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(EXT4_SB(sb)))) 71 return -EIO; 72 73 if (sb_rdonly(sb)) 74 return -EROFS; 75 WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE); 76 journal = EXT4_SB(sb)->s_journal; 77 /* 78 * Special case here: if the journal has aborted behind our 79 * backs (eg. EIO in the commit thread), then we still need to 80 * take the FS itself readonly cleanly. 81 */ 82 if (journal && is_journal_aborted(journal)) { 83 ext4_abort(sb, -journal->j_errno, "Detected aborted journal"); 84 return -EROFS; 85 } 86 return 0; 87 } 88 89 handle_t *__ext4_journal_start_sb(struct inode *inode, 90 struct super_block *sb, unsigned int line, 91 int type, int blocks, int rsv_blocks, 92 int revoke_creds) 93 { 94 journal_t *journal; 95 int err; 96 if (inode) 97 trace_ext4_journal_start_inode(inode, blocks, rsv_blocks, 98 revoke_creds, type, 99 _RET_IP_); 100 else 101 trace_ext4_journal_start_sb(sb, blocks, rsv_blocks, 102 revoke_creds, type, 103 _RET_IP_); 104 err = ext4_journal_check_start(sb); 105 if (err < 0) 106 return ERR_PTR(err); 107 108 journal = EXT4_SB(sb)->s_journal; 109 if (!journal || (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY)) 110 return ext4_get_nojournal(); 111 return jbd2__journal_start(journal, blocks, rsv_blocks, revoke_creds, 112 GFP_NOFS, type, line); 113 } 114 115 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle) 116 { 117 struct super_block *sb; 118 int err; 119 int rc; 120 121 if (!ext4_handle_valid(handle)) { 122 ext4_put_nojournal(handle); 123 return 0; 124 } 125 126 err = handle->h_err; 127 if (!handle->h_transaction) { 128 rc = jbd2_journal_stop(handle); 129 return err ? err : rc; 130 } 131 132 sb = handle->h_transaction->t_journal->j_private; 133 rc = jbd2_journal_stop(handle); 134 135 if (!err) 136 err = rc; 137 if (err) 138 __ext4_std_error(sb, where, line, err); 139 return err; 140 } 141 142 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, 143 int type) 144 { 145 struct super_block *sb; 146 int err; 147 148 if (!ext4_handle_valid(handle)) 149 return ext4_get_nojournal(); 150 151 sb = handle->h_journal->j_private; 152 trace_ext4_journal_start_reserved(sb, 153 jbd2_handle_buffer_credits(handle), _RET_IP_); 154 err = ext4_journal_check_start(sb); 155 if (err < 0) { 156 jbd2_journal_free_reserved(handle); 157 return ERR_PTR(err); 158 } 159 160 err = jbd2_journal_start_reserved(handle, type, line); 161 if (err < 0) 162 return ERR_PTR(err); 163 return handle; 164 } 165 166 int __ext4_journal_ensure_credits(handle_t *handle, int check_cred, 167 int extend_cred, int revoke_cred) 168 { 169 if (!ext4_handle_valid(handle)) 170 return 0; 171 if (is_handle_aborted(handle)) 172 return -EROFS; 173 if (jbd2_handle_buffer_credits(handle) >= check_cred && 174 handle->h_revoke_credits >= revoke_cred) 175 return 0; 176 extend_cred = max(0, extend_cred - jbd2_handle_buffer_credits(handle)); 177 revoke_cred = max(0, revoke_cred - handle->h_revoke_credits); 178 return ext4_journal_extend(handle, extend_cred, revoke_cred); 179 } 180 181 static void ext4_journal_abort_handle(const char *caller, unsigned int line, 182 const char *err_fn, 183 struct buffer_head *bh, 184 handle_t *handle, int err) 185 { 186 char nbuf[16]; 187 const char *errstr = ext4_decode_error(NULL, err, nbuf); 188 189 BUG_ON(!ext4_handle_valid(handle)); 190 191 if (bh) 192 BUFFER_TRACE(bh, "abort"); 193 194 if (!handle->h_err) 195 handle->h_err = err; 196 197 if (is_handle_aborted(handle)) 198 return; 199 200 printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n", 201 caller, line, errstr, err_fn); 202 203 jbd2_journal_abort_handle(handle); 204 } 205 206 static void ext4_check_bdev_write_error(struct super_block *sb) 207 { 208 struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping; 209 struct ext4_sb_info *sbi = EXT4_SB(sb); 210 int err; 211 212 /* 213 * If the block device has write error flag, it may have failed to 214 * async write out metadata buffers in the background. In this case, 215 * we could read old data from disk and write it out again, which 216 * may lead to on-disk filesystem inconsistency. 217 */ 218 if (errseq_check(&mapping->wb_err, READ_ONCE(sbi->s_bdev_wb_err))) { 219 spin_lock(&sbi->s_bdev_wb_lock); 220 err = errseq_check_and_advance(&mapping->wb_err, &sbi->s_bdev_wb_err); 221 spin_unlock(&sbi->s_bdev_wb_lock); 222 if (err) 223 ext4_error_err(sb, -err, 224 "Error while async write back metadata"); 225 } 226 } 227 228 int __ext4_journal_get_write_access(const char *where, unsigned int line, 229 handle_t *handle, struct super_block *sb, 230 struct buffer_head *bh, 231 enum ext4_journal_trigger_type trigger_type) 232 { 233 int err; 234 235 might_sleep(); 236 237 if (bh->b_bdev->bd_super) 238 ext4_check_bdev_write_error(bh->b_bdev->bd_super); 239 240 if (ext4_handle_valid(handle)) { 241 err = jbd2_journal_get_write_access(handle, bh); 242 if (err) { 243 ext4_journal_abort_handle(where, line, __func__, bh, 244 handle, err); 245 return err; 246 } 247 } 248 if (trigger_type == EXT4_JTR_NONE || !ext4_has_metadata_csum(sb)) 249 return 0; 250 BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT); 251 jbd2_journal_set_triggers(bh, 252 &EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers); 253 return 0; 254 } 255 256 /* 257 * The ext4 forget function must perform a revoke if we are freeing data 258 * which has been journaled. Metadata (eg. indirect blocks) must be 259 * revoked in all cases. 260 * 261 * "bh" may be NULL: a metadata block may have been freed from memory 262 * but there may still be a record of it in the journal, and that record 263 * still needs to be revoked. 264 */ 265 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 266 int is_metadata, struct inode *inode, 267 struct buffer_head *bh, ext4_fsblk_t blocknr) 268 { 269 int err; 270 271 might_sleep(); 272 273 trace_ext4_forget(inode, is_metadata, blocknr); 274 BUFFER_TRACE(bh, "enter"); 275 276 ext4_debug("forgetting bh %p: is_metadata=%d, mode %o, data mode %x\n", 277 bh, is_metadata, inode->i_mode, 278 test_opt(inode->i_sb, DATA_FLAGS)); 279 280 /* In the no journal case, we can just do a bforget and return */ 281 if (!ext4_handle_valid(handle)) { 282 bforget(bh); 283 return 0; 284 } 285 286 /* Never use the revoke function if we are doing full data 287 * journaling: there is no need to, and a V1 superblock won't 288 * support it. Otherwise, only skip the revoke on un-journaled 289 * data blocks. */ 290 291 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || 292 (!is_metadata && !ext4_should_journal_data(inode))) { 293 if (bh) { 294 BUFFER_TRACE(bh, "call jbd2_journal_forget"); 295 err = jbd2_journal_forget(handle, bh); 296 if (err) 297 ext4_journal_abort_handle(where, line, __func__, 298 bh, handle, err); 299 return err; 300 } 301 return 0; 302 } 303 304 /* 305 * data!=journal && (is_metadata || should_journal_data(inode)) 306 */ 307 BUFFER_TRACE(bh, "call jbd2_journal_revoke"); 308 err = jbd2_journal_revoke(handle, blocknr, bh); 309 if (err) { 310 ext4_journal_abort_handle(where, line, __func__, 311 bh, handle, err); 312 __ext4_error(inode->i_sb, where, line, true, -err, 0, 313 "error %d when attempting revoke", err); 314 } 315 BUFFER_TRACE(bh, "exit"); 316 return err; 317 } 318 319 int __ext4_journal_get_create_access(const char *where, unsigned int line, 320 handle_t *handle, struct super_block *sb, 321 struct buffer_head *bh, 322 enum ext4_journal_trigger_type trigger_type) 323 { 324 int err; 325 326 if (!ext4_handle_valid(handle)) 327 return 0; 328 329 err = jbd2_journal_get_create_access(handle, bh); 330 if (err) { 331 ext4_journal_abort_handle(where, line, __func__, bh, handle, 332 err); 333 return err; 334 } 335 if (trigger_type == EXT4_JTR_NONE || !ext4_has_metadata_csum(sb)) 336 return 0; 337 BUG_ON(trigger_type >= EXT4_JOURNAL_TRIGGER_COUNT); 338 jbd2_journal_set_triggers(bh, 339 &EXT4_SB(sb)->s_journal_triggers[trigger_type].tr_triggers); 340 return 0; 341 } 342 343 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 344 handle_t *handle, struct inode *inode, 345 struct buffer_head *bh) 346 { 347 int err = 0; 348 349 might_sleep(); 350 351 set_buffer_meta(bh); 352 set_buffer_prio(bh); 353 set_buffer_uptodate(bh); 354 if (ext4_handle_valid(handle)) { 355 err = jbd2_journal_dirty_metadata(handle, bh); 356 /* Errors can only happen due to aborted journal or a nasty bug */ 357 if (!is_handle_aborted(handle) && WARN_ON_ONCE(err)) { 358 ext4_journal_abort_handle(where, line, __func__, bh, 359 handle, err); 360 if (inode == NULL) { 361 pr_err("EXT4: jbd2_journal_dirty_metadata " 362 "failed: handle type %u started at " 363 "line %u, credits %u/%u, errcode %d", 364 handle->h_type, 365 handle->h_line_no, 366 handle->h_requested_credits, 367 jbd2_handle_buffer_credits(handle), err); 368 return err; 369 } 370 ext4_error_inode(inode, where, line, 371 bh->b_blocknr, 372 "journal_dirty_metadata failed: " 373 "handle type %u started at line %u, " 374 "credits %u/%u, errcode %d", 375 handle->h_type, 376 handle->h_line_no, 377 handle->h_requested_credits, 378 jbd2_handle_buffer_credits(handle), 379 err); 380 } 381 } else { 382 if (inode) 383 mark_buffer_dirty_inode(bh, inode); 384 else 385 mark_buffer_dirty(bh); 386 if (inode && inode_needs_sync(inode)) { 387 sync_dirty_buffer(bh); 388 if (buffer_req(bh) && !buffer_uptodate(bh)) { 389 ext4_error_inode_err(inode, where, line, 390 bh->b_blocknr, EIO, 391 "IO error syncing itable block"); 392 err = -EIO; 393 } 394 } 395 } 396 return err; 397 } 398