1/* 2 * linux/fs/minix/inode.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * Copyright (C) 1996 Gertjan van Wingerde (gertjan@cs.vu.nl) 7 * Minix V2 fs support. 8 * 9 * Modified for 680x0 by Andreas Schwab 10 */ 11 12#include <linux/module.h> 13 14#include <linux/fs.h> 15#include <linux/minix_fs.h> 16#include <linux/slab.h> 17#include <linux/locks.h> 18#include <linux/init.h> 19#include <linux/smp_lock.h> 20#include <linux/highuid.h> 21#include <linux/blkdev.h> 22 23static void minix_read_inode(struct inode * inode); 24static void minix_write_inode(struct inode * inode, int wait); 25static int minix_statfs(struct super_block *sb, struct statfs *buf); 26static int minix_remount (struct super_block * sb, int * flags, char * data); 27 28static void minix_delete_inode(struct inode *inode) 29{ 30 lock_kernel(); 31 32 inode->i_size = 0; 33 minix_truncate(inode); 34 minix_free_inode(inode); 35 36 unlock_kernel(); 37} 38 39static void minix_commit_super(struct super_block * sb) 40{ 41 mark_buffer_dirty(sb->u.minix_sb.s_sbh); 42 sb->s_dirt = 0; 43} 44 45static void minix_write_super(struct super_block * sb) 46{ 47 struct minix_super_block * ms; 48 49 if (!(sb->s_flags & MS_RDONLY)) { 50 ms = sb->u.minix_sb.s_ms; 51 52 if (ms->s_state & MINIX_VALID_FS) 53 ms->s_state &= ~MINIX_VALID_FS; 54 minix_commit_super(sb); 55 } 56 sb->s_dirt = 0; 57} 58 59 60static void minix_put_super(struct super_block *sb) 61{ 62 int i; 63 64 if (!(sb->s_flags & MS_RDONLY)) { 65 sb->u.minix_sb.s_ms->s_state = sb->u.minix_sb.s_mount_state; 66 mark_buffer_dirty(sb->u.minix_sb.s_sbh); 67 } 68 for (i = 0; i < sb->u.minix_sb.s_imap_blocks; i++) 69 brelse(sb->u.minix_sb.s_imap[i]); 70 for (i = 0; i < sb->u.minix_sb.s_zmap_blocks; i++) 71 brelse(sb->u.minix_sb.s_zmap[i]); 72 brelse (sb->u.minix_sb.s_sbh); 73 kfree(sb->u.minix_sb.s_imap); 74 75 return; 76} 77 78static struct super_operations minix_sops = { 79 read_inode: minix_read_inode, 80 write_inode: minix_write_inode, 81 delete_inode: minix_delete_inode, 82 put_super: minix_put_super, 83 write_super: minix_write_super, 84 statfs: minix_statfs, 85 remount_fs: minix_remount, 86}; 87 88static int minix_remount (struct super_block * sb, int * flags, char * data) 89{ 90 struct minix_super_block * ms; 91 92 ms = sb->u.minix_sb.s_ms; 93 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 94 return 0; 95 if (*flags & MS_RDONLY) { 96 if (ms->s_state & MINIX_VALID_FS || 97 !(sb->u.minix_sb.s_mount_state & MINIX_VALID_FS)) 98 return 0; 99 /* Mounting a rw partition read-only. */ 100 ms->s_state = sb->u.minix_sb.s_mount_state; 101 mark_buffer_dirty(sb->u.minix_sb.s_sbh); 102 sb->s_dirt = 1; 103 minix_commit_super(sb); 104 } 105 else { 106 /* Mount a partition which is read-only, read-write. */ 107 sb->u.minix_sb.s_mount_state = ms->s_state; 108 ms->s_state &= ~MINIX_VALID_FS; 109 mark_buffer_dirty(sb->u.minix_sb.s_sbh); 110 sb->s_dirt = 1; 111 112 if (!(sb->u.minix_sb.s_mount_state & MINIX_VALID_FS)) 113 printk ("MINIX-fs warning: remounting unchecked fs, " 114 "running fsck is recommended.\n"); 115 else if ((sb->u.minix_sb.s_mount_state & MINIX_ERROR_FS)) 116 printk ("MINIX-fs warning: remounting fs with errors, " 117 "running fsck is recommended.\n"); 118 } 119 return 0; 120} 121 122static struct super_block *minix_read_super(struct super_block *s, void *data, 123 int silent) 124{ 125 struct buffer_head *bh; 126 struct buffer_head **map; 127 struct minix_super_block *ms; 128 int i, block; 129 kdev_t dev = s->s_dev; 130 struct inode *root_inode; 131 unsigned int hblock; 132 struct minix_sb_info *sbi = &s->u.minix_sb; 133 134 /* N.B. These should be compile-time tests. 135 Unfortunately that is impossible. */ 136 if (32 != sizeof (struct minix_inode)) 137 panic("bad V1 i-node size"); 138 if (64 != sizeof(struct minix2_inode)) 139 panic("bad V2 i-node size"); 140 141 hblock = get_hardsect_size(dev); 142 if (hblock > BLOCK_SIZE) 143 goto out_bad_hblock; 144 145 set_blocksize(dev, BLOCK_SIZE); 146 s->s_blocksize = BLOCK_SIZE; 147 s->s_blocksize_bits = BLOCK_SIZE_BITS; 148 if (!(bh = sb_bread(s, 1))) 149 goto out_bad_sb; 150 151 ms = (struct minix_super_block *) bh->b_data; 152 sbi->s_ms = ms; 153 sbi->s_sbh = bh; 154 sbi->s_mount_state = ms->s_state; 155 sbi->s_ninodes = ms->s_ninodes; 156 sbi->s_nzones = ms->s_nzones; 157 sbi->s_imap_blocks = ms->s_imap_blocks; 158 sbi->s_zmap_blocks = ms->s_zmap_blocks; 159 sbi->s_firstdatazone = ms->s_firstdatazone; 160 sbi->s_log_zone_size = ms->s_log_zone_size; 161 sbi->s_max_size = ms->s_max_size; 162 s->s_magic = ms->s_magic; 163 if (s->s_magic == MINIX_SUPER_MAGIC) { 164 sbi->s_version = MINIX_V1; 165 sbi->s_dirsize = 16; 166 sbi->s_namelen = 14; 167 sbi->s_link_max = MINIX_LINK_MAX; 168 } else if (s->s_magic == MINIX_SUPER_MAGIC2) { 169 sbi->s_version = MINIX_V1; 170 sbi->s_dirsize = 32; 171 sbi->s_namelen = 30; 172 sbi->s_link_max = MINIX_LINK_MAX; 173 } else if (s->s_magic == MINIX2_SUPER_MAGIC) { 174 sbi->s_version = MINIX_V2; 175 sbi->s_nzones = ms->s_zones; 176 sbi->s_dirsize = 16; 177 sbi->s_namelen = 14; 178 sbi->s_link_max = MINIX2_LINK_MAX; 179 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { 180 sbi->s_version = MINIX_V2; 181 sbi->s_nzones = ms->s_zones; 182 sbi->s_dirsize = 32; 183 sbi->s_namelen = 30; 184 sbi->s_link_max = MINIX2_LINK_MAX; 185 } else 186 goto out_no_fs; 187 188 /* 189 * Allocate the buffer map to keep the superblock small. 190 */ 191 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 192 map = kmalloc(i, GFP_KERNEL); 193 if (!map) 194 goto out_no_map; 195 memset(map, 0, i); 196 sbi->s_imap = &map[0]; 197 sbi->s_zmap = &map[sbi->s_imap_blocks]; 198 199 block=2; 200 for (i=0 ; i < sbi->s_imap_blocks ; i++) { 201 if (!(sbi->s_imap[i]=sb_bread(s, block))) 202 goto out_no_bitmap; 203 block++; 204 } 205 for (i=0 ; i < sbi->s_zmap_blocks ; i++) { 206 if (!(sbi->s_zmap[i]=sb_bread(s, block))) 207 goto out_no_bitmap; 208 block++; 209 } 210 211 minix_set_bit(0,sbi->s_imap[0]->b_data); 212 minix_set_bit(0,sbi->s_zmap[0]->b_data); 213 214 /* set up enough so that it can read an inode */ 215 s->s_op = &minix_sops; 216 root_inode = iget(s, MINIX_ROOT_INO); 217 if (!root_inode || is_bad_inode(root_inode)) 218 goto out_no_root; 219 220 s->s_root = d_alloc_root(root_inode); 221 if (!s->s_root) 222 goto out_iput; 223 224 if (!NO_TRUNCATE) 225 s->s_root->d_op = &minix_dentry_operations; 226 227 if (!(s->s_flags & MS_RDONLY)) { 228 ms->s_state &= ~MINIX_VALID_FS; 229 mark_buffer_dirty(bh); 230 s->s_dirt = 1; 231 } 232 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 233 printk ("MINIX-fs: mounting unchecked file system, " 234 "running fsck is recommended.\n"); 235 else if (sbi->s_mount_state & MINIX_ERROR_FS) 236 printk ("MINIX-fs: mounting file system with errors, " 237 "running fsck is recommended.\n"); 238 return s; 239 240out_iput: 241 iput(root_inode); 242 goto out_freemap; 243 244out_no_root: 245 if (!silent) 246 printk("MINIX-fs: get root inode failed\n"); 247 goto out_freemap; 248 249out_no_bitmap: 250 printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); 251 out_freemap: 252 for (i = 0; i < sbi->s_imap_blocks; i++) 253 brelse(sbi->s_imap[i]); 254 for (i = 0; i < sbi->s_zmap_blocks; i++) 255 brelse(sbi->s_zmap[i]); 256 kfree(sbi->s_imap); 257 goto out_release; 258 259out_no_map: 260 if (!silent) 261 printk ("MINIX-fs: can't allocate map\n"); 262 goto out_release; 263 264out_no_fs: 265 if (!silent) 266 printk("VFS: Can't find a Minix or Minix V2 filesystem on device " 267 "%s.\n", kdevname(dev)); 268 out_release: 269 brelse(bh); 270 goto out; 271 272out_bad_hblock: 273 printk("MINIX-fs: blocksize too small for device.\n"); 274 goto out; 275 276out_bad_sb: 277 printk("MINIX-fs: unable to read superblock\n"); 278 out: 279 return NULL; 280} 281 282static int minix_statfs(struct super_block *sb, struct statfs *buf) 283{ 284 buf->f_type = sb->s_magic; 285 buf->f_bsize = sb->s_blocksize; 286 buf->f_blocks = (sb->u.minix_sb.s_nzones - sb->u.minix_sb.s_firstdatazone) << sb->u.minix_sb.s_log_zone_size; 287 buf->f_bfree = minix_count_free_blocks(sb); 288 buf->f_bavail = buf->f_bfree; 289 buf->f_files = sb->u.minix_sb.s_ninodes; 290 buf->f_ffree = minix_count_free_inodes(sb); 291 buf->f_namelen = sb->u.minix_sb.s_namelen; 292 return 0; 293} 294 295static int minix_get_block(struct inode *inode, long block, 296 struct buffer_head *bh_result, int create) 297{ 298 if (INODE_VERSION(inode) == MINIX_V1) 299 return V1_minix_get_block(inode, block, bh_result, create); 300 else 301 return V2_minix_get_block(inode, block, bh_result, create); 302} 303 304static int minix_writepage(struct page *page) 305{ 306 return block_write_full_page(page,minix_get_block); 307} 308static int minix_readpage(struct file *file, struct page *page) 309{ 310 return block_read_full_page(page,minix_get_block); 311} 312static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) 313{ 314 return block_prepare_write(page,from,to,minix_get_block); 315} 316static int minix_bmap(struct address_space *mapping, long block) 317{ 318 return generic_block_bmap(mapping,block,minix_get_block); 319} 320static struct address_space_operations minix_aops = { 321 readpage: minix_readpage, 322 writepage: minix_writepage, 323 sync_page: block_sync_page, 324 prepare_write: minix_prepare_write, 325 commit_write: generic_commit_write, 326 bmap: minix_bmap 327}; 328 329void minix_set_inode(struct inode *inode, dev_t rdev) 330{ 331 if (S_ISREG(inode->i_mode)) { 332 inode->i_op = &minix_file_inode_operations; 333 inode->i_fop = &minix_file_operations; 334 inode->i_mapping->a_ops = &minix_aops; 335 } else if (S_ISDIR(inode->i_mode)) { 336 inode->i_op = &minix_dir_inode_operations; 337 inode->i_fop = &minix_dir_operations; 338 inode->i_mapping->a_ops = &minix_aops; 339 } else if (S_ISLNK(inode->i_mode)) { 340 inode->i_op = &page_symlink_inode_operations; 341 inode->i_mapping->a_ops = &minix_aops; 342 } else 343 init_special_inode(inode, inode->i_mode, rdev); 344} 345 346/* 347 * The minix V1 function to read an inode. 348 */ 349static void V1_minix_read_inode(struct inode * inode) 350{ 351 struct buffer_head * bh; 352 struct minix_inode * raw_inode; 353 int i; 354 355 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 356 if (!raw_inode) { 357 make_bad_inode(inode); 358 return; 359 } 360 inode->i_mode = raw_inode->i_mode; 361 inode->i_uid = (uid_t)raw_inode->i_uid; 362 inode->i_gid = (gid_t)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 for (i = 0; i < 9; i++) 368 inode->u.minix_i.u.i1_data[i] = raw_inode->i_zone[i]; 369 minix_set_inode(inode, raw_inode->i_zone[0]); 370 brelse(bh); 371} 372 373/* 374 * The minix V2 function to read an inode. 375 */ 376static void V2_minix_read_inode(struct inode * inode) 377{ 378 struct buffer_head * bh; 379 struct minix2_inode * raw_inode; 380 int i; 381 382 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 383 if (!raw_inode) { 384 make_bad_inode(inode); 385 return; 386 } 387 inode->i_mode = raw_inode->i_mode; 388 inode->i_uid = (uid_t)raw_inode->i_uid; 389 inode->i_gid = (gid_t)raw_inode->i_gid; 390 inode->i_nlink = raw_inode->i_nlinks; 391 inode->i_size = raw_inode->i_size; 392 inode->i_mtime = raw_inode->i_mtime; 393 inode->i_atime = raw_inode->i_atime; 394 inode->i_ctime = raw_inode->i_ctime; 395 inode->i_blocks = inode->i_blksize = 0; 396 for (i = 0; i < 10; i++) 397 inode->u.minix_i.u.i2_data[i] = raw_inode->i_zone[i]; 398 minix_set_inode(inode, raw_inode->i_zone[0]); 399 brelse(bh); 400} 401 402/* 403 * The global function to read an inode. 404 */ 405static void minix_read_inode(struct inode * inode) 406{ 407 if (INODE_VERSION(inode) == MINIX_V1) 408 V1_minix_read_inode(inode); 409 else 410 V2_minix_read_inode(inode); 411} 412 413/* 414 * The minix V1 function to synchronize an inode. 415 */ 416static struct buffer_head * V1_minix_update_inode(struct inode * inode) 417{ 418 struct buffer_head * bh; 419 struct minix_inode * raw_inode; 420 int i; 421 422 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 423 if (!raw_inode) 424 return 0; 425 raw_inode->i_mode = inode->i_mode; 426 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 427 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 428 raw_inode->i_nlinks = inode->i_nlink; 429 raw_inode->i_size = inode->i_size; 430 raw_inode->i_time = inode->i_mtime; 431 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 432 raw_inode->i_zone[0] = kdev_t_to_nr(inode->i_rdev); 433 else for (i = 0; i < 9; i++) 434 raw_inode->i_zone[i] = inode->u.minix_i.u.i1_data[i]; 435 mark_buffer_dirty(bh); 436 return bh; 437} 438 439/* 440 * The minix V2 function to synchronize an inode. 441 */ 442static struct buffer_head * V2_minix_update_inode(struct inode * inode) 443{ 444 struct buffer_head * bh; 445 struct minix2_inode * raw_inode; 446 int i; 447 448 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 449 if (!raw_inode) 450 return 0; 451 raw_inode->i_mode = inode->i_mode; 452 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 453 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 454 raw_inode->i_nlinks = inode->i_nlink; 455 raw_inode->i_size = inode->i_size; 456 raw_inode->i_mtime = inode->i_mtime; 457 raw_inode->i_atime = inode->i_atime; 458 raw_inode->i_ctime = inode->i_ctime; 459 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 460 raw_inode->i_zone[0] = kdev_t_to_nr(inode->i_rdev); 461 else for (i = 0; i < 10; i++) 462 raw_inode->i_zone[i] = inode->u.minix_i.u.i2_data[i]; 463 mark_buffer_dirty(bh); 464 return bh; 465} 466 467static struct buffer_head *minix_update_inode(struct inode *inode) 468{ 469 if (INODE_VERSION(inode) == MINIX_V1) 470 return V1_minix_update_inode(inode); 471 else 472 return V2_minix_update_inode(inode); 473} 474 475static void minix_write_inode(struct inode * inode, int wait) 476{ 477 struct buffer_head *bh; 478 479 lock_kernel(); 480 bh = minix_update_inode(inode); 481 unlock_kernel(); 482 brelse(bh); 483} 484 485int minix_sync_inode(struct inode * inode) 486{ 487 int err = 0; 488 struct buffer_head *bh; 489 490 bh = minix_update_inode(inode); 491 if (bh && buffer_dirty(bh)) 492 { 493 ll_rw_block(WRITE, 1, &bh); 494 wait_on_buffer(bh); 495 if (buffer_req(bh) && !buffer_uptodate(bh)) 496 { 497 printk ("IO error syncing minix inode [" 498 "%s:%08lx]\n", 499 kdevname(inode->i_dev), inode->i_ino); 500 err = -1; 501 } 502 } 503 else if (!bh) 504 err = -1; 505 brelse (bh); 506 return err; 507} 508 509/* 510 * The function that is called for file truncation. 511 */ 512void minix_truncate(struct inode * inode) 513{ 514 if (INODE_VERSION(inode) == MINIX_V1) 515 V1_minix_truncate(inode); 516 else 517 V2_minix_truncate(inode); 518} 519 520static DECLARE_FSTYPE_DEV(minix_fs_type,"minix",minix_read_super); 521 522static int __init init_minix_fs(void) 523{ 524 return register_filesystem(&minix_fs_type); 525} 526 527static void __exit exit_minix_fs(void) 528{ 529 unregister_filesystem(&minix_fs_type); 530} 531 532EXPORT_NO_SYMBOLS; 533 534module_init(init_minix_fs) 535module_exit(exit_minix_fs) 536MODULE_LICENSE("GPL"); 537 538