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Diffstat (limited to 'fs/ext4/ext4_journal.h')
| -rw-r--r-- | fs/ext4/ext4_journal.h | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/fs/ext4/ext4_journal.h b/fs/ext4/ext4_journal.h new file mode 100644 index 000000000..acc1c5163 --- /dev/null +++ b/fs/ext4/ext4_journal.h @@ -0,0 +1,141 @@ +/* + * (C) Copyright 2011 - 2012 Samsung Electronics + * EXT4 filesystem implementation in Uboot by + * Uma Shankar <uma.shankar@samsung.com> + * Manjunatha C Achar <a.manjunatha@samsung.com> + * + * Journal data structures and headers for Journaling feature of ext4 + * have been referred from JBD2 (Journaling Block device 2) + * implementation in Linux Kernel. + * + * Written by Stephen C. Tweedie <sct@redhat.com> + * + * Copyright 1998-2000 Red Hat, Inc --- All Rights Reserved + * This file is part of the Linux kernel and is made available under + * the terms of the GNU General Public License, version 2, or at your + * option, any later version, incorporated herein by reference. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#ifndef __EXT4_JRNL__ +#define __EXT4_JRNL__ + +#define EXT2_JOURNAL_INO 8 /* Journal inode */ +#define EXT2_JOURNAL_SUPERBLOCK 0 /* Journal Superblock number */ + +#define JBD2_FEATURE_COMPAT_CHECKSUM 0x00000001 +#define EXT3_JOURNAL_MAGIC_NUMBER 0xc03b3998U +#define TRANSACTION_RUNNING 1 +#define TRANSACTION_COMPLETE 0 +#define EXT3_FEATURE_INCOMPAT_RECOVER 0x0004 /* Needs recovery */ +#define EXT3_JOURNAL_DESCRIPTOR_BLOCK 1 +#define EXT3_JOURNAL_COMMIT_BLOCK 2 +#define EXT3_JOURNAL_SUPERBLOCK_V1 3 +#define EXT3_JOURNAL_SUPERBLOCK_V2 4 +#define EXT3_JOURNAL_REVOKE_BLOCK 5 +#define EXT3_JOURNAL_FLAG_ESCAPE 1 +#define EXT3_JOURNAL_FLAG_SAME_UUID 2 +#define EXT3_JOURNAL_FLAG_DELETED 4 +#define EXT3_JOURNAL_FLAG_LAST_TAG 8 + +/* Maximum entries in 1 journal transaction */ +#define MAX_JOURNAL_ENTRIES 100 +struct journal_log { + char *buf; + int blknr; +}; + +struct dirty_blocks { + char *buf; + int blknr; +}; + +/* Standard header for all descriptor blocks: */ +struct journal_header_t { + __u32 h_magic; + __u32 h_blocktype; + __u32 h_sequence; +}; + +/* The journal superblock. All fields are in big-endian byte order. */ +struct journal_superblock_t { + /* 0x0000 */ + struct journal_header_t s_header; + + /* Static information describing the journal */ + __u32 s_blocksize; /* journal device blocksize */ + __u32 s_maxlen; /* total blocks in journal file */ + __u32 s_first; /* first block of log information */ + + /* Dynamic information describing the current state of the log */ + __u32 s_sequence; /* first commit ID expected in log */ + __u32 s_start; /* blocknr of start of log */ + + /* Error value, as set by journal_abort(). */ + __s32 s_errno; + + /* Remaining fields are only valid in a version-2 superblock */ + __u32 s_feature_compat; /* compatible feature set */ + __u32 s_feature_incompat; /* incompatible feature set */ + __u32 s_feature_ro_compat; /* readonly-compatible feature set */ + /* 0x0030 */ + __u8 s_uuid[16]; /* 128-bit uuid for journal */ + + /* 0x0040 */ + __u32 s_nr_users; /* Nr of filesystems sharing log */ + + __u32 s_dynsuper; /* Blocknr of dynamic superblock copy */ + + /* 0x0048 */ + __u32 s_max_transaction; /* Limit of journal blocks per trans. */ + __u32 s_max_trans_data; /* Limit of data blocks per trans. */ + + /* 0x0050 */ + __u32 s_padding[44]; + + /* 0x0100 */ + __u8 s_users[16 * 48]; /* ids of all fs'es sharing the log */ + /* 0x0400 */ +} ; + +struct ext3_journal_block_tag { + uint32_t block; + uint32_t flags; +}; + +struct journal_revoke_header_t { + struct journal_header_t r_header; + int r_count; /* Count of bytes used in the block */ +}; + +struct revoke_blk_list { + char *content; /* revoke block itself */ + struct revoke_blk_list *next; +}; + +extern struct ext2_data *ext4fs_root; + +int ext4fs_init_journal(void); +int ext4fs_log_gdt(char *gd_table); +int ext4fs_check_journal_state(int recovery_flag); +int ext4fs_log_journal(char *journal_buffer, long int blknr); +int ext4fs_put_metadata(char *metadata_buffer, long int blknr); +void ext4fs_update_journal(void); +void ext4fs_dump_metadata(void); +void ext4fs_push_revoke_blk(char *buffer); +void ext4fs_free_journal(void); +void ext4fs_free_revoke_blks(void); +#endif |