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