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_set_errno(sb, -journal->j_errno); 84 ext4_abort(sb, "Detected aborted journal"); 85 return -EROFS; 86 } 87 return 0; 88 } 89 90 handle_t *__ext4_journal_start_sb(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 97 trace_ext4_journal_start(sb, blocks, rsv_blocks, revoke_creds, 98 _RET_IP_); 99 err = ext4_journal_check_start(sb); 100 if (err < 0) 101 return ERR_PTR(err); 102 103 journal = EXT4_SB(sb)->s_journal; 104 if (!journal) 105 return ext4_get_nojournal(); 106 return jbd2__journal_start(journal, blocks, rsv_blocks, revoke_creds, 107 GFP_NOFS, type, line); 108 } 109 110 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle) 111 { 112 struct super_block *sb; 113 int err; 114 int rc; 115 116 if (!ext4_handle_valid(handle)) { 117 ext4_put_nojournal(handle); 118 return 0; 119 } 120 121 err = handle->h_err; 122 if (!handle->h_transaction) { 123 rc = jbd2_journal_stop(handle); 124 return err ? err : rc; 125 } 126 127 sb = handle->h_transaction->t_journal->j_private; 128 rc = jbd2_journal_stop(handle); 129 130 if (!err) 131 err = rc; 132 if (err) 133 __ext4_std_error(sb, where, line, err); 134 return err; 135 } 136 137 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, 138 int type) 139 { 140 struct super_block *sb; 141 int err; 142 143 if (!ext4_handle_valid(handle)) 144 return ext4_get_nojournal(); 145 146 sb = handle->h_journal->j_private; 147 trace_ext4_journal_start_reserved(sb, 148 jbd2_handle_buffer_credits(handle), _RET_IP_); 149 err = ext4_journal_check_start(sb); 150 if (err < 0) { 151 jbd2_journal_free_reserved(handle); 152 return ERR_PTR(err); 153 } 154 155 err = jbd2_journal_start_reserved(handle, type, line); 156 if (err < 0) 157 return ERR_PTR(err); 158 return handle; 159 } 160 161 int __ext4_journal_ensure_credits(handle_t *handle, int check_cred, 162 int extend_cred, int revoke_cred) 163 { 164 if (!ext4_handle_valid(handle)) 165 return 0; 166 if (jbd2_handle_buffer_credits(handle) >= check_cred && 167 handle->h_revoke_credits >= revoke_cred) 168 return 0; 169 extend_cred = max(0, extend_cred - jbd2_handle_buffer_credits(handle)); 170 revoke_cred = max(0, revoke_cred - handle->h_revoke_credits); 171 return ext4_journal_extend(handle, extend_cred, revoke_cred); 172 } 173 174 static void ext4_journal_abort_handle(const char *caller, unsigned int line, 175 const char *err_fn, 176 struct buffer_head *bh, 177 handle_t *handle, int err) 178 { 179 char nbuf[16]; 180 const char *errstr = ext4_decode_error(NULL, err, nbuf); 181 182 BUG_ON(!ext4_handle_valid(handle)); 183 184 if (bh) 185 BUFFER_TRACE(bh, "abort"); 186 187 if (!handle->h_err) 188 handle->h_err = err; 189 190 if (is_handle_aborted(handle)) 191 return; 192 193 printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n", 194 caller, line, errstr, err_fn); 195 196 jbd2_journal_abort_handle(handle); 197 } 198 199 int __ext4_journal_get_write_access(const char *where, unsigned int line, 200 handle_t *handle, struct buffer_head *bh) 201 { 202 int err = 0; 203 204 might_sleep(); 205 206 if (ext4_handle_valid(handle)) { 207 err = jbd2_journal_get_write_access(handle, bh); 208 if (err) 209 ext4_journal_abort_handle(where, line, __func__, bh, 210 handle, err); 211 } 212 return err; 213 } 214 215 /* 216 * The ext4 forget function must perform a revoke if we are freeing data 217 * which has been journaled. Metadata (eg. indirect blocks) must be 218 * revoked in all cases. 219 * 220 * "bh" may be NULL: a metadata block may have been freed from memory 221 * but there may still be a record of it in the journal, and that record 222 * still needs to be revoked. 223 * 224 * If the handle isn't valid we're not journaling, but we still need to 225 * call into ext4_journal_revoke() to put the buffer head. 226 */ 227 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 228 int is_metadata, struct inode *inode, 229 struct buffer_head *bh, ext4_fsblk_t blocknr) 230 { 231 int err; 232 233 might_sleep(); 234 235 trace_ext4_forget(inode, is_metadata, blocknr); 236 BUFFER_TRACE(bh, "enter"); 237 238 jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " 239 "data mode %x\n", 240 bh, is_metadata, inode->i_mode, 241 test_opt(inode->i_sb, DATA_FLAGS)); 242 243 /* In the no journal case, we can just do a bforget and return */ 244 if (!ext4_handle_valid(handle)) { 245 bforget(bh); 246 return 0; 247 } 248 249 /* Never use the revoke function if we are doing full data 250 * journaling: there is no need to, and a V1 superblock won't 251 * support it. Otherwise, only skip the revoke on un-journaled 252 * data blocks. */ 253 254 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || 255 (!is_metadata && !ext4_should_journal_data(inode))) { 256 if (bh) { 257 BUFFER_TRACE(bh, "call jbd2_journal_forget"); 258 err = jbd2_journal_forget(handle, bh); 259 if (err) 260 ext4_journal_abort_handle(where, line, __func__, 261 bh, handle, err); 262 return err; 263 } 264 return 0; 265 } 266 267 /* 268 * data!=journal && (is_metadata || should_journal_data(inode)) 269 */ 270 BUFFER_TRACE(bh, "call jbd2_journal_revoke"); 271 err = jbd2_journal_revoke(handle, blocknr, bh); 272 if (err) { 273 ext4_journal_abort_handle(where, line, __func__, 274 bh, handle, err); 275 ext4_set_errno(inode->i_sb, -err); 276 __ext4_abort(inode->i_sb, where, line, 277 "error %d when attempting revoke", err); 278 } 279 BUFFER_TRACE(bh, "exit"); 280 return err; 281 } 282 283 int __ext4_journal_get_create_access(const char *where, unsigned int line, 284 handle_t *handle, struct buffer_head *bh) 285 { 286 int err = 0; 287 288 if (ext4_handle_valid(handle)) { 289 err = jbd2_journal_get_create_access(handle, bh); 290 if (err) 291 ext4_journal_abort_handle(where, line, __func__, 292 bh, handle, err); 293 } 294 return err; 295 } 296 297 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 298 handle_t *handle, struct inode *inode, 299 struct buffer_head *bh) 300 { 301 int err = 0; 302 303 might_sleep(); 304 305 set_buffer_meta(bh); 306 set_buffer_prio(bh); 307 if (ext4_handle_valid(handle)) { 308 err = jbd2_journal_dirty_metadata(handle, bh); 309 /* Errors can only happen due to aborted journal or a nasty bug */ 310 if (!is_handle_aborted(handle) && WARN_ON_ONCE(err)) { 311 ext4_journal_abort_handle(where, line, __func__, bh, 312 handle, err); 313 if (inode == NULL) { 314 pr_err("EXT4: jbd2_journal_dirty_metadata " 315 "failed: handle type %u started at " 316 "line %u, credits %u/%u, errcode %d", 317 handle->h_type, 318 handle->h_line_no, 319 handle->h_requested_credits, 320 jbd2_handle_buffer_credits(handle), err); 321 return err; 322 } 323 ext4_error_inode(inode, where, line, 324 bh->b_blocknr, 325 "journal_dirty_metadata failed: " 326 "handle type %u started at line %u, " 327 "credits %u/%u, errcode %d", 328 handle->h_type, 329 handle->h_line_no, 330 handle->h_requested_credits, 331 jbd2_handle_buffer_credits(handle), 332 err); 333 } 334 } else { 335 if (inode) 336 mark_buffer_dirty_inode(bh, inode); 337 else 338 mark_buffer_dirty(bh); 339 if (inode && inode_needs_sync(inode)) { 340 sync_dirty_buffer(bh); 341 if (buffer_req(bh) && !buffer_uptodate(bh)) { 342 struct ext4_super_block *es; 343 344 es = EXT4_SB(inode->i_sb)->s_es; 345 es->s_last_error_block = 346 cpu_to_le64(bh->b_blocknr); 347 ext4_set_errno(inode->i_sb, EIO); 348 ext4_error_inode(inode, where, line, 349 bh->b_blocknr, 350 "IO error syncing itable block"); 351 err = -EIO; 352 } 353 } 354 } 355 return err; 356 } 357 358 int __ext4_handle_dirty_super(const char *where, unsigned int line, 359 handle_t *handle, struct super_block *sb) 360 { 361 struct buffer_head *bh = EXT4_SB(sb)->s_sbh; 362 int err = 0; 363 364 ext4_superblock_csum_set(sb); 365 if (ext4_handle_valid(handle)) { 366 err = jbd2_journal_dirty_metadata(handle, bh); 367 if (err) 368 ext4_journal_abort_handle(where, line, __func__, 369 bh, handle, err); 370 } else 371 mark_buffer_dirty(bh); 372 return err; 373 } 374