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