include/ext4fs.h

   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  * Ext4 Extent data structures are taken from  original ext4 fs code
   8  * as found in the linux kernel.
   9  *
  10  * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
  11  * Written by Alex Tomas <alex@clusterfs.com>
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License version 2 as
  15  * published by the Free Software Foundation.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25  */
  26
  27 #ifndef __EXT4__
  28 #define __EXT4__
  29 #include <ext_common.h>
  30
  31 struct disk_partition;
  32
  33 #define EXT4_INDEX_FL           0x00001000 /* Inode uses hash tree index */
  34 #define EXT4_EXTENTS_FL         0x00080000 /* Inode uses extents */
  35 #define EXT4_EXT_MAGIC                  0xf30a
  36 #define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
  37 #define EXT4_FEATURE_RO_COMPAT_METADATA_CSUM 0x0400
  38 #define EXT4_FEATURE_INCOMPAT_EXTENTS   0x0040
  39 #define EXT4_FEATURE_INCOMPAT_64BIT     0x0080
  40 #define EXT4_INDIRECT_BLOCKS            12
  41
  42 #define EXT4_BG_INODE_UNINIT            0x0001
  43 #define EXT4_BG_BLOCK_UNINIT            0x0002
  44 #define EXT4_BG_INODE_ZEROED            0x0004
  45
  46 /*
  47  * ext4_inode has i_block array (60 bytes total).
  48  * The first 12 bytes store ext4_extent_header;
  49  * the remainder stores an array of ext4_extent.
  50  */
  51
  52 /*
  53  * This is the extent on-disk structure.
  54  * It's used at the bottom of the tree.
  55  */
  56 struct ext4_extent {
  57         __le32  ee_block;       /* first logical block extent covers */
  58         __le16  ee_len;         /* number of blocks covered by extent */
  59         __le16  ee_start_hi;    /* high 16 bits of physical block */
  60         __le32  ee_start_lo;    /* low 32 bits of physical block */
  61 };
  62
  63 /*
  64  * This is index on-disk structure.
  65  * It's used at all the levels except the bottom.
  66  */
  67 struct ext4_extent_idx {
  68         __le32  ei_block;       /* index covers logical blocks from 'block' */
  69         __le32  ei_leaf_lo;     /* pointer to the physical block of the next *
  70                                  * level. leaf or next index could be there */
  71         __le16  ei_leaf_hi;     /* high 16 bits of physical block */
  72         __u16   ei_unused;
  73 };
  74
  75 /* Each block (leaves and indexes), even inode-stored has header. */
  76 struct ext4_extent_header {
  77         __le16  eh_magic;       /* probably will support different formats */
  78         __le16  eh_entries;     /* number of valid entries */
  79         __le16  eh_max;         /* capacity of store in entries */
  80         __le16  eh_depth;       /* has tree real underlying blocks? */
  81         __le32  eh_generation;  /* generation of the tree */
  82 };
  83
  84 struct ext_filesystem {
  85         /* Total Sector of partition */
  86         uint64_t total_sect;
  87         /* Block size  of partition */
  88         uint32_t blksz;
  89         /* Inode size of partition */
  90         uint32_t inodesz;
  91         /* Sectors per Block */
  92         uint32_t sect_perblk;
  93         /* Group Descriptor size */
  94         uint16_t gdsize;
  95         /* Group Descriptor Block Number */
  96         uint32_t gdtable_blkno;
  97         /* Total block groups of partition */
  98         uint32_t no_blkgrp;
  99         /* No of blocks required for bgdtable */
 100         uint32_t no_blk_pergdt;
 101         /* Superblock */
 102         struct ext2_sblock *sb;
 103         /* Block group descritpor table */
 104         char *gdtable;
 105
 106         /* Block Bitmap Related */
 107         unsigned char **blk_bmaps;
 108         long int curr_blkno;
 109         uint16_t first_pass_bbmap;
 110
 111         /* Inode Bitmap Related */
 112         unsigned char **inode_bmaps;
 113         int curr_inode_no;
 114         uint16_t first_pass_ibmap;
 115
 116         /* Journal Related */
 117
 118         /* Block Device Descriptor */
 119         struct blk_desc *dev_desc;
 120 };
 121
 122 struct ext_block_cache {
 123         char *buf;
 124         lbaint_t block;
 125         int size;
 126 };
 127
 128 extern struct ext2_data *ext4fs_root;
 129 extern struct ext2fs_node *ext4fs_file;
 130
 131 #if defined(CONFIG_EXT4_WRITE)
 132 extern struct ext2_inode *g_parent_inode;
 133 extern int gd_index;
 134 extern int gindex;
 135
 136 int ext4fs_init(void);
 137 void ext4fs_deinit(void);
 138 int ext4fs_filename_unlink(char *filename);
 139 int ext4fs_write(const char *fname, const char *buffer,
 140                                  unsigned long sizebytes, int type);
 141 int ext4_write_file(const char *filename, void *buf, loff_t offset, loff_t len,
 142                     loff_t *actwrite);
 143 int ext4fs_create_link(const char *target, const char *fname);
 144 #endif
 145
 146 struct ext_filesystem *get_fs(void);
 147 int ext4fs_open(const char *filename, loff_t *len);
 148 int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread);
 149 int ext4fs_mount(unsigned part_length);
 150 void ext4fs_close(void);
 151 void ext4fs_reinit_global(void);
 152 int ext4fs_ls(const char *dirname);
 153 int ext4fs_exists(const char *filename);
 154 int ext4fs_size(const char *filename, loff_t *size);
 155 void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot);
 156 int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf);
 157 void ext4fs_set_blk_dev(struct blk_desc *rbdd, struct disk_partition *info);
 158 long int read_allocated_block(struct ext2_inode *inode, int fileblock,
 159                               struct ext_block_cache *cache);
 160 int ext4fs_probe(struct blk_desc *fs_dev_desc,
 161                  struct disk_partition *fs_partition);
 162 int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
 163                    loff_t *actread);
 164 int ext4_read_superblock(char *buffer);
 165 int ext4fs_uuid(char *uuid_str);
 166 void ext_cache_init(struct ext_block_cache *cache);
 167 void ext_cache_fini(struct ext_block_cache *cache);
 168 int ext_cache_read(struct ext_block_cache *cache, lbaint_t block, int size);
 169 #endif