Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0-or-later */
2 : /*
3 : * linux/include/linux/jbd2.h
4 : *
5 : * Written by Stephen C. Tweedie <sct@redhat.com>
6 : *
7 : * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved
8 : *
9 : * Definitions for transaction data structures for the buffer cache
10 : * filesystem journaling support.
11 : */
12 :
13 : #ifndef _LINUX_JBD2_H
14 : #define _LINUX_JBD2_H
15 :
16 : /* Allow this file to be included directly into e2fsprogs */
17 : #ifndef __KERNEL__
18 : #include "jfs_compat.h"
19 : #define JBD2_DEBUG
20 : #else
21 :
22 : #include <linux/types.h>
23 : #include <linux/buffer_head.h>
24 : #include <linux/journal-head.h>
25 : #include <linux/stddef.h>
26 : #include <linux/mutex.h>
27 : #include <linux/timer.h>
28 : #include <linux/slab.h>
29 : #include <linux/bit_spinlock.h>
30 : #include <linux/blkdev.h>
31 : #include <crypto/hash.h>
32 : #endif
33 :
34 : #define journal_oom_retry 1
35 :
36 : /*
37 : * Define JBD2_PARANIOD_IOFAIL to cause a kernel BUG() if ext4 finds
38 : * certain classes of error which can occur due to failed IOs. Under
39 : * normal use we want ext4 to continue after such errors, because
40 : * hardware _can_ fail, but for debugging purposes when running tests on
41 : * known-good hardware we may want to trap these errors.
42 : */
43 : #undef JBD2_PARANOID_IOFAIL
44 :
45 : /*
46 : * The default maximum commit age, in seconds.
47 : */
48 : #define JBD2_DEFAULT_MAX_COMMIT_AGE 5
49 :
50 : #ifdef CONFIG_JBD2_DEBUG
51 : /*
52 : * Define JBD2_EXPENSIVE_CHECKING to enable more expensive internal
53 : * consistency checks. By default we don't do this unless
54 : * CONFIG_JBD2_DEBUG is on.
55 : */
56 : #define JBD2_EXPENSIVE_CHECKING
57 : extern ushort jbd2_journal_enable_debug;
58 : void __jbd2_debug(int level, const char *file, const char *func,
59 : unsigned int line, const char *fmt, ...);
60 :
61 : #define jbd_debug(n, fmt, a...) \
62 : __jbd2_debug((n), __FILE__, __func__, __LINE__, (fmt), ##a)
63 : #else
64 : #define jbd_debug(n, fmt, a...) /**/
65 : #endif
66 :
67 : extern void *jbd2_alloc(size_t size, gfp_t flags);
68 : extern void jbd2_free(void *ptr, size_t size);
69 :
70 : #define JBD2_MIN_JOURNAL_BLOCKS 1024
71 : #define JBD2_DEFAULT_FAST_COMMIT_BLOCKS 256
72 :
73 : #ifdef __KERNEL__
74 :
75 : /**
76 : * typedef handle_t - The handle_t type represents a single atomic update being performed by some process.
77 : *
78 : * All filesystem modifications made by the process go
79 : * through this handle. Recursive operations (such as quota operations)
80 : * are gathered into a single update.
81 : *
82 : * The buffer credits field is used to account for journaled buffers
83 : * being modified by the running process. To ensure that there is
84 : * enough log space for all outstanding operations, we need to limit the
85 : * number of outstanding buffers possible at any time. When the
86 : * operation completes, any buffer credits not used are credited back to
87 : * the transaction, so that at all times we know how many buffers the
88 : * outstanding updates on a transaction might possibly touch.
89 : *
90 : * This is an opaque datatype.
91 : **/
92 : typedef struct jbd2_journal_handle handle_t; /* Atomic operation type */
93 :
94 :
95 : /**
96 : * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem.
97 : *
98 : * journal_t is linked to from the fs superblock structure.
99 : *
100 : * We use the journal_t to keep track of all outstanding transaction
101 : * activity on the filesystem, and to manage the state of the log
102 : * writing process.
103 : *
104 : * This is an opaque datatype.
105 : **/
106 : typedef struct journal_s journal_t; /* Journal control structure */
107 : #endif
108 :
109 : /*
110 : * Internal structures used by the logging mechanism:
111 : */
112 :
113 : #define JBD2_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */
114 :
115 : /*
116 : * On-disk structures
117 : */
118 :
119 : /*
120 : * Descriptor block types:
121 : */
122 :
123 : #define JBD2_DESCRIPTOR_BLOCK 1
124 : #define JBD2_COMMIT_BLOCK 2
125 : #define JBD2_SUPERBLOCK_V1 3
126 : #define JBD2_SUPERBLOCK_V2 4
127 : #define JBD2_REVOKE_BLOCK 5
128 :
129 : /*
130 : * Standard header for all descriptor blocks:
131 : */
132 : typedef struct journal_header_s
133 : {
134 : __be32 h_magic;
135 : __be32 h_blocktype;
136 : __be32 h_sequence;
137 : } journal_header_t;
138 :
139 : /*
140 : * Checksum types.
141 : */
142 : #define JBD2_CRC32_CHKSUM 1
143 : #define JBD2_MD5_CHKSUM 2
144 : #define JBD2_SHA1_CHKSUM 3
145 : #define JBD2_CRC32C_CHKSUM 4
146 :
147 : #define JBD2_CRC32_CHKSUM_SIZE 4
148 :
149 : #define JBD2_CHECKSUM_BYTES (32 / sizeof(u32))
150 : /*
151 : * Commit block header for storing transactional checksums:
152 : *
153 : * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum*
154 : * fields are used to store a checksum of the descriptor and data blocks.
155 : *
156 : * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum
157 : * field is used to store crc32c(uuid+commit_block). Each journal metadata
158 : * block gets its own checksum, and data block checksums are stored in
159 : * journal_block_tag (in the descriptor). The other h_chksum* fields are
160 : * not used.
161 : *
162 : * If FEATURE_INCOMPAT_CSUM_V3 is set, the descriptor block uses
163 : * journal_block_tag3_t to store a full 32-bit checksum. Everything else
164 : * is the same as v2.
165 : *
166 : * Checksum v1, v2, and v3 are mutually exclusive features.
167 : */
168 : struct commit_header {
169 : __be32 h_magic;
170 : __be32 h_blocktype;
171 : __be32 h_sequence;
172 : unsigned char h_chksum_type;
173 : unsigned char h_chksum_size;
174 : unsigned char h_padding[2];
175 : __be32 h_chksum[JBD2_CHECKSUM_BYTES];
176 : __be64 h_commit_sec;
177 : __be32 h_commit_nsec;
178 : };
179 :
180 : /*
181 : * The block tag: used to describe a single buffer in the journal.
182 : * t_blocknr_high is only used if INCOMPAT_64BIT is set, so this
183 : * raw struct shouldn't be used for pointer math or sizeof() - use
184 : * journal_tag_bytes(journal) instead to compute this.
185 : */
186 : typedef struct journal_block_tag3_s
187 : {
188 : __be32 t_blocknr; /* The on-disk block number */
189 : __be32 t_flags; /* See below */
190 : __be32 t_blocknr_high; /* most-significant high 32bits. */
191 : __be32 t_checksum; /* crc32c(uuid+seq+block) */
192 : } journal_block_tag3_t;
193 :
194 : typedef struct journal_block_tag_s
195 : {
196 : __be32 t_blocknr; /* The on-disk block number */
197 : __be16 t_checksum; /* truncated crc32c(uuid+seq+block) */
198 : __be16 t_flags; /* See below */
199 : __be32 t_blocknr_high; /* most-significant high 32bits. */
200 : } journal_block_tag_t;
201 :
202 : /* Tail of descriptor or revoke block, for checksumming */
203 : struct jbd2_journal_block_tail {
204 : __be32 t_checksum; /* crc32c(uuid+descr_block) */
205 : };
206 :
207 : /*
208 : * The revoke descriptor: used on disk to describe a series of blocks to
209 : * be revoked from the log
210 : */
211 : typedef struct jbd2_journal_revoke_header_s
212 : {
213 : journal_header_t r_header;
214 : __be32 r_count; /* Count of bytes used in the block */
215 : } jbd2_journal_revoke_header_t;
216 :
217 : /* Definitions for the journal tag flags word: */
218 : #define JBD2_FLAG_ESCAPE 1 /* on-disk block is escaped */
219 : #define JBD2_FLAG_SAME_UUID 2 /* block has same uuid as previous */
220 : #define JBD2_FLAG_DELETED 4 /* block deleted by this transaction */
221 : #define JBD2_FLAG_LAST_TAG 8 /* last tag in this descriptor block */
222 :
223 :
224 : /*
225 : * The journal superblock. All fields are in big-endian byte order.
226 : */
227 : typedef struct journal_superblock_s
228 : {
229 : /* 0x0000 */
230 : journal_header_t s_header;
231 :
232 : /* 0x000C */
233 : /* Static information describing the journal */
234 : __be32 s_blocksize; /* journal device blocksize */
235 : __be32 s_maxlen; /* total blocks in journal file */
236 : __be32 s_first; /* first block of log information */
237 :
238 : /* 0x0018 */
239 : /* Dynamic information describing the current state of the log */
240 : __be32 s_sequence; /* first commit ID expected in log */
241 : __be32 s_start; /* blocknr of start of log */
242 :
243 : /* 0x0020 */
244 : /* Error value, as set by jbd2_journal_abort(). */
245 : __be32 s_errno;
246 :
247 : /* 0x0024 */
248 : /* Remaining fields are only valid in a version-2 superblock */
249 : __be32 s_feature_compat; /* compatible feature set */
250 : __be32 s_feature_incompat; /* incompatible feature set */
251 : __be32 s_feature_ro_compat; /* readonly-compatible feature set */
252 : /* 0x0030 */
253 : __u8 s_uuid[16]; /* 128-bit uuid for journal */
254 :
255 : /* 0x0040 */
256 : __be32 s_nr_users; /* Nr of filesystems sharing log */
257 :
258 : __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/
259 :
260 : /* 0x0048 */
261 : __be32 s_max_transaction; /* Limit of journal blocks per trans.*/
262 : __be32 s_max_trans_data; /* Limit of data blocks per trans. */
263 :
264 : /* 0x0050 */
265 : __u8 s_checksum_type; /* checksum type */
266 : __u8 s_padding2[3];
267 : /* 0x0054 */
268 : __be32 s_num_fc_blks; /* Number of fast commit blocks */
269 : /* 0x0058 */
270 : __u32 s_padding[41];
271 : __be32 s_checksum; /* crc32c(superblock) */
272 :
273 : /* 0x0100 */
274 : __u8 s_users[16*48]; /* ids of all fs'es sharing the log */
275 : /* 0x0400 */
276 : } journal_superblock_t;
277 :
278 : /* Use the jbd2_{has,set,clear}_feature_* helpers; these will be removed */
279 : #define JBD2_HAS_COMPAT_FEATURE(j,mask) \
280 : ((j)->j_format_version >= 2 && \
281 : ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask))))
282 : #define JBD2_HAS_RO_COMPAT_FEATURE(j,mask) \
283 : ((j)->j_format_version >= 2 && \
284 : ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask))))
285 : #define JBD2_HAS_INCOMPAT_FEATURE(j,mask) \
286 : ((j)->j_format_version >= 2 && \
287 : ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask))))
288 :
289 : #define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001
290 :
291 : #define JBD2_FEATURE_INCOMPAT_REVOKE 0x00000001
292 : #define JBD2_FEATURE_INCOMPAT_64BIT 0x00000002
293 : #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT 0x00000004
294 : #define JBD2_FEATURE_INCOMPAT_CSUM_V2 0x00000008
295 : #define JBD2_FEATURE_INCOMPAT_CSUM_V3 0x00000010
296 : #define JBD2_FEATURE_INCOMPAT_FAST_COMMIT 0x00000020
297 :
298 : /* See "journal feature predicate functions" below */
299 :
300 : /* Features known to this kernel version: */
301 : #define JBD2_KNOWN_COMPAT_FEATURES JBD2_FEATURE_COMPAT_CHECKSUM
302 : #define JBD2_KNOWN_ROCOMPAT_FEATURES 0
303 : #define JBD2_KNOWN_INCOMPAT_FEATURES (JBD2_FEATURE_INCOMPAT_REVOKE | \
304 : JBD2_FEATURE_INCOMPAT_64BIT | \
305 : JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \
306 : JBD2_FEATURE_INCOMPAT_CSUM_V2 | \
307 : JBD2_FEATURE_INCOMPAT_CSUM_V3 | \
308 : JBD2_FEATURE_INCOMPAT_FAST_COMMIT)
309 :
310 : #ifdef __KERNEL__
311 :
312 : #include <linux/fs.h>
313 : #include <linux/sched.h>
314 :
315 : enum jbd_state_bits {
316 : BH_JBD /* Has an attached ext3 journal_head */
317 : = BH_PrivateStart,
318 : BH_JWrite, /* Being written to log (@@@ DEBUGGING) */
319 : BH_Freed, /* Has been freed (truncated) */
320 : BH_Revoked, /* Has been revoked from the log */
321 : BH_RevokeValid, /* Revoked flag is valid */
322 : BH_JBDDirty, /* Is dirty but journaled */
323 : BH_JournalHead, /* Pins bh->b_private and jh->b_bh */
324 : BH_Shadow, /* IO on shadow buffer is running */
325 : BH_Verified, /* Metadata block has been verified ok */
326 : BH_JBDPrivateStart, /* First bit available for private use by FS */
327 : };
328 :
329 40267 : BUFFER_FNS(JBD, jbd)
330 1980 : BUFFER_FNS(JWrite, jwrite)
331 16738 : BUFFER_FNS(JBDDirty, jbddirty)
332 15066 : TAS_BUFFER_FNS(JBDDirty, jbddirty)
333 1142 : BUFFER_FNS(Revoked, revoked)
334 1022 : TAS_BUFFER_FNS(Revoked, revoked)
335 77 : BUFFER_FNS(RevokeValid, revokevalid)
336 1933 : TAS_BUFFER_FNS(RevokeValid, revokevalid)
337 1878 : BUFFER_FNS(Freed, freed)
338 3728 : BUFFER_FNS(Shadow, shadow)
339 10032 : BUFFER_FNS(Verified, verified)
340 :
341 48184 : static inline struct buffer_head *jh2bh(struct journal_head *jh)
342 : {
343 48184 : return jh->b_bh;
344 : }
345 :
346 20589 : static inline struct journal_head *bh2jh(struct buffer_head *bh)
347 : {
348 20589 : return bh->b_private;
349 : }
350 :
351 11739 : static inline void jbd_lock_bh_journal_head(struct buffer_head *bh)
352 : {
353 11739 : bit_spin_lock(BH_JournalHead, &bh->b_state);
354 : }
355 :
356 11739 : static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh)
357 : {
358 11739 : bit_spin_unlock(BH_JournalHead, &bh->b_state);
359 4754 : }
360 :
361 : #define J_ASSERT(assert) BUG_ON(!(assert))
362 :
363 : #define J_ASSERT_BH(bh, expr) J_ASSERT(expr)
364 : #define J_ASSERT_JH(jh, expr) J_ASSERT(expr)
365 :
366 : #if defined(JBD2_PARANOID_IOFAIL)
367 : #define J_EXPECT(expr, why...) J_ASSERT(expr)
368 : #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr)
369 : #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr)
370 : #else
371 : #define __journal_expect(expr, why...) \
372 : ({ \
373 : int val = (expr); \
374 : if (!val) { \
375 : printk(KERN_ERR \
376 : "JBD2 unexpected failure: %s: %s;\n", \
377 : __func__, #expr); \
378 : printk(KERN_ERR why "\n"); \
379 : } \
380 : val; \
381 : })
382 : #define J_EXPECT(expr, why...) __journal_expect(expr, ## why)
383 : #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why)
384 : #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why)
385 : #endif
386 :
387 : /* Flags in jbd_inode->i_flags */
388 : #define __JI_COMMIT_RUNNING 0
389 : #define __JI_WRITE_DATA 1
390 : #define __JI_WAIT_DATA 2
391 :
392 : /*
393 : * Commit of the inode data in progress. We use this flag to protect us from
394 : * concurrent deletion of inode. We cannot use reference to inode for this
395 : * since we cannot afford doing last iput() on behalf of kjournald
396 : */
397 : #define JI_COMMIT_RUNNING (1 << __JI_COMMIT_RUNNING)
398 : /* Write allocated dirty buffers in this inode before commit */
399 : #define JI_WRITE_DATA (1 << __JI_WRITE_DATA)
400 : /* Wait for outstanding data writes for this inode before commit */
401 : #define JI_WAIT_DATA (1 << __JI_WAIT_DATA)
402 :
403 : /**
404 : * struct jbd2_inode - The jbd_inode type is the structure linking inodes in
405 : * ordered mode present in a transaction so that we can sync them during commit.
406 : */
407 : struct jbd2_inode {
408 : /**
409 : * @i_transaction:
410 : *
411 : * Which transaction does this inode belong to? Either the running
412 : * transaction or the committing one. [j_list_lock]
413 : */
414 : transaction_t *i_transaction;
415 :
416 : /**
417 : * @i_next_transaction:
418 : *
419 : * Pointer to the running transaction modifying inode's data in case
420 : * there is already a committing transaction touching it. [j_list_lock]
421 : */
422 : transaction_t *i_next_transaction;
423 :
424 : /**
425 : * @i_list: List of inodes in the i_transaction [j_list_lock]
426 : */
427 : struct list_head i_list;
428 :
429 : /**
430 : * @i_vfs_inode:
431 : *
432 : * VFS inode this inode belongs to [constant for lifetime of structure]
433 : */
434 : struct inode *i_vfs_inode;
435 :
436 : /**
437 : * @i_flags: Flags of inode [j_list_lock]
438 : */
439 : unsigned long i_flags;
440 :
441 : /**
442 : * @i_dirty_start:
443 : *
444 : * Offset in bytes where the dirty range for this inode starts.
445 : * [j_list_lock]
446 : */
447 : loff_t i_dirty_start;
448 :
449 : /**
450 : * @i_dirty_end:
451 : *
452 : * Inclusive offset in bytes where the dirty range for this inode
453 : * ends. [j_list_lock]
454 : */
455 : loff_t i_dirty_end;
456 : };
457 :
458 : struct jbd2_revoke_table_s;
459 :
460 : /**
461 : * struct jbd2_journal_handle - The jbd2_journal_handle type is the concrete
462 : * type associated with handle_t.
463 : * @h_transaction: Which compound transaction is this update a part of?
464 : * @h_journal: Which journal handle belongs to - used iff h_reserved set.
465 : * @h_rsv_handle: Handle reserved for finishing the logical operation.
466 : * @h_total_credits: Number of remaining buffers we are allowed to add to
467 : * journal. These are dirty buffers and revoke descriptor blocks.
468 : * @h_revoke_credits: Number of remaining revoke records available for handle
469 : * @h_ref: Reference count on this handle.
470 : * @h_err: Field for caller's use to track errors through large fs operations.
471 : * @h_sync: Flag for sync-on-close.
472 : * @h_jdata: Flag to force data journaling.
473 : * @h_reserved: Flag for handle for reserved credits.
474 : * @h_aborted: Flag indicating fatal error on handle.
475 : * @h_type: For handle statistics.
476 : * @h_line_no: For handle statistics.
477 : * @h_start_jiffies: Handle Start time.
478 : * @h_requested_credits: Holds @h_total_credits after handle is started.
479 : * @h_revoke_credits_requested: Holds @h_revoke_credits after handle is started.
480 : * @saved_alloc_context: Saved context while transaction is open.
481 : **/
482 :
483 : /* Docbook can't yet cope with the bit fields, but will leave the documentation
484 : * in so it can be fixed later.
485 : */
486 :
487 : struct jbd2_journal_handle
488 : {
489 : union {
490 : transaction_t *h_transaction;
491 : /* Which journal handle belongs to - used iff h_reserved set */
492 : journal_t *h_journal;
493 : };
494 :
495 : handle_t *h_rsv_handle;
496 : int h_total_credits;
497 : int h_revoke_credits;
498 : int h_revoke_credits_requested;
499 : int h_ref;
500 : int h_err;
501 :
502 : /* Flags [no locking] */
503 : unsigned int h_sync: 1;
504 : unsigned int h_jdata: 1;
505 : unsigned int h_reserved: 1;
506 : unsigned int h_aborted: 1;
507 : unsigned int h_type: 8;
508 : unsigned int h_line_no: 16;
509 :
510 : unsigned long h_start_jiffies;
511 : unsigned int h_requested_credits;
512 :
513 : unsigned int saved_alloc_context;
514 : };
515 :
516 :
517 : /*
518 : * Some stats for checkpoint phase
519 : */
520 : struct transaction_chp_stats_s {
521 : unsigned long cs_chp_time;
522 : __u32 cs_forced_to_close;
523 : __u32 cs_written;
524 : __u32 cs_dropped;
525 : };
526 :
527 : /* The transaction_t type is the guts of the journaling mechanism. It
528 : * tracks a compound transaction through its various states:
529 : *
530 : * RUNNING: accepting new updates
531 : * LOCKED: Updates still running but we don't accept new ones
532 : * RUNDOWN: Updates are tidying up but have finished requesting
533 : * new buffers to modify (state not used for now)
534 : * FLUSH: All updates complete, but we are still writing to disk
535 : * COMMIT: All data on disk, writing commit record
536 : * FINISHED: We still have to keep the transaction for checkpointing.
537 : *
538 : * The transaction keeps track of all of the buffers modified by a
539 : * running transaction, and all of the buffers committed but not yet
540 : * flushed to home for finished transactions.
541 : * (Locking Documentation improved by LockDoc)
542 : */
543 :
544 : /*
545 : * Lock ranking:
546 : *
547 : * j_list_lock
548 : * ->jbd_lock_bh_journal_head() (This is "innermost")
549 : *
550 : * j_state_lock
551 : * ->b_state_lock
552 : *
553 : * b_state_lock
554 : * ->j_list_lock
555 : *
556 : * j_state_lock
557 : * ->t_handle_lock
558 : *
559 : * j_state_lock
560 : * ->j_list_lock (journal_unmap_buffer)
561 : *
562 : */
563 :
564 : struct transaction_s
565 : {
566 : /* Pointer to the journal for this transaction. [no locking] */
567 : journal_t *t_journal;
568 :
569 : /* Sequence number for this transaction [no locking] */
570 : tid_t t_tid;
571 :
572 : /*
573 : * Transaction's current state
574 : * [no locking - only kjournald2 alters this]
575 : * [j_list_lock] guards transition of a transaction into T_FINISHED
576 : * state and subsequent call of __jbd2_journal_drop_transaction()
577 : * FIXME: needs barriers
578 : * KLUDGE: [use j_state_lock]
579 : */
580 : enum {
581 : T_RUNNING,
582 : T_LOCKED,
583 : T_SWITCH,
584 : T_FLUSH,
585 : T_COMMIT,
586 : T_COMMIT_DFLUSH,
587 : T_COMMIT_JFLUSH,
588 : T_COMMIT_CALLBACK,
589 : T_FINISHED
590 : } t_state;
591 :
592 : /*
593 : * Where in the log does this transaction's commit start? [no locking]
594 : */
595 : unsigned long t_log_start;
596 :
597 : /* Number of buffers on the t_buffers list [j_list_lock] */
598 : int t_nr_buffers;
599 :
600 : /*
601 : * Doubly-linked circular list of all buffers reserved but not yet
602 : * modified by this transaction [j_list_lock]
603 : */
604 : struct journal_head *t_reserved_list;
605 :
606 : /*
607 : * Doubly-linked circular list of all metadata buffers owned by this
608 : * transaction [j_list_lock]
609 : */
610 : struct journal_head *t_buffers;
611 :
612 : /*
613 : * Doubly-linked circular list of all forget buffers (superseded
614 : * buffers which we can un-checkpoint once this transaction commits)
615 : * [j_list_lock]
616 : */
617 : struct journal_head *t_forget;
618 :
619 : /*
620 : * Doubly-linked circular list of all buffers still to be flushed before
621 : * this transaction can be checkpointed. [j_list_lock]
622 : */
623 : struct journal_head *t_checkpoint_list;
624 :
625 : /*
626 : * Doubly-linked circular list of all buffers submitted for IO while
627 : * checkpointing. [j_list_lock]
628 : */
629 : struct journal_head *t_checkpoint_io_list;
630 :
631 : /*
632 : * Doubly-linked circular list of metadata buffers being shadowed by log
633 : * IO. The IO buffers on the iobuf list and the shadow buffers on this
634 : * list match each other one for one at all times. [j_list_lock]
635 : */
636 : struct journal_head *t_shadow_list;
637 :
638 : /*
639 : * List of inodes associated with the transaction; e.g., ext4 uses
640 : * this to track inodes in data=ordered and data=journal mode that
641 : * need special handling on transaction commit; also used by ocfs2.
642 : * [j_list_lock]
643 : */
644 : struct list_head t_inode_list;
645 :
646 : /*
647 : * Protects info related to handles
648 : */
649 : spinlock_t t_handle_lock;
650 :
651 : /*
652 : * Longest time some handle had to wait for running transaction
653 : */
654 : unsigned long t_max_wait;
655 :
656 : /*
657 : * When transaction started
658 : */
659 : unsigned long t_start;
660 :
661 : /*
662 : * When commit was requested [j_state_lock]
663 : */
664 : unsigned long t_requested;
665 :
666 : /*
667 : * Checkpointing stats [j_list_lock]
668 : */
669 : struct transaction_chp_stats_s t_chp_stats;
670 :
671 : /*
672 : * Number of outstanding updates running on this transaction
673 : * [none]
674 : */
675 : atomic_t t_updates;
676 :
677 : /*
678 : * Number of blocks reserved for this transaction in the journal.
679 : * This is including all credits reserved when starting transaction
680 : * handles as well as all journal descriptor blocks needed for this
681 : * transaction. [none]
682 : */
683 : atomic_t t_outstanding_credits;
684 :
685 : /*
686 : * Number of revoke records for this transaction added by already
687 : * stopped handles. [none]
688 : */
689 : atomic_t t_outstanding_revokes;
690 :
691 : /*
692 : * How many handles used this transaction? [none]
693 : */
694 : atomic_t t_handle_count;
695 :
696 : /*
697 : * Forward and backward links for the circular list of all transactions
698 : * awaiting checkpoint. [j_list_lock]
699 : */
700 : transaction_t *t_cpnext, *t_cpprev;
701 :
702 : /*
703 : * When will the transaction expire (become due for commit), in jiffies?
704 : * [no locking]
705 : */
706 : unsigned long t_expires;
707 :
708 : /*
709 : * When this transaction started, in nanoseconds [no locking]
710 : */
711 : ktime_t t_start_time;
712 :
713 : /*
714 : * This transaction is being forced and some process is
715 : * waiting for it to finish.
716 : */
717 : unsigned int t_synchronous_commit:1;
718 :
719 : /* Disk flush needs to be sent to fs partition [no locking] */
720 : int t_need_data_flush;
721 :
722 : /*
723 : * For use by the filesystem to store fs-specific data
724 : * structures associated with the transaction
725 : */
726 : struct list_head t_private_list;
727 : };
728 :
729 : struct transaction_run_stats_s {
730 : unsigned long rs_wait;
731 : unsigned long rs_request_delay;
732 : unsigned long rs_running;
733 : unsigned long rs_locked;
734 : unsigned long rs_flushing;
735 : unsigned long rs_logging;
736 :
737 : __u32 rs_handle_count;
738 : __u32 rs_blocks;
739 : __u32 rs_blocks_logged;
740 : };
741 :
742 : struct transaction_stats_s {
743 : unsigned long ts_tid;
744 : unsigned long ts_requested;
745 : struct transaction_run_stats_s run;
746 : };
747 :
748 : static inline unsigned long
749 2058 : jbd2_time_diff(unsigned long start, unsigned long end)
750 : {
751 2058 : if (end >= start)
752 2058 : return end - start;
753 :
754 0 : return end + (MAX_JIFFY_OFFSET - start);
755 : }
756 :
757 : #define JBD2_NR_BATCH 64
758 :
759 : enum passtype {PASS_SCAN, PASS_REVOKE, PASS_REPLAY};
760 :
761 : #define JBD2_FC_REPLAY_STOP 0
762 : #define JBD2_FC_REPLAY_CONTINUE 1
763 :
764 : /**
765 : * struct journal_s - The journal_s type is the concrete type associated with
766 : * journal_t.
767 : */
768 : struct journal_s
769 : {
770 : /**
771 : * @j_flags: General journaling state flags [j_state_lock]
772 : */
773 : unsigned long j_flags;
774 :
775 : /**
776 : * @j_errno:
777 : *
778 : * Is there an outstanding uncleared error on the journal (from a prior
779 : * abort)? [j_state_lock]
780 : */
781 : int j_errno;
782 :
783 : /**
784 : * @j_abort_mutex: Lock the whole aborting procedure.
785 : */
786 : struct mutex j_abort_mutex;
787 :
788 : /**
789 : * @j_sb_buffer: The first part of the superblock buffer.
790 : */
791 : struct buffer_head *j_sb_buffer;
792 :
793 : /**
794 : * @j_superblock: The second part of the superblock buffer.
795 : */
796 : journal_superblock_t *j_superblock;
797 :
798 : /**
799 : * @j_format_version: Version of the superblock format.
800 : */
801 : int j_format_version;
802 :
803 : /**
804 : * @j_state_lock: Protect the various scalars in the journal.
805 : */
806 : rwlock_t j_state_lock;
807 :
808 : /**
809 : * @j_barrier_count:
810 : *
811 : * Number of processes waiting to create a barrier lock [j_state_lock]
812 : */
813 : int j_barrier_count;
814 :
815 : /**
816 : * @j_barrier: The barrier lock itself.
817 : */
818 : struct mutex j_barrier;
819 :
820 : /**
821 : * @j_running_transaction:
822 : *
823 : * Transactions: The current running transaction...
824 : * [j_state_lock] [caller holding open handle]
825 : */
826 : transaction_t *j_running_transaction;
827 :
828 : /**
829 : * @j_committing_transaction:
830 : *
831 : * the transaction we are pushing to disk
832 : * [j_state_lock] [caller holding open handle]
833 : */
834 : transaction_t *j_committing_transaction;
835 :
836 : /**
837 : * @j_checkpoint_transactions:
838 : *
839 : * ... and a linked circular list of all transactions waiting for
840 : * checkpointing. [j_list_lock]
841 : */
842 : transaction_t *j_checkpoint_transactions;
843 :
844 : /**
845 : * @j_wait_transaction_locked:
846 : *
847 : * Wait queue for waiting for a locked transaction to start committing,
848 : * or for a barrier lock to be released.
849 : */
850 : wait_queue_head_t j_wait_transaction_locked;
851 :
852 : /**
853 : * @j_wait_done_commit: Wait queue for waiting for commit to complete.
854 : */
855 : wait_queue_head_t j_wait_done_commit;
856 :
857 : /**
858 : * @j_wait_commit: Wait queue to trigger commit.
859 : */
860 : wait_queue_head_t j_wait_commit;
861 :
862 : /**
863 : * @j_wait_updates: Wait queue to wait for updates to complete.
864 : */
865 : wait_queue_head_t j_wait_updates;
866 :
867 : /**
868 : * @j_wait_reserved:
869 : *
870 : * Wait queue to wait for reserved buffer credits to drop.
871 : */
872 : wait_queue_head_t j_wait_reserved;
873 :
874 : /**
875 : * @j_fc_wait:
876 : *
877 : * Wait queue to wait for completion of async fast commits.
878 : */
879 : wait_queue_head_t j_fc_wait;
880 :
881 : /**
882 : * @j_checkpoint_mutex:
883 : *
884 : * Semaphore for locking against concurrent checkpoints.
885 : */
886 : struct mutex j_checkpoint_mutex;
887 :
888 : /**
889 : * @j_chkpt_bhs:
890 : *
891 : * List of buffer heads used by the checkpoint routine. This
892 : * was moved from jbd2_log_do_checkpoint() to reduce stack
893 : * usage. Access to this array is controlled by the
894 : * @j_checkpoint_mutex. [j_checkpoint_mutex]
895 : */
896 : struct buffer_head *j_chkpt_bhs[JBD2_NR_BATCH];
897 :
898 : /**
899 : * @j_head:
900 : *
901 : * Journal head: identifies the first unused block in the journal.
902 : * [j_state_lock]
903 : */
904 : unsigned long j_head;
905 :
906 : /**
907 : * @j_tail:
908 : *
909 : * Journal tail: identifies the oldest still-used block in the journal.
910 : * [j_state_lock]
911 : */
912 : unsigned long j_tail;
913 :
914 : /**
915 : * @j_free:
916 : *
917 : * Journal free: how many free blocks are there in the journal?
918 : * [j_state_lock]
919 : */
920 : unsigned long j_free;
921 :
922 : /**
923 : * @j_first:
924 : *
925 : * The block number of the first usable block in the journal
926 : * [j_state_lock].
927 : */
928 : unsigned long j_first;
929 :
930 : /**
931 : * @j_last:
932 : *
933 : * The block number one beyond the last usable block in the journal
934 : * [j_state_lock].
935 : */
936 : unsigned long j_last;
937 :
938 : /**
939 : * @j_fc_first:
940 : *
941 : * The block number of the first fast commit block in the journal
942 : * [j_state_lock].
943 : */
944 : unsigned long j_fc_first;
945 :
946 : /**
947 : * @j_fc_off:
948 : *
949 : * Number of fast commit blocks currently allocated. Accessed only
950 : * during fast commit. Currently only process can do fast commit, so
951 : * this field is not protected by any lock.
952 : */
953 : unsigned long j_fc_off;
954 :
955 : /**
956 : * @j_fc_last:
957 : *
958 : * The block number one beyond the last fast commit block in the journal
959 : * [j_state_lock].
960 : */
961 : unsigned long j_fc_last;
962 :
963 : /**
964 : * @j_dev: Device where we store the journal.
965 : */
966 : struct block_device *j_dev;
967 :
968 : /**
969 : * @j_blocksize: Block size for the location where we store the journal.
970 : */
971 : int j_blocksize;
972 :
973 : /**
974 : * @j_blk_offset:
975 : *
976 : * Starting block offset into the device where we store the journal.
977 : */
978 : unsigned long long j_blk_offset;
979 :
980 : /**
981 : * @j_devname: Journal device name.
982 : */
983 : char j_devname[BDEVNAME_SIZE+24];
984 :
985 : /**
986 : * @j_fs_dev:
987 : *
988 : * Device which holds the client fs. For internal journal this will be
989 : * equal to j_dev.
990 : */
991 : struct block_device *j_fs_dev;
992 :
993 : /**
994 : * @j_total_len: Total maximum capacity of the journal region on disk.
995 : */
996 : unsigned int j_total_len;
997 :
998 : /**
999 : * @j_reserved_credits:
1000 : *
1001 : * Number of buffers reserved from the running transaction.
1002 : */
1003 : atomic_t j_reserved_credits;
1004 :
1005 : /**
1006 : * @j_list_lock: Protects the buffer lists and internal buffer state.
1007 : */
1008 : spinlock_t j_list_lock;
1009 :
1010 : /**
1011 : * @j_inode:
1012 : *
1013 : * Optional inode where we store the journal. If present, all
1014 : * journal block numbers are mapped into this inode via bmap().
1015 : */
1016 : struct inode *j_inode;
1017 :
1018 : /**
1019 : * @j_tail_sequence:
1020 : *
1021 : * Sequence number of the oldest transaction in the log [j_state_lock]
1022 : */
1023 : tid_t j_tail_sequence;
1024 :
1025 : /**
1026 : * @j_transaction_sequence:
1027 : *
1028 : * Sequence number of the next transaction to grant [j_state_lock]
1029 : */
1030 : tid_t j_transaction_sequence;
1031 :
1032 : /**
1033 : * @j_commit_sequence:
1034 : *
1035 : * Sequence number of the most recently committed transaction
1036 : * [j_state_lock].
1037 : */
1038 : tid_t j_commit_sequence;
1039 :
1040 : /**
1041 : * @j_commit_request:
1042 : *
1043 : * Sequence number of the most recent transaction wanting commit
1044 : * [j_state_lock]
1045 : */
1046 : tid_t j_commit_request;
1047 :
1048 : /**
1049 : * @j_uuid:
1050 : *
1051 : * Journal uuid: identifies the object (filesystem, LVM volume etc)
1052 : * backed by this journal. This will eventually be replaced by an array
1053 : * of uuids, allowing us to index multiple devices within a single
1054 : * journal and to perform atomic updates across them.
1055 : */
1056 : __u8 j_uuid[16];
1057 :
1058 : /**
1059 : * @j_task: Pointer to the current commit thread for this journal.
1060 : */
1061 : struct task_struct *j_task;
1062 :
1063 : /**
1064 : * @j_max_transaction_buffers:
1065 : *
1066 : * Maximum number of metadata buffers to allow in a single compound
1067 : * commit transaction.
1068 : */
1069 : int j_max_transaction_buffers;
1070 :
1071 : /**
1072 : * @j_revoke_records_per_block:
1073 : *
1074 : * Number of revoke records that fit in one descriptor block.
1075 : */
1076 : int j_revoke_records_per_block;
1077 :
1078 : /**
1079 : * @j_commit_interval:
1080 : *
1081 : * What is the maximum transaction lifetime before we begin a commit?
1082 : */
1083 : unsigned long j_commit_interval;
1084 :
1085 : /**
1086 : * @j_commit_timer: The timer used to wakeup the commit thread.
1087 : */
1088 : struct timer_list j_commit_timer;
1089 :
1090 : /**
1091 : * @j_revoke_lock: Protect the revoke table.
1092 : */
1093 : spinlock_t j_revoke_lock;
1094 :
1095 : /**
1096 : * @j_revoke:
1097 : *
1098 : * The revoke table - maintains the list of revoked blocks in the
1099 : * current transaction.
1100 : */
1101 : struct jbd2_revoke_table_s *j_revoke;
1102 :
1103 : /**
1104 : * @j_revoke_table: Alternate revoke tables for j_revoke.
1105 : */
1106 : struct jbd2_revoke_table_s *j_revoke_table[2];
1107 :
1108 : /**
1109 : * @j_wbuf: Array of bhs for jbd2_journal_commit_transaction.
1110 : */
1111 : struct buffer_head **j_wbuf;
1112 :
1113 : /**
1114 : * @j_fc_wbuf: Array of fast commit bhs for fast commit. Accessed only
1115 : * during a fast commit. Currently only process can do fast commit, so
1116 : * this field is not protected by any lock.
1117 : */
1118 : struct buffer_head **j_fc_wbuf;
1119 :
1120 : /**
1121 : * @j_wbufsize:
1122 : *
1123 : * Size of @j_wbuf array.
1124 : */
1125 : int j_wbufsize;
1126 :
1127 : /**
1128 : * @j_fc_wbufsize:
1129 : *
1130 : * Size of @j_fc_wbuf array.
1131 : */
1132 : int j_fc_wbufsize;
1133 :
1134 : /**
1135 : * @j_last_sync_writer:
1136 : *
1137 : * The pid of the last person to run a synchronous operation
1138 : * through the journal.
1139 : */
1140 : pid_t j_last_sync_writer;
1141 :
1142 : /**
1143 : * @j_average_commit_time:
1144 : *
1145 : * The average amount of time in nanoseconds it takes to commit a
1146 : * transaction to disk. [j_state_lock]
1147 : */
1148 : u64 j_average_commit_time;
1149 :
1150 : /**
1151 : * @j_min_batch_time:
1152 : *
1153 : * Minimum time that we should wait for additional filesystem operations
1154 : * to get batched into a synchronous handle in microseconds.
1155 : */
1156 : u32 j_min_batch_time;
1157 :
1158 : /**
1159 : * @j_max_batch_time:
1160 : *
1161 : * Maximum time that we should wait for additional filesystem operations
1162 : * to get batched into a synchronous handle in microseconds.
1163 : */
1164 : u32 j_max_batch_time;
1165 :
1166 : /**
1167 : * @j_commit_callback:
1168 : *
1169 : * This function is called when a transaction is closed.
1170 : */
1171 : void (*j_commit_callback)(journal_t *,
1172 : transaction_t *);
1173 :
1174 : /**
1175 : * @j_submit_inode_data_buffers:
1176 : *
1177 : * This function is called for all inodes associated with the
1178 : * committing transaction marked with JI_WRITE_DATA flag
1179 : * before we start to write out the transaction to the journal.
1180 : */
1181 : int (*j_submit_inode_data_buffers)
1182 : (struct jbd2_inode *);
1183 :
1184 : /**
1185 : * @j_finish_inode_data_buffers:
1186 : *
1187 : * This function is called for all inodes associated with the
1188 : * committing transaction marked with JI_WAIT_DATA flag
1189 : * after we have written the transaction to the journal
1190 : * but before we write out the commit block.
1191 : */
1192 : int (*j_finish_inode_data_buffers)
1193 : (struct jbd2_inode *);
1194 :
1195 : /*
1196 : * Journal statistics
1197 : */
1198 :
1199 : /**
1200 : * @j_history_lock: Protect the transactions statistics history.
1201 : */
1202 : spinlock_t j_history_lock;
1203 :
1204 : /**
1205 : * @j_proc_entry: procfs entry for the jbd statistics directory.
1206 : */
1207 : struct proc_dir_entry *j_proc_entry;
1208 :
1209 : /**
1210 : * @j_stats: Overall statistics.
1211 : */
1212 : struct transaction_stats_s j_stats;
1213 :
1214 : /**
1215 : * @j_failed_commit: Failed journal commit ID.
1216 : */
1217 : unsigned int j_failed_commit;
1218 :
1219 : /**
1220 : * @j_private:
1221 : *
1222 : * An opaque pointer to fs-private information. ext3 puts its
1223 : * superblock pointer here.
1224 : */
1225 : void *j_private;
1226 :
1227 : /**
1228 : * @j_chksum_driver:
1229 : *
1230 : * Reference to checksum algorithm driver via cryptoapi.
1231 : */
1232 : struct crypto_shash *j_chksum_driver;
1233 :
1234 : /**
1235 : * @j_csum_seed:
1236 : *
1237 : * Precomputed journal UUID checksum for seeding other checksums.
1238 : */
1239 : __u32 j_csum_seed;
1240 :
1241 : #ifdef CONFIG_DEBUG_LOCK_ALLOC
1242 : /**
1243 : * @j_trans_commit_map:
1244 : *
1245 : * Lockdep entity to track transaction commit dependencies. Handles
1246 : * hold this "lock" for read, when we wait for commit, we acquire the
1247 : * "lock" for writing. This matches the properties of jbd2 journalling
1248 : * where the running transaction has to wait for all handles to be
1249 : * dropped to commit that transaction and also acquiring a handle may
1250 : * require transaction commit to finish.
1251 : */
1252 : struct lockdep_map j_trans_commit_map;
1253 : #endif
1254 :
1255 : /**
1256 : * @j_fc_cleanup_callback:
1257 : *
1258 : * Clean-up after fast commit or full commit. JBD2 calls this function
1259 : * after every commit operation.
1260 : */
1261 : void (*j_fc_cleanup_callback)(struct journal_s *journal, int);
1262 :
1263 : /**
1264 : * @j_fc_replay_callback:
1265 : *
1266 : * File-system specific function that performs replay of a fast
1267 : * commit. JBD2 calls this function for each fast commit block found in
1268 : * the journal. This function should return JBD2_FC_REPLAY_CONTINUE
1269 : * to indicate that the block was processed correctly and more fast
1270 : * commit replay should continue. Return value of JBD2_FC_REPLAY_STOP
1271 : * indicates the end of replay (no more blocks remaining). A negative
1272 : * return value indicates error.
1273 : */
1274 : int (*j_fc_replay_callback)(struct journal_s *journal,
1275 : struct buffer_head *bh,
1276 : enum passtype pass, int off,
1277 : tid_t expected_commit_id);
1278 : };
1279 :
1280 : #define jbd2_might_wait_for_commit(j) \
1281 : do { \
1282 : rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \
1283 : rwsem_release(&j->j_trans_commit_map, _THIS_IP_); \
1284 : } while (0)
1285 :
1286 : /* journal feature predicate functions */
1287 : #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \
1288 : static inline bool jbd2_has_feature_##name(journal_t *j) \
1289 : { \
1290 : return ((j)->j_format_version >= 2 && \
1291 : ((j)->j_superblock->s_feature_compat & \
1292 : cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname)) != 0); \
1293 : } \
1294 : static inline void jbd2_set_feature_##name(journal_t *j) \
1295 : { \
1296 : (j)->j_superblock->s_feature_compat |= \
1297 : cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1298 : } \
1299 : static inline void jbd2_clear_feature_##name(journal_t *j) \
1300 : { \
1301 : (j)->j_superblock->s_feature_compat &= \
1302 : ~cpu_to_be32(JBD2_FEATURE_COMPAT_##flagname); \
1303 : }
1304 :
1305 : #define JBD2_FEATURE_RO_COMPAT_FUNCS(name, flagname) \
1306 : static inline bool jbd2_has_feature_##name(journal_t *j) \
1307 : { \
1308 : return ((j)->j_format_version >= 2 && \
1309 : ((j)->j_superblock->s_feature_ro_compat & \
1310 : cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname)) != 0); \
1311 : } \
1312 : static inline void jbd2_set_feature_##name(journal_t *j) \
1313 : { \
1314 : (j)->j_superblock->s_feature_ro_compat |= \
1315 : cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1316 : } \
1317 : static inline void jbd2_clear_feature_##name(journal_t *j) \
1318 : { \
1319 : (j)->j_superblock->s_feature_ro_compat &= \
1320 : ~cpu_to_be32(JBD2_FEATURE_RO_COMPAT_##flagname); \
1321 : }
1322 :
1323 : #define JBD2_FEATURE_INCOMPAT_FUNCS(name, flagname) \
1324 : static inline bool jbd2_has_feature_##name(journal_t *j) \
1325 : { \
1326 : return ((j)->j_format_version >= 2 && \
1327 : ((j)->j_superblock->s_feature_incompat & \
1328 : cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname)) != 0); \
1329 : } \
1330 : static inline void jbd2_set_feature_##name(journal_t *j) \
1331 : { \
1332 : (j)->j_superblock->s_feature_incompat |= \
1333 : cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1334 : } \
1335 : static inline void jbd2_clear_feature_##name(journal_t *j) \
1336 : { \
1337 : (j)->j_superblock->s_feature_incompat &= \
1338 : ~cpu_to_be32(JBD2_FEATURE_INCOMPAT_##flagname); \
1339 : }
1340 :
1341 3920 : JBD2_FEATURE_COMPAT_FUNCS(checksum, CHECKSUM)
1342 :
1343 : JBD2_FEATURE_INCOMPAT_FUNCS(revoke, REVOKE)
1344 4236 : JBD2_FEATURE_INCOMPAT_FUNCS(64bit, 64BIT)
1345 464 : JBD2_FEATURE_INCOMPAT_FUNCS(async_commit, ASYNC_COMMIT)
1346 2406 : JBD2_FEATURE_INCOMPAT_FUNCS(csum2, CSUM_V2)
1347 2404 : JBD2_FEATURE_INCOMPAT_FUNCS(csum3, CSUM_V3)
1348 5 : JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit, FAST_COMMIT)
1349 :
1350 : /*
1351 : * Journal flag definitions
1352 : */
1353 : #define JBD2_UNMOUNT 0x001 /* Journal thread is being destroyed */
1354 : #define JBD2_ABORT 0x002 /* Journaling has been aborted for errors. */
1355 : #define JBD2_ACK_ERR 0x004 /* The errno in the sb has been acked */
1356 : #define JBD2_FLUSHED 0x008 /* The journal superblock has been flushed */
1357 : #define JBD2_LOADED 0x010 /* The journal superblock has been loaded */
1358 : #define JBD2_BARRIER 0x020 /* Use IDE barriers */
1359 : #define JBD2_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file
1360 : * data write error in ordered
1361 : * mode */
1362 : #define JBD2_FAST_COMMIT_ONGOING 0x100 /* Fast commit is ongoing */
1363 : #define JBD2_FULL_COMMIT_ONGOING 0x200 /* Full commit is ongoing */
1364 :
1365 : /*
1366 : * Function declarations for the journaling transaction and buffer
1367 : * management
1368 : */
1369 :
1370 : /* Filing buffers */
1371 : extern void jbd2_journal_unfile_buffer(journal_t *, struct journal_head *);
1372 : extern bool __jbd2_journal_refile_buffer(struct journal_head *);
1373 : extern void jbd2_journal_refile_buffer(journal_t *, struct journal_head *);
1374 : extern void __jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1375 : extern void __journal_free_buffer(struct journal_head *bh);
1376 : extern void jbd2_journal_file_buffer(struct journal_head *, transaction_t *, int);
1377 : extern void __journal_clean_data_list(transaction_t *transaction);
1378 1912 : static inline void jbd2_file_log_bh(struct list_head *head, struct buffer_head *bh)
1379 : {
1380 1912 : list_add_tail(&bh->b_assoc_buffers, head);
1381 58 : }
1382 1912 : static inline void jbd2_unfile_log_bh(struct buffer_head *bh)
1383 : {
1384 1912 : list_del_init(&bh->b_assoc_buffers);
1385 : }
1386 :
1387 : /* Log buffer allocation */
1388 : struct buffer_head *jbd2_journal_get_descriptor_buffer(transaction_t *, int);
1389 : void jbd2_descriptor_block_csum_set(journal_t *, struct buffer_head *);
1390 : int jbd2_journal_next_log_block(journal_t *, unsigned long long *);
1391 : int jbd2_journal_get_log_tail(journal_t *journal, tid_t *tid,
1392 : unsigned long *block);
1393 : int __jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1394 : void jbd2_update_log_tail(journal_t *journal, tid_t tid, unsigned long block);
1395 :
1396 : /* Commit management */
1397 : extern void jbd2_journal_commit_transaction(journal_t *);
1398 :
1399 : /* Checkpoint list management */
1400 : void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy);
1401 : int __jbd2_journal_remove_checkpoint(struct journal_head *);
1402 : void jbd2_journal_destroy_checkpoint(journal_t *journal);
1403 : void __jbd2_journal_insert_checkpoint(struct journal_head *, transaction_t *);
1404 :
1405 :
1406 : /*
1407 : * Triggers
1408 : */
1409 :
1410 : struct jbd2_buffer_trigger_type {
1411 : /*
1412 : * Fired a the moment data to write to the journal are known to be
1413 : * stable - so either at the moment b_frozen_data is created or just
1414 : * before a buffer is written to the journal. mapped_data is a mapped
1415 : * buffer that is the frozen data for commit.
1416 : */
1417 : void (*t_frozen)(struct jbd2_buffer_trigger_type *type,
1418 : struct buffer_head *bh, void *mapped_data,
1419 : size_t size);
1420 :
1421 : /*
1422 : * Fired during journal abort for dirty buffers that will not be
1423 : * committed.
1424 : */
1425 : void (*t_abort)(struct jbd2_buffer_trigger_type *type,
1426 : struct buffer_head *bh);
1427 : };
1428 :
1429 : extern void jbd2_buffer_frozen_trigger(struct journal_head *jh,
1430 : void *mapped_data,
1431 : struct jbd2_buffer_trigger_type *triggers);
1432 : extern void jbd2_buffer_abort_trigger(struct journal_head *jh,
1433 : struct jbd2_buffer_trigger_type *triggers);
1434 :
1435 : /* Buffer IO */
1436 : extern int jbd2_journal_write_metadata_buffer(transaction_t *transaction,
1437 : struct journal_head *jh_in,
1438 : struct buffer_head **bh_out,
1439 : sector_t blocknr);
1440 :
1441 : /* Transaction locking */
1442 : extern void __wait_on_journal (journal_t *);
1443 :
1444 : /* Transaction cache support */
1445 : extern void jbd2_journal_destroy_transaction_cache(void);
1446 : extern int __init jbd2_journal_init_transaction_cache(void);
1447 : extern void jbd2_journal_free_transaction(transaction_t *);
1448 :
1449 : /*
1450 : * Journal locking.
1451 : *
1452 : * We need to lock the journal during transaction state changes so that nobody
1453 : * ever tries to take a handle on the running transaction while we are in the
1454 : * middle of moving it to the commit phase. j_state_lock does this.
1455 : *
1456 : * Note that the locking is completely interrupt unsafe. We never touch
1457 : * journal structures from interrupts.
1458 : */
1459 :
1460 19945 : static inline handle_t *journal_current_handle(void)
1461 : {
1462 19945 : return current->journal_info;
1463 : }
1464 :
1465 : /* The journaling code user interface:
1466 : *
1467 : * Create and destroy handles
1468 : * Register buffer modifications against the current transaction.
1469 : */
1470 :
1471 : extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
1472 : extern handle_t *jbd2__journal_start(journal_t *, int blocks, int rsv_blocks,
1473 : int revoke_records, gfp_t gfp_mask,
1474 : unsigned int type, unsigned int line_no);
1475 : extern int jbd2_journal_restart(handle_t *, int nblocks);
1476 : extern int jbd2__journal_restart(handle_t *, int nblocks,
1477 : int revoke_records, gfp_t gfp_mask);
1478 : extern int jbd2_journal_start_reserved(handle_t *handle,
1479 : unsigned int type, unsigned int line_no);
1480 : extern void jbd2_journal_free_reserved(handle_t *handle);
1481 : extern int jbd2_journal_extend(handle_t *handle, int nblocks,
1482 : int revoke_records);
1483 : extern int jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
1484 : extern int jbd2_journal_get_create_access (handle_t *, struct buffer_head *);
1485 : extern int jbd2_journal_get_undo_access(handle_t *, struct buffer_head *);
1486 : void jbd2_journal_set_triggers(struct buffer_head *,
1487 : struct jbd2_buffer_trigger_type *type);
1488 : extern int jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
1489 : extern int jbd2_journal_forget (handle_t *, struct buffer_head *);
1490 : extern int jbd2_journal_invalidatepage(journal_t *,
1491 : struct page *, unsigned int, unsigned int);
1492 : extern int jbd2_journal_try_to_free_buffers(journal_t *journal, struct page *page);
1493 : extern int jbd2_journal_stop(handle_t *);
1494 : extern int jbd2_journal_flush (journal_t *);
1495 : extern void jbd2_journal_lock_updates (journal_t *);
1496 : extern void jbd2_journal_unlock_updates (journal_t *);
1497 :
1498 : extern journal_t * jbd2_journal_init_dev(struct block_device *bdev,
1499 : struct block_device *fs_dev,
1500 : unsigned long long start, int len, int bsize);
1501 : extern journal_t * jbd2_journal_init_inode (struct inode *);
1502 : extern int jbd2_journal_update_format (journal_t *);
1503 : extern int jbd2_journal_check_used_features
1504 : (journal_t *, unsigned long, unsigned long, unsigned long);
1505 : extern int jbd2_journal_check_available_features
1506 : (journal_t *, unsigned long, unsigned long, unsigned long);
1507 : extern int jbd2_journal_set_features
1508 : (journal_t *, unsigned long, unsigned long, unsigned long);
1509 : extern void jbd2_journal_clear_features
1510 : (journal_t *, unsigned long, unsigned long, unsigned long);
1511 : extern int jbd2_journal_load (journal_t *journal);
1512 : extern int jbd2_journal_destroy (journal_t *);
1513 : extern int jbd2_journal_recover (journal_t *journal);
1514 : extern int jbd2_journal_wipe (journal_t *, int);
1515 : extern int jbd2_journal_skip_recovery (journal_t *);
1516 : extern void jbd2_journal_update_sb_errno(journal_t *);
1517 : extern int jbd2_journal_update_sb_log_tail (journal_t *, tid_t,
1518 : unsigned long, int);
1519 : extern void jbd2_journal_abort (journal_t *, int);
1520 : extern int jbd2_journal_errno (journal_t *);
1521 : extern void jbd2_journal_ack_err (journal_t *);
1522 : extern int jbd2_journal_clear_err (journal_t *);
1523 : extern int jbd2_journal_bmap(journal_t *, unsigned long, unsigned long long *);
1524 : extern int jbd2_journal_force_commit(journal_t *);
1525 : extern int jbd2_journal_force_commit_nested(journal_t *);
1526 : extern int jbd2_journal_inode_ranged_write(handle_t *handle,
1527 : struct jbd2_inode *inode, loff_t start_byte,
1528 : loff_t length);
1529 : extern int jbd2_journal_inode_ranged_wait(handle_t *handle,
1530 : struct jbd2_inode *inode, loff_t start_byte,
1531 : loff_t length);
1532 : extern int jbd2_journal_submit_inode_data_buffers(
1533 : struct jbd2_inode *jinode);
1534 : extern int jbd2_journal_finish_inode_data_buffers(
1535 : struct jbd2_inode *jinode);
1536 : extern int jbd2_journal_begin_ordered_truncate(journal_t *journal,
1537 : struct jbd2_inode *inode, loff_t new_size);
1538 : extern void jbd2_journal_init_jbd_inode(struct jbd2_inode *jinode, struct inode *inode);
1539 : extern void jbd2_journal_release_jbd_inode(journal_t *journal, struct jbd2_inode *jinode);
1540 :
1541 : /*
1542 : * journal_head management
1543 : */
1544 : struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh);
1545 : struct journal_head *jbd2_journal_grab_journal_head(struct buffer_head *bh);
1546 : void jbd2_journal_put_journal_head(struct journal_head *jh);
1547 :
1548 : /*
1549 : * handle management
1550 : */
1551 : extern struct kmem_cache *jbd2_handle_cache;
1552 :
1553 6255 : static inline handle_t *jbd2_alloc_handle(gfp_t gfp_flags)
1554 : {
1555 6255 : return kmem_cache_zalloc(jbd2_handle_cache, gfp_flags);
1556 : }
1557 :
1558 6255 : static inline void jbd2_free_handle(handle_t *handle)
1559 : {
1560 6255 : kmem_cache_free(jbd2_handle_cache, handle);
1561 0 : }
1562 :
1563 : /*
1564 : * jbd2_inode management (optional, for those file systems that want to use
1565 : * dynamically allocated jbd2_inode structures)
1566 : */
1567 : extern struct kmem_cache *jbd2_inode_cache;
1568 :
1569 515 : static inline struct jbd2_inode *jbd2_alloc_inode(gfp_t gfp_flags)
1570 : {
1571 515 : return kmem_cache_alloc(jbd2_inode_cache, gfp_flags);
1572 : }
1573 :
1574 78 : static inline void jbd2_free_inode(struct jbd2_inode *jinode)
1575 : {
1576 78 : kmem_cache_free(jbd2_inode_cache, jinode);
1577 0 : }
1578 :
1579 : /* Primary revoke support */
1580 : #define JOURNAL_REVOKE_DEFAULT_HASH 256
1581 : extern int jbd2_journal_init_revoke(journal_t *, int);
1582 : extern void jbd2_journal_destroy_revoke_record_cache(void);
1583 : extern void jbd2_journal_destroy_revoke_table_cache(void);
1584 : extern int __init jbd2_journal_init_revoke_record_cache(void);
1585 : extern int __init jbd2_journal_init_revoke_table_cache(void);
1586 :
1587 : extern void jbd2_journal_destroy_revoke(journal_t *);
1588 : extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *);
1589 : extern int jbd2_journal_cancel_revoke(handle_t *, struct journal_head *);
1590 : extern void jbd2_journal_write_revoke_records(transaction_t *transaction,
1591 : struct list_head *log_bufs);
1592 :
1593 : /* Recovery revoke support */
1594 : extern int jbd2_journal_set_revoke(journal_t *, unsigned long long, tid_t);
1595 : extern int jbd2_journal_test_revoke(journal_t *, unsigned long long, tid_t);
1596 : extern void jbd2_journal_clear_revoke(journal_t *);
1597 : extern void jbd2_journal_switch_revoke_table(journal_t *journal);
1598 : extern void jbd2_clear_buffer_revoked_flags(journal_t *journal);
1599 :
1600 : /*
1601 : * The log thread user interface:
1602 : *
1603 : * Request space in the current transaction, and force transaction commit
1604 : * transitions on demand.
1605 : */
1606 :
1607 : int jbd2_log_start_commit(journal_t *journal, tid_t tid);
1608 : int __jbd2_log_start_commit(journal_t *journal, tid_t tid);
1609 : int jbd2_journal_start_commit(journal_t *journal, tid_t *tid);
1610 : int jbd2_log_wait_commit(journal_t *journal, tid_t tid);
1611 : int jbd2_transaction_committed(journal_t *journal, tid_t tid);
1612 : int jbd2_complete_transaction(journal_t *journal, tid_t tid);
1613 : int jbd2_log_do_checkpoint(journal_t *journal);
1614 : int jbd2_trans_will_send_data_barrier(journal_t *journal, tid_t tid);
1615 :
1616 : void __jbd2_log_wait_for_space(journal_t *journal);
1617 : extern void __jbd2_journal_drop_transaction(journal_t *, transaction_t *);
1618 : extern int jbd2_cleanup_journal_tail(journal_t *);
1619 :
1620 : /* Fast commit related APIs */
1621 : int jbd2_fc_begin_commit(journal_t *journal, tid_t tid);
1622 : int jbd2_fc_end_commit(journal_t *journal);
1623 : int jbd2_fc_end_commit_fallback(journal_t *journal);
1624 : int jbd2_fc_get_buf(journal_t *journal, struct buffer_head **bh_out);
1625 : int jbd2_submit_inode_data(struct jbd2_inode *jinode);
1626 : int jbd2_wait_inode_data(journal_t *journal, struct jbd2_inode *jinode);
1627 : int jbd2_fc_wait_bufs(journal_t *journal, int num_blks);
1628 : int jbd2_fc_release_bufs(journal_t *journal);
1629 :
1630 4 : static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal)
1631 : {
1632 4 : return (journal->j_total_len - journal->j_fc_wbufsize) / 4;
1633 : }
1634 :
1635 : /*
1636 : * is_journal_abort
1637 : *
1638 : * Simple test wrapper function to test the JBD2_ABORT state flag. This
1639 : * bit, when set, indicates that we have had a fatal error somewhere,
1640 : * either inside the journaling layer or indicated to us by the client
1641 : * (eg. ext3), and that we and should not commit any further
1642 : * transactions.
1643 : */
1644 :
1645 93323 : static inline int is_journal_aborted(journal_t *journal)
1646 : {
1647 26998 : return journal->j_flags & JBD2_ABORT;
1648 : }
1649 :
1650 66638 : static inline int is_handle_aborted(handle_t *handle)
1651 : {
1652 66638 : if (handle->h_aborted || !handle->h_transaction)
1653 : return 1;
1654 66638 : return is_journal_aborted(handle->h_transaction->t_journal);
1655 : }
1656 :
1657 0 : static inline void jbd2_journal_abort_handle(handle_t *handle)
1658 : {
1659 0 : handle->h_aborted = 1;
1660 : }
1661 :
1662 : #endif /* __KERNEL__ */
1663 :
1664 : /* Comparison functions for transaction IDs: perform comparisons using
1665 : * modulo arithmetic so that they work over sequence number wraps. */
1666 :
1667 358 : static inline int tid_gt(tid_t x, tid_t y)
1668 : {
1669 358 : int difference = (x - y);
1670 358 : return (difference > 0);
1671 : }
1672 :
1673 121 : static inline int tid_geq(tid_t x, tid_t y)
1674 : {
1675 121 : int difference = (x - y);
1676 121 : return (difference >= 0);
1677 : }
1678 :
1679 : extern int jbd2_journal_blocks_per_page(struct inode *inode);
1680 : extern size_t journal_tag_bytes(journal_t *journal);
1681 :
1682 2170 : static inline bool jbd2_journal_has_csum_v2or3_feature(journal_t *j)
1683 : {
1684 6510 : return jbd2_has_feature_csum2(j) || jbd2_has_feature_csum3(j);
1685 : }
1686 :
1687 2169 : static inline int jbd2_journal_has_csum_v2or3(journal_t *journal)
1688 : {
1689 4338 : WARN_ON_ONCE(jbd2_journal_has_csum_v2or3_feature(journal) &&
1690 : journal->j_chksum_driver == NULL);
1691 :
1692 2169 : return journal->j_chksum_driver != NULL;
1693 : }
1694 :
1695 0 : static inline int jbd2_journal_get_num_fc_blks(journal_superblock_t *jsb)
1696 : {
1697 0 : int num_fc_blocks = be32_to_cpu(jsb->s_num_fc_blks);
1698 :
1699 0 : return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS;
1700 : }
1701 :
1702 : /*
1703 : * Return number of free blocks in the log. Must be called under j_state_lock.
1704 : */
1705 6173 : static inline unsigned long jbd2_log_space_left(journal_t *journal)
1706 : {
1707 : /* Allow for rounding errors */
1708 6173 : long free = journal->j_free - 32;
1709 :
1710 6173 : if (journal->j_committing_transaction) {
1711 82 : free -= atomic_read(&journal->
1712 : j_committing_transaction->t_outstanding_credits);
1713 : }
1714 6173 : return max_t(long, free, 0);
1715 : }
1716 :
1717 : /*
1718 : * Definitions which augment the buffer_head layer
1719 : */
1720 :
1721 : /* journaling buffer types */
1722 : #define BJ_None 0 /* Not journaled */
1723 : #define BJ_Metadata 1 /* Normal journaled metadata */
1724 : #define BJ_Forget 2 /* Buffer superseded by this transaction */
1725 : #define BJ_Shadow 3 /* Buffer contents being shadowed to the log */
1726 : #define BJ_Reserved 4 /* Buffer is reserved for access by journal */
1727 : #define BJ_Types 5
1728 :
1729 : extern int jbd_blocks_per_page(struct inode *inode);
1730 :
1731 : /* JBD uses a CRC32 checksum */
1732 : #define JBD_MAX_CHECKSUM_SIZE 4
1733 :
1734 0 : static inline u32 jbd2_chksum(journal_t *journal, u32 crc,
1735 : const void *address, unsigned int length)
1736 : {
1737 0 : struct {
1738 : struct shash_desc shash;
1739 : char ctx[JBD_MAX_CHECKSUM_SIZE];
1740 : } desc;
1741 0 : int err;
1742 :
1743 0 : BUG_ON(crypto_shash_descsize(journal->j_chksum_driver) >
1744 : JBD_MAX_CHECKSUM_SIZE);
1745 :
1746 0 : desc.shash.tfm = journal->j_chksum_driver;
1747 0 : *(u32 *)desc.ctx = crc;
1748 :
1749 0 : err = crypto_shash_update(&desc.shash, address, length);
1750 0 : BUG_ON(err);
1751 :
1752 0 : return *(u32 *)desc.ctx;
1753 : }
1754 :
1755 : /* Return most recent uncommitted transaction */
1756 0 : static inline tid_t jbd2_get_latest_transaction(journal_t *journal)
1757 : {
1758 0 : tid_t tid;
1759 :
1760 0 : read_lock(&journal->j_state_lock);
1761 0 : tid = journal->j_commit_request;
1762 0 : if (journal->j_running_transaction)
1763 0 : tid = journal->j_running_transaction->t_tid;
1764 0 : read_unlock(&journal->j_state_lock);
1765 0 : return tid;
1766 : }
1767 :
1768 2395 : static inline int jbd2_handle_buffer_credits(handle_t *handle)
1769 : {
1770 2395 : journal_t *journal;
1771 :
1772 2395 : if (!handle->h_reserved)
1773 2325 : journal = handle->h_transaction->t_journal;
1774 : else
1775 70 : journal = handle->h_journal;
1776 :
1777 2395 : return handle->h_total_credits -
1778 2395 : DIV_ROUND_UP(handle->h_revoke_credits_requested,
1779 : journal->j_revoke_records_per_block);
1780 : }
1781 :
1782 : #ifdef __KERNEL__
1783 :
1784 : #define buffer_trace_init(bh) do {} while (0)
1785 : #define print_buffer_fields(bh) do {} while (0)
1786 : #define print_buffer_trace(bh) do {} while (0)
1787 : #define BUFFER_TRACE(bh, info) do {} while (0)
1788 : #define BUFFER_TRACE2(bh, bh2, info) do {} while (0)
1789 : #define JBUFFER_TRACE(jh, info) do {} while (0)
1790 :
1791 : #endif /* __KERNEL__ */
1792 :
1793 : #define EFSBADCRC EBADMSG /* Bad CRC detected */
1794 : #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
1795 :
1796 : #endif /* _LINUX_JBD2_H */
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