fs/minix/inode.c

/* */
This source file includes following definitions.
minix_put_inode
minix_put_super
minix_read_super
_minix_bmap
minix_bmap
minix_create_block
minix_read_inode
minix_write_inode
   1 /*
   2  *  linux/fs/minix/inode.c
   3  *
   4  *  (C) 1991  Linus Torvalds
   5  */
   6 
   7 #include <linux/string.h>
   8 #include <sys/stat.h>
   9 
  10 #include <linux/sched.h>
  11 #include <linux/minix_fs.h>
  12 #include <linux/kernel.h>
  13 #include <linux/mm.h>
  14 #include <asm/system.h>
  15 
  16 int sync_dev(int dev);
  17 
  18 void minix_put_inode(struct inode *inode)
     /*  */
  19 {
  20         inode->i_size = 0;
  21         minix_truncate(inode);
  22         minix_free_inode(inode);
  23 }
  24 
  25 void minix_put_super(struct super_block *sb)
     /*  */
  26 {
  27         int i;
  28 
  29         lock_super(sb);
  30         sb->s_dev = 0;
  31         for(i = 0 ; i < MINIX_I_MAP_SLOTS ; i++)
  32                 brelse(sb->s_imap[i]);
  33         for(i = 0 ; i < MINIX_Z_MAP_SLOTS ; i++)
  34                 brelse(sb->s_zmap[i]);
  35         free_super(sb);
  36         return;
  37 }
  38 
  39 static struct super_operations minix_sops = { 
  40         minix_read_inode,
  41         minix_write_inode,
  42         minix_put_inode,
  43         minix_put_super
  44 };
  45 
  46 struct super_block *minix_read_super(struct super_block *s,void *data)
     /*  */
  47 {
  48         struct buffer_head *bh;
  49         int i,dev=s->s_dev,block;
  50 
  51         lock_super(s);
  52         if (!(bh = bread(dev,1))) {
  53                 s->s_dev=0;
  54                 free_super(s);
  55                 printk("bread failed\n");
  56                 return NULL;
  57         }
  58         *((struct minix_super_block *) s) =
  59                 *((struct minix_super_block *) bh->b_data);
  60         brelse(bh);
  61         if (s->s_magic != MINIX_SUPER_MAGIC) {
  62                 s->s_dev = 0;
  63                 free_super(s);
  64                 printk("magic match failed\n");
  65                 return NULL;
  66         }
  67         for (i=0;i < MINIX_I_MAP_SLOTS;i++)
  68                 s->s_imap[i] = NULL;
  69         for (i=0;i < MINIX_Z_MAP_SLOTS;i++)
  70                 s->s_zmap[i] = NULL;
  71         block=2;
  72         for (i=0 ; i < s->s_imap_blocks ; i++)
  73                 if (s->s_imap[i]=bread(dev,block))
  74                         block++;
  75                 else
  76                         break;
  77         for (i=0 ; i < s->s_zmap_blocks ; i++)
  78                 if (s->s_zmap[i]=bread(dev,block))
  79                         block++;
  80                 else
  81                         break;
  82         if (block != 2+s->s_imap_blocks+s->s_zmap_blocks) {
  83                 for(i=0;i<MINIX_I_MAP_SLOTS;i++)
  84                         brelse(s->s_imap[i]);
  85                 for(i=0;i<MINIX_Z_MAP_SLOTS;i++)
  86                         brelse(s->s_zmap[i]);
  87                 s->s_dev=0;
  88                 free_super(s);
  89                 printk("block failed\n");
  90                 return NULL;
  91         }
  92         s->s_imap[0]->b_data[0] |= 1;
  93         s->s_zmap[0]->b_data[0] |= 1;
  94         free_super(s);
  95         /* set up enough so that it can read an inode */
  96         s->s_dev = dev;
  97         s->s_op = &minix_sops;
  98         if (!(s->s_mounted = iget(dev,MINIX_ROOT_INO))) {
  99                 s->s_dev=0;
 100                 printk("get root inode failed\n");
 101                 return NULL;
 102         }
 103         return s;
 104 }
 105 
 106 static int _minix_bmap(struct inode * inode,int block,int create)
     /*  */
 107 {
 108         struct buffer_head * bh;
 109         int i;
 110 
 111         if (block<0) {
 112                 printk("_minix_bmap: block<0");
 113                 return 0;
 114         }
 115         if (block >= 7+512+512*512) {
 116                 printk("_minix_bmap: block>big");
 117                 return 0;
 118         }
 119         if (block<7) {
 120                 if (create && !inode->i_data[block])
 121                         if (inode->i_data[block]=minix_new_block(inode->i_dev)) {
 122                                 inode->i_ctime=CURRENT_TIME;
 123                                 inode->i_dirt=1;
 124                         }
 125                 return inode->i_data[block];
 126         }
 127         block -= 7;
 128         if (block<512) {
 129                 if (create && !inode->i_data[7])
 130                         if (inode->i_data[7]=minix_new_block(inode->i_dev)) {
 131                                 inode->i_dirt=1;
 132                                 inode->i_ctime=CURRENT_TIME;
 133                         }
 134                 if (!inode->i_data[7])
 135                         return 0;
 136                 if (!(bh = bread(inode->i_dev,inode->i_data[7])))
 137                         return 0;
 138                 i = ((unsigned short *) (bh->b_data))[block];
 139                 if (create && !i)
 140                         if (i=minix_new_block(inode->i_dev)) {
 141                                 ((unsigned short *) (bh->b_data))[block]=i;
 142                                 bh->b_dirt=1;
 143                         }
 144                 brelse(bh);
 145                 return i;
 146         }
 147         block -= 512;
 148         if (create && !inode->i_data[8])
 149                 if (inode->i_data[8]=minix_new_block(inode->i_dev)) {
 150                         inode->i_dirt=1;
 151                         inode->i_ctime=CURRENT_TIME;
 152                 }
 153         if (!inode->i_data[8])
 154                 return 0;
 155         if (!(bh=bread(inode->i_dev,inode->i_data[8])))
 156                 return 0;
 157         i = ((unsigned short *)bh->b_data)[block>>9];
 158         if (create && !i)
 159                 if (i=minix_new_block(inode->i_dev)) {
 160                         ((unsigned short *) (bh->b_data))[block>>9]=i;
 161                         bh->b_dirt=1;
 162                 }
 163         brelse(bh);
 164         if (!i)
 165                 return 0;
 166         if (!(bh=bread(inode->i_dev,i)))
 167                 return 0;
 168         i = ((unsigned short *)bh->b_data)[block&511];
 169         if (create && !i)
 170                 if (i=minix_new_block(inode->i_dev)) {
 171                         ((unsigned short *) (bh->b_data))[block&511]=i;
 172                         bh->b_dirt=1;
 173                 }
 174         brelse(bh);
 175         return i;
 176 }
 177 
 178 int minix_bmap(struct inode * inode,int block)
     /*  */
 179 {
 180         return _minix_bmap(inode,block,0);
 181 }
 182 
 183 int minix_create_block(struct inode * inode, int block)
     /*  */
 184 {
 185         return _minix_bmap(inode,block,1);
 186 }
 187 
 188 void minix_read_inode(struct inode * inode)
     /*  */
 189 {
 190         struct buffer_head * bh;
 191         struct minix_inode * raw_inode;
 192         int block;
 193 
 194         block = 2 + inode->i_sb->s_imap_blocks + inode->i_sb->s_zmap_blocks +
 195                 (inode->i_ino-1)/MINIX_INODES_PER_BLOCK;
 196         if (!(bh=bread(inode->i_dev,block)))
 197                 panic("unable to read i-node block");
 198         raw_inode = ((struct minix_inode *) bh->b_data) +
 199                 (inode->i_ino-1)%MINIX_INODES_PER_BLOCK;
 200         inode->i_mode = raw_inode->i_mode;
 201         inode->i_uid = raw_inode->i_uid;
 202         inode->i_gid = raw_inode->i_gid;
 203         inode->i_nlink = raw_inode->i_nlinks;
 204         inode->i_size = raw_inode->i_size;
 205         inode->i_mtime = inode->i_atime = inode->i_ctime = raw_inode->i_time;
 206         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 207                 inode->i_rdev = raw_inode->i_zone[0];
 208         else for (block = 0; block < 9; block++)
 209                 inode->i_data[block] = raw_inode->i_zone[block];
 210         brelse(bh);
 211         inode->i_op = NULL;
 212         if (S_ISREG(inode->i_mode))
 213                 inode->i_op = &minix_file_inode_operations;
 214         else if (S_ISDIR(inode->i_mode))
 215                 inode->i_op = &minix_dir_inode_operations;
 216         else if (S_ISLNK(inode->i_mode))
 217                 inode->i_op = &minix_symlink_inode_operations;
 218         else if (S_ISCHR(inode->i_mode))
 219                 inode->i_op = &minix_chrdev_inode_operations;
 220         else if (S_ISBLK(inode->i_mode))
 221                 inode->i_op = &minix_blkdev_inode_operations;
 222 }
 223 
 224 void minix_write_inode(struct inode * inode)
     /*  */
 225 {
 226         struct buffer_head * bh;
 227         struct minix_inode * raw_inode;
 228         int block;
 229 
 230         block = 2 + inode->i_sb->s_imap_blocks + inode->i_sb->s_zmap_blocks +
 231                 (inode->i_ino-1)/MINIX_INODES_PER_BLOCK;
 232         if (!(bh=bread(inode->i_dev,block)))
 233                 panic("unable to read i-node block");
 234         raw_inode = ((struct minix_inode *)bh->b_data) +
 235                 (inode->i_ino-1)%MINIX_INODES_PER_BLOCK;
 236         raw_inode->i_mode = inode->i_mode;
 237         raw_inode->i_uid = inode->i_uid;
 238         raw_inode->i_gid = inode->i_gid;
 239         raw_inode->i_nlinks = inode->i_nlink;
 240         raw_inode->i_size = inode->i_size;
 241         raw_inode->i_time = inode->i_mtime;
 242         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 243                 raw_inode->i_zone[0] = inode->i_rdev;
 244         else for (block = 0; block < 9; block++)
 245                 raw_inode->i_zone[block] = inode->i_data[block];
 246         bh->b_dirt=1;
 247         inode->i_dirt=0;
 248         brelse(bh);
 249 }
/* */
root/fs/minix/inode.c

DEFINITIONS
