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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/adfs/super.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/adfs/super.c')
-rw-r--r-- | fs/adfs/super.c | 508 |
1 files changed, 508 insertions, 0 deletions
diff --git a/fs/adfs/super.c b/fs/adfs/super.c new file mode 100644 index 000000000000..243963228d10 --- /dev/null +++ b/fs/adfs/super.c @@ -0,0 +1,508 @@ +/* + * linux/fs/adfs/super.c + * + * Copyright (C) 1997-1999 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/adfs_fs.h> +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/stat.h> +#include <linux/string.h> +#include <linux/init.h> +#include <linux/buffer_head.h> +#include <linux/vfs.h> +#include <linux/parser.h> +#include <linux/bitops.h> + +#include <asm/uaccess.h> +#include <asm/system.h> + +#include <stdarg.h> + +#include "adfs.h" +#include "dir_f.h" +#include "dir_fplus.h" + +void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...) +{ + char error_buf[128]; + va_list args; + + va_start(args, fmt); + vsprintf(error_buf, fmt, args); + va_end(args); + + printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %s\n", + sb->s_id, function ? ": " : "", + function ? function : "", error_buf); +} + +static int adfs_checkdiscrecord(struct adfs_discrecord *dr) +{ + int i; + + /* sector size must be 256, 512 or 1024 bytes */ + if (dr->log2secsize != 8 && + dr->log2secsize != 9 && + dr->log2secsize != 10) + return 1; + + /* idlen must be at least log2secsize + 3 */ + if (dr->idlen < dr->log2secsize + 3) + return 1; + + /* we cannot have such a large disc that we + * are unable to represent sector offsets in + * 32 bits. This works out at 2.0 TB. + */ + if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize) + return 1; + + /* idlen must be no greater than 19 v2 [1.0] */ + if (dr->idlen > 19) + return 1; + + /* reserved bytes should be zero */ + for (i = 0; i < sizeof(dr->unused52); i++) + if (dr->unused52[i] != 0) + return 1; + + return 0; +} + +static unsigned char adfs_calczonecheck(struct super_block *sb, unsigned char *map) +{ + unsigned int v0, v1, v2, v3; + int i; + + v0 = v1 = v2 = v3 = 0; + for (i = sb->s_blocksize - 4; i; i -= 4) { + v0 += map[i] + (v3 >> 8); + v3 &= 0xff; + v1 += map[i + 1] + (v0 >> 8); + v0 &= 0xff; + v2 += map[i + 2] + (v1 >> 8); + v1 &= 0xff; + v3 += map[i + 3] + (v2 >> 8); + v2 &= 0xff; + } + v0 += v3 >> 8; + v1 += map[1] + (v0 >> 8); + v2 += map[2] + (v1 >> 8); + v3 += map[3] + (v2 >> 8); + + return v0 ^ v1 ^ v2 ^ v3; +} + +static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm) +{ + unsigned char crosscheck = 0, zonecheck = 1; + int i; + + for (i = 0; i < ADFS_SB(sb)->s_map_size; i++) { + unsigned char *map; + + map = dm[i].dm_bh->b_data; + + if (adfs_calczonecheck(sb, map) != map[0]) { + adfs_error(sb, "zone %d fails zonecheck", i); + zonecheck = 0; + } + crosscheck ^= map[3]; + } + if (crosscheck != 0xff) + adfs_error(sb, "crosscheck != 0xff"); + return crosscheck == 0xff && zonecheck; +} + +static void adfs_put_super(struct super_block *sb) +{ + int i; + struct adfs_sb_info *asb = ADFS_SB(sb); + + for (i = 0; i < asb->s_map_size; i++) + brelse(asb->s_map[i].dm_bh); + kfree(asb->s_map); + kfree(asb); + sb->s_fs_info = NULL; +} + +enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_err}; + +static match_table_t tokens = { + {Opt_uid, "uid=%u"}, + {Opt_gid, "gid=%u"}, + {Opt_ownmask, "ownmask=%o"}, + {Opt_othmask, "othmask=%o"}, + {Opt_err, NULL} +}; + +static int parse_options(struct super_block *sb, char *options) +{ + char *p; + struct adfs_sb_info *asb = ADFS_SB(sb); + int option; + + if (!options) + return 0; + + while ((p = strsep(&options, ",")) != NULL) { + substring_t args[MAX_OPT_ARGS]; + int token; + if (!*p) + continue; + + token = match_token(p, tokens, args); + switch (token) { + case Opt_uid: + if (match_int(args, &option)) + return -EINVAL; + asb->s_uid = option; + break; + case Opt_gid: + if (match_int(args, &option)) + return -EINVAL; + asb->s_gid = option; + break; + case Opt_ownmask: + if (match_octal(args, &option)) + return -EINVAL; + asb->s_owner_mask = option; + break; + case Opt_othmask: + if (match_octal(args, &option)) + return -EINVAL; + asb->s_other_mask = option; + break; + default: + printk("ADFS-fs: unrecognised mount option \"%s\" " + "or missing value\n", p); + return -EINVAL; + } + } + return 0; +} + +static int adfs_remount(struct super_block *sb, int *flags, char *data) +{ + *flags |= MS_NODIRATIME; + return parse_options(sb, data); +} + +static int adfs_statfs(struct super_block *sb, struct kstatfs *buf) +{ + struct adfs_sb_info *asb = ADFS_SB(sb); + + buf->f_type = ADFS_SUPER_MAGIC; + buf->f_namelen = asb->s_namelen; + buf->f_bsize = sb->s_blocksize; + buf->f_blocks = asb->s_size; + buf->f_files = asb->s_ids_per_zone * asb->s_map_size; + buf->f_bavail = + buf->f_bfree = adfs_map_free(sb); + buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks; + + return 0; +} + +static kmem_cache_t *adfs_inode_cachep; + +static struct inode *adfs_alloc_inode(struct super_block *sb) +{ + struct adfs_inode_info *ei; + ei = (struct adfs_inode_info *)kmem_cache_alloc(adfs_inode_cachep, SLAB_KERNEL); + if (!ei) + return NULL; + return &ei->vfs_inode; +} + +static void adfs_destroy_inode(struct inode *inode) +{ + kmem_cache_free(adfs_inode_cachep, ADFS_I(inode)); +} + +static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) +{ + struct adfs_inode_info *ei = (struct adfs_inode_info *) foo; + + if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == + SLAB_CTOR_CONSTRUCTOR) + inode_init_once(&ei->vfs_inode); +} + +static int init_inodecache(void) +{ + adfs_inode_cachep = kmem_cache_create("adfs_inode_cache", + sizeof(struct adfs_inode_info), + 0, SLAB_RECLAIM_ACCOUNT, + init_once, NULL); + if (adfs_inode_cachep == NULL) + return -ENOMEM; + return 0; +} + +static void destroy_inodecache(void) +{ + if (kmem_cache_destroy(adfs_inode_cachep)) + printk(KERN_INFO "adfs_inode_cache: not all structures were freed\n"); +} + +static struct super_operations adfs_sops = { + .alloc_inode = adfs_alloc_inode, + .destroy_inode = adfs_destroy_inode, + .write_inode = adfs_write_inode, + .put_super = adfs_put_super, + .statfs = adfs_statfs, + .remount_fs = adfs_remount, +}; + +static struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr) +{ + struct adfs_discmap *dm; + unsigned int map_addr, zone_size, nzones; + int i, zone; + struct adfs_sb_info *asb = ADFS_SB(sb); + + nzones = asb->s_map_size; + zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare); + map_addr = (nzones >> 1) * zone_size - + ((nzones > 1) ? ADFS_DR_SIZE_BITS : 0); + map_addr = signed_asl(map_addr, asb->s_map2blk); + + asb->s_ids_per_zone = zone_size / (asb->s_idlen + 1); + + dm = kmalloc(nzones * sizeof(*dm), GFP_KERNEL); + if (dm == NULL) { + adfs_error(sb, "not enough memory"); + return NULL; + } + + for (zone = 0; zone < nzones; zone++, map_addr++) { + dm[zone].dm_startbit = 0; + dm[zone].dm_endbit = zone_size; + dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS; + dm[zone].dm_bh = sb_bread(sb, map_addr); + + if (!dm[zone].dm_bh) { + adfs_error(sb, "unable to read map"); + goto error_free; + } + } + + /* adjust the limits for the first and last map zones */ + i = zone - 1; + dm[0].dm_startblk = 0; + dm[0].dm_startbit = ADFS_DR_SIZE_BITS; + dm[i].dm_endbit = (le32_to_cpu(dr->disc_size_high) << (32 - dr->log2bpmb)) + + (le32_to_cpu(dr->disc_size) >> dr->log2bpmb) + + (ADFS_DR_SIZE_BITS - i * zone_size); + + if (adfs_checkmap(sb, dm)) + return dm; + + adfs_error(sb, NULL, "map corrupted"); + +error_free: + while (--zone >= 0) + brelse(dm[zone].dm_bh); + + kfree(dm); + return NULL; +} + +static inline unsigned long adfs_discsize(struct adfs_discrecord *dr, int block_bits) +{ + unsigned long discsize; + + discsize = le32_to_cpu(dr->disc_size_high) << (32 - block_bits); + discsize |= le32_to_cpu(dr->disc_size) >> block_bits; + + return discsize; +} + +static int adfs_fill_super(struct super_block *sb, void *data, int silent) +{ + struct adfs_discrecord *dr; + struct buffer_head *bh; + struct object_info root_obj; + unsigned char *b_data; + struct adfs_sb_info *asb; + struct inode *root; + + sb->s_flags |= MS_NODIRATIME; + + asb = kmalloc(sizeof(*asb), GFP_KERNEL); + if (!asb) + return -ENOMEM; + sb->s_fs_info = asb; + memset(asb, 0, sizeof(*asb)); + + /* set default options */ + asb->s_uid = 0; + asb->s_gid = 0; + asb->s_owner_mask = S_IRWXU; + asb->s_other_mask = S_IRWXG | S_IRWXO; + + if (parse_options(sb, data)) + goto error; + + sb_set_blocksize(sb, BLOCK_SIZE); + if (!(bh = sb_bread(sb, ADFS_DISCRECORD / BLOCK_SIZE))) { + adfs_error(sb, "unable to read superblock"); + goto error; + } + + b_data = bh->b_data + (ADFS_DISCRECORD % BLOCK_SIZE); + + if (adfs_checkbblk(b_data)) { + if (!silent) + printk("VFS: Can't find an adfs filesystem on dev " + "%s.\n", sb->s_id); + goto error_free_bh; + } + + dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET); + + /* + * Do some sanity checks on the ADFS disc record + */ + if (adfs_checkdiscrecord(dr)) { + if (!silent) + printk("VPS: Can't find an adfs filesystem on dev " + "%s.\n", sb->s_id); + goto error_free_bh; + } + + brelse(bh); + if (sb_set_blocksize(sb, 1 << dr->log2secsize)) { + bh = sb_bread(sb, ADFS_DISCRECORD / sb->s_blocksize); + if (!bh) { + adfs_error(sb, "couldn't read superblock on " + "2nd try."); + goto error; + } + b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize); + if (adfs_checkbblk(b_data)) { + adfs_error(sb, "disc record mismatch, very weird!"); + goto error_free_bh; + } + dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET); + } else { + if (!silent) + printk(KERN_ERR "VFS: Unsupported blocksize on dev " + "%s.\n", sb->s_id); + goto error; + } + + /* + * blocksize on this device should now be set to the ADFS log2secsize + */ + + sb->s_magic = ADFS_SUPER_MAGIC; + asb->s_idlen = dr->idlen; + asb->s_map_size = dr->nzones | (dr->nzones_high << 8); + asb->s_map2blk = dr->log2bpmb - dr->log2secsize; + asb->s_size = adfs_discsize(dr, sb->s_blocksize_bits); + asb->s_version = dr->format_version; + asb->s_log2sharesize = dr->log2sharesize; + + asb->s_map = adfs_read_map(sb, dr); + if (!asb->s_map) + goto error_free_bh; + + brelse(bh); + + /* + * set up enough so that we can read an inode + */ + sb->s_op = &adfs_sops; + + dr = (struct adfs_discrecord *)(asb->s_map[0].dm_bh->b_data + 4); + + root_obj.parent_id = root_obj.file_id = le32_to_cpu(dr->root); + root_obj.name_len = 0; + root_obj.loadaddr = 0; + root_obj.execaddr = 0; + root_obj.size = ADFS_NEWDIR_SIZE; + root_obj.attr = ADFS_NDA_DIRECTORY | ADFS_NDA_OWNER_READ | + ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ; + + /* + * If this is a F+ disk with variable length directories, + * get the root_size from the disc record. + */ + if (asb->s_version) { + root_obj.size = le32_to_cpu(dr->root_size); + asb->s_dir = &adfs_fplus_dir_ops; + asb->s_namelen = ADFS_FPLUS_NAME_LEN; + } else { + asb->s_dir = &adfs_f_dir_ops; + asb->s_namelen = ADFS_F_NAME_LEN; + } + + root = adfs_iget(sb, &root_obj); + sb->s_root = d_alloc_root(root); + if (!sb->s_root) { + int i; + iput(root); + for (i = 0; i < asb->s_map_size; i++) + brelse(asb->s_map[i].dm_bh); + kfree(asb->s_map); + adfs_error(sb, "get root inode failed\n"); + goto error; + } else + sb->s_root->d_op = &adfs_dentry_operations; + return 0; + +error_free_bh: + brelse(bh); +error: + sb->s_fs_info = NULL; + kfree(asb); + return -EINVAL; +} + +static struct super_block *adfs_get_sb(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return get_sb_bdev(fs_type, flags, dev_name, data, adfs_fill_super); +} + +static struct file_system_type adfs_fs_type = { + .owner = THIS_MODULE, + .name = "adfs", + .get_sb = adfs_get_sb, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; + +static int __init init_adfs_fs(void) +{ + int err = init_inodecache(); + if (err) + goto out1; + err = register_filesystem(&adfs_fs_type); + if (err) + goto out; + return 0; +out: + destroy_inodecache(); +out1: + return err; +} + +static void __exit exit_adfs_fs(void) +{ + unregister_filesystem(&adfs_fs_type); + destroy_inodecache(); +} + +module_init(init_adfs_fs) +module_exit(exit_adfs_fs) |