fs/minix/inode.c

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

DEFINITIONS
