fs/bfs/inode.c

   1 /*
   2  *      fs/bfs/inode.c
   3  *      BFS superblock and inode operations.
   4  *      Copyright (C) 1999,2000 Tigran Aivazian <tigran@veritas.com>
   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 A. Aivazian <tigran@veritas.com>");
  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_blksize = PAGE_SIZE;
  80         inode->i_atime.tv_sec =  le32_to_cpu(di->i_atime);
  81         inode->i_mtime.tv_sec =  le32_to_cpu(di->i_mtime);
  82         inode->i_ctime.tv_sec =  le32_to_cpu(di->i_ctime);
  83         inode->i_atime.tv_nsec = 0;
  84         inode->i_mtime.tv_nsec = 0;
  85         inode->i_ctime.tv_nsec = 0;
  86         BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino); /* can be 0 so we store a copy */
  87
  88         brelse(bh);
  89 }
  90
  91 static int bfs_write_inode(struct inode * inode, int unused)
  92 {
  93         unsigned int ino = (u16)inode->i_ino;
  94         unsigned long i_sblock;
  95         struct bfs_inode * di;
  96         struct buffer_head * bh;
  97         int block, off;
  98
  99         dprintf("ino=%08x\n", ino);
 100
 101         if (ino < BFS_ROOT_INO || ino > BFS_SB(inode->i_sb)->si_lasti) {
 102                 printf("Bad inode number %s:%08x\n", inode->i_sb->s_id, ino);
 103                 return -EIO;
 104         }
 105
 106         lock_kernel();
 107         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
 108         bh = sb_bread(inode->i_sb, block);
 109         if (!bh) {
 110                 printf("Unable to read inode %s:%08x\n", inode->i_sb->s_id, ino);
 111                 unlock_kernel();
 112                 return -EIO;
 113         }
 114
 115         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
 116         di = (struct bfs_inode *)bh->b_data + off;
 117
 118         if (ino == BFS_ROOT_INO)
 119                 di->i_vtype = cpu_to_le32(BFS_VDIR);
 120         else
 121                 di->i_vtype = cpu_to_le32(BFS_VREG);
 122
 123         di->i_ino = cpu_to_le16(ino);
 124         di->i_mode = cpu_to_le32(inode->i_mode);
 125         di->i_uid = cpu_to_le32(inode->i_uid);
 126         di->i_gid = cpu_to_le32(inode->i_gid);
 127         di->i_nlink = cpu_to_le32(inode->i_nlink);
 128         di->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
 129         di->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
 130         di->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
 131         i_sblock = BFS_I(inode)->i_sblock;
 132         di->i_sblock = cpu_to_le32(i_sblock);
 133         di->i_eblock = cpu_to_le32(BFS_I(inode)->i_eblock);
 134         di->i_eoffset = cpu_to_le32(i_sblock * BFS_BSIZE + inode->i_size - 1);
 135
 136         mark_buffer_dirty(bh);
 137         dprintf("Written ino=%d into %d:%d\n",le16_to_cpu(di->i_ino),block,off);
 138         brelse(bh);
 139         unlock_kernel();
 140         return 0;
 141 }
 142
 143 static void bfs_delete_inode(struct inode * inode)
 144 {
 145         unsigned long ino = inode->i_ino;
 146         struct bfs_inode * di;
 147         struct buffer_head * bh;
 148         int block, off;
 149         struct super_block * s = inode->i_sb;
 150         struct bfs_sb_info * info = BFS_SB(s);
 151         struct bfs_inode_info * bi = BFS_I(inode);
 152
 153         dprintf("ino=%08lx\n", ino);
 154
 155         truncate_inode_pages(&inode->i_data, 0);
 156
 157         if (ino < BFS_ROOT_INO || ino > info->si_lasti) {
 158                 printf("invalid ino=%08lx\n", ino);
 159                 return;
 160         }
 161
 162         inode->i_size = 0;
 163         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
 164         lock_kernel();
 165         mark_inode_dirty(inode);
 166         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
 167         bh = sb_bread(s, block);
 168         if (!bh) {
 169                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id, ino);
 170                 unlock_kernel();
 171                 return;
 172         }
 173         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
 174         di = (struct bfs_inode *) bh->b_data + off;
 175         if (bi->i_dsk_ino) {
 176                 info->si_freeb += 1 + bi->i_eblock - bi->i_sblock;
 177                 info->si_freei++;
 178                 clear_bit(ino, info->si_imap);
 179                 dump_imap("delete_inode", s);
 180         }
 181         di->i_ino = 0;
 182         di->i_sblock = 0;
 183         mark_buffer_dirty(bh);
 184         brelse(bh);
 185
 186         /* if this was the last file, make the previous
 187            block "last files last block" even if there is no real file there,
 188            saves us 1 gap */
 189         if (info->si_lf_eblk == BFS_I(inode)->i_eblock) {
 190                 info->si_lf_eblk = BFS_I(inode)->i_sblock - 1;
 191                 mark_buffer_dirty(info->si_sbh);
 192         }
 193         unlock_kernel();
 194         clear_inode(inode);
 195 }
 196
 197 static void bfs_put_super(struct super_block *s)
 198 {
 199         struct bfs_sb_info *info = BFS_SB(s);
 200         brelse(info->si_sbh);
 201         kfree(info->si_imap);
 202         kfree(info);
 203         s->s_fs_info = NULL;
 204 }
 205
 206 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 207 {
 208         struct super_block *s = dentry->d_sb;
 209         struct bfs_sb_info *info = BFS_SB(s);
 210         u64 id = huge_encode_dev(s->s_bdev->bd_dev);
 211         buf->f_type = BFS_MAGIC;
 212         buf->f_bsize = s->s_blocksize;
 213         buf->f_blocks = info->si_blocks;
 214         buf->f_bfree = buf->f_bavail = info->si_freeb;
 215         buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
 216         buf->f_ffree = info->si_freei;
 217         buf->f_fsid.val[0] = (u32)id;
 218         buf->f_fsid.val[1] = (u32)(id >> 32);
 219         buf->f_namelen = BFS_NAMELEN;
 220         return 0;
 221 }
 222
 223 static void bfs_write_super(struct super_block *s)
 224 {
 225         lock_kernel();
 226         if (!(s->s_flags & MS_RDONLY))
 227                 mark_buffer_dirty(BFS_SB(s)->si_sbh);
 228         s->s_dirt = 0;
 229         unlock_kernel();
 230 }
 231
 232 static kmem_cache_t * bfs_inode_cachep;
 233
 234 static struct inode *bfs_alloc_inode(struct super_block *sb)
 235 {
 236         struct bfs_inode_info *bi;
 237         bi = kmem_cache_alloc(bfs_inode_cachep, SLAB_KERNEL);
 238         if (!bi)
 239                 return NULL;
 240         return &bi->vfs_inode;
 241 }
 242
 243 static void bfs_destroy_inode(struct inode *inode)
 244 {
 245         kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
 246 }
 247
 248 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
 249 {
 250         struct bfs_inode_info *bi = foo;
 251
 252         if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
 253             SLAB_CTOR_CONSTRUCTOR)
 254                 inode_init_once(&bi->vfs_inode);
 255 }
 256
 257 static int init_inodecache(void)
 258 {
 259         bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
 260                                              sizeof(struct bfs_inode_info),
 261                                              0, (SLAB_RECLAIM_ACCOUNT|
 262                                                 SLAB_MEM_SPREAD),
 263                                              init_once, NULL);
 264         if (bfs_inode_cachep == NULL)
 265                 return -ENOMEM;
 266         return 0;
 267 }
 268
 269 static void destroy_inodecache(void)
 270 {
 271         if (kmem_cache_destroy(bfs_inode_cachep))
 272                 printk(KERN_INFO "bfs_inode_cache: not all structures were freed\n");
 273 }
 274
 275 static struct super_operations bfs_sops = {
 276         .alloc_inode    = bfs_alloc_inode,
 277         .destroy_inode  = bfs_destroy_inode,
 278         .read_inode     = bfs_read_inode,
 279         .write_inode    = bfs_write_inode,
 280         .delete_inode   = bfs_delete_inode,
 281         .put_super      = bfs_put_super,
 282         .write_super    = bfs_write_super,
 283         .statfs         = bfs_statfs,
 284 };
 285
 286 void dump_imap(const char *prefix, struct super_block * s)
 287 {
 288 #ifdef DEBUG
 289         int i;
 290         char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
 291
 292         if (!tmpbuf)
 293                 return;
 294         for (i=BFS_SB(s)->si_lasti; i>=0; i--) {
 295                 if (i > PAGE_SIZE-100) break;
 296                 if (test_bit(i, BFS_SB(s)->si_imap))
 297                         strcat(tmpbuf, "1");
 298                 else
 299                         strcat(tmpbuf, "0");
 300         }
 301         printk(KERN_ERR "BFS-fs: %s: lasti=%08lx <%s>\n", prefix, BFS_SB(s)->si_lasti, tmpbuf);
 302         free_page((unsigned long)tmpbuf);
 303 #endif
 304 }
 305
 306 static int bfs_fill_super(struct super_block *s, void *data, int silent)
 307 {
 308         struct buffer_head * bh;
 309         struct bfs_super_block * bfs_sb;
 310         struct inode * inode;
 311         unsigned i, imap_len;
 312         struct bfs_sb_info * info;
 313
 314         info = kzalloc(sizeof(*info), GFP_KERNEL);
 315         if (!info)
 316                 return -ENOMEM;
 317         s->s_fs_info = info;
 318
 319         sb_set_blocksize(s, BFS_BSIZE);
 320
 321         bh = sb_bread(s, 0);
 322         if(!bh)
 323                 goto out;
 324         bfs_sb = (struct bfs_super_block *)bh->b_data;
 325         if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
 326                 if (!silent)
 327                         printf("No BFS filesystem on %s (magic=%08x)\n",
 328                                 s->s_id,  le32_to_cpu(bfs_sb->s_magic));
 329                 goto out;
 330         }
 331         if (BFS_UNCLEAN(bfs_sb, s) && !silent)
 332                 printf("%s is unclean, continuing\n", s->s_id);
 333
 334         s->s_magic = BFS_MAGIC;
 335         info->si_sbh = bh;
 336         info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE)/sizeof(struct bfs_inode)
 337                         + BFS_ROOT_INO - 1;
 338
 339         imap_len = info->si_lasti/8 + 1;
 340         info->si_imap = kzalloc(imap_len, GFP_KERNEL);
 341         if (!info->si_imap)
 342                 goto out;
 343         for (i=0; i<BFS_ROOT_INO; i++)
 344                 set_bit(i, info->si_imap);
 345
 346         s->s_op = &bfs_sops;
 347         inode = iget(s, BFS_ROOT_INO);
 348         if (!inode) {
 349                 kfree(info->si_imap);
 350                 goto out;
 351         }
 352         s->s_root = d_alloc_root(inode);
 353         if (!s->s_root) {
 354                 iput(inode);
 355                 kfree(info->si_imap);
 356                 goto out;
 357         }
 358
 359         info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
 360         info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1 -  le32_to_cpu(bfs_sb->s_start))>>BFS_BSIZE_BITS;
 361         info->si_freei = 0;
 362         info->si_lf_eblk = 0;
 363         info->si_lf_sblk = 0;
 364         info->si_lf_ioff = 0;
 365         bh = NULL;
 366         for (i=BFS_ROOT_INO; i<=info->si_lasti; i++) {
 367                 struct bfs_inode *di;
 368                 int block = (i - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
 369                 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
 370                 unsigned long sblock, eblock;
 371
 372                 if (!off) {
 373                         brelse(bh);
 374                         bh = sb_bread(s, block);
 375                 }
 376
 377                 if (!bh)
 378                         continue;
 379
 380                 di = (struct bfs_inode *)bh->b_data + off;
 381
 382                 if (!di->i_ino) {
 383                         info->si_freei++;
 384                         continue;
 385                 }
 386                 set_bit(i, info->si_imap);
 387                 info->si_freeb -= BFS_FILEBLOCKS(di);
 388
 389                 sblock =  le32_to_cpu(di->i_sblock);
 390                 eblock =  le32_to_cpu(di->i_eblock);
 391                 if (eblock > info->si_lf_eblk) {
 392                         info->si_lf_eblk = eblock;
 393                         info->si_lf_sblk = sblock;
 394                         info->si_lf_ioff = BFS_INO2OFF(i);
 395                 }
 396         }
 397         brelse(bh);
 398         if (!(s->s_flags & MS_RDONLY)) {
 399                 mark_buffer_dirty(info->si_sbh);
 400                 s->s_dirt = 1;
 401         }
 402         dump_imap("read_super", s);
 403         return 0;
 404
 405 out:
 406         brelse(bh);
 407         kfree(info);
 408         s->s_fs_info = NULL;
 409         return -EINVAL;
 410 }
 411
 412 static int bfs_get_sb(struct file_system_type *fs_type,
 413         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 414 {
 415         return get_sb_bdev(fs_type, flags, dev_name, data, bfs_fill_super, mnt);
 416 }
 417
 418 static struct file_system_type bfs_fs_type = {
 419         .owner          = THIS_MODULE,
 420         .name           = "bfs",
 421         .get_sb         = bfs_get_sb,
 422         .kill_sb        = kill_block_super,
 423         .fs_flags       = FS_REQUIRES_DEV,
 424 };
 425
 426 static int __init init_bfs_fs(void)
 427 {
 428         int err = init_inodecache();
 429         if (err)
 430                 goto out1;
 431         err = register_filesystem(&bfs_fs_type);
 432         if (err)
 433                 goto out;
 434         return 0;
 435 out:
 436         destroy_inodecache();
 437 out1:
 438         return err;
 439 }
 440
 441 static void __exit exit_bfs_fs(void)
 442 {
 443         unregister_filesystem(&bfs_fs_type);
 444         destroy_inodecache();
 445 }
 446
 447 module_init(init_bfs_fs)
 448 module_exit(exit_bfs_fs)