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inode.c
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linux-6.19.14/fs/minix/inode.c
1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * linux/fs/minix/inode.c 4 * 5 * Copyright (C) 1991, 1992 Linus Torvalds 6 * 7 * Copyright (C) 1996 Gertjan van Wingerde 8 * Minix V2 fs support. 9 * 10 * Modified for 680x0 by Andreas Schwab 11 * Updated to filesystem version 3 by Daniel Aragones 12 */ 13 14#include <linux/module.h> 15#include "minix.h" 16#include <linux/buffer_head.h> 17#include <linux/slab.h> 18#include <linux/init.h> 19#include <linux/highuid.h> 20#include <linux/mpage.h> 21#include <linux/vfs.h> 22#include <linux/writeback.h> 23#include <linux/fs_context.h> 24 25static int minix_write_inode(struct inode *inode, 26 struct writeback_control *wbc); 27static int minix_statfs(struct dentry *dentry, struct kstatfs *buf); 28 29void __minix_error_inode(struct inode *inode, const char *function, 30 unsigned int line, const char *fmt, ...) 31{ 32 struct va_format vaf; 33 va_list args; 34 35 va_start(args, fmt); 36 vaf.fmt = fmt; 37 vaf.va = &args; 38 printk(KERN_CRIT "minix-fs error (device %s): %s:%d: " 39 "inode #%lu: comm %s: %pV\n", 40 inode->i_sb->s_id, function, line, inode->i_ino, 41 current->comm, &vaf); 42 va_end(args); 43} 44 45static void minix_evict_inode(struct inode *inode) 46{ 47 truncate_inode_pages_final(&inode->i_data); 48 if (!inode->i_nlink) { 49 inode->i_size = 0; 50 minix_truncate(inode); 51 } 52 invalidate_inode_buffers(inode); 53 clear_inode(inode); 54 if (!inode->i_nlink) 55 minix_free_inode(inode); 56} 57 58static void minix_put_super(struct super_block *sb) 59{ 60 int i; 61 struct minix_sb_info *sbi = minix_sb(sb); 62 63 if (!sb_rdonly(sb)) { 64 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */ 65 sbi->s_ms->s_state = sbi->s_mount_state; 66 mark_buffer_dirty(sbi->s_sbh); 67 } 68 for (i = 0; i < sbi->s_imap_blocks; i++) 69 brelse(sbi->s_imap[i]); 70 for (i = 0; i < sbi->s_zmap_blocks; i++) 71 brelse(sbi->s_zmap[i]); 72 brelse (sbi->s_sbh); 73 kfree(sbi->s_imap); 74 sb->s_fs_info = NULL; 75 kfree(sbi); 76} 77 78static struct kmem_cache * minix_inode_cachep; 79 80static struct inode *minix_alloc_inode(struct super_block *sb) 81{ 82 struct minix_inode_info *ei; 83 ei = alloc_inode_sb(sb, minix_inode_cachep, GFP_KERNEL); 84 if (!ei) 85 return NULL; 86 return &ei->vfs_inode; 87} 88 89static void minix_free_in_core_inode(struct inode *inode) 90{ 91 kmem_cache_free(minix_inode_cachep, minix_i(inode)); 92} 93 94static void init_once(void *foo) 95{ 96 struct minix_inode_info *ei = (struct minix_inode_info *) foo; 97 98 inode_init_once(&ei->vfs_inode); 99} 100 101static int __init init_inodecache(void) 102{ 103 minix_inode_cachep = kmem_cache_create("minix_inode_cache", 104 sizeof(struct minix_inode_info), 105 0, (SLAB_RECLAIM_ACCOUNT| 106 SLAB_ACCOUNT), 107 init_once); 108 if (minix_inode_cachep == NULL) 109 return -ENOMEM; 110 return 0; 111} 112 113static void destroy_inodecache(void) 114{ 115 /* 116 * Make sure all delayed rcu free inodes are flushed before we 117 * destroy cache. 118 */ 119 rcu_barrier(); 120 kmem_cache_destroy(minix_inode_cachep); 121} 122 123static const struct super_operations minix_sops = { 124 .alloc_inode = minix_alloc_inode, 125 .free_inode = minix_free_in_core_inode, 126 .write_inode = minix_write_inode, 127 .evict_inode = minix_evict_inode, 128 .put_super = minix_put_super, 129 .statfs = minix_statfs, 130}; 131 132static int minix_reconfigure(struct fs_context *fc) 133{ 134 struct minix_super_block * ms; 135 struct super_block *sb = fc->root->d_sb; 136 struct minix_sb_info * sbi = sb->s_fs_info; 137 138 sync_filesystem(sb); 139 ms = sbi->s_ms; 140 if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb)) 141 return 0; 142 if (fc->sb_flags & SB_RDONLY) { 143 if (ms->s_state & MINIX_VALID_FS || 144 !(sbi->s_mount_state & MINIX_VALID_FS)) 145 return 0; 146 /* Mounting a rw partition read-only. */ 147 if (sbi->s_version != MINIX_V3) 148 ms->s_state = sbi->s_mount_state; 149 mark_buffer_dirty(sbi->s_sbh); 150 } else { 151 /* Mount a partition which is read-only, read-write. */ 152 if (sbi->s_version != MINIX_V3) { 153 sbi->s_mount_state = ms->s_state; 154 ms->s_state &= ~MINIX_VALID_FS; 155 } else { 156 sbi->s_mount_state = MINIX_VALID_FS; 157 } 158 mark_buffer_dirty(sbi->s_sbh); 159 160 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 161 printk("MINIX-fs warning: remounting unchecked fs, " 162 "running fsck is recommended\n"); 163 else if ((sbi->s_mount_state & MINIX_ERROR_FS)) 164 printk("MINIX-fs warning: remounting fs with errors, " 165 "running fsck is recommended\n"); 166 } 167 return 0; 168} 169 170static bool minix_check_superblock(struct super_block *sb) 171{ 172 struct minix_sb_info *sbi = minix_sb(sb); 173 unsigned long block; 174 175 if (sbi->s_log_zone_size != 0) { 176 printk("minix-fs error: zone size must equal block size. " 177 "s_log_zone_size > 0 is not supported.\n"); 178 return false; 179 } 180 181 if (sbi->s_ninodes < 1 || sbi->s_firstdatazone <= 4 || 182 sbi->s_firstdatazone >= sbi->s_nzones) 183 return false; 184 185 /* Apparently minix can create filesystems that allocate more blocks for 186 * the bitmaps than needed. We simply ignore that, but verify it didn't 187 * create one with not enough blocks and bail out if so. 188 */ 189 block = minix_blocks_needed(sbi->s_ninodes, sb->s_blocksize); 190 if (sbi->s_imap_blocks < block) { 191 printk("MINIX-fs: file system does not have enough " 192 "imap blocks allocated. Refusing to mount.\n"); 193 return false; 194 } 195 196 block = minix_blocks_needed( 197 (sbi->s_nzones - sbi->s_firstdatazone + 1), 198 sb->s_blocksize); 199 if (sbi->s_zmap_blocks < block) { 200 printk("MINIX-fs: file system does not have enough " 201 "zmap blocks allocated. Refusing to mount.\n"); 202 return false; 203 } 204 205 /* 206 * s_max_size must not exceed the block mapping limitation. This check 207 * is only needed for V1 filesystems, since V2/V3 support an extra level 208 * of indirect blocks which places the limit well above U32_MAX. 209 */ 210 if (sbi->s_version == MINIX_V1 && 211 sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE) 212 return false; 213 214 return true; 215} 216 217static int minix_fill_super(struct super_block *s, struct fs_context *fc) 218{ 219 struct buffer_head *bh; 220 struct buffer_head **map; 221 struct minix_super_block *ms; 222 struct minix3_super_block *m3s = NULL; 223 unsigned long i, block; 224 struct inode *root_inode; 225 struct minix_sb_info *sbi; 226 int ret = -EINVAL; 227 int silent = fc->sb_flags & SB_SILENT; 228 229 sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL); 230 if (!sbi) 231 return -ENOMEM; 232 s->s_fs_info = sbi; 233 234 BUILD_BUG_ON(32 != sizeof (struct minix_inode)); 235 BUILD_BUG_ON(64 != sizeof(struct minix2_inode)); 236 237 if (!sb_set_blocksize(s, BLOCK_SIZE)) 238 goto out_bad_hblock; 239 240 if (!(bh = sb_bread(s, 1))) 241 goto out_bad_sb; 242 243 ms = (struct minix_super_block *) bh->b_data; 244 sbi->s_ms = ms; 245 sbi->s_sbh = bh; 246 sbi->s_mount_state = ms->s_state; 247 sbi->s_ninodes = ms->s_ninodes; 248 sbi->s_nzones = ms->s_nzones; 249 sbi->s_imap_blocks = ms->s_imap_blocks; 250 sbi->s_zmap_blocks = ms->s_zmap_blocks; 251 sbi->s_firstdatazone = ms->s_firstdatazone; 252 sbi->s_log_zone_size = ms->s_log_zone_size; 253 s->s_maxbytes = ms->s_max_size; 254 s->s_magic = ms->s_magic; 255 if (s->s_magic == MINIX_SUPER_MAGIC) { 256 sbi->s_version = MINIX_V1; 257 sbi->s_dirsize = 16; 258 sbi->s_namelen = 14; 259 s->s_max_links = MINIX_LINK_MAX; 260 } else if (s->s_magic == MINIX_SUPER_MAGIC2) { 261 sbi->s_version = MINIX_V1; 262 sbi->s_dirsize = 32; 263 sbi->s_namelen = 30; 264 s->s_max_links = MINIX_LINK_MAX; 265 } else if (s->s_magic == MINIX2_SUPER_MAGIC) { 266 sbi->s_version = MINIX_V2; 267 sbi->s_nzones = ms->s_zones; 268 sbi->s_dirsize = 16; 269 sbi->s_namelen = 14; 270 s->s_max_links = MINIX2_LINK_MAX; 271 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { 272 sbi->s_version = MINIX_V2; 273 sbi->s_nzones = ms->s_zones; 274 sbi->s_dirsize = 32; 275 sbi->s_namelen = 30; 276 s->s_max_links = MINIX2_LINK_MAX; 277 } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) { 278 m3s = (struct minix3_super_block *) bh->b_data; 279 s->s_magic = m3s->s_magic; 280 sbi->s_imap_blocks = m3s->s_imap_blocks; 281 sbi->s_zmap_blocks = m3s->s_zmap_blocks; 282 sbi->s_firstdatazone = m3s->s_firstdatazone; 283 sbi->s_log_zone_size = m3s->s_log_zone_size; 284 s->s_maxbytes = m3s->s_max_size; 285 sbi->s_ninodes = m3s->s_ninodes; 286 sbi->s_nzones = m3s->s_zones; 287 sbi->s_dirsize = 64; 288 sbi->s_namelen = 60; 289 sbi->s_version = MINIX_V3; 290 sbi->s_mount_state = MINIX_VALID_FS; 291 sb_set_blocksize(s, m3s->s_blocksize); 292 s->s_max_links = MINIX2_LINK_MAX; 293 } else 294 goto out_no_fs; 295 296 if (!minix_check_superblock(s)) 297 goto out_illegal_sb; 298 299 /* 300 * Allocate the buffer map to keep the superblock small. 301 */ 302 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 303 map = kzalloc(i, GFP_KERNEL); 304 if (!map) 305 goto out_no_map; 306 sbi->s_imap = &map[0]; 307 sbi->s_zmap = &map[sbi->s_imap_blocks]; 308 309 block=2; 310 for (i=0 ; i < sbi->s_imap_blocks ; i++) { 311 if (!(sbi->s_imap[i]=sb_bread(s, block))) 312 goto out_no_bitmap; 313 block++; 314 } 315 for (i=0 ; i < sbi->s_zmap_blocks ; i++) { 316 if (!(sbi->s_zmap[i]=sb_bread(s, block))) 317 goto out_no_bitmap; 318 block++; 319 } 320 321 minix_set_bit(0,sbi->s_imap[0]->b_data); 322 minix_set_bit(0,sbi->s_zmap[0]->b_data); 323 324 /* set up enough so that it can read an inode */ 325 s->s_op = &minix_sops; 326 s->s_time_min = 0; 327 s->s_time_max = U32_MAX; 328 root_inode = minix_iget(s, MINIX_ROOT_INO); 329 if (IS_ERR(root_inode)) { 330 ret = PTR_ERR(root_inode); 331 goto out_no_root; 332 } 333 334 ret = -ENOMEM; 335 s->s_root = d_make_root(root_inode); 336 if (!s->s_root) 337 goto out_no_root; 338 339 if (!sb_rdonly(s)) { 340 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */ 341 ms->s_state &= ~MINIX_VALID_FS; 342 mark_buffer_dirty(bh); 343 } 344 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 345 printk("MINIX-fs: mounting unchecked file system, " 346 "running fsck is recommended\n"); 347 else if (sbi->s_mount_state & MINIX_ERROR_FS) 348 printk("MINIX-fs: mounting file system with errors, " 349 "running fsck is recommended\n"); 350 351 return 0; 352 353out_no_root: 354 if (!silent) 355 printk("MINIX-fs: get root inode failed\n"); 356 goto out_freemap; 357 358out_no_bitmap: 359 printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); 360out_freemap: 361 for (i = 0; i < sbi->s_imap_blocks; i++) 362 brelse(sbi->s_imap[i]); 363 for (i = 0; i < sbi->s_zmap_blocks; i++) 364 brelse(sbi->s_zmap[i]); 365 kfree(sbi->s_imap); 366 goto out_release; 367 368out_no_map: 369 ret = -ENOMEM; 370 if (!silent) 371 printk("MINIX-fs: can't allocate map\n"); 372 goto out_release; 373 374out_illegal_sb: 375 if (!silent) 376 printk("MINIX-fs: bad superblock\n"); 377 goto out_release; 378 379out_no_fs: 380 if (!silent) 381 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 " 382 "on device %s.\n", s->s_id); 383out_release: 384 brelse(bh); 385 goto out; 386 387out_bad_hblock: 388 printk("MINIX-fs: blocksize too small for device\n"); 389 goto out; 390 391out_bad_sb: 392 printk("MINIX-fs: unable to read superblock\n"); 393out: 394 s->s_fs_info = NULL; 395 kfree(sbi); 396 return ret; 397} 398 399static int minix_get_tree(struct fs_context *fc) 400{ 401 return get_tree_bdev(fc, minix_fill_super); 402} 403 404static const struct fs_context_operations minix_context_ops = { 405 .get_tree = minix_get_tree, 406 .reconfigure = minix_reconfigure, 407}; 408 409static int minix_init_fs_context(struct fs_context *fc) 410{ 411 fc->ops = &minix_context_ops; 412 413 return 0; 414} 415 416static int minix_statfs(struct dentry *dentry, struct kstatfs *buf) 417{ 418 struct super_block *sb = dentry->d_sb; 419 struct minix_sb_info *sbi = minix_sb(sb); 420 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 421 buf->f_type = sb->s_magic; 422 buf->f_bsize = sb->s_blocksize; 423 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; 424 buf->f_bfree = minix_count_free_blocks(sb); 425 buf->f_bavail = buf->f_bfree; 426 buf->f_files = sbi->s_ninodes; 427 buf->f_ffree = minix_count_free_inodes(sb); 428 buf->f_namelen = sbi->s_namelen; 429 buf->f_fsid = u64_to_fsid(id); 430 431 return 0; 432} 433 434static int minix_get_block(struct inode *inode, sector_t block, 435 struct buffer_head *bh_result, int create) 436{ 437 if (INODE_VERSION(inode) == MINIX_V1) 438 return V1_minix_get_block(inode, block, bh_result, create); 439 else 440 return V2_minix_get_block(inode, block, bh_result, create); 441} 442 443static int minix_writepages(struct address_space *mapping, 444 struct writeback_control *wbc) 445{ 446 return mpage_writepages(mapping, wbc, minix_get_block); 447} 448 449static int minix_read_folio(struct file *file, struct folio *folio) 450{ 451 return block_read_full_folio(folio, minix_get_block); 452} 453 454int minix_prepare_chunk(struct folio *folio, loff_t pos, unsigned len) 455{ 456 return __block_write_begin(folio, pos, len, minix_get_block); 457} 458 459static void minix_write_failed(struct address_space *mapping, loff_t to) 460{ 461 struct inode *inode = mapping->host; 462 463 if (to > inode->i_size) { 464 truncate_pagecache(inode, inode->i_size); 465 minix_truncate(inode); 466 } 467} 468 469static int minix_write_begin(const struct kiocb *iocb, 470 struct address_space *mapping, 471 loff_t pos, unsigned len, 472 struct folio **foliop, void **fsdata) 473{ 474 int ret; 475 476 ret = block_write_begin(mapping, pos, len, foliop, minix_get_block); 477 if (unlikely(ret)) 478 minix_write_failed(mapping, pos + len); 479 480 return ret; 481} 482 483static sector_t minix_bmap(struct address_space *mapping, sector_t block) 484{ 485 return generic_block_bmap(mapping,block,minix_get_block); 486} 487 488static const struct address_space_operations minix_aops = { 489 .dirty_folio = block_dirty_folio, 490 .invalidate_folio = block_invalidate_folio, 491 .read_folio = minix_read_folio, 492 .writepages = minix_writepages, 493 .write_begin = minix_write_begin, 494 .write_end = generic_write_end, 495 .migrate_folio = buffer_migrate_folio, 496 .bmap = minix_bmap, 497 .direct_IO = noop_direct_IO 498}; 499 500static const struct inode_operations minix_symlink_inode_operations = { 501 .get_link = page_get_link, 502 .getattr = minix_getattr, 503}; 504 505void minix_set_inode(struct inode *inode, dev_t rdev) 506{ 507 if (S_ISREG(inode->i_mode)) { 508 inode->i_op = &minix_file_inode_operations; 509 inode->i_fop = &minix_file_operations; 510 inode->i_mapping->a_ops = &minix_aops; 511 } else if (S_ISDIR(inode->i_mode)) { 512 inode->i_op = &minix_dir_inode_operations; 513 inode->i_fop = &minix_dir_operations; 514 inode->i_mapping->a_ops = &minix_aops; 515 } else if (S_ISLNK(inode->i_mode)) { 516 inode->i_op = &minix_symlink_inode_operations; 517 inode_nohighmem(inode); 518 inode->i_mapping->a_ops = &minix_aops; 519 } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || 520 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { 521 init_special_inode(inode, inode->i_mode, rdev); 522 } else { 523 printk(KERN_DEBUG "MINIX-fs: Invalid file type 0%04o for inode %lu.\n", 524 inode->i_mode, inode->i_ino); 525 make_bad_inode(inode); 526 } 527} 528 529/* 530 * The minix V1 function to read an inode. 531 */ 532static struct inode *V1_minix_iget(struct inode *inode) 533{ 534 struct buffer_head * bh; 535 struct minix_inode * raw_inode; 536 struct minix_inode_info *minix_inode = minix_i(inode); 537 int i; 538 539 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 540 if (!raw_inode) { 541 iget_failed(inode); 542 return ERR_PTR(-EIO); 543 } 544 if (raw_inode->i_nlinks == 0) { 545 printk("MINIX-fs: deleted inode referenced: %lu\n", 546 inode->i_ino); 547 brelse(bh); 548 iget_failed(inode); 549 return ERR_PTR(-ESTALE); 550 } 551 inode->i_mode = raw_inode->i_mode; 552 i_uid_write(inode, raw_inode->i_uid); 553 i_gid_write(inode, raw_inode->i_gid); 554 set_nlink(inode, raw_inode->i_nlinks); 555 inode->i_size = raw_inode->i_size; 556 inode_set_mtime_to_ts(inode, 557 inode_set_atime_to_ts(inode, inode_set_ctime(inode, raw_inode->i_time, 0))); 558 inode->i_blocks = 0; 559 for (i = 0; i < 9; i++) 560 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 561 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 562 brelse(bh); 563 unlock_new_inode(inode); 564 return inode; 565} 566 567/* 568 * The minix V2 function to read an inode. 569 */ 570static struct inode *V2_minix_iget(struct inode *inode) 571{ 572 struct buffer_head * bh; 573 struct minix2_inode * raw_inode; 574 struct minix_inode_info *minix_inode = minix_i(inode); 575 int i; 576 577 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 578 if (!raw_inode) { 579 iget_failed(inode); 580 return ERR_PTR(-EIO); 581 } 582 if (raw_inode->i_nlinks == 0) { 583 printk("MINIX-fs: deleted inode referenced: %lu\n", 584 inode->i_ino); 585 brelse(bh); 586 iget_failed(inode); 587 return ERR_PTR(-ESTALE); 588 } 589 inode->i_mode = raw_inode->i_mode; 590 i_uid_write(inode, raw_inode->i_uid); 591 i_gid_write(inode, raw_inode->i_gid); 592 set_nlink(inode, raw_inode->i_nlinks); 593 inode->i_size = raw_inode->i_size; 594 inode_set_mtime(inode, raw_inode->i_mtime, 0); 595 inode_set_atime(inode, raw_inode->i_atime, 0); 596 inode_set_ctime(inode, raw_inode->i_ctime, 0); 597 inode->i_blocks = 0; 598 for (i = 0; i < 10; i++) 599 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 600 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 601 brelse(bh); 602 unlock_new_inode(inode); 603 return inode; 604} 605 606/* 607 * The global function to read an inode. 608 */ 609struct inode *minix_iget(struct super_block *sb, unsigned long ino) 610{ 611 struct inode *inode; 612 613 inode = iget_locked(sb, ino); 614 if (!inode) 615 return ERR_PTR(-ENOMEM); 616 if (!(inode_state_read_once(inode) & I_NEW)) 617 return inode; 618 619 if (INODE_VERSION(inode) == MINIX_V1) 620 return V1_minix_iget(inode); 621 else 622 return V2_minix_iget(inode); 623} 624 625/* 626 * The minix V1 function to synchronize an inode. 627 */ 628static struct buffer_head * V1_minix_update_inode(struct inode * inode) 629{ 630 struct buffer_head * bh; 631 struct minix_inode * raw_inode; 632 struct minix_inode_info *minix_inode = minix_i(inode); 633 int i; 634 635 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 636 if (!raw_inode) 637 return NULL; 638 raw_inode->i_mode = inode->i_mode; 639 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode)); 640 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode)); 641 raw_inode->i_nlinks = inode->i_nlink; 642 raw_inode->i_size = inode->i_size; 643 raw_inode->i_time = inode_get_mtime_sec(inode); 644 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 645 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 646 else for (i = 0; i < 9; i++) 647 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 648 mark_buffer_dirty(bh); 649 return bh; 650} 651 652/* 653 * The minix V2 function to synchronize an inode. 654 */ 655static struct buffer_head * V2_minix_update_inode(struct inode * inode) 656{ 657 struct buffer_head * bh; 658 struct minix2_inode * raw_inode; 659 struct minix_inode_info *minix_inode = minix_i(inode); 660 int i; 661 662 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 663 if (!raw_inode) 664 return NULL; 665 raw_inode->i_mode = inode->i_mode; 666 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode)); 667 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode)); 668 raw_inode->i_nlinks = inode->i_nlink; 669 raw_inode->i_size = inode->i_size; 670 raw_inode->i_mtime = inode_get_mtime_sec(inode); 671 raw_inode->i_atime = inode_get_atime_sec(inode); 672 raw_inode->i_ctime = inode_get_ctime_sec(inode); 673 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 674 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 675 else for (i = 0; i < 10; i++) 676 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 677 mark_buffer_dirty(bh); 678 return bh; 679} 680 681static int minix_write_inode(struct inode *inode, struct writeback_control *wbc) 682{ 683 int err = 0; 684 struct buffer_head *bh; 685 686 if (INODE_VERSION(inode) == MINIX_V1) 687 bh = V1_minix_update_inode(inode); 688 else 689 bh = V2_minix_update_inode(inode); 690 if (!bh) 691 return -EIO; 692 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) { 693 sync_dirty_buffer(bh); 694 if (buffer_req(bh) && !buffer_uptodate(bh)) { 695 printk("IO error syncing minix inode [%s:%08lx]\n", 696 inode->i_sb->s_id, inode->i_ino); 697 err = -EIO; 698 } 699 } 700 brelse (bh); 701 return err; 702} 703 704int minix_getattr(struct mnt_idmap *idmap, const struct path *path, 705 struct kstat *stat, u32 request_mask, unsigned int flags) 706{ 707 struct super_block *sb = path->dentry->d_sb; 708 struct inode *inode = d_inode(path->dentry); 709 710 generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat); 711 if (INODE_VERSION(inode) == MINIX_V1) 712 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb); 713 else 714 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb); 715 stat->blksize = sb->s_blocksize; 716 return 0; 717} 718 719/* 720 * The function that is called for file truncation. 721 */ 722void minix_truncate(struct inode * inode) 723{ 724 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 725 return; 726 if (INODE_VERSION(inode) == MINIX_V1) 727 V1_minix_truncate(inode); 728 else 729 V2_minix_truncate(inode); 730} 731 732static struct file_system_type minix_fs_type = { 733 .owner = THIS_MODULE, 734 .name = "minix", 735 .kill_sb = kill_block_super, 736 .fs_flags = FS_REQUIRES_DEV, 737 .init_fs_context = minix_init_fs_context, 738}; 739MODULE_ALIAS_FS("minix"); 740 741static int __init init_minix_fs(void) 742{ 743 int err = init_inodecache(); 744 if (err) 745 goto out1; 746 err = register_filesystem(&minix_fs_type); 747 if (err) 748 goto out; 749 return 0; 750out: 751 destroy_inodecache(); 752out1: 753 return err; 754} 755 756static void __exit exit_minix_fs(void) 757{ 758 unregister_filesystem(&minix_fs_type); 759 destroy_inodecache(); 760} 761 762module_init(init_minix_fs) 763module_exit(exit_minix_fs) 764MODULE_DESCRIPTION("Minix file system"); 765MODULE_LICENSE("GPL"); 766
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