fs/bfs/inode.c

   1 /*
   2  *      fs/bfs/inode.c
   3  *      BFS superblock and inode operations.
   4  *      Copyright (C) 1999-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
   5  *      From fs/minix, Copyright (C) 1991, 1992 Linus Torvalds.
   6  *
   7  *      Made endianness-clean by Andrew Stribblehill <ads@wompom.org>, 2005.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/mm.h>
  12 #include <linux/slab.h>
  13 #include <linux/init.h>
  14 #include <linux/fs.h>
  15 #include <linux/smp_lock.h>
  16 #include <linux/buffer_head.h>
  17 #include <linux/vfs.h>
  18 #include <asm/uaccess.h>
  19 #include "bfs.h"
  20
  21 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
  22 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
  23 MODULE_LICENSE("GPL");
  24
  25 #undef DEBUG
  26
  27 #ifdef DEBUG
  28 #define dprintf(x...)   printf(x)
  29 #else
  30 #define dprintf(x...)
  31 #endif
  32
  33 void dump_imap(const char *prefix, struct super_block * s);
  34
  35 static void bfs_read_inode(struct inode * inode)
  36 {
  37         unsigned long ino = inode->i_ino;
  38         struct bfs_inode * di;
  39         struct buffer_head * bh;
  40         int block, off;
  41
  42         if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
  43                 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
  44                 make_bad_inode(inode);
  45                 return;
  46         }
  47
  48         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
  49         bh = sb_bread(inode->i_sb, block);
  50         if (!bh) {
  51                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
  52                 make_bad_inode(inode);
  53                 return;
  54         }
  55
  56         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
  57         di = (struct bfs_inode *)bh->b_data + off;
  58
  59         inode->i_mode = 0x0000FFFF &  le32_to_cpu(di->i_mode);
  60         if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
  61                 inode->i_mode |= S_IFDIR;
  62                 inode->i_op = &bfs_dir_inops;
  63                 inode->i_fop = &bfs_dir_operations;
  64         } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
  65                 inode->i_mode |= S_IFREG;
  66                 inode->i_op = &bfs_file_inops;
  67                 inode->i_fop = &bfs_file_operations;
  68                 inode->i_mapping->a_ops = &bfs_aops;
  69         }
  70
  71         BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
  72         BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
  73         inode->i_uid =  le32_to_cpu(di->i_uid);
  74         inode->i_gid =  le32_to_cpu(di->i_gid);
  75         inode->i_nlink =  le32_to_cpu(di->i_nlink);
  76         inode->i_size = BFS_FILESIZE(di);
  77         inode->i_blocks = BFS_FILEBLOCKS(di);
  78         if (inode->i_size || inode->i_blocks) dprintf("Registered inode with %lld size, %ld blocks\n", inode->i_size, inode->i_blocks);
  79         inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
  80         inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
  81         inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
  82         inode->i_atime.tv_nsec = 0;
  83         inode->i_mtime.tv_nsec = 0;
  84         inode->i_ctime.tv_nsec = 0;
  85         BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); /* can be 0 so we store a copy */
  86
  87         brelse(bh);
  88 }
  89
  90 static int bfs_write_inode(struct inode * inode, int unused)
  91 {
  92         unsigned int ino = (u16)inode->i_ino;
  93         unsigned long i_sblock;
  94         struct bfs_inode * di;
  95         struct buffer_head * bh;
  96         int block, off;
  97
  98         dprintf("ino=%08x\n", ino);
  99
 100         if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
 101                 printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
 102                 return -EIO;
 103         }
 104
 105         lock_kernel();
 106         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
 107         bh = sb_bread(inode->i_sb, block);
 108         if (!bh) {
 109                 printf("Unable to read inode %s:%08x\n", inode->i_sb->s_id, ino);
 110                 unlock_kernel();
 111                 return -EIO;
 112         }
 113
 114         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
 115         di = (struct bfs_inode *)bh->b_data + off;
 116
 117         if (ino == BFS_ROOT_INO)
 118                 di->i_vtype = cpu_to_le32(BFS_VDIR);
 119         else
 120                 di->i_vtype = cpu_to_le32(BFS_VREG);
 121
 122         di->i_ino = cpu_to_le16(ino);
 123         di->i_mode = cpu_to_le32(inode->i_mode);
 124         di->i_uid = cpu_to_le32(inode->i_uid);
 125         di->i_gid = cpu_to_le32(inode->i_gid);
 126         di->i_nlink = cpu_to_le32(inode->i_nlink);
 127         di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
 128         di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
 129         di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
 130         i_sblock = BFS_I(inode)->i_sblock;
 131         di->i_sblock = cpu_to_le32(i_sblock);
 132         di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
 133         di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
 134
 135         mark_buffer_dirty(bh);
 136         dprintf("Written ino=%d into %d:%d\n",le16_to_cpu(di->i_ino),block,off);
 137         brelse(bh);
 138         unlock_kernel();
 139         return 0;
 140 }
 141
 142 static void bfs_delete_inode(struct inode * inode)
 143 {
 144         unsigned long ino = inode->i_ino;
 145         struct bfs_inode * di;
 146         struct buffer_head * bh;
 147         int block, off;
 148         struct super_block * s = inode->i_sb;
 149         struct bfs_sb_info * info = BFS_SB(s);
 150         struct bfs_inode_info * bi = BFS_I(inode);
 151
 152         dprintf("ino=%08lx\n", ino);
 153
 154         truncate_inode_pages(&inode->i_data, 0);
 155
 156         if (ino < BFS_ROOT_INO || ino > info->si_lasti) {
 157                 printf("invalid ino=%08lx\n", ino);
 158                 return;
 159         }
 160
 161         inode->i_size = 0;
 162         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
 163         lock_kernel();
 164         mark_inode_dirty(inode);
 165         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
 166         bh = sb_bread(s, block);
 167         if (!bh) {
 168                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
 169                 unlock_kernel();
 170                 return;
 171         }
 172         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
 173         di = (struct bfs_inode *) bh->b_data + off;
 174         if (bi->i_dsk_ino) {
 175                 info->si_freeb += 1 + bi->i_eblock - bi->i_sblock;
 176                 info->si_freei++;
 177                 clear_bit(ino, info->si_imap);
 178                 dump_imap("delete_inode", s);
 179         }
 180         di->i_ino = 0;
 181         di->i_sblock = 0;
 182         mark_buffer_dirty(bh);
 183         brelse(bh);
 184
 185         /* if this was the last file, make the previous
 186            block "last files last block" even if there is no real file there,
 187            saves us 1 gap */
 188         if (info->si_lf_eblk == BFS_I(inode)->i_eblock) {
 189                 info->si_lf_eblk = BFS_I(inode)->i_sblock - 1;
 190                 mark_buffer_dirty(info->si_sbh);
 191         }
 192         unlock_kernel();
 193         clear_inode(inode);
 194 }
 195
 196 static void bfs_put_super(struct super_block *s)
 197 {
 198         struct bfs_sb_info *info = BFS_SB(s);
 199         brelse(info->si_sbh);
 200         kfree(info->si_imap);
 201         kfree(info);
 202         s->s_fs_info = NULL;
 203 }
 204
 205 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 206 {
 207         struct super_block *s = dentry->d_sb;
 208         struct bfs_sb_info *info = BFS_SB(s);
 209         u64 id = huge_encode_dev(s->s_bdev->bd_dev);
 210         buf->f_type = BFS_MAGIC;
 211         buf->f_bsize = s->s_blocksize;
 212         buf->f_blocks = info->si_blocks;
 213         buf->f_bfree = buf->f_bavail = info->si_freeb;
 214         buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
 215         buf->f_ffree = info->si_freei;
 216         buf->f_fsid.val[0] = (u32)id;
 217         buf->f_fsid.val[1] = (u32)(id >> 32);
 218         buf->f_namelen = BFS_NAMELEN;
 219         return 0;
 220 }
 221
 222 static void bfs_write_super(struct super_block *s)
 223 {
 224         lock_kernel();
 225         if (!(s->s_flags & MS_RDONLY))
 226                 mark_buffer_dirty(BFS_SB(s)->si_sbh);
 227         s->s_dirt = 0;
 228         unlock_kernel();
 229 }
 230
 231 static struct kmem_cache * bfs_inode_cachep;
 232
 233 static struct inode *bfs_alloc_inode(struct super_block *sb)
 234 {
 235         struct bfs_inode_info *bi;
 236         bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
 237         if (!bi)
 238                 return NULL;
 239         return &bi->vfs_inode;
 240 }
 241
 242 static void bfs_destroy_inode(struct inode *inode)
 243 {
 244         kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
 245 }
 246
 247 static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
 248 {
 249         struct bfs_inode_info *bi = foo;
 250
 251         if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
 252             SLAB_CTOR_CONSTRUCTOR)
 253                 inode_init_once(&bi->vfs_inode);
 254 }
 255
 256 static int init_inodecache(void)
 257 {
 258         bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
 259                                              sizeof(struct bfs_inode_info),
 260                                              0, (SLAB_RECLAIM_ACCOUNT|
 261                                                 SLAB_MEM_SPREAD),
 262                                              init_once, NULL);
 263         if (bfs_inode_cachep == NULL)
 264                 return -ENOMEM;
 265         return 0;
 266 }
 267
 268 static void destroy_inodecache(void)
 269 {
 270         kmem_cache_destroy(bfs_inode_cachep);
 271 }
 272
 273 static const struct super_operations bfs_sops = {
 274         .alloc_inode    = bfs_alloc_inode,
 275         .destroy_inode  = bfs_destroy_inode,
 276         .read_inode     = bfs_read_inode,
 277         .write_inode    = bfs_write_inode,
 278         .delete_inode   = bfs_delete_inode,
 279         .put_super      = bfs_put_super,
 280         .write_super    = bfs_write_super,
 281         .statfs         = bfs_statfs,
 282 };
 283
 284 void dump_imap(const char *prefix, struct super_block * s)
 285 {
 286 #ifdef DEBUG
 287         int i;
 288         char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
 289
 290         if (!tmpbuf)
 291                 return;
 292         for (i=BFS_SB(s)->si_lasti; i>=0; i--) {
 293                 if (i > PAGE_SIZE-100) break;
 294                 if (test_bit(i, BFS_SB(s)->si_imap))
 295                         strcat(tmpbuf, "1");
 296                 else
 297                         strcat(tmpbuf, "0");
 298         }
 299         printk(KERN_ERR "BFS-fs: %s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
 300         free_page((unsigned long)tmpbuf);
 301 #endif
 302 }
 303
 304 static int bfs_fill_super(struct super_block *s, void *data, int silent)
 305 {
 306         struct buffer_head * bh;
 307         struct bfs_super_block * bfs_sb;
 308         struct inode * inode;
 309         unsigned i, imap_len;
 310         struct bfs_sb_info * info;
 311
 312         info = kzalloc(sizeof(*info), GFP_KERNEL);
 313         if (!info)
 314                 return -ENOMEM;
 315         s->s_fs_info = info;
 316
 317         sb_set_blocksize(s, BFS_BSIZE);
 318
 319         bh = sb_bread(s, 0);
 320         if(!bh)
 321                 goto out;
 322         bfs_sb = (struct bfs_super_block *)bh->b_data;
 323         if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
 324                 if (!silent)
 325                         printf("No BFS filesystem on %s (magic=%08x)\n",
 326                                 s->s_id,  le32_to_cpu(bfs_sb->s_magic));
 327                 goto out;
 328         }
 329         if (BFS_UNCLEAN(bfs_sb, s) && !silent)
 330                 printf("%s is unclean, continuing\n", s->s_id);
 331
 332         s->s_magic = BFS_MAGIC;
 333         info->si_sbh = bh;
 334         info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE)/sizeof(struct bfs_inode)
 335                         + BFS_ROOT_INO - 1;
 336
 337         imap_len = info->si_lasti/8 + 1;
 338         info->si_imap = kzalloc(imap_len, GFP_KERNEL);
 339         if (!info->si_imap)
 340                 goto out;
 341         for (i=0; i<BFS_ROOT_INO; i++)
 342                 set_bit(i, info->si_imap);
 343
 344         s->s_op = &bfs_sops;
 345         inode = iget(s, BFS_ROOT_INO);
 346         if (!inode) {
 347                 kfree(info->si_imap);
 348                 goto out;
 349         }
 350         s->s_root = d_alloc_root(inode);
 351         if (!s->s_root) {
 352                 iput(inode);
 353                 kfree(info->si_imap);
 354                 goto out;
 355         }
 356
 357         info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
 358         info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 -  le32_to_cpu(bfs_sb->s_start))>>BFS_BSIZE_BITS;
 359         info->si_freei = 0;
 360         info->si_lf_eblk = 0;
 361         info->si_lf_sblk = 0;
 362         info->si_lf_ioff = 0;
 363         bh = NULL;
 364         for (i=BFS_ROOT_INO; i<=info->si_lasti; i++) {
 365                 struct bfs_inode *di;
 366                 int block = (i - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
 367                 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
 368                 unsigned long sblock, eblock;
 369
 370                 if (!off) {
 371                         brelse(bh);
 372                         bh = sb_bread(s, block);
 373                 }
 374
 375                 if (!bh)
 376                         continue;
 377
 378                 di = (struct bfs_inode *)bh->b_data + off;
 379
 380                 if (!di->i_ino) {
 381                         info->si_freei++;
 382                         continue;
 383                 }
 384                 set_bit(i, info->si_imap);
 385                 info->si_freeb -= BFS_FILEBLOCKS(di);
 386
 387                 sblock =  le32_to_cpu(di->i_sblock);
 388                 eblock =  le32_to_cpu(di->i_eblock);
 389                 if (eblock > info->si_lf_eblk) {
 390                         info->si_lf_eblk = eblock;
 391                         info->si_lf_sblk = sblock;
 392                         info->si_lf_ioff = BFS_INO2OFF(i);
 393                 }
 394         }
 395         brelse(bh);
 396         if (!(s->s_flags & MS_RDONLY)) {
 397                 mark_buffer_dirty(info->si_sbh);
 398                 s->s_dirt = 1;
 399         }
 400         dump_imap("read_super", s);
 401         return 0;
 402
 403 out:
 404         brelse(bh);
 405         kfree(info);
 406         s->s_fs_info = NULL;
 407         return -EINVAL;
 408 }
 409
 410 static int bfs_get_sb(struct file_system_type *fs_type,
 411         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 412 {
 413         return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
 414 }
 415
 416 static struct file_system_type bfs_fs_type = {
 417         .owner          = THIS_MODULE,
 418         .name           = "bfs",
 419         .get_sb         = bfs_get_sb,
 420         .kill_sb        = kill_block_super,
 421         .fs_flags       = FS_REQUIRES_DEV,
 422 };
 423
 424 static int __init init_bfs_fs(void)
 425 {
 426         int err = init_inodecache();
 427         if (err)
 428                 goto out1;
 429         err = register_filesystem(&bfs_fs_type);
 430         if (err)
 431                 goto out;
 432         return 0;
 433 out:
 434         destroy_inodecache();
 435 out1:
 436         return err;
 437 }
 438
 439 static void __exit exit_bfs_fs(void)
 440 {
 441         unregister_filesystem(&bfs_fs_type);
 442         destroy_inodecache();
 443 }
 444
 445 module_init(init_bfs_fs)
 446 module_exit(exit_bfs_fs)