1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2010 Red Hat, Inc. 4 * Copyright (c) 2016-2021 Christoph Hellwig. 5 */ 6 #include <linux/module.h> 7 #include <linux/compiler.h> 8 #include <linux/fs.h> 9 #include <linux/pagemap.h> 10 #include <linux/iomap.h> 11 #include <linux/backing-dev.h> 12 #include <linux/uio.h> 13 #include <linux/task_io_accounting_ops.h> 14 #include "trace.h" 15 16 #include "../internal.h" 17 18 /* 19 * Private flags for iomap_dio, must not overlap with the public ones in 20 * iomap.h: 21 */ 22 #define IOMAP_DIO_WRITE_FUA (1 << 28) 23 #define IOMAP_DIO_NEED_SYNC (1 << 29) 24 #define IOMAP_DIO_WRITE (1 << 30) 25 #define IOMAP_DIO_DIRTY (1 << 31) 26 27 struct iomap_dio { 28 struct kiocb *iocb; 29 const struct iomap_dio_ops *dops; 30 loff_t i_size; 31 loff_t size; 32 atomic_t ref; 33 unsigned flags; 34 int error; 35 size_t done_before; 36 bool wait_for_completion; 37 38 union { 39 /* used during submission and for synchronous completion: */ 40 struct { 41 struct iov_iter *iter; 42 struct task_struct *waiter; 43 struct bio *poll_bio; 44 } submit; 45 46 /* used for aio completion: */ 47 struct { 48 struct work_struct work; 49 } aio; 50 }; 51 }; 52 53 static void iomap_dio_submit_bio(const struct iomap_iter *iter, 54 struct iomap_dio *dio, struct bio *bio, loff_t pos) 55 { 56 atomic_inc(&dio->ref); 57 58 if (dio->iocb->ki_flags & IOCB_HIPRI) { 59 bio_set_polled(bio, dio->iocb); 60 dio->submit.poll_bio = bio; 61 } 62 63 if (dio->dops && dio->dops->submit_io) 64 dio->dops->submit_io(iter, bio, pos); 65 else 66 submit_bio(bio); 67 } 68 69 ssize_t iomap_dio_complete(struct iomap_dio *dio) 70 { 71 const struct iomap_dio_ops *dops = dio->dops; 72 struct kiocb *iocb = dio->iocb; 73 struct inode *inode = file_inode(iocb->ki_filp); 74 loff_t offset = iocb->ki_pos; 75 ssize_t ret = dio->error; 76 77 if (dops && dops->end_io) 78 ret = dops->end_io(iocb, dio->size, ret, dio->flags); 79 80 if (likely(!ret)) { 81 ret = dio->size; 82 /* check for short read */ 83 if (offset + ret > dio->i_size && 84 !(dio->flags & IOMAP_DIO_WRITE)) 85 ret = dio->i_size - offset; 86 iocb->ki_pos += ret; 87 } 88 89 /* 90 * Try again to invalidate clean pages which might have been cached by 91 * non-direct readahead, or faulted in by get_user_pages() if the source 92 * of the write was an mmap'ed region of the file we're writing. Either 93 * one is a pretty crazy thing to do, so we don't support it 100%. If 94 * this invalidation fails, tough, the write still worked... 95 * 96 * And this page cache invalidation has to be after ->end_io(), as some 97 * filesystems convert unwritten extents to real allocations in 98 * ->end_io() when necessary, otherwise a racing buffer read would cache 99 * zeros from unwritten extents. 100 */ 101 if (!dio->error && dio->size && 102 (dio->flags & IOMAP_DIO_WRITE) && inode->i_mapping->nrpages) { 103 int err; 104 err = invalidate_inode_pages2_range(inode->i_mapping, 105 offset >> PAGE_SHIFT, 106 (offset + dio->size - 1) >> PAGE_SHIFT); 107 if (err) 108 dio_warn_stale_pagecache(iocb->ki_filp); 109 } 110 111 inode_dio_end(file_inode(iocb->ki_filp)); 112 /* 113 * If this is a DSYNC write, make sure we push it to stable storage now 114 * that we've written data. 115 */ 116 if (ret > 0 && (dio->flags & IOMAP_DIO_NEED_SYNC)) 117 ret = generic_write_sync(iocb, ret); 118 119 if (ret > 0) 120 ret += dio->done_before; 121 122 kfree(dio); 123 124 return ret; 125 } 126 EXPORT_SYMBOL_GPL(iomap_dio_complete); 127 128 static void iomap_dio_complete_work(struct work_struct *work) 129 { 130 struct iomap_dio *dio = container_of(work, struct iomap_dio, aio.work); 131 struct kiocb *iocb = dio->iocb; 132 133 iocb->ki_complete(iocb, iomap_dio_complete(dio)); 134 } 135 136 /* 137 * Set an error in the dio if none is set yet. We have to use cmpxchg 138 * as the submission context and the completion context(s) can race to 139 * update the error. 140 */ 141 static inline void iomap_dio_set_error(struct iomap_dio *dio, int ret) 142 { 143 cmpxchg(&dio->error, 0, ret); 144 } 145 146 static void iomap_dio_bio_end_io(struct bio *bio) 147 { 148 struct iomap_dio *dio = bio->bi_private; 149 bool should_dirty = (dio->flags & IOMAP_DIO_DIRTY); 150 151 if (bio->bi_status) 152 iomap_dio_set_error(dio, blk_status_to_errno(bio->bi_status)); 153 154 if (atomic_dec_and_test(&dio->ref)) { 155 if (dio->wait_for_completion) { 156 struct task_struct *waiter = dio->submit.waiter; 157 WRITE_ONCE(dio->submit.waiter, NULL); 158 blk_wake_io_task(waiter); 159 } else if (dio->flags & IOMAP_DIO_WRITE) { 160 struct inode *inode = file_inode(dio->iocb->ki_filp); 161 162 WRITE_ONCE(dio->iocb->private, NULL); 163 INIT_WORK(&dio->aio.work, iomap_dio_complete_work); 164 queue_work(inode->i_sb->s_dio_done_wq, &dio->aio.work); 165 } else { 166 WRITE_ONCE(dio->iocb->private, NULL); 167 iomap_dio_complete_work(&dio->aio.work); 168 } 169 } 170 171 if (should_dirty) { 172 bio_check_pages_dirty(bio); 173 } else { 174 bio_release_pages(bio, false); 175 bio_put(bio); 176 } 177 } 178 179 static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, 180 loff_t pos, unsigned len) 181 { 182 struct page *page = ZERO_PAGE(0); 183 int flags = REQ_SYNC | REQ_IDLE; 184 struct bio *bio; 185 186 bio = bio_alloc(GFP_KERNEL, 1); 187 bio_set_dev(bio, iter->iomap.bdev); 188 bio->bi_iter.bi_sector = iomap_sector(&iter->iomap, pos); 189 bio->bi_private = dio; 190 bio->bi_end_io = iomap_dio_bio_end_io; 191 192 get_page(page); 193 __bio_add_page(bio, page, len, 0); 194 bio_set_op_attrs(bio, REQ_OP_WRITE, flags); 195 iomap_dio_submit_bio(iter, dio, bio, pos); 196 } 197 198 /* 199 * Figure out the bio's operation flags from the dio request, the 200 * mapping, and whether or not we want FUA. Note that we can end up 201 * clearing the WRITE_FUA flag in the dio request. 202 */ 203 static inline unsigned int iomap_dio_bio_opflags(struct iomap_dio *dio, 204 const struct iomap *iomap, bool use_fua) 205 { 206 unsigned int opflags = REQ_SYNC | REQ_IDLE; 207 208 if (!(dio->flags & IOMAP_DIO_WRITE)) { 209 WARN_ON_ONCE(iomap->flags & IOMAP_F_ZONE_APPEND); 210 return REQ_OP_READ; 211 } 212 213 if (iomap->flags & IOMAP_F_ZONE_APPEND) 214 opflags |= REQ_OP_ZONE_APPEND; 215 else 216 opflags |= REQ_OP_WRITE; 217 218 if (use_fua) 219 opflags |= REQ_FUA; 220 else 221 dio->flags &= ~IOMAP_DIO_WRITE_FUA; 222 223 return opflags; 224 } 225 226 static loff_t iomap_dio_bio_iter(const struct iomap_iter *iter, 227 struct iomap_dio *dio) 228 { 229 const struct iomap *iomap = &iter->iomap; 230 struct inode *inode = iter->inode; 231 unsigned int blkbits = blksize_bits(bdev_logical_block_size(iomap->bdev)); 232 unsigned int fs_block_size = i_blocksize(inode), pad; 233 unsigned int align = iov_iter_alignment(dio->submit.iter); 234 loff_t length = iomap_length(iter); 235 loff_t pos = iter->pos; 236 unsigned int bio_opf; 237 struct bio *bio; 238 bool need_zeroout = false; 239 bool use_fua = false; 240 int nr_pages, ret = 0; 241 size_t copied = 0; 242 size_t orig_count; 243 244 if ((pos | length | align) & ((1 << blkbits) - 1)) 245 return -EINVAL; 246 247 if (iomap->type == IOMAP_UNWRITTEN) { 248 dio->flags |= IOMAP_DIO_UNWRITTEN; 249 need_zeroout = true; 250 } 251 252 if (iomap->flags & IOMAP_F_SHARED) 253 dio->flags |= IOMAP_DIO_COW; 254 255 if (iomap->flags & IOMAP_F_NEW) { 256 need_zeroout = true; 257 } else if (iomap->type == IOMAP_MAPPED) { 258 /* 259 * Use a FUA write if we need datasync semantics, this is a pure 260 * data IO that doesn't require any metadata updates (including 261 * after IO completion such as unwritten extent conversion) and 262 * the underlying device supports FUA. This allows us to avoid 263 * cache flushes on IO completion. 264 */ 265 if (!(iomap->flags & (IOMAP_F_SHARED|IOMAP_F_DIRTY)) && 266 (dio->flags & IOMAP_DIO_WRITE_FUA) && 267 blk_queue_fua(bdev_get_queue(iomap->bdev))) 268 use_fua = true; 269 } 270 271 /* 272 * Save the original count and trim the iter to just the extent we 273 * are operating on right now. The iter will be re-expanded once 274 * we are done. 275 */ 276 orig_count = iov_iter_count(dio->submit.iter); 277 iov_iter_truncate(dio->submit.iter, length); 278 279 if (!iov_iter_count(dio->submit.iter)) 280 goto out; 281 282 /* 283 * We can only poll for single bio I/Os. 284 */ 285 if (need_zeroout || 286 ((dio->flags & IOMAP_DIO_WRITE) && pos >= i_size_read(inode))) 287 dio->iocb->ki_flags &= ~IOCB_HIPRI; 288 289 if (need_zeroout) { 290 /* zero out from the start of the block to the write offset */ 291 pad = pos & (fs_block_size - 1); 292 if (pad) 293 iomap_dio_zero(iter, dio, pos - pad, pad); 294 } 295 296 /* 297 * Set the operation flags early so that bio_iov_iter_get_pages 298 * can set up the page vector appropriately for a ZONE_APPEND 299 * operation. 300 */ 301 bio_opf = iomap_dio_bio_opflags(dio, iomap, use_fua); 302 303 nr_pages = bio_iov_vecs_to_alloc(dio->submit.iter, BIO_MAX_VECS); 304 do { 305 size_t n; 306 if (dio->error) { 307 iov_iter_revert(dio->submit.iter, copied); 308 copied = ret = 0; 309 goto out; 310 } 311 312 bio = bio_alloc(GFP_KERNEL, nr_pages); 313 bio_set_dev(bio, iomap->bdev); 314 bio->bi_iter.bi_sector = iomap_sector(iomap, pos); 315 bio->bi_write_hint = dio->iocb->ki_hint; 316 bio->bi_ioprio = dio->iocb->ki_ioprio; 317 bio->bi_private = dio; 318 bio->bi_end_io = iomap_dio_bio_end_io; 319 bio->bi_opf = bio_opf; 320 321 ret = bio_iov_iter_get_pages(bio, dio->submit.iter); 322 if (unlikely(ret)) { 323 /* 324 * We have to stop part way through an IO. We must fall 325 * through to the sub-block tail zeroing here, otherwise 326 * this short IO may expose stale data in the tail of 327 * the block we haven't written data to. 328 */ 329 bio_put(bio); 330 goto zero_tail; 331 } 332 333 n = bio->bi_iter.bi_size; 334 if (dio->flags & IOMAP_DIO_WRITE) { 335 task_io_account_write(n); 336 } else { 337 if (dio->flags & IOMAP_DIO_DIRTY) 338 bio_set_pages_dirty(bio); 339 } 340 341 dio->size += n; 342 copied += n; 343 344 nr_pages = bio_iov_vecs_to_alloc(dio->submit.iter, 345 BIO_MAX_VECS); 346 /* 347 * We can only poll for single bio I/Os. 348 */ 349 if (nr_pages) 350 dio->iocb->ki_flags &= ~IOCB_HIPRI; 351 iomap_dio_submit_bio(iter, dio, bio, pos); 352 pos += n; 353 } while (nr_pages); 354 355 /* 356 * We need to zeroout the tail of a sub-block write if the extent type 357 * requires zeroing or the write extends beyond EOF. If we don't zero 358 * the block tail in the latter case, we can expose stale data via mmap 359 * reads of the EOF block. 360 */ 361 zero_tail: 362 if (need_zeroout || 363 ((dio->flags & IOMAP_DIO_WRITE) && pos >= i_size_read(inode))) { 364 /* zero out from the end of the write to the end of the block */ 365 pad = pos & (fs_block_size - 1); 366 if (pad) 367 iomap_dio_zero(iter, dio, pos, fs_block_size - pad); 368 } 369 out: 370 /* Undo iter limitation to current extent */ 371 iov_iter_reexpand(dio->submit.iter, orig_count - copied); 372 if (copied) 373 return copied; 374 return ret; 375 } 376 377 static loff_t iomap_dio_hole_iter(const struct iomap_iter *iter, 378 struct iomap_dio *dio) 379 { 380 loff_t length = iov_iter_zero(iomap_length(iter), dio->submit.iter); 381 382 dio->size += length; 383 if (!length) 384 return -EFAULT; 385 return length; 386 } 387 388 static loff_t iomap_dio_inline_iter(const struct iomap_iter *iomi, 389 struct iomap_dio *dio) 390 { 391 const struct iomap *iomap = &iomi->iomap; 392 struct iov_iter *iter = dio->submit.iter; 393 void *inline_data = iomap_inline_data(iomap, iomi->pos); 394 loff_t length = iomap_length(iomi); 395 loff_t pos = iomi->pos; 396 size_t copied; 397 398 if (WARN_ON_ONCE(!iomap_inline_data_valid(iomap))) 399 return -EIO; 400 401 if (dio->flags & IOMAP_DIO_WRITE) { 402 loff_t size = iomi->inode->i_size; 403 404 if (pos > size) 405 memset(iomap_inline_data(iomap, size), 0, pos - size); 406 copied = copy_from_iter(inline_data, length, iter); 407 if (copied) { 408 if (pos + copied > size) 409 i_size_write(iomi->inode, pos + copied); 410 mark_inode_dirty(iomi->inode); 411 } 412 } else { 413 copied = copy_to_iter(inline_data, length, iter); 414 } 415 dio->size += copied; 416 if (!copied) 417 return -EFAULT; 418 return copied; 419 } 420 421 static loff_t iomap_dio_iter(const struct iomap_iter *iter, 422 struct iomap_dio *dio) 423 { 424 switch (iter->iomap.type) { 425 case IOMAP_HOLE: 426 if (WARN_ON_ONCE(dio->flags & IOMAP_DIO_WRITE)) 427 return -EIO; 428 return iomap_dio_hole_iter(iter, dio); 429 case IOMAP_UNWRITTEN: 430 if (!(dio->flags & IOMAP_DIO_WRITE)) 431 return iomap_dio_hole_iter(iter, dio); 432 return iomap_dio_bio_iter(iter, dio); 433 case IOMAP_MAPPED: 434 return iomap_dio_bio_iter(iter, dio); 435 case IOMAP_INLINE: 436 return iomap_dio_inline_iter(iter, dio); 437 case IOMAP_DELALLOC: 438 /* 439 * DIO is not serialised against mmap() access at all, and so 440 * if the page_mkwrite occurs between the writeback and the 441 * iomap_iter() call in the DIO path, then it will see the 442 * DELALLOC block that the page-mkwrite allocated. 443 */ 444 pr_warn_ratelimited("Direct I/O collision with buffered writes! File: %pD4 Comm: %.20s\n", 445 dio->iocb->ki_filp, current->comm); 446 return -EIO; 447 default: 448 WARN_ON_ONCE(1); 449 return -EIO; 450 } 451 } 452 453 /* 454 * iomap_dio_rw() always completes O_[D]SYNC writes regardless of whether the IO 455 * is being issued as AIO or not. This allows us to optimise pure data writes 456 * to use REQ_FUA rather than requiring generic_write_sync() to issue a 457 * REQ_FLUSH post write. This is slightly tricky because a single request here 458 * can be mapped into multiple disjoint IOs and only a subset of the IOs issued 459 * may be pure data writes. In that case, we still need to do a full data sync 460 * completion. 461 * 462 * When page faults are disabled and @dio_flags includes IOMAP_DIO_PARTIAL, 463 * __iomap_dio_rw can return a partial result if it encounters a non-resident 464 * page in @iter after preparing a transfer. In that case, the non-resident 465 * pages can be faulted in and the request resumed with @done_before set to the 466 * number of bytes previously transferred. The request will then complete with 467 * the correct total number of bytes transferred; this is essential for 468 * completing partial requests asynchronously. 469 * 470 * Returns -ENOTBLK In case of a page invalidation invalidation failure for 471 * writes. The callers needs to fall back to buffered I/O in this case. 472 */ 473 struct iomap_dio * 474 __iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, 475 const struct iomap_ops *ops, const struct iomap_dio_ops *dops, 476 unsigned int dio_flags, size_t done_before) 477 { 478 struct address_space *mapping = iocb->ki_filp->f_mapping; 479 struct inode *inode = file_inode(iocb->ki_filp); 480 struct iomap_iter iomi = { 481 .inode = inode, 482 .pos = iocb->ki_pos, 483 .len = iov_iter_count(iter), 484 .flags = IOMAP_DIRECT, 485 }; 486 loff_t end = iomi.pos + iomi.len - 1, ret = 0; 487 bool wait_for_completion = 488 is_sync_kiocb(iocb) || (dio_flags & IOMAP_DIO_FORCE_WAIT); 489 struct blk_plug plug; 490 struct iomap_dio *dio; 491 492 if (!iomi.len) 493 return NULL; 494 495 dio = kmalloc(sizeof(*dio), GFP_KERNEL); 496 if (!dio) 497 return ERR_PTR(-ENOMEM); 498 499 dio->iocb = iocb; 500 atomic_set(&dio->ref, 1); 501 dio->size = 0; 502 dio->i_size = i_size_read(inode); 503 dio->dops = dops; 504 dio->error = 0; 505 dio->flags = 0; 506 dio->done_before = done_before; 507 508 dio->submit.iter = iter; 509 dio->submit.waiter = current; 510 dio->submit.poll_bio = NULL; 511 512 if (iov_iter_rw(iter) == READ) { 513 if (iomi.pos >= dio->i_size) 514 goto out_free_dio; 515 516 if (iocb->ki_flags & IOCB_NOWAIT) { 517 if (filemap_range_needs_writeback(mapping, iomi.pos, 518 end)) { 519 ret = -EAGAIN; 520 goto out_free_dio; 521 } 522 iomi.flags |= IOMAP_NOWAIT; 523 } 524 525 if (iter_is_iovec(iter)) 526 dio->flags |= IOMAP_DIO_DIRTY; 527 } else { 528 iomi.flags |= IOMAP_WRITE; 529 dio->flags |= IOMAP_DIO_WRITE; 530 531 if (iocb->ki_flags & IOCB_NOWAIT) { 532 if (filemap_range_has_page(mapping, iomi.pos, end)) { 533 ret = -EAGAIN; 534 goto out_free_dio; 535 } 536 iomi.flags |= IOMAP_NOWAIT; 537 } 538 539 /* for data sync or sync, we need sync completion processing */ 540 if (iocb->ki_flags & IOCB_DSYNC) 541 dio->flags |= IOMAP_DIO_NEED_SYNC; 542 543 /* 544 * For datasync only writes, we optimistically try using FUA for 545 * this IO. Any non-FUA write that occurs will clear this flag, 546 * hence we know before completion whether a cache flush is 547 * necessary. 548 */ 549 if ((iocb->ki_flags & (IOCB_DSYNC | IOCB_SYNC)) == IOCB_DSYNC) 550 dio->flags |= IOMAP_DIO_WRITE_FUA; 551 } 552 553 if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) { 554 ret = -EAGAIN; 555 if (iomi.pos >= dio->i_size || 556 iomi.pos + iomi.len > dio->i_size) 557 goto out_free_dio; 558 iomi.flags |= IOMAP_OVERWRITE_ONLY; 559 } 560 561 ret = filemap_write_and_wait_range(mapping, iomi.pos, end); 562 if (ret) 563 goto out_free_dio; 564 565 if (iov_iter_rw(iter) == WRITE) { 566 /* 567 * Try to invalidate cache pages for the range we are writing. 568 * If this invalidation fails, let the caller fall back to 569 * buffered I/O. 570 */ 571 if (invalidate_inode_pages2_range(mapping, 572 iomi.pos >> PAGE_SHIFT, end >> PAGE_SHIFT)) { 573 trace_iomap_dio_invalidate_fail(inode, iomi.pos, 574 iomi.len); 575 ret = -ENOTBLK; 576 goto out_free_dio; 577 } 578 579 if (!wait_for_completion && !inode->i_sb->s_dio_done_wq) { 580 ret = sb_init_dio_done_wq(inode->i_sb); 581 if (ret < 0) 582 goto out_free_dio; 583 } 584 } 585 586 inode_dio_begin(inode); 587 588 blk_start_plug(&plug); 589 while ((ret = iomap_iter(&iomi, ops)) > 0) { 590 iomi.processed = iomap_dio_iter(&iomi, dio); 591 592 /* 593 * We can only poll for single bio I/Os. 594 */ 595 iocb->ki_flags &= ~IOCB_HIPRI; 596 } 597 598 blk_finish_plug(&plug); 599 600 /* 601 * We only report that we've read data up to i_size. 602 * Revert iter to a state corresponding to that as some callers (such 603 * as the splice code) rely on it. 604 */ 605 if (iov_iter_rw(iter) == READ && iomi.pos >= dio->i_size) 606 iov_iter_revert(iter, iomi.pos - dio->i_size); 607 608 if (ret == -EFAULT && dio->size && (dio_flags & IOMAP_DIO_PARTIAL)) { 609 if (!(iocb->ki_flags & IOCB_NOWAIT)) 610 wait_for_completion = true; 611 ret = 0; 612 } 613 614 /* magic error code to fall back to buffered I/O */ 615 if (ret == -ENOTBLK) { 616 wait_for_completion = true; 617 ret = 0; 618 } 619 if (ret < 0) 620 iomap_dio_set_error(dio, ret); 621 622 /* 623 * If all the writes we issued were FUA, we don't need to flush the 624 * cache on IO completion. Clear the sync flag for this case. 625 */ 626 if (dio->flags & IOMAP_DIO_WRITE_FUA) 627 dio->flags &= ~IOMAP_DIO_NEED_SYNC; 628 629 WRITE_ONCE(iocb->private, dio->submit.poll_bio); 630 631 /* 632 * We are about to drop our additional submission reference, which 633 * might be the last reference to the dio. There are three different 634 * ways we can progress here: 635 * 636 * (a) If this is the last reference we will always complete and free 637 * the dio ourselves. 638 * (b) If this is not the last reference, and we serve an asynchronous 639 * iocb, we must never touch the dio after the decrement, the 640 * I/O completion handler will complete and free it. 641 * (c) If this is not the last reference, but we serve a synchronous 642 * iocb, the I/O completion handler will wake us up on the drop 643 * of the final reference, and we will complete and free it here 644 * after we got woken by the I/O completion handler. 645 */ 646 dio->wait_for_completion = wait_for_completion; 647 if (!atomic_dec_and_test(&dio->ref)) { 648 if (!wait_for_completion) 649 return ERR_PTR(-EIOCBQUEUED); 650 651 for (;;) { 652 set_current_state(TASK_UNINTERRUPTIBLE); 653 if (!READ_ONCE(dio->submit.waiter)) 654 break; 655 656 if (!dio->submit.poll_bio || 657 !bio_poll(dio->submit.poll_bio, NULL, 0)) 658 blk_io_schedule(); 659 } 660 __set_current_state(TASK_RUNNING); 661 } 662 663 return dio; 664 665 out_free_dio: 666 kfree(dio); 667 if (ret) 668 return ERR_PTR(ret); 669 return NULL; 670 } 671 EXPORT_SYMBOL_GPL(__iomap_dio_rw); 672 673 ssize_t 674 iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, 675 const struct iomap_ops *ops, const struct iomap_dio_ops *dops, 676 unsigned int dio_flags, size_t done_before) 677 { 678 struct iomap_dio *dio; 679 680 dio = __iomap_dio_rw(iocb, iter, ops, dops, dio_flags, done_before); 681 if (IS_ERR_OR_NULL(dio)) 682 return PTR_ERR_OR_ZERO(dio); 683 return iomap_dio_complete(dio); 684 } 685 EXPORT_SYMBOL_GPL(iomap_dio_rw); 686