u-boot/fs/ext2/ext2fs.c
Aaron Pace a2740dd00d ext2fs: Fix optimization bug for doubly-indirect block pointers
Doubly-indirect block numbers are compared against the first-level
indirect block when checking for a cached copy.  This is causing the
doubly-indirect block to be re-read each time it is accessed.
Repairing this reduces load time for a 70M file from 72 seconds
to 38 seconds.

Signed-off-by: Aaron Pace <Aaron.Pace@alcatel-lucent.com>
2010-08-07 22:44:08 +02:00

891 lines
21 KiB
C

/*
* (C) Copyright 2004
* esd gmbh <www.esd-electronics.com>
* Reinhard Arlt <reinhard.arlt@esd-electronics.com>
*
* based on code from grub2 fs/ext2.c and fs/fshelp.c by
*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
*
* 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.
*/
#include <common.h>
#include <ext2fs.h>
#include <malloc.h>
#include <asm/byteorder.h>
extern int ext2fs_devread (int sector, int byte_offset, int byte_len,
char *buf);
/* Magic value used to identify an ext2 filesystem. */
#define EXT2_MAGIC 0xEF53
/* Amount of indirect blocks in an inode. */
#define INDIRECT_BLOCKS 12
/* Maximum lenght of a pathname. */
#define EXT2_PATH_MAX 4096
/* Maximum nesting of symlinks, used to prevent a loop. */
#define EXT2_MAX_SYMLINKCNT 8
/* Filetype used in directory entry. */
#define FILETYPE_UNKNOWN 0
#define FILETYPE_REG 1
#define FILETYPE_DIRECTORY 2
#define FILETYPE_SYMLINK 7
/* Filetype information as used in inodes. */
#define FILETYPE_INO_MASK 0170000
#define FILETYPE_INO_REG 0100000
#define FILETYPE_INO_DIRECTORY 0040000
#define FILETYPE_INO_SYMLINK 0120000
/* Bits used as offset in sector */
#define DISK_SECTOR_BITS 9
/* Log2 size of ext2 block in 512 blocks. */
#define LOG2_EXT2_BLOCK_SIZE(data) (__le32_to_cpu (data->sblock.log2_block_size) + 1)
/* Log2 size of ext2 block in bytes. */
#define LOG2_BLOCK_SIZE(data) (__le32_to_cpu (data->sblock.log2_block_size) + 10)
/* The size of an ext2 block in bytes. */
#define EXT2_BLOCK_SIZE(data) (1 << LOG2_BLOCK_SIZE(data))
/* The ext2 superblock. */
struct ext2_sblock {
uint32_t total_inodes;
uint32_t total_blocks;
uint32_t reserved_blocks;
uint32_t free_blocks;
uint32_t free_inodes;
uint32_t first_data_block;
uint32_t log2_block_size;
uint32_t log2_fragment_size;
uint32_t blocks_per_group;
uint32_t fragments_per_group;
uint32_t inodes_per_group;
uint32_t mtime;
uint32_t utime;
uint16_t mnt_count;
uint16_t max_mnt_count;
uint16_t magic;
uint16_t fs_state;
uint16_t error_handling;
uint16_t minor_revision_level;
uint32_t lastcheck;
uint32_t checkinterval;
uint32_t creator_os;
uint32_t revision_level;
uint16_t uid_reserved;
uint16_t gid_reserved;
uint32_t first_inode;
uint16_t inode_size;
uint16_t block_group_number;
uint32_t feature_compatibility;
uint32_t feature_incompat;
uint32_t feature_ro_compat;
uint32_t unique_id[4];
char volume_name[16];
char last_mounted_on[64];
uint32_t compression_info;
};
/* The ext2 blockgroup. */
struct ext2_block_group {
uint32_t block_id;
uint32_t inode_id;
uint32_t inode_table_id;
uint16_t free_blocks;
uint16_t free_inodes;
uint16_t used_dir_cnt;
uint32_t reserved[3];
};
/* The ext2 inode. */
struct ext2_inode {
uint16_t mode;
uint16_t uid;
uint32_t size;
uint32_t atime;
uint32_t ctime;
uint32_t mtime;
uint32_t dtime;
uint16_t gid;
uint16_t nlinks;
uint32_t blockcnt; /* Blocks of 512 bytes!! */
uint32_t flags;
uint32_t osd1;
union {
struct datablocks {
uint32_t dir_blocks[INDIRECT_BLOCKS];
uint32_t indir_block;
uint32_t double_indir_block;
uint32_t tripple_indir_block;
} blocks;
char symlink[60];
} b;
uint32_t version;
uint32_t acl;
uint32_t dir_acl;
uint32_t fragment_addr;
uint32_t osd2[3];
};
/* The header of an ext2 directory entry. */
struct ext2_dirent {
uint32_t inode;
uint16_t direntlen;
uint8_t namelen;
uint8_t filetype;
};
struct ext2fs_node {
struct ext2_data *data;
struct ext2_inode inode;
int ino;
int inode_read;
};
/* Information about a "mounted" ext2 filesystem. */
struct ext2_data {
struct ext2_sblock sblock;
struct ext2_inode *inode;
struct ext2fs_node diropen;
};
typedef struct ext2fs_node *ext2fs_node_t;
struct ext2_data *ext2fs_root = NULL;
ext2fs_node_t ext2fs_file = NULL;
int symlinknest = 0;
uint32_t *indir1_block = NULL;
int indir1_size = 0;
int indir1_blkno = -1;
uint32_t *indir2_block = NULL;
int indir2_size = 0;
int indir2_blkno = -1;
static unsigned int inode_size;
static int ext2fs_blockgroup
(struct ext2_data *data, int group, struct ext2_block_group *blkgrp) {
unsigned int blkno;
unsigned int blkoff;
unsigned int desc_per_blk;
desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 +
group / desc_per_blk;
blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
#ifdef DEBUG
printf ("ext2fs read %d group descriptor (blkno %d blkoff %d)\n",
group, blkno, blkoff);
#endif
return (ext2fs_devread (blkno << LOG2_EXT2_BLOCK_SIZE(data),
blkoff, sizeof(struct ext2_block_group), (char *)blkgrp));
}
static int ext2fs_read_inode
(struct ext2_data *data, int ino, struct ext2_inode *inode) {
struct ext2_block_group blkgrp;
struct ext2_sblock *sblock = &data->sblock;
int inodes_per_block;
int status;
unsigned int blkno;
unsigned int blkoff;
#ifdef DEBUG
printf ("ext2fs read inode %d, inode_size %d\n", ino, inode_size);
#endif
/* It is easier to calculate if the first inode is 0. */
ino--;
status = ext2fs_blockgroup (data, ino / __le32_to_cpu
(sblock->inodes_per_group), &blkgrp);
if (status == 0) {
return (0);
}
inodes_per_block = EXT2_BLOCK_SIZE(data) / inode_size;
blkno = __le32_to_cpu (blkgrp.inode_table_id) +
(ino % __le32_to_cpu (sblock->inodes_per_group))
/ inodes_per_block;
blkoff = (ino % inodes_per_block) * inode_size;
#ifdef DEBUG
printf ("ext2fs read inode blkno %d blkoff %d\n", blkno, blkoff);
#endif
/* Read the inode. */
status = ext2fs_devread (blkno << LOG2_EXT2_BLOCK_SIZE (data), blkoff,
sizeof (struct ext2_inode), (char *) inode);
if (status == 0) {
return (0);
}
return (1);
}
void ext2fs_free_node (ext2fs_node_t node, ext2fs_node_t currroot) {
if ((node != &ext2fs_root->diropen) && (node != currroot)) {
free (node);
}
}
static int ext2fs_read_block (ext2fs_node_t node, int fileblock) {
struct ext2_data *data = node->data;
struct ext2_inode *inode = &node->inode;
int blknr;
int blksz = EXT2_BLOCK_SIZE (data);
int log2_blksz = LOG2_EXT2_BLOCK_SIZE (data);
int status;
/* Direct blocks. */
if (fileblock < INDIRECT_BLOCKS) {
blknr = __le32_to_cpu (inode->b.blocks.dir_blocks[fileblock]);
}
/* Indirect. */
else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
if (indir1_block == NULL) {
indir1_block = (uint32_t *) malloc (blksz);
if (indir1_block == NULL) {
printf ("** ext2fs read block (indir 1) malloc failed. **\n");
return (-1);
}
indir1_size = blksz;
indir1_blkno = -1;
}
if (blksz != indir1_size) {
free (indir1_block);
indir1_block = NULL;
indir1_size = 0;
indir1_blkno = -1;
indir1_block = (uint32_t *) malloc (blksz);
if (indir1_block == NULL) {
printf ("** ext2fs read block (indir 1) malloc failed. **\n");
return (-1);
}
indir1_size = blksz;
}
if ((__le32_to_cpu (inode->b.blocks.indir_block) <<
log2_blksz) != indir1_blkno) {
status = ext2fs_devread (__le32_to_cpu(inode->b.blocks.indir_block) << log2_blksz,
0, blksz,
(char *) indir1_block);
if (status == 0) {
printf ("** ext2fs read block (indir 1) failed. **\n");
return (0);
}
indir1_blkno =
__le32_to_cpu (inode->b.blocks.
indir_block) << log2_blksz;
}
blknr = __le32_to_cpu (indir1_block
[fileblock - INDIRECT_BLOCKS]);
}
/* Double indirect. */
else if (fileblock <
(INDIRECT_BLOCKS + (blksz / 4 * (blksz / 4 + 1)))) {
unsigned int perblock = blksz / 4;
unsigned int rblock = fileblock - (INDIRECT_BLOCKS
+ blksz / 4);
if (indir1_block == NULL) {
indir1_block = (uint32_t *) malloc (blksz);
if (indir1_block == NULL) {
printf ("** ext2fs read block (indir 2 1) malloc failed. **\n");
return (-1);
}
indir1_size = blksz;
indir1_blkno = -1;
}
if (blksz != indir1_size) {
free (indir1_block);
indir1_block = NULL;
indir1_size = 0;
indir1_blkno = -1;
indir1_block = (uint32_t *) malloc (blksz);
if (indir1_block == NULL) {
printf ("** ext2fs read block (indir 2 1) malloc failed. **\n");
return (-1);
}
indir1_size = blksz;
}
if ((__le32_to_cpu (inode->b.blocks.double_indir_block) <<
log2_blksz) != indir1_blkno) {
status = ext2fs_devread (__le32_to_cpu(inode->b.blocks.double_indir_block) << log2_blksz,
0, blksz,
(char *) indir1_block);
if (status == 0) {
printf ("** ext2fs read block (indir 2 1) failed. **\n");
return (-1);
}
indir1_blkno =
__le32_to_cpu (inode->b.blocks.double_indir_block) << log2_blksz;
}
if (indir2_block == NULL) {
indir2_block = (uint32_t *) malloc (blksz);
if (indir2_block == NULL) {
printf ("** ext2fs read block (indir 2 2) malloc failed. **\n");
return (-1);
}
indir2_size = blksz;
indir2_blkno = -1;
}
if (blksz != indir2_size) {
free (indir2_block);
indir2_block = NULL;
indir2_size = 0;
indir2_blkno = -1;
indir2_block = (uint32_t *) malloc (blksz);
if (indir2_block == NULL) {
printf ("** ext2fs read block (indir 2 2) malloc failed. **\n");
return (-1);
}
indir2_size = blksz;
}
if ((__le32_to_cpu (indir1_block[rblock / perblock]) <<
log2_blksz) != indir2_blkno) {
status = ext2fs_devread (__le32_to_cpu(indir1_block[rblock / perblock]) << log2_blksz,
0, blksz,
(char *) indir2_block);
if (status == 0) {
printf ("** ext2fs read block (indir 2 2) failed. **\n");
return (-1);
}
indir2_blkno =
__le32_to_cpu (indir1_block[rblock / perblock]) << log2_blksz;
}
blknr = __le32_to_cpu (indir2_block[rblock % perblock]);
}
/* Tripple indirect. */
else {
printf ("** ext2fs doesn't support tripple indirect blocks. **\n");
return (-1);
}
#ifdef DEBUG
printf ("ext2fs_read_block %08x\n", blknr);
#endif
return (blknr);
}
int ext2fs_read_file
(ext2fs_node_t node, int pos, unsigned int len, char *buf) {
int i;
int blockcnt;
int log2blocksize = LOG2_EXT2_BLOCK_SIZE (node->data);
int blocksize = 1 << (log2blocksize + DISK_SECTOR_BITS);
unsigned int filesize = __le32_to_cpu(node->inode.size);
/* Adjust len so it we can't read past the end of the file. */
if (len > filesize) {
len = filesize;
}
blockcnt = ((len + pos) + blocksize - 1) / blocksize;
for (i = pos / blocksize; i < blockcnt; i++) {
int blknr;
int blockoff = pos % blocksize;
int blockend = blocksize;
int skipfirst = 0;
blknr = ext2fs_read_block (node, i);
if (blknr < 0) {
return (-1);
}
blknr = blknr << log2blocksize;
/* Last block. */
if (i == blockcnt - 1) {
blockend = (len + pos) % blocksize;
/* The last portion is exactly blocksize. */
if (!blockend) {
blockend = blocksize;
}
}
/* First block. */
if (i == pos / blocksize) {
skipfirst = blockoff;
blockend -= skipfirst;
}
/* If the block number is 0 this block is not stored on disk but
is zero filled instead. */
if (blknr) {
int status;
status = ext2fs_devread (blknr, skipfirst, blockend, buf);
if (status == 0) {
return (-1);
}
} else {
memset (buf, 0, blocksize - skipfirst);
}
buf += blocksize - skipfirst;
}
return (len);
}
static int ext2fs_iterate_dir (ext2fs_node_t dir, char *name, ext2fs_node_t * fnode, int *ftype)
{
unsigned int fpos = 0;
int status;
struct ext2fs_node *diro = (struct ext2fs_node *) dir;
#ifdef DEBUG
if (name != NULL)
printf ("Iterate dir %s\n", name);
#endif /* of DEBUG */
if (!diro->inode_read) {
status = ext2fs_read_inode (diro->data, diro->ino,
&diro->inode);
if (status == 0) {
return (0);
}
}
/* Search the file. */
while (fpos < __le32_to_cpu (diro->inode.size)) {
struct ext2_dirent dirent;
status = ext2fs_read_file (diro, fpos,
sizeof (struct ext2_dirent),
(char *) &dirent);
if (status < 1) {
return (0);
}
if (dirent.namelen != 0) {
char filename[dirent.namelen + 1];
ext2fs_node_t fdiro;
int type = FILETYPE_UNKNOWN;
status = ext2fs_read_file (diro,
fpos + sizeof (struct ext2_dirent),
dirent.namelen, filename);
if (status < 1) {
return (0);
}
fdiro = malloc (sizeof (struct ext2fs_node));
if (!fdiro) {
return (0);
}
fdiro->data = diro->data;
fdiro->ino = __le32_to_cpu (dirent.inode);
filename[dirent.namelen] = '\0';
if (dirent.filetype != FILETYPE_UNKNOWN) {
fdiro->inode_read = 0;
if (dirent.filetype == FILETYPE_DIRECTORY) {
type = FILETYPE_DIRECTORY;
} else if (dirent.filetype ==
FILETYPE_SYMLINK) {
type = FILETYPE_SYMLINK;
} else if (dirent.filetype == FILETYPE_REG) {
type = FILETYPE_REG;
}
} else {
/* The filetype can not be read from the dirent, get it from inode */
status = ext2fs_read_inode (diro->data,
__le32_to_cpu(dirent.inode),
&fdiro->inode);
if (status == 0) {
free (fdiro);
return (0);
}
fdiro->inode_read = 1;
if ((__le16_to_cpu (fdiro->inode.mode) &
FILETYPE_INO_MASK) ==
FILETYPE_INO_DIRECTORY) {
type = FILETYPE_DIRECTORY;
} else if ((__le16_to_cpu (fdiro->inode.mode)
& FILETYPE_INO_MASK) ==
FILETYPE_INO_SYMLINK) {
type = FILETYPE_SYMLINK;
} else if ((__le16_to_cpu (fdiro->inode.mode)
& FILETYPE_INO_MASK) ==
FILETYPE_INO_REG) {
type = FILETYPE_REG;
}
}
#ifdef DEBUG
printf ("iterate >%s<\n", filename);
#endif /* of DEBUG */
if ((name != NULL) && (fnode != NULL)
&& (ftype != NULL)) {
if (strcmp (filename, name) == 0) {
*ftype = type;
*fnode = fdiro;
return (1);
}
} else {
if (fdiro->inode_read == 0) {
status = ext2fs_read_inode (diro->data,
__le32_to_cpu (dirent.inode),
&fdiro->inode);
if (status == 0) {
free (fdiro);
return (0);
}
fdiro->inode_read = 1;
}
switch (type) {
case FILETYPE_DIRECTORY:
printf ("<DIR> ");
break;
case FILETYPE_SYMLINK:
printf ("<SYM> ");
break;
case FILETYPE_REG:
printf (" ");
break;
default:
printf ("< ? > ");
break;
}
printf ("%10d %s\n",
__le32_to_cpu (fdiro->inode.size),
filename);
}
free (fdiro);
}
fpos += __le16_to_cpu (dirent.direntlen);
}
return (0);
}
static char *ext2fs_read_symlink (ext2fs_node_t node) {
char *symlink;
struct ext2fs_node *diro = node;
int status;
if (!diro->inode_read) {
status = ext2fs_read_inode (diro->data, diro->ino,
&diro->inode);
if (status == 0) {
return (0);
}
}
symlink = malloc (__le32_to_cpu (diro->inode.size) + 1);
if (!symlink) {
return (0);
}
/* If the filesize of the symlink is bigger than
60 the symlink is stored in a separate block,
otherwise it is stored in the inode. */
if (__le32_to_cpu (diro->inode.size) <= 60) {
strncpy (symlink, diro->inode.b.symlink,
__le32_to_cpu (diro->inode.size));
} else {
status = ext2fs_read_file (diro, 0,
__le32_to_cpu (diro->inode.size),
symlink);
if (status == 0) {
free (symlink);
return (0);
}
}
symlink[__le32_to_cpu (diro->inode.size)] = '\0';
return (symlink);
}
int ext2fs_find_file1
(const char *currpath,
ext2fs_node_t currroot, ext2fs_node_t * currfound, int *foundtype) {
char fpath[strlen (currpath) + 1];
char *name = fpath;
char *next;
int status;
int type = FILETYPE_DIRECTORY;
ext2fs_node_t currnode = currroot;
ext2fs_node_t oldnode = currroot;
strncpy (fpath, currpath, strlen (currpath) + 1);
/* Remove all leading slashes. */
while (*name == '/') {
name++;
}
if (!*name) {
*currfound = currnode;
return (1);
}
for (;;) {
int found;
/* Extract the actual part from the pathname. */
next = strchr (name, '/');
if (next) {
/* Remove all leading slashes. */
while (*next == '/') {
*(next++) = '\0';
}
}
/* At this point it is expected that the current node is a directory, check if this is true. */
if (type != FILETYPE_DIRECTORY) {
ext2fs_free_node (currnode, currroot);
return (0);
}
oldnode = currnode;
/* Iterate over the directory. */
found = ext2fs_iterate_dir (currnode, name, &currnode, &type);
if (found == 0) {
return (0);
}
if (found == -1) {
break;
}
/* Read in the symlink and follow it. */
if (type == FILETYPE_SYMLINK) {
char *symlink;
/* Test if the symlink does not loop. */
if (++symlinknest == 8) {
ext2fs_free_node (currnode, currroot);
ext2fs_free_node (oldnode, currroot);
return (0);
}
symlink = ext2fs_read_symlink (currnode);
ext2fs_free_node (currnode, currroot);
if (!symlink) {
ext2fs_free_node (oldnode, currroot);
return (0);
}
#ifdef DEBUG
printf ("Got symlink >%s<\n", symlink);
#endif /* of DEBUG */
/* The symlink is an absolute path, go back to the root inode. */
if (symlink[0] == '/') {
ext2fs_free_node (oldnode, currroot);
oldnode = &ext2fs_root->diropen;
}
/* Lookup the node the symlink points to. */
status = ext2fs_find_file1 (symlink, oldnode,
&currnode, &type);
free (symlink);
if (status == 0) {
ext2fs_free_node (oldnode, currroot);
return (0);
}
}
ext2fs_free_node (oldnode, currroot);
/* Found the node! */
if (!next || *next == '\0') {
*currfound = currnode;
*foundtype = type;
return (1);
}
name = next;
}
return (-1);
}
int ext2fs_find_file
(const char *path,
ext2fs_node_t rootnode, ext2fs_node_t * foundnode, int expecttype) {
int status;
int foundtype = FILETYPE_DIRECTORY;
symlinknest = 0;
if (!path) {
return (0);
}
status = ext2fs_find_file1 (path, rootnode, foundnode, &foundtype);
if (status == 0) {
return (0);
}
/* Check if the node that was found was of the expected type. */
if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) {
return (0);
} else if ((expecttype == FILETYPE_DIRECTORY)
&& (foundtype != expecttype)) {
return (0);
}
return (1);
}
int ext2fs_ls (char *dirname) {
ext2fs_node_t dirnode;
int status;
if (ext2fs_root == NULL) {
return (0);
}
status = ext2fs_find_file (dirname, &ext2fs_root->diropen, &dirnode,
FILETYPE_DIRECTORY);
if (status != 1) {
printf ("** Can not find directory. **\n");
return (1);
}
ext2fs_iterate_dir (dirnode, NULL, NULL, NULL);
ext2fs_free_node (dirnode, &ext2fs_root->diropen);
return (0);
}
int ext2fs_open (char *filename) {
ext2fs_node_t fdiro = NULL;
int status;
int len;
if (ext2fs_root == NULL) {
return (-1);
}
ext2fs_file = NULL;
status = ext2fs_find_file (filename, &ext2fs_root->diropen, &fdiro,
FILETYPE_REG);
if (status == 0) {
goto fail;
}
if (!fdiro->inode_read) {
status = ext2fs_read_inode (fdiro->data, fdiro->ino,
&fdiro->inode);
if (status == 0) {
goto fail;
}
}
len = __le32_to_cpu (fdiro->inode.size);
ext2fs_file = fdiro;
return (len);
fail:
ext2fs_free_node (fdiro, &ext2fs_root->diropen);
return (-1);
}
int ext2fs_close (void
) {
if ((ext2fs_file != NULL) && (ext2fs_root != NULL)) {
ext2fs_free_node (ext2fs_file, &ext2fs_root->diropen);
ext2fs_file = NULL;
}
if (ext2fs_root != NULL) {
free (ext2fs_root);
ext2fs_root = NULL;
}
if (indir1_block != NULL) {
free (indir1_block);
indir1_block = NULL;
indir1_size = 0;
indir1_blkno = -1;
}
if (indir2_block != NULL) {
free (indir2_block);
indir2_block = NULL;
indir2_size = 0;
indir2_blkno = -1;
}
return (0);
}
int ext2fs_read (char *buf, unsigned len) {
int status;
if (ext2fs_root == NULL) {
return (0);
}
if (ext2fs_file == NULL) {
return (0);
}
status = ext2fs_read_file (ext2fs_file, 0, len, buf);
return (status);
}
int ext2fs_mount (unsigned part_length) {
struct ext2_data *data;
int status;
data = malloc (sizeof (struct ext2_data));
if (!data) {
return (0);
}
/* Read the superblock. */
status = ext2fs_devread (1 * 2, 0, sizeof (struct ext2_sblock),
(char *) &data->sblock);
if (status == 0) {
goto fail;
}
/* Make sure this is an ext2 filesystem. */
if (__le16_to_cpu (data->sblock.magic) != EXT2_MAGIC) {
goto fail;
}
if (__le32_to_cpu(data->sblock.revision_level == 0)) {
inode_size = 128;
} else {
inode_size = __le16_to_cpu(data->sblock.inode_size);
}
#ifdef DEBUG
printf("EXT2 rev %d, inode_size %d\n",
__le32_to_cpu(data->sblock.revision_level), inode_size);
#endif
data->diropen.data = data;
data->diropen.ino = 2;
data->diropen.inode_read = 1;
data->inode = &data->diropen.inode;
status = ext2fs_read_inode (data, 2, data->inode);
if (status == 0) {
goto fail;
}
ext2fs_root = data;
return (1);
fail:
printf ("Failed to mount ext2 filesystem...\n");
free (data);
ext2fs_root = NULL;
return (0);
}