diff options
Diffstat (limited to 'fs/hpfs/super.c')
-rw-r--r-- | fs/hpfs/super.c | 712 |
1 files changed, 712 insertions, 0 deletions
diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c new file mode 100644 index 00000000..98580a3b --- /dev/null +++ b/fs/hpfs/super.c @@ -0,0 +1,712 @@ +/* + * linux/fs/hpfs/super.c + * + * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 + * + * mounting, unmounting, error handling + */ + +#include "hpfs_fn.h" +#include <linux/module.h> +#include <linux/parser.h> +#include <linux/init.h> +#include <linux/statfs.h> +#include <linux/magic.h> +#include <linux/sched.h> +#include <linux/bitmap.h> +#include <linux/slab.h> + +/* Mark the filesystem dirty, so that chkdsk checks it when os/2 booted */ + +static void mark_dirty(struct super_block *s, int remount) +{ + if (hpfs_sb(s)->sb_chkdsk && (remount || !(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); + sync_dirty_buffer(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; + sync_blockdev(s->s_bdev); + if ((sb = hpfs_map_sector(s, 17, &bh, 0))) { + sb->dirty = hpfs_sb(s)->sb_chkdsk > 1 - hpfs_sb(s)->sb_was_error; + sb->old_wrote = hpfs_sb(s)->sb_chkdsk >= 2 && !hpfs_sb(s)->sb_was_error; + mark_buffer_dirty(bh); + sync_dirty_buffer(bh); + brelse(bh); + } +} + +/* Filesystem error... */ +static char err_buf[1024]; + +void hpfs_error(struct super_block *s, const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + vsnprintf(err_buf, sizeof(err_buf), fmt, args); + va_end(args); + + printk("HPFS: filesystem error: %s", err_buf); + if (!hpfs_sb(s)->sb_was_error) { + if (hpfs_sb(s)->sb_err == 2) { + printk("; crashing the system because you wanted it\n"); + mark_dirty(s, 0); + panic("HPFS panic"); + } else if (hpfs_sb(s)->sb_err == 1) { + if (s->s_flags & MS_RDONLY) printk("; already mounted read-only\n"); + else { + printk("; remounting read-only\n"); + mark_dirty(s, 0); + 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"); + hpfs_sb(s)->sb_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; +} + +static void hpfs_put_super(struct super_block *s) +{ + struct hpfs_sb_info *sbi = hpfs_sb(s); + + hpfs_lock(s); + unmark_dirty(s); + hpfs_unlock(s); + + kfree(sbi->sb_cp_table); + kfree(sbi->sb_bmp_dir); + s->s_fs_info = NULL; + kfree(sbi); +} + +unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno) +{ + struct quad_buffer_head qbh; + unsigned long *bits; + unsigned count; + + bits = hpfs_map_4sectors(s, secno, &qbh, 4); + if (!bits) + return 0; + count = bitmap_weight(bits, 2048 * BITS_PER_BYTE); + hpfs_brelse4(&qbh); + return count; +} + +static unsigned count_bitmaps(struct super_block *s) +{ + unsigned n, count, n_bands; + n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14; + count = 0; + for (n = 0; n < n_bands; n++) + count += hpfs_count_one_bitmap(s, le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[n])); + return count; +} + +static int hpfs_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *s = dentry->d_sb; + struct hpfs_sb_info *sbi = hpfs_sb(s); + u64 id = huge_encode_dev(s->s_bdev->bd_dev); + hpfs_lock(s); + + /*if (sbi->sb_n_free == -1) {*/ + sbi->sb_n_free = count_bitmaps(s); + sbi->sb_n_free_dnodes = hpfs_count_one_bitmap(s, sbi->sb_dmap); + /*}*/ + buf->f_type = s->s_magic; + buf->f_bsize = 512; + buf->f_blocks = sbi->sb_fs_size; + buf->f_bfree = sbi->sb_n_free; + buf->f_bavail = sbi->sb_n_free; + buf->f_files = sbi->sb_dirband_size / 4; + buf->f_ffree = sbi->sb_n_free_dnodes; + buf->f_fsid.val[0] = (u32)id; + buf->f_fsid.val[1] = (u32)(id >> 32); + buf->f_namelen = 254; + + hpfs_unlock(s); + + return 0; +} + +static struct kmem_cache * hpfs_inode_cachep; + +static struct inode *hpfs_alloc_inode(struct super_block *sb) +{ + struct hpfs_inode_info *ei; + ei = (struct hpfs_inode_info *)kmem_cache_alloc(hpfs_inode_cachep, GFP_NOFS); + if (!ei) + return NULL; + ei->vfs_inode.i_version = 1; + return &ei->vfs_inode; +} + +static void hpfs_i_callback(struct rcu_head *head) +{ + struct inode *inode = container_of(head, struct inode, i_rcu); + INIT_LIST_HEAD(&inode->i_dentry); + kmem_cache_free(hpfs_inode_cachep, hpfs_i(inode)); +} + +static void hpfs_destroy_inode(struct inode *inode) +{ + call_rcu(&inode->i_rcu, hpfs_i_callback); +} + +static void init_once(void *foo) +{ + struct hpfs_inode_info *ei = (struct hpfs_inode_info *) foo; + + inode_init_once(&ei->vfs_inode); +} + +static int init_inodecache(void) +{ + hpfs_inode_cachep = kmem_cache_create("hpfs_inode_cache", + sizeof(struct hpfs_inode_info), + 0, (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD), + init_once); + if (hpfs_inode_cachep == NULL) + return -ENOMEM; + return 0; +} + +static void destroy_inodecache(void) +{ + kmem_cache_destroy(hpfs_inode_cachep); +} + +/* + * A tiny parser for option strings, stolen from dosfs. + * Stolen again from read-only hpfs. + * And updated for table-driven option parsing. + */ + +enum { + Opt_help, Opt_uid, Opt_gid, Opt_umask, Opt_case_lower, Opt_case_asis, + Opt_check_none, Opt_check_normal, Opt_check_strict, + Opt_err_cont, Opt_err_ro, Opt_err_panic, + Opt_eas_no, Opt_eas_ro, Opt_eas_rw, + Opt_chkdsk_no, Opt_chkdsk_errors, Opt_chkdsk_always, + Opt_timeshift, Opt_err, +}; + +static const match_table_t tokens = { + {Opt_help, "help"}, + {Opt_uid, "uid=%u"}, + {Opt_gid, "gid=%u"}, + {Opt_umask, "umask=%o"}, + {Opt_case_lower, "case=lower"}, + {Opt_case_asis, "case=asis"}, + {Opt_check_none, "check=none"}, + {Opt_check_normal, "check=normal"}, + {Opt_check_strict, "check=strict"}, + {Opt_err_cont, "errors=continue"}, + {Opt_err_ro, "errors=remount-ro"}, + {Opt_err_panic, "errors=panic"}, + {Opt_eas_no, "eas=no"}, + {Opt_eas_ro, "eas=ro"}, + {Opt_eas_rw, "eas=rw"}, + {Opt_chkdsk_no, "chkdsk=no"}, + {Opt_chkdsk_errors, "chkdsk=errors"}, + {Opt_chkdsk_always, "chkdsk=always"}, + {Opt_timeshift, "timeshift=%d"}, + {Opt_err, NULL}, +}; + +static int parse_opts(char *opts, uid_t *uid, gid_t *gid, umode_t *umask, + int *lowercase, int *eas, int *chk, int *errs, + int *chkdsk, int *timeshift) +{ + char *p; + int option; + + if (!opts) + return 1; + + /*printk("Parsing opts: '%s'\n",opts);*/ + + while ((p = strsep(&opts, ",")) != NULL) { + substring_t args[MAX_OPT_ARGS]; + int token; + if (!*p) + continue; + + token = match_token(p, tokens, args); + switch (token) { + case Opt_help: + return 2; + case Opt_uid: + if (match_int(args, &option)) + return 0; + *uid = option; + break; + case Opt_gid: + if (match_int(args, &option)) + return 0; + *gid = option; + break; + case Opt_umask: + if (match_octal(args, &option)) + return 0; + *umask = option; + break; + case Opt_case_lower: + *lowercase = 1; + break; + case Opt_case_asis: + *lowercase = 0; + break; + case Opt_check_none: + *chk = 0; + break; + case Opt_check_normal: + *chk = 1; + break; + case Opt_check_strict: + *chk = 2; + break; + case Opt_err_cont: + *errs = 0; + break; + case Opt_err_ro: + *errs = 1; + break; + case Opt_err_panic: + *errs = 2; + break; + case Opt_eas_no: + *eas = 0; + break; + case Opt_eas_ro: + *eas = 1; + break; + case Opt_eas_rw: + *eas = 2; + break; + case Opt_chkdsk_no: + *chkdsk = 0; + break; + case Opt_chkdsk_errors: + *chkdsk = 1; + break; + case Opt_chkdsk_always: + *chkdsk = 2; + break; + case Opt_timeshift: + { + int m = 1; + char *rhs = args[0].from; + if (!rhs || !*rhs) + return 0; + if (*rhs == '-') m = -1; + if (*rhs == '+' || *rhs == '-') rhs++; + *timeshift = simple_strtoul(rhs, &rhs, 0) * m; + if (*rhs) + return 0; + break; + } + default: + 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\ + 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"); +} + +static int hpfs_remount_fs(struct super_block *s, int *flags, char *data) +{ + uid_t uid; + gid_t gid; + umode_t umask; + int lowercase, eas, chk, errs, chkdsk, timeshift; + int o; + struct hpfs_sb_info *sbi = hpfs_sb(s); + char *new_opts = kstrdup(data, GFP_KERNEL); + + *flags |= MS_NOATIME; + + hpfs_lock(s); + lock_super(s); + uid = sbi->sb_uid; gid = sbi->sb_gid; + umask = 0777 & ~sbi->sb_mode; + lowercase = sbi->sb_lowercase; + eas = sbi->sb_eas; chk = sbi->sb_chk; chkdsk = sbi->sb_chkdsk; + errs = sbi->sb_err; timeshift = sbi->sb_timeshift; + + if (!(o = parse_opts(data, &uid, &gid, &umask, &lowercase, + &eas, &chk, &errs, &chkdsk, ×hift))) { + printk("HPFS: bad mount options.\n"); + goto out_err; + } + if (o == 2) { + hpfs_help(); + goto out_err; + } + if (timeshift != sbi->sb_timeshift) { + printk("HPFS: timeshift can't be changed using remount.\n"); + goto out_err; + } + + unmark_dirty(s); + + sbi->sb_uid = uid; sbi->sb_gid = gid; + sbi->sb_mode = 0777 & ~umask; + sbi->sb_lowercase = lowercase; + sbi->sb_eas = eas; sbi->sb_chk = chk; sbi->sb_chkdsk = chkdsk; + sbi->sb_err = errs; sbi->sb_timeshift = timeshift; + + if (!(*flags & MS_RDONLY)) mark_dirty(s, 1); + + replace_mount_options(s, new_opts); + + unlock_super(s); + hpfs_unlock(s); + return 0; + +out_err: + unlock_super(s); + hpfs_unlock(s); + kfree(new_opts); + return -EINVAL; +} + +/* Super operations */ + +static const struct super_operations hpfs_sops = +{ + .alloc_inode = hpfs_alloc_inode, + .destroy_inode = hpfs_destroy_inode, + .evict_inode = hpfs_evict_inode, + .put_super = hpfs_put_super, + .statfs = hpfs_statfs, + .remount_fs = hpfs_remount_fs, + .show_options = generic_show_options, +}; + +static int hpfs_fill_super(struct super_block *s, void *options, int silent) +{ + struct buffer_head *bh0, *bh1, *bh2; + struct hpfs_boot_block *bootblock; + struct hpfs_super_block *superblock; + struct hpfs_spare_block *spareblock; + struct hpfs_sb_info *sbi; + struct inode *root; + + uid_t uid; + gid_t gid; + umode_t umask; + int lowercase, eas, chk, errs, chkdsk, timeshift; + + dnode_secno root_dno; + struct hpfs_dirent *de = NULL; + struct quad_buffer_head qbh; + + int o; + + save_mount_options(s, options); + + sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); + if (!sbi) { + return -ENOMEM; + } + s->s_fs_info = sbi; + + sbi->sb_bmp_dir = NULL; + sbi->sb_cp_table = NULL; + + mutex_init(&sbi->hpfs_mutex); + hpfs_lock(s); + + uid = current_uid(); + gid = current_gid(); + umask = current_umask(); + lowercase = 0; + eas = 2; + chk = 1; + errs = 1; + chkdsk = 1; + timeshift = 0; + + if (!(o = parse_opts(options, &uid, &gid, &umask, &lowercase, + &eas, &chk, &errs, &chkdsk, ×hift))) { + printk("HPFS: bad mount options.\n"); + goto bail0; + } + if (o==2) { + hpfs_help(); + goto bail0; + } + + /*sbi->sb_mounting = 1;*/ + sb_set_blocksize(s, 512); + sbi->sb_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 (/*le16_to_cpu(bootblock->magic) != BB_MAGIC + ||*/ le32_to_cpu(superblock->magic) != SB_MAGIC + || le32_to_cpu(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_op = &hpfs_sops; + s->s_d_op = &hpfs_dentry_operations; + + sbi->sb_root = le32_to_cpu(superblock->root); + sbi->sb_fs_size = le32_to_cpu(superblock->n_sectors); + sbi->sb_bitmaps = le32_to_cpu(superblock->bitmaps); + sbi->sb_dirband_start = le32_to_cpu(superblock->dir_band_start); + sbi->sb_dirband_size = le32_to_cpu(superblock->n_dir_band); + sbi->sb_dmap = le32_to_cpu(superblock->dir_band_bitmap); + sbi->sb_uid = uid; + sbi->sb_gid = gid; + sbi->sb_mode = 0777 & ~umask; + sbi->sb_n_free = -1; + sbi->sb_n_free_dnodes = -1; + sbi->sb_lowercase = lowercase; + sbi->sb_eas = eas; + sbi->sb_chk = chk; + sbi->sb_chkdsk = chkdsk; + sbi->sb_err = errs; + sbi->sb_timeshift = timeshift; + sbi->sb_was_error = 0; + sbi->sb_cp_table = NULL; + sbi->sb_c_bitmap = -1; + sbi->sb_max_fwd_alloc = 0xffffff; + + /* Load bitmap directory */ + if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, le32_to_cpu(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 (le32_to_cpu(spareblock->hotfixes_used) || le32_to_cpu(spareblock->n_spares_used)) { + if (errs >= 2) { + printk("HPFS: Hotfixes not supported here, try chkdsk\n"); + mark_dirty(s, 0); + 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 (le32_to_cpu(spareblock->n_dnode_spares) != le32_to_cpu(spareblock->n_dnode_spares_free)) { + if (errs >= 2) { + printk("HPFS: Spare dnodes used, try chkdsk\n"); + mark_dirty(s, 0); + 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 (le32_to_cpu(superblock->dir_band_end) - le32_to_cpu(superblock->dir_band_start) + 1 != le32_to_cpu(superblock->n_dir_band) || + le32_to_cpu(superblock->dir_band_end) < le32_to_cpu(superblock->dir_band_start) || le32_to_cpu(superblock->n_dir_band) > 0x4000) { + hpfs_error(s, "dir band size mismatch: dir_band_start==%08x, dir_band_end==%08x, n_dir_band==%08x", + le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->dir_band_end), le32_to_cpu(superblock->n_dir_band)); + goto bail4; + } + a = sbi->sb_dirband_size; + sbi->sb_dirband_size = 0; + if (hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_start), le32_to_cpu(superblock->n_dir_band), "dir_band") || + hpfs_chk_sectors(s, le32_to_cpu(superblock->dir_band_bitmap), 4, "dir_band_bitmap") || + hpfs_chk_sectors(s, le32_to_cpu(superblock->bitmaps), 4, "bitmaps")) { + mark_dirty(s, 0); + goto bail4; + } + sbi->sb_dirband_size = a; + } else printk("HPFS: You really don't want any checks? You are crazy...\n"); + + /* Load code page table */ + if (le32_to_cpu(spareblock->n_code_pages)) + if (!(sbi->sb_cp_table = hpfs_load_code_page(s, le32_to_cpu(spareblock->code_page_dir)))) + printk("HPFS: Warning: code page support is disabled\n"); + + brelse(bh2); + brelse(bh1); + brelse(bh0); + + root = iget_locked(s, sbi->sb_root); + if (!root) + goto bail0; + hpfs_init_inode(root); + hpfs_read_inode(root); + unlock_new_inode(root); + s->s_root = d_alloc_root(root); + if (!s->s_root) { + iput(root); + goto bail0; + } + + /* + * find the root directory's . pointer & finish filling in the inode + */ + + root_dno = hpfs_fnode_dno(s, sbi->sb_root); + if (root_dno) + de = map_dirent(root, root_dno, "\001\001", 2, NULL, &qbh); + if (!de) + hpfs_error(s, "unable to find root dir"); + else { + root->i_atime.tv_sec = local_to_gmt(s, le32_to_cpu(de->read_date)); + root->i_atime.tv_nsec = 0; + root->i_mtime.tv_sec = local_to_gmt(s, le32_to_cpu(de->write_date)); + root->i_mtime.tv_nsec = 0; + root->i_ctime.tv_sec = local_to_gmt(s, le32_to_cpu(de->creation_date)); + root->i_ctime.tv_nsec = 0; + hpfs_i(root)->i_ea_size = le16_to_cpu(de->ea_size); + hpfs_i(root)->i_parent_dir = root->i_ino; + if (root->i_size == -1) + root->i_size = 2048; + if (root->i_blocks == -1) + root->i_blocks = 5; + hpfs_brelse4(&qbh); + } + hpfs_unlock(s); + return 0; + +bail4: brelse(bh2); +bail3: brelse(bh1); +bail2: brelse(bh0); +bail1: +bail0: + hpfs_unlock(s); + kfree(sbi->sb_bmp_dir); + kfree(sbi->sb_cp_table); + s->s_fs_info = NULL; + kfree(sbi); + return -EINVAL; +} + +static struct dentry *hpfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, hpfs_fill_super); +} + +static struct file_system_type hpfs_fs_type = { + .owner = THIS_MODULE, + .name = "hpfs", + .mount = hpfs_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; + +static int __init init_hpfs_fs(void) +{ + int err = init_inodecache(); + if (err) + goto out1; + err = register_filesystem(&hpfs_fs_type); + if (err) + goto out; + return 0; +out: + destroy_inodecache(); +out1: + return err; +} + +static void __exit exit_hpfs_fs(void) +{ + unregister_filesystem(&hpfs_fs_type); + destroy_inodecache(); +} + +module_init(init_hpfs_fs) +module_exit(exit_hpfs_fs) +MODULE_LICENSE("GPL"); |