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/*
* linux/fs/hpfs/super.c
*
* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
*
* mounting, unmounting, error handling
*/
#include <linux/string.h>
#include "hpfs_fn.h"
#include <linux/module.h>
#include <linux/init.h>
/* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */
static void mark_dirty(struct super_block *s)
{
if (s->s_hpfs_chkdsk && !(s->s_flags & MS_RDONLY)) {
struct buffer_head *bh;
struct hpfs_spare_block *sb;
if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
sb->dirty = 1;
sb->old_wrote = 0;
mark_buffer_dirty(bh);
brelse(bh);
}
}
}
/* Mark the filesystem clean (mark it dirty for chkdsk if chkdsk==2 or if there
were errors) */
static void unmark_dirty(struct super_block *s)
{
struct buffer_head *bh;
struct hpfs_spare_block *sb;
if (s->s_flags & MS_RDONLY) return;
if ((sb = hpfs_map_sector(s, 17, &bh, 0))) {
sb->dirty = s->s_hpfs_chkdsk > 1 - s->s_hpfs_was_error;
sb->old_wrote = s->s_hpfs_chkdsk >= 2 && !s->s_hpfs_was_error;
mark_buffer_dirty(bh);
brelse(bh);
}
}
/* Filesystem error... */
#define ERR_BUF_SIZE 1024
void hpfs_error(struct super_block *s, char *m,...)
{
char *buf;
va_list l;
va_start(l, m);
if (!(buf = kmalloc(ERR_BUF_SIZE, GFP_KERNEL)))
printk("HPFS: No memory for error message '%s'\n",m);
else if (vsprintf(buf, m, l) >= ERR_BUF_SIZE)
printk("HPFS: Grrrr... Kernel memory corrupted ... going on, but it'll crash very soon :-(\n");
printk("HPFS: filesystem error: ");
if (buf) printk("%s", buf);
else printk("%s\n",m);
if (!s->s_hpfs_was_error) {
if (s->s_hpfs_err == 2) {
printk("; crashing the system because you wanted it\n");
mark_dirty(s);
panic("HPFS panic");
} else if (s->s_hpfs_err == 1) {
if (s->s_flags & MS_RDONLY) printk("; already mounted read-only\n");
else {
printk("; remounting read-only\n");
mark_dirty(s);
s->s_flags |= MS_RDONLY;
}
} else if (s->s_flags & MS_RDONLY) printk("; going on - but anything won't be destroyed because it's read-only\n");
else printk("; corrupted filesystem mounted read/write - your computer will explode within 20 seconds ... but you wanted it so!\n");
} else printk("\n");
if (buf) kfree(buf);
s->s_hpfs_was_error = 1;
}
/*
* A little trick to detect cycles in many hpfs structures and don't let the
* kernel crash on corrupted filesystem. When first called, set c2 to 0.
*
* BTW. chkdsk doesn't detect cycles correctly. When I had 2 lost directories
* nested each in other, chkdsk locked up happilly.
*/
int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2,
char *msg)
{
if (*c2 && *c1 == key) {
hpfs_error(s, "cycle detected on key %08x in %s", key, msg);
return 1;
}
(*c2)++;
if (!((*c2 - 1) & *c2)) *c1 = key;
return 0;
}
void hpfs_put_super(struct super_block *s)
{
if (s->s_hpfs_cp_table) kfree(s->s_hpfs_cp_table);
if (s->s_hpfs_bmp_dir) kfree(s->s_hpfs_bmp_dir);
unmark_dirty(s);
}
unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno)
{
struct quad_buffer_head qbh;
unsigned *bits;
unsigned i, count;
if (!(bits = hpfs_map_4sectors(s, secno, &qbh, 4))) return 0;
count = 0;
for (i = 0; i < 2048 / sizeof(unsigned); i++) {
unsigned b;
if (!bits[i]) continue;
for (b = bits[i]; b; b>>=1) count += b & 1;
}
hpfs_brelse4(&qbh);
return count;
}
static unsigned count_bitmaps(struct super_block *s)
{
unsigned n, count, n_bands;
n_bands = (s->s_hpfs_fs_size + 0x3fff) >> 14;
count = 0;
for (n = 0; n < n_bands; n++)
count += hpfs_count_one_bitmap(s, s->s_hpfs_bmp_dir[n]);
return count;
}
int hpfs_statfs(struct super_block *s, struct statfs *buf)
{
/*if (s->s_hpfs_n_free == -1) {*/
s->s_hpfs_n_free = count_bitmaps(s);
s->s_hpfs_n_free_dnodes = hpfs_count_one_bitmap(s, s->s_hpfs_dmap);
/*}*/
buf->f_type = s->s_magic;
buf->f_bsize = 512;
buf->f_blocks = s->s_hpfs_fs_size;
buf->f_bfree = s->s_hpfs_n_free;
buf->f_bavail = s->s_hpfs_n_free;
buf->f_files = s->s_hpfs_dirband_size / 4;
buf->f_ffree = s->s_hpfs_n_free_dnodes;
buf->f_namelen = 254;
return 0;
}
/* Super operations */
static struct super_operations hpfs_sops =
{
read_inode: hpfs_read_inode,
delete_inode: hpfs_delete_inode,
put_super: hpfs_put_super,
statfs: hpfs_statfs,
remount_fs: hpfs_remount_fs,
};
/*
* A tiny parser for option strings, stolen from dosfs.
*
* Stolen again from read-only hpfs.
*/
int parse_opts(char *opts, uid_t *uid, gid_t *gid, umode_t *umask,
int *lowercase, int *conv, int *eas, int *chk, int *errs,
int *chkdsk, int *timeshift)
{
char *p, *rhs;
if (!opts)
return 1;
/*printk("Parsing opts: '%s'\n",opts);*/
for (p = strtok(opts, ","); p != 0; p = strtok(0, ",")) {
if ((rhs = strchr(p, '=')) != 0)
*rhs++ = '\0';
if (!strcmp(p, "help")) return 2;
if (!strcmp(p, "uid")) {
if (!rhs || !*rhs)
return 0;
*uid = simple_strtoul(rhs, &rhs, 0);
if (*rhs)
return 0;
}
else if (!strcmp(p, "gid")) {
if (!rhs || !*rhs)
return 0;
*gid = simple_strtoul(rhs, &rhs, 0);
if (*rhs)
return 0;
}
else if (!strcmp(p, "umask")) {
if (!rhs || !*rhs)
return 0;
*umask = simple_strtoul(rhs, &rhs, 8);
if (*rhs)
return 0;
}
else if (!strcmp(p, "timeshift")) {
int m = 1;
if (!rhs || !*rhs)
return 0;
if (*rhs == '-') m = -1;
if (*rhs == '+' || *rhs == '-') rhs++;
*timeshift = simple_strtoul(rhs, &rhs, 0) * m;
if (*rhs)
return 0;
}
else if (!strcmp(p, "case")) {
if (!rhs || !*rhs)
return 0;
if (!strcmp(rhs, "lower"))
*lowercase = 1;
else if (!strcmp(rhs, "asis"))
*lowercase = 0;
else
return 0;
}
else if (!strcmp(p, "conv")) {
if (!rhs || !*rhs)
return 0;
if (!strcmp(rhs, "binary"))
*conv = CONV_BINARY;
else if (!strcmp(rhs, "text"))
*conv = CONV_TEXT;
else if (!strcmp(rhs, "auto"))
*conv = CONV_AUTO;
else
return 0;
}
else if (!strcmp(p, "check")) {
if (!rhs || !*rhs)
return 0;
if (!strcmp(rhs, "none"))
*chk = 0;
else if (!strcmp(rhs, "normal"))
*chk = 1;
else if (!strcmp(rhs, "strict"))
*chk = 2;
else
return 0;
}
else if (!strcmp(p, "errors")) {
if (!rhs || !*rhs)
return 0;
if (!strcmp(rhs, "continue"))
*errs = 0;
else if (!strcmp(rhs, "remount-ro"))
*errs = 1;
else if (!strcmp(rhs, "panic"))
*errs = 2;
else
return 0;
}
else if (!strcmp(p, "eas")) {
if (!rhs || !*rhs)
return 0;
if (!strcmp(rhs, "no"))
*eas = 0;
else if (!strcmp(rhs, "ro"))
*eas = 1;
else if (!strcmp(rhs, "rw"))
*eas = 2;
else
return 0;
}
else if (!strcmp(p, "chkdsk")) {
if (!rhs || !*rhs)
return 0;
if (!strcmp(rhs, "no"))
*chkdsk = 0;
else if (!strcmp(rhs, "errors"))
*chkdsk = 1;
else if (!strcmp(rhs, "always"))
*chkdsk = 2;
else
return 0;
}
else
return 0;
}
return 1;
}
static inline void hpfs_help(void)
{
printk("\n\
HPFS filesystem options:\n\
help do not mount and display this text\n\
uid=xxx set uid of files that don't have uid specified in eas\n\
gid=xxx set gid of files that don't have gid specified in eas\n\
umask=xxx set mode of files that don't have mode specified in eas\n\
case=lower lowercase all files\n\
case=asis do not lowercase files (default)\n\
conv=binary do not convert CR/LF -> LF (default)\n\
conv=auto convert only files with known text extensions\n\
conv=text convert all files\n\
check=none no fs checks - kernel may crash on corrupted filesystem\n\
check=normal do some checks - it should not crash (default)\n\
check=strict do extra time-consuming checks, used for debugging\n\
errors=continue continue on errors\n\
errors=remount-ro remount read-only if errors found (default)\n\
errors=panic panic on errors\n\
chkdsk=no do not mark fs for chkdsking even if there were errors\n\
chkdsk=errors mark fs dirty if errors found (default)\n\
chkdsk=always always mark fs dirty - used for debugging\n\
eas=no ignore extended attributes\n\
eas=ro read but do not write extended attributes\n\
eas=rw r/w eas => enables chmod, chown, mknod, ln -s (default)\n\
timeshift=nnn add nnn seconds to file times\n\
\n");
}
int hpfs_remount_fs(struct super_block *s, int *flags, char *data)
{
uid_t uid;
gid_t gid;
umode_t umask;
int lowercase, conv, eas, chk, errs, chkdsk, timeshift;
int o;
*flags |= MS_NOATIME;
uid = s->s_hpfs_uid; gid = s->s_hpfs_gid;
umask = 0777 & ~s->s_hpfs_mode;
lowercase = s->s_hpfs_lowercase; conv = s->s_hpfs_conv;
eas = s->s_hpfs_eas; chk = s->s_hpfs_chk; chkdsk = s->s_hpfs_chkdsk;
errs = s->s_hpfs_err; timeshift = s->s_hpfs_timeshift;
if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase, &conv,
&eas, &chk, &errs, &chkdsk, ×hift))) {
printk("HPFS: bad mount options.\n");
return 1;
}
if (o == 2) {
hpfs_help();
return 1;
}
if (timeshift != s->s_hpfs_timeshift) {
printk("HPFS: timeshift can't be changed using remount.\n");
return 1;
}
unmark_dirty(s);
s->s_hpfs_uid = uid; s->s_hpfs_gid = gid;
s->s_hpfs_mode = 0777 & ~umask;
s->s_hpfs_lowercase = lowercase; s->s_hpfs_conv = conv;
s->s_hpfs_eas = eas; s->s_hpfs_chk = chk; s->s_hpfs_chkdsk = chkdsk;
s->s_hpfs_err = errs; s->s_hpfs_timeshift = timeshift;
if (!(*flags & MS_RDONLY)) mark_dirty(s);
return 0;
}
struct super_block *hpfs_read_super(struct super_block *s, void *options,
int silent)
{
kdev_t dev;
struct buffer_head *bh0, *bh1, *bh2;
struct hpfs_boot_block *bootblock;
struct hpfs_super_block *superblock;
struct hpfs_spare_block *spareblock;
uid_t uid;
gid_t gid;
umode_t umask;
int lowercase, conv, eas, chk, errs, chkdsk, timeshift;
dnode_secno root_dno;
struct hpfs_dirent *de = NULL;
struct quad_buffer_head qbh;
int o;
s->s_hpfs_bmp_dir = NULL;
s->s_hpfs_cp_table = NULL;
s->s_hpfs_creation_de_lock = s->s_hpfs_rd_inode = 0;
init_waitqueue_head(&s->s_hpfs_creation_de);
init_waitqueue_head(&s->s_hpfs_iget_q);
uid = current->uid;
gid = current->gid;
umask = current->fs->umask;
lowercase = 0;
conv = CONV_BINARY;
eas = 2;
chk = 1;
errs = 1;
chkdsk = 1;
timeshift = 0;
if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase, &conv,
&eas, &chk, &errs, &chkdsk, ×hift))) {
printk("HPFS: bad mount options.\n");
goto bail0;
}
if (o==2) {
hpfs_help();
goto bail0;
}
/*s->s_hpfs_mounting = 1;*/
dev = s->s_dev;
set_blocksize(dev, 512);
s->s_hpfs_fs_size = -1;
if (!(bootblock = hpfs_map_sector(s, 0, &bh0, 0))) goto bail1;
if (!(superblock = hpfs_map_sector(s, 16, &bh1, 1))) goto bail2;
if (!(spareblock = hpfs_map_sector(s, 17, &bh2, 0))) goto bail3;
/* Check magics */
if (/*bootblock->magic != BB_MAGIC
||*/ superblock->magic != SB_MAGIC
|| spareblock->magic != SP_MAGIC) {
if (!silent) printk("HPFS: Bad magic ... probably not HPFS\n");
goto bail4;
}
/* Check version */
if (!(s->s_flags & MS_RDONLY) &&
superblock->funcversion != 2 && superblock->funcversion != 3) {
printk("HPFS: Bad version %d,%d. Mount readonly to go around\n",
(int)superblock->version, (int)superblock->funcversion);
printk("HPFS: please try recent version of HPFS driver at http://artax.karlin.mff.cuni.cz/~mikulas/vyplody/hpfs/index-e.cgi and if it still can't understand this format, contact author - mikulas@artax.karlin.mff.cuni.cz\n");
goto bail4;
}
s->s_flags |= MS_NOATIME;
/* Fill superblock stuff */
s->s_magic = HPFS_SUPER_MAGIC;
s->s_blocksize = 512;
s->s_blocksize_bits = 9;
s->s_op = &hpfs_sops;
s->s_hpfs_root = superblock->root;
s->s_hpfs_fs_size = superblock->n_sectors;
s->s_hpfs_bitmaps = superblock->bitmaps;
s->s_hpfs_dirband_start = superblock->dir_band_start;
s->s_hpfs_dirband_size = superblock->n_dir_band;
s->s_hpfs_dmap = superblock->dir_band_bitmap;
s->s_hpfs_uid = uid;
s->s_hpfs_gid = gid;
s->s_hpfs_mode = 0777 & ~umask;
s->s_hpfs_n_free = -1;
s->s_hpfs_n_free_dnodes = -1;
s->s_hpfs_lowercase = lowercase;
s->s_hpfs_conv = conv;
s->s_hpfs_eas = eas;
s->s_hpfs_chk = chk;
s->s_hpfs_chkdsk = chkdsk;
s->s_hpfs_err = errs;
s->s_hpfs_timeshift = timeshift;
s->s_hpfs_was_error = 0;
s->s_hpfs_cp_table = NULL;
s->s_hpfs_c_bitmap = -1;
/* Load bitmap directory */
if (!(s->s_hpfs_bmp_dir = hpfs_load_bitmap_directory(s, superblock->bitmaps)))
goto bail4;
/* Check for general fs errors*/
if (spareblock->dirty && !spareblock->old_wrote) {
if (errs == 2) {
printk("HPFS: Improperly stopped, not mounted\n");
goto bail4;
}
hpfs_error(s, "improperly stopped");
}
if (!(s->s_flags & MS_RDONLY)) {
spareblock->dirty = 1;
spareblock->old_wrote = 0;
mark_buffer_dirty(bh2);
}
if (spareblock->hotfixes_used || spareblock->n_spares_used) {
if (errs >= 2) {
printk("HPFS: Hotfixes not supported here, try chkdsk\n");
mark_dirty(s);
goto bail4;
}
hpfs_error(s, "hotfixes not supported here, try chkdsk");
if (errs == 0) printk("HPFS: Proceeding, but your filesystem will be probably corrupted by this driver...\n");
else printk("HPFS: This driver may read bad files or crash when operating on disk with hotfixes.\n");
}
if (spareblock->n_dnode_spares != spareblock->n_dnode_spares_free) {
if (errs >= 2) {
printk("HPFS: Spare dnodes used, try chkdsk\n");
mark_dirty(s);
goto bail4;
}
hpfs_error(s, "warning: spare dnodes used, try chkdsk");
if (errs == 0) printk("HPFS: Proceeding, but your filesystem could be corrupted if you delete files or directories\n");
}
if (chk) {
unsigned a;
if (superblock->dir_band_end - superblock->dir_band_start + 1 != superblock->n_dir_band ||
superblock->dir_band_end < superblock->dir_band_start || superblock->n_dir_band > 0x4000) {
hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x",
superblock->dir_band_start, superblock->dir_band_end, superblock->n_dir_band);
goto bail4;
}
a = s->s_hpfs_dirband_size;
s->s_hpfs_dirband_size = 0;
if (hpfs_chk_sectors(s, superblock->dir_band_start, superblock->n_dir_band, "dir_band") ||
hpfs_chk_sectors(s, superblock->dir_band_bitmap, 4, "dir_band_bitmap") ||
hpfs_chk_sectors(s, superblock->bitmaps, 4, "bitmaps")) {
mark_dirty(s);
goto bail4;
}
s->s_hpfs_dirband_size = a;
} else printk("HPFS: You really don't want any checks? You are crazy...\n");
/* Load code page table */
if (spareblock->n_code_pages)
if (!(s->s_hpfs_cp_table = hpfs_load_code_page(s, spareblock->code_page_dir)))
printk("HPFS: Warning: code page support is disabled\n");
brelse(bh2);
brelse(bh1);
brelse(bh0);
hpfs_lock_iget(s, 1);
s->s_root = d_alloc_root(iget(s, s->s_hpfs_root));
hpfs_unlock_iget(s);
if (!s->s_root || !s->s_root->d_inode) {
printk("HPFS: iget failed. Why???\n");
goto bail0;
}
hpfs_set_dentry_operations(s->s_root);
/*
* find the root directory's . pointer & finish filling in the inode
*/
root_dno = hpfs_fnode_dno(s, s->s_hpfs_root);
if (root_dno)
de = map_dirent(s->s_root->d_inode, root_dno, "\001\001", 2, NULL, &qbh);
if (!root_dno || !de) hpfs_error(s, "unable to find root dir");
else {
s->s_root->d_inode->i_atime = local_to_gmt(s, de->read_date);
s->s_root->d_inode->i_mtime = local_to_gmt(s, de->write_date);
s->s_root->d_inode->i_ctime = local_to_gmt(s, de->creation_date);
s->s_root->d_inode->i_hpfs_ea_size = de->ea_size;
s->s_root->d_inode->i_hpfs_parent_dir = s->s_root->d_inode->i_ino;
if (s->s_root->d_inode->i_size == -1) s->s_root->d_inode->i_size = 2048;
if (s->s_root->d_inode->i_blocks == -1) s->s_root->d_inode->i_blocks = 5;
}
if (de) hpfs_brelse4(&qbh);
return s;
bail4: brelse(bh2);
bail3: brelse(bh1);
bail2: brelse(bh0);
bail1:
bail0:
if (s->s_hpfs_bmp_dir) kfree(s->s_hpfs_bmp_dir);
if (s->s_hpfs_cp_table) kfree(s->s_hpfs_cp_table);
return NULL;
}
DECLARE_FSTYPE_DEV(hpfs_fs_type, "hpfs", hpfs_read_super);
static int __init init_hpfs_fs(void)
{
return register_filesystem(&hpfs_fs_type);
}
static void __exit exit_hpfs_fs(void)
{
unregister_filesystem(&hpfs_fs_type);
}
EXPORT_NO_SYMBOLS;
module_init(init_hpfs_fs)
module_exit(exit_hpfs_fs)
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