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 if (kmem_cache_destroy(minix_inode_cachep)) 94 printk(KERN_INFO "minix_inode_cache: not all structures were freed\n"); 95 } 96 97 static struct super_operations minix_sops = { 98 .alloc_inode = minix_alloc_inode, 99 .destroy_inode = minix_destroy_inode, 100 .read_inode = minix_read_inode, 101 .write_inode = minix_write_inode, 102 .delete_inode = minix_delete_inode, 103 .put_super = minix_put_super, 104 .statfs = minix_statfs, 105 .remount_fs = minix_remount, 106 }; 107 108 static int minix_remount (struct super_block * sb, int * flags, char * data) 109 { 110 struct minix_sb_info * sbi = minix_sb(sb); 111 struct minix_super_block * ms; 112 113 ms = sbi->s_ms; 114 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 115 return 0; 116 if (*flags & MS_RDONLY) { 117 if (ms->s_state & MINIX_VALID_FS || 118 !(sbi->s_mount_state & MINIX_VALID_FS)) 119 return 0; 120 /* Mounting a rw partition read-only. */ 121 ms->s_state = sbi->s_mount_state; 122 mark_buffer_dirty(sbi->s_sbh); 123 } else { 124 /* Mount a partition which is read-only, read-write. */ 125 sbi->s_mount_state = ms->s_state; 126 ms->s_state &= ~MINIX_VALID_FS; 127 mark_buffer_dirty(sbi->s_sbh); 128 129 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 130 printk("MINIX-fs warning: remounting unchecked fs, " 131 "running fsck is recommended\n"); 132 else if ((sbi->s_mount_state & MINIX_ERROR_FS)) 133 printk("MINIX-fs warning: remounting fs with errors, " 134 "running fsck is recommended\n"); 135 } 136 return 0; 137 } 138 139 static int minix_fill_super(struct super_block *s, void *data, int silent) 140 { 141 struct buffer_head *bh; 142 struct buffer_head **map; 143 struct minix_super_block *ms; 144 int i, block; 145 struct inode *root_inode; 146 struct minix_sb_info *sbi; 147 148 sbi = kmalloc(sizeof(struct minix_sb_info), GFP_KERNEL); 149 if (!sbi) 150 return -ENOMEM; 151 s->s_fs_info = sbi; 152 memset(sbi, 0, sizeof(struct minix_sb_info)); 153 154 /* N.B. These should be compile-time tests. 155 Unfortunately that is impossible. */ 156 if (32 != sizeof (struct minix_inode)) 157 panic("bad V1 i-node size"); 158 if (64 != sizeof(struct minix2_inode)) 159 panic("bad V2 i-node size"); 160 161 if (!sb_set_blocksize(s, BLOCK_SIZE)) 162 goto out_bad_hblock; 163 164 if (!(bh = sb_bread(s, 1))) 165 goto out_bad_sb; 166 167 ms = (struct minix_super_block *) bh->b_data; 168 sbi->s_ms = ms; 169 sbi->s_sbh = bh; 170 sbi->s_mount_state = ms->s_state; 171 sbi->s_ninodes = ms->s_ninodes; 172 sbi->s_nzones = ms->s_nzones; 173 sbi->s_imap_blocks = ms->s_imap_blocks; 174 sbi->s_zmap_blocks = ms->s_zmap_blocks; 175 sbi->s_firstdatazone = ms->s_firstdatazone; 176 sbi->s_log_zone_size = ms->s_log_zone_size; 177 sbi->s_max_size = ms->s_max_size; 178 s->s_magic = ms->s_magic; 179 if (s->s_magic == MINIX_SUPER_MAGIC) { 180 sbi->s_version = MINIX_V1; 181 sbi->s_dirsize = 16; 182 sbi->s_namelen = 14; 183 sbi->s_link_max = MINIX_LINK_MAX; 184 } else if (s->s_magic == MINIX_SUPER_MAGIC2) { 185 sbi->s_version = MINIX_V1; 186 sbi->s_dirsize = 32; 187 sbi->s_namelen = 30; 188 sbi->s_link_max = MINIX_LINK_MAX; 189 } else if (s->s_magic == MINIX2_SUPER_MAGIC) { 190 sbi->s_version = MINIX_V2; 191 sbi->s_nzones = ms->s_zones; 192 sbi->s_dirsize = 16; 193 sbi->s_namelen = 14; 194 sbi->s_link_max = MINIX2_LINK_MAX; 195 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { 196 sbi->s_version = MINIX_V2; 197 sbi->s_nzones = ms->s_zones; 198 sbi->s_dirsize = 32; 199 sbi->s_namelen = 30; 200 sbi->s_link_max = MINIX2_LINK_MAX; 201 } else 202 goto out_no_fs; 203 204 /* 205 * Allocate the buffer map to keep the superblock small. 206 */ 207 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0) 208 goto out_illegal_sb; 209 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 210 map = kmalloc(i, GFP_KERNEL); 211 if (!map) 212 goto out_no_map; 213 memset(map, 0, i); 214 sbi->s_imap = &map[0]; 215 sbi->s_zmap = &map[sbi->s_imap_blocks]; 216 217 block=2; 218 for (i=0 ; i < sbi->s_imap_blocks ; i++) { 219 if (!(sbi->s_imap[i]=sb_bread(s, block))) 220 goto out_no_bitmap; 221 block++; 222 } 223 for (i=0 ; i < sbi->s_zmap_blocks ; i++) { 224 if (!(sbi->s_zmap[i]=sb_bread(s, block))) 225 goto out_no_bitmap; 226 block++; 227 } 228 229 minix_set_bit(0,sbi->s_imap[0]->b_data); 230 minix_set_bit(0,sbi->s_zmap[0]->b_data); 231 232 /* set up enough so that it can read an inode */ 233 s->s_op = &minix_sops; 234 root_inode = iget(s, MINIX_ROOT_INO); 235 if (!root_inode || is_bad_inode(root_inode)) 236 goto out_no_root; 237 238 s->s_root = d_alloc_root(root_inode); 239 if (!s->s_root) 240 goto out_iput; 241 242 if (!NO_TRUNCATE) 243 s->s_root->d_op = &minix_dentry_operations; 244 245 if (!(s->s_flags & MS_RDONLY)) { 246 ms->s_state &= ~MINIX_VALID_FS; 247 mark_buffer_dirty(bh); 248 } 249 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 250 printk("MINIX-fs: mounting unchecked file system, " 251 "running fsck is recommended\n"); 252 else if (sbi->s_mount_state & MINIX_ERROR_FS) 253 printk("MINIX-fs: mounting file system with errors, " 254 "running fsck is recommended\n"); 255 return 0; 256 257 out_iput: 258 iput(root_inode); 259 goto out_freemap; 260 261 out_no_root: 262 if (!silent) 263 printk("MINIX-fs: get root inode failed\n"); 264 goto out_freemap; 265 266 out_no_bitmap: 267 printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); 268 out_freemap: 269 for (i = 0; i < sbi->s_imap_blocks; i++) 270 brelse(sbi->s_imap[i]); 271 for (i = 0; i < sbi->s_zmap_blocks; i++) 272 brelse(sbi->s_zmap[i]); 273 kfree(sbi->s_imap); 274 goto out_release; 275 276 out_no_map: 277 if (!silent) 278 printk("MINIX-fs: can't allocate map\n"); 279 goto out_release; 280 281 out_illegal_sb: 282 if (!silent) 283 printk("MINIX-fs: bad superblock\n"); 284 goto out_release; 285 286 out_no_fs: 287 if (!silent) 288 printk("VFS: Can't find a Minix or Minix V2 filesystem " 289 "on device %s\n", s->s_id); 290 out_release: 291 brelse(bh); 292 goto out; 293 294 out_bad_hblock: 295 printk("MINIX-fs: blocksize too small for device\n"); 296 goto out; 297 298 out_bad_sb: 299 printk("MINIX-fs: unable to read superblock\n"); 300 out: 301 s->s_fs_info = NULL; 302 kfree(sbi); 303 return -EINVAL; 304 } 305 306 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf) 307 { 308 struct minix_sb_info *sbi = minix_sb(dentry->d_sb); 309 buf->f_type = dentry->d_sb->s_magic; 310 buf->f_bsize = dentry->d_sb->s_blocksize; 311 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; 312 buf->f_bfree = minix_count_free_blocks(sbi); 313 buf->f_bavail = buf->f_bfree; 314 buf->f_files = sbi->s_ninodes; 315 buf->f_ffree = minix_count_free_inodes(sbi); 316 buf->f_namelen = sbi->s_namelen; 317 return 0; 318 } 319 320 static int minix_get_block(struct inode *inode, sector_t block, 321 struct buffer_head *bh_result, int create) 322 { 323 if (INODE_VERSION(inode) == MINIX_V1) 324 return V1_minix_get_block(inode, block, bh_result, create); 325 else 326 return V2_minix_get_block(inode, block, bh_result, create); 327 } 328 329 static int minix_writepage(struct page *page, struct writeback_control *wbc) 330 { 331 return block_write_full_page(page, minix_get_block, wbc); 332 } 333 static int minix_readpage(struct file *file, struct page *page) 334 { 335 return block_read_full_page(page,minix_get_block); 336 } 337 static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) 338 { 339 return block_prepare_write(page,from,to,minix_get_block); 340 } 341 static sector_t minix_bmap(struct address_space *mapping, sector_t block) 342 { 343 return generic_block_bmap(mapping,block,minix_get_block); 344 } 345 static const struct address_space_operations minix_aops = { 346 .readpage = minix_readpage, 347 .writepage = minix_writepage, 348 .sync_page = block_sync_page, 349 .prepare_write = minix_prepare_write, 350 .commit_write = generic_commit_write, 351 .bmap = minix_bmap 352 }; 353 354 static struct inode_operations minix_symlink_inode_operations = { 355 .readlink = generic_readlink, 356 .follow_link = page_follow_link_light, 357 .put_link = page_put_link, 358 .getattr = minix_getattr, 359 }; 360 361 void minix_set_inode(struct inode *inode, dev_t rdev) 362 { 363 if (S_ISREG(inode->i_mode)) { 364 inode->i_op = &minix_file_inode_operations; 365 inode->i_fop = &minix_file_operations; 366 inode->i_mapping->a_ops = &minix_aops; 367 } else if (S_ISDIR(inode->i_mode)) { 368 inode->i_op = &minix_dir_inode_operations; 369 inode->i_fop = &minix_dir_operations; 370 inode->i_mapping->a_ops = &minix_aops; 371 } else if (S_ISLNK(inode->i_mode)) { 372 inode->i_op = &minix_symlink_inode_operations; 373 inode->i_mapping->a_ops = &minix_aops; 374 } else 375 init_special_inode(inode, inode->i_mode, rdev); 376 } 377 378 /* 379 * The minix V1 function to read an inode. 380 */ 381 static void V1_minix_read_inode(struct inode * inode) 382 { 383 struct buffer_head * bh; 384 struct minix_inode * raw_inode; 385 struct minix_inode_info *minix_inode = minix_i(inode); 386 int i; 387 388 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 389 if (!raw_inode) { 390 make_bad_inode(inode); 391 return; 392 } 393 inode->i_mode = raw_inode->i_mode; 394 inode->i_uid = (uid_t)raw_inode->i_uid; 395 inode->i_gid = (gid_t)raw_inode->i_gid; 396 inode->i_nlink = raw_inode->i_nlinks; 397 inode->i_size = raw_inode->i_size; 398 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; 399 inode->i_mtime.tv_nsec = 0; 400 inode->i_atime.tv_nsec = 0; 401 inode->i_ctime.tv_nsec = 0; 402 inode->i_blocks = inode->i_blksize = 0; 403 for (i = 0; i < 9; i++) 404 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 405 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 406 brelse(bh); 407 } 408 409 /* 410 * The minix V2 function to read an inode. 411 */ 412 static void V2_minix_read_inode(struct inode * inode) 413 { 414 struct buffer_head * bh; 415 struct minix2_inode * raw_inode; 416 struct minix_inode_info *minix_inode = minix_i(inode); 417 int i; 418 419 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 420 if (!raw_inode) { 421 make_bad_inode(inode); 422 return; 423 } 424 inode->i_mode = raw_inode->i_mode; 425 inode->i_uid = (uid_t)raw_inode->i_uid; 426 inode->i_gid = (gid_t)raw_inode->i_gid; 427 inode->i_nlink = raw_inode->i_nlinks; 428 inode->i_size = raw_inode->i_size; 429 inode->i_mtime.tv_sec = raw_inode->i_mtime; 430 inode->i_atime.tv_sec = raw_inode->i_atime; 431 inode->i_ctime.tv_sec = raw_inode->i_ctime; 432 inode->i_mtime.tv_nsec = 0; 433 inode->i_atime.tv_nsec = 0; 434 inode->i_ctime.tv_nsec = 0; 435 inode->i_blocks = inode->i_blksize = 0; 436 for (i = 0; i < 10; i++) 437 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 438 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 439 brelse(bh); 440 } 441 442 /* 443 * The global function to read an inode. 444 */ 445 static void minix_read_inode(struct inode * inode) 446 { 447 if (INODE_VERSION(inode) == MINIX_V1) 448 V1_minix_read_inode(inode); 449 else 450 V2_minix_read_inode(inode); 451 } 452 453 /* 454 * The minix V1 function to synchronize an inode. 455 */ 456 static struct buffer_head * V1_minix_update_inode(struct inode * inode) 457 { 458 struct buffer_head * bh; 459 struct minix_inode * raw_inode; 460 struct minix_inode_info *minix_inode = minix_i(inode); 461 int i; 462 463 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 464 if (!raw_inode) 465 return NULL; 466 raw_inode->i_mode = inode->i_mode; 467 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 468 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 469 raw_inode->i_nlinks = inode->i_nlink; 470 raw_inode->i_size = inode->i_size; 471 raw_inode->i_time = inode->i_mtime.tv_sec; 472 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 473 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 474 else for (i = 0; i < 9; i++) 475 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 476 mark_buffer_dirty(bh); 477 return bh; 478 } 479 480 /* 481 * The minix V2 function to synchronize an inode. 482 */ 483 static struct buffer_head * V2_minix_update_inode(struct inode * inode) 484 { 485 struct buffer_head * bh; 486 struct minix2_inode * raw_inode; 487 struct minix_inode_info *minix_inode = minix_i(inode); 488 int i; 489 490 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 491 if (!raw_inode) 492 return NULL; 493 raw_inode->i_mode = inode->i_mode; 494 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 495 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 496 raw_inode->i_nlinks = inode->i_nlink; 497 raw_inode->i_size = inode->i_size; 498 raw_inode->i_mtime = inode->i_mtime.tv_sec; 499 raw_inode->i_atime = inode->i_atime.tv_sec; 500 raw_inode->i_ctime = inode->i_ctime.tv_sec; 501 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 502 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 503 else for (i = 0; i < 10; i++) 504 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 505 mark_buffer_dirty(bh); 506 return bh; 507 } 508 509 static struct buffer_head *minix_update_inode(struct inode *inode) 510 { 511 if (INODE_VERSION(inode) == MINIX_V1) 512 return V1_minix_update_inode(inode); 513 else 514 return V2_minix_update_inode(inode); 515 } 516 517 static int minix_write_inode(struct inode * inode, int wait) 518 { 519 brelse(minix_update_inode(inode)); 520 return 0; 521 } 522 523 int minix_sync_inode(struct inode * inode) 524 { 525 int err = 0; 526 struct buffer_head *bh; 527 528 bh = minix_update_inode(inode); 529 if (bh && buffer_dirty(bh)) 530 { 531 sync_dirty_buffer(bh); 532 if (buffer_req(bh) && !buffer_uptodate(bh)) 533 { 534 printk("IO error syncing minix inode [%s:%08lx]\n", 535 inode->i_sb->s_id, inode->i_ino); 536 err = -1; 537 } 538 } 539 else if (!bh) 540 err = -1; 541 brelse (bh); 542 return err; 543 } 544 545 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 546 { 547 generic_fillattr(dentry->d_inode, stat); 548 if (INODE_VERSION(dentry->d_inode) == MINIX_V1) 549 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size); 550 else 551 stat->blocks = (BLOCK_SIZE / 512) * V2_minix_blocks(stat->size); 552 stat->blksize = BLOCK_SIZE; 553 return 0; 554 } 555 556 /* 557 * The function that is called for file truncation. 558 */ 559 void minix_truncate(struct inode * inode) 560 { 561 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 562 return; 563 if (INODE_VERSION(inode) == MINIX_V1) 564 V1_minix_truncate(inode); 565 else 566 V2_minix_truncate(inode); 567 } 568 569 static int minix_get_sb(struct file_system_type *fs_type, 570 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 571 { 572 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super, 573 mnt); 574 } 575 576 static struct file_system_type minix_fs_type = { 577 .owner = THIS_MODULE, 578 .name = "minix", 579 .get_sb = minix_get_sb, 580 .kill_sb = kill_block_super, 581 .fs_flags = FS_REQUIRES_DEV, 582 }; 583 584 static int __init init_minix_fs(void) 585 { 586 int err = init_inodecache(); 587 if (err) 588 goto out1; 589 err = register_filesystem(&minix_fs_type); 590 if (err) 591 goto out; 592 return 0; 593 out: 594 destroy_inodecache(); 595 out1: 596 return err; 597 } 598 599 static void __exit exit_minix_fs(void) 600 { 601 unregister_filesystem(&minix_fs_type); 602 destroy_inodecache(); 603 } 604 605 module_init(init_minix_fs) 606 module_exit(exit_minix_fs) 607 MODULE_LICENSE("GPL"); 608 609