xref: /openbmc/u-boot/fs/ext4/ext4_journal.h (revision 20c700f8)
1 /*
2  * (C) Copyright 2011 - 2012 Samsung Electronics
3  * EXT4 filesystem implementation in Uboot by
4  * Uma Shankar <uma.shankar@samsung.com>
5  * Manjunatha C Achar <a.manjunatha@samsung.com>
6  *
7  * Journal data structures and headers for Journaling feature of ext4
8  * have been referred from JBD2 (Journaling Block device 2)
9  * implementation in Linux Kernel.
10  *
11  * Written by Stephen C. Tweedie <sct@redhat.com>
12  *
13  * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved
14  * SPDX-License-Identifier:	GPL-2.0+
15  */
16 
17 #ifndef __EXT4_JRNL__
18 #define __EXT4_JRNL__
19 
20 #define EXT2_JOURNAL_INO		8	/* Journal inode */
21 #define EXT2_JOURNAL_SUPERBLOCK	0	/* Journal  Superblock number */
22 
23 #define JBD2_FEATURE_COMPAT_CHECKSUM	0x00000001
24 #define EXT3_JOURNAL_MAGIC_NUMBER	0xc03b3998U
25 #define TRANSACTION_RUNNING		1
26 #define TRANSACTION_COMPLETE		0
27 #define EXT3_FEATURE_INCOMPAT_RECOVER	0x0004	/* Needs recovery */
28 #define EXT3_JOURNAL_DESCRIPTOR_BLOCK	1
29 #define EXT3_JOURNAL_COMMIT_BLOCK	2
30 #define EXT3_JOURNAL_SUPERBLOCK_V1	3
31 #define EXT3_JOURNAL_SUPERBLOCK_V2	4
32 #define EXT3_JOURNAL_REVOKE_BLOCK	5
33 #define EXT3_JOURNAL_FLAG_ESCAPE	1
34 #define EXT3_JOURNAL_FLAG_SAME_UUID	2
35 #define EXT3_JOURNAL_FLAG_DELETED	4
36 #define EXT3_JOURNAL_FLAG_LAST_TAG	8
37 
38 /* Maximum entries in 1 journal transaction */
39 #define MAX_JOURNAL_ENTRIES 100
40 struct journal_log {
41 	char *buf;
42 	int blknr;
43 };
44 
45 struct dirty_blocks {
46 	char *buf;
47 	int blknr;
48 };
49 
50 /* Standard header for all descriptor blocks: */
51 struct journal_header_t {
52 	__be32 h_magic;
53 	__be32 h_blocktype;
54 	__be32 h_sequence;
55 };
56 
57 /* The journal superblock.  All fields are in big-endian byte order. */
58 struct journal_superblock_t {
59 	/* 0x0000 */
60 	struct journal_header_t s_header;
61 
62 	/* Static information describing the journal */
63 	__be32 s_blocksize;	/* journal device blocksize */
64 	__be32 s_maxlen;		/* total blocks in journal file */
65 	__be32 s_first;		/* first block of log information */
66 
67 	/* Dynamic information describing the current state of the log */
68 	__be32 s_sequence;	/* first commit ID expected in log */
69 	__be32 s_start;		/* blocknr of start of log */
70 
71 	/* Error value, as set by journal_abort(). */
72 	__be32 s_errno;
73 
74 	/* Remaining fields are only valid in a version-2 superblock */
75 	__be32 s_feature_compat;	/* compatible feature set */
76 	__be32 s_feature_incompat;	/* incompatible feature set */
77 	__be32 s_feature_ro_compat;	/* readonly-compatible feature set */
78 	/* 0x0030 */
79 	__u8 s_uuid[16];	/* 128-bit uuid for journal */
80 
81 	/* 0x0040 */
82 	__be32 s_nr_users;	/* Nr of filesystems sharing log */
83 
84 	__be32 s_dynsuper;	/* Blocknr of dynamic superblock copy */
85 
86 	/* 0x0048 */
87 	__be32 s_max_transaction;	/* Limit of journal blocks per trans. */
88 	__be32 s_max_trans_data;	/* Limit of data blocks per trans. */
89 
90 	/* 0x0050 */
91 	__be32 s_padding[44];
92 
93 	/* 0x0100 */
94 	__u8 s_users[16 * 48];	/* ids of all fs'es sharing the log */
95 	/* 0x0400 */
96 } ;
97 
98 struct ext3_journal_block_tag {
99 	__be32 block;
100 	__be32 flags;
101 };
102 
103 struct journal_revoke_header_t {
104 	struct journal_header_t r_header;
105 	__be32 r_count;		/* Count of bytes used in the block */
106 };
107 
108 struct revoke_blk_list {
109 	char *content;		/* revoke block itself */
110 	struct revoke_blk_list *next;
111 };
112 
113 extern struct ext2_data *ext4fs_root;
114 
115 int ext4fs_init_journal(void);
116 int ext4fs_log_gdt(char *gd_table);
117 int ext4fs_check_journal_state(int recovery_flag);
118 int ext4fs_log_journal(char *journal_buffer, uint32_t blknr);
119 int ext4fs_put_metadata(char *metadata_buffer, uint32_t blknr);
120 void ext4fs_update_journal(void);
121 void ext4fs_dump_metadata(void);
122 void ext4fs_push_revoke_blk(char *buffer);
123 void ext4fs_free_journal(void);
124 void ext4fs_free_revoke_blks(void);
125 #endif
126