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/locks.h>
  13 #include <linux/bfs_fs.h>
  14 #include <linux/smp_lock.h>
  15
  16 #include <asm/uaccess.h>
  17
  18 #include "bfs_defs.h"
  19
  20 MODULE_AUTHOR("Tigran A. Aivazian <tigran@veritas.com>");
  21 MODULE_DESCRIPTION("SCO UnixWare BFS filesystem for Linux");
  22 MODULE_LICENSE("GPL");
  23 EXPORT_NO_SYMBOLS;
  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         kdev_t dev = inode->i_dev;
  39         struct bfs_inode * di;
  40         struct buffer_head * bh;
  41         int block, off;
  42
  43         if (ino < BFS_ROOT_INO || ino > inode->i_sb->su_lasti) {
  44                 printf("Bad inode number %s:%08lx\n", bdevname(dev), ino);
  45                 make_bad_inode(inode);
  46                 return;
  47         }
  48
  49         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
  50         bh = sb_bread(inode->i_sb, block);
  51         if (!bh) {
  52                 printf("Unable to read inode %s:%08lx\n", bdevname(dev), 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 & di->i_mode;
  61         if (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 (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         inode->i_uid = di->i_uid;
  73         inode->i_gid = di->i_gid;
  74         inode->i_nlink = di->i_nlink;
  75         inode->i_size = BFS_FILESIZE(di);
  76         inode->i_blocks = BFS_FILEBLOCKS(di);
  77         inode->i_blksize = PAGE_SIZE;
  78         inode->i_atime = di->i_atime;
  79         inode->i_mtime = di->i_mtime;
  80         inode->i_ctime = di->i_ctime;
  81         inode->iu_dsk_ino = di->i_ino; /* can be 0 so we store a copy */
  82         inode->iu_sblock = di->i_sblock;
  83         inode->iu_eblock = di->i_eblock;
  84
  85         brelse(bh);
  86 }
  87
  88 static void bfs_write_inode(struct inode * inode, int unused)
  89 {
  90         unsigned long ino = inode->i_ino;
  91         kdev_t dev = inode->i_dev;
  92         struct bfs_inode * di;
  93         struct buffer_head * bh;
  94         int block, off;
  95
  96         if (ino < BFS_ROOT_INO || ino > inode->i_sb->su_lasti) {
  97                 printf("Bad inode number %s:%08lx\n", bdevname(dev), ino);
  98                 return;
  99         }
 100
 101         lock_kernel();
 102         block = (ino - BFS_ROOT_INO)/BFS_INODES_PER_BLOCK + 1;
 103         bh = sb_bread(inode->i_sb, block);
 104         if (!bh) {
 105                 printf("Unable to read inode %s:%08lx\n", bdevname(dev), ino);
 106                 unlock_kernel();
 107                 return;
 108         }
 109
 110         off = (ino - BFS_ROOT_INO)%BFS_INODES_PER_BLOCK;
 111         di = (struct bfs_inode *)bh->b_data + off;
 112
 113         if (inode->i_ino == BFS_ROOT_INO)
 114                 di->i_vtype = BFS_VDIR;
 115         else
 116                 di->i_vtype = BFS_VREG;
 117
 118         di->i_ino = inode->i_ino;
 119         di->i_mode = inode->i_mode;
 120         di->i_uid = inode->i_uid;
 121         di->i_gid = inode->i_gid;
 122         di->i_nlink = inode->i_nlink;
 123         di->i_atime = inode->i_atime;
 124         di->i_mtime = inode->i_mtime;
 125         di->i_ctime = inode->i_ctime;
 126         di->i_sblock = inode->iu_sblock;
 127         di->i_eblock = inode->iu_eblock;
 128         di->i_eoffset = di->i_sblock * BFS_BSIZE + inode->i_size - 1;
 129
 130         mark_buffer_dirty(bh);
 131         brelse(bh);
 132         unlock_kernel();
 133 }
 134
 135 static void bfs_delete_inode(struct inode * inode)
 136 {
 137         unsigned long ino = inode->i_ino;
 138         kdev_t dev = inode->i_dev;
 139         struct bfs_inode * di;
 140         struct buffer_head * bh;
 141         int block, off;
 142         struct super_block * s = inode->i_sb;
 143
 144         dprintf("ino=%08lx\n", inode->i_ino);
 145
 146         if (inode->i_ino < BFS_ROOT_INO || inode->i_ino > inode->i_sb->su_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;
 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", bdevname(dev), 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                 s->su_freeb += BFS_FILEBLOCKS(di);
 166                 s->su_freei++;
 167                 clear_bit(di->i_ino, s->su_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 (s->su_lf_eblk == inode->iu_eblock) {
 179                 s->su_lf_eblk = inode->iu_sblock - 1;
 180                 mark_buffer_dirty(s->su_sbh);
 181         }
 182         unlock_kernel();
 183         clear_inode(inode);
 184 }
 185
 186 static void bfs_put_super(struct super_block *s)
 187 {
 188         brelse(s->su_sbh);
 189         kfree(s->su_imap);
 190 }
 191
 192 static int bfs_statfs(struct super_block *s, struct statfs *buf)
 193 {
 194         buf->f_type = BFS_MAGIC;
 195         buf->f_bsize = s->s_blocksize;
 196         buf->f_blocks = s->su_blocks;
 197         buf->f_bfree = buf->f_bavail = s->su_freeb;
 198         buf->f_files = s->su_lasti + 1 - BFS_ROOT_INO;
 199         buf->f_ffree = s->su_freei;
 200         buf->f_fsid.val[0] = kdev_t_to_nr(s->s_dev);
 201         buf->f_namelen = BFS_NAMELEN;
 202         return 0;
 203 }
 204
 205 static void bfs_write_super(struct super_block *s)
 206 {
 207         if (!(s->s_flags & MS_RDONLY))
 208                 mark_buffer_dirty(s->su_sbh);
 209         s->s_dirt = 0;
 210 }
 211
 212 static struct super_operations bfs_sops = {
 213         read_inode:     bfs_read_inode,
 214         write_inode:    bfs_write_inode,
 215         delete_inode:   bfs_delete_inode,
 216         put_super:      bfs_put_super,
 217         write_super:    bfs_write_super,
 218         statfs:         bfs_statfs,
 219 };
 220
 221 void dump_imap(const char *prefix, struct super_block * s)
 222 {
 223 #if 0
 224         int i;
 225         char *tmpbuf = (char *)get_free_page(GFP_KERNEL);
 226
 227         if (!tmpbuf)
 228                 return;
 229         for (i=s->su_lasti; i>=0; i--) {
 230                 if (i>PAGE_SIZE-100) break;
 231                 if (test_bit(i, s->su_imap))
 232                         strcat(tmpbuf, "1");
 233                 else
 234                         strcat(tmpbuf, "0");
 235         }
 236         printk(KERN_ERR "BFS-fs: %s: lasti=%08lx <%s>\n", prefix, s->su_lasti, tmpbuf);
 237         free_page((unsigned long)tmpbuf);
 238 #endif
 239 }
 240
 241 static struct super_block * bfs_read_super(struct super_block * s,
 242         void * data, int silent)
 243 {
 244         kdev_t dev;
 245         struct buffer_head * bh;
 246         struct bfs_super_block * bfs_sb;
 247         struct inode * inode;
 248         int i, imap_len;
 249
 250         dev = s->s_dev;
 251         set_blocksize(dev, BFS_BSIZE);
 252         s->s_blocksize = BFS_BSIZE;
 253         s->s_blocksize_bits = BFS_BSIZE_BITS;
 254
 255         bh = sb_bread(s, 0);
 256         if(!bh)
 257                 goto out;
 258         bfs_sb = (struct bfs_super_block *)bh->b_data;
 259         if (bfs_sb->s_magic != BFS_MAGIC) {
 260                 if (!silent)
 261                         printf("No BFS filesystem on %s (magic=%08x)\n",
 262                                 bdevname(dev), bfs_sb->s_magic);
 263                 goto out;
 264         }
 265         if (BFS_UNCLEAN(bfs_sb, s) && !silent)
 266                 printf("%s is unclean, continuing\n", bdevname(dev));
 267
 268         s->s_magic = BFS_MAGIC;
 269         s->su_bfs_sb = bfs_sb;
 270         s->su_sbh = bh;
 271         s->su_lasti = (bfs_sb->s_start - BFS_BSIZE)/sizeof(struct bfs_inode)
 272                         + BFS_ROOT_INO - 1;
 273
 274         imap_len = s->su_lasti/8 + 1;
 275         s->su_imap = kmalloc(imap_len, GFP_KERNEL);
 276         if (!s->su_imap)
 277                 goto out;
 278         memset(s->su_imap, 0, imap_len);
 279         for (i=0; i<BFS_ROOT_INO; i++)
 280                 set_bit(i, s->su_imap);
 281
 282         s->s_op = &bfs_sops;
 283         inode = iget(s, BFS_ROOT_INO);
 284         if (!inode) {
 285                 kfree(s->su_imap);
 286                 goto out;
 287         }
 288         s->s_root = d_alloc_root(inode);
 289         if (!s->s_root) {
 290                 iput(inode);
 291                 kfree(s->su_imap);
 292                 goto out;
 293         }
 294
 295         s->su_blocks = (bfs_sb->s_end + 1)>>BFS_BSIZE_BITS; /* for statfs(2) */
 296         s->su_freeb = (bfs_sb->s_end + 1 - bfs_sb->s_start)>>BFS_BSIZE_BITS;
 297         s->su_freei = 0;
 298         s->su_lf_eblk = 0;
 299         s->su_lf_sblk = 0;
 300         s->su_lf_ioff = 0;
 301         for (i=BFS_ROOT_INO; i<=s->su_lasti; i++) {
 302                 inode = iget(s,i);
 303                 if (inode->iu_dsk_ino == 0)
 304                         s->su_freei++;
 305                 else {
 306                         set_bit(i, s->su_imap);
 307                         s->su_freeb -= inode->i_blocks;
 308                         if (inode->iu_eblock > s->su_lf_eblk) {
 309                                 s->su_lf_eblk = inode->iu_eblock;
 310                                 s->su_lf_sblk = inode->iu_sblock;
 311                                 s->su_lf_ioff = BFS_INO2OFF(i);
 312                         }
 313                 }
 314                 iput(inode);
 315         }
 316         if (!(s->s_flags & MS_RDONLY)) {
 317                 mark_buffer_dirty(bh);
 318                 s->s_dirt = 1;
 319         }
 320         dump_imap("read_super", s);
 321         return s;
 322
 323 out:
 324         brelse(bh);
 325         return NULL;
 326 }
 327
 328 static DECLARE_FSTYPE_DEV(bfs_fs_type, "bfs", bfs_read_super);
 329
 330 static int __init init_bfs_fs(void)
 331 {
 332         return register_filesystem(&bfs_fs_type);
 333 }
 334
 335 static void __exit exit_bfs_fs(void)
 336 {
 337         unregister_filesystem(&bfs_fs_type);
 338 }
 339
 340 module_init(init_bfs_fs)
 341 module_exit(exit_bfs_fs)