1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. 4 */ 5 6 #include <linux/slab.h> 7 #include <linux/compat.h> 8 #include <linux/cred.h> 9 #include <linux/buffer_head.h> 10 #include <linux/blkdev.h> 11 #include <linux/fsnotify.h> 12 #include <linux/security.h> 13 #include <linux/msdos_fs.h> 14 #include <linux/writeback.h> 15 16 #include "exfat_raw.h" 17 #include "exfat_fs.h" 18 19 static int exfat_cont_expand(struct inode *inode, loff_t size) 20 { 21 int ret; 22 unsigned int num_clusters, new_num_clusters, last_clu; 23 struct exfat_inode_info *ei = EXFAT_I(inode); 24 struct super_block *sb = inode->i_sb; 25 struct exfat_sb_info *sbi = EXFAT_SB(sb); 26 struct exfat_chain clu; 27 28 truncate_pagecache(inode, i_size_read(inode)); 29 30 ret = inode_newsize_ok(inode, size); 31 if (ret) 32 return ret; 33 34 num_clusters = EXFAT_B_TO_CLU(exfat_ondisk_size(inode), sbi); 35 new_num_clusters = EXFAT_B_TO_CLU_ROUND_UP(size, sbi); 36 37 if (new_num_clusters == num_clusters) 38 goto out; 39 40 if (num_clusters) { 41 exfat_chain_set(&clu, ei->start_clu, num_clusters, ei->flags); 42 ret = exfat_find_last_cluster(sb, &clu, &last_clu); 43 if (ret) 44 return ret; 45 46 clu.dir = last_clu + 1; 47 } else { 48 last_clu = EXFAT_EOF_CLUSTER; 49 clu.dir = EXFAT_EOF_CLUSTER; 50 } 51 52 clu.size = 0; 53 clu.flags = ei->flags; 54 55 ret = exfat_alloc_cluster(inode, new_num_clusters - num_clusters, 56 &clu, inode_needs_sync(inode)); 57 if (ret) 58 return ret; 59 60 /* Append new clusters to chain */ 61 if (num_clusters) { 62 if (clu.flags != ei->flags) 63 if (exfat_chain_cont_cluster(sb, ei->start_clu, num_clusters)) 64 goto free_clu; 65 66 if (clu.flags == ALLOC_FAT_CHAIN) 67 if (exfat_ent_set(sb, last_clu, clu.dir)) 68 goto free_clu; 69 } else 70 ei->start_clu = clu.dir; 71 72 ei->flags = clu.flags; 73 74 out: 75 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); 76 /* Expanded range not zeroed, do not update valid_size */ 77 i_size_write(inode, size); 78 79 inode->i_blocks = round_up(size, sbi->cluster_size) >> 9; 80 mark_inode_dirty(inode); 81 82 if (IS_SYNC(inode)) 83 return write_inode_now(inode, 1); 84 85 return 0; 86 87 free_clu: 88 exfat_free_cluster(inode, &clu); 89 return -EIO; 90 } 91 92 static bool exfat_allow_set_time(struct mnt_idmap *idmap, 93 struct exfat_sb_info *sbi, struct inode *inode) 94 { 95 mode_t allow_utime = sbi->options.allow_utime; 96 97 if (!vfsuid_eq_kuid(i_uid_into_vfsuid(idmap, inode), 98 current_fsuid())) { 99 if (vfsgid_in_group_p(i_gid_into_vfsgid(idmap, inode))) 100 allow_utime >>= 3; 101 if (allow_utime & MAY_WRITE) 102 return true; 103 } 104 105 /* use a default check */ 106 return false; 107 } 108 109 static int exfat_sanitize_mode(const struct exfat_sb_info *sbi, 110 struct inode *inode, umode_t *mode_ptr) 111 { 112 mode_t i_mode, mask, perm; 113 114 i_mode = inode->i_mode; 115 116 mask = (S_ISREG(i_mode) || S_ISLNK(i_mode)) ? 117 sbi->options.fs_fmask : sbi->options.fs_dmask; 118 perm = *mode_ptr & ~(S_IFMT | mask); 119 120 /* Of the r and x bits, all (subject to umask) must be present.*/ 121 if ((perm & 0555) != (i_mode & 0555)) 122 return -EPERM; 123 124 if (exfat_mode_can_hold_ro(inode)) { 125 /* 126 * Of the w bits, either all (subject to umask) or none must 127 * be present. 128 */ 129 if ((perm & 0222) && ((perm & 0222) != (0222 & ~mask))) 130 return -EPERM; 131 } else { 132 /* 133 * If exfat_mode_can_hold_ro(inode) is false, can't change 134 * w bits. 135 */ 136 if ((perm & 0222) != (0222 & ~mask)) 137 return -EPERM; 138 } 139 140 *mode_ptr &= S_IFMT | perm; 141 142 return 0; 143 } 144 145 /* resize the file length */ 146 int __exfat_truncate(struct inode *inode) 147 { 148 unsigned int num_clusters_new, num_clusters_phys; 149 unsigned int last_clu = EXFAT_FREE_CLUSTER; 150 struct exfat_chain clu; 151 struct super_block *sb = inode->i_sb; 152 struct exfat_sb_info *sbi = EXFAT_SB(sb); 153 struct exfat_inode_info *ei = EXFAT_I(inode); 154 155 /* check if the given file ID is opened */ 156 if (ei->type != TYPE_FILE && ei->type != TYPE_DIR) 157 return -EPERM; 158 159 exfat_set_volume_dirty(sb); 160 161 num_clusters_new = EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi); 162 num_clusters_phys = EXFAT_B_TO_CLU(exfat_ondisk_size(inode), sbi); 163 164 exfat_chain_set(&clu, ei->start_clu, num_clusters_phys, ei->flags); 165 166 if (i_size_read(inode) > 0) { 167 /* 168 * Truncate FAT chain num_clusters after the first cluster 169 * num_clusters = min(new, phys); 170 */ 171 unsigned int num_clusters = 172 min(num_clusters_new, num_clusters_phys); 173 174 /* 175 * Follow FAT chain 176 * (defensive coding - works fine even with corrupted FAT table 177 */ 178 if (clu.flags == ALLOC_NO_FAT_CHAIN) { 179 clu.dir += num_clusters; 180 clu.size -= num_clusters; 181 } else { 182 while (num_clusters > 0) { 183 last_clu = clu.dir; 184 if (exfat_get_next_cluster(sb, &(clu.dir))) 185 return -EIO; 186 187 num_clusters--; 188 clu.size--; 189 } 190 } 191 } else { 192 ei->flags = ALLOC_NO_FAT_CHAIN; 193 ei->start_clu = EXFAT_EOF_CLUSTER; 194 } 195 196 if (i_size_read(inode) < ei->valid_size) 197 ei->valid_size = i_size_read(inode); 198 199 if (ei->type == TYPE_FILE) 200 ei->attr |= EXFAT_ATTR_ARCHIVE; 201 202 /* 203 * update the directory entry 204 * 205 * If the directory entry is updated by mark_inode_dirty(), the 206 * directory entry will be written after a writeback cycle of 207 * updating the bitmap/FAT, which may result in clusters being 208 * freed but referenced by the directory entry in the event of a 209 * sudden power failure. 210 * __exfat_write_inode() is called for directory entry, bitmap 211 * and FAT to be written in a same writeback. 212 */ 213 if (__exfat_write_inode(inode, inode_needs_sync(inode))) 214 return -EIO; 215 216 /* cut off from the FAT chain */ 217 if (ei->flags == ALLOC_FAT_CHAIN && last_clu != EXFAT_FREE_CLUSTER && 218 last_clu != EXFAT_EOF_CLUSTER) { 219 if (exfat_ent_set(sb, last_clu, EXFAT_EOF_CLUSTER)) 220 return -EIO; 221 } 222 223 /* invalidate cache and free the clusters */ 224 /* clear exfat cache */ 225 exfat_cache_inval_inode(inode); 226 227 /* hint information */ 228 ei->hint_bmap.off = EXFAT_EOF_CLUSTER; 229 ei->hint_bmap.clu = EXFAT_EOF_CLUSTER; 230 231 /* hint_stat will be used if this is directory. */ 232 ei->hint_stat.eidx = 0; 233 ei->hint_stat.clu = ei->start_clu; 234 ei->hint_femp.eidx = EXFAT_HINT_NONE; 235 236 /* free the clusters */ 237 if (exfat_free_cluster(inode, &clu)) 238 return -EIO; 239 240 return 0; 241 } 242 243 void exfat_truncate(struct inode *inode) 244 { 245 struct super_block *sb = inode->i_sb; 246 struct exfat_sb_info *sbi = EXFAT_SB(sb); 247 struct exfat_inode_info *ei = EXFAT_I(inode); 248 int err; 249 250 mutex_lock(&sbi->s_lock); 251 if (ei->start_clu == 0) { 252 /* 253 * Empty start_clu != ~0 (not allocated) 254 */ 255 exfat_fs_error(sb, "tried to truncate zeroed cluster."); 256 goto write_size; 257 } 258 259 err = __exfat_truncate(inode); 260 if (err) 261 goto write_size; 262 263 inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9; 264 write_size: 265 mutex_unlock(&sbi->s_lock); 266 } 267 268 int exfat_getattr(struct mnt_idmap *idmap, const struct path *path, 269 struct kstat *stat, unsigned int request_mask, 270 unsigned int query_flags) 271 { 272 struct inode *inode = d_backing_inode(path->dentry); 273 struct exfat_inode_info *ei = EXFAT_I(inode); 274 275 generic_fillattr(idmap, request_mask, inode, stat); 276 exfat_truncate_atime(&stat->atime); 277 stat->result_mask |= STATX_BTIME; 278 stat->btime.tv_sec = ei->i_crtime.tv_sec; 279 stat->btime.tv_nsec = ei->i_crtime.tv_nsec; 280 stat->blksize = EXFAT_SB(inode->i_sb)->cluster_size; 281 return 0; 282 } 283 284 int exfat_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 285 struct iattr *attr) 286 { 287 struct exfat_sb_info *sbi = EXFAT_SB(dentry->d_sb); 288 struct inode *inode = dentry->d_inode; 289 unsigned int ia_valid; 290 int error; 291 292 if (unlikely(exfat_forced_shutdown(inode->i_sb))) 293 return -EIO; 294 295 if ((attr->ia_valid & ATTR_SIZE) && 296 attr->ia_size > i_size_read(inode)) { 297 error = exfat_cont_expand(inode, attr->ia_size); 298 if (error || attr->ia_valid == ATTR_SIZE) 299 return error; 300 attr->ia_valid &= ~ATTR_SIZE; 301 } 302 303 /* Check for setting the inode time. */ 304 ia_valid = attr->ia_valid; 305 if ((ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) && 306 exfat_allow_set_time(idmap, sbi, inode)) { 307 attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET | 308 ATTR_TIMES_SET); 309 } 310 311 error = setattr_prepare(idmap, dentry, attr); 312 attr->ia_valid = ia_valid; 313 if (error) 314 goto out; 315 316 if (((attr->ia_valid & ATTR_UID) && 317 (!uid_eq(from_vfsuid(idmap, i_user_ns(inode), attr->ia_vfsuid), 318 sbi->options.fs_uid))) || 319 ((attr->ia_valid & ATTR_GID) && 320 (!gid_eq(from_vfsgid(idmap, i_user_ns(inode), attr->ia_vfsgid), 321 sbi->options.fs_gid))) || 322 ((attr->ia_valid & ATTR_MODE) && 323 (attr->ia_mode & ~(S_IFREG | S_IFLNK | S_IFDIR | 0777)))) { 324 error = -EPERM; 325 goto out; 326 } 327 328 /* 329 * We don't return -EPERM here. Yes, strange, but this is too 330 * old behavior. 331 */ 332 if (attr->ia_valid & ATTR_MODE) { 333 if (exfat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0) 334 attr->ia_valid &= ~ATTR_MODE; 335 } 336 337 if (attr->ia_valid & ATTR_SIZE) 338 inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode)); 339 340 setattr_copy(idmap, inode, attr); 341 exfat_truncate_inode_atime(inode); 342 343 if (attr->ia_valid & ATTR_SIZE) { 344 error = exfat_block_truncate_page(inode, attr->ia_size); 345 if (error) 346 goto out; 347 348 down_write(&EXFAT_I(inode)->truncate_lock); 349 truncate_setsize(inode, attr->ia_size); 350 351 /* 352 * __exfat_write_inode() is called from exfat_truncate(), inode 353 * is already written by it, so mark_inode_dirty() is unneeded. 354 */ 355 exfat_truncate(inode); 356 up_write(&EXFAT_I(inode)->truncate_lock); 357 } else 358 mark_inode_dirty(inode); 359 360 out: 361 return error; 362 } 363 364 /* 365 * modified ioctls from fat/file.c by Welmer Almesberger 366 */ 367 static int exfat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr) 368 { 369 u32 attr; 370 371 inode_lock_shared(inode); 372 attr = exfat_make_attr(inode); 373 inode_unlock_shared(inode); 374 375 return put_user(attr, user_attr); 376 } 377 378 static int exfat_ioctl_set_attributes(struct file *file, u32 __user *user_attr) 379 { 380 struct inode *inode = file_inode(file); 381 struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb); 382 int is_dir = S_ISDIR(inode->i_mode); 383 u32 attr, oldattr; 384 struct iattr ia; 385 int err; 386 387 err = get_user(attr, user_attr); 388 if (err) 389 goto out; 390 391 err = mnt_want_write_file(file); 392 if (err) 393 goto out; 394 inode_lock(inode); 395 396 oldattr = exfat_make_attr(inode); 397 398 /* 399 * Mask attributes so we don't set reserved fields. 400 */ 401 attr &= (EXFAT_ATTR_READONLY | EXFAT_ATTR_HIDDEN | EXFAT_ATTR_SYSTEM | 402 EXFAT_ATTR_ARCHIVE); 403 attr |= (is_dir ? EXFAT_ATTR_SUBDIR : 0); 404 405 /* Equivalent to a chmod() */ 406 ia.ia_valid = ATTR_MODE | ATTR_CTIME; 407 ia.ia_ctime = current_time(inode); 408 if (is_dir) 409 ia.ia_mode = exfat_make_mode(sbi, attr, 0777); 410 else 411 ia.ia_mode = exfat_make_mode(sbi, attr, 0666 | (inode->i_mode & 0111)); 412 413 /* The root directory has no attributes */ 414 if (inode->i_ino == EXFAT_ROOT_INO && attr != EXFAT_ATTR_SUBDIR) { 415 err = -EINVAL; 416 goto out_unlock_inode; 417 } 418 419 if (((attr | oldattr) & EXFAT_ATTR_SYSTEM) && 420 !capable(CAP_LINUX_IMMUTABLE)) { 421 err = -EPERM; 422 goto out_unlock_inode; 423 } 424 425 /* 426 * The security check is questionable... We single 427 * out the RO attribute for checking by the security 428 * module, just because it maps to a file mode. 429 */ 430 err = security_inode_setattr(file_mnt_idmap(file), 431 file->f_path.dentry, &ia); 432 if (err) 433 goto out_unlock_inode; 434 435 /* This MUST be done before doing anything irreversible... */ 436 err = exfat_setattr(file_mnt_idmap(file), file->f_path.dentry, &ia); 437 if (err) 438 goto out_unlock_inode; 439 440 fsnotify_change(file->f_path.dentry, ia.ia_valid); 441 442 exfat_save_attr(inode, attr); 443 mark_inode_dirty(inode); 444 out_unlock_inode: 445 inode_unlock(inode); 446 mnt_drop_write_file(file); 447 out: 448 return err; 449 } 450 451 static int exfat_ioctl_fitrim(struct inode *inode, unsigned long arg) 452 { 453 struct fstrim_range range; 454 int ret = 0; 455 456 if (!capable(CAP_SYS_ADMIN)) 457 return -EPERM; 458 459 if (!bdev_max_discard_sectors(inode->i_sb->s_bdev)) 460 return -EOPNOTSUPP; 461 462 if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range))) 463 return -EFAULT; 464 465 range.minlen = max_t(unsigned int, range.minlen, 466 bdev_discard_granularity(inode->i_sb->s_bdev)); 467 468 ret = exfat_trim_fs(inode, &range); 469 if (ret < 0) 470 return ret; 471 472 if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range))) 473 return -EFAULT; 474 475 return 0; 476 } 477 478 static int exfat_ioctl_shutdown(struct super_block *sb, unsigned long arg) 479 { 480 u32 flags; 481 482 if (!capable(CAP_SYS_ADMIN)) 483 return -EPERM; 484 485 if (get_user(flags, (__u32 __user *)arg)) 486 return -EFAULT; 487 488 return exfat_force_shutdown(sb, flags); 489 } 490 491 static int exfat_ioctl_get_volume_label(struct super_block *sb, unsigned long arg) 492 { 493 int ret; 494 char label[FSLABEL_MAX] = {0}; 495 struct exfat_uni_name uniname; 496 497 ret = exfat_read_volume_label(sb, &uniname); 498 if (ret < 0) 499 return ret; 500 501 ret = exfat_utf16_to_nls(sb, &uniname, label, uniname.name_len); 502 if (ret < 0) 503 return ret; 504 505 if (copy_to_user((char __user *)arg, label, ret + 1)) 506 return -EFAULT; 507 508 return 0; 509 } 510 511 static int exfat_ioctl_set_volume_label(struct super_block *sb, 512 unsigned long arg) 513 { 514 int ret = 0, lossy, label_len; 515 char label[FSLABEL_MAX] = {0}; 516 struct exfat_uni_name uniname; 517 518 if (!capable(CAP_SYS_ADMIN)) 519 return -EPERM; 520 521 if (copy_from_user(label, (char __user *)arg, FSLABEL_MAX)) 522 return -EFAULT; 523 524 memset(&uniname, 0, sizeof(uniname)); 525 label_len = strnlen(label, FSLABEL_MAX - 1); 526 if (label[0]) { 527 ret = exfat_nls_to_utf16(sb, label, label_len, 528 &uniname, &lossy); 529 if (ret < 0) 530 return ret; 531 else if (lossy & NLS_NAME_LOSSY) 532 return -EINVAL; 533 } 534 535 uniname.name_len = ret; 536 537 return exfat_write_volume_label(sb, &uniname); 538 } 539 540 long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 541 { 542 struct inode *inode = file_inode(filp); 543 u32 __user *user_attr = (u32 __user *)arg; 544 545 switch (cmd) { 546 case FAT_IOCTL_GET_ATTRIBUTES: 547 return exfat_ioctl_get_attributes(inode, user_attr); 548 case FAT_IOCTL_SET_ATTRIBUTES: 549 return exfat_ioctl_set_attributes(filp, user_attr); 550 case EXFAT_IOC_SHUTDOWN: 551 return exfat_ioctl_shutdown(inode->i_sb, arg); 552 case FITRIM: 553 return exfat_ioctl_fitrim(inode, arg); 554 case FS_IOC_GETFSLABEL: 555 return exfat_ioctl_get_volume_label(inode->i_sb, arg); 556 case FS_IOC_SETFSLABEL: 557 return exfat_ioctl_set_volume_label(inode->i_sb, arg); 558 default: 559 return -ENOTTY; 560 } 561 } 562 563 #ifdef CONFIG_COMPAT 564 long exfat_compat_ioctl(struct file *filp, unsigned int cmd, 565 unsigned long arg) 566 { 567 return exfat_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); 568 } 569 #endif 570 571 int exfat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) 572 { 573 struct inode *inode = filp->f_mapping->host; 574 int err; 575 576 if (unlikely(exfat_forced_shutdown(inode->i_sb))) 577 return -EIO; 578 579 err = __generic_file_fsync(filp, start, end, datasync); 580 if (err) 581 return err; 582 583 err = sync_blockdev(inode->i_sb->s_bdev); 584 if (err) 585 return err; 586 587 return blkdev_issue_flush(inode->i_sb->s_bdev); 588 } 589 590 static int exfat_extend_valid_size(struct inode *inode, loff_t new_valid_size) 591 { 592 int err; 593 loff_t pos; 594 struct exfat_inode_info *ei = EXFAT_I(inode); 595 struct address_space *mapping = inode->i_mapping; 596 const struct address_space_operations *ops = mapping->a_ops; 597 598 pos = ei->valid_size; 599 while (pos < new_valid_size) { 600 u32 len; 601 struct folio *folio; 602 unsigned long off; 603 604 len = PAGE_SIZE - (pos & (PAGE_SIZE - 1)); 605 if (pos + len > new_valid_size) 606 len = new_valid_size - pos; 607 608 err = ops->write_begin(NULL, mapping, pos, len, &folio, NULL); 609 if (err) 610 goto out; 611 612 off = offset_in_folio(folio, pos); 613 folio_zero_new_buffers(folio, off, off + len); 614 615 err = ops->write_end(NULL, mapping, pos, len, len, folio, NULL); 616 if (err < 0) 617 goto out; 618 pos += len; 619 620 balance_dirty_pages_ratelimited(mapping); 621 cond_resched(); 622 } 623 624 return 0; 625 626 out: 627 return err; 628 } 629 630 static ssize_t exfat_file_write_iter(struct kiocb *iocb, struct iov_iter *iter) 631 { 632 ssize_t ret; 633 struct file *file = iocb->ki_filp; 634 struct inode *inode = file_inode(file); 635 struct exfat_inode_info *ei = EXFAT_I(inode); 636 loff_t pos = iocb->ki_pos; 637 loff_t valid_size; 638 639 if (unlikely(exfat_forced_shutdown(inode->i_sb))) 640 return -EIO; 641 642 inode_lock(inode); 643 644 if (pos > i_size_read(inode)) 645 truncate_pagecache(inode, i_size_read(inode)); 646 647 valid_size = ei->valid_size; 648 649 ret = generic_write_checks(iocb, iter); 650 if (ret <= 0) 651 goto unlock; 652 653 if (iocb->ki_flags & IOCB_DIRECT) { 654 unsigned long align = pos | iov_iter_alignment(iter); 655 656 if (!IS_ALIGNED(align, i_blocksize(inode)) && 657 !IS_ALIGNED(align, bdev_logical_block_size(inode->i_sb->s_bdev))) { 658 ret = -EINVAL; 659 goto unlock; 660 } 661 } 662 663 if (pos > valid_size) { 664 ret = exfat_extend_valid_size(inode, pos); 665 if (ret < 0 && ret != -ENOSPC) { 666 exfat_err(inode->i_sb, 667 "write: fail to zero from %llu to %llu(%zd)", 668 valid_size, pos, ret); 669 } 670 if (ret < 0) 671 goto unlock; 672 } 673 674 ret = __generic_file_write_iter(iocb, iter); 675 if (ret < 0) 676 goto unlock; 677 678 inode_unlock(inode); 679 680 if (pos > valid_size) 681 pos = valid_size; 682 683 if (iocb->ki_pos > pos) { 684 ssize_t err = generic_write_sync(iocb, iocb->ki_pos - pos); 685 if (err < 0) 686 return err; 687 } 688 689 return ret; 690 691 unlock: 692 inode_unlock(inode); 693 694 return ret; 695 } 696 697 static ssize_t exfat_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) 698 { 699 struct inode *inode = file_inode(iocb->ki_filp); 700 701 if (unlikely(exfat_forced_shutdown(inode->i_sb))) 702 return -EIO; 703 704 return generic_file_read_iter(iocb, iter); 705 } 706 707 static vm_fault_t exfat_page_mkwrite(struct vm_fault *vmf) 708 { 709 int err; 710 struct vm_area_struct *vma = vmf->vma; 711 struct file *file = vma->vm_file; 712 struct inode *inode = file_inode(file); 713 struct exfat_inode_info *ei = EXFAT_I(inode); 714 loff_t start, end; 715 716 if (!inode_trylock(inode)) 717 return VM_FAULT_RETRY; 718 719 start = ((loff_t)vma->vm_pgoff << PAGE_SHIFT); 720 end = min_t(loff_t, i_size_read(inode), 721 start + vma->vm_end - vma->vm_start); 722 723 if (ei->valid_size < end) { 724 err = exfat_extend_valid_size(inode, end); 725 if (err < 0) { 726 inode_unlock(inode); 727 return vmf_fs_error(err); 728 } 729 } 730 731 inode_unlock(inode); 732 733 return filemap_page_mkwrite(vmf); 734 } 735 736 static const struct vm_operations_struct exfat_file_vm_ops = { 737 .fault = filemap_fault, 738 .map_pages = filemap_map_pages, 739 .page_mkwrite = exfat_page_mkwrite, 740 }; 741 742 static int exfat_file_mmap_prepare(struct vm_area_desc *desc) 743 { 744 struct file *file = desc->file; 745 746 if (unlikely(exfat_forced_shutdown(file_inode(desc->file)->i_sb))) 747 return -EIO; 748 749 file_accessed(file); 750 desc->vm_ops = &exfat_file_vm_ops; 751 return 0; 752 } 753 754 static ssize_t exfat_splice_read(struct file *in, loff_t *ppos, 755 struct pipe_inode_info *pipe, size_t len, unsigned int flags) 756 { 757 if (unlikely(exfat_forced_shutdown(file_inode(in)->i_sb))) 758 return -EIO; 759 760 return filemap_splice_read(in, ppos, pipe, len, flags); 761 } 762 763 const struct file_operations exfat_file_operations = { 764 .llseek = generic_file_llseek, 765 .read_iter = exfat_file_read_iter, 766 .write_iter = exfat_file_write_iter, 767 .unlocked_ioctl = exfat_ioctl, 768 #ifdef CONFIG_COMPAT 769 .compat_ioctl = exfat_compat_ioctl, 770 #endif 771 .mmap_prepare = exfat_file_mmap_prepare, 772 .fsync = exfat_file_fsync, 773 .splice_read = exfat_splice_read, 774 .splice_write = iter_file_splice_write, 775 }; 776 777 const struct inode_operations exfat_file_inode_operations = { 778 .setattr = exfat_setattr, 779 .getattr = exfat_getattr, 780 }; 781