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/*
* linux/fs/ext2/super.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/fs/minix/inode.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* Big-endian to little-endian byte-swapping/bitmaps by
* David S. Miller (davem@caip.rutgers.edu), 1995
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/ext2_fs.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/locks.h>
#include <linux/blkdev.h>
#include <asm/uaccess.h>
static void ext2_sync_super(struct super_block *sb,
struct ext2_super_block *es);
static char error_buf[1024];
void ext2_error (struct super_block * sb, const char * function,
const char * fmt, ...)
{
va_list args;
struct ext2_super_block *es = EXT2_SB(sb)->s_es;
if (!(sb->s_flags & MS_RDONLY)) {
sb->u.ext2_sb.s_mount_state |= EXT2_ERROR_FS;
es->s_state =
cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS);
ext2_sync_super(sb, es);
}
va_start (args, fmt);
vsprintf (error_buf, fmt, args);
va_end (args);
if (test_opt (sb, ERRORS_PANIC) ||
(le16_to_cpu(sb->u.ext2_sb.s_es->s_errors) == EXT2_ERRORS_PANIC &&
!test_opt (sb, ERRORS_CONT) && !test_opt (sb, ERRORS_RO)))
panic ("EXT2-fs panic (device %s): %s: %s\n",
bdevname(sb->s_dev), function, error_buf);
printk (KERN_CRIT "EXT2-fs error (device %s): %s: %s\n",
bdevname(sb->s_dev), function, error_buf);
if (test_opt (sb, ERRORS_RO) ||
(le16_to_cpu(sb->u.ext2_sb.s_es->s_errors) == EXT2_ERRORS_RO &&
!test_opt (sb, ERRORS_CONT) && !test_opt (sb, ERRORS_PANIC))) {
printk ("Remounting filesystem read-only\n");
sb->s_flags |= MS_RDONLY;
}
}
NORET_TYPE void ext2_panic (struct super_block * sb, const char * function,
const char * fmt, ...)
{
va_list args;
if (!(sb->s_flags & MS_RDONLY)) {
sb->u.ext2_sb.s_mount_state |= EXT2_ERROR_FS;
sb->u.ext2_sb.s_es->s_state =
cpu_to_le16(le16_to_cpu(sb->u.ext2_sb.s_es->s_state) | EXT2_ERROR_FS);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh);
sb->s_dirt = 1;
}
va_start (args, fmt);
vsprintf (error_buf, fmt, args);
va_end (args);
sb->s_flags |= MS_RDONLY;
panic ("EXT2-fs panic (device %s): %s: %s\n",
bdevname(sb->s_dev), function, error_buf);
}
void ext2_warning (struct super_block * sb, const char * function,
const char * fmt, ...)
{
va_list args;
va_start (args, fmt);
vsprintf (error_buf, fmt, args);
va_end (args);
printk (KERN_WARNING "EXT2-fs warning (device %s): %s: %s\n",
bdevname(sb->s_dev), function, error_buf);
}
void ext2_update_dynamic_rev(struct super_block *sb)
{
struct ext2_super_block *es = EXT2_SB(sb)->s_es;
if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
return;
ext2_warning(sb, __FUNCTION__,
"updating to rev %d because of new feature flag, "
"running e2fsck is recommended",
EXT2_DYNAMIC_REV);
es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
/* leave es->s_feature_*compat flags alone */
/* es->s_uuid will be set by e2fsck if empty */
/*
* The rest of the superblock fields should be zero, and if not it
* means they are likely already in use, so leave them alone. We
* can leave it up to e2fsck to clean up any inconsistencies there.
*/
}
void ext2_put_super (struct super_block * sb)
{
int db_count;
int i;
if (!(sb->s_flags & MS_RDONLY)) {
struct ext2_super_block *es = EXT2_SB(sb)->s_es;
es->s_state = le16_to_cpu(EXT2_SB(sb)->s_mount_state);
ext2_sync_super(sb, es);
}
db_count = EXT2_SB(sb)->s_gdb_count;
for (i = 0; i < db_count; i++)
if (sb->u.ext2_sb.s_group_desc[i])
brelse (sb->u.ext2_sb.s_group_desc[i]);
kfree(sb->u.ext2_sb.s_group_desc);
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
if (sb->u.ext2_sb.s_inode_bitmap[i])
brelse (sb->u.ext2_sb.s_inode_bitmap[i]);
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
if (sb->u.ext2_sb.s_block_bitmap[i])
brelse (sb->u.ext2_sb.s_block_bitmap[i]);
brelse (sb->u.ext2_sb.s_sbh);
return;
}
static struct super_operations ext2_sops = {
read_inode: ext2_read_inode,
write_inode: ext2_write_inode,
put_inode: ext2_put_inode,
delete_inode: ext2_delete_inode,
put_super: ext2_put_super,
write_super: ext2_write_super,
statfs: ext2_statfs,
remount_fs: ext2_remount,
};
/*
* This function has been shamelessly adapted from the msdos fs
*/
static int parse_options (char * options, unsigned long * sb_block,
unsigned short *resuid, unsigned short * resgid,
unsigned long * mount_options)
{
char * this_char;
char * value;
if (!options)
return 1;
for (this_char = strtok (options, ",");
this_char != NULL;
this_char = strtok (NULL, ",")) {
if ((value = strchr (this_char, '=')) != NULL)
*value++ = 0;
if (!strcmp (this_char, "bsddf"))
clear_opt (*mount_options, MINIX_DF);
else if (!strcmp (this_char, "nouid32")) {
set_opt (*mount_options, NO_UID32);
}
else if (!strcmp (this_char, "check")) {
if (!value || !*value || !strcmp (value, "none"))
clear_opt (*mount_options, CHECK);
else
#ifdef CONFIG_EXT2_CHECK
set_opt (*mount_options, CHECK);
#else
printk("EXT2 Check option not supported\n");
#endif
}
else if (!strcmp (this_char, "debug"))
set_opt (*mount_options, DEBUG);
else if (!strcmp (this_char, "errors")) {
if (!value || !*value) {
printk ("EXT2-fs: the errors option requires "
"an argument\n");
return 0;
}
if (!strcmp (value, "continue")) {
clear_opt (*mount_options, ERRORS_RO);
clear_opt (*mount_options, ERRORS_PANIC);
set_opt (*mount_options, ERRORS_CONT);
}
else if (!strcmp (value, "remount-ro")) {
clear_opt (*mount_options, ERRORS_CONT);
clear_opt (*mount_options, ERRORS_PANIC);
set_opt (*mount_options, ERRORS_RO);
}
else if (!strcmp (value, "panic")) {
clear_opt (*mount_options, ERRORS_CONT);
clear_opt (*mount_options, ERRORS_RO);
set_opt (*mount_options, ERRORS_PANIC);
}
else {
printk ("EXT2-fs: Invalid errors option: %s\n",
value);
return 0;
}
}
else if (!strcmp (this_char, "grpid") ||
!strcmp (this_char, "bsdgroups"))
set_opt (*mount_options, GRPID);
else if (!strcmp (this_char, "minixdf"))
set_opt (*mount_options, MINIX_DF);
else if (!strcmp (this_char, "nocheck"))
clear_opt (*mount_options, CHECK);
else if (!strcmp (this_char, "nogrpid") ||
!strcmp (this_char, "sysvgroups"))
clear_opt (*mount_options, GRPID);
else if (!strcmp (this_char, "resgid")) {
if (!value || !*value) {
printk ("EXT2-fs: the resgid option requires "
"an argument\n");
return 0;
}
*resgid = simple_strtoul (value, &value, 0);
if (*value) {
printk ("EXT2-fs: Invalid resgid option: %s\n",
value);
return 0;
}
}
else if (!strcmp (this_char, "resuid")) {
if (!value || !*value) {
printk ("EXT2-fs: the resuid option requires "
"an argument");
return 0;
}
*resuid = simple_strtoul (value, &value, 0);
if (*value) {
printk ("EXT2-fs: Invalid resuid option: %s\n",
value);
return 0;
}
}
else if (!strcmp (this_char, "sb")) {
if (!value || !*value) {
printk ("EXT2-fs: the sb option requires "
"an argument");
return 0;
}
*sb_block = simple_strtoul (value, &value, 0);
if (*value) {
printk ("EXT2-fs: Invalid sb option: %s\n",
value);
return 0;
}
}
/* Silently ignore the quota options */
else if (!strcmp (this_char, "grpquota")
|| !strcmp (this_char, "noquota")
|| !strcmp (this_char, "quota")
|| !strcmp (this_char, "usrquota"))
/* Don't do anything ;-) */ ;
else {
printk ("EXT2-fs: Unrecognized mount option %s\n", this_char);
return 0;
}
}
return 1;
}
static int ext2_setup_super (struct super_block * sb,
struct ext2_super_block * es,
int read_only)
{
int res = 0;
if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
printk ("EXT2-fs warning: revision level too high, "
"forcing read-only mode\n");
res = MS_RDONLY;
}
if (read_only)
return res;
if (!(sb->u.ext2_sb.s_mount_state & EXT2_VALID_FS))
printk ("EXT2-fs warning: mounting unchecked fs, "
"running e2fsck is recommended\n");
else if ((sb->u.ext2_sb.s_mount_state & EXT2_ERROR_FS))
printk ("EXT2-fs warning: mounting fs with errors, "
"running e2fsck is recommended\n");
else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
le16_to_cpu(es->s_mnt_count) >=
(unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
printk ("EXT2-fs warning: maximal mount count reached, "
"running e2fsck is recommended\n");
else if (le32_to_cpu(es->s_checkinterval) &&
(le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= CURRENT_TIME))
printk ("EXT2-fs warning: checktime reached, "
"running e2fsck is recommended\n");
if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
es->s_max_mnt_count = (__s16) cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
ext2_write_super(sb);
if (test_opt (sb, DEBUG))
printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
"bpg=%lu, ipg=%lu, mo=%04lx]\n",
EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
sb->u.ext2_sb.s_frag_size,
sb->u.ext2_sb.s_groups_count,
EXT2_BLOCKS_PER_GROUP(sb),
EXT2_INODES_PER_GROUP(sb),
sb->u.ext2_sb.s_mount_opt);
#ifdef CONFIG_EXT2_CHECK
if (test_opt (sb, CHECK)) {
ext2_check_blocks_bitmap (sb);
ext2_check_inodes_bitmap (sb);
}
#endif
return res;
}
static int ext2_check_descriptors (struct super_block * sb)
{
int i;
int desc_block = 0;
unsigned long block = le32_to_cpu(sb->u.ext2_sb.s_es->s_first_data_block);
struct ext2_group_desc * gdp = NULL;
ext2_debug ("Checking group descriptors");
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++)
{
if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
gdp = (struct ext2_group_desc *) sb->u.ext2_sb.s_group_desc[desc_block++]->b_data;
if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Block bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Inode bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
return 0;
}
if (le32_to_cpu(gdp->bg_inode_table) < block ||
le32_to_cpu(gdp->bg_inode_table) + sb->u.ext2_sb.s_itb_per_group >=
block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Inode table for group %d"
" not in group (block %lu)!",
i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
return 0;
}
block += EXT2_BLOCKS_PER_GROUP(sb);
gdp++;
}
return 1;
}
#define log2(n) ffz(~(n))
/*
* Maximal file size. There is a direct, and {,double-,triple-}indirect
* block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
* We need to be 1 filesystem block less than the 2^32 sector limit.
*/
static loff_t ext2_max_size(int bits)
{
loff_t res = EXT2_NDIR_BLOCKS;
res += 1LL << (bits-2);
res += 1LL << (2*(bits-2));
res += 1LL << (3*(bits-2));
res <<= bits;
if (res > (512LL << 32) - (1 << bits))
res = (512LL << 32) - (1 << bits);
return res;
}
struct super_block * ext2_read_super (struct super_block * sb, void * data,
int silent)
{
struct buffer_head * bh;
struct ext2_super_block * es;
unsigned long sb_block = 1;
unsigned short resuid = EXT2_DEF_RESUID;
unsigned short resgid = EXT2_DEF_RESGID;
unsigned long logic_sb_block = 1;
unsigned long offset = 0;
kdev_t dev = sb->s_dev;
int blocksize = BLOCK_SIZE;
int db_count;
int i, j;
/*
* See what the current blocksize for the device is, and
* use that as the blocksize. Otherwise (or if the blocksize
* is smaller than the default) use the default.
* This is important for devices that have a hardware
* sectorsize that is larger than the default.
*/
blocksize = get_hardsect_size(dev);
if(blocksize < BLOCK_SIZE )
blocksize = BLOCK_SIZE;
sb->u.ext2_sb.s_mount_opt = 0;
if (!parse_options ((char *) data, &sb_block, &resuid, &resgid,
&sb->u.ext2_sb.s_mount_opt)) {
return NULL;
}
if (set_blocksize(dev, blocksize) < 0) {
printk ("EXT2-fs: unable to set blocksize %d\n", blocksize);
return NULL;
}
sb->s_blocksize = blocksize;
/*
* If the superblock doesn't start on a sector boundary,
* calculate the offset. FIXME(eric) this doesn't make sense
* that we would have to do this.
*/
if (blocksize != BLOCK_SIZE) {
logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
offset = (sb_block*BLOCK_SIZE) % blocksize;
}
if (!(bh = sb_bread(sb, logic_sb_block))) {
printk ("EXT2-fs: unable to read superblock\n");
return NULL;
}
/*
* Note: s_es must be initialized as soon as possible because
* some ext2 macro-instructions depend on its value
*/
es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
sb->u.ext2_sb.s_es = es;
sb->s_magic = le16_to_cpu(es->s_magic);
if (sb->s_magic != EXT2_SUPER_MAGIC) {
if (!silent)
printk ("VFS: Can't find ext2 filesystem on dev %s.\n",
bdevname(dev));
goto failed_mount;
}
if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
(EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
printk("EXT2-fs warning: feature flags set on rev 0 fs, "
"running e2fsck is recommended\n");
/*
* Check feature flags regardless of the revision level, since we
* previously didn't change the revision level when setting the flags,
* so there is a chance incompat flags are set on a rev 0 filesystem.
*/
if ((i = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))) {
printk("EXT2-fs: %s: couldn't mount because of "
"unsupported optional features (%x).\n",
bdevname(dev), i);
goto failed_mount;
}
if (!(sb->s_flags & MS_RDONLY) &&
(i = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
printk("EXT2-fs: %s: couldn't mount RDWR because of "
"unsupported optional features (%x).\n",
bdevname(dev), i);
goto failed_mount;
}
sb->s_blocksize_bits =
le32_to_cpu(EXT2_SB(sb)->s_es->s_log_block_size) + 10;
sb->s_blocksize = 1 << sb->s_blocksize_bits;
sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
/* If the blocksize doesn't match, re-read the thing.. */
if (sb->s_blocksize != blocksize) {
blocksize = sb->s_blocksize;
brelse(bh);
if (set_blocksize(dev, blocksize) < 0) {
printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
return NULL;
}
logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
offset = (sb_block*BLOCK_SIZE) % blocksize;
bh = sb_bread(sb, logic_sb_block);
if(!bh) {
printk("EXT2-fs: Couldn't read superblock on "
"2nd try.\n");
goto failed_mount;
}
es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
sb->u.ext2_sb.s_es = es;
if (es->s_magic != le16_to_cpu(EXT2_SUPER_MAGIC)) {
printk ("EXT2-fs: Magic mismatch, very weird !\n");
goto failed_mount;
}
}
if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
sb->u.ext2_sb.s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
sb->u.ext2_sb.s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
} else {
sb->u.ext2_sb.s_inode_size = le16_to_cpu(es->s_inode_size);
sb->u.ext2_sb.s_first_ino = le32_to_cpu(es->s_first_ino);
if (sb->u.ext2_sb.s_inode_size != EXT2_GOOD_OLD_INODE_SIZE) {
printk ("EXT2-fs: unsupported inode size: %d\n",
sb->u.ext2_sb.s_inode_size);
goto failed_mount;
}
}
sb->u.ext2_sb.s_frag_size = EXT2_MIN_FRAG_SIZE <<
le32_to_cpu(es->s_log_frag_size);
if (sb->u.ext2_sb.s_frag_size)
sb->u.ext2_sb.s_frags_per_block = sb->s_blocksize /
sb->u.ext2_sb.s_frag_size;
else
sb->s_magic = 0;
sb->u.ext2_sb.s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
sb->u.ext2_sb.s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
sb->u.ext2_sb.s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
sb->u.ext2_sb.s_inodes_per_block = sb->s_blocksize /
EXT2_INODE_SIZE(sb);
sb->u.ext2_sb.s_itb_per_group = sb->u.ext2_sb.s_inodes_per_group /
sb->u.ext2_sb.s_inodes_per_block;
sb->u.ext2_sb.s_desc_per_block = sb->s_blocksize /
sizeof (struct ext2_group_desc);
sb->u.ext2_sb.s_sbh = bh;
if (resuid != EXT2_DEF_RESUID)
sb->u.ext2_sb.s_resuid = resuid;
else
sb->u.ext2_sb.s_resuid = le16_to_cpu(es->s_def_resuid);
if (resgid != EXT2_DEF_RESGID)
sb->u.ext2_sb.s_resgid = resgid;
else
sb->u.ext2_sb.s_resgid = le16_to_cpu(es->s_def_resgid);
sb->u.ext2_sb.s_mount_state = le16_to_cpu(es->s_state);
sb->u.ext2_sb.s_addr_per_block_bits =
log2 (EXT2_ADDR_PER_BLOCK(sb));
sb->u.ext2_sb.s_desc_per_block_bits =
log2 (EXT2_DESC_PER_BLOCK(sb));
if (sb->s_magic != EXT2_SUPER_MAGIC) {
if (!silent)
printk ("VFS: Can't find an ext2 filesystem on dev "
"%s.\n",
bdevname(dev));
goto failed_mount;
}
if (sb->s_blocksize != bh->b_size) {
if (!silent)
printk ("VFS: Unsupported blocksize on dev "
"%s.\n", bdevname(dev));
goto failed_mount;
}
if (sb->s_blocksize != sb->u.ext2_sb.s_frag_size) {
printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
sb->u.ext2_sb.s_frag_size, sb->s_blocksize);
goto failed_mount;
}
if (sb->u.ext2_sb.s_blocks_per_group > sb->s_blocksize * 8) {
printk ("EXT2-fs: #blocks per group too big: %lu\n",
sb->u.ext2_sb.s_blocks_per_group);
goto failed_mount;
}
if (sb->u.ext2_sb.s_frags_per_group > sb->s_blocksize * 8) {
printk ("EXT2-fs: #fragments per group too big: %lu\n",
sb->u.ext2_sb.s_frags_per_group);
goto failed_mount;
}
if (sb->u.ext2_sb.s_inodes_per_group > sb->s_blocksize * 8) {
printk ("EXT2-fs: #inodes per group too big: %lu\n",
sb->u.ext2_sb.s_inodes_per_group);
goto failed_mount;
}
sb->u.ext2_sb.s_groups_count = (le32_to_cpu(es->s_blocks_count) -
le32_to_cpu(es->s_first_data_block) +
EXT2_BLOCKS_PER_GROUP(sb) - 1) /
EXT2_BLOCKS_PER_GROUP(sb);
db_count = (sb->u.ext2_sb.s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
EXT2_DESC_PER_BLOCK(sb);
sb->u.ext2_sb.s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
if (sb->u.ext2_sb.s_group_desc == NULL) {
printk ("EXT2-fs: not enough memory\n");
goto failed_mount;
}
for (i = 0; i < db_count; i++) {
sb->u.ext2_sb.s_group_desc[i] = sb_bread(sb, logic_sb_block + i + 1);
if (!sb->u.ext2_sb.s_group_desc[i]) {
for (j = 0; j < i; j++)
brelse (sb->u.ext2_sb.s_group_desc[j]);
kfree(sb->u.ext2_sb.s_group_desc);
printk ("EXT2-fs: unable to read group descriptors\n");
goto failed_mount;
}
}
if (!ext2_check_descriptors (sb)) {
printk ("EXT2-fs: group descriptors corrupted!\n");
db_count = i;
goto failed_mount2;
}
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++) {
sb->u.ext2_sb.s_inode_bitmap_number[i] = 0;
sb->u.ext2_sb.s_inode_bitmap[i] = NULL;
sb->u.ext2_sb.s_block_bitmap_number[i] = 0;
sb->u.ext2_sb.s_block_bitmap[i] = NULL;
}
sb->u.ext2_sb.s_loaded_inode_bitmaps = 0;
sb->u.ext2_sb.s_loaded_block_bitmaps = 0;
sb->u.ext2_sb.s_gdb_count = db_count;
/*
* set up enough so that it can read an inode
*/
sb->s_op = &ext2_sops;
sb->s_root = d_alloc_root(iget(sb, EXT2_ROOT_INO));
if (!sb->s_root || !S_ISDIR(sb->s_root->d_inode->i_mode) ||
!sb->s_root->d_inode->i_blocks || !sb->s_root->d_inode->i_size) {
if (sb->s_root) {
dput(sb->s_root);
sb->s_root = NULL;
printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
} else
printk(KERN_ERR "EXT2-fs: get root inode failed\n");
goto failed_mount2;
}
ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
return sb;
failed_mount2:
for (i = 0; i < db_count; i++)
brelse(sb->u.ext2_sb.s_group_desc[i]);
kfree(sb->u.ext2_sb.s_group_desc);
failed_mount:
brelse(bh);
return NULL;
}
static void ext2_commit_super (struct super_block * sb,
struct ext2_super_block * es)
{
es->s_wtime = cpu_to_le32(CURRENT_TIME);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh);
sb->s_dirt = 0;
}
static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
{
es->s_wtime = cpu_to_le32(CURRENT_TIME);
mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
ll_rw_block(WRITE, 1, &EXT2_SB(sb)->s_sbh);
wait_on_buffer(EXT2_SB(sb)->s_sbh);
sb->s_dirt = 0;
}
/*
* In the second extended file system, it is not necessary to
* write the super block since we use a mapping of the
* disk super block in a buffer.
*
* However, this function is still used to set the fs valid
* flags to 0. We need to set this flag to 0 since the fs
* may have been checked while mounted and e2fsck may have
* set s_state to EXT2_VALID_FS after some corrections.
*/
void ext2_write_super (struct super_block * sb)
{
struct ext2_super_block * es;
if (!(sb->s_flags & MS_RDONLY)) {
es = sb->u.ext2_sb.s_es;
if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
ext2_debug ("setting valid to 0\n");
es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
~EXT2_VALID_FS);
es->s_mtime = cpu_to_le32(CURRENT_TIME);
ext2_sync_super(sb, es);
} else
ext2_commit_super (sb, es);
}
sb->s_dirt = 0;
}
int ext2_remount (struct super_block * sb, int * flags, char * data)
{
struct ext2_super_block * es;
unsigned short resuid = sb->u.ext2_sb.s_resuid;
unsigned short resgid = sb->u.ext2_sb.s_resgid;
unsigned long new_mount_opt;
unsigned long tmp;
/*
* Allow the "check" option to be passed as a remount option.
*/
new_mount_opt = sb->u.ext2_sb.s_mount_opt;
if (!parse_options (data, &tmp, &resuid, &resgid,
&new_mount_opt))
return -EINVAL;
sb->u.ext2_sb.s_mount_opt = new_mount_opt;
sb->u.ext2_sb.s_resuid = resuid;
sb->u.ext2_sb.s_resgid = resgid;
es = sb->u.ext2_sb.s_es;
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (*flags & MS_RDONLY) {
if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
!(sb->u.ext2_sb.s_mount_state & EXT2_VALID_FS))
return 0;
/*
* OK, we are remounting a valid rw partition rdonly, so set
* the rdonly flag and then mark the partition as valid again.
*/
es->s_state = cpu_to_le16(sb->u.ext2_sb.s_mount_state);
es->s_mtime = cpu_to_le32(CURRENT_TIME);
} else {
int ret;
if ((ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
~EXT2_FEATURE_RO_COMPAT_SUPP))) {
printk("EXT2-fs: %s: couldn't remount RDWR because of "
"unsupported optional features (%x).\n",
bdevname(sb->s_dev), ret);
return -EROFS;
}
/*
* Mounting a RDONLY partition read-write, so reread and
* store the current valid flag. (It may have been changed
* by e2fsck since we originally mounted the partition.)
*/
sb->u.ext2_sb.s_mount_state = le16_to_cpu(es->s_state);
if (!ext2_setup_super (sb, es, 0))
sb->s_flags &= ~MS_RDONLY;
}
ext2_sync_super(sb, es);
return 0;
}
int ext2_statfs (struct super_block * sb, struct statfs * buf)
{
unsigned long overhead;
int i;
if (test_opt (sb, MINIX_DF))
overhead = 0;
else {
/*
* Compute the overhead (FS structures)
*/
/*
* All of the blocks before first_data_block are
* overhead
*/
overhead = le32_to_cpu(sb->u.ext2_sb.s_es->s_first_data_block);
/*
* Add the overhead attributed to the superblock and
* block group descriptors. If the sparse superblocks
* feature is turned on, then not all groups have this.
*/
for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++)
overhead += ext2_bg_has_super(sb, i) +
ext2_bg_num_gdb(sb, i);
/*
* Every block group has an inode bitmap, a block
* bitmap, and an inode table.
*/
overhead += (sb->u.ext2_sb.s_groups_count *
(2 + sb->u.ext2_sb.s_itb_per_group));
}
buf->f_type = EXT2_SUPER_MAGIC;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = le32_to_cpu(sb->u.ext2_sb.s_es->s_blocks_count) - overhead;
buf->f_bfree = ext2_count_free_blocks (sb);
buf->f_bavail = buf->f_bfree - le32_to_cpu(sb->u.ext2_sb.s_es->s_r_blocks_count);
if (buf->f_bfree < le32_to_cpu(sb->u.ext2_sb.s_es->s_r_blocks_count))
buf->f_bavail = 0;
buf->f_files = le32_to_cpu(sb->u.ext2_sb.s_es->s_inodes_count);
buf->f_ffree = ext2_count_free_inodes (sb);
buf->f_namelen = EXT2_NAME_LEN;
return 0;
}
static DECLARE_FSTYPE_DEV(ext2_fs_type, "ext2", ext2_read_super);
static int __init init_ext2_fs(void)
{
return register_filesystem(&ext2_fs_type);
}
static void __exit exit_ext2_fs(void)
{
unregister_filesystem(&ext2_fs_type);
}
EXPORT_NO_SYMBOLS;
module_init(init_ext2_fs)
module_exit(exit_ext2_fs)
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