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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/fs/isofs/inode.c

1598 строки
40 KiB
C
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/*
* linux/fs/isofs/inode.c
*
* (C) 1991 Linus Torvalds - minix filesystem
* 1992, 1993, 1994 Eric Youngdale Modified for ISO 9660 filesystem.
* 1994 Eberhard Mönkeberg - multi session handling.
* 1995 Mark Dobie - allow mounting of some weird VideoCDs and PhotoCDs.
* 1997 Gordon Chaffee - Joliet CDs
* 1998 Eric Lammerts - ISO 9660 Level 3
* 2004 Paul Serice - Inode Support pushed out from 4GB to 128GB
* 2004 Paul Serice - NFS Export Operations
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/nls.h>
#include <linux/ctype.h>
#include <linux/statfs.h>
#include <linux/cdrom.h>
#include <linux/parser.h>
#include <linux/mpage.h>
#include <linux/user_namespace.h>
#include "isofs.h"
#include "zisofs.h"
#define BEQUIET
static int isofs_hashi(const struct dentry *parent, const struct inode *inode,
struct qstr *qstr);
static int isofs_hash(const struct dentry *parent, const struct inode *inode,
struct qstr *qstr);
static int isofs_dentry_cmpi(const struct dentry *parent,
const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name);
static int isofs_dentry_cmp(const struct dentry *parent,
const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name);
#ifdef CONFIG_JOLIET
static int isofs_hashi_ms(const struct dentry *parent, const struct inode *inode,
struct qstr *qstr);
static int isofs_hash_ms(const struct dentry *parent, const struct inode *inode,
struct qstr *qstr);
static int isofs_dentry_cmpi_ms(const struct dentry *parent,
const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name);
static int isofs_dentry_cmp_ms(const struct dentry *parent,
const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name);
#endif
static void isofs_put_super(struct super_block *sb)
{
struct isofs_sb_info *sbi = ISOFS_SB(sb);
#ifdef CONFIG_JOLIET
unload_nls(sbi->s_nls_iocharset);
#endif
kfree(sbi);
sb->s_fs_info = NULL;
return;
}
static int isofs_read_inode(struct inode *);
static int isofs_statfs (struct dentry *, struct kstatfs *);
static struct kmem_cache *isofs_inode_cachep;
static struct inode *isofs_alloc_inode(struct super_block *sb)
{
struct iso_inode_info *ei;
ei = kmem_cache_alloc(isofs_inode_cachep, GFP_KERNEL);
if (!ei)
return NULL;
return &ei->vfs_inode;
}
static void isofs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(isofs_inode_cachep, ISOFS_I(inode));
}
static void isofs_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, isofs_i_callback);
}
static void init_once(void *foo)
{
struct iso_inode_info *ei = foo;
inode_init_once(&ei->vfs_inode);
}
static int init_inodecache(void)
{
isofs_inode_cachep = kmem_cache_create("isofs_inode_cache",
sizeof(struct iso_inode_info),
0, (SLAB_RECLAIM_ACCOUNT|
SLAB_MEM_SPREAD),
init_once);
if (isofs_inode_cachep == NULL)
return -ENOMEM;
return 0;
}
static void destroy_inodecache(void)
{
/*
* Make sure all delayed rcu free inodes are flushed before we
* destroy cache.
*/
rcu_barrier();
kmem_cache_destroy(isofs_inode_cachep);
}
static int isofs_remount(struct super_block *sb, int *flags, char *data)
{
/* we probably want a lot more here */
*flags |= MS_RDONLY;
return 0;
}
static const struct super_operations isofs_sops = {
.alloc_inode = isofs_alloc_inode,
.destroy_inode = isofs_destroy_inode,
.put_super = isofs_put_super,
.statfs = isofs_statfs,
.remount_fs = isofs_remount,
.show_options = generic_show_options,
};
static const struct dentry_operations isofs_dentry_ops[] = {
{
.d_hash = isofs_hash,
.d_compare = isofs_dentry_cmp,
},
{
.d_hash = isofs_hashi,
.d_compare = isofs_dentry_cmpi,
},
#ifdef CONFIG_JOLIET
{
.d_hash = isofs_hash_ms,
.d_compare = isofs_dentry_cmp_ms,
},
{
.d_hash = isofs_hashi_ms,
.d_compare = isofs_dentry_cmpi_ms,
},
#endif
};
struct iso9660_options{
unsigned int rock:1;
unsigned int joliet:1;
unsigned int cruft:1;
unsigned int hide:1;
unsigned int showassoc:1;
unsigned int nocompress:1;
unsigned int overriderockperm:1;
unsigned int uid_set:1;
unsigned int gid_set:1;
unsigned int utf8:1;
unsigned char map;
unsigned char check;
unsigned int blocksize;
umode_t fmode;
umode_t dmode;
kgid_t gid;
kuid_t uid;
char *iocharset;
/* LVE */
s32 session;
s32 sbsector;
};
/*
* Compute the hash for the isofs name corresponding to the dentry.
*/
static int
isofs_hash_common(const struct dentry *dentry, struct qstr *qstr, int ms)
{
const char *name;
int len;
len = qstr->len;
name = qstr->name;
if (ms) {
while (len && name[len-1] == '.')
len--;
}
qstr->hash = full_name_hash(name, len);
return 0;
}
/*
* Compute the hash for the isofs name corresponding to the dentry.
*/
static int
isofs_hashi_common(const struct dentry *dentry, struct qstr *qstr, int ms)
{
const char *name;
int len;
char c;
unsigned long hash;
len = qstr->len;
name = qstr->name;
if (ms) {
while (len && name[len-1] == '.')
len--;
}
hash = init_name_hash();
while (len--) {
c = tolower(*name++);
hash = partial_name_hash(c, hash);
}
qstr->hash = end_name_hash(hash);
return 0;
}
/*
* Compare of two isofs names.
*/
static int isofs_dentry_cmp_common(
unsigned int len, const char *str,
const struct qstr *name, int ms, int ci)
{
int alen, blen;
/* A filename cannot end in '.' or we treat it like it has none */
alen = name->len;
blen = len;
if (ms) {
while (alen && name->name[alen-1] == '.')
alen--;
while (blen && str[blen-1] == '.')
blen--;
}
if (alen == blen) {
if (ci) {
if (strnicmp(name->name, str, alen) == 0)
return 0;
} else {
if (strncmp(name->name, str, alen) == 0)
return 0;
}
}
return 1;
}
static int
isofs_hash(const struct dentry *dentry, const struct inode *inode,
struct qstr *qstr)
{
return isofs_hash_common(dentry, qstr, 0);
}
static int
isofs_hashi(const struct dentry *dentry, const struct inode *inode,
struct qstr *qstr)
{
return isofs_hashi_common(dentry, qstr, 0);
}
static int
isofs_dentry_cmp(const struct dentry *parent, const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name)
{
return isofs_dentry_cmp_common(len, str, name, 0, 0);
}
static int
isofs_dentry_cmpi(const struct dentry *parent, const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name)
{
return isofs_dentry_cmp_common(len, str, name, 0, 1);
}
#ifdef CONFIG_JOLIET
static int
isofs_hash_ms(const struct dentry *dentry, const struct inode *inode,
struct qstr *qstr)
{
return isofs_hash_common(dentry, qstr, 1);
}
static int
isofs_hashi_ms(const struct dentry *dentry, const struct inode *inode,
struct qstr *qstr)
{
return isofs_hashi_common(dentry, qstr, 1);
}
static int
isofs_dentry_cmp_ms(const struct dentry *parent, const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name)
{
return isofs_dentry_cmp_common(len, str, name, 1, 0);
}
static int
isofs_dentry_cmpi_ms(const struct dentry *parent, const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name)
{
return isofs_dentry_cmp_common(len, str, name, 1, 1);
}
#endif
enum {
Opt_block, Opt_check_r, Opt_check_s, Opt_cruft, Opt_gid, Opt_ignore,
Opt_iocharset, Opt_map_a, Opt_map_n, Opt_map_o, Opt_mode, Opt_nojoliet,
Opt_norock, Opt_sb, Opt_session, Opt_uid, Opt_unhide, Opt_utf8, Opt_err,
Opt_nocompress, Opt_hide, Opt_showassoc, Opt_dmode, Opt_overriderockperm,
};
static const match_table_t tokens = {
{Opt_norock, "norock"},
{Opt_nojoliet, "nojoliet"},
{Opt_unhide, "unhide"},
{Opt_hide, "hide"},
{Opt_showassoc, "showassoc"},
{Opt_cruft, "cruft"},
{Opt_utf8, "utf8"},
{Opt_iocharset, "iocharset=%s"},
{Opt_map_a, "map=acorn"},
{Opt_map_a, "map=a"},
{Opt_map_n, "map=normal"},
{Opt_map_n, "map=n"},
{Opt_map_o, "map=off"},
{Opt_map_o, "map=o"},
{Opt_session, "session=%u"},
{Opt_sb, "sbsector=%u"},
{Opt_check_r, "check=relaxed"},
{Opt_check_r, "check=r"},
{Opt_check_s, "check=strict"},
{Opt_check_s, "check=s"},
{Opt_uid, "uid=%u"},
{Opt_gid, "gid=%u"},
{Opt_mode, "mode=%u"},
{Opt_dmode, "dmode=%u"},
{Opt_overriderockperm, "overriderockperm"},
{Opt_block, "block=%u"},
{Opt_ignore, "conv=binary"},
{Opt_ignore, "conv=b"},
{Opt_ignore, "conv=text"},
{Opt_ignore, "conv=t"},
{Opt_ignore, "conv=mtext"},
{Opt_ignore, "conv=m"},
{Opt_ignore, "conv=auto"},
{Opt_ignore, "conv=a"},
{Opt_nocompress, "nocompress"},
{Opt_err, NULL}
};
static int parse_options(char *options, struct iso9660_options *popt)
{
char *p;
int option;
popt->map = 'n';
popt->rock = 1;
popt->joliet = 1;
popt->cruft = 0;
popt->hide = 0;
popt->showassoc = 0;
popt->check = 'u'; /* unset */
popt->nocompress = 0;
popt->blocksize = 1024;
popt->fmode = popt->dmode = ISOFS_INVALID_MODE;
popt->uid_set = 0;
popt->gid_set = 0;
popt->gid = GLOBAL_ROOT_GID;
popt->uid = GLOBAL_ROOT_UID;
popt->iocharset = NULL;
popt->utf8 = 0;
popt->overriderockperm = 0;
popt->session=-1;
popt->sbsector=-1;
if (!options)
return 1;
while ((p = strsep(&options, ",")) != NULL) {
int token;
substring_t args[MAX_OPT_ARGS];
unsigned n;
if (!*p)
continue;
token = match_token(p, tokens, args);
switch (token) {
case Opt_norock:
popt->rock = 0;
break;
case Opt_nojoliet:
popt->joliet = 0;
break;
case Opt_hide:
popt->hide = 1;
break;
case Opt_unhide:
case Opt_showassoc:
popt->showassoc = 1;
break;
case Opt_cruft:
popt->cruft = 1;
break;
case Opt_utf8:
popt->utf8 = 1;
break;
#ifdef CONFIG_JOLIET
case Opt_iocharset:
popt->iocharset = match_strdup(&args[0]);
break;
#endif
case Opt_map_a:
popt->map = 'a';
break;
case Opt_map_o:
popt->map = 'o';
break;
case Opt_map_n:
popt->map = 'n';
break;
case Opt_session:
if (match_int(&args[0], &option))
return 0;
n = option;
if (n > 99)
return 0;
popt->session = n + 1;
break;
case Opt_sb:
if (match_int(&args[0], &option))
return 0;
popt->sbsector = option;
break;
case Opt_check_r:
popt->check = 'r';
break;
case Opt_check_s:
popt->check = 's';
break;
case Opt_ignore:
break;
case Opt_uid:
if (match_int(&args[0], &option))
return 0;
popt->uid = make_kuid(current_user_ns(), option);
if (!uid_valid(popt->uid))
return 0;
popt->uid_set = 1;
break;
case Opt_gid:
if (match_int(&args[0], &option))
return 0;
popt->gid = make_kgid(current_user_ns(), option);
if (!gid_valid(popt->gid))
return 0;
popt->gid_set = 1;
break;
case Opt_mode:
if (match_int(&args[0], &option))
return 0;
popt->fmode = option;
break;
case Opt_dmode:
if (match_int(&args[0], &option))
return 0;
popt->dmode = option;
break;
case Opt_overriderockperm:
popt->overriderockperm = 1;
break;
case Opt_block:
if (match_int(&args[0], &option))
return 0;
n = option;
if (n != 512 && n != 1024 && n != 2048)
return 0;
popt->blocksize = n;
break;
case Opt_nocompress:
popt->nocompress = 1;
break;
default:
return 0;
}
}
return 1;
}
/*
* look if the driver can tell the multi session redirection value
*
* don't change this if you don't know what you do, please!
* Multisession is legal only with XA disks.
* A non-XA disk with more than one volume descriptor may do it right, but
* usually is written in a nowhere standardized "multi-partition" manner.
* Multisession uses absolute addressing (solely the first frame of the whole
* track is #0), multi-partition uses relative addressing (each first frame of
* each track is #0), and a track is not a session.
*
* A broken CDwriter software or drive firmware does not set new standards,
* at least not if conflicting with the existing ones.
*
* emoenke@gwdg.de
*/
#define WE_OBEY_THE_WRITTEN_STANDARDS 1
static unsigned int isofs_get_last_session(struct super_block *sb, s32 session)
{
struct cdrom_multisession ms_info;
unsigned int vol_desc_start;
struct block_device *bdev = sb->s_bdev;
int i;
vol_desc_start=0;
ms_info.addr_format=CDROM_LBA;
if(session >= 0 && session <= 99) {
struct cdrom_tocentry Te;
Te.cdte_track=session;
Te.cdte_format=CDROM_LBA;
i = ioctl_by_bdev(bdev, CDROMREADTOCENTRY, (unsigned long) &Te);
if (!i) {
printk(KERN_DEBUG "ISOFS: Session %d start %d type %d\n",
session, Te.cdte_addr.lba,
Te.cdte_ctrl&CDROM_DATA_TRACK);
if ((Te.cdte_ctrl&CDROM_DATA_TRACK) == 4)
return Te.cdte_addr.lba;
}
printk(KERN_ERR "ISOFS: Invalid session number or type of track\n");
}
i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long) &ms_info);
if (session > 0)
printk(KERN_ERR "ISOFS: Invalid session number\n");
#if 0
printk(KERN_DEBUG "isofs.inode: CDROMMULTISESSION: rc=%d\n",i);
if (i==0) {
printk(KERN_DEBUG "isofs.inode: XA disk: %s\n",ms_info.xa_flag?"yes":"no");
printk(KERN_DEBUG "isofs.inode: vol_desc_start = %d\n", ms_info.addr.lba);
}
#endif
if (i==0)
#if WE_OBEY_THE_WRITTEN_STANDARDS
if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
#endif
vol_desc_start=ms_info.addr.lba;
return vol_desc_start;
}
/*
* Check if root directory is empty (has less than 3 files).
*
* Used to detect broken CDs where ISO root directory is empty but Joliet root
* directory is OK. If such CD has Rock Ridge extensions, they will be disabled
* (and Joliet used instead) or else no files would be visible.
*/
static bool rootdir_empty(struct super_block *sb, unsigned long block)
{
int offset = 0, files = 0, de_len;
struct iso_directory_record *de;
struct buffer_head *bh;
bh = sb_bread(sb, block);
if (!bh)
return true;
while (files < 3) {
de = (struct iso_directory_record *) (bh->b_data + offset);
de_len = *(unsigned char *) de;
if (de_len == 0)
break;
files++;
offset += de_len;
}
brelse(bh);
return files < 3;
}
/*
* Initialize the superblock and read the root inode.
*
* Note: a check_disk_change() has been done immediately prior
* to this call, so we don't need to check again.
*/
static int isofs_fill_super(struct super_block *s, void *data, int silent)
{
struct buffer_head *bh = NULL, *pri_bh = NULL;
struct hs_primary_descriptor *h_pri = NULL;
struct iso_primary_descriptor *pri = NULL;
struct iso_supplementary_descriptor *sec = NULL;
struct iso_directory_record *rootp;
struct inode *inode;
struct iso9660_options opt;
struct isofs_sb_info *sbi;
unsigned long first_data_zone;
int joliet_level = 0;
int iso_blknum, block;
int orig_zonesize;
int table, error = -EINVAL;
unsigned int vol_desc_start;
save_mount_options(s, data);
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
s->s_fs_info = sbi;
if (!parse_options((char *)data, &opt))
goto out_freesbi;
/*
* First of all, get the hardware blocksize for this device.
* If we don't know what it is, or the hardware blocksize is
* larger than the blocksize the user specified, then use
* that value.
*/
/*
* What if bugger tells us to go beyond page size?
*/
opt.blocksize = sb_min_blocksize(s, opt.blocksize);
sbi->s_high_sierra = 0; /* default is iso9660 */
vol_desc_start = (opt.sbsector != -1) ?
opt.sbsector : isofs_get_last_session(s,opt.session);
for (iso_blknum = vol_desc_start+16;
iso_blknum < vol_desc_start+100; iso_blknum++) {
struct hs_volume_descriptor *hdp;
struct iso_volume_descriptor *vdp;
block = iso_blknum << (ISOFS_BLOCK_BITS - s->s_blocksize_bits);
if (!(bh = sb_bread(s, block)))
goto out_no_read;
vdp = (struct iso_volume_descriptor *)bh->b_data;
hdp = (struct hs_volume_descriptor *)bh->b_data;
/*
* Due to the overlapping physical location of the descriptors,
* ISO CDs can match hdp->id==HS_STANDARD_ID as well. To ensure
* proper identification in this case, we first check for ISO.
*/
if (strncmp (vdp->id, ISO_STANDARD_ID, sizeof vdp->id) == 0) {
if (isonum_711(vdp->type) == ISO_VD_END)
break;
if (isonum_711(vdp->type) == ISO_VD_PRIMARY) {
if (pri == NULL) {
pri = (struct iso_primary_descriptor *)vdp;
/* Save the buffer in case we need it ... */
pri_bh = bh;
bh = NULL;
}
}
#ifdef CONFIG_JOLIET
else if (isonum_711(vdp->type) == ISO_VD_SUPPLEMENTARY) {
sec = (struct iso_supplementary_descriptor *)vdp;
if (sec->escape[0] == 0x25 && sec->escape[1] == 0x2f) {
if (opt.joliet) {
if (sec->escape[2] == 0x40)
joliet_level = 1;
else if (sec->escape[2] == 0x43)
joliet_level = 2;
else if (sec->escape[2] == 0x45)
joliet_level = 3;
printk(KERN_DEBUG "ISO 9660 Extensions: "
"Microsoft Joliet Level %d\n",
joliet_level);
}
goto root_found;
} else {
/* Unknown supplementary volume descriptor */
sec = NULL;
}
}
#endif
} else {
if (strncmp (hdp->id, HS_STANDARD_ID, sizeof hdp->id) == 0) {
if (isonum_711(hdp->type) != ISO_VD_PRIMARY)
goto out_freebh;
sbi->s_high_sierra = 1;
opt.rock = 0;
h_pri = (struct hs_primary_descriptor *)vdp;
goto root_found;
}
}
/* Just skip any volume descriptors we don't recognize */
brelse(bh);
bh = NULL;
}
/*
* If we fall through, either no volume descriptor was found,
* or else we passed a primary descriptor looking for others.
*/
if (!pri)
goto out_unknown_format;
brelse(bh);
bh = pri_bh;
pri_bh = NULL;
root_found:
if (joliet_level && (pri == NULL || !opt.rock)) {
/* This is the case of Joliet with the norock mount flag.
* A disc with both Joliet and Rock Ridge is handled later
*/
pri = (struct iso_primary_descriptor *) sec;
}
if(sbi->s_high_sierra){
rootp = (struct iso_directory_record *) h_pri->root_directory_record;
sbi->s_nzones = isonum_733(h_pri->volume_space_size);
sbi->s_log_zone_size = isonum_723(h_pri->logical_block_size);
sbi->s_max_size = isonum_733(h_pri->volume_space_size);
} else {
if (!pri)
goto out_freebh;
rootp = (struct iso_directory_record *) pri->root_directory_record;
sbi->s_nzones = isonum_733(pri->volume_space_size);
sbi->s_log_zone_size = isonum_723(pri->logical_block_size);
sbi->s_max_size = isonum_733(pri->volume_space_size);
}
sbi->s_ninodes = 0; /* No way to figure this out easily */
orig_zonesize = sbi->s_log_zone_size;
/*
* If the zone size is smaller than the hardware sector size,
* this is a fatal error. This would occur if the disc drive
* had sectors that were 2048 bytes, but the filesystem had
* blocks that were 512 bytes (which should only very rarely
* happen.)
*/
if (orig_zonesize < opt.blocksize)
goto out_bad_size;
/* RDE: convert log zone size to bit shift */
switch (sbi->s_log_zone_size) {
case 512: sbi->s_log_zone_size = 9; break;
case 1024: sbi->s_log_zone_size = 10; break;
case 2048: sbi->s_log_zone_size = 11; break;
default:
goto out_bad_zone_size;
}
s->s_magic = ISOFS_SUPER_MAGIC;
/*
* With multi-extent files, file size is only limited by the maximum
* size of a file system, which is 8 TB.
*/
s->s_maxbytes = 0x80000000000LL;
/*
* The CDROM is read-only, has no nodes (devices) on it, and since
* all of the files appear to be owned by root, we really do not want
* to allow suid. (suid or devices will not show up unless we have
* Rock Ridge extensions)
*/
s->s_flags |= MS_RDONLY /* | MS_NODEV | MS_NOSUID */;
/* Set this for reference. Its not currently used except on write
which we don't have .. */
first_data_zone = isonum_733(rootp->extent) +
isonum_711(rootp->ext_attr_length);
sbi->s_firstdatazone = first_data_zone;
#ifndef BEQUIET
printk(KERN_DEBUG "ISOFS: Max size:%ld Log zone size:%ld\n",
sbi->s_max_size, 1UL << sbi->s_log_zone_size);
printk(KERN_DEBUG "ISOFS: First datazone:%ld\n", sbi->s_firstdatazone);
if(sbi->s_high_sierra)
printk(KERN_DEBUG "ISOFS: Disc in High Sierra format.\n");
#endif
/*
* If the Joliet level is set, we _may_ decide to use the
* secondary descriptor, but can't be sure until after we
* read the root inode. But before reading the root inode
* we may need to change the device blocksize, and would
* rather release the old buffer first. So, we cache the
* first_data_zone value from the secondary descriptor.
*/
if (joliet_level) {
pri = (struct iso_primary_descriptor *) sec;
rootp = (struct iso_directory_record *)
pri->root_directory_record;
first_data_zone = isonum_733(rootp->extent) +
isonum_711(rootp->ext_attr_length);
}
/*
* We're all done using the volume descriptor, and may need
* to change the device blocksize, so release the buffer now.
*/
brelse(pri_bh);
brelse(bh);
/*
* Force the blocksize to 512 for 512 byte sectors. The file
* read primitives really get it wrong in a bad way if we don't
* do this.
*
* Note - we should never be setting the blocksize to something
* less than the hardware sector size for the device. If we
* do, we would end up having to read larger buffers and split
* out portions to satisfy requests.
*
* Note2- the idea here is that we want to deal with the optimal
* zonesize in the filesystem. If we have it set to something less,
* then we have horrible problems with trying to piece together
* bits of adjacent blocks in order to properly read directory
* entries. By forcing the blocksize in this way, we ensure
* that we will never be required to do this.
*/
sb_set_blocksize(s, orig_zonesize);
sbi->s_nls_iocharset = NULL;
#ifdef CONFIG_JOLIET
if (joliet_level && opt.utf8 == 0) {
char *p = opt.iocharset ? opt.iocharset : CONFIG_NLS_DEFAULT;
sbi->s_nls_iocharset = load_nls(p);
if (! sbi->s_nls_iocharset) {
/* Fail only if explicit charset specified */
if (opt.iocharset)
goto out_freesbi;
sbi->s_nls_iocharset = load_nls_default();
}
}
#endif
s->s_op = &isofs_sops;
s->s_export_op = &isofs_export_ops;
sbi->s_mapping = opt.map;
sbi->s_rock = (opt.rock ? 2 : 0);
sbi->s_rock_offset = -1; /* initial offset, will guess until SP is found*/
sbi->s_cruft = opt.cruft;
sbi->s_hide = opt.hide;
sbi->s_showassoc = opt.showassoc;
sbi->s_uid = opt.uid;
sbi->s_gid = opt.gid;
sbi->s_uid_set = opt.uid_set;
sbi->s_gid_set = opt.gid_set;
sbi->s_utf8 = opt.utf8;
sbi->s_nocompress = opt.nocompress;
sbi->s_overriderockperm = opt.overriderockperm;
/*
* It would be incredibly stupid to allow people to mark every file
* on the disk as suid, so we merely allow them to set the default
* permissions.
*/
if (opt.fmode != ISOFS_INVALID_MODE)
sbi->s_fmode = opt.fmode & 0777;
else
sbi->s_fmode = ISOFS_INVALID_MODE;
if (opt.dmode != ISOFS_INVALID_MODE)
sbi->s_dmode = opt.dmode & 0777;
else
sbi->s_dmode = ISOFS_INVALID_MODE;
/*
* Read the root inode, which _may_ result in changing
* the s_rock flag. Once we have the final s_rock value,
* we then decide whether to use the Joliet descriptor.
*/
inode = isofs_iget(s, sbi->s_firstdatazone, 0);
if (IS_ERR(inode))
goto out_no_root;
/*
* Fix for broken CDs with Rock Ridge and empty ISO root directory but
* correct Joliet root directory.
*/
if (sbi->s_rock == 1 && joliet_level &&
rootdir_empty(s, sbi->s_firstdatazone)) {
printk(KERN_NOTICE
"ISOFS: primary root directory is empty. "
"Disabling Rock Ridge and switching to Joliet.");
sbi->s_rock = 0;
}
/*
* If this disk has both Rock Ridge and Joliet on it, then we
* want to use Rock Ridge by default. This can be overridden
* by using the norock mount option. There is still one other
* possibility that is not taken into account: a Rock Ridge
* CD with Unicode names. Until someone sees such a beast, it
* will not be supported.
*/
if (sbi->s_rock == 1) {
joliet_level = 0;
} else if (joliet_level) {
sbi->s_rock = 0;
if (sbi->s_firstdatazone != first_data_zone) {
sbi->s_firstdatazone = first_data_zone;
printk(KERN_DEBUG
"ISOFS: changing to secondary root\n");
iput(inode);
inode = isofs_iget(s, sbi->s_firstdatazone, 0);
if (IS_ERR(inode))
goto out_no_root;
}
}
if (opt.check == 'u') {
/* Only Joliet is case insensitive by default */
if (joliet_level)
opt.check = 'r';
else
opt.check = 's';
}
sbi->s_joliet_level = joliet_level;
/* Make sure the root inode is a directory */
if (!S_ISDIR(inode->i_mode)) {
printk(KERN_WARNING
"isofs_fill_super: root inode is not a directory. "
"Corrupted media?\n");
goto out_iput;
}
table = 0;
if (joliet_level)
table += 2;
if (opt.check == 'r')
table++;
s->s_d_op = &isofs_dentry_ops[table];
/* get the root dentry */
s->s_root = d_make_root(inode);
if (!(s->s_root)) {
error = -ENOMEM;
goto out_no_inode;
}
kfree(opt.iocharset);
return 0;
/*
* Display error messages and free resources.
*/
out_iput:
iput(inode);
goto out_no_inode;
out_no_root:
error = PTR_ERR(inode);
if (error != -ENOMEM)
printk(KERN_WARNING "%s: get root inode failed\n", __func__);
out_no_inode:
#ifdef CONFIG_JOLIET
unload_nls(sbi->s_nls_iocharset);
#endif
goto out_freesbi;
out_no_read:
printk(KERN_WARNING "%s: bread failed, dev=%s, iso_blknum=%d, block=%d\n",
__func__, s->s_id, iso_blknum, block);
goto out_freebh;
out_bad_zone_size:
printk(KERN_WARNING "ISOFS: Bad logical zone size %ld\n",
sbi->s_log_zone_size);
goto out_freebh;
out_bad_size:
printk(KERN_WARNING "ISOFS: Logical zone size(%d) < hardware blocksize(%u)\n",
orig_zonesize, opt.blocksize);
goto out_freebh;
out_unknown_format:
if (!silent)
printk(KERN_WARNING "ISOFS: Unable to identify CD-ROM format.\n");
out_freebh:
brelse(bh);
brelse(pri_bh);
out_freesbi:
kfree(opt.iocharset);
kfree(sbi);
s->s_fs_info = NULL;
return error;
}
static int isofs_statfs (struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = dentry->d_sb;
u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
buf->f_type = ISOFS_SUPER_MAGIC;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = (ISOFS_SB(sb)->s_nzones
<< (ISOFS_SB(sb)->s_log_zone_size - sb->s_blocksize_bits));
buf->f_bfree = 0;
buf->f_bavail = 0;
buf->f_files = ISOFS_SB(sb)->s_ninodes;
buf->f_ffree = 0;
buf->f_fsid.val[0] = (u32)id;
buf->f_fsid.val[1] = (u32)(id >> 32);
buf->f_namelen = NAME_MAX;
return 0;
}
/*
* Get a set of blocks; filling in buffer_heads if already allocated
* or getblk() if they are not. Returns the number of blocks inserted
* (-ve == error.)
*/
int isofs_get_blocks(struct inode *inode, sector_t iblock,
struct buffer_head **bh, unsigned long nblocks)
{
unsigned long b_off = iblock;
unsigned offset, sect_size;
unsigned int firstext;
unsigned long nextblk, nextoff;
int section, rv, error;
struct iso_inode_info *ei = ISOFS_I(inode);
error = -EIO;
rv = 0;
if (iblock != b_off) {
printk(KERN_DEBUG "%s: block number too large\n", __func__);
goto abort;
}
offset = 0;
firstext = ei->i_first_extent;
sect_size = ei->i_section_size >> ISOFS_BUFFER_BITS(inode);
nextblk = ei->i_next_section_block;
nextoff = ei->i_next_section_offset;
section = 0;
while (nblocks) {
/* If we are *way* beyond the end of the file, print a message.
* Access beyond the end of the file up to the next page boundary
* is normal, however because of the way the page cache works.
* In this case, we just return 0 so that we can properly fill
* the page with useless information without generating any
* I/O errors.
*/
if (b_off > ((inode->i_size + PAGE_CACHE_SIZE - 1) >> ISOFS_BUFFER_BITS(inode))) {
printk(KERN_DEBUG "%s: block >= EOF (%lu, %llu)\n",
__func__, b_off,
(unsigned long long)inode->i_size);
goto abort;
}
/* On the last section, nextblk == 0, section size is likely to
* exceed sect_size by a partial block, and access beyond the
* end of the file will reach beyond the section size, too.
*/
while (nextblk && (b_off >= (offset + sect_size))) {
struct inode *ninode;
offset += sect_size;
ninode = isofs_iget(inode->i_sb, nextblk, nextoff);
if (IS_ERR(ninode)) {
error = PTR_ERR(ninode);
goto abort;
}
firstext = ISOFS_I(ninode)->i_first_extent;
sect_size = ISOFS_I(ninode)->i_section_size >> ISOFS_BUFFER_BITS(ninode);
nextblk = ISOFS_I(ninode)->i_next_section_block;
nextoff = ISOFS_I(ninode)->i_next_section_offset;
iput(ninode);
if (++section > 100) {
printk(KERN_DEBUG "%s: More than 100 file sections ?!?"
" aborting...\n", __func__);
printk(KERN_DEBUG "%s: block=%lu firstext=%u sect_size=%u "
"nextblk=%lu nextoff=%lu\n", __func__,
b_off, firstext, (unsigned) sect_size,
nextblk, nextoff);
goto abort;
}
}
if (*bh) {
map_bh(*bh, inode->i_sb, firstext + b_off - offset);
} else {
*bh = sb_getblk(inode->i_sb, firstext+b_off-offset);
if (!*bh)
goto abort;
}
bh++; /* Next buffer head */
b_off++; /* Next buffer offset */
nblocks--;
rv++;
}
error = 0;
abort:
return rv != 0 ? rv : error;
}
/*
* Used by the standard interfaces.
*/
static int isofs_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create)
{
int ret;
if (create) {
printk(KERN_DEBUG "%s: Kernel tries to allocate a block\n", __func__);
return -EROFS;
}
ret = isofs_get_blocks(inode, iblock, &bh_result, 1);
return ret < 0 ? ret : 0;
}
static int isofs_bmap(struct inode *inode, sector_t block)
{
struct buffer_head dummy;
int error;
dummy.b_state = 0;
dummy.b_blocknr = -1000;
error = isofs_get_block(inode, block, &dummy, 0);
if (!error)
return dummy.b_blocknr;
return 0;
}
struct buffer_head *isofs_bread(struct inode *inode, sector_t block)
{
sector_t blknr = isofs_bmap(inode, block);
if (!blknr)
return NULL;
return sb_bread(inode->i_sb, blknr);
}
static int isofs_readpage(struct file *file, struct page *page)
{
return mpage_readpage(page, isofs_get_block);
}
static int isofs_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
return mpage_readpages(mapping, pages, nr_pages, isofs_get_block);
}
static sector_t _isofs_bmap(struct address_space *mapping, sector_t block)
{
return generic_block_bmap(mapping,block,isofs_get_block);
}
static const struct address_space_operations isofs_aops = {
.readpage = isofs_readpage,
.readpages = isofs_readpages,
.bmap = _isofs_bmap
};
static int isofs_read_level3_size(struct inode *inode)
{
unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
int high_sierra = ISOFS_SB(inode->i_sb)->s_high_sierra;
struct buffer_head *bh = NULL;
unsigned long block, offset, block_saved, offset_saved;
int i = 0;
int more_entries = 0;
struct iso_directory_record *tmpde = NULL;
struct iso_inode_info *ei = ISOFS_I(inode);
inode->i_size = 0;
/* The first 16 blocks are reserved as the System Area. Thus,
* no inodes can appear in block 0. We use this to flag that
* this is the last section. */
ei->i_next_section_block = 0;
ei->i_next_section_offset = 0;
block = ei->i_iget5_block;
offset = ei->i_iget5_offset;
do {
struct iso_directory_record *de;
unsigned int de_len;
if (!bh) {
bh = sb_bread(inode->i_sb, block);
if (!bh)
goto out_noread;
}
de = (struct iso_directory_record *) (bh->b_data + offset);
de_len = *(unsigned char *) de;
if (de_len == 0) {
brelse(bh);
bh = NULL;
++block;
offset = 0;
continue;
}
block_saved = block;
offset_saved = offset;
offset += de_len;
/* Make sure we have a full directory entry */
if (offset >= bufsize) {
int slop = bufsize - offset + de_len;
if (!tmpde) {
tmpde = kmalloc(256, GFP_KERNEL);
if (!tmpde)
goto out_nomem;
}
memcpy(tmpde, de, slop);
offset &= bufsize - 1;
block++;
brelse(bh);
bh = NULL;
if (offset) {
bh = sb_bread(inode->i_sb, block);
if (!bh)
goto out_noread;
memcpy((void *)tmpde+slop, bh->b_data, offset);
}
de = tmpde;
}
inode->i_size += isonum_733(de->size);
if (i == 1) {
ei->i_next_section_block = block_saved;
ei->i_next_section_offset = offset_saved;
}
more_entries = de->flags[-high_sierra] & 0x80;
i++;
if (i > 100)
goto out_toomany;
} while (more_entries);
out:
kfree(tmpde);
if (bh)
brelse(bh);
return 0;
out_nomem:
if (bh)
brelse(bh);
return -ENOMEM;
out_noread:
printk(KERN_INFO "ISOFS: unable to read i-node block %lu\n", block);
kfree(tmpde);
return -EIO;
out_toomany:
printk(KERN_INFO "%s: More than 100 file sections ?!?, aborting...\n"
"isofs_read_level3_size: inode=%lu\n",
__func__, inode->i_ino);
goto out;
}
static int isofs_read_inode(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
struct isofs_sb_info *sbi = ISOFS_SB(sb);
unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
unsigned long block;
int high_sierra = sbi->s_high_sierra;
struct buffer_head *bh = NULL;
struct iso_directory_record *de;
struct iso_directory_record *tmpde = NULL;
unsigned int de_len;
unsigned long offset;
struct iso_inode_info *ei = ISOFS_I(inode);
int ret = -EIO;
block = ei->i_iget5_block;
bh = sb_bread(inode->i_sb, block);
if (!bh)
goto out_badread;
offset = ei->i_iget5_offset;
de = (struct iso_directory_record *) (bh->b_data + offset);
de_len = *(unsigned char *) de;
if (offset + de_len > bufsize) {
int frag1 = bufsize - offset;
tmpde = kmalloc(de_len, GFP_KERNEL);
if (tmpde == NULL) {
printk(KERN_INFO "%s: out of memory\n", __func__);
ret = -ENOMEM;
goto fail;
}
memcpy(tmpde, bh->b_data + offset, frag1);
brelse(bh);
bh = sb_bread(inode->i_sb, ++block);
if (!bh)
goto out_badread;
memcpy((char *)tmpde+frag1, bh->b_data, de_len - frag1);
de = tmpde;
}
inode->i_ino = isofs_get_ino(ei->i_iget5_block,
ei->i_iget5_offset,
ISOFS_BUFFER_BITS(inode));
/* Assume it is a normal-format file unless told otherwise */
ei->i_file_format = isofs_file_normal;
if (de->flags[-high_sierra] & 2) {
if (sbi->s_dmode != ISOFS_INVALID_MODE)
inode->i_mode = S_IFDIR | sbi->s_dmode;
else
inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
set_nlink(inode, 1); /*
* Set to 1. We know there are 2, but
* the find utility tries to optimize
* if it is 2, and it screws up. It is
* easier to give 1 which tells find to
* do it the hard way.
*/
} else {
if (sbi->s_fmode != ISOFS_INVALID_MODE) {
inode->i_mode = S_IFREG | sbi->s_fmode;
} else {
/*
* Set default permissions: r-x for all. The disc
* could be shared with DOS machines so virtually
* anything could be a valid executable.
*/
inode->i_mode = S_IFREG | S_IRUGO | S_IXUGO;
}
set_nlink(inode, 1);
}
inode->i_uid = sbi->s_uid;
inode->i_gid = sbi->s_gid;
inode->i_blocks = 0;
ei->i_format_parm[0] = 0;
ei->i_format_parm[1] = 0;
ei->i_format_parm[2] = 0;
ei->i_section_size = isonum_733(de->size);
if (de->flags[-high_sierra] & 0x80) {
ret = isofs_read_level3_size(inode);
if (ret < 0)
goto fail;
ret = -EIO;
} else {
ei->i_next_section_block = 0;
ei->i_next_section_offset = 0;
inode->i_size = isonum_733(de->size);
}
/*
* Some dipshit decided to store some other bit of information
* in the high byte of the file length. Truncate size in case
* this CDROM was mounted with the cruft option.
*/
if (sbi->s_cruft)
inode->i_size &= 0x00ffffff;
if (de->interleave[0]) {
printk(KERN_DEBUG "ISOFS: Interleaved files not (yet) supported.\n");
inode->i_size = 0;
}
/* I have no idea what file_unit_size is used for, so
we will flag it for now */
if (de->file_unit_size[0] != 0) {
printk(KERN_DEBUG "ISOFS: File unit size != 0 for ISO file (%ld).\n",
inode->i_ino);
}
/* I have no idea what other flag bits are used for, so
we will flag it for now */
#ifdef DEBUG
if((de->flags[-high_sierra] & ~2)!= 0){
printk(KERN_DEBUG "ISOFS: Unusual flag settings for ISO file "
"(%ld %x).\n",
inode->i_ino, de->flags[-high_sierra]);
}
#endif
inode->i_mtime.tv_sec =
inode->i_atime.tv_sec =
inode->i_ctime.tv_sec = iso_date(de->date, high_sierra);
inode->i_mtime.tv_nsec =
inode->i_atime.tv_nsec =
inode->i_ctime.tv_nsec = 0;
ei->i_first_extent = (isonum_733(de->extent) +
isonum_711(de->ext_attr_length));
/* Set the number of blocks for stat() - should be done before RR */
inode->i_blocks = (inode->i_size + 511) >> 9;
/*
* Now test for possible Rock Ridge extensions which will override
* some of these numbers in the inode structure.
*/
if (!high_sierra) {
parse_rock_ridge_inode(de, inode);
/* if we want uid/gid set, override the rock ridge setting */
if (sbi->s_uid_set)
inode->i_uid = sbi->s_uid;
if (sbi->s_gid_set)
inode->i_gid = sbi->s_gid;
}
/* Now set final access rights if overriding rock ridge setting */
if (S_ISDIR(inode->i_mode) && sbi->s_overriderockperm &&
sbi->s_dmode != ISOFS_INVALID_MODE)
inode->i_mode = S_IFDIR | sbi->s_dmode;
if (S_ISREG(inode->i_mode) && sbi->s_overriderockperm &&
sbi->s_fmode != ISOFS_INVALID_MODE)
inode->i_mode = S_IFREG | sbi->s_fmode;
/* Install the inode operations vector */
if (S_ISREG(inode->i_mode)) {
inode->i_fop = &generic_ro_fops;
switch (ei->i_file_format) {
#ifdef CONFIG_ZISOFS
case isofs_file_compressed:
inode->i_data.a_ops = &zisofs_aops;
break;
#endif
default:
inode->i_data.a_ops = &isofs_aops;
break;
}
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = &isofs_dir_inode_operations;
inode->i_fop = &isofs_dir_operations;
} else if (S_ISLNK(inode->i_mode)) {
inode->i_op = &page_symlink_inode_operations;
inode->i_data.a_ops = &isofs_symlink_aops;
} else
/* XXX - parse_rock_ridge_inode() had already set i_rdev. */
init_special_inode(inode, inode->i_mode, inode->i_rdev);
ret = 0;
out:
kfree(tmpde);
if (bh)
brelse(bh);
return ret;
out_badread:
printk(KERN_WARNING "ISOFS: unable to read i-node block\n");
fail:
goto out;
}
struct isofs_iget5_callback_data {
unsigned long block;
unsigned long offset;
};
static int isofs_iget5_test(struct inode *ino, void *data)
{
struct iso_inode_info *i = ISOFS_I(ino);
struct isofs_iget5_callback_data *d =
(struct isofs_iget5_callback_data*)data;
return (i->i_iget5_block == d->block)
&& (i->i_iget5_offset == d->offset);
}
static int isofs_iget5_set(struct inode *ino, void *data)
{
struct iso_inode_info *i = ISOFS_I(ino);
struct isofs_iget5_callback_data *d =
(struct isofs_iget5_callback_data*)data;
i->i_iget5_block = d->block;
i->i_iget5_offset = d->offset;
return 0;
}
/* Store, in the inode's containing structure, the block and block
* offset that point to the underlying meta-data for the inode. The
* code below is otherwise similar to the iget() code in
* include/linux/fs.h */
struct inode *isofs_iget(struct super_block *sb,
unsigned long block,
unsigned long offset)
{
unsigned long hashval;
struct inode *inode;
struct isofs_iget5_callback_data data;
long ret;
if (offset >= 1ul << sb->s_blocksize_bits)
return ERR_PTR(-EINVAL);
data.block = block;
data.offset = offset;
hashval = (block << sb->s_blocksize_bits) | offset;
inode = iget5_locked(sb, hashval, &isofs_iget5_test,
&isofs_iget5_set, &data);
if (!inode)
return ERR_PTR(-ENOMEM);
if (inode->i_state & I_NEW) {
ret = isofs_read_inode(inode);
if (ret < 0) {
iget_failed(inode);
inode = ERR_PTR(ret);
} else {
unlock_new_inode(inode);
}
}
return inode;
}
static struct dentry *isofs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
}
static struct file_system_type iso9660_fs_type = {
.owner = THIS_MODULE,
.name = "iso9660",
.mount = isofs_mount,
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
MODULE_ALIAS_FS("iso9660");
MODULE_ALIAS("iso9660");
static int __init init_iso9660_fs(void)
{
int err = init_inodecache();
if (err)
goto out;
#ifdef CONFIG_ZISOFS
err = zisofs_init();
if (err)
goto out1;
#endif
err = register_filesystem(&iso9660_fs_type);
if (err)
goto out2;
return 0;
out2:
#ifdef CONFIG_ZISOFS
zisofs_cleanup();
out1:
#endif
destroy_inodecache();
out:
return err;
}
static void __exit exit_iso9660_fs(void)
{
unregister_filesystem(&iso9660_fs_type);
#ifdef CONFIG_ZISOFS
zisofs_cleanup();
#endif
destroy_inodecache();
}
module_init(init_iso9660_fs)
module_exit(exit_iso9660_fs)
MODULE_LICENSE("GPL");
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