Root/
1 | /* |
2 | * linux/include/linux/jbd.h |
3 | * |
4 | * Written by Stephen C. Tweedie <sct@redhat.com> |
5 | * |
6 | * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved |
7 | * |
8 | * This file is part of the Linux kernel and is made available under |
9 | * the terms of the GNU General Public License, version 2, or at your |
10 | * option, any later version, incorporated herein by reference. |
11 | * |
12 | * Definitions for transaction data structures for the buffer cache |
13 | * filesystem journaling support. |
14 | */ |
15 | |
16 | #ifndef _LINUX_JBD_H |
17 | #define _LINUX_JBD_H |
18 | |
19 | /* Allow this file to be included directly into e2fsprogs */ |
20 | #ifndef __KERNEL__ |
21 | #include "jfs_compat.h" |
22 | #define JFS_DEBUG |
23 | #define jfs_debug jbd_debug |
24 | #else |
25 | |
26 | #include <linux/types.h> |
27 | #include <linux/buffer_head.h> |
28 | #include <linux/journal-head.h> |
29 | #include <linux/stddef.h> |
30 | #include <linux/bit_spinlock.h> |
31 | #include <linux/mutex.h> |
32 | #include <linux/timer.h> |
33 | #include <linux/lockdep.h> |
34 | #include <linux/slab.h> |
35 | |
36 | #define journal_oom_retry 1 |
37 | |
38 | /* |
39 | * Define JBD_PARANOID_IOFAIL to cause a kernel BUG() if ext3 finds |
40 | * certain classes of error which can occur due to failed IOs. Under |
41 | * normal use we want ext3 to continue after such errors, because |
42 | * hardware _can_ fail, but for debugging purposes when running tests on |
43 | * known-good hardware we may want to trap these errors. |
44 | */ |
45 | #undef JBD_PARANOID_IOFAIL |
46 | |
47 | /* |
48 | * The default maximum commit age, in seconds. |
49 | */ |
50 | #define JBD_DEFAULT_MAX_COMMIT_AGE 5 |
51 | |
52 | #ifdef CONFIG_JBD_DEBUG |
53 | /* |
54 | * Define JBD_EXPENSIVE_CHECKING to enable more expensive internal |
55 | * consistency checks. By default we don't do this unless |
56 | * CONFIG_JBD_DEBUG is on. |
57 | */ |
58 | #define JBD_EXPENSIVE_CHECKING |
59 | extern u8 journal_enable_debug; |
60 | |
61 | #define jbd_debug(n, f, a...) \ |
62 | do { \ |
63 | if ((n) <= journal_enable_debug) { \ |
64 | printk (KERN_DEBUG "(%s, %d): %s: ", \ |
65 | __FILE__, __LINE__, __func__); \ |
66 | printk (f, ## a); \ |
67 | } \ |
68 | } while (0) |
69 | #else |
70 | #define jbd_debug(f, a...) /**/ |
71 | #endif |
72 | |
73 | static inline void *jbd_alloc(size_t size, gfp_t flags) |
74 | { |
75 | return (void *)__get_free_pages(flags, get_order(size)); |
76 | } |
77 | |
78 | static inline void jbd_free(void *ptr, size_t size) |
79 | { |
80 | free_pages((unsigned long)ptr, get_order(size)); |
81 | }; |
82 | |
83 | #define JFS_MIN_JOURNAL_BLOCKS 1024 |
84 | |
85 | |
86 | /** |
87 | * typedef handle_t - The handle_t type represents a single atomic update being performed by some process. |
88 | * |
89 | * All filesystem modifications made by the process go |
90 | * through this handle. Recursive operations (such as quota operations) |
91 | * are gathered into a single update. |
92 | * |
93 | * The buffer credits field is used to account for journaled buffers |
94 | * being modified by the running process. To ensure that there is |
95 | * enough log space for all outstanding operations, we need to limit the |
96 | * number of outstanding buffers possible at any time. When the |
97 | * operation completes, any buffer credits not used are credited back to |
98 | * the transaction, so that at all times we know how many buffers the |
99 | * outstanding updates on a transaction might possibly touch. |
100 | * |
101 | * This is an opaque datatype. |
102 | **/ |
103 | typedef struct handle_s handle_t; /* Atomic operation type */ |
104 | |
105 | |
106 | /** |
107 | * typedef journal_t - The journal_t maintains all of the journaling state information for a single filesystem. |
108 | * |
109 | * journal_t is linked to from the fs superblock structure. |
110 | * |
111 | * We use the journal_t to keep track of all outstanding transaction |
112 | * activity on the filesystem, and to manage the state of the log |
113 | * writing process. |
114 | * |
115 | * This is an opaque datatype. |
116 | **/ |
117 | typedef struct journal_s journal_t; /* Journal control structure */ |
118 | #endif |
119 | |
120 | /* |
121 | * Internal structures used by the logging mechanism: |
122 | */ |
123 | |
124 | #define JFS_MAGIC_NUMBER 0xc03b3998U /* The first 4 bytes of /dev/random! */ |
125 | |
126 | /* |
127 | * On-disk structures |
128 | */ |
129 | |
130 | /* |
131 | * Descriptor block types: |
132 | */ |
133 | |
134 | #define JFS_DESCRIPTOR_BLOCK 1 |
135 | #define JFS_COMMIT_BLOCK 2 |
136 | #define JFS_SUPERBLOCK_V1 3 |
137 | #define JFS_SUPERBLOCK_V2 4 |
138 | #define JFS_REVOKE_BLOCK 5 |
139 | |
140 | /* |
141 | * Standard header for all descriptor blocks: |
142 | */ |
143 | typedef struct journal_header_s |
144 | { |
145 | __be32 h_magic; |
146 | __be32 h_blocktype; |
147 | __be32 h_sequence; |
148 | } journal_header_t; |
149 | |
150 | |
151 | /* |
152 | * The block tag: used to describe a single buffer in the journal |
153 | */ |
154 | typedef struct journal_block_tag_s |
155 | { |
156 | __be32 t_blocknr; /* The on-disk block number */ |
157 | __be32 t_flags; /* See below */ |
158 | } journal_block_tag_t; |
159 | |
160 | /* |
161 | * The revoke descriptor: used on disk to describe a series of blocks to |
162 | * be revoked from the log |
163 | */ |
164 | typedef struct journal_revoke_header_s |
165 | { |
166 | journal_header_t r_header; |
167 | __be32 r_count; /* Count of bytes used in the block */ |
168 | } journal_revoke_header_t; |
169 | |
170 | |
171 | /* Definitions for the journal tag flags word: */ |
172 | #define JFS_FLAG_ESCAPE 1 /* on-disk block is escaped */ |
173 | #define JFS_FLAG_SAME_UUID 2 /* block has same uuid as previous */ |
174 | #define JFS_FLAG_DELETED 4 /* block deleted by this transaction */ |
175 | #define JFS_FLAG_LAST_TAG 8 /* last tag in this descriptor block */ |
176 | |
177 | |
178 | /* |
179 | * The journal superblock. All fields are in big-endian byte order. |
180 | */ |
181 | typedef struct journal_superblock_s |
182 | { |
183 | /* 0x0000 */ |
184 | journal_header_t s_header; |
185 | |
186 | /* 0x000C */ |
187 | /* Static information describing the journal */ |
188 | __be32 s_blocksize; /* journal device blocksize */ |
189 | __be32 s_maxlen; /* total blocks in journal file */ |
190 | __be32 s_first; /* first block of log information */ |
191 | |
192 | /* 0x0018 */ |
193 | /* Dynamic information describing the current state of the log */ |
194 | __be32 s_sequence; /* first commit ID expected in log */ |
195 | __be32 s_start; /* blocknr of start of log */ |
196 | |
197 | /* 0x0020 */ |
198 | /* Error value, as set by journal_abort(). */ |
199 | __be32 s_errno; |
200 | |
201 | /* 0x0024 */ |
202 | /* Remaining fields are only valid in a version-2 superblock */ |
203 | __be32 s_feature_compat; /* compatible feature set */ |
204 | __be32 s_feature_incompat; /* incompatible feature set */ |
205 | __be32 s_feature_ro_compat; /* readonly-compatible feature set */ |
206 | /* 0x0030 */ |
207 | __u8 s_uuid[16]; /* 128-bit uuid for journal */ |
208 | |
209 | /* 0x0040 */ |
210 | __be32 s_nr_users; /* Nr of filesystems sharing log */ |
211 | |
212 | __be32 s_dynsuper; /* Blocknr of dynamic superblock copy*/ |
213 | |
214 | /* 0x0048 */ |
215 | __be32 s_max_transaction; /* Limit of journal blocks per trans.*/ |
216 | __be32 s_max_trans_data; /* Limit of data blocks per trans. */ |
217 | |
218 | /* 0x0050 */ |
219 | __u32 s_padding[44]; |
220 | |
221 | /* 0x0100 */ |
222 | __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ |
223 | /* 0x0400 */ |
224 | } journal_superblock_t; |
225 | |
226 | #define JFS_HAS_COMPAT_FEATURE(j,mask) \ |
227 | ((j)->j_format_version >= 2 && \ |
228 | ((j)->j_superblock->s_feature_compat & cpu_to_be32((mask)))) |
229 | #define JFS_HAS_RO_COMPAT_FEATURE(j,mask) \ |
230 | ((j)->j_format_version >= 2 && \ |
231 | ((j)->j_superblock->s_feature_ro_compat & cpu_to_be32((mask)))) |
232 | #define JFS_HAS_INCOMPAT_FEATURE(j,mask) \ |
233 | ((j)->j_format_version >= 2 && \ |
234 | ((j)->j_superblock->s_feature_incompat & cpu_to_be32((mask)))) |
235 | |
236 | #define JFS_FEATURE_INCOMPAT_REVOKE 0x00000001 |
237 | |
238 | /* Features known to this kernel version: */ |
239 | #define JFS_KNOWN_COMPAT_FEATURES 0 |
240 | #define JFS_KNOWN_ROCOMPAT_FEATURES 0 |
241 | #define JFS_KNOWN_INCOMPAT_FEATURES JFS_FEATURE_INCOMPAT_REVOKE |
242 | |
243 | #ifdef __KERNEL__ |
244 | |
245 | #include <linux/fs.h> |
246 | #include <linux/sched.h> |
247 | #include <linux/jbd_common.h> |
248 | |
249 | #define J_ASSERT(assert) BUG_ON(!(assert)) |
250 | |
251 | #define J_ASSERT_BH(bh, expr) J_ASSERT(expr) |
252 | #define J_ASSERT_JH(jh, expr) J_ASSERT(expr) |
253 | |
254 | #if defined(JBD_PARANOID_IOFAIL) |
255 | #define J_EXPECT(expr, why...) J_ASSERT(expr) |
256 | #define J_EXPECT_BH(bh, expr, why...) J_ASSERT_BH(bh, expr) |
257 | #define J_EXPECT_JH(jh, expr, why...) J_ASSERT_JH(jh, expr) |
258 | #else |
259 | #define __journal_expect(expr, why...) \ |
260 | ({ \ |
261 | int val = (expr); \ |
262 | if (!val) { \ |
263 | printk(KERN_ERR \ |
264 | "EXT3-fs unexpected failure: %s;\n",# expr); \ |
265 | printk(KERN_ERR why "\n"); \ |
266 | } \ |
267 | val; \ |
268 | }) |
269 | #define J_EXPECT(expr, why...) __journal_expect(expr, ## why) |
270 | #define J_EXPECT_BH(bh, expr, why...) __journal_expect(expr, ## why) |
271 | #define J_EXPECT_JH(jh, expr, why...) __journal_expect(expr, ## why) |
272 | #endif |
273 | |
274 | struct jbd_revoke_table_s; |
275 | |
276 | /** |
277 | * struct handle_s - this is the concrete type associated with handle_t. |
278 | * @h_transaction: Which compound transaction is this update a part of? |
279 | * @h_buffer_credits: Number of remaining buffers we are allowed to dirty. |
280 | * @h_ref: Reference count on this handle |
281 | * @h_err: Field for caller's use to track errors through large fs operations |
282 | * @h_sync: flag for sync-on-close |
283 | * @h_jdata: flag to force data journaling |
284 | * @h_aborted: flag indicating fatal error on handle |
285 | * @h_lockdep_map: lockdep info for debugging lock problems |
286 | */ |
287 | struct handle_s |
288 | { |
289 | /* Which compound transaction is this update a part of? */ |
290 | transaction_t *h_transaction; |
291 | |
292 | /* Number of remaining buffers we are allowed to dirty: */ |
293 | int h_buffer_credits; |
294 | |
295 | /* Reference count on this handle */ |
296 | int h_ref; |
297 | |
298 | /* Field for caller's use to track errors through large fs */ |
299 | /* operations */ |
300 | int h_err; |
301 | |
302 | /* Flags [no locking] */ |
303 | unsigned int h_sync: 1; /* sync-on-close */ |
304 | unsigned int h_jdata: 1; /* force data journaling */ |
305 | unsigned int h_aborted: 1; /* fatal error on handle */ |
306 | |
307 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
308 | struct lockdep_map h_lockdep_map; |
309 | #endif |
310 | }; |
311 | |
312 | |
313 | /* The transaction_t type is the guts of the journaling mechanism. It |
314 | * tracks a compound transaction through its various states: |
315 | * |
316 | * RUNNING: accepting new updates |
317 | * LOCKED: Updates still running but we don't accept new ones |
318 | * RUNDOWN: Updates are tidying up but have finished requesting |
319 | * new buffers to modify (state not used for now) |
320 | * FLUSH: All updates complete, but we are still writing to disk |
321 | * COMMIT: All data on disk, writing commit record |
322 | * FINISHED: We still have to keep the transaction for checkpointing. |
323 | * |
324 | * The transaction keeps track of all of the buffers modified by a |
325 | * running transaction, and all of the buffers committed but not yet |
326 | * flushed to home for finished transactions. |
327 | */ |
328 | |
329 | /* |
330 | * Lock ranking: |
331 | * |
332 | * j_list_lock |
333 | * ->jbd_lock_bh_journal_head() (This is "innermost") |
334 | * |
335 | * j_state_lock |
336 | * ->jbd_lock_bh_state() |
337 | * |
338 | * jbd_lock_bh_state() |
339 | * ->j_list_lock |
340 | * |
341 | * j_state_lock |
342 | * ->t_handle_lock |
343 | * |
344 | * j_state_lock |
345 | * ->j_list_lock (journal_unmap_buffer) |
346 | * |
347 | */ |
348 | |
349 | struct transaction_s |
350 | { |
351 | /* Pointer to the journal for this transaction. [no locking] */ |
352 | journal_t *t_journal; |
353 | |
354 | /* Sequence number for this transaction [no locking] */ |
355 | tid_t t_tid; |
356 | |
357 | /* |
358 | * Transaction's current state |
359 | * [no locking - only kjournald alters this] |
360 | * [j_list_lock] guards transition of a transaction into T_FINISHED |
361 | * state and subsequent call of __journal_drop_transaction() |
362 | * FIXME: needs barriers |
363 | * KLUDGE: [use j_state_lock] |
364 | */ |
365 | enum { |
366 | T_RUNNING, |
367 | T_LOCKED, |
368 | T_FLUSH, |
369 | T_COMMIT, |
370 | T_COMMIT_RECORD, |
371 | T_FINISHED |
372 | } t_state; |
373 | |
374 | /* |
375 | * Where in the log does this transaction's commit start? [no locking] |
376 | */ |
377 | unsigned int t_log_start; |
378 | |
379 | /* Number of buffers on the t_buffers list [j_list_lock] */ |
380 | int t_nr_buffers; |
381 | |
382 | /* |
383 | * Doubly-linked circular list of all buffers reserved but not yet |
384 | * modified by this transaction [j_list_lock] |
385 | */ |
386 | struct journal_head *t_reserved_list; |
387 | |
388 | /* |
389 | * Doubly-linked circular list of all buffers under writeout during |
390 | * commit [j_list_lock] |
391 | */ |
392 | struct journal_head *t_locked_list; |
393 | |
394 | /* |
395 | * Doubly-linked circular list of all metadata buffers owned by this |
396 | * transaction [j_list_lock] |
397 | */ |
398 | struct journal_head *t_buffers; |
399 | |
400 | /* |
401 | * Doubly-linked circular list of all data buffers still to be |
402 | * flushed before this transaction can be committed [j_list_lock] |
403 | */ |
404 | struct journal_head *t_sync_datalist; |
405 | |
406 | /* |
407 | * Doubly-linked circular list of all forget buffers (superseded |
408 | * buffers which we can un-checkpoint once this transaction commits) |
409 | * [j_list_lock] |
410 | */ |
411 | struct journal_head *t_forget; |
412 | |
413 | /* |
414 | * Doubly-linked circular list of all buffers still to be flushed before |
415 | * this transaction can be checkpointed. [j_list_lock] |
416 | */ |
417 | struct journal_head *t_checkpoint_list; |
418 | |
419 | /* |
420 | * Doubly-linked circular list of all buffers submitted for IO while |
421 | * checkpointing. [j_list_lock] |
422 | */ |
423 | struct journal_head *t_checkpoint_io_list; |
424 | |
425 | /* |
426 | * Doubly-linked circular list of temporary buffers currently undergoing |
427 | * IO in the log [j_list_lock] |
428 | */ |
429 | struct journal_head *t_iobuf_list; |
430 | |
431 | /* |
432 | * Doubly-linked circular list of metadata buffers being shadowed by log |
433 | * IO. The IO buffers on the iobuf list and the shadow buffers on this |
434 | * list match each other one for one at all times. [j_list_lock] |
435 | */ |
436 | struct journal_head *t_shadow_list; |
437 | |
438 | /* |
439 | * Doubly-linked circular list of control buffers being written to the |
440 | * log. [j_list_lock] |
441 | */ |
442 | struct journal_head *t_log_list; |
443 | |
444 | /* |
445 | * Protects info related to handles |
446 | */ |
447 | spinlock_t t_handle_lock; |
448 | |
449 | /* |
450 | * Number of outstanding updates running on this transaction |
451 | * [t_handle_lock] |
452 | */ |
453 | int t_updates; |
454 | |
455 | /* |
456 | * Number of buffers reserved for use by all handles in this transaction |
457 | * handle but not yet modified. [t_handle_lock] |
458 | */ |
459 | int t_outstanding_credits; |
460 | |
461 | /* |
462 | * Forward and backward links for the circular list of all transactions |
463 | * awaiting checkpoint. [j_list_lock] |
464 | */ |
465 | transaction_t *t_cpnext, *t_cpprev; |
466 | |
467 | /* |
468 | * When will the transaction expire (become due for commit), in jiffies? |
469 | * [no locking] |
470 | */ |
471 | unsigned long t_expires; |
472 | |
473 | /* |
474 | * When this transaction started, in nanoseconds [no locking] |
475 | */ |
476 | ktime_t t_start_time; |
477 | |
478 | /* |
479 | * How many handles used this transaction? [t_handle_lock] |
480 | */ |
481 | int t_handle_count; |
482 | }; |
483 | |
484 | /** |
485 | * struct journal_s - this is the concrete type associated with journal_t. |
486 | * @j_flags: General journaling state flags |
487 | * @j_errno: Is there an outstanding uncleared error on the journal (from a |
488 | * prior abort)? |
489 | * @j_sb_buffer: First part of superblock buffer |
490 | * @j_superblock: Second part of superblock buffer |
491 | * @j_format_version: Version of the superblock format |
492 | * @j_state_lock: Protect the various scalars in the journal |
493 | * @j_barrier_count: Number of processes waiting to create a barrier lock |
494 | * @j_running_transaction: The current running transaction.. |
495 | * @j_committing_transaction: the transaction we are pushing to disk |
496 | * @j_checkpoint_transactions: a linked circular list of all transactions |
497 | * waiting for checkpointing |
498 | * @j_wait_transaction_locked: Wait queue for waiting for a locked transaction |
499 | * to start committing, or for a barrier lock to be released |
500 | * @j_wait_logspace: Wait queue for waiting for checkpointing to complete |
501 | * @j_wait_done_commit: Wait queue for waiting for commit to complete |
502 | * @j_wait_checkpoint: Wait queue to trigger checkpointing |
503 | * @j_wait_commit: Wait queue to trigger commit |
504 | * @j_wait_updates: Wait queue to wait for updates to complete |
505 | * @j_checkpoint_mutex: Mutex for locking against concurrent checkpoints |
506 | * @j_head: Journal head - identifies the first unused block in the journal |
507 | * @j_tail: Journal tail - identifies the oldest still-used block in the |
508 | * journal. |
509 | * @j_free: Journal free - how many free blocks are there in the journal? |
510 | * @j_first: The block number of the first usable block |
511 | * @j_last: The block number one beyond the last usable block |
512 | * @j_dev: Device where we store the journal |
513 | * @j_blocksize: blocksize for the location where we store the journal. |
514 | * @j_blk_offset: starting block offset for into the device where we store the |
515 | * journal |
516 | * @j_fs_dev: Device which holds the client fs. For internal journal this will |
517 | * be equal to j_dev |
518 | * @j_maxlen: Total maximum capacity of the journal region on disk. |
519 | * @j_list_lock: Protects the buffer lists and internal buffer state. |
520 | * @j_inode: Optional inode where we store the journal. If present, all journal |
521 | * block numbers are mapped into this inode via bmap(). |
522 | * @j_tail_sequence: Sequence number of the oldest transaction in the log |
523 | * @j_transaction_sequence: Sequence number of the next transaction to grant |
524 | * @j_commit_sequence: Sequence number of the most recently committed |
525 | * transaction |
526 | * @j_commit_request: Sequence number of the most recent transaction wanting |
527 | * commit |
528 | * @j_commit_waited: Sequence number of the most recent transaction someone |
529 | * is waiting for to commit. |
530 | * @j_uuid: Uuid of client object. |
531 | * @j_task: Pointer to the current commit thread for this journal |
532 | * @j_max_transaction_buffers: Maximum number of metadata buffers to allow in a |
533 | * single compound commit transaction |
534 | * @j_commit_interval: What is the maximum transaction lifetime before we begin |
535 | * a commit? |
536 | * @j_commit_timer: The timer used to wakeup the commit thread |
537 | * @j_revoke_lock: Protect the revoke table |
538 | * @j_revoke: The revoke table - maintains the list of revoked blocks in the |
539 | * current transaction. |
540 | * @j_revoke_table: alternate revoke tables for j_revoke |
541 | * @j_wbuf: array of buffer_heads for journal_commit_transaction |
542 | * @j_wbufsize: maximum number of buffer_heads allowed in j_wbuf, the |
543 | * number that will fit in j_blocksize |
544 | * @j_last_sync_writer: most recent pid which did a synchronous write |
545 | * @j_average_commit_time: the average amount of time in nanoseconds it |
546 | * takes to commit a transaction to the disk. |
547 | * @j_private: An opaque pointer to fs-private information. |
548 | */ |
549 | |
550 | struct journal_s |
551 | { |
552 | /* General journaling state flags [j_state_lock] */ |
553 | unsigned long j_flags; |
554 | |
555 | /* |
556 | * Is there an outstanding uncleared error on the journal (from a prior |
557 | * abort)? [j_state_lock] |
558 | */ |
559 | int j_errno; |
560 | |
561 | /* The superblock buffer */ |
562 | struct buffer_head *j_sb_buffer; |
563 | journal_superblock_t *j_superblock; |
564 | |
565 | /* Version of the superblock format */ |
566 | int j_format_version; |
567 | |
568 | /* |
569 | * Protect the various scalars in the journal |
570 | */ |
571 | spinlock_t j_state_lock; |
572 | |
573 | /* |
574 | * Number of processes waiting to create a barrier lock [j_state_lock] |
575 | */ |
576 | int j_barrier_count; |
577 | |
578 | /* |
579 | * Transactions: The current running transaction... |
580 | * [j_state_lock] [caller holding open handle] |
581 | */ |
582 | transaction_t *j_running_transaction; |
583 | |
584 | /* |
585 | * the transaction we are pushing to disk |
586 | * [j_state_lock] [caller holding open handle] |
587 | */ |
588 | transaction_t *j_committing_transaction; |
589 | |
590 | /* |
591 | * ... and a linked circular list of all transactions waiting for |
592 | * checkpointing. [j_list_lock] |
593 | */ |
594 | transaction_t *j_checkpoint_transactions; |
595 | |
596 | /* |
597 | * Wait queue for waiting for a locked transaction to start committing, |
598 | * or for a barrier lock to be released |
599 | */ |
600 | wait_queue_head_t j_wait_transaction_locked; |
601 | |
602 | /* Wait queue for waiting for checkpointing to complete */ |
603 | wait_queue_head_t j_wait_logspace; |
604 | |
605 | /* Wait queue for waiting for commit to complete */ |
606 | wait_queue_head_t j_wait_done_commit; |
607 | |
608 | /* Wait queue to trigger checkpointing */ |
609 | wait_queue_head_t j_wait_checkpoint; |
610 | |
611 | /* Wait queue to trigger commit */ |
612 | wait_queue_head_t j_wait_commit; |
613 | |
614 | /* Wait queue to wait for updates to complete */ |
615 | wait_queue_head_t j_wait_updates; |
616 | |
617 | /* Semaphore for locking against concurrent checkpoints */ |
618 | struct mutex j_checkpoint_mutex; |
619 | |
620 | /* |
621 | * Journal head: identifies the first unused block in the journal. |
622 | * [j_state_lock] |
623 | */ |
624 | unsigned int j_head; |
625 | |
626 | /* |
627 | * Journal tail: identifies the oldest still-used block in the journal. |
628 | * [j_state_lock] |
629 | */ |
630 | unsigned int j_tail; |
631 | |
632 | /* |
633 | * Journal free: how many free blocks are there in the journal? |
634 | * [j_state_lock] |
635 | */ |
636 | unsigned int j_free; |
637 | |
638 | /* |
639 | * Journal start and end: the block numbers of the first usable block |
640 | * and one beyond the last usable block in the journal. [j_state_lock] |
641 | */ |
642 | unsigned int j_first; |
643 | unsigned int j_last; |
644 | |
645 | /* |
646 | * Device, blocksize and starting block offset for the location where we |
647 | * store the journal. |
648 | */ |
649 | struct block_device *j_dev; |
650 | int j_blocksize; |
651 | unsigned int j_blk_offset; |
652 | |
653 | /* |
654 | * Device which holds the client fs. For internal journal this will be |
655 | * equal to j_dev. |
656 | */ |
657 | struct block_device *j_fs_dev; |
658 | |
659 | /* Total maximum capacity of the journal region on disk. */ |
660 | unsigned int j_maxlen; |
661 | |
662 | /* |
663 | * Protects the buffer lists and internal buffer state. |
664 | */ |
665 | spinlock_t j_list_lock; |
666 | |
667 | /* Optional inode where we store the journal. If present, all */ |
668 | /* journal block numbers are mapped into this inode via */ |
669 | /* bmap(). */ |
670 | struct inode *j_inode; |
671 | |
672 | /* |
673 | * Sequence number of the oldest transaction in the log [j_state_lock] |
674 | */ |
675 | tid_t j_tail_sequence; |
676 | |
677 | /* |
678 | * Sequence number of the next transaction to grant [j_state_lock] |
679 | */ |
680 | tid_t j_transaction_sequence; |
681 | |
682 | /* |
683 | * Sequence number of the most recently committed transaction |
684 | * [j_state_lock]. |
685 | */ |
686 | tid_t j_commit_sequence; |
687 | |
688 | /* |
689 | * Sequence number of the most recent transaction wanting commit |
690 | * [j_state_lock] |
691 | */ |
692 | tid_t j_commit_request; |
693 | |
694 | /* |
695 | * Sequence number of the most recent transaction someone is waiting |
696 | * for to commit. |
697 | * [j_state_lock] |
698 | */ |
699 | tid_t j_commit_waited; |
700 | |
701 | /* |
702 | * Journal uuid: identifies the object (filesystem, LVM volume etc) |
703 | * backed by this journal. This will eventually be replaced by an array |
704 | * of uuids, allowing us to index multiple devices within a single |
705 | * journal and to perform atomic updates across them. |
706 | */ |
707 | __u8 j_uuid[16]; |
708 | |
709 | /* Pointer to the current commit thread for this journal */ |
710 | struct task_struct *j_task; |
711 | |
712 | /* |
713 | * Maximum number of metadata buffers to allow in a single compound |
714 | * commit transaction |
715 | */ |
716 | int j_max_transaction_buffers; |
717 | |
718 | /* |
719 | * What is the maximum transaction lifetime before we begin a commit? |
720 | */ |
721 | unsigned long j_commit_interval; |
722 | |
723 | /* The timer used to wakeup the commit thread: */ |
724 | struct timer_list j_commit_timer; |
725 | |
726 | /* |
727 | * The revoke table: maintains the list of revoked blocks in the |
728 | * current transaction. [j_revoke_lock] |
729 | */ |
730 | spinlock_t j_revoke_lock; |
731 | struct jbd_revoke_table_s *j_revoke; |
732 | struct jbd_revoke_table_s *j_revoke_table[2]; |
733 | |
734 | /* |
735 | * array of bhs for journal_commit_transaction |
736 | */ |
737 | struct buffer_head **j_wbuf; |
738 | int j_wbufsize; |
739 | |
740 | /* |
741 | * this is the pid of the last person to run a synchronous operation |
742 | * through the journal. |
743 | */ |
744 | pid_t j_last_sync_writer; |
745 | |
746 | /* |
747 | * the average amount of time in nanoseconds it takes to commit a |
748 | * transaction to the disk. [j_state_lock] |
749 | */ |
750 | u64 j_average_commit_time; |
751 | |
752 | /* |
753 | * An opaque pointer to fs-private information. ext3 puts its |
754 | * superblock pointer here |
755 | */ |
756 | void *j_private; |
757 | }; |
758 | |
759 | /* |
760 | * Journal flag definitions |
761 | */ |
762 | #define JFS_UNMOUNT 0x001 /* Journal thread is being destroyed */ |
763 | #define JFS_ABORT 0x002 /* Journaling has been aborted for errors. */ |
764 | #define JFS_ACK_ERR 0x004 /* The errno in the sb has been acked */ |
765 | #define JFS_FLUSHED 0x008 /* The journal superblock has been flushed */ |
766 | #define JFS_LOADED 0x010 /* The journal superblock has been loaded */ |
767 | #define JFS_BARRIER 0x020 /* Use IDE barriers */ |
768 | #define JFS_ABORT_ON_SYNCDATA_ERR 0x040 /* Abort the journal on file |
769 | * data write error in ordered |
770 | * mode */ |
771 | |
772 | /* |
773 | * Function declarations for the journaling transaction and buffer |
774 | * management |
775 | */ |
776 | |
777 | /* Filing buffers */ |
778 | extern void journal_unfile_buffer(journal_t *, struct journal_head *); |
779 | extern void __journal_unfile_buffer(struct journal_head *); |
780 | extern void __journal_refile_buffer(struct journal_head *); |
781 | extern void journal_refile_buffer(journal_t *, struct journal_head *); |
782 | extern void __journal_file_buffer(struct journal_head *, transaction_t *, int); |
783 | extern void __journal_free_buffer(struct journal_head *bh); |
784 | extern void journal_file_buffer(struct journal_head *, transaction_t *, int); |
785 | extern void __journal_clean_data_list(transaction_t *transaction); |
786 | |
787 | /* Log buffer allocation */ |
788 | extern struct journal_head * journal_get_descriptor_buffer(journal_t *); |
789 | int journal_next_log_block(journal_t *, unsigned int *); |
790 | |
791 | /* Commit management */ |
792 | extern void journal_commit_transaction(journal_t *); |
793 | |
794 | /* Checkpoint list management */ |
795 | int __journal_clean_checkpoint_list(journal_t *journal); |
796 | int __journal_remove_checkpoint(struct journal_head *); |
797 | void __journal_insert_checkpoint(struct journal_head *, transaction_t *); |
798 | |
799 | /* Buffer IO */ |
800 | extern int |
801 | journal_write_metadata_buffer(transaction_t *transaction, |
802 | struct journal_head *jh_in, |
803 | struct journal_head **jh_out, |
804 | unsigned int blocknr); |
805 | |
806 | /* Transaction locking */ |
807 | extern void __wait_on_journal (journal_t *); |
808 | |
809 | /* |
810 | * Journal locking. |
811 | * |
812 | * We need to lock the journal during transaction state changes so that nobody |
813 | * ever tries to take a handle on the running transaction while we are in the |
814 | * middle of moving it to the commit phase. j_state_lock does this. |
815 | * |
816 | * Note that the locking is completely interrupt unsafe. We never touch |
817 | * journal structures from interrupts. |
818 | */ |
819 | |
820 | static inline handle_t *journal_current_handle(void) |
821 | { |
822 | return current->journal_info; |
823 | } |
824 | |
825 | /* The journaling code user interface: |
826 | * |
827 | * Create and destroy handles |
828 | * Register buffer modifications against the current transaction. |
829 | */ |
830 | |
831 | extern handle_t *journal_start(journal_t *, int nblocks); |
832 | extern int journal_restart (handle_t *, int nblocks); |
833 | extern int journal_extend (handle_t *, int nblocks); |
834 | extern int journal_get_write_access(handle_t *, struct buffer_head *); |
835 | extern int journal_get_create_access (handle_t *, struct buffer_head *); |
836 | extern int journal_get_undo_access(handle_t *, struct buffer_head *); |
837 | extern int journal_dirty_data (handle_t *, struct buffer_head *); |
838 | extern int journal_dirty_metadata (handle_t *, struct buffer_head *); |
839 | extern void journal_release_buffer (handle_t *, struct buffer_head *); |
840 | extern int journal_forget (handle_t *, struct buffer_head *); |
841 | extern void journal_sync_buffer (struct buffer_head *); |
842 | extern void journal_invalidatepage(journal_t *, |
843 | struct page *, unsigned long); |
844 | extern int journal_try_to_free_buffers(journal_t *, struct page *, gfp_t); |
845 | extern int journal_stop(handle_t *); |
846 | extern int journal_flush (journal_t *); |
847 | extern void journal_lock_updates (journal_t *); |
848 | extern void journal_unlock_updates (journal_t *); |
849 | |
850 | extern journal_t * journal_init_dev(struct block_device *bdev, |
851 | struct block_device *fs_dev, |
852 | int start, int len, int bsize); |
853 | extern journal_t * journal_init_inode (struct inode *); |
854 | extern int journal_update_format (journal_t *); |
855 | extern int journal_check_used_features |
856 | (journal_t *, unsigned long, unsigned long, unsigned long); |
857 | extern int journal_check_available_features |
858 | (journal_t *, unsigned long, unsigned long, unsigned long); |
859 | extern int journal_set_features |
860 | (journal_t *, unsigned long, unsigned long, unsigned long); |
861 | extern int journal_create (journal_t *); |
862 | extern int journal_load (journal_t *journal); |
863 | extern int journal_destroy (journal_t *); |
864 | extern int journal_recover (journal_t *journal); |
865 | extern int journal_wipe (journal_t *, int); |
866 | extern int journal_skip_recovery (journal_t *); |
867 | extern void journal_update_sb_log_tail (journal_t *, tid_t, unsigned int, |
868 | int); |
869 | extern void journal_abort (journal_t *, int); |
870 | extern int journal_errno (journal_t *); |
871 | extern void journal_ack_err (journal_t *); |
872 | extern int journal_clear_err (journal_t *); |
873 | extern int journal_bmap(journal_t *, unsigned int, unsigned int *); |
874 | extern int journal_force_commit(journal_t *); |
875 | |
876 | /* |
877 | * journal_head management |
878 | */ |
879 | struct journal_head *journal_add_journal_head(struct buffer_head *bh); |
880 | struct journal_head *journal_grab_journal_head(struct buffer_head *bh); |
881 | void journal_put_journal_head(struct journal_head *jh); |
882 | |
883 | /* |
884 | * handle management |
885 | */ |
886 | extern struct kmem_cache *jbd_handle_cache; |
887 | |
888 | static inline handle_t *jbd_alloc_handle(gfp_t gfp_flags) |
889 | { |
890 | return kmem_cache_alloc(jbd_handle_cache, gfp_flags); |
891 | } |
892 | |
893 | static inline void jbd_free_handle(handle_t *handle) |
894 | { |
895 | kmem_cache_free(jbd_handle_cache, handle); |
896 | } |
897 | |
898 | /* Primary revoke support */ |
899 | #define JOURNAL_REVOKE_DEFAULT_HASH 256 |
900 | extern int journal_init_revoke(journal_t *, int); |
901 | extern void journal_destroy_revoke_caches(void); |
902 | extern int journal_init_revoke_caches(void); |
903 | |
904 | extern void journal_destroy_revoke(journal_t *); |
905 | extern int journal_revoke (handle_t *, |
906 | unsigned int, struct buffer_head *); |
907 | extern int journal_cancel_revoke(handle_t *, struct journal_head *); |
908 | extern void journal_write_revoke_records(journal_t *, |
909 | transaction_t *, int); |
910 | |
911 | /* Recovery revoke support */ |
912 | extern int journal_set_revoke(journal_t *, unsigned int, tid_t); |
913 | extern int journal_test_revoke(journal_t *, unsigned int, tid_t); |
914 | extern void journal_clear_revoke(journal_t *); |
915 | extern void journal_switch_revoke_table(journal_t *journal); |
916 | extern void journal_clear_buffer_revoked_flags(journal_t *journal); |
917 | |
918 | /* |
919 | * The log thread user interface: |
920 | * |
921 | * Request space in the current transaction, and force transaction commit |
922 | * transitions on demand. |
923 | */ |
924 | |
925 | int __log_space_left(journal_t *); /* Called with journal locked */ |
926 | int log_start_commit(journal_t *journal, tid_t tid); |
927 | int __log_start_commit(journal_t *journal, tid_t tid); |
928 | int journal_start_commit(journal_t *journal, tid_t *tid); |
929 | int journal_force_commit_nested(journal_t *journal); |
930 | int log_wait_commit(journal_t *journal, tid_t tid); |
931 | int log_do_checkpoint(journal_t *journal); |
932 | int journal_trans_will_send_data_barrier(journal_t *journal, tid_t tid); |
933 | |
934 | void __log_wait_for_space(journal_t *journal); |
935 | extern void __journal_drop_transaction(journal_t *, transaction_t *); |
936 | extern int cleanup_journal_tail(journal_t *); |
937 | |
938 | /* Debugging code only: */ |
939 | |
940 | #define jbd_ENOSYS() \ |
941 | do { \ |
942 | printk (KERN_ERR "JBD unimplemented function %s\n", __func__); \ |
943 | current->state = TASK_UNINTERRUPTIBLE; \ |
944 | schedule(); \ |
945 | } while (1) |
946 | |
947 | /* |
948 | * is_journal_abort |
949 | * |
950 | * Simple test wrapper function to test the JFS_ABORT state flag. This |
951 | * bit, when set, indicates that we have had a fatal error somewhere, |
952 | * either inside the journaling layer or indicated to us by the client |
953 | * (eg. ext3), and that we and should not commit any further |
954 | * transactions. |
955 | */ |
956 | |
957 | static inline int is_journal_aborted(journal_t *journal) |
958 | { |
959 | return journal->j_flags & JFS_ABORT; |
960 | } |
961 | |
962 | static inline int is_handle_aborted(handle_t *handle) |
963 | { |
964 | if (handle->h_aborted) |
965 | return 1; |
966 | return is_journal_aborted(handle->h_transaction->t_journal); |
967 | } |
968 | |
969 | static inline void journal_abort_handle(handle_t *handle) |
970 | { |
971 | handle->h_aborted = 1; |
972 | } |
973 | |
974 | #endif /* __KERNEL__ */ |
975 | |
976 | /* Comparison functions for transaction IDs: perform comparisons using |
977 | * modulo arithmetic so that they work over sequence number wraps. */ |
978 | |
979 | static inline int tid_gt(tid_t x, tid_t y) |
980 | { |
981 | int difference = (x - y); |
982 | return (difference > 0); |
983 | } |
984 | |
985 | static inline int tid_geq(tid_t x, tid_t y) |
986 | { |
987 | int difference = (x - y); |
988 | return (difference >= 0); |
989 | } |
990 | |
991 | extern int journal_blocks_per_page(struct inode *inode); |
992 | |
993 | /* |
994 | * Return the minimum number of blocks which must be free in the journal |
995 | * before a new transaction may be started. Must be called under j_state_lock. |
996 | */ |
997 | static inline int jbd_space_needed(journal_t *journal) |
998 | { |
999 | int nblocks = journal->j_max_transaction_buffers; |
1000 | if (journal->j_committing_transaction) |
1001 | nblocks += journal->j_committing_transaction-> |
1002 | t_outstanding_credits; |
1003 | return nblocks; |
1004 | } |
1005 | |
1006 | /* |
1007 | * Definitions which augment the buffer_head layer |
1008 | */ |
1009 | |
1010 | /* journaling buffer types */ |
1011 | #define BJ_None 0 /* Not journaled */ |
1012 | #define BJ_SyncData 1 /* Normal data: flush before commit */ |
1013 | #define BJ_Metadata 2 /* Normal journaled metadata */ |
1014 | #define BJ_Forget 3 /* Buffer superseded by this transaction */ |
1015 | #define BJ_IO 4 /* Buffer is for temporary IO use */ |
1016 | #define BJ_Shadow 5 /* Buffer contents being shadowed to the log */ |
1017 | #define BJ_LogCtl 6 /* Buffer contains log descriptors */ |
1018 | #define BJ_Reserved 7 /* Buffer is reserved for access by journal */ |
1019 | #define BJ_Locked 8 /* Locked for I/O during commit */ |
1020 | #define BJ_Types 9 |
1021 | |
1022 | extern int jbd_blocks_per_page(struct inode *inode); |
1023 | |
1024 | #ifdef __KERNEL__ |
1025 | |
1026 | #define buffer_trace_init(bh) do {} while (0) |
1027 | #define print_buffer_fields(bh) do {} while (0) |
1028 | #define print_buffer_trace(bh) do {} while (0) |
1029 | #define BUFFER_TRACE(bh, info) do {} while (0) |
1030 | #define BUFFER_TRACE2(bh, bh2, info) do {} while (0) |
1031 | #define JBUFFER_TRACE(jh, info) do {} while (0) |
1032 | |
1033 | #endif /* __KERNEL__ */ |
1034 | |
1035 | #endif /* _LINUX_JBD_H */ |
1036 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9