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 * Updated to filesystem version 3 by Daniel Aragones 11 */ 12 13 #include <linux/module.h> 14 #include "minix.h" 15 #include <linux/buffer_head.h> 16 #include <linux/slab.h> 17 #include <linux/init.h> 18 #include <linux/highuid.h> 19 #include <linux/vfs.h> 20 21 static void minix_read_inode(struct inode * inode); 22 static int minix_write_inode(struct inode * inode, int wait); 23 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf); 24 static int minix_remount (struct super_block * sb, int * flags, char * data); 25 26 static void minix_delete_inode(struct inode *inode) 27 { 28 truncate_inode_pages(&inode->i_data, 0); 29 inode->i_size = 0; 30 minix_truncate(inode); 31 minix_free_inode(inode); 32 } 33 34 static void minix_put_super(struct super_block *sb) 35 { 36 int i; 37 struct minix_sb_info *sbi = minix_sb(sb); 38 39 if (!(sb->s_flags & MS_RDONLY)) { 40 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */ 41 sbi->s_ms->s_state = sbi->s_mount_state; 42 mark_buffer_dirty(sbi->s_sbh); 43 } 44 for (i = 0; i < sbi->s_imap_blocks; i++) 45 brelse(sbi->s_imap[i]); 46 for (i = 0; i < sbi->s_zmap_blocks; i++) 47 brelse(sbi->s_zmap[i]); 48 brelse (sbi->s_sbh); 49 kfree(sbi->s_imap); 50 sb->s_fs_info = NULL; 51 kfree(sbi); 52 53 return; 54 } 55 56 static struct kmem_cache * minix_inode_cachep; 57 58 static struct inode *minix_alloc_inode(struct super_block *sb) 59 { 60 struct minix_inode_info *ei; 61 ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL); 62 if (!ei) 63 return NULL; 64 return &ei->vfs_inode; 65 } 66 67 static void minix_destroy_inode(struct inode *inode) 68 { 69 kmem_cache_free(minix_inode_cachep, minix_i(inode)); 70 } 71 72 static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags) 73 { 74 struct minix_inode_info *ei = (struct minix_inode_info *) foo; 75 76 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 77 SLAB_CTOR_CONSTRUCTOR) 78 inode_init_once(&ei->vfs_inode); 79 } 80 81 static int init_inodecache(void) 82 { 83 minix_inode_cachep = kmem_cache_create("minix_inode_cache", 84 sizeof(struct minix_inode_info), 85 0, (SLAB_RECLAIM_ACCOUNT| 86 SLAB_MEM_SPREAD), 87 init_once, NULL); 88 if (minix_inode_cachep == NULL) 89 return -ENOMEM; 90 return 0; 91 } 92 93 static void destroy_inodecache(void) 94 { 95 kmem_cache_destroy(minix_inode_cachep); 96 } 97 98 static const struct super_operations minix_sops = { 99 .alloc_inode = minix_alloc_inode, 100 .destroy_inode = minix_destroy_inode, 101 .read_inode = minix_read_inode, 102 .write_inode = minix_write_inode, 103 .delete_inode = minix_delete_inode, 104 .put_super = minix_put_super, 105 .statfs = minix_statfs, 106 .remount_fs = minix_remount, 107 }; 108 109 static int minix_remount (struct super_block * sb, int * flags, char * data) 110 { 111 struct minix_sb_info * sbi = minix_sb(sb); 112 struct minix_super_block * ms; 113 114 ms = sbi->s_ms; 115 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 116 return 0; 117 if (*flags & MS_RDONLY) { 118 if (ms->s_state & MINIX_VALID_FS || 119 !(sbi->s_mount_state & MINIX_VALID_FS)) 120 return 0; 121 /* Mounting a rw partition read-only. */ 122 if (sbi->s_version != MINIX_V3) 123 ms->s_state = sbi->s_mount_state; 124 mark_buffer_dirty(sbi->s_sbh); 125 } else { 126 /* Mount a partition which is read-only, read-write. */ 127 if (sbi->s_version != MINIX_V3) { 128 sbi->s_mount_state = ms->s_state; 129 ms->s_state &= ~MINIX_VALID_FS; 130 } else { 131 sbi->s_mount_state = MINIX_VALID_FS; 132 } 133 mark_buffer_dirty(sbi->s_sbh); 134 135 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 136 printk("MINIX-fs warning: remounting unchecked fs, " 137 "running fsck is recommended\n"); 138 else if ((sbi->s_mount_state & MINIX_ERROR_FS)) 139 printk("MINIX-fs warning: remounting fs with errors, " 140 "running fsck is recommended\n"); 141 } 142 return 0; 143 } 144 145 static int minix_fill_super(struct super_block *s, void *data, int silent) 146 { 147 struct buffer_head *bh; 148 struct buffer_head **map; 149 struct minix_super_block *ms; 150 struct minix3_super_block *m3s = NULL; 151 unsigned long i, block; 152 struct inode *root_inode; 153 struct minix_sb_info *sbi; 154 155 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL); 156 if (!sbi) 157 return -ENOMEM; 158 s->s_fs_info = sbi; 159 160 BUILD_BUG_ON(32 != sizeof (struct minix_inode)); 161 BUILD_BUG_ON(64 != sizeof(struct minix2_inode)); 162 163 if (!sb_set_blocksize(s, BLOCK_SIZE)) 164 goto out_bad_hblock; 165 166 if (!(bh = sb_bread(s, 1))) 167 goto out_bad_sb; 168 169 ms = (struct minix_super_block *) bh->b_data; 170 sbi->s_ms = ms; 171 sbi->s_sbh = bh; 172 sbi->s_mount_state = ms->s_state; 173 sbi->s_ninodes = ms->s_ninodes; 174 sbi->s_nzones = ms->s_nzones; 175 sbi->s_imap_blocks = ms->s_imap_blocks; 176 sbi->s_zmap_blocks = ms->s_zmap_blocks; 177 sbi->s_firstdatazone = ms->s_firstdatazone; 178 sbi->s_log_zone_size = ms->s_log_zone_size; 179 sbi->s_max_size = ms->s_max_size; 180 s->s_magic = ms->s_magic; 181 if (s->s_magic == MINIX_SUPER_MAGIC) { 182 sbi->s_version = MINIX_V1; 183 sbi->s_dirsize = 16; 184 sbi->s_namelen = 14; 185 sbi->s_link_max = MINIX_LINK_MAX; 186 } else if (s->s_magic == MINIX_SUPER_MAGIC2) { 187 sbi->s_version = MINIX_V1; 188 sbi->s_dirsize = 32; 189 sbi->s_namelen = 30; 190 sbi->s_link_max = MINIX_LINK_MAX; 191 } else if (s->s_magic == MINIX2_SUPER_MAGIC) { 192 sbi->s_version = MINIX_V2; 193 sbi->s_nzones = ms->s_zones; 194 sbi->s_dirsize = 16; 195 sbi->s_namelen = 14; 196 sbi->s_link_max = MINIX2_LINK_MAX; 197 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { 198 sbi->s_version = MINIX_V2; 199 sbi->s_nzones = ms->s_zones; 200 sbi->s_dirsize = 32; 201 sbi->s_namelen = 30; 202 sbi->s_link_max = MINIX2_LINK_MAX; 203 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) { 204 m3s = (struct minix3_super_block *) bh->b_data; 205 s->s_magic = m3s->s_magic; 206 sbi->s_imap_blocks = m3s->s_imap_blocks; 207 sbi->s_zmap_blocks = m3s->s_zmap_blocks; 208 sbi->s_firstdatazone = m3s->s_firstdatazone; 209 sbi->s_log_zone_size = m3s->s_log_zone_size; 210 sbi->s_max_size = m3s->s_max_size; 211 sbi->s_ninodes = m3s->s_ninodes; 212 sbi->s_nzones = m3s->s_zones; 213 sbi->s_dirsize = 64; 214 sbi->s_namelen = 60; 215 sbi->s_version = MINIX_V3; 216 sbi->s_link_max = MINIX2_LINK_MAX; 217 sbi->s_mount_state = MINIX_VALID_FS; 218 sb_set_blocksize(s, m3s->s_blocksize); 219 } else 220 goto out_no_fs; 221 222 /* 223 * Allocate the buffer map to keep the superblock small. 224 */ 225 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0) 226 goto out_illegal_sb; 227 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 228 map = kzalloc(i, GFP_KERNEL); 229 if (!map) 230 goto out_no_map; 231 sbi->s_imap = &map[0]; 232 sbi->s_zmap = &map[sbi->s_imap_blocks]; 233 234 block=2; 235 for (i=0 ; i < sbi->s_imap_blocks ; i++) { 236 if (!(sbi->s_imap[i]=sb_bread(s, block))) 237 goto out_no_bitmap; 238 block++; 239 } 240 for (i=0 ; i < sbi->s_zmap_blocks ; i++) { 241 if (!(sbi->s_zmap[i]=sb_bread(s, block))) 242 goto out_no_bitmap; 243 block++; 244 } 245 246 minix_set_bit(0,sbi->s_imap[0]->b_data); 247 minix_set_bit(0,sbi->s_zmap[0]->b_data); 248 249 /* set up enough so that it can read an inode */ 250 s->s_op = &minix_sops; 251 root_inode = iget(s, MINIX_ROOT_INO); 252 if (!root_inode || is_bad_inode(root_inode)) 253 goto out_no_root; 254 255 s->s_root = d_alloc_root(root_inode); 256 if (!s->s_root) 257 goto out_iput; 258 259 if (!NO_TRUNCATE) 260 s->s_root->d_op = &minix_dentry_operations; 261 262 if (!(s->s_flags & MS_RDONLY)) { 263 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */ 264 ms->s_state &= ~MINIX_VALID_FS; 265 mark_buffer_dirty(bh); 266 } 267 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 268 printk("MINIX-fs: mounting unchecked file system, " 269 "running fsck is recommended\n"); 270 else if (sbi->s_mount_state & MINIX_ERROR_FS) 271 printk("MINIX-fs: mounting file system with errors, " 272 "running fsck is recommended\n"); 273 return 0; 274 275 out_iput: 276 iput(root_inode); 277 goto out_freemap; 278 279 out_no_root: 280 if (!silent) 281 printk("MINIX-fs: get root inode failed\n"); 282 goto out_freemap; 283 284 out_no_bitmap: 285 printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); 286 out_freemap: 287 for (i = 0; i < sbi->s_imap_blocks; i++) 288 brelse(sbi->s_imap[i]); 289 for (i = 0; i < sbi->s_zmap_blocks; i++) 290 brelse(sbi->s_zmap[i]); 291 kfree(sbi->s_imap); 292 goto out_release; 293 294 out_no_map: 295 if (!silent) 296 printk("MINIX-fs: can't allocate map\n"); 297 goto out_release; 298 299 out_illegal_sb: 300 if (!silent) 301 printk("MINIX-fs: bad superblock\n"); 302 goto out_release; 303 304 out_no_fs: 305 if (!silent) 306 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 " 307 "on device %s.\n", s->s_id); 308 out_release: 309 brelse(bh); 310 goto out; 311 312 out_bad_hblock: 313 printk("MINIX-fs: blocksize too small for device\n"); 314 goto out; 315 316 out_bad_sb: 317 printk("MINIX-fs: unable to read superblock\n"); 318 out: 319 s->s_fs_info = NULL; 320 kfree(sbi); 321 return -EINVAL; 322 } 323 324 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf) 325 { 326 struct minix_sb_info *sbi = minix_sb(dentry->d_sb); 327 buf->f_type = dentry->d_sb->s_magic; 328 buf->f_bsize = dentry->d_sb->s_blocksize; 329 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; 330 buf->f_bfree = minix_count_free_blocks(sbi); 331 buf->f_bavail = buf->f_bfree; 332 buf->f_files = sbi->s_ninodes; 333 buf->f_ffree = minix_count_free_inodes(sbi); 334 buf->f_namelen = sbi->s_namelen; 335 return 0; 336 } 337 338 static int minix_get_block(struct inode *inode, sector_t block, 339 struct buffer_head *bh_result, int create) 340 { 341 if (INODE_VERSION(inode) == MINIX_V1) 342 return V1_minix_get_block(inode, block, bh_result, create); 343 else 344 return V2_minix_get_block(inode, block, bh_result, create); 345 } 346 347 static int minix_writepage(struct page *page, struct writeback_control *wbc) 348 { 349 return block_write_full_page(page, minix_get_block, wbc); 350 } 351 static int minix_readpage(struct file *file, struct page *page) 352 { 353 return block_read_full_page(page,minix_get_block); 354 } 355 static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) 356 { 357 return block_prepare_write(page,from,to,minix_get_block); 358 } 359 static sector_t minix_bmap(struct address_space *mapping, sector_t block) 360 { 361 return generic_block_bmap(mapping,block,minix_get_block); 362 } 363 static const struct address_space_operations minix_aops = { 364 .readpage = minix_readpage, 365 .writepage = minix_writepage, 366 .sync_page = block_sync_page, 367 .prepare_write = minix_prepare_write, 368 .commit_write = generic_commit_write, 369 .bmap = minix_bmap 370 }; 371 372 static const struct inode_operations minix_symlink_inode_operations = { 373 .readlink = generic_readlink, 374 .follow_link = page_follow_link_light, 375 .put_link = page_put_link, 376 .getattr = minix_getattr, 377 }; 378 379 void minix_set_inode(struct inode *inode, dev_t rdev) 380 { 381 if (S_ISREG(inode->i_mode)) { 382 inode->i_op = &minix_file_inode_operations; 383 inode->i_fop = &minix_file_operations; 384 inode->i_mapping->a_ops = &minix_aops; 385 } else if (S_ISDIR(inode->i_mode)) { 386 inode->i_op = &minix_dir_inode_operations; 387 inode->i_fop = &minix_dir_operations; 388 inode->i_mapping->a_ops = &minix_aops; 389 } else if (S_ISLNK(inode->i_mode)) { 390 inode->i_op = &minix_symlink_inode_operations; 391 inode->i_mapping->a_ops = &minix_aops; 392 } else 393 init_special_inode(inode, inode->i_mode, rdev); 394 } 395 396 /* 397 * The minix V1 function to read an inode. 398 */ 399 static void V1_minix_read_inode(struct inode * inode) 400 { 401 struct buffer_head * bh; 402 struct minix_inode * raw_inode; 403 struct minix_inode_info *minix_inode = minix_i(inode); 404 int i; 405 406 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 407 if (!raw_inode) { 408 make_bad_inode(inode); 409 return; 410 } 411 inode->i_mode = raw_inode->i_mode; 412 inode->i_uid = (uid_t)raw_inode->i_uid; 413 inode->i_gid = (gid_t)raw_inode->i_gid; 414 inode->i_nlink = raw_inode->i_nlinks; 415 inode->i_size = raw_inode->i_size; 416 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; 417 inode->i_mtime.tv_nsec = 0; 418 inode->i_atime.tv_nsec = 0; 419 inode->i_ctime.tv_nsec = 0; 420 inode->i_blocks = 0; 421 for (i = 0; i < 9; i++) 422 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 423 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 424 brelse(bh); 425 } 426 427 /* 428 * The minix V2 function to read an inode. 429 */ 430 static void V2_minix_read_inode(struct inode * inode) 431 { 432 struct buffer_head * bh; 433 struct minix2_inode * raw_inode; 434 struct minix_inode_info *minix_inode = minix_i(inode); 435 int i; 436 437 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 438 if (!raw_inode) { 439 make_bad_inode(inode); 440 return; 441 } 442 inode->i_mode = raw_inode->i_mode; 443 inode->i_uid = (uid_t)raw_inode->i_uid; 444 inode->i_gid = (gid_t)raw_inode->i_gid; 445 inode->i_nlink = raw_inode->i_nlinks; 446 inode->i_size = raw_inode->i_size; 447 inode->i_mtime.tv_sec = raw_inode->i_mtime; 448 inode->i_atime.tv_sec = raw_inode->i_atime; 449 inode->i_ctime.tv_sec = raw_inode->i_ctime; 450 inode->i_mtime.tv_nsec = 0; 451 inode->i_atime.tv_nsec = 0; 452 inode->i_ctime.tv_nsec = 0; 453 inode->i_blocks = 0; 454 for (i = 0; i < 10; i++) 455 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 456 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 457 brelse(bh); 458 } 459 460 /* 461 * The global function to read an inode. 462 */ 463 static void minix_read_inode(struct inode * inode) 464 { 465 if (INODE_VERSION(inode) == MINIX_V1) 466 V1_minix_read_inode(inode); 467 else 468 V2_minix_read_inode(inode); 469 } 470 471 /* 472 * The minix V1 function to synchronize an inode. 473 */ 474 static struct buffer_head * V1_minix_update_inode(struct inode * inode) 475 { 476 struct buffer_head * bh; 477 struct minix_inode * raw_inode; 478 struct minix_inode_info *minix_inode = minix_i(inode); 479 int i; 480 481 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 482 if (!raw_inode) 483 return NULL; 484 raw_inode->i_mode = inode->i_mode; 485 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 486 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 487 raw_inode->i_nlinks = inode->i_nlink; 488 raw_inode->i_size = inode->i_size; 489 raw_inode->i_time = inode->i_mtime.tv_sec; 490 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 491 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 492 else for (i = 0; i < 9; i++) 493 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 494 mark_buffer_dirty(bh); 495 return bh; 496 } 497 498 /* 499 * The minix V2 function to synchronize an inode. 500 */ 501 static struct buffer_head * V2_minix_update_inode(struct inode * inode) 502 { 503 struct buffer_head * bh; 504 struct minix2_inode * raw_inode; 505 struct minix_inode_info *minix_inode = minix_i(inode); 506 int i; 507 508 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 509 if (!raw_inode) 510 return NULL; 511 raw_inode->i_mode = inode->i_mode; 512 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 513 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 514 raw_inode->i_nlinks = inode->i_nlink; 515 raw_inode->i_size = inode->i_size; 516 raw_inode->i_mtime = inode->i_mtime.tv_sec; 517 raw_inode->i_atime = inode->i_atime.tv_sec; 518 raw_inode->i_ctime = inode->i_ctime.tv_sec; 519 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 520 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 521 else for (i = 0; i < 10; i++) 522 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 523 mark_buffer_dirty(bh); 524 return bh; 525 } 526 527 static struct buffer_head *minix_update_inode(struct inode *inode) 528 { 529 if (INODE_VERSION(inode) == MINIX_V1) 530 return V1_minix_update_inode(inode); 531 else 532 return V2_minix_update_inode(inode); 533 } 534 535 static int minix_write_inode(struct inode * inode, int wait) 536 { 537 brelse(minix_update_inode(inode)); 538 return 0; 539 } 540 541 int minix_sync_inode(struct inode * inode) 542 { 543 int err = 0; 544 struct buffer_head *bh; 545 546 bh = minix_update_inode(inode); 547 if (bh && buffer_dirty(bh)) 548 { 549 sync_dirty_buffer(bh); 550 if (buffer_req(bh) && !buffer_uptodate(bh)) 551 { 552 printk("IO error syncing minix inode [%s:%08lx]\n", 553 inode->i_sb->s_id, inode->i_ino); 554 err = -1; 555 } 556 } 557 else if (!bh) 558 err = -1; 559 brelse (bh); 560 return err; 561 } 562 563 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 564 { 565 struct inode *dir = dentry->d_parent->d_inode; 566 struct super_block *sb = dir->i_sb; 567 generic_fillattr(dentry->d_inode, stat); 568 if (INODE_VERSION(dentry->d_inode) == MINIX_V1) 569 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb); 570 else 571 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb); 572 stat->blksize = sb->s_blocksize; 573 return 0; 574 } 575 576 /* 577 * The function that is called for file truncation. 578 */ 579 void minix_truncate(struct inode * inode) 580 { 581 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 582 return; 583 if (INODE_VERSION(inode) == MINIX_V1) 584 V1_minix_truncate(inode); 585 else 586 V2_minix_truncate(inode); 587 } 588 589 static int minix_get_sb(struct file_system_type *fs_type, 590 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 591 { 592 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super, 593 mnt); 594 } 595 596 static struct file_system_type minix_fs_type = { 597 .owner = THIS_MODULE, 598 .name = "minix", 599 .get_sb = minix_get_sb, 600 .kill_sb = kill_block_super, 601 .fs_flags = FS_REQUIRES_DEV, 602 }; 603 604 static int __init init_minix_fs(void) 605 { 606 int err = init_inodecache(); 607 if (err) 608 goto out1; 609 err = register_filesystem(&minix_fs_type); 610 if (err) 611 goto out; 612 return 0; 613 out: 614 destroy_inodecache(); 615 out1: 616 return err; 617 } 618 619 static void __exit exit_minix_fs(void) 620 { 621 unregister_filesystem(&minix_fs_type); 622 destroy_inodecache(); 623 } 624 625 module_init(init_minix_fs) 626 module_exit(exit_minix_fs) 627 MODULE_LICENSE("GPL"); 628 629