fs/ext/inode.c

/* */
This source file includes following definitions.
wait_on_buffer
ext_put_inode
ext_put_super
ext_read_super
ext_write_super
ext_statfs
block_bmap
ext_bmap
inode_getblk
block_getblk
ext_getblk
ext_bread
ext_read_inode
ext_write_inode
   1 /*
   2  *  linux/fs/ext/inode.c
   3  *
   4  *  Copyright (C) 1992  Remy Card (card@masi.ibp.fr)
   5  *
   6  *  from
   7  *
   8  *  linux/fs/minix/inode.c
   9  *
  10  *  Copyright (C) 1991, 1992  Linus Torvalds
  11  */
  12 
  13 #include <linux/sched.h>
  14 #include <linux/ext_fs.h>
  15 #include <linux/kernel.h>
  16 #include <linux/mm.h>
  17 #include <linux/string.h>
  18 #include <linux/stat.h>
  19 
  20 #include <asm/system.h>
  21 #include <asm/segment.h>
  22 
  23 int sync_dev(int dev);
  24 
  25 static inline void wait_on_buffer(struct buffer_head * bh)
     /*  */
  26 {
  27         cli();
  28         while (bh->b_lock)
  29                 sleep_on(&bh->b_wait);
  30         sti();
  31 }
  32 
  33 void ext_put_inode(struct inode *inode)
     /*  */
  34 {
  35         inode->i_size = 0;
  36         ext_truncate(inode);
  37         ext_free_inode(inode);
  38 }
  39 
  40 void ext_put_super(struct super_block *sb)
     /*  */
  41 {
  42 
  43         lock_super(sb);
  44         sb->s_dev = 0;
  45         if (sb->u.ext_sb.s_firstfreeinodeblock)
  46                 brelse (sb->u.ext_sb.s_firstfreeinodeblock);
  47         if (sb->u.ext_sb.s_firstfreeblock)
  48                 brelse (sb->u.ext_sb.s_firstfreeblock);
  49         free_super(sb);
  50         return;
  51 }
  52 
  53 static struct super_operations ext_sops = { 
  54         ext_read_inode,
  55         ext_write_inode,
  56         ext_put_inode,
  57         ext_put_super,
  58         ext_write_super,
  59         ext_statfs
  60 };
  61 
  62 struct super_block *ext_read_super(struct super_block *s,void *data)
     /*  */
  63 {
  64         struct buffer_head *bh;
  65         struct ext_super_block *es;
  66         int dev = s->s_dev,block;
  67 
  68         lock_super(s);
  69         if (!(bh = bread(dev, 1, BLOCK_SIZE))) {
  70                 s->s_dev=0;
  71                 free_super(s);
  72                 printk("bread failed\n");
  73                 return NULL;
  74         }
  75         es = (struct ext_super_block *) bh->b_data;
  76         s->s_blocksize = 1024;
  77         s->u.ext_sb.s_ninodes = es->s_ninodes;
  78         s->u.ext_sb.s_nzones = es->s_nzones;
  79         s->u.ext_sb.s_firstdatazone = es->s_firstdatazone;
  80         s->u.ext_sb.s_log_zone_size = es->s_log_zone_size;
  81         s->u.ext_sb.s_max_size = es->s_max_size;
  82         s->s_magic = es->s_magic;
  83         s->u.ext_sb.s_firstfreeblocknumber = es->s_firstfreeblock;
  84         s->u.ext_sb.s_freeblockscount = es->s_freeblockscount;
  85         s->u.ext_sb.s_firstfreeinodenumber = es->s_firstfreeinode;
  86         s->u.ext_sb.s_freeinodescount = es->s_freeinodescount;
  87         brelse(bh);
  88         if (s->s_magic != EXT_SUPER_MAGIC) {
  89                 s->s_dev = 0;
  90                 free_super(s);
  91                 printk("magic match failed\n");
  92                 return NULL;
  93         }
  94         if (!s->u.ext_sb.s_firstfreeblocknumber)
  95                 s->u.ext_sb.s_firstfreeblock = NULL;
  96         else
  97                 if (!(s->u.ext_sb.s_firstfreeblock = bread(dev,
  98                         s->u.ext_sb.s_firstfreeblocknumber, BLOCK_SIZE))) {
  99                         printk ("ext_read_super: unable to read first free block\n");
 100                         s->s_dev = 0;
 101                         free_super(s);
 102                         return NULL;
 103                 }
 104         if (!s->u.ext_sb.s_firstfreeinodenumber)
 105                 s->u.ext_sb.s_firstfreeinodeblock = NULL;
 106         else {
 107                 block = 2 + (s->u.ext_sb.s_firstfreeinodenumber - 1) / EXT_INODES_PER_BLOCK;
 108                 if (!(s->u.ext_sb.s_firstfreeinodeblock = bread(dev, block, BLOCK_SIZE))) {
 109                         printk ("ext_read_super: unable to read first free inode block\n");
 110                         brelse(s->u.ext_sb.s_firstfreeblock);
 111                         s->s_dev = 0;
 112                         free_super (s);
 113                         return NULL;
 114                 }
 115         }
 116         free_super(s);
 117         /* set up enough so that it can read an inode */
 118         s->s_dev = dev;
 119         s->s_op = &ext_sops;
 120         if (!(s->s_mounted = iget(dev,EXT_ROOT_INO))) {
 121                 s->s_dev=0;
 122                 printk("get root inode failed\n");
 123                 return NULL;
 124         }
 125         return s;
 126 }
 127 
 128 void ext_write_super (struct super_block *sb)
     /*  */
 129 {
 130         struct buffer_head * bh;
 131         struct ext_super_block * es;
 132 
 133         if (!(bh = bread(sb->s_dev, 1, BLOCK_SIZE))) {
 134                 printk ("ext_write_super: bread failed\n");
 135                 return;
 136         }
 137         es = (struct ext_super_block *) bh->b_data;
 138         es->s_firstfreeblock = sb->u.ext_sb.s_firstfreeblocknumber;
 139         es->s_freeblockscount = sb->u.ext_sb.s_freeblockscount;
 140         es->s_firstfreeinode = sb->u.ext_sb.s_firstfreeinodenumber;
 141         es->s_freeinodescount = sb->u.ext_sb.s_freeinodescount;
 142         bh->b_dirt = 1;
 143         brelse (bh);
 144         sb->s_dirt = 0;
 145 }
 146 
 147 void ext_statfs (struct super_block *sb, struct statfs *buf)
     /*  */
 148 {
 149         long tmp;
 150 
 151         put_fs_long(EXT_SUPER_MAGIC, &buf->f_type);
 152         put_fs_long(1024, &buf->f_bsize);
 153         put_fs_long(sb->u.ext_sb.s_nzones << sb->u.ext_sb.s_log_zone_size,
 154                 &buf->f_blocks);
 155         tmp = ext_count_free_blocks(sb);
 156         put_fs_long(tmp, &buf->f_bfree);
 157         put_fs_long(tmp, &buf->f_bavail);
 158         put_fs_long(sb->u.ext_sb.s_ninodes, &buf->f_files);
 159         put_fs_long(ext_count_free_inodes(sb), &buf->f_ffree);
 160         /* Don't know what value to put in buf->f_fsid */
 161 }
 162 
 163 #define inode_bmap(inode,nr) ((inode)->u.ext_i.i_data[(nr)])
 164 
 165 static int block_bmap(struct buffer_head * bh, int nr)
     /*  */
 166 {
 167         int tmp;
 168 
 169         if (!bh)
 170                 return 0;
 171         tmp = ((unsigned long *) bh->b_data)[nr];
 172         brelse(bh);
 173         return tmp;
 174 }
 175 
 176 int ext_bmap(struct inode * inode,int block)
     /*  */
 177 {
 178         int i;
 179 
 180         if (block<0) {
 181                 printk("ext_bmap: block<0");
 182                 return 0;
 183         }
 184         if (block >= 9+256+256*256+256*256*256) {
 185                 printk("ext_bmap: block>big");
 186                 return 0;
 187         }
 188         if (block<9)
 189                 return inode_bmap(inode,block);
 190         block -= 9;
 191         if (block<256) {
 192                 i = inode_bmap(inode,9);
 193                 if (!i)
 194                         return 0;
 195                 return block_bmap(bread(inode->i_dev,i,BLOCK_SIZE),block);
 196         }
 197         block -= 256;
 198         if (block<256*256) {
 199                 i = inode_bmap(inode,10);
 200                 if (!i)
 201                         return 0;
 202                 i = block_bmap(bread(inode->i_dev,i,BLOCK_SIZE),block>>8);
 203                 if (!i)
 204                         return 0;
 205                 return block_bmap(bread(inode->i_dev,i,BLOCK_SIZE),block & 255);
 206         }
 207         block -= 256*256;
 208         i = inode_bmap(inode,11);
 209         if (!i)
 210                 return 0;
 211         i = block_bmap(bread(inode->i_dev,i,BLOCK_SIZE),block>>16);
 212         if (!i)
 213                 return 0;
 214         i = block_bmap(bread(inode->i_dev,i,BLOCK_SIZE),(block>>8) & 255);
 215         if (!i)
 216                 return 0;
 217         return block_bmap(bread(inode->i_dev,i,BLOCK_SIZE),block & 255);
 218 }
 219 
 220 static struct buffer_head * inode_getblk(struct inode * inode, int nr, int create)
     /*  */
 221 {
 222         int tmp;
 223         unsigned long * p;
 224         struct buffer_head * result;
 225 
 226         p = inode->u.ext_i.i_data + nr;
 227 repeat:
 228         tmp = *p;
 229         if (tmp) {
 230                 result = getblk(inode->i_dev, tmp, BLOCK_SIZE);
 231                 if (tmp == *p)
 232                         return result;
 233                 brelse(result);
 234                 goto repeat;
 235         }
 236         if (!create)
 237                 return NULL;
 238         tmp = ext_new_block(inode->i_dev);
 239         if (!tmp)
 240                 return NULL;
 241         result = getblk(inode->i_dev, tmp, BLOCK_SIZE);
 242         if (*p) {
 243                 ext_free_block(inode->i_dev,tmp);
 244                 brelse(result);
 245                 goto repeat;
 246         }
 247         *p = tmp;
 248         inode->i_ctime = CURRENT_TIME;
 249         inode->i_dirt = 1;
 250         return result;
 251 }
 252 
 253 static struct buffer_head * block_getblk(struct buffer_head * bh, int nr, int create)
     /*  */
 254 {
 255         int tmp;
 256         unsigned long * p;
 257         struct buffer_head * result;
 258 
 259         if (!bh)
 260                 return NULL;
 261         if (!bh->b_uptodate) {
 262                 ll_rw_block(READ,bh);
 263                 wait_on_buffer(bh);
 264                 if (!bh->b_uptodate) {
 265                         brelse(bh);
 266                         return NULL;
 267                 }
 268         }
 269         p = nr + (unsigned long *) bh->b_data;
 270 repeat:
 271         tmp = *p;
 272         if (tmp) {
 273                 result = getblk(bh->b_dev, tmp, BLOCK_SIZE);
 274                 if (tmp == *p) {
 275                         brelse(bh);
 276                         return result;
 277                 }
 278                 brelse(result);
 279                 goto repeat;
 280         }
 281         if (!create) {
 282                 brelse(bh);
 283                 return NULL;
 284         }
 285         tmp = ext_new_block(bh->b_dev);
 286         if (!tmp) {
 287                 brelse(bh);
 288                 return NULL;
 289         }
 290         result = getblk(bh->b_dev, tmp, BLOCK_SIZE);
 291         if (*p) {
 292                 ext_free_block(bh->b_dev,tmp);
 293                 brelse(result);
 294                 goto repeat;
 295         }
 296         *p = tmp;
 297         bh->b_dirt = 1;
 298         brelse(bh);
 299         return result;
 300 }
 301 
 302 struct buffer_head * ext_getblk(struct inode * inode, int block, int create)
     /*  */
 303 {
 304         struct buffer_head * bh;
 305 
 306         if (block<0) {
 307                 printk("ext_getblk: block<0\n");
 308                 return NULL;
 309         }
 310         if (block >= 9+256+256*256+256*256*256) {
 311                 printk("ext_getblk: block>big\n");
 312                 return NULL;
 313         }
 314         if (block<9)
 315                 return inode_getblk(inode,block,create);
 316         block -= 9;
 317         if (block<256) {
 318                 bh = inode_getblk(inode,9,create);
 319                 return block_getblk(bh,block,create);
 320         }
 321         block -= 256;
 322         if (block<256*256) {
 323                 bh = inode_getblk(inode,10,create);
 324                 bh = block_getblk(bh,block>>8,create);
 325                 return block_getblk(bh,block & 255,create);
 326         }
 327         block -= 256*256;
 328         bh = inode_getblk(inode,11,create);
 329         bh = block_getblk(bh,block>>16,create);
 330         bh = block_getblk(bh,(block>>8) & 255,create);
 331         return block_getblk(bh,block & 255,create);
 332 }
 333 
 334 struct buffer_head * ext_bread(struct inode * inode, int block, int create)
     /*  */
 335 {
 336         struct buffer_head * bh;
 337 
 338         bh = ext_getblk(inode,block,create);
 339         if (!bh || bh->b_uptodate) 
 340                 return bh;
 341         ll_rw_block(READ,bh);
 342         wait_on_buffer(bh);
 343         if (bh->b_uptodate)
 344                 return bh;
 345         brelse(bh);
 346         return NULL;
 347 }
 348 
 349 void ext_read_inode(struct inode * inode)
     /*  */
 350 {
 351         struct buffer_head * bh;
 352         struct ext_inode * raw_inode;
 353         int block;
 354 
 355         block = 2 + (inode->i_ino-1)/EXT_INODES_PER_BLOCK;
 356         if (!(bh=bread(inode->i_dev, block, BLOCK_SIZE)))
 357                 panic("unable to read i-node block");
 358         raw_inode = ((struct ext_inode *) bh->b_data) +
 359                 (inode->i_ino-1)%EXT_INODES_PER_BLOCK;
 360         inode->i_mode = raw_inode->i_mode;
 361         inode->i_uid = raw_inode->i_uid;
 362         inode->i_gid = raw_inode->i_gid;
 363         inode->i_nlink = raw_inode->i_nlinks;
 364         inode->i_size = raw_inode->i_size;
 365         inode->i_mtime = inode->i_atime = inode->i_ctime = raw_inode->i_time;
 366         inode->i_blocks = inode->i_blksize = 0;
 367         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 368                 inode->i_rdev = raw_inode->i_zone[0];
 369         else for (block = 0; block < 12; block++)
 370                 inode->u.ext_i.i_data[block] = raw_inode->i_zone[block];
 371         brelse(bh);
 372         inode->i_op = NULL;
 373         if (S_ISREG(inode->i_mode))
 374                 inode->i_op = &ext_file_inode_operations;
 375         else if (S_ISDIR(inode->i_mode))
 376                 inode->i_op = &ext_dir_inode_operations;
 377         else if (S_ISLNK(inode->i_mode))
 378                 inode->i_op = &ext_symlink_inode_operations;
 379         else if (S_ISCHR(inode->i_mode))
 380                 inode->i_op = &ext_chrdev_inode_operations;
 381         else if (S_ISBLK(inode->i_mode))
 382                 inode->i_op = &ext_blkdev_inode_operations;
 383         else if (S_ISFIFO(inode->i_mode)) {
 384                 inode->i_op = &ext_fifo_inode_operations;
 385                 inode->i_pipe = 1;
 386                 PIPE_BASE(*inode) = NULL;
 387                 PIPE_HEAD(*inode) = PIPE_TAIL(*inode) = 0;
 388                 PIPE_READ_WAIT(*inode) = PIPE_WRITE_WAIT(*inode) = NULL;
 389                 PIPE_READERS(*inode) = PIPE_WRITERS(*inode) = 0;
 390         }
 391 }
 392 
 393 void ext_write_inode(struct inode * inode)
     /*  */
 394 {
 395         struct buffer_head * bh;
 396         struct ext_inode * raw_inode;
 397         int block;
 398 
 399         block = 2 + (inode->i_ino-1)/EXT_INODES_PER_BLOCK;
 400         if (!(bh=bread(inode->i_dev, block, BLOCK_SIZE)))
 401                 panic("unable to read i-node block");
 402         raw_inode = ((struct ext_inode *)bh->b_data) +
 403                 (inode->i_ino-1)%EXT_INODES_PER_BLOCK;
 404         raw_inode->i_mode = inode->i_mode;
 405         raw_inode->i_uid = inode->i_uid;
 406         raw_inode->i_gid = inode->i_gid;
 407         raw_inode->i_nlinks = inode->i_nlink;
 408         raw_inode->i_size = inode->i_size;
 409         raw_inode->i_time = inode->i_mtime;
 410         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 411                 raw_inode->i_zone[0] = inode->i_rdev;
 412         else for (block = 0; block < 12; block++)
 413                 raw_inode->i_zone[block] = inode->u.ext_i.i_data[block];
 414         bh->b_dirt=1;
 415         inode->i_dirt=0;
 416         brelse(bh);
 417 }
/* */
root/fs/ext/inode.c

DEFINITIONS
