type) 148 { 149 struct super_block *sb; 150 int err; 151 152 if (!ext4_handle_valid(handle)) 153 return ext4_get_nojournal(); 154 155 sb = handle->h_journal->j_private; 156 trace_ext4_journal_start_reserved(sb, 157 jbd2_handle_buffer_credits(handle), _RET_IP_); 158 err = ext4_journal_check_start(sb); 159 if (err < 0) { 160 jbd2_journal_free_reserved(handle); 161 return ERR_PTR(err); 162 } 163 164 err = jbd2_journal_start_reserved(handle, type, line); 165 if (err < 0) 166 return ERR_PTR(err); 167 return handle; 168 } 169 170 int __ext4_journal_ensure_credits(handle_t *handle, int check_cred, 171 int extend_cred, int revoke_cred) 172 { 173 if (!ext4_handle_valid(handle)) 174 return 0; 175 if (is_handle_aborted(handle)) 176 return -EROFS; 177 if (jbd2_handle_buffer_credits(handle) >= check_cred && 178 handle->h_revoke_credits >= revoke_cred) 179 return 0; 180 extend_cred = max(0, extend_cred - jbd2_handle_buffer_credits(handle)); 181 revoke_cred = max(0, revoke_cred - handle->h_revoke_credits); 182 return ext4_journal_extend(handle, extend_cred, revoke_cred); 183 } 184 185 static void ext4_journal_abort_handle(const char *caller, unsigned int line, 186 const char *err_fn, 187 struct buffer_head *bh, 188 handle_t *handle, int err) 189 { 190 char nbuf[16]; 191 const char *errstr = ext4_decode_error(NULL, err, nbuf); 192 193 BUG_ON(!ext4_handle_valid(handle)); 194 195 if (bh) 196 BUFFER_TRACE(bh, "abort"); 197 198 if (!handle->h_err) 199 handle->h_err = err; 200 201 if (is_handle_aborted(handle)) 202 return; 203 204 printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n", 205 caller, line, errstr, err_fn); 206 207 jbd2_journal_abort_handle(handle); 208 } 209 210 static void ext4_check_bdev_write_error(struct super_block *sb) 211 { 212 struct address_space *mapping = sb->s_bdev->bd_mapping; 213 struct ext4_sb_info *sbi = EXT4_SB(sb); 214 int err; 215 216 /* 217 * If the block device has write error flag, it may have failed to 218 * async write out metadata buffers in the background. In this case, 219 * we could read old data from disk and write it out again, which 220 * may lead to on-disk filesystem inconsistency. 221 */ 222 if (errseq_check(&mapping->wb_err, READ_ONCE(sbi->s_bdev_wb_err))) { 223 spin_lock(&sbi->s_bdev_wb_lock); 224 err = errseq_check_and_advance(&mapping->wb_err, &sbi->s_bdev_wb_err); 225 spin_unlock(&sbi->s_bdev_wb_lock); 226 if (err) 227 ext4_error_err(sb, -err, 228 "Error while async write back metadata"); 229 } 230 } 231 232 int __ext4_journal_get_write_access(const char *where, unsigned int line, 233 handle_t *handle, struct super_block *sb, 234 struct buffer_head *bh, 235 enum ext4_journal_trigger_type trigger_type) 236 { 237 int err; 238 239 might_sleep(); 240 241 if (ext4_handle_valid(handle)) { 242 err = jbd2_journal_get_write_access(handle, bh); 243 if (err) { 244 ext4_journal_abort_handle(where, line, __func__, bh, 245 handle, err); 246 return err; 247 } 248 } else 249 ext4_check_bdev_write_error(sb); 250 if (trigger_type == EXT4_JTR_NONE || 251 !ext4_has_feature_metadata_csum(sb)) 252 return 0; 253 BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT); 254 jbd2_journal_set_triggers(bh, 255 &EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers); 256 return 0; 257 } 258 259 /* 260 * The ext4 forget function must perform a revoke if we are freeing data 261 * which has been journaled. Metadata (eg. indirect blocks) must be 262 * revoked in all cases. 263 * 264 * "bh" may be NULL: a metadata block may have been freed from memory 265 * but there may still be a record of it in the journal, and that record 266 * still needs to be revoked. 267 */ 268 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 269 int is_metadata, struct inode *inode, 270 struct buffer_head *bh, ext4_fsblk_t blocknr) 271 { 272 int err; 273 274 might_sleep(); 275 276 trace_ext4_forget(inode, is_metadata, blocknr); 277 BUFFER_TRACE(bh, "enter"); 278 279 ext4_debug("forgetting bh %p: is_metadata=%d, mode %o, data mode %x\n", 280 bh, is_metadata, inode->i_mode, 281 test_opt(inode->i_sb, DATA_FLAGS)); 282 283 /* In the no journal case, we can just do a bforget and return */ 284 if (!ext4_handle_valid(handle)) { 285 bforget(bh); 286 return 0; 287 } 288 289 /* Never use the revoke function if we are doing full data 290 * journaling: there is no need to, and a V1 superblock won't 291 * support it. Otherwise, only skip the revoke on un-journaled 292 * data blocks. */ 293 294 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || 295 (!is_metadata && !ext4_should_journal_data(inode))) { 296 if (bh) { 297 BUFFER_TRACE(bh, "call jbd2_journal_forget"); 298 err = jbd2_journal_forget(handle, bh); 299 if (err) 300 ext4_journal_abort_handle(where, line, __func__, 301 bh, handle, err); 302 return err; 303 } 304 return 0; 305 } 306 307 /* 308 * data!=journal && (is_metadata || should_journal_data(inode)) 309 */ 310 BUFFER_TRACE(bh, "call jbd2_journal_revoke"); 311 err = jbd2_journal_revoke(handle, blocknr, bh); 312 if (err) { 313 ext4_journal_abort_handle(where, line, __func__, 314 bh, handle, err); 315 __ext4_error(inode->i_sb, where, line, true, -err, 0, 316 "error %d when attempting revoke", err); 317 } 318 BUFFER_TRACE(bh, "exit"); 319 return err; 320 } 321 322 int __ext4_journal_get_create_access(const char *where, unsigned int line, 323 handle_t *handle, struct super_block *sb, 324 struct buffer_head *bh, 325 enum ext4_journal_trigger_type trigger_type) 326 { 327 int err; 328 329 if (!ext4_handle_valid(handle)) 330 return 0; 331 332 err = jbd2_journal_get_create_access(handle, bh); 333 if (err) { 334 ext4_journal_abort_handle(where, line, __func__, bh, handle, 335 err); 336 return err; 337 } 338 if (trigger_type == EXT4_JTR_NONE || 339 !ext4_has_feature_metadata_csum(sb)) 340 return 0; 341 BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT); 342 jbd2_journal_set_triggers(bh, 343 &EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers); 344 return 0; 345 } 346 347 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 348 handle_t *handle, struct inode *inode, 349 struct buffer_head *bh) 350 { 351 int err = 0; 352 353 might_sleep(); 354 355 set_buffer_meta(bh); 356 set_buffer_prio(bh); 357 set_buffer_uptodate(bh); 358 if (ext4_handle_valid(handle)) { 359 err = jbd2_journal_dirty_metadata(handle, bh); 360 /* Errors can only happen due to aborted journal or a nasty bug */ 361 if (!is_handle_aborted(handle) && WARN_ON_ONCE(err)) { 362 ext4_journal_abort_handle(where, line, __func__, bh, 363 handle, err); 364 if (inode == NULL) { 365 pr_err("EXT4: jbd2_journal_dirty_metadata " 366 "failed: handle type %u started at " 367 "line %u, credits %u/%u, errcode %d", 368 handle->h_type, 369 handle->h_line_no, 370 handle->h_requested_credits, 371 jbd2_handle_buffer_credits(handle), err); 372 return err; 373 } 374 ext4_error_inode(inode, where, line, 375 bh->b_blocknr, 376 "journal_dirty_metadata failed: " 377 "handle type %u started at line %u, " 378 "credits %u/%u, errcode %d", 379 handle->h_type, 380 handle->h_line_no, 381 handle->h_requested_credits, 382 jbd2_handle_buffer_credits(handle), 383 err); 384 } 385 } else { 386 if (inode) 387 mark_buffer_dirty_inode(bh, inode); 388 else 389 mark_buffer_dirty(bh); 390 if (inode && inode_needs_sync(inode)) { 391 sync_dirty_buffer(bh); 392 if (buffer_req(bh) && !buffer_uptodate(bh)) { 393 ext4_error_inode_err(inode, where, line, 394 bh->b_blocknr, EIO, 395 "IO error syncing itable block"); 396 err = -EIO; 397 } 398 } 399 } 400 return err; 401 } 402