ReactOS  0.4.14-dev-98-gb0d4763
journal-head.h
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1 /*
2  * include/linux/journal-head.h
3  *
4  * buffer_head fields for JBD
5  *
6  * 27 May 2001 Andrew Morton <akpm@digeo.com>
7  * Created - pulled out of fs.h
8  */
9 
10 #ifndef JOURNAL_HEAD_H_INCLUDED
11 #define JOURNAL_HEAD_H_INCLUDED
12 
13 typedef unsigned int tid_t; /* Unique transaction ID */
14 typedef struct transaction_s transaction_t; /* Compound transaction type */
15 struct buffer_head;
16 
17 struct journal_head {
18  /*
19  * Points back to our buffer_head. [jbd_lock_bh_journal_head()]
20  */
21  struct buffer_head *b_bh;
22 
23  /*
24  * Reference count - see description in journal.c
25  * [jbd_lock_bh_journal_head()]
26  */
27  int b_jcount;
28 
29  /*
30  * Journalling list for this buffer [jbd_lock_bh_state()]
31  */
32  unsigned b_jlist;
33 
34  /*
35  * This flag signals the buffer has been modified by
36  * the currently running transaction
37  * [jbd_lock_bh_state()]
38  */
39  unsigned b_modified;
40 
41  /*
42  * Copy of the buffer data frozen for writing to the log.
43  * [jbd_lock_bh_state()]
44  */
46 
47  /*
48  * Pointer to a saved copy of the buffer containing no uncommitted
49  * deallocation references, so that allocations can avoid overwriting
50  * uncommitted deletes. [jbd_lock_bh_state()]
51  */
53 
54  /*
55  * Pointer to the compound transaction which owns this buffer's
56  * metadata: either the running transaction or the committing
57  * transaction (if there is one). Only applies to buffers on a
58  * transaction's data or metadata journaling list.
59  * [j_list_lock] [jbd_lock_bh_state()]
60  */
62 
63  /*
64  * Pointer to the running compound transaction which is currently
65  * modifying the buffer's metadata, if there was already a transaction
66  * committing it when the new transaction touched it.
67  * [t_list_lock] [jbd_lock_bh_state()]
68  */
70 
71  /*
72  * Doubly-linked list of buffers on a transaction's data, metadata or
73  * forget queue. [t_list_lock] [jbd_lock_bh_state()]
74  */
76 
77  /*
78  * Pointer to the compound transaction against which this buffer
79  * is checkpointed. Only dirty buffers can be checkpointed.
80  * [j_list_lock]
81  */
83 
84  /*
85  * Doubly-linked list of buffers still remaining to be flushed
86  * before an old transaction can be checkpointed.
87  * [j_list_lock]
88  */
90 };
91 
92 #endif /* JOURNAL_HEAD_H_INCLUDED */
struct buffer_head * b_bh
Definition: journal-head.h:21
transaction_t * b_next_transaction
Definition: journal-head.h:69
transaction_t * b_transaction
Definition: journal-head.h:61
char * b_committed_data
Definition: journal-head.h:52
struct journal_head * b_cpprev
Definition: journal-head.h:89
struct journal_head * b_tprev
Definition: journal-head.h:75
struct journal_head * b_tnext
Definition: journal-head.h:75
struct journal_head * b_cpnext
Definition: journal-head.h:89
transaction_t * b_cp_transaction
Definition: journal-head.h:82
unsigned b_modified
Definition: journal-head.h:39
unsigned int tid_t
Definition: journal-head.h:13
char * b_frozen_data
Definition: journal-head.h:45
struct transaction_s transaction_t
Definition: journal-head.h:14
unsigned b_jlist
Definition: journal-head.h:32