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 #include "minix.h" 14 #include <linux/buffer_head.h> 15 #include <linux/slab.h> 16 #include <linux/init.h> 17 #include <linux/highuid.h> 18 #include <linux/vfs.h> 19 20 static void minix_read_inode(struct inode * inode); 21 static int minix_write_inode(struct inode * inode, int wait); 22 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf); 23 static int minix_remount (struct super_block * sb, int * flags, char * data); 24 25 static void minix_delete_inode(struct inode *inode) 26 { 27 truncate_inode_pages(&inode->i_data, 0); 28 inode->i_size = 0; 29 minix_truncate(inode); 30 minix_free_inode(inode); 31 } 32 33 static void minix_put_super(struct super_block *sb) 34 { 35 int i; 36 struct minix_sb_info *sbi = minix_sb(sb); 37 38 if (!(sb->s_flags & MS_RDONLY)) { 39 sbi->s_ms->s_state = sbi->s_mount_state; 40 mark_buffer_dirty(sbi->s_sbh); 41 } 42 for (i = 0; i < sbi->s_imap_blocks; i++) 43 brelse(sbi->s_imap[i]); 44 for (i = 0; i < sbi->s_zmap_blocks; i++) 45 brelse(sbi->s_zmap[i]); 46 brelse (sbi->s_sbh); 47 kfree(sbi->s_imap); 48 sb->s_fs_info = NULL; 49 kfree(sbi); 50 51 return; 52 } 53 54 static kmem_cache_t * minix_inode_cachep; 55 56 static struct inode *minix_alloc_inode(struct super_block *sb) 57 { 58 struct minix_inode_info *ei; 59 ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, SLAB_KERNEL); 60 if (!ei) 61 return NULL; 62 return &ei->vfs_inode; 63 } 64 65 static void minix_destroy_inode(struct inode *inode) 66 { 67 kmem_cache_free(minix_inode_cachep, minix_i(inode)); 68 } 69 70 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) 71 { 72 struct minix_inode_info *ei = (struct minix_inode_info *) foo; 73 74 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 75 SLAB_CTOR_CONSTRUCTOR) 76 inode_init_once(&ei->vfs_inode); 77 } 78 79 static int init_inodecache(void) 80 { 81 minix_inode_cachep = kmem_cache_create("minix_inode_cache", 82 sizeof(struct minix_inode_info), 83 0, (SLAB_RECLAIM_ACCOUNT| 84 SLAB_MEM_SPREAD), 85 init_once, NULL); 86 if (minix_inode_cachep == NULL) 87 return -ENOMEM; 88 return 0; 89 } 90 91 static void destroy_inodecache(void) 92 { 93 kmem_cache_destroy(minix_inode_cachep); 94 } 95 96 static struct super_operations minix_sops = { 97 .alloc_inode = minix_alloc_inode, 98 .destroy_inode = minix_destroy_inode, 99 .read_inode = minix_read_inode, 100 .write_inode = minix_write_inode, 101 .delete_inode = minix_delete_inode, 102 .put_super = minix_put_super, 103 .statfs = minix_statfs, 104 .remount_fs = minix_remount, 105 }; 106 107 static int minix_remount (struct super_block * sb, int * flags, char * data) 108 { 109 struct minix_sb_info * sbi = minix_sb(sb); 110 struct minix_super_block * ms; 111 112 ms = sbi->s_ms; 113 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 114 return 0; 115 if (*flags & MS_RDONLY) { 116 if (ms->s_state & MINIX_VALID_FS || 117 !(sbi->s_mount_state & MINIX_VALID_FS)) 118 return 0; 119 /* Mounting a rw partition read-only. */ 120 ms->s_state = sbi->s_mount_state; 121 mark_buffer_dirty(sbi->s_sbh); 122 } else { 123 /* Mount a partition which is read-only, read-write. */ 124 sbi->s_mount_state = ms->s_state; 125 ms->s_state &= ~MINIX_VALID_FS; 126 mark_buffer_dirty(sbi->s_sbh); 127 128 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 129 printk("MINIX-fs warning: remounting unchecked fs, " 130 "running fsck is recommended\n"); 131 else if ((sbi->s_mount_state & MINIX_ERROR_FS)) 132 printk("MINIX-fs warning: remounting fs with errors, " 133 "running fsck is recommended\n"); 134 } 135 return 0; 136 } 137 138 static int minix_fill_super(struct super_block *s, void *data, int silent) 139 { 140 struct buffer_head *bh; 141 struct buffer_head **map; 142 struct minix_super_block *ms; 143 int i, block; 144 struct inode *root_inode; 145 struct minix_sb_info *sbi; 146 147 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL); 148 if (!sbi) 149 return -ENOMEM; 150 s->s_fs_info = sbi; 151 152 /* N.B. These should be compile-time tests. 153 Unfortunately that is impossible. */ 154 if (32 != sizeof (struct minix_inode)) 155 panic("bad V1 i-node size"); 156 if (64 != sizeof(struct minix2_inode)) 157 panic("bad V2 i-node size"); 158 159 if (!sb_set_blocksize(s, BLOCK_SIZE)) 160 goto out_bad_hblock; 161 162 if (!(bh = sb_bread(s, 1))) 163 goto out_bad_sb; 164 165 ms = (struct minix_super_block *) bh->b_data; 166 sbi->s_ms = ms; 167 sbi->s_sbh = bh; 168 sbi->s_mount_state = ms->s_state; 169 sbi->s_ninodes = ms->s_ninodes; 170 sbi->s_nzones = ms->s_nzones; 171 sbi->s_imap_blocks = ms->s_imap_blocks; 172 sbi->s_zmap_blocks = ms->s_zmap_blocks; 173 sbi->s_firstdatazone = ms->s_firstdatazone; 174 sbi->s_log_zone_size = ms->s_log_zone_size; 175 sbi->s_max_size = ms->s_max_size; 176 s->s_magic = ms->s_magic; 177 if (s->s_magic == MINIX_SUPER_MAGIC) { 178 sbi->s_version = MINIX_V1; 179 sbi->s_dirsize = 16; 180 sbi->s_namelen = 14; 181 sbi->s_link_max = MINIX_LINK_MAX; 182 } else if (s->s_magic == MINIX_SUPER_MAGIC2) { 183 sbi->s_version = MINIX_V1; 184 sbi->s_dirsize = 32; 185 sbi->s_namelen = 30; 186 sbi->s_link_max = MINIX_LINK_MAX; 187 } else if (s->s_magic == MINIX2_SUPER_MAGIC) { 188 sbi->s_version = MINIX_V2; 189 sbi->s_nzones = ms->s_zones; 190 sbi->s_dirsize = 16; 191 sbi->s_namelen = 14; 192 sbi->s_link_max = MINIX2_LINK_MAX; 193 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { 194 sbi->s_version = MINIX_V2; 195 sbi->s_nzones = ms->s_zones; 196 sbi->s_dirsize = 32; 197 sbi->s_namelen = 30; 198 sbi->s_link_max = MINIX2_LINK_MAX; 199 } else 200 goto out_no_fs; 201 202 /* 203 * Allocate the buffer map to keep the superblock small. 204 */ 205 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0) 206 goto out_illegal_sb; 207 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 208 map = kzalloc(i, GFP_KERNEL); 209 if (!map) 210 goto out_no_map; 211 sbi->s_imap = &map[0]; 212 sbi->s_zmap = &map[sbi->s_imap_blocks]; 213 214 block=2; 215 for (i=0 ; i < sbi->s_imap_blocks ; i++) { 216 if (!(sbi->s_imap[i]=sb_bread(s, block))) 217 goto out_no_bitmap; 218 block++; 219 } 220 for (i=0 ; i < sbi->s_zmap_blocks ; i++) { 221 if (!(sbi->s_zmap[i]=sb_bread(s, block))) 222 goto out_no_bitmap; 223 block++; 224 } 225 226 minix_set_bit(0,sbi->s_imap[0]->b_data); 227 minix_set_bit(0,sbi->s_zmap[0]->b_data); 228 229 /* set up enough so that it can read an inode */ 230 s->s_op = &minix_sops; 231 root_inode = iget(s, MINIX_ROOT_INO); 232 if (!root_inode || is_bad_inode(root_inode)) 233 goto out_no_root; 234 235 s->s_root = d_alloc_root(root_inode); 236 if (!s->s_root) 237 goto out_iput; 238 239 if (!NO_TRUNCATE) 240 s->s_root->d_op = &minix_dentry_operations; 241 242 if (!(s->s_flags & MS_RDONLY)) { 243 ms->s_state &= ~MINIX_VALID_FS; 244 mark_buffer_dirty(bh); 245 } 246 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 247 printk("MINIX-fs: mounting unchecked file system, " 248 "running fsck is recommended\n"); 249 else if (sbi->s_mount_state & MINIX_ERROR_FS) 250 printk("MINIX-fs: mounting file system with errors, " 251 "running fsck is recommended\n"); 252 return 0; 253 254 out_iput: 255 iput(root_inode); 256 goto out_freemap; 257 258 out_no_root: 259 if (!silent) 260 printk("MINIX-fs: get root inode failed\n"); 261 goto out_freemap; 262 263 out_no_bitmap: 264 printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); 265 out_freemap: 266 for (i = 0; i < sbi->s_imap_blocks; i++) 267 brelse(sbi->s_imap[i]); 268 for (i = 0; i < sbi->s_zmap_blocks; i++) 269 brelse(sbi->s_zmap[i]); 270 kfree(sbi->s_imap); 271 goto out_release; 272 273 out_no_map: 274 if (!silent) 275 printk("MINIX-fs: can't allocate map\n"); 276 goto out_release; 277 278 out_illegal_sb: 279 if (!silent) 280 printk("MINIX-fs: bad superblock\n"); 281 goto out_release; 282 283 out_no_fs: 284 if (!silent) 285 printk("VFS: Can't find a Minix or Minix V2 filesystem " 286 "on device %s\n", s->s_id); 287 out_release: 288 brelse(bh); 289 goto out; 290 291 out_bad_hblock: 292 printk("MINIX-fs: blocksize too small for device\n"); 293 goto out; 294 295 out_bad_sb: 296 printk("MINIX-fs: unable to read superblock\n"); 297 out: 298 s->s_fs_info = NULL; 299 kfree(sbi); 300 return -EINVAL; 301 } 302 303 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf) 304 { 305 struct minix_sb_info *sbi = minix_sb(dentry->d_sb); 306 buf->f_type = dentry->d_sb->s_magic; 307 buf->f_bsize = dentry->d_sb->s_blocksize; 308 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; 309 buf->f_bfree = minix_count_free_blocks(sbi); 310 buf->f_bavail = buf->f_bfree; 311 buf->f_files = sbi->s_ninodes; 312 buf->f_ffree = minix_count_free_inodes(sbi); 313 buf->f_namelen = sbi->s_namelen; 314 return 0; 315 } 316 317 static int minix_get_block(struct inode *inode, sector_t block, 318 struct buffer_head *bh_result, int create) 319 { 320 if (INODE_VERSION(inode) == MINIX_V1) 321 return V1_minix_get_block(inode, block, bh_result, create); 322 else 323 return V2_minix_get_block(inode, block, bh_result, create); 324 } 325 326 static int minix_writepage(struct page *page, struct writeback_control *wbc) 327 { 328 return block_write_full_page(page, minix_get_block, wbc); 329 } 330 static int minix_readpage(struct file *file, struct page *page) 331 { 332 return block_read_full_page(page,minix_get_block); 333 } 334 static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) 335 { 336 return block_prepare_write(page,from,to,minix_get_block); 337 } 338 static sector_t minix_bmap(struct address_space *mapping, sector_t block) 339 { 340 return generic_block_bmap(mapping,block,minix_get_block); 341 } 342 static const struct address_space_operations minix_aops = { 343 .readpage = minix_readpage, 344 .writepage = minix_writepage, 345 .sync_page = block_sync_page, 346 .prepare_write = minix_prepare_write, 347 .commit_write = generic_commit_write, 348 .bmap = minix_bmap 349 }; 350 351 static struct inode_operations minix_symlink_inode_operations = { 352 .readlink = generic_readlink, 353 .follow_link = page_follow_link_light, 354 .put_link = page_put_link, 355 .getattr = minix_getattr, 356 }; 357 358 void minix_set_inode(struct inode *inode, dev_t rdev) 359 { 360 if (S_ISREG(inode->i_mode)) { 361 inode->i_op = &minix_file_inode_operations; 362 inode->i_fop = &minix_file_operations; 363 inode->i_mapping->a_ops = &minix_aops; 364 } else if (S_ISDIR(inode->i_mode)) { 365 inode->i_op = &minix_dir_inode_operations; 366 inode->i_fop = &minix_dir_operations; 367 inode->i_mapping->a_ops = &minix_aops; 368 } else if (S_ISLNK(inode->i_mode)) { 369 inode->i_op = &minix_symlink_inode_operations; 370 inode->i_mapping->a_ops = &minix_aops; 371 } else 372 init_special_inode(inode, inode->i_mode, rdev); 373 } 374 375 /* 376 * The minix V1 function to read an inode. 377 */ 378 static void V1_minix_read_inode(struct inode * inode) 379 { 380 struct buffer_head * bh; 381 struct minix_inode * raw_inode; 382 struct minix_inode_info *minix_inode = minix_i(inode); 383 int i; 384 385 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 386 if (!raw_inode) { 387 make_bad_inode(inode); 388 return; 389 } 390 inode->i_mode = raw_inode->i_mode; 391 inode->i_uid = (uid_t)raw_inode->i_uid; 392 inode->i_gid = (gid_t)raw_inode->i_gid; 393 inode->i_nlink = raw_inode->i_nlinks; 394 inode->i_size = raw_inode->i_size; 395 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; 396 inode->i_mtime.tv_nsec = 0; 397 inode->i_atime.tv_nsec = 0; 398 inode->i_ctime.tv_nsec = 0; 399 inode->i_blocks = inode->i_blksize = 0; 400 for (i = 0; i < 9; i++) 401 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 402 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 403 brelse(bh); 404 } 405 406 /* 407 * The minix V2 function to read an inode. 408 */ 409 static void V2_minix_read_inode(struct inode * inode) 410 { 411 struct buffer_head * bh; 412 struct minix2_inode * raw_inode; 413 struct minix_inode_info *minix_inode = minix_i(inode); 414 int i; 415 416 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 417 if (!raw_inode) { 418 make_bad_inode(inode); 419 return; 420 } 421 inode->i_mode = raw_inode->i_mode; 422 inode->i_uid = (uid_t)raw_inode->i_uid; 423 inode->i_gid = (gid_t)raw_inode->i_gid; 424 inode->i_nlink = raw_inode->i_nlinks; 425 inode->i_size = raw_inode->i_size; 426 inode->i_mtime.tv_sec = raw_inode->i_mtime; 427 inode->i_atime.tv_sec = raw_inode->i_atime; 428 inode->i_ctime.tv_sec = raw_inode->i_ctime; 429 inode->i_mtime.tv_nsec = 0; 430 inode->i_atime.tv_nsec = 0; 431 inode->i_ctime.tv_nsec = 0; 432 inode->i_blocks = inode->i_blksize = 0; 433 for (i = 0; i < 10; i++) 434 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 435 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 436 brelse(bh); 437 } 438 439 /* 440 * The global function to read an inode. 441 */ 442 static void minix_read_inode(struct inode * inode) 443 { 444 if (INODE_VERSION(inode) == MINIX_V1) 445 V1_minix_read_inode(inode); 446 else 447 V2_minix_read_inode(inode); 448 } 449 450 /* 451 * The minix V1 function to synchronize an inode. 452 */ 453 static struct buffer_head * V1_minix_update_inode(struct inode * inode) 454 { 455 struct buffer_head * bh; 456 struct minix_inode * raw_inode; 457 struct minix_inode_info *minix_inode = minix_i(inode); 458 int i; 459 460 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 461 if (!raw_inode) 462 return NULL; 463 raw_inode->i_mode = inode->i_mode; 464 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 465 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 466 raw_inode->i_nlinks = inode->i_nlink; 467 raw_inode->i_size = inode->i_size; 468 raw_inode->i_time = inode->i_mtime.tv_sec; 469 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 470 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 471 else for (i = 0; i < 9; i++) 472 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 473 mark_buffer_dirty(bh); 474 return bh; 475 } 476 477 /* 478 * The minix V2 function to synchronize an inode. 479 */ 480 static struct buffer_head * V2_minix_update_inode(struct inode * inode) 481 { 482 struct buffer_head * bh; 483 struct minix2_inode * raw_inode; 484 struct minix_inode_info *minix_inode = minix_i(inode); 485 int i; 486 487 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 488 if (!raw_inode) 489 return NULL; 490 raw_inode->i_mode = inode->i_mode; 491 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 492 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 493 raw_inode->i_nlinks = inode->i_nlink; 494 raw_inode->i_size = inode->i_size; 495 raw_inode->i_mtime = inode->i_mtime.tv_sec; 496 raw_inode->i_atime = inode->i_atime.tv_sec; 497 raw_inode->i_ctime = inode->i_ctime.tv_sec; 498 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 499 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 500 else for (i = 0; i < 10; i++) 501 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 502 mark_buffer_dirty(bh); 503 return bh; 504 } 505 506 static struct buffer_head *minix_update_inode(struct inode *inode) 507 { 508 if (INODE_VERSION(inode) == MINIX_V1) 509 return V1_minix_update_inode(inode); 510 else 511 return V2_minix_update_inode(inode); 512 } 513 514 static int minix_write_inode(struct inode * inode, int wait) 515 { 516 brelse(minix_update_inode(inode)); 517 return 0; 518 } 519 520 int minix_sync_inode(struct inode * inode) 521 { 522 int err = 0; 523 struct buffer_head *bh; 524 525 bh = minix_update_inode(inode); 526 if (bh && buffer_dirty(bh)) 527 { 528 sync_dirty_buffer(bh); 529 if (buffer_req(bh) && !buffer_uptodate(bh)) 530 { 531 printk("IO error syncing minix inode [%s:%08lx]\n", 532 inode->i_sb->s_id, inode->i_ino); 533 err = -1; 534 } 535 } 536 else if (!bh) 537 err = -1; 538 brelse (bh); 539 return err; 540 } 541 542 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 543 { 544 generic_fillattr(dentry->d_inode, stat); 545 if (INODE_VERSION(dentry->d_inode) == MINIX_V1) 546 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size); 547 else 548 stat->blocks = (BLOCK_SIZE / 512) * V2_minix_blocks(stat->size); 549 stat->blksize = BLOCK_SIZE; 550 return 0; 551 } 552 553 /* 554 * The function that is called for file truncation. 555 */ 556 void minix_truncate(struct inode * inode) 557 { 558 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 559 return; 560 if (INODE_VERSION(inode) == MINIX_V1) 561 V1_minix_truncate(inode); 562 else 563 V2_minix_truncate(inode); 564 } 565 566 static int minix_get_sb(struct file_system_type *fs_type, 567 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 568 { 569 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super, 570 mnt); 571 } 572 573 static struct file_system_type minix_fs_type = { 574 .owner = THIS_MODULE, 575 .name = "minix", 576 .get_sb = minix_get_sb, 577 .kill_sb = kill_block_super, 578 .fs_flags = FS_REQUIRES_DEV, 579 }; 580 581 static int __init init_minix_fs(void) 582 { 583 int err = init_inodecache(); 584 if (err) 585 goto out1; 586 err = register_filesystem(&minix_fs_type); 587 if (err) 588 goto out; 589 return 0; 590 out: 591 destroy_inodecache(); 592 out1: 593 return err; 594 } 595 596 static void __exit exit_minix_fs(void) 597 { 598 unregister_filesystem(&minix_fs_type); 599 destroy_inodecache(); 600 } 601 602 module_init(init_minix_fs) 603 module_exit(exit_minix_fs) 604 MODULE_LICENSE("GPL"); 605 606