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 /* We do not support data journalling for encrypted data */ 21 if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode)) 22 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 23 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 24 } 25 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 26 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 27 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 28 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 29 BUG(); 30 } 31 32 /* Just increment the non-pointer handle value */ 33 static handle_t *ext4_get_nojournal(void) 34 { 35 handle_t *handle = current->journal_info; 36 unsigned long ref_cnt = (unsigned long)handle; 37 38 BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT); 39 40 ref_cnt++; 41 handle = (handle_t *)ref_cnt; 42 43 current->journal_info = handle; 44 return handle; 45 } 46 47 48 /* Decrement the non-pointer handle value */ 49 static void ext4_put_nojournal(handle_t *handle) 50 { 51 unsigned long ref_cnt = (unsigned long)handle; 52 53 BUG_ON(ref_cnt == 0); 54 55 ref_cnt--; 56 handle = (handle_t *)ref_cnt; 57 58 current->journal_info = handle; 59 } 60 61 /* 62 * Wrappers for jbd2_journal_start/end. 63 */ 64 static int ext4_journal_check_start(struct super_block *sb) 65 { 66 journal_t *journal; 67 68 might_sleep(); 69 70 if (unlikely(ext4_forced_shutdown(sb))) 71 return -EIO; 72 73 if (WARN_ON_ONCE(sb_rdonly(sb))) 74 return -EROFS; 75 76 WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE); 77 journal = EXT4_SB(sb)->s_journal; 78 /* 79 * Special case here: if the journal has aborted behind our 80 * backs (eg. EIO in the commit thread), then we still need to 81 * take the FS itself readonly cleanly. 82 */ 83 if (journal && is_journal_aborted(journal)) { 84 ext4_abort(sb, -journal->j_errno, "Detected aborted journal"); 85 return -EROFS; 86 } 87 return 0; 88 } 89 90 handle_t *__ext4_journal_start_sb(struct inode *inode, 91 struct super_block *sb, unsigned int line, 92 int type, int blocks, int rsv_blocks, 93 int revoke_creds) 94 { 95 journal_t *journal; 96 int err; 97 if (inode) 98 trace_ext4_journal_start_inode(inode, blocks, rsv_blocks, 99 revoke_creds, type, 100 _RET_IP_); 101 else 102 trace_ext4_journal_start_sb(sb, blocks, rsv_blocks, 103 revoke_creds, type, 104 _RET_IP_); 105 err = ext4_journal_check_start(sb); 106 if (err < 0) 107 return ERR_PTR(err); 108 109 journal = EXT4_SB(sb)->s_journal; 110 if (!journal || (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY)) 111 return ext4_get_nojournal(); 112 return jbd2__journal_start(journal, blocks, rsv_blocks, revoke_creds, 113 GFP_NOFS, type, line); 114 } 115 116 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle) 117 { 118 struct super_block *sb; 119 int err; 120 int rc; 121 122 if (!ext4_handle_valid(handle)) { 123 ext4_put_nojournal(handle); 124 return 0; 125 } 126 127 err = handle->h_err; 128 if (!handle->h_transaction) { 129 rc = jbd2_journal_stop(handle); 130 return err ? err : rc; 131 } 132 133 sb = handle->h_transaction->t_journal->j_private; 134 rc = jbd2_journal_stop(handle); 135 136 if (!err) 137 err = rc; 138 if (err) 139 __ext4_std_error(sb, where, line, err); 140 return err; 141 } 142 143 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, 144 int type) 145 { 146 struct super_block *sb; 147 int err; 148 149 if (!ext4_handle_valid(handle)) 150 return ext4_get_nojournal(); 151 152 sb = handle->h_journal->j_private; 153 trace_ext4_journal_start_reserved(sb, 154 jbd2_handle_buffer_credits(handle), _RET_IP_); 155 err = ext4_journal_check_start(sb); 156 if (err < 0) { 157 jbd2_journal_free_reserved(handle); 158 return ERR_PTR(err); 159 } 160 161 err = jbd2_journal_start_reserved(handle, type, line); 162 if (err < 0) 163 return ERR_PTR(err); 164 return handle; 165 } 166 167 int __ext4_journal_ensure_credits(handle_t *handle, int check_cred, 168 int extend_cred, int revoke_cred) 169 { 170 if (!ext4_handle_valid(handle)) 171 return 0; 172 if (is_handle_aborted(handle)) 173 return -EROFS; 174 if (jbd2_handle_buffer_credits(handle) >= check_cred && 175 handle->h_revoke_credits >= revoke_cred) 176 return 0; 177 extend_cred = max(0, extend_cred - jbd2_handle_buffer_credits(handle)); 178 revoke_cred = max(0, revoke_cred - handle->h_revoke_credits); 179 return ext4_journal_extend(handle, extend_cred, revoke_cred); 180 } 181 182 static void ext4_journal_abort_handle(const char *caller, unsigned int line, 183 const char *err_fn, 184 struct buffer_head *bh, 185 handle_t *handle, int err) 186 { 187 char nbuf[16]; 188 const char *errstr = ext4_decode_error(NULL, err, nbuf); 189 190 BUG_ON(!ext4_handle_valid(handle)); 191 192 if (bh) 193 BUFFER_TRACE(bh, "abort"); 194 195 if (!handle->h_err) 196 handle->h_err = err; 197 198 if (is_handle_aborted(handle)) 199 return; 200 201 printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n", 202 caller, line, errstr, err_fn); 203 204 jbd2_journal_abort_handle(handle); 205 } 206 207 static void ext4_check_bdev_write_error(struct super_block *sb) 208 { 209 struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping; 210 struct ext4_sb_info *sbi = EXT4_SB(sb); 211 int err; 212 213 /* 214 * If the block device has write error flag, it may have failed to 215 * async write out metadata buffers in the background. In this case, 216 * we could read old data from disk and write it out again, which 217 * may lead to on-disk filesystem inconsistency. 218 */ 219 if (errseq_check(&mapping->wb_err, READ_ONCE(sbi->s_bdev_wb_err))) { 220 spin_lock(&sbi->s_bdev_wb_lock); 221 err = errseq_check_and_advance(&mapping->wb_err, &sbi->s_bdev_wb_err); 222 spin_unlock(&sbi->s_bdev_wb_lock); 223 if (err) 224 ext4_error_err(sb, -err, 225 "Error while async write back metadata"); 226 } 227 } 228 229 int __ext4_journal_get_write_access(const char *where, unsigned int line, 230 handle_t *handle, struct super_block *sb, 231 struct buffer_head *bh, 232 enum ext4_journal_trigger_type trigger_type) 233 { 234 int err; 235 236 might_sleep(); 237 238 if (ext4_handle_valid(handle)) { 239 err = jbd2_journal_get_write_access(handle, bh); 240 if (err) { 241 ext4_journal_abort_handle(where, line, __func__, bh, 242 handle, err); 243 return err; 244 } 245 } else 246 ext4_check_bdev_write_error(sb); 247 if (trigger_type == EXT4_JTR_NONE || !ext4_has_metadata_csum(sb)) 248 return 0; 249 BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT); 250 jbd2_journal_set_triggers(bh, 251 &EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers); 252 return 0; 253 } 254 255 /* 256 * The ext4 forget function must perform a revoke if we are freeing data 257 * which has been journaled. Metadata (eg. indirect blocks) must be 258 * revoked in all cases. 259 * 260 * "bh" may be NULL: a metadata block may have been freed from memory 261 * but there may still be a record of it in the journal, and that record 262 * still needs to be revoked. 263 */ 264 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 265 int is_metadata, struct inode *inode, 266 struct buffer_head *bh, ext4_fsblk_t blocknr) 267 { 268 int err; 269 270 might_sleep(); 271 272 trace_ext4_forget(inode, is_metadata, blocknr); 273 BUFFER_TRACE(bh, "enter"); 274 275 ext4_debug("forgetting bh %p: is_metadata=%d, mode %o, data mode %x\n", 276 bh, is_metadata, inode->i_mode, 277 test_opt(inode->i_sb, DATA_FLAGS)); 278 279 /* In the no journal case, we can just do a bforget and return */ 280 if (!ext4_handle_valid(handle)) { 281 bforget(bh); 282 return 0; 283 } 284 285 /* Never use the revoke function if we are doing full data 286 * journaling: there is no need to, and a V1 superblock won't 287 * support it. Otherwise, only skip the revoke on un-journaled 288 * data blocks. */ 289 290 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || 291 (!is_metadata && !ext4_should_journal_data(inode))) { 292 if (bh) { 293 BUFFER_TRACE(bh, "call jbd2_journal_forget"); 294 err = jbd2_journal_forget(handle, bh); 295 if (err) 296 ext4_journal_abort_handle(where, line, __func__, 297 bh, handle, err); 298 return err; 299 } 300 return 0; 301 } 302 303 /* 304 * data!=journal && (is_metadata || should_journal_data(inode)) 305 */ 306 BUFFER_TRACE(bh, "call jbd2_journal_revoke"); 307 err = jbd2_journal_revoke(handle, blocknr, bh); 308 if (err) { 309 ext4_journal_abort_handle(where, line, __func__, 310 bh, handle, err); 311 __ext4_error(inode->i_sb, where, line, true, -err, 0, 312 "error %d when attempting revoke", err); 313 } 314 BUFFER_TRACE(bh, "exit"); 315 return err; 316 } 317 318 int __ext4_journal_get_create_access(const char *where, unsigned int line, 319 handle_t *handle, struct super_block *sb, 320 struct buffer_head *bh, 321 enum ext4_journal_trigger_type trigger_type) 322 { 323 int err; 324 325 if (!ext4_handle_valid(handle)) 326 return 0; 327 328 err = jbd2_journal_get_create_access(handle, bh); 329 if (err) { 330 ext4_journal_abort_handle(where, line, __func__, bh, handle, 331 err); 332 return err; 333 } 334 if (trigger_type == EXT4_JTR_NONE || !ext4_has_metadata_csum(sb)) 335 return 0; 336 BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT); 337 jbd2_journal_set_triggers(bh, 338 &EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers); 339 return 0; 340 } 341 342 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 343 handle_t *handle, struct inode *inode, 344 struct buffer_head *bh) 345 { 346 int err = 0; 347 348 might_sleep(); 349 350 set_buffer_meta(bh); 351 set_buffer_prio(bh); 352 set_buffer_uptodate(bh); 353 if (ext4_handle_valid(handle)) { 354 err = jbd2_journal_dirty_metadata(handle, bh); 355 /* Errors can only happen due to aborted journal or a nasty bug */ 356 if (!is_handle_aborted(handle) && WARN_ON_ONCE(err)) { 357 ext4_journal_abort_handle(where, line, __func__, bh, 358 handle, err); 359 if (inode == NULL) { 360 pr_err("EXT4: jbd2_journal_dirty_metadata " 361 "failed: handle type %u started at " 362 "line %u, credits %u/%u, errcode %d", 363 handle->h_type, 364 handle->h_line_no, 365 handle->h_requested_credits, 366 jbd2_handle_buffer_credits(handle), err); 367 return err; 368 } 369 ext4_error_inode(inode, where, line, 370 bh->b_blocknr, 371 "journal_dirty_metadata failed: " 372 "handle type %u started at line %u, " 373 "credits %u/%u, errcode %d", 374 handle->h_type, 375 handle->h_line_no, 376 handle->h_requested_credits, 377 jbd2_handle_buffer_credits(handle), 378 err); 379 } 380 } else { 381 if (inode) 382 mark_buffer_dirty_inode(bh, inode); 383 else 384 mark_buffer_dirty(bh); 385 if (inode && inode_needs_sync(inode)) { 386 sync_dirty_buffer(bh); 387 if (buffer_req(bh) && !buffer_uptodate(bh)) { 388 ext4_error_inode_err(inode, where, line, 389 bh->b_blocknr, EIO, 390 "IO error syncing itable block"); 391 err = -EIO; 392 } 393 } 394 } 395 return err; 396 } 397