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,
  52                                                                         ino);
  53                 make_bad_inode(inode);
  54                 return;
  55         }
  56
  57         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
  58         di = (struct bfs_inode *)bh->b_data + off;
  59
  60         inode->i_mode = 0x0000FFFF & le32_to_cpu(di->i_mode);
  61         if (le32_to_cpu(di->i_vtype) == BFS_VDIR) {
  62                 inode->i_mode |= S_IFDIR;
  63                 inode->i_op = &bfs_dir_inops;
  64                 inode->i_fop = &bfs_dir_operations;
  65         } else if (le32_to_cpu(di->i_vtype) == BFS_VREG) {
  66                 inode->i_mode |= S_IFREG;
  67                 inode->i_op = &bfs_file_inops;
  68                 inode->i_fop = &bfs_file_operations;
  69                 inode->i_mapping->a_ops = &bfs_aops;
  70         }
  71
  72         BFS_I(inode)->i_sblock =  le32_to_cpu(di->i_sblock);
  73         BFS_I(inode)->i_eblock =  le32_to_cpu(di->i_eblock);
  74         BFS_I(inode)->i_dsk_ino = le16_to_cpu(di->i_ino);
  75         inode->i_uid =  le32_to_cpu(di->i_uid);
  76         inode->i_gid =  le32_to_cpu(di->i_gid);
  77         inode->i_nlink =  le32_to_cpu(di->i_nlink);
  78         inode->i_size = BFS_FILESIZE(di);
  79         inode->i_blocks = BFS_FILEBLOCKS(di);
  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
  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",
 110                                 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         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
 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",
 170                                         inode->i_sb->s_id, ino);
 171                 unlock_kernel();
 172                 return;
 173         }
 174         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
 175         di = (struct bfs_inode *)bh->b_data + off;
 176         memset((void *)di, 0, sizeof(struct bfs_inode));
 177         mark_buffer_dirty(bh);
 178         brelse(bh);
 179
 180         if (bi->i_dsk_ino) {
 181                 if (bi->i_sblock)
 182                         info->si_freeb += bi->i_eblock + 1 - bi->i_sblock;
 183                 info->si_freei++;
 184                 clear_bit(ino, info->si_imap);
 185                 dump_imap("delete_inode", s);
 186         }
 187
 188         /*
 189          * If this was the last file, make the previous block
 190          * "last block of the last file" even if there is no
 191          * real file there, saves us 1 gap.
 192          */
 193         if (info->si_lf_eblk == bi->i_eblock) {
 194                 info->si_lf_eblk = bi->i_sblock - 1;
 195                 mark_buffer_dirty(info->si_sbh);
 196         }
 197         unlock_kernel();
 198         clear_inode(inode);
 199 }
 200
 201 static void bfs_put_super(struct super_block *s)
 202 {
 203         struct bfs_sb_info *info = BFS_SB(s);
 204         brelse(info->si_sbh);
 205         kfree(info->si_imap);
 206         kfree(info);
 207         s->s_fs_info = NULL;
 208 }
 209
 210 static int bfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 211 {
 212         struct super_block *s = dentry->d_sb;
 213         struct bfs_sb_info *info = BFS_SB(s);
 214         u64 id = huge_encode_dev(s->s_bdev->bd_dev);
 215         buf->f_type = BFS_MAGIC;
 216         buf->f_bsize = s->s_blocksize;
 217         buf->f_blocks = info->si_blocks;
 218         buf->f_bfree = buf->f_bavail = info->si_freeb;
 219         buf->f_files = info->si_lasti + 1 - BFS_ROOT_INO;
 220         buf->f_ffree = info->si_freei;
 221         buf->f_fsid.val[0] = (u32)id;
 222         buf->f_fsid.val[1] = (u32)(id >> 32);
 223         buf->f_namelen = BFS_NAMELEN;
 224         return 0;
 225 }
 226
 227 static void bfs_write_super(struct super_block *s)
 228 {
 229         lock_kernel();
 230         if (!(s->s_flags & MS_RDONLY))
 231                 mark_buffer_dirty(BFS_SB(s)->si_sbh);
 232         s->s_dirt = 0;
 233         unlock_kernel();
 234 }
 235
 236 static struct kmem_cache *bfs_inode_cachep;
 237
 238 static struct inode *bfs_alloc_inode(struct super_block *sb)
 239 {
 240         struct bfs_inode_info *bi;
 241         bi = kmem_cache_alloc(bfs_inode_cachep, GFP_KERNEL);
 242         if (!bi)
 243                 return NULL;
 244         return &bi->vfs_inode;
 245 }
 246
 247 static void bfs_destroy_inode(struct inode *inode)
 248 {
 249         kmem_cache_free(bfs_inode_cachep, BFS_I(inode));
 250 }
 251
 252 static void init_once(struct kmem_cache *cachep, void *foo)
 253 {
 254         struct bfs_inode_info *bi = foo;
 255
 256         inode_init_once(&bi->vfs_inode);
 257 }
 258
 259 static int init_inodecache(void)
 260 {
 261         bfs_inode_cachep = kmem_cache_create("bfs_inode_cache",
 262                                              sizeof(struct bfs_inode_info),
 263                                              0, (SLAB_RECLAIM_ACCOUNT|
 264                                                 SLAB_MEM_SPREAD),
 265                                              init_once);
 266         if (bfs_inode_cachep == NULL)
 267                 return -ENOMEM;
 268         return 0;
 269 }
 270
 271 static void destroy_inodecache(void)
 272 {
 273         kmem_cache_destroy(bfs_inode_cachep);
 274 }
 275
 276 static const struct super_operations bfs_sops = {
 277         .alloc_inode    = bfs_alloc_inode,
 278         .destroy_inode  = bfs_destroy_inode,
 279         .read_inode     = bfs_read_inode,
 280         .write_inode    = bfs_write_inode,
 281         .delete_inode   = bfs_delete_inode,
 282         .put_super      = bfs_put_super,
 283         .write_super    = bfs_write_super,
 284         .statfs         = bfs_statfs,
 285 };
 286
 287 void dump_imap(const char *prefix, struct super_block *s)
 288 {
 289 #ifdef DEBUG
 290         int i;
 291         char *tmpbuf = (char *)get_zeroed_page(GFP_KERNEL);
 292
 293         if (!tmpbuf)
 294                 return;
 295         for (i = BFS_SB(s)->si_lasti; i >= 0; i--) {
 296                 if (i > PAGE_SIZE - 100) break;
 297                 if (test_bit(i, BFS_SB(s)->si_imap))
 298                         strcat(tmpbuf, "1");
 299                 else
 300                         strcat(tmpbuf, "0");
 301         }
 302         printf("BFS-fs: %s: lasti=%08lx <%s>\n",
 303                                 prefix, BFS_SB(s)->si_lasti, tmpbuf);
 304         free_page((unsigned long)tmpbuf);
 305 #endif
 306 }
 307
 308 static int bfs_fill_super(struct super_block *s, void *data, int silent)
 309 {
 310         struct buffer_head *bh;
 311         struct bfs_super_block *bfs_sb;
 312         struct inode *inode;
 313         unsigned i, imap_len;
 314         struct bfs_sb_info *info;
 315
 316         info = kzalloc(sizeof(*info), GFP_KERNEL);
 317         if (!info)
 318                 return -ENOMEM;
 319         s->s_fs_info = info;
 320
 321         sb_set_blocksize(s, BFS_BSIZE);
 322
 323         bh = sb_bread(s, 0);
 324         if(!bh)
 325                 goto out;
 326         bfs_sb = (struct bfs_super_block *)bh->b_data;
 327         if (le32_to_cpu(bfs_sb->s_magic) != BFS_MAGIC) {
 328                 if (!silent)
 329                         printf("No BFS filesystem on %s (magic=%08x)\n",
 330                                 s->s_id,  le32_to_cpu(bfs_sb->s_magic));
 331                 goto out;
 332         }
 333         if (BFS_UNCLEAN(bfs_sb, s) && !silent)
 334                 printf("%s is unclean, continuing\n", s->s_id);
 335
 336         s->s_magic = BFS_MAGIC;
 337         info->si_sbh = bh;
 338         info->si_lasti = (le32_to_cpu(bfs_sb->s_start) - BFS_BSIZE) /
 339                                         sizeof(struct bfs_inode)
 340                                         + BFS_ROOT_INO - 1;
 341         imap_len = (info->si_lasti / 8) + 1;
 342         info->si_imap = kzalloc(imap_len, GFP_KERNEL);
 343         if (!info->si_imap)
 344                 goto out;
 345         for (i = 0; i < BFS_ROOT_INO; i++)
 346                 set_bit(i, info->si_imap);
 347
 348         s->s_op = &bfs_sops;
 349         inode = iget(s, BFS_ROOT_INO);
 350         if (!inode) {
 351                 kfree(info->si_imap);
 352                 goto out;
 353         }
 354         s->s_root = d_alloc_root(inode);
 355         if (!s->s_root) {
 356                 iput(inode);
 357                 kfree(info->si_imap);
 358                 goto out;
 359         }
 360
 361         info->si_blocks = (le32_to_cpu(bfs_sb->s_end) + 1) >> BFS_BSIZE_BITS;
 362         info->si_freeb = (le32_to_cpu(bfs_sb->s_end) + 1
 363                         - le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
 364         info->si_freei = 0;
 365         info->si_lf_eblk = 0;
 366         bh = NULL;
 367         for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
 368                 struct bfs_inode *di;
 369                 int block = (i - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
 370                 int off = (i - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
 371                 unsigned long sblock, eblock;
 372
 373                 if (!off) {
 374                         brelse(bh);
 375                         bh = sb_bread(s, block);
 376                 }
 377
 378                 if (!bh)
 379                         continue;
 380
 381                 di = (struct bfs_inode *)bh->b_data + off;
 382
 383                 if (!di->i_ino) {
 384                         info->si_freei++;
 385                         continue;
 386                 }
 387                 set_bit(i, info->si_imap);
 388                 info->si_freeb -= BFS_FILEBLOCKS(di);
 389
 390                 sblock =  le32_to_cpu(di->i_sblock);
 391                 eblock =  le32_to_cpu(di->i_eblock);
 392                 if (eblock > info->si_lf_eblk)
 393                         info->si_lf_eblk = eblock;
 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)