fs/ufs/truncate.c

   1 /*
   2  *  linux/fs/ufs/truncate.c
   3  *
   4  * Copyright (C) 1998
   5  * Daniel Pirkl <daniel.pirkl@email.cz>
   6  * Charles University, Faculty of Mathematics and Physics
   7  *
   8  *  from
   9  *
  10  *  linux/fs/ext2/truncate.c
  11  *
  12  * Copyright (C) 1992, 1993, 1994, 1995
  13  * Remy Card (card@masi.ibp.fr)
  14  * Laboratoire MASI - Institut Blaise Pascal
  15  * Universite Pierre et Marie Curie (Paris VI)
  16  *
  17  *  from
  18  *
  19  *  linux/fs/minix/truncate.c
  20  *
  21  *  Copyright (C) 1991, 1992  Linus Torvalds
  22  *
  23  *  Big-endian to little-endian byte-swapping/bitmaps by
  24  *        David S. Miller (davem@caip.rutgers.edu), 1995
  25  */
  26
  27 /*
  28  * Real random numbers for secure rm added 94/02/18
  29  * Idea from Pierre del Perugia <delperug@gla.ecoledoc.ibp.fr>
  30  */
  31
  32 /*
  33  * Adoptation to use page cache and UFS2 write support by
  34  * Evgeniy Dushistov <dushistov@mail.ru>, 2006-2007
  35  */
  36
  37 #include <linux/errno.h>
  38 #include <linux/fs.h>
  39 #include <linux/fcntl.h>
  40 #include <linux/time.h>
  41 #include <linux/stat.h>
  42 #include <linux/string.h>
  43 #include <linux/buffer_head.h>
  44 #include <linux/blkdev.h>
  45 #include <linux/sched.h>
  46
  47 #include "ufs_fs.h"
  48 #include "ufs.h"
  49 #include "swab.h"
  50 #include "util.h"
  51
  52 /*
  53  * Secure deletion currently doesn't work. It interacts very badly
  54  * with buffers shared with memory mappings, and for that reason
  55  * can't be done in the truncate() routines. It should instead be
  56  * done separately in "release()" before calling the truncate routines
  57  * that will release the actual file blocks.
  58  *
  59  *              Linus
  60  */
  61
  62 #define DIRECT_BLOCK ((inode->i_size + uspi->s_bsize - 1) >> uspi->s_bshift)
  63 #define DIRECT_FRAGMENT ((inode->i_size + uspi->s_fsize - 1) >> uspi->s_fshift)
  64
  65
  66 static int ufs_trunc_direct(struct inode *inode)
  67 {
  68         struct ufs_inode_info *ufsi = UFS_I(inode);
  69         struct super_block * sb;
  70         struct ufs_sb_private_info * uspi;
  71         void *p;
  72         u64 frag1, frag2, frag3, frag4, block1, block2;
  73         unsigned frag_to_free, free_count;
  74         unsigned i, tmp;
  75         int retry;
  76
  77         UFSD("ENTER: ino %lu\n", inode->i_ino);
  78
  79         sb = inode->i_sb;
  80         uspi = UFS_SB(sb)->s_uspi;
  81
  82         frag_to_free = 0;
  83         free_count = 0;
  84         retry = 0;
  85
  86         frag1 = DIRECT_FRAGMENT;
  87         frag4 = min_t(u32, UFS_NDIR_FRAGMENT, ufsi->i_lastfrag);
  88         frag2 = ((frag1 & uspi->s_fpbmask) ? ((frag1 | uspi->s_fpbmask) + 1) : frag1);
  89         frag3 = frag4 & ~uspi->s_fpbmask;
  90         block1 = block2 = 0;
  91         if (frag2 > frag3) {
  92                 frag2 = frag4;
  93                 frag3 = frag4 = 0;
  94         } else if (frag2 < frag3) {
  95                 block1 = ufs_fragstoblks (frag2);
  96                 block2 = ufs_fragstoblks (frag3);
  97         }
  98
  99         UFSD("ino %lu, frag1 %llu, frag2 %llu, block1 %llu, block2 %llu,"
 100              " frag3 %llu, frag4 %llu\n", inode->i_ino,
 101              (unsigned long long)frag1, (unsigned long long)frag2,
 102              (unsigned long long)block1, (unsigned long long)block2,
 103              (unsigned long long)frag3, (unsigned long long)frag4);
 104
 105         if (frag1 >= frag2)
 106                 goto next1;
 107
 108         /*
 109          * Free first free fragments
 110          */
 111         p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag1));
 112         tmp = ufs_data_ptr_to_cpu(sb, p);
 113         if (!tmp )
 114                 ufs_panic (sb, "ufs_trunc_direct", "internal error");
 115         frag2 -= frag1;
 116         frag1 = ufs_fragnum (frag1);
 117
 118         ufs_free_fragments(inode, tmp + frag1, frag2);
 119         mark_inode_dirty(inode);
 120         frag_to_free = tmp + frag1;
 121
 122 next1:
 123         /*
 124          * Free whole blocks
 125          */
 126         for (i = block1 ; i < block2; i++) {
 127                 p = ufs_get_direct_data_ptr(uspi, ufsi, i);
 128                 tmp = ufs_data_ptr_to_cpu(sb, p);
 129                 if (!tmp)
 130                         continue;
 131                 ufs_data_ptr_clear(uspi, p);
 132
 133                 if (free_count == 0) {
 134                         frag_to_free = tmp;
 135                         free_count = uspi->s_fpb;
 136                 } else if (free_count > 0 && frag_to_free == tmp - free_count)
 137                         free_count += uspi->s_fpb;
 138                 else {
 139                         ufs_free_blocks (inode, frag_to_free, free_count);
 140                         frag_to_free = tmp;
 141                         free_count = uspi->s_fpb;
 142                 }
 143                 mark_inode_dirty(inode);
 144         }
 145
 146         if (free_count > 0)
 147                 ufs_free_blocks (inode, frag_to_free, free_count);
 148
 149         if (frag3 >= frag4)
 150                 goto next3;
 151
 152         /*
 153          * Free last free fragments
 154          */
 155         p = ufs_get_direct_data_ptr(uspi, ufsi, ufs_fragstoblks(frag3));
 156         tmp = ufs_data_ptr_to_cpu(sb, p);
 157         if (!tmp )
 158                 ufs_panic(sb, "ufs_truncate_direct", "internal error");
 159         frag4 = ufs_fragnum (frag4);
 160         ufs_data_ptr_clear(uspi, p);
 161
 162         ufs_free_fragments (inode, tmp, frag4);
 163         mark_inode_dirty(inode);
 164  next3:
 165
 166         UFSD("EXIT: ino %lu\n", inode->i_ino);
 167         return retry;
 168 }
 169
 170
 171 static int ufs_trunc_indirect(struct inode *inode, u64 offset, void *p)
 172 {
 173         struct super_block * sb;
 174         struct ufs_sb_private_info * uspi;
 175         struct ufs_buffer_head * ind_ubh;
 176         void *ind;
 177         u64 tmp, indirect_block, i, frag_to_free;
 178         unsigned free_count;
 179         int retry;
 180
 181         UFSD("ENTER: ino %lu, offset %llu, p: %p\n",
 182              inode->i_ino, (unsigned long long)offset, p);
 183
 184         BUG_ON(!p);
 185
 186         sb = inode->i_sb;
 187         uspi = UFS_SB(sb)->s_uspi;
 188
 189         frag_to_free = 0;
 190         free_count = 0;
 191         retry = 0;
 192
 193         tmp = ufs_data_ptr_to_cpu(sb, p);
 194         if (!tmp)
 195                 return 0;
 196         ind_ubh = ubh_bread(sb, tmp, uspi->s_bsize);
 197         if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
 198                 ubh_brelse (ind_ubh);
 199                 return 1;
 200         }
 201         if (!ind_ubh) {
 202                 ufs_data_ptr_clear(uspi, p);
 203                 return 0;
 204         }
 205
 206         indirect_block = (DIRECT_BLOCK > offset) ? (DIRECT_BLOCK - offset) : 0;
 207         for (i = indirect_block; i < uspi->s_apb; i++) {
 208                 ind = ubh_get_data_ptr(uspi, ind_ubh, i);
 209                 tmp = ufs_data_ptr_to_cpu(sb, ind);
 210                 if (!tmp)
 211                         continue;
 212
 213                 ufs_data_ptr_clear(uspi, ind);
 214                 ubh_mark_buffer_dirty(ind_ubh);
 215                 if (free_count == 0) {
 216                         frag_to_free = tmp;
 217                         free_count = uspi->s_fpb;
 218                 } else if (free_count > 0 && frag_to_free == tmp - free_count)
 219                         free_count += uspi->s_fpb;
 220                 else {
 221                         ufs_free_blocks (inode, frag_to_free, free_count);
 222                         frag_to_free = tmp;
 223                         free_count = uspi->s_fpb;
 224                 }
 225
 226                 mark_inode_dirty(inode);
 227         }
 228
 229         if (free_count > 0) {
 230                 ufs_free_blocks (inode, frag_to_free, free_count);
 231         }
 232         for (i = 0; i < uspi->s_apb; i++)
 233                 if (!ufs_is_data_ptr_zero(uspi,
 234                                           ubh_get_data_ptr(uspi, ind_ubh, i)))
 235                         break;
 236         if (i >= uspi->s_apb) {
 237                 tmp = ufs_data_ptr_to_cpu(sb, p);
 238                 ufs_data_ptr_clear(uspi, p);
 239
 240                 ufs_free_blocks (inode, tmp, uspi->s_fpb);
 241                 mark_inode_dirty(inode);
 242                 ubh_bforget(ind_ubh);
 243                 ind_ubh = NULL;
 244         }
 245         if (IS_SYNC(inode) && ind_ubh && ubh_buffer_dirty(ind_ubh))
 246                 ubh_sync_block(ind_ubh);
 247         ubh_brelse (ind_ubh);
 248
 249         UFSD("EXIT: ino %lu\n", inode->i_ino);
 250
 251         return retry;
 252 }
 253
 254 static int ufs_trunc_dindirect(struct inode *inode, u64 offset, void *p)
 255 {
 256         struct super_block * sb;
 257         struct ufs_sb_private_info * uspi;
 258         struct ufs_buffer_head *dind_bh;
 259         u64 i, tmp, dindirect_block;
 260         void *dind;
 261         int retry = 0;
 262
 263         UFSD("ENTER: ino %lu\n", inode->i_ino);
 264
 265         sb = inode->i_sb;
 266         uspi = UFS_SB(sb)->s_uspi;
 267
 268         dindirect_block = (DIRECT_BLOCK > offset)
 269                 ? ((DIRECT_BLOCK - offset) >> uspi->s_apbshift) : 0;
 270         retry = 0;
 271
 272         tmp = ufs_data_ptr_to_cpu(sb, p);
 273         if (!tmp)
 274                 return 0;
 275         dind_bh = ubh_bread(sb, tmp, uspi->s_bsize);
 276         if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
 277                 ubh_brelse (dind_bh);
 278                 return 1;
 279         }
 280         if (!dind_bh) {
 281                 ufs_data_ptr_clear(uspi, p);
 282                 return 0;
 283         }
 284
 285         for (i = dindirect_block ; i < uspi->s_apb ; i++) {
 286                 dind = ubh_get_data_ptr(uspi, dind_bh, i);
 287                 tmp = ufs_data_ptr_to_cpu(sb, dind);
 288                 if (!tmp)
 289                         continue;
 290                 retry |= ufs_trunc_indirect (inode, offset + (i << uspi->s_apbshift), dind);
 291                 ubh_mark_buffer_dirty(dind_bh);
 292         }
 293
 294         for (i = 0; i < uspi->s_apb; i++)
 295                 if (!ufs_is_data_ptr_zero(uspi,
 296                                           ubh_get_data_ptr(uspi, dind_bh, i)))
 297                         break;
 298         if (i >= uspi->s_apb) {
 299                 tmp = ufs_data_ptr_to_cpu(sb, p);
 300                 ufs_data_ptr_clear(uspi, p);
 301
 302                 ufs_free_blocks(inode, tmp, uspi->s_fpb);
 303                 mark_inode_dirty(inode);
 304                 ubh_bforget(dind_bh);
 305                 dind_bh = NULL;
 306         }
 307         if (IS_SYNC(inode) && dind_bh && ubh_buffer_dirty(dind_bh))
 308                 ubh_sync_block(dind_bh);
 309         ubh_brelse (dind_bh);
 310
 311         UFSD("EXIT: ino %lu\n", inode->i_ino);
 312
 313         return retry;
 314 }
 315
 316 static int ufs_trunc_tindirect(struct inode *inode)
 317 {
 318         struct super_block *sb = inode->i_sb;
 319         struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
 320         struct ufs_inode_info *ufsi = UFS_I(inode);
 321         struct ufs_buffer_head * tind_bh;
 322         u64 tindirect_block, tmp, i;
 323         void *tind, *p;
 324         int retry;
 325
 326         UFSD("ENTER: ino %lu\n", inode->i_ino);
 327
 328         retry = 0;
 329
 330         tindirect_block = (DIRECT_BLOCK > (UFS_NDADDR + uspi->s_apb + uspi->s_2apb))
 331                 ? ((DIRECT_BLOCK - UFS_NDADDR - uspi->s_apb - uspi->s_2apb) >> uspi->s_2apbshift) : 0;
 332
 333         p = ufs_get_direct_data_ptr(uspi, ufsi, UFS_TIND_BLOCK);
 334         if (!(tmp = ufs_data_ptr_to_cpu(sb, p)))
 335                 return 0;
 336         tind_bh = ubh_bread (sb, tmp, uspi->s_bsize);
 337         if (tmp != ufs_data_ptr_to_cpu(sb, p)) {
 338                 ubh_brelse (tind_bh);
 339                 return 1;
 340         }
 341         if (!tind_bh) {
 342                 ufs_data_ptr_clear(uspi, p);
 343                 return 0;
 344         }
 345
 346         for (i = tindirect_block ; i < uspi->s_apb ; i++) {
 347                 tind = ubh_get_data_ptr(uspi, tind_bh, i);
 348                 retry |= ufs_trunc_dindirect(inode, UFS_NDADDR +
 349                         uspi->s_apb + ((i + 1) << uspi->s_2apbshift), tind);
 350                 ubh_mark_buffer_dirty(tind_bh);
 351         }
 352         for (i = 0; i < uspi->s_apb; i++)
 353                 if (!ufs_is_data_ptr_zero(uspi,
 354                                           ubh_get_data_ptr(uspi, tind_bh, i)))
 355                         break;
 356         if (i >= uspi->s_apb) {
 357                 tmp = ufs_data_ptr_to_cpu(sb, p);
 358                 ufs_data_ptr_clear(uspi, p);
 359
 360                 ufs_free_blocks(inode, tmp, uspi->s_fpb);
 361                 mark_inode_dirty(inode);
 362                 ubh_bforget(tind_bh);
 363                 tind_bh = NULL;
 364         }
 365         if (IS_SYNC(inode) && tind_bh && ubh_buffer_dirty(tind_bh))
 366                 ubh_sync_block(tind_bh);
 367         ubh_brelse (tind_bh);
 368
 369         UFSD("EXIT: ino %lu\n", inode->i_ino);
 370         return retry;
 371 }
 372
 373 static int ufs_alloc_lastblock(struct inode *inode)
 374 {
 375         int err = 0;
 376         struct super_block *sb = inode->i_sb;
 377         struct address_space *mapping = inode->i_mapping;
 378         struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
 379         unsigned i, end;
 380         sector_t lastfrag;
 381         struct page *lastpage;
 382         struct buffer_head *bh;
 383         u64 phys64;
 384
 385         lastfrag = (i_size_read(inode) + uspi->s_fsize - 1) >> uspi->s_fshift;
 386
 387         if (!lastfrag)
 388                 goto out;
 389
 390         lastfrag--;
 391
 392         lastpage = ufs_get_locked_page(mapping, lastfrag >>
 393                                        (PAGE_CACHE_SHIFT - inode->i_blkbits));
 394        if (IS_ERR(lastpage)) {
 395                err = -EIO;
 396                goto out;
 397        }
 398
 399        end = lastfrag & ((1 << (PAGE_CACHE_SHIFT - inode->i_blkbits)) - 1);
 400        bh = page_buffers(lastpage);
 401        for (i = 0; i < end; ++i)
 402                bh = bh->b_this_page;
 403
 404
 405        err = ufs_getfrag_block(inode, lastfrag, bh, 1);
 406
 407        if (unlikely(err))
 408                goto out_unlock;
 409
 410        if (buffer_new(bh)) {
 411                clear_buffer_new(bh);
 412                unmap_underlying_metadata(bh->b_bdev,
 413                                          bh->b_blocknr);
 414                /*
 415                 * we do not zeroize fragment, because of
 416                 * if it maped to hole, it already contains zeroes
 417                 */
 418                set_buffer_uptodate(bh);
 419                mark_buffer_dirty(bh);
 420                set_page_dirty(lastpage);
 421        }
 422
 423        if (lastfrag >= UFS_IND_FRAGMENT) {
 424                end = uspi->s_fpb - ufs_fragnum(lastfrag) - 1;
 425                phys64 = bh->b_blocknr + 1;
 426                for (i = 0; i < end; ++i) {
 427                        bh = sb_getblk(sb, i + phys64);
 428                        lock_buffer(bh);
 429                        memset(bh->b_data, 0, sb->s_blocksize);
 430                        set_buffer_uptodate(bh);
 431                        mark_buffer_dirty(bh);
 432                        unlock_buffer(bh);
 433                        sync_dirty_buffer(bh);
 434                        brelse(bh);
 435                }
 436        }
 437 out_unlock:
 438        ufs_put_locked_page(lastpage);
 439 out:
 440        return err;
 441 }
 442
 443 int ufs_truncate(struct inode *inode, loff_t old_i_size)
 444 {
 445         struct ufs_inode_info *ufsi = UFS_I(inode);
 446         struct super_block *sb = inode->i_sb;
 447         struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
 448         int retry, err = 0;
 449
 450         UFSD("ENTER: ino %lu, i_size: %llu, old_i_size: %llu\n",
 451              inode->i_ino, (unsigned long long)i_size_read(inode),
 452              (unsigned long long)old_i_size);
 453
 454         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 455               S_ISLNK(inode->i_mode)))
 456                 return -EINVAL;
 457         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 458                 return -EPERM;
 459
 460         err = ufs_alloc_lastblock(inode);
 461
 462         if (err) {
 463                 i_size_write(inode, old_i_size);
 464                 goto out;
 465         }
 466
 467         block_truncate_page(inode->i_mapping, inode->i_size, ufs_getfrag_block);
 468
 469         while (1) {
 470                 retry = ufs_trunc_direct(inode);
 471                 retry |= ufs_trunc_indirect(inode, UFS_IND_BLOCK,
 472                                             ufs_get_direct_data_ptr(uspi, ufsi,
 473                                                                     UFS_IND_BLOCK));
 474                 retry |= ufs_trunc_dindirect(inode, UFS_IND_BLOCK + uspi->s_apb,
 475                                              ufs_get_direct_data_ptr(uspi, ufsi,
 476                                                                      UFS_DIND_BLOCK));
 477                 retry |= ufs_trunc_tindirect (inode);
 478                 if (!retry)
 479                         break;
 480                 if (IS_SYNC(inode) && (inode->i_state & I_DIRTY))
 481                         ufs_sync_inode (inode);
 482                 blk_flush_plug(current);
 483                 yield();
 484         }
 485
 486         inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
 487         ufsi->i_lastfrag = DIRECT_FRAGMENT;
 488         mark_inode_dirty(inode);
 489 out:
 490         UFSD("EXIT: err %d\n", err);
 491         return err;
 492 }
 493
 494 int ufs_setattr(struct dentry *dentry, struct iattr *attr)
 495 {
 496         struct inode *inode = dentry->d_inode;
 497         unsigned int ia_valid = attr->ia_valid;
 498         int error;
 499
 500         error = inode_change_ok(inode, attr);
 501         if (error)
 502                 return error;
 503
 504         if (ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
 505                 loff_t old_i_size = inode->i_size;
 506
 507                 /* XXX(truncate): truncate_setsize should be called last */
 508                 truncate_setsize(inode, attr->ia_size);
 509
 510                 lock_ufs(inode->i_sb);
 511                 error = ufs_truncate(inode, old_i_size);
 512                 unlock_ufs(inode->i_sb);
 513                 if (error)
 514                         return error;
 515         }
 516
 517         setattr_copy(inode, attr);
 518         mark_inode_dirty(inode);
 519         return 0;
 520 }
 521
 522 const struct inode_operations ufs_file_inode_operations = {
 523         .setattr = ufs_setattr,
 524 };