1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/ext4/file.c 4 * 5 * Copyright (C) 1992, 1993, 1994, 1995 6 * Remy Card (card@masi.ibp.fr) 7 * Laboratoire MASI - Institut Blaise Pascal 8 * Universite Pierre et Marie Curie (Paris VI) 9 * 10 * from 11 * 12 * linux/fs/minix/file.c 13 * 14 * Copyright (C) 1991, 1992 Linus Torvalds 15 * 16 * ext4 fs regular file handling primitives 17 * 18 * 64-bit file support on 64-bit platforms by Jakub Jelinek 19 * (jj@sunsite.ms.mff.cuni.cz) 20 */ 21 22 #include <linux/time.h> 23 #include <linux/fs.h> 24 #include <linux/iomap.h> 25 #include <linux/mount.h> 26 #include <linux/path.h> 27 #include <linux/dax.h> 28 #include <linux/quotaops.h> 29 #include <linux/pagevec.h> 30 #include <linux/uio.h> 31 #include <linux/mman.h> 32 #include <linux/backing-dev.h> 33 #include "ext4.h" 34 #include "ext4_jbd2.h" 35 #include "xattr.h" 36 #include "acl.h" 37 #include "truncate.h" 38 39 static bool ext4_dio_supported(struct inode *inode) 40 { 41 if (IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENCRYPTED(inode)) 42 return false; 43 if (fsverity_active(inode)) 44 return false; 45 if (ext4_should_journal_data(inode)) 46 return false; 47 if (ext4_has_inline_data(inode)) 48 return false; 49 return true; 50 } 51 52 static ssize_t ext4_dio_read_iter(struct kiocb *iocb, struct iov_iter *to) 53 { 54 ssize_t ret; 55 struct inode *inode = file_inode(iocb->ki_filp); 56 57 if (iocb->ki_flags & IOCB_NOWAIT) { 58 if (!inode_trylock_shared(inode)) 59 return -EAGAIN; 60 } else { 61 inode_lock_shared(inode); 62 } 63 64 if (!ext4_dio_supported(inode)) { 65 inode_unlock_shared(inode); 66 /* 67 * Fallback to buffered I/O if the operation being performed on 68 * the inode is not supported by direct I/O. The IOCB_DIRECT 69 * flag needs to be cleared here in order to ensure that the 70 * direct I/O path within generic_file_read_iter() is not 71 * taken. 72 */ 73 iocb->ki_flags &= ~IOCB_DIRECT; 74 return generic_file_read_iter(iocb, to); 75 } 76 77 ret = iomap_dio_rw(iocb, to, &ext4_iomap_ops, NULL, 78 is_sync_kiocb(iocb)); 79 inode_unlock_shared(inode); 80 81 file_accessed(iocb->ki_filp); 82 return ret; 83 } 84 85 #ifdef CONFIG_FS_DAX 86 static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) 87 { 88 struct inode *inode = file_inode(iocb->ki_filp); 89 ssize_t ret; 90 91 if (!inode_trylock_shared(inode)) { 92 if (iocb->ki_flags & IOCB_NOWAIT) 93 return -EAGAIN; 94 inode_lock_shared(inode); 95 } 96 /* 97 * Recheck under inode lock - at this point we are sure it cannot 98 * change anymore 99 */ 100 if (!IS_DAX(inode)) { 101 inode_unlock_shared(inode); 102 /* Fallback to buffered IO in case we cannot support DAX */ 103 return generic_file_read_iter(iocb, to); 104 } 105 ret = dax_iomap_rw(iocb, to, &ext4_iomap_ops); 106 inode_unlock_shared(inode); 107 108 file_accessed(iocb->ki_filp); 109 return ret; 110 } 111 #endif 112 113 static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) 114 { 115 struct inode *inode = file_inode(iocb->ki_filp); 116 117 if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) 118 return -EIO; 119 120 if (!iov_iter_count(to)) 121 return 0; /* skip atime */ 122 123 #ifdef CONFIG_FS_DAX 124 if (IS_DAX(inode)) 125 return ext4_dax_read_iter(iocb, to); 126 #endif 127 if (iocb->ki_flags & IOCB_DIRECT) 128 return ext4_dio_read_iter(iocb, to); 129 130 return generic_file_read_iter(iocb, to); 131 } 132 133 /* 134 * Called when an inode is released. Note that this is different 135 * from ext4_file_open: open gets called at every open, but release 136 * gets called only when /all/ the files are closed. 137 */ 138 static int ext4_release_file(struct inode *inode, struct file *filp) 139 { 140 if (ext4_test_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE)) { 141 ext4_alloc_da_blocks(inode); 142 ext4_clear_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE); 143 } 144 /* if we are the last writer on the inode, drop the block reservation */ 145 if ((filp->f_mode & FMODE_WRITE) && 146 (atomic_read(&inode->i_writecount) == 1) && 147 !EXT4_I(inode)->i_reserved_data_blocks) 148 { 149 down_write(&EXT4_I(inode)->i_data_sem); 150 ext4_discard_preallocations(inode); 151 up_write(&EXT4_I(inode)->i_data_sem); 152 } 153 if (is_dx(inode) && filp->private_data) 154 ext4_htree_free_dir_info(filp->private_data); 155 156 return 0; 157 } 158 159 /* 160 * This tests whether the IO in question is block-aligned or not. 161 * Ext4 utilizes unwritten extents when hole-filling during direct IO, and they 162 * are converted to written only after the IO is complete. Until they are 163 * mapped, these blocks appear as holes, so dio_zero_block() will assume that 164 * it needs to zero out portions of the start and/or end block. If 2 AIO 165 * threads are at work on the same unwritten block, they must be synchronized 166 * or one thread will zero the other's data, causing corruption. 167 */ 168 static int 169 ext4_unaligned_aio(struct inode *inode, struct iov_iter *from, loff_t pos) 170 { 171 struct super_block *sb = inode->i_sb; 172 int blockmask = sb->s_blocksize - 1; 173 174 if (pos >= ALIGN(i_size_read(inode), sb->s_blocksize)) 175 return 0; 176 177 if ((pos | iov_iter_alignment(from)) & blockmask) 178 return 1; 179 180 return 0; 181 } 182 183 /* Is IO overwriting allocated and initialized blocks? */ 184 static bool ext4_overwrite_io(struct inode *inode, loff_t pos, loff_t len) 185 { 186 struct ext4_map_blocks map; 187 unsigned int blkbits = inode->i_blkbits; 188 int err, blklen; 189 190 if (pos + len > i_size_read(inode)) 191 return false; 192 193 map.m_lblk = pos >> blkbits; 194 map.m_len = EXT4_MAX_BLOCKS(len, pos, blkbits); 195 blklen = map.m_len; 196 197 err = ext4_map_blocks(NULL, inode, &map, 0); 198 /* 199 * 'err==len' means that all of the blocks have been preallocated, 200 * regardless of whether they have been initialized or not. To exclude 201 * unwritten extents, we need to check m_flags. 202 */ 203 return err == blklen && (map.m_flags & EXT4_MAP_MAPPED); 204 } 205 206 static ssize_t ext4_write_checks(struct kiocb *iocb, struct iov_iter *from) 207 { 208 struct inode *inode = file_inode(iocb->ki_filp); 209 ssize_t ret; 210 211 if (unlikely(IS_IMMUTABLE(inode))) 212 return -EPERM; 213 214 ret = generic_write_checks(iocb, from); 215 if (ret <= 0) 216 return ret; 217 218 /* 219 * If we have encountered a bitmap-format file, the size limit 220 * is smaller than s_maxbytes, which is for extent-mapped files. 221 */ 222 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) { 223 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 224 225 if (iocb->ki_pos >= sbi->s_bitmap_maxbytes) 226 return -EFBIG; 227 iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos); 228 } 229 230 ret = file_modified(iocb->ki_filp); 231 if (ret) 232 return ret; 233 234 return iov_iter_count(from); 235 } 236 237 static ssize_t ext4_buffered_write_iter(struct kiocb *iocb, 238 struct iov_iter *from) 239 { 240 ssize_t ret; 241 struct inode *inode = file_inode(iocb->ki_filp); 242 243 if (iocb->ki_flags & IOCB_NOWAIT) 244 return -EOPNOTSUPP; 245 246 inode_lock(inode); 247 ret = ext4_write_checks(iocb, from); 248 if (ret <= 0) 249 goto out; 250 251 current->backing_dev_info = inode_to_bdi(inode); 252 ret = generic_perform_write(iocb->ki_filp, from, iocb->ki_pos); 253 current->backing_dev_info = NULL; 254 255 out: 256 inode_unlock(inode); 257 if (likely(ret > 0)) { 258 iocb->ki_pos += ret; 259 ret = generic_write_sync(iocb, ret); 260 } 261 262 return ret; 263 } 264 265 static ssize_t ext4_handle_inode_extension(struct inode *inode, loff_t offset, 266 ssize_t written, size_t count) 267 { 268 handle_t *handle; 269 bool truncate = false; 270 u8 blkbits = inode->i_blkbits; 271 ext4_lblk_t written_blk, end_blk; 272 273 /* 274 * Note that EXT4_I(inode)->i_disksize can get extended up to 275 * inode->i_size while the I/O was running due to writeback of delalloc 276 * blocks. But, the code in ext4_iomap_alloc() is careful to use 277 * zeroed/unwritten extents if this is possible; thus we won't leave 278 * uninitialized blocks in a file even if we didn't succeed in writing 279 * as much as we intended. 280 */ 281 WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize); 282 if (offset + count <= EXT4_I(inode)->i_disksize) { 283 /* 284 * We need to ensure that the inode is removed from the orphan 285 * list if it has been added prematurely, due to writeback of 286 * delalloc blocks. 287 */ 288 if (!list_empty(&EXT4_I(inode)->i_orphan) && inode->i_nlink) { 289 handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); 290 291 if (IS_ERR(handle)) { 292 ext4_orphan_del(NULL, inode); 293 return PTR_ERR(handle); 294 } 295 296 ext4_orphan_del(handle, inode); 297 ext4_journal_stop(handle); 298 } 299 300 return written; 301 } 302 303 if (written < 0) 304 goto truncate; 305 306 handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); 307 if (IS_ERR(handle)) { 308 written = PTR_ERR(handle); 309 goto truncate; 310 } 311 312 if (ext4_update_inode_size(inode, offset + written)) 313 ext4_mark_inode_dirty(handle, inode); 314 315 /* 316 * We may need to truncate allocated but not written blocks beyond EOF. 317 */ 318 written_blk = ALIGN(offset + written, 1 << blkbits); 319 end_blk = ALIGN(offset + count, 1 << blkbits); 320 if (written_blk < end_blk && ext4_can_truncate(inode)) 321 truncate = true; 322 323 /* 324 * Remove the inode from the orphan list if it has been extended and 325 * everything went OK. 326 */ 327 if (!truncate && inode->i_nlink) 328 ext4_orphan_del(handle, inode); 329 ext4_journal_stop(handle); 330 331 if (truncate) { 332 truncate: 333 ext4_truncate_failed_write(inode); 334 /* 335 * If the truncate operation failed early, then the inode may 336 * still be on the orphan list. In that case, we need to try 337 * remove the inode from the in-memory linked list. 338 */ 339 if (inode->i_nlink) 340 ext4_orphan_del(NULL, inode); 341 } 342 343 return written; 344 } 345 346 static int ext4_dio_write_end_io(struct kiocb *iocb, ssize_t size, 347 int error, unsigned int flags) 348 { 349 loff_t offset = iocb->ki_pos; 350 struct inode *inode = file_inode(iocb->ki_filp); 351 352 if (error) 353 return error; 354 355 if (size && flags & IOMAP_DIO_UNWRITTEN) 356 return ext4_convert_unwritten_extents(NULL, inode, 357 offset, size); 358 359 return 0; 360 } 361 362 static const struct iomap_dio_ops ext4_dio_write_ops = { 363 .end_io = ext4_dio_write_end_io, 364 }; 365 366 static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from) 367 { 368 ssize_t ret; 369 size_t count; 370 loff_t offset; 371 handle_t *handle; 372 struct inode *inode = file_inode(iocb->ki_filp); 373 bool extend = false, overwrite = false, unaligned_aio = false; 374 375 if (iocb->ki_flags & IOCB_NOWAIT) { 376 if (!inode_trylock(inode)) 377 return -EAGAIN; 378 } else { 379 inode_lock(inode); 380 } 381 382 if (!ext4_dio_supported(inode)) { 383 inode_unlock(inode); 384 /* 385 * Fallback to buffered I/O if the inode does not support 386 * direct I/O. 387 */ 388 return ext4_buffered_write_iter(iocb, from); 389 } 390 391 ret = ext4_write_checks(iocb, from); 392 if (ret <= 0) { 393 inode_unlock(inode); 394 return ret; 395 } 396 397 /* 398 * Unaligned asynchronous direct I/O must be serialized among each 399 * other as the zeroing of partial blocks of two competing unaligned 400 * asynchronous direct I/O writes can result in data corruption. 401 */ 402 offset = iocb->ki_pos; 403 count = iov_iter_count(from); 404 if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) && 405 !is_sync_kiocb(iocb) && ext4_unaligned_aio(inode, from, offset)) { 406 unaligned_aio = true; 407 inode_dio_wait(inode); 408 } 409 410 /* 411 * Determine whether the I/O will overwrite allocated and initialized 412 * blocks. If so, check to see whether it is possible to take the 413 * dioread_nolock path. 414 */ 415 if (!unaligned_aio && ext4_overwrite_io(inode, offset, count) && 416 ext4_should_dioread_nolock(inode)) { 417 overwrite = true; 418 downgrade_write(&inode->i_rwsem); 419 } 420 421 if (offset + count > EXT4_I(inode)->i_disksize) { 422 handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); 423 if (IS_ERR(handle)) { 424 ret = PTR_ERR(handle); 425 goto out; 426 } 427 428 ret = ext4_orphan_add(handle, inode); 429 if (ret) { 430 ext4_journal_stop(handle); 431 goto out; 432 } 433 434 extend = true; 435 ext4_journal_stop(handle); 436 } 437 438 ret = iomap_dio_rw(iocb, from, &ext4_iomap_ops, &ext4_dio_write_ops, 439 is_sync_kiocb(iocb) || unaligned_aio || extend); 440 441 if (extend) 442 ret = ext4_handle_inode_extension(inode, offset, ret, count); 443 444 out: 445 if (overwrite) 446 inode_unlock_shared(inode); 447 else 448 inode_unlock(inode); 449 450 if (ret >= 0 && iov_iter_count(from)) { 451 ssize_t err; 452 loff_t endbyte; 453 454 offset = iocb->ki_pos; 455 err = ext4_buffered_write_iter(iocb, from); 456 if (err < 0) 457 return err; 458 459 /* 460 * We need to ensure that the pages within the page cache for 461 * the range covered by this I/O are written to disk and 462 * invalidated. This is in attempt to preserve the expected 463 * direct I/O semantics in the case we fallback to buffered I/O 464 * to complete off the I/O request. 465 */ 466 ret += err; 467 endbyte = offset + err - 1; 468 err = filemap_write_and_wait_range(iocb->ki_filp->f_mapping, 469 offset, endbyte); 470 if (!err) 471 invalidate_mapping_pages(iocb->ki_filp->f_mapping, 472 offset >> PAGE_SHIFT, 473 endbyte >> PAGE_SHIFT); 474 } 475 476 return ret; 477 } 478 479 #ifdef CONFIG_FS_DAX 480 static ssize_t 481 ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) 482 { 483 ssize_t ret; 484 size_t count; 485 loff_t offset; 486 handle_t *handle; 487 bool extend = false; 488 struct inode *inode = file_inode(iocb->ki_filp); 489 490 if (!inode_trylock(inode)) { 491 if (iocb->ki_flags & IOCB_NOWAIT) 492 return -EAGAIN; 493 inode_lock(inode); 494 } 495 496 ret = ext4_write_checks(iocb, from); 497 if (ret <= 0) 498 goto out; 499 500 offset = iocb->ki_pos; 501 count = iov_iter_count(from); 502 503 if (offset + count > EXT4_I(inode)->i_disksize) { 504 handle = ext4_journal_start(inode, EXT4_HT_INODE, 2); 505 if (IS_ERR(handle)) { 506 ret = PTR_ERR(handle); 507 goto out; 508 } 509 510 ret = ext4_orphan_add(handle, inode); 511 if (ret) { 512 ext4_journal_stop(handle); 513 goto out; 514 } 515 516 extend = true; 517 ext4_journal_stop(handle); 518 } 519 520 ret = dax_iomap_rw(iocb, from, &ext4_iomap_ops); 521 522 if (extend) 523 ret = ext4_handle_inode_extension(inode, offset, ret, count); 524 out: 525 inode_unlock(inode); 526 if (ret > 0) 527 ret = generic_write_sync(iocb, ret); 528 return ret; 529 } 530 #endif 531 532 static ssize_t 533 ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) 534 { 535 struct inode *inode = file_inode(iocb->ki_filp); 536 537 if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) 538 return -EIO; 539 540 #ifdef CONFIG_FS_DAX 541 if (IS_DAX(inode)) 542 return ext4_dax_write_iter(iocb, from); 543 #endif 544 if (iocb->ki_flags & IOCB_DIRECT) 545 return ext4_dio_write_iter(iocb, from); 546 547 return ext4_buffered_write_iter(iocb, from); 548 } 549 550 #ifdef CONFIG_FS_DAX 551 static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, 552 enum page_entry_size pe_size) 553 { 554 int error = 0; 555 vm_fault_t result; 556 int retries = 0; 557 handle_t *handle = NULL; 558 struct inode *inode = file_inode(vmf->vma->vm_file); 559 struct super_block *sb = inode->i_sb; 560 561 /* 562 * We have to distinguish real writes from writes which will result in a 563 * COW page; COW writes should *not* poke the journal (the file will not 564 * be changed). Doing so would cause unintended failures when mounted 565 * read-only. 566 * 567 * We check for VM_SHARED rather than vmf->cow_page since the latter is 568 * unset for pe_size != PE_SIZE_PTE (i.e. only in do_cow_fault); for 569 * other sizes, dax_iomap_fault will handle splitting / fallback so that 570 * we eventually come back with a COW page. 571 */ 572 bool write = (vmf->flags & FAULT_FLAG_WRITE) && 573 (vmf->vma->vm_flags & VM_SHARED); 574 pfn_t pfn; 575 576 if (write) { 577 sb_start_pagefault(sb); 578 file_update_time(vmf->vma->vm_file); 579 down_read(&EXT4_I(inode)->i_mmap_sem); 580 retry: 581 handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE, 582 EXT4_DATA_TRANS_BLOCKS(sb)); 583 if (IS_ERR(handle)) { 584 up_read(&EXT4_I(inode)->i_mmap_sem); 585 sb_end_pagefault(sb); 586 return VM_FAULT_SIGBUS; 587 } 588 } else { 589 down_read(&EXT4_I(inode)->i_mmap_sem); 590 } 591 result = dax_iomap_fault(vmf, pe_size, &pfn, &error, &ext4_iomap_ops); 592 if (write) { 593 ext4_journal_stop(handle); 594 595 if ((result & VM_FAULT_ERROR) && error == -ENOSPC && 596 ext4_should_retry_alloc(sb, &retries)) 597 goto retry; 598 /* Handling synchronous page fault? */ 599 if (result & VM_FAULT_NEEDDSYNC) 600 result = dax_finish_sync_fault(vmf, pe_size, pfn); 601 up_read(&EXT4_I(inode)->i_mmap_sem); 602 sb_end_pagefault(sb); 603 } else { 604 up_read(&EXT4_I(inode)->i_mmap_sem); 605 } 606 607 return result; 608 } 609 610 static vm_fault_t ext4_dax_fault(struct vm_fault *vmf) 611 { 612 return ext4_dax_huge_fault(vmf, PE_SIZE_PTE); 613 } 614 615 static const struct vm_operations_struct ext4_dax_vm_ops = { 616 .fault = ext4_dax_fault, 617 .huge_fault = ext4_dax_huge_fault, 618 .page_mkwrite = ext4_dax_fault, 619 .pfn_mkwrite = ext4_dax_fault, 620 }; 621 #else 622 #define ext4_dax_vm_ops ext4_file_vm_ops 623 #endif 624 625 static const struct vm_operations_struct ext4_file_vm_ops = { 626 .fault = ext4_filemap_fault, 627 .map_pages = filemap_map_pages, 628 .page_mkwrite = ext4_page_mkwrite, 629 }; 630 631 static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) 632 { 633 struct inode *inode = file->f_mapping->host; 634 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 635 struct dax_device *dax_dev = sbi->s_daxdev; 636 637 if (unlikely(ext4_forced_shutdown(sbi))) 638 return -EIO; 639 640 /* 641 * We don't support synchronous mappings for non-DAX files and 642 * for DAX files if underneath dax_device is not synchronous. 643 */ 644 if (!daxdev_mapping_supported(vma, dax_dev)) 645 return -EOPNOTSUPP; 646 647 file_accessed(file); 648 if (IS_DAX(file_inode(file))) { 649 vma->vm_ops = &ext4_dax_vm_ops; 650 vma->vm_flags |= VM_HUGEPAGE; 651 } else { 652 vma->vm_ops = &ext4_file_vm_ops; 653 } 654 return 0; 655 } 656 657 static int ext4_sample_last_mounted(struct super_block *sb, 658 struct vfsmount *mnt) 659 { 660 struct ext4_sb_info *sbi = EXT4_SB(sb); 661 struct path path; 662 char buf[64], *cp; 663 handle_t *handle; 664 int err; 665 666 if (likely(sbi->s_mount_flags & EXT4_MF_MNTDIR_SAMPLED)) 667 return 0; 668 669 if (sb_rdonly(sb) || !sb_start_intwrite_trylock(sb)) 670 return 0; 671 672 sbi->s_mount_flags |= EXT4_MF_MNTDIR_SAMPLED; 673 /* 674 * Sample where the filesystem has been mounted and 675 * store it in the superblock for sysadmin convenience 676 * when trying to sort through large numbers of block 677 * devices or filesystem images. 678 */ 679 memset(buf, 0, sizeof(buf)); 680 path.mnt = mnt; 681 path.dentry = mnt->mnt_root; 682 cp = d_path(&path, buf, sizeof(buf)); 683 err = 0; 684 if (IS_ERR(cp)) 685 goto out; 686 687 handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1); 688 err = PTR_ERR(handle); 689 if (IS_ERR(handle)) 690 goto out; 691 BUFFER_TRACE(sbi->s_sbh, "get_write_access"); 692 err = ext4_journal_get_write_access(handle, sbi->s_sbh); 693 if (err) 694 goto out_journal; 695 strlcpy(sbi->s_es->s_last_mounted, cp, 696 sizeof(sbi->s_es->s_last_mounted)); 697 ext4_handle_dirty_super(handle, sb); 698 out_journal: 699 ext4_journal_stop(handle); 700 out: 701 sb_end_intwrite(sb); 702 return err; 703 } 704 705 static int ext4_file_open(struct inode * inode, struct file * filp) 706 { 707 int ret; 708 709 if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) 710 return -EIO; 711 712 ret = ext4_sample_last_mounted(inode->i_sb, filp->f_path.mnt); 713 if (ret) 714 return ret; 715 716 ret = fscrypt_file_open(inode, filp); 717 if (ret) 718 return ret; 719 720 ret = fsverity_file_open(inode, filp); 721 if (ret) 722 return ret; 723 724 /* 725 * Set up the jbd2_inode if we are opening the inode for 726 * writing and the journal is present 727 */ 728 if (filp->f_mode & FMODE_WRITE) { 729 ret = ext4_inode_attach_jinode(inode); 730 if (ret < 0) 731 return ret; 732 } 733 734 filp->f_mode |= FMODE_NOWAIT; 735 return dquot_file_open(inode, filp); 736 } 737 738 /* 739 * ext4_llseek() handles both block-mapped and extent-mapped maxbytes values 740 * by calling generic_file_llseek_size() with the appropriate maxbytes 741 * value for each. 742 */ 743 loff_t ext4_llseek(struct file *file, loff_t offset, int whence) 744 { 745 struct inode *inode = file->f_mapping->host; 746 loff_t maxbytes; 747 748 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 749 maxbytes = EXT4_SB(inode->i_sb)->s_bitmap_maxbytes; 750 else 751 maxbytes = inode->i_sb->s_maxbytes; 752 753 switch (whence) { 754 default: 755 return generic_file_llseek_size(file, offset, whence, 756 maxbytes, i_size_read(inode)); 757 case SEEK_HOLE: 758 inode_lock_shared(inode); 759 offset = iomap_seek_hole(inode, offset, 760 &ext4_iomap_report_ops); 761 inode_unlock_shared(inode); 762 break; 763 case SEEK_DATA: 764 inode_lock_shared(inode); 765 offset = iomap_seek_data(inode, offset, 766 &ext4_iomap_report_ops); 767 inode_unlock_shared(inode); 768 break; 769 } 770 771 if (offset < 0) 772 return offset; 773 return vfs_setpos(file, offset, maxbytes); 774 } 775 776 const struct file_operations ext4_file_operations = { 777 .llseek = ext4_llseek, 778 .read_iter = ext4_file_read_iter, 779 .write_iter = ext4_file_write_iter, 780 .unlocked_ioctl = ext4_ioctl, 781 #ifdef CONFIG_COMPAT 782 .compat_ioctl = ext4_compat_ioctl, 783 #endif 784 .mmap = ext4_file_mmap, 785 .mmap_supported_flags = MAP_SYNC, 786 .open = ext4_file_open, 787 .release = ext4_release_file, 788 .fsync = ext4_sync_file, 789 .get_unmapped_area = thp_get_unmapped_area, 790 .splice_read = generic_file_splice_read, 791 .splice_write = iter_file_splice_write, 792 .fallocate = ext4_fallocate, 793 }; 794 795 const struct inode_operations ext4_file_inode_operations = { 796 .setattr = ext4_setattr, 797 .getattr = ext4_file_getattr, 798 .listxattr = ext4_listxattr, 799 .get_acl = ext4_get_acl, 800 .set_acl = ext4_set_acl, 801 .fiemap = ext4_fiemap, 802 }; 803 804