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 66static 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(u64, 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 122next1: 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 171static 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 254static 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 316static 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 373static 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 } 437out_unlock: 438 ufs_put_locked_page(lastpage); 439out: 440 return err; 441} 442 443int 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 yield(); 483 } 484 485 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; 486 ufsi->i_lastfrag = DIRECT_FRAGMENT; 487 mark_inode_dirty(inode); 488out: 489 UFSD("EXIT: err %d\n", err); 490 return err; 491} 492 493int ufs_setattr(struct dentry *dentry, struct iattr *attr) 494{ 495 struct inode *inode = d_inode(dentry); 496 unsigned int ia_valid = attr->ia_valid; 497 int error; 498 499 error = inode_change_ok(inode, attr); 500 if (error) 501 return error; 502 503 if (ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) { 504 loff_t old_i_size = inode->i_size; 505 506 /* XXX(truncate): truncate_setsize should be called last */ 507 truncate_setsize(inode, attr->ia_size); 508 509 lock_ufs(inode->i_sb); 510 error = ufs_truncate(inode, old_i_size); 511 unlock_ufs(inode->i_sb); 512 if (error) 513 return error; 514 } 515 516 setattr_copy(inode, attr); 517 mark_inode_dirty(inode); 518 return 0; 519} 520 521const struct inode_operations ufs_file_inode_operations = { 522 .setattr = ufs_setattr, 523}; 524