1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * linux/fs/nfs/write.c 4 * 5 * Write file data over NFS. 6 * 7 * Copyright (C) 1996, 1997, Olaf Kirch <okir@monad.swb.de> 8 */ 9 10#include <linux/types.h> 11#include <linux/slab.h> 12#include <linux/mm.h> 13#include <linux/pagemap.h> 14#include <linux/file.h> 15#include <linux/writeback.h> 16#include <linux/swap.h> 17#include <linux/migrate.h> 18 19#include <linux/sunrpc/clnt.h> 20#include <linux/nfs_fs.h> 21#include <linux/nfs_mount.h> 22#include <linux/nfs_page.h> 23#include <linux/backing-dev.h> 24#include <linux/export.h> 25#include <linux/freezer.h> 26#include <linux/wait.h> 27#include <linux/iversion.h> 28#include <linux/filelock.h> 29 30#include <linux/uaccess.h> 31#include <linux/sched/mm.h> 32 33#include "delegation.h" 34#include "internal.h" 35#include "iostat.h" 36#include "nfs4_fs.h" 37#include "fscache.h" 38#include "pnfs.h" 39 40#include "nfstrace.h" 41 42#define NFSDBG_FACILITY NFSDBG_PAGECACHE 43 44#define MIN_POOL_WRITE (32) 45#define MIN_POOL_COMMIT (4) 46 47struct nfs_io_completion { 48 void (*complete)(void *data); 49 void *data; 50 struct kref refcount; 51}; 52 53/* 54 * Local function declarations 55 */ 56static void nfs_redirty_request(struct nfs_page *req); 57static const struct rpc_call_ops nfs_commit_ops; 58static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops; 59static const struct nfs_commit_completion_ops nfs_commit_completion_ops; 60static const struct nfs_rw_ops nfs_rw_write_ops; 61static void nfs_inode_remove_request(struct nfs_page *req); 62static void nfs_clear_request_commit(struct nfs_commit_info *cinfo, 63 struct nfs_page *req); 64static void nfs_init_cinfo_from_inode(struct nfs_commit_info *cinfo, 65 struct inode *inode); 66static struct nfs_page * 67nfs_page_search_commits_for_head_request_locked(struct nfs_inode *nfsi, 68 struct folio *folio); 69 70static struct kmem_cache *nfs_wdata_cachep; 71static mempool_t *nfs_wdata_mempool; 72static struct kmem_cache *nfs_cdata_cachep; 73static mempool_t *nfs_commit_mempool; 74 75struct nfs_commit_data *nfs_commitdata_alloc(void) 76{ 77 struct nfs_commit_data *p; 78 79 p = kmem_cache_zalloc(nfs_cdata_cachep, nfs_io_gfp_mask()); 80 if (!p) { 81 p = mempool_alloc(nfs_commit_mempool, GFP_NOWAIT); 82 if (!p) 83 return NULL; 84 memset(p, 0, sizeof(*p)); 85 } 86 INIT_LIST_HEAD(&p->pages); 87 return p; 88} 89EXPORT_SYMBOL_GPL(nfs_commitdata_alloc); 90 91void nfs_commit_free(struct nfs_commit_data *p) 92{ 93 mempool_free(p, nfs_commit_mempool); 94} 95EXPORT_SYMBOL_GPL(nfs_commit_free); 96 97static struct nfs_pgio_header *nfs_writehdr_alloc(void) 98{ 99 struct nfs_pgio_header *p; 100 101 p = kmem_cache_zalloc(nfs_wdata_cachep, nfs_io_gfp_mask()); 102 if (!p) { 103 p = mempool_alloc(nfs_wdata_mempool, GFP_NOWAIT); 104 if (!p) 105 return NULL; 106 memset(p, 0, sizeof(*p)); 107 } 108 p->rw_mode = FMODE_WRITE; 109 return p; 110} 111 112static void nfs_writehdr_free(struct nfs_pgio_header *hdr) 113{ 114 mempool_free(hdr, nfs_wdata_mempool); 115} 116 117static struct nfs_io_completion *nfs_io_completion_alloc(gfp_t gfp_flags) 118{ 119 return kmalloc(sizeof(struct nfs_io_completion), gfp_flags); 120} 121 122static void nfs_io_completion_init(struct nfs_io_completion *ioc, 123 void (*complete)(void *), void *data) 124{ 125 ioc->complete = complete; 126 ioc->data = data; 127 kref_init(&ioc->refcount); 128} 129 130static void nfs_io_completion_release(struct kref *kref) 131{ 132 struct nfs_io_completion *ioc = container_of(kref, 133 struct nfs_io_completion, refcount); 134 ioc->complete(ioc->data); 135 kfree(ioc); 136} 137 138static void nfs_io_completion_get(struct nfs_io_completion *ioc) 139{ 140 if (ioc != NULL) 141 kref_get(&ioc->refcount); 142} 143 144static void nfs_io_completion_put(struct nfs_io_completion *ioc) 145{ 146 if (ioc != NULL) 147 kref_put(&ioc->refcount, nfs_io_completion_release); 148} 149 150static void 151nfs_page_set_inode_ref(struct nfs_page *req, struct inode *inode) 152{ 153 if (!test_and_set_bit(PG_INODE_REF, &req->wb_flags)) { 154 kref_get(&req->wb_kref); 155 atomic_long_inc(&NFS_I(inode)->nrequests); 156 } 157} 158 159static int 160nfs_cancel_remove_inode(struct nfs_page *req, struct inode *inode) 161{ 162 int ret; 163 164 if (!test_bit(PG_REMOVE, &req->wb_flags)) 165 return 0; 166 ret = nfs_page_group_lock(req); 167 if (ret) 168 return ret; 169 if (test_and_clear_bit(PG_REMOVE, &req->wb_flags)) 170 nfs_page_set_inode_ref(req, inode); 171 nfs_page_group_unlock(req); 172 return 0; 173} 174 175static struct nfs_page *nfs_folio_private_request(struct folio *folio) 176{ 177 return folio_get_private(folio); 178} 179 180/** 181 * nfs_folio_find_private_request - find head request associated with a folio 182 * @folio: pointer to folio 183 * 184 * must be called while holding the inode lock. 185 * 186 * returns matching head request with reference held, or NULL if not found. 187 */ 188static struct nfs_page *nfs_folio_find_private_request(struct folio *folio) 189{ 190 struct address_space *mapping = folio_file_mapping(folio); 191 struct nfs_page *req; 192 193 if (!folio_test_private(folio)) 194 return NULL; 195 spin_lock(&mapping->i_private_lock); 196 req = nfs_folio_private_request(folio); 197 if (req) { 198 WARN_ON_ONCE(req->wb_head != req); 199 kref_get(&req->wb_kref); 200 } 201 spin_unlock(&mapping->i_private_lock); 202 return req; 203} 204 205static struct nfs_page *nfs_folio_find_swap_request(struct folio *folio) 206{ 207 struct inode *inode = folio_file_mapping(folio)->host; 208 struct nfs_inode *nfsi = NFS_I(inode); 209 struct nfs_page *req = NULL; 210 if (!folio_test_swapcache(folio)) 211 return NULL; 212 mutex_lock(&nfsi->commit_mutex); 213 if (folio_test_swapcache(folio)) { 214 req = nfs_page_search_commits_for_head_request_locked(nfsi, 215 folio); 216 if (req) { 217 WARN_ON_ONCE(req->wb_head != req); 218 kref_get(&req->wb_kref); 219 } 220 } 221 mutex_unlock(&nfsi->commit_mutex); 222 return req; 223} 224 225/** 226 * nfs_folio_find_head_request - find head request associated with a folio 227 * @folio: pointer to folio 228 * 229 * returns matching head request with reference held, or NULL if not found. 230 */ 231static struct nfs_page *nfs_folio_find_head_request(struct folio *folio) 232{ 233 struct nfs_page *req; 234 235 req = nfs_folio_find_private_request(folio); 236 if (!req) 237 req = nfs_folio_find_swap_request(folio); 238 return req; 239} 240 241static struct nfs_page *nfs_folio_find_and_lock_request(struct folio *folio) 242{ 243 struct inode *inode = folio_file_mapping(folio)->host; 244 struct nfs_page *req, *head; 245 int ret; 246 247 for (;;) { 248 req = nfs_folio_find_head_request(folio); 249 if (!req) 250 return req; 251 head = nfs_page_group_lock_head(req); 252 if (head != req) 253 nfs_release_request(req); 254 if (IS_ERR(head)) 255 return head; 256 ret = nfs_cancel_remove_inode(head, inode); 257 if (ret < 0) { 258 nfs_unlock_and_release_request(head); 259 return ERR_PTR(ret); 260 } 261 /* Ensure that nobody removed the request before we locked it */ 262 if (head == nfs_folio_private_request(folio)) 263 break; 264 if (folio_test_swapcache(folio)) 265 break; 266 nfs_unlock_and_release_request(head); 267 } 268 return head; 269} 270 271/* Adjust the file length if we're writing beyond the end */ 272static void nfs_grow_file(struct folio *folio, unsigned int offset, 273 unsigned int count) 274{ 275 struct inode *inode = folio_file_mapping(folio)->host; 276 loff_t end, i_size; 277 pgoff_t end_index; 278 279 spin_lock(&inode->i_lock); 280 i_size = i_size_read(inode); 281 end_index = ((i_size - 1) >> folio_shift(folio)) << folio_order(folio); 282 if (i_size > 0 && folio_index(folio) < end_index) 283 goto out; 284 end = folio_file_pos(folio) + (loff_t)offset + (loff_t)count; 285 if (i_size >= end) 286 goto out; 287 trace_nfs_size_grow(inode, end); 288 i_size_write(inode, end); 289 NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_SIZE; 290 nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); 291out: 292 spin_unlock(&inode->i_lock); 293 nfs_fscache_invalidate(inode, 0); 294} 295 296/* A writeback failed: mark the page as bad, and invalidate the page cache */ 297static void nfs_set_pageerror(struct address_space *mapping) 298{ 299 struct inode *inode = mapping->host; 300 301 nfs_zap_mapping(mapping->host, mapping); 302 /* Force file size revalidation */ 303 spin_lock(&inode->i_lock); 304 nfs_set_cache_invalid(inode, NFS_INO_REVAL_FORCED | 305 NFS_INO_INVALID_CHANGE | 306 NFS_INO_INVALID_SIZE); 307 spin_unlock(&inode->i_lock); 308} 309 310static void nfs_mapping_set_error(struct folio *folio, int error) 311{ 312 struct address_space *mapping = folio_file_mapping(folio); 313 314 folio_set_error(folio); 315 filemap_set_wb_err(mapping, error); 316 if (mapping->host) 317 errseq_set(&mapping->host->i_sb->s_wb_err, 318 error == -ENOSPC ? -ENOSPC : -EIO); 319 nfs_set_pageerror(mapping); 320} 321 322/* 323 * nfs_page_group_search_locked 324 * @head - head request of page group 325 * @page_offset - offset into page 326 * 327 * Search page group with head @head to find a request that contains the 328 * page offset @page_offset. 329 * 330 * Returns a pointer to the first matching nfs request, or NULL if no 331 * match is found. 332 * 333 * Must be called with the page group lock held 334 */ 335static struct nfs_page * 336nfs_page_group_search_locked(struct nfs_page *head, unsigned int page_offset) 337{ 338 struct nfs_page *req; 339 340 req = head; 341 do { 342 if (page_offset >= req->wb_pgbase && 343 page_offset < (req->wb_pgbase + req->wb_bytes)) 344 return req; 345 346 req = req->wb_this_page; 347 } while (req != head); 348 349 return NULL; 350} 351 352/* 353 * nfs_page_group_covers_page 354 * @head - head request of page group 355 * 356 * Return true if the page group with head @head covers the whole page, 357 * returns false otherwise 358 */ 359static bool nfs_page_group_covers_page(struct nfs_page *req) 360{ 361 unsigned int len = nfs_folio_length(nfs_page_to_folio(req)); 362 struct nfs_page *tmp; 363 unsigned int pos = 0; 364 365 nfs_page_group_lock(req); 366 367 for (;;) { 368 tmp = nfs_page_group_search_locked(req->wb_head, pos); 369 if (!tmp) 370 break; 371 pos = tmp->wb_pgbase + tmp->wb_bytes; 372 } 373 374 nfs_page_group_unlock(req); 375 return pos >= len; 376} 377 378/* We can set the PG_uptodate flag if we see that a write request 379 * covers the full page. 380 */ 381static void nfs_mark_uptodate(struct nfs_page *req) 382{ 383 struct folio *folio = nfs_page_to_folio(req); 384 385 if (folio_test_uptodate(folio)) 386 return; 387 if (!nfs_page_group_covers_page(req)) 388 return; 389 folio_mark_uptodate(folio); 390} 391 392static int wb_priority(struct writeback_control *wbc) 393{ 394 int ret = 0; 395 396 if (wbc->sync_mode == WB_SYNC_ALL) 397 ret = FLUSH_COND_STABLE; 398 return ret; 399} 400 401/* 402 * NFS congestion control 403 */ 404 405int nfs_congestion_kb; 406 407#define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10)) 408#define NFS_CONGESTION_OFF_THRESH \ 409 (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2)) 410 411static void nfs_folio_set_writeback(struct folio *folio) 412{ 413 struct nfs_server *nfss = NFS_SERVER(folio_file_mapping(folio)->host); 414 415 folio_start_writeback(folio); 416 if (atomic_long_inc_return(&nfss->writeback) > NFS_CONGESTION_ON_THRESH) 417 nfss->write_congested = 1; 418} 419 420static void nfs_folio_end_writeback(struct folio *folio) 421{ 422 struct nfs_server *nfss = NFS_SERVER(folio_file_mapping(folio)->host); 423 424 folio_end_writeback(folio); 425 if (atomic_long_dec_return(&nfss->writeback) < 426 NFS_CONGESTION_OFF_THRESH) 427 nfss->write_congested = 0; 428} 429 430static void nfs_page_end_writeback(struct nfs_page *req) 431{ 432 if (nfs_page_group_sync_on_bit(req, PG_WB_END)) { 433 nfs_unlock_request(req); 434 nfs_folio_end_writeback(nfs_page_to_folio(req)); 435 } else 436 nfs_unlock_request(req); 437} 438 439/* 440 * nfs_destroy_unlinked_subrequests - destroy recently unlinked subrequests 441 * 442 * @destroy_list - request list (using wb_this_page) terminated by @old_head 443 * @old_head - the old head of the list 444 * 445 * All subrequests must be locked and removed from all lists, so at this point 446 * they are only "active" in this function, and possibly in nfs_wait_on_request 447 * with a reference held by some other context. 448 */ 449static void 450nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list, 451 struct nfs_page *old_head, 452 struct inode *inode) 453{ 454 while (destroy_list) { 455 struct nfs_page *subreq = destroy_list; 456 457 destroy_list = (subreq->wb_this_page == old_head) ? 458 NULL : subreq->wb_this_page; 459 460 /* Note: lock subreq in order to change subreq->wb_head */ 461 nfs_page_set_headlock(subreq); 462 WARN_ON_ONCE(old_head != subreq->wb_head); 463 464 /* make sure old group is not used */ 465 subreq->wb_this_page = subreq; 466 subreq->wb_head = subreq; 467 468 clear_bit(PG_REMOVE, &subreq->wb_flags); 469 470 /* Note: races with nfs_page_group_destroy() */ 471 if (!kref_read(&subreq->wb_kref)) { 472 /* Check if we raced with nfs_page_group_destroy() */ 473 if (test_and_clear_bit(PG_TEARDOWN, &subreq->wb_flags)) { 474 nfs_page_clear_headlock(subreq); 475 nfs_free_request(subreq); 476 } else 477 nfs_page_clear_headlock(subreq); 478 continue; 479 } 480 nfs_page_clear_headlock(subreq); 481 482 nfs_release_request(old_head); 483 484 if (test_and_clear_bit(PG_INODE_REF, &subreq->wb_flags)) { 485 nfs_release_request(subreq); 486 atomic_long_dec(&NFS_I(inode)->nrequests); 487 } 488 489 /* subreq is now totally disconnected from page group or any 490 * write / commit lists. last chance to wake any waiters */ 491 nfs_unlock_and_release_request(subreq); 492 } 493} 494 495/* 496 * nfs_join_page_group - destroy subrequests of the head req 497 * @head: the page used to lookup the "page group" of nfs_page structures 498 * @inode: Inode to which the request belongs. 499 * 500 * This function joins all sub requests to the head request by first 501 * locking all requests in the group, cancelling any pending operations 502 * and finally updating the head request to cover the whole range covered by 503 * the (former) group. All subrequests are removed from any write or commit 504 * lists, unlinked from the group and destroyed. 505 */ 506void nfs_join_page_group(struct nfs_page *head, struct nfs_commit_info *cinfo, 507 struct inode *inode) 508{ 509 struct nfs_page *subreq; 510 struct nfs_page *destroy_list = NULL; 511 unsigned int pgbase, off, bytes; 512 513 pgbase = head->wb_pgbase; 514 bytes = head->wb_bytes; 515 off = head->wb_offset; 516 for (subreq = head->wb_this_page; subreq != head; 517 subreq = subreq->wb_this_page) { 518 /* Subrequests should always form a contiguous range */ 519 if (pgbase > subreq->wb_pgbase) { 520 off -= pgbase - subreq->wb_pgbase; 521 bytes += pgbase - subreq->wb_pgbase; 522 pgbase = subreq->wb_pgbase; 523 } 524 bytes = max(subreq->wb_pgbase + subreq->wb_bytes 525 - pgbase, bytes); 526 } 527 528 /* Set the head request's range to cover the former page group */ 529 head->wb_pgbase = pgbase; 530 head->wb_bytes = bytes; 531 head->wb_offset = off; 532 533 /* Now that all requests are locked, make sure they aren't on any list. 534 * Commit list removal accounting is done after locks are dropped */ 535 subreq = head; 536 do { 537 nfs_clear_request_commit(cinfo, subreq); 538 subreq = subreq->wb_this_page; 539 } while (subreq != head); 540 541 /* unlink subrequests from head, destroy them later */ 542 if (head->wb_this_page != head) { 543 /* destroy list will be terminated by head */ 544 destroy_list = head->wb_this_page; 545 head->wb_this_page = head; 546 } 547 548 nfs_destroy_unlinked_subrequests(destroy_list, head, inode); 549} 550 551/* 552 * nfs_lock_and_join_requests - join all subreqs to the head req 553 * @folio: the folio used to lookup the "page group" of nfs_page structures 554 * 555 * This function joins all sub requests to the head request by first 556 * locking all requests in the group, cancelling any pending operations 557 * and finally updating the head request to cover the whole range covered by 558 * the (former) group. All subrequests are removed from any write or commit 559 * lists, unlinked from the group and destroyed. 560 * 561 * Returns a locked, referenced pointer to the head request - which after 562 * this call is guaranteed to be the only request associated with the page. 563 * Returns NULL if no requests are found for @folio, or a ERR_PTR if an 564 * error was encountered. 565 */ 566static struct nfs_page *nfs_lock_and_join_requests(struct folio *folio) 567{ 568 struct inode *inode = folio_file_mapping(folio)->host; 569 struct nfs_page *head; 570 struct nfs_commit_info cinfo; 571 int ret; 572 573 nfs_init_cinfo_from_inode(&cinfo, inode); 574 /* 575 * A reference is taken only on the head request which acts as a 576 * reference to the whole page group - the group will not be destroyed 577 * until the head reference is released. 578 */ 579 head = nfs_folio_find_and_lock_request(folio); 580 if (IS_ERR_OR_NULL(head)) 581 return head; 582 583 /* lock each request in the page group */ 584 ret = nfs_page_group_lock_subrequests(head); 585 if (ret < 0) { 586 nfs_unlock_and_release_request(head); 587 return ERR_PTR(ret); 588 } 589 590 nfs_join_page_group(head, &cinfo, inode); 591 592 return head; 593} 594 595static void nfs_write_error(struct nfs_page *req, int error) 596{ 597 trace_nfs_write_error(nfs_page_to_inode(req), req, error); 598 nfs_mapping_set_error(nfs_page_to_folio(req), error); 599 nfs_inode_remove_request(req); 600 nfs_page_end_writeback(req); 601 nfs_release_request(req); 602} 603 604/* 605 * Find an associated nfs write request, and prepare to flush it out 606 * May return an error if the user signalled nfs_wait_on_request(). 607 */ 608static int nfs_page_async_flush(struct folio *folio, 609 struct writeback_control *wbc, 610 struct nfs_pageio_descriptor *pgio) 611{ 612 struct nfs_page *req; 613 int ret = 0; 614 615 req = nfs_lock_and_join_requests(folio); 616 if (!req) 617 goto out; 618 ret = PTR_ERR(req); 619 if (IS_ERR(req)) 620 goto out; 621 622 nfs_folio_set_writeback(folio); 623 WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags)); 624 625 /* If there is a fatal error that covers this write, just exit */ 626 ret = pgio->pg_error; 627 if (nfs_error_is_fatal_on_server(ret)) 628 goto out_launder; 629 630 ret = 0; 631 if (!nfs_pageio_add_request(pgio, req)) { 632 ret = pgio->pg_error; 633 /* 634 * Remove the problematic req upon fatal errors on the server 635 */ 636 if (nfs_error_is_fatal_on_server(ret)) 637 goto out_launder; 638 if (wbc->sync_mode == WB_SYNC_NONE) 639 ret = AOP_WRITEPAGE_ACTIVATE; 640 folio_redirty_for_writepage(wbc, folio); 641 nfs_redirty_request(req); 642 pgio->pg_error = 0; 643 } else 644 nfs_add_stats(folio_file_mapping(folio)->host, 645 NFSIOS_WRITEPAGES, 1); 646out: 647 return ret; 648out_launder: 649 nfs_write_error(req, ret); 650 return 0; 651} 652 653static int nfs_do_writepage(struct folio *folio, struct writeback_control *wbc, 654 struct nfs_pageio_descriptor *pgio) 655{ 656 nfs_pageio_cond_complete(pgio, folio_index(folio)); 657 return nfs_page_async_flush(folio, wbc, pgio); 658} 659 660/* 661 * Write an mmapped page to the server. 662 */ 663static int nfs_writepage_locked(struct folio *folio, 664 struct writeback_control *wbc) 665{ 666 struct nfs_pageio_descriptor pgio; 667 struct inode *inode = folio_file_mapping(folio)->host; 668 int err; 669 670 nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); 671 nfs_pageio_init_write(&pgio, inode, 0, false, 672 &nfs_async_write_completion_ops); 673 err = nfs_do_writepage(folio, wbc, &pgio); 674 pgio.pg_error = 0; 675 nfs_pageio_complete(&pgio); 676 return err; 677} 678 679static int nfs_writepages_callback(struct folio *folio, 680 struct writeback_control *wbc, void *data) 681{ 682 int ret; 683 684 ret = nfs_do_writepage(folio, wbc, data); 685 if (ret != AOP_WRITEPAGE_ACTIVATE) 686 folio_unlock(folio); 687 return ret; 688} 689 690static void nfs_io_completion_commit(void *inode) 691{ 692 nfs_commit_inode(inode, 0); 693} 694 695int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) 696{ 697 struct inode *inode = mapping->host; 698 struct nfs_pageio_descriptor pgio; 699 struct nfs_io_completion *ioc = NULL; 700 unsigned int mntflags = NFS_SERVER(inode)->flags; 701 int priority = 0; 702 int err; 703 704 if (wbc->sync_mode == WB_SYNC_NONE && 705 NFS_SERVER(inode)->write_congested) 706 return 0; 707 708 nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); 709 710 if (!(mntflags & NFS_MOUNT_WRITE_EAGER) || wbc->for_kupdate || 711 wbc->for_background || wbc->for_sync || wbc->for_reclaim) { 712 ioc = nfs_io_completion_alloc(GFP_KERNEL); 713 if (ioc) 714 nfs_io_completion_init(ioc, nfs_io_completion_commit, 715 inode); 716 priority = wb_priority(wbc); 717 } 718 719 do { 720 nfs_pageio_init_write(&pgio, inode, priority, false, 721 &nfs_async_write_completion_ops); 722 pgio.pg_io_completion = ioc; 723 err = write_cache_pages(mapping, wbc, nfs_writepages_callback, 724 &pgio); 725 pgio.pg_error = 0; 726 nfs_pageio_complete(&pgio); 727 if (err == -EAGAIN && mntflags & NFS_MOUNT_SOFTERR) 728 break; 729 } while (err < 0 && !nfs_error_is_fatal(err)); 730 nfs_io_completion_put(ioc); 731 732 if (err < 0) 733 goto out_err; 734 return 0; 735out_err: 736 return err; 737} 738 739/* 740 * Insert a write request into an inode 741 */ 742static void nfs_inode_add_request(struct nfs_page *req) 743{ 744 struct folio *folio = nfs_page_to_folio(req); 745 struct address_space *mapping = folio_file_mapping(folio); 746 struct nfs_inode *nfsi = NFS_I(mapping->host); 747 748 WARN_ON_ONCE(req->wb_this_page != req); 749 750 /* Lock the request! */ 751 nfs_lock_request(req); 752 753 /* 754 * Swap-space should not get truncated. Hence no need to plug the race 755 * with invalidate/truncate. 756 */ 757 spin_lock(&mapping->i_private_lock); 758 if (likely(!folio_test_swapcache(folio))) { 759 set_bit(PG_MAPPED, &req->wb_flags); 760 folio_set_private(folio); 761 folio->private = req; 762 } 763 spin_unlock(&mapping->i_private_lock); 764 atomic_long_inc(&nfsi->nrequests); 765 /* this a head request for a page group - mark it as having an 766 * extra reference so sub groups can follow suit. 767 * This flag also informs pgio layer when to bump nrequests when 768 * adding subrequests. */ 769 WARN_ON(test_and_set_bit(PG_INODE_REF, &req->wb_flags)); 770 kref_get(&req->wb_kref); 771} 772 773/* 774 * Remove a write request from an inode 775 */ 776static void nfs_inode_remove_request(struct nfs_page *req) 777{ 778 struct nfs_inode *nfsi = NFS_I(nfs_page_to_inode(req)); 779 780 if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) { 781 struct folio *folio = nfs_page_to_folio(req->wb_head); 782 struct address_space *mapping = folio_file_mapping(folio); 783 784 spin_lock(&mapping->i_private_lock); 785 if (likely(folio && !folio_test_swapcache(folio))) { 786 folio->private = NULL; 787 folio_clear_private(folio); 788 clear_bit(PG_MAPPED, &req->wb_head->wb_flags); 789 } 790 spin_unlock(&mapping->i_private_lock); 791 } 792 793 if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags)) { 794 atomic_long_dec(&nfsi->nrequests); 795 nfs_release_request(req); 796 } 797} 798 799static void nfs_mark_request_dirty(struct nfs_page *req) 800{ 801 struct folio *folio = nfs_page_to_folio(req); 802 if (folio) 803 filemap_dirty_folio(folio_mapping(folio), folio); 804} 805 806/* 807 * nfs_page_search_commits_for_head_request_locked 808 * 809 * Search through commit lists on @inode for the head request for @folio. 810 * Must be called while holding the inode (which is cinfo) lock. 811 * 812 * Returns the head request if found, or NULL if not found. 813 */ 814static struct nfs_page * 815nfs_page_search_commits_for_head_request_locked(struct nfs_inode *nfsi, 816 struct folio *folio) 817{ 818 struct nfs_page *freq, *t; 819 struct nfs_commit_info cinfo; 820 struct inode *inode = &nfsi->vfs_inode; 821 822 nfs_init_cinfo_from_inode(&cinfo, inode); 823 824 /* search through pnfs commit lists */ 825 freq = pnfs_search_commit_reqs(inode, &cinfo, folio); 826 if (freq) 827 return freq->wb_head; 828 829 /* Linearly search the commit list for the correct request */ 830 list_for_each_entry_safe(freq, t, &cinfo.mds->list, wb_list) { 831 if (nfs_page_to_folio(freq) == folio) 832 return freq->wb_head; 833 } 834 835 return NULL; 836} 837 838/** 839 * nfs_request_add_commit_list_locked - add request to a commit list 840 * @req: pointer to a struct nfs_page 841 * @dst: commit list head 842 * @cinfo: holds list lock and accounting info 843 * 844 * This sets the PG_CLEAN bit, updates the cinfo count of 845 * number of outstanding requests requiring a commit as well as 846 * the MM page stats. 847 * 848 * The caller must hold NFS_I(cinfo->inode)->commit_mutex, and the 849 * nfs_page lock. 850 */ 851void 852nfs_request_add_commit_list_locked(struct nfs_page *req, struct list_head *dst, 853 struct nfs_commit_info *cinfo) 854{ 855 set_bit(PG_CLEAN, &req->wb_flags); 856 nfs_list_add_request(req, dst); 857 atomic_long_inc(&cinfo->mds->ncommit); 858} 859EXPORT_SYMBOL_GPL(nfs_request_add_commit_list_locked); 860 861/** 862 * nfs_request_add_commit_list - add request to a commit list 863 * @req: pointer to a struct nfs_page 864 * @cinfo: holds list lock and accounting info 865 * 866 * This sets the PG_CLEAN bit, updates the cinfo count of 867 * number of outstanding requests requiring a commit as well as 868 * the MM page stats. 869 * 870 * The caller must _not_ hold the cinfo->lock, but must be 871 * holding the nfs_page lock. 872 */ 873void 874nfs_request_add_commit_list(struct nfs_page *req, struct nfs_commit_info *cinfo) 875{ 876 mutex_lock(&NFS_I(cinfo->inode)->commit_mutex); 877 nfs_request_add_commit_list_locked(req, &cinfo->mds->list, cinfo); 878 mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex); 879 nfs_folio_mark_unstable(nfs_page_to_folio(req), cinfo); 880} 881EXPORT_SYMBOL_GPL(nfs_request_add_commit_list); 882 883/** 884 * nfs_request_remove_commit_list - Remove request from a commit list 885 * @req: pointer to a nfs_page 886 * @cinfo: holds list lock and accounting info 887 * 888 * This clears the PG_CLEAN bit, and updates the cinfo's count of 889 * number of outstanding requests requiring a commit 890 * It does not update the MM page stats. 891 * 892 * The caller _must_ hold the cinfo->lock and the nfs_page lock. 893 */ 894void 895nfs_request_remove_commit_list(struct nfs_page *req, 896 struct nfs_commit_info *cinfo) 897{ 898 if (!test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) 899 return; 900 nfs_list_remove_request(req); 901 atomic_long_dec(&cinfo->mds->ncommit); 902} 903EXPORT_SYMBOL_GPL(nfs_request_remove_commit_list); 904 905static void nfs_init_cinfo_from_inode(struct nfs_commit_info *cinfo, 906 struct inode *inode) 907{ 908 cinfo->inode = inode; 909 cinfo->mds = &NFS_I(inode)->commit_info; 910 cinfo->ds = pnfs_get_ds_info(inode); 911 cinfo->dreq = NULL; 912 cinfo->completion_ops = &nfs_commit_completion_ops; 913} 914 915void nfs_init_cinfo(struct nfs_commit_info *cinfo, 916 struct inode *inode, 917 struct nfs_direct_req *dreq) 918{ 919 if (dreq) 920 nfs_init_cinfo_from_dreq(cinfo, dreq); 921 else 922 nfs_init_cinfo_from_inode(cinfo, inode); 923} 924EXPORT_SYMBOL_GPL(nfs_init_cinfo); 925 926/* 927 * Add a request to the inode's commit list. 928 */ 929void 930nfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg, 931 struct nfs_commit_info *cinfo, u32 ds_commit_idx) 932{ 933 if (pnfs_mark_request_commit(req, lseg, cinfo, ds_commit_idx)) 934 return; 935 nfs_request_add_commit_list(req, cinfo); 936} 937 938static void nfs_folio_clear_commit(struct folio *folio) 939{ 940 if (folio) { 941 long nr = folio_nr_pages(folio); 942 943 node_stat_mod_folio(folio, NR_WRITEBACK, -nr); 944 wb_stat_mod(&inode_to_bdi(folio_file_mapping(folio)->host)->wb, 945 WB_WRITEBACK, -nr); 946 } 947} 948 949/* Called holding the request lock on @req */ 950static void nfs_clear_request_commit(struct nfs_commit_info *cinfo, 951 struct nfs_page *req) 952{ 953 if (test_bit(PG_CLEAN, &req->wb_flags)) { 954 struct nfs_open_context *ctx = nfs_req_openctx(req); 955 struct inode *inode = d_inode(ctx->dentry); 956 957 mutex_lock(&NFS_I(inode)->commit_mutex); 958 if (!pnfs_clear_request_commit(req, cinfo)) { 959 nfs_request_remove_commit_list(req, cinfo); 960 } 961 mutex_unlock(&NFS_I(inode)->commit_mutex); 962 nfs_folio_clear_commit(nfs_page_to_folio(req)); 963 } 964} 965 966int nfs_write_need_commit(struct nfs_pgio_header *hdr) 967{ 968 if (hdr->verf.committed == NFS_DATA_SYNC) 969 return hdr->lseg == NULL; 970 return hdr->verf.committed != NFS_FILE_SYNC; 971} 972 973static void nfs_async_write_init(struct nfs_pgio_header *hdr) 974{ 975 nfs_io_completion_get(hdr->io_completion); 976} 977 978static void nfs_write_completion(struct nfs_pgio_header *hdr) 979{ 980 struct nfs_commit_info cinfo; 981 unsigned long bytes = 0; 982 983 if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) 984 goto out; 985 nfs_init_cinfo_from_inode(&cinfo, hdr->inode); 986 while (!list_empty(&hdr->pages)) { 987 struct nfs_page *req = nfs_list_entry(hdr->pages.next); 988 989 bytes += req->wb_bytes; 990 nfs_list_remove_request(req); 991 if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) && 992 (hdr->good_bytes < bytes)) { 993 trace_nfs_comp_error(hdr->inode, req, hdr->error); 994 nfs_mapping_set_error(nfs_page_to_folio(req), 995 hdr->error); 996 goto remove_req; 997 } 998 if (nfs_write_need_commit(hdr)) { 999 /* Reset wb_nio, since the write was successful. */ 1000 req->wb_nio = 0; 1001 memcpy(&req->wb_verf, &hdr->verf.verifier, sizeof(req->wb_verf)); 1002 nfs_mark_request_commit(req, hdr->lseg, &cinfo, 1003 hdr->pgio_mirror_idx); 1004 goto next; 1005 } 1006remove_req: 1007 nfs_inode_remove_request(req); 1008next: 1009 nfs_page_end_writeback(req); 1010 nfs_release_request(req); 1011 } 1012out: 1013 nfs_io_completion_put(hdr->io_completion); 1014 hdr->release(hdr); 1015} 1016 1017unsigned long 1018nfs_reqs_to_commit(struct nfs_commit_info *cinfo) 1019{ 1020 return atomic_long_read(&cinfo->mds->ncommit); 1021} 1022 1023/* NFS_I(cinfo->inode)->commit_mutex held by caller */ 1024int 1025nfs_scan_commit_list(struct list_head *src, struct list_head *dst, 1026 struct nfs_commit_info *cinfo, int max) 1027{ 1028 struct nfs_page *req, *tmp; 1029 int ret = 0; 1030 1031 list_for_each_entry_safe(req, tmp, src, wb_list) { 1032 kref_get(&req->wb_kref); 1033 if (!nfs_lock_request(req)) { 1034 nfs_release_request(req); 1035 continue; 1036 } 1037 nfs_request_remove_commit_list(req, cinfo); 1038 clear_bit(PG_COMMIT_TO_DS, &req->wb_flags); 1039 nfs_list_add_request(req, dst); 1040 ret++; 1041 if ((ret == max) && !cinfo->dreq) 1042 break; 1043 cond_resched(); 1044 } 1045 return ret; 1046} 1047EXPORT_SYMBOL_GPL(nfs_scan_commit_list); 1048 1049/* 1050 * nfs_scan_commit - Scan an inode for commit requests 1051 * @inode: NFS inode to scan 1052 * @dst: mds destination list 1053 * @cinfo: mds and ds lists of reqs ready to commit 1054 * 1055 * Moves requests from the inode's 'commit' request list. 1056 * The requests are *not* checked to ensure that they form a contiguous set. 1057 */ 1058int 1059nfs_scan_commit(struct inode *inode, struct list_head *dst, 1060 struct nfs_commit_info *cinfo) 1061{ 1062 int ret = 0; 1063 1064 if (!atomic_long_read(&cinfo->mds->ncommit)) 1065 return 0; 1066 mutex_lock(&NFS_I(cinfo->inode)->commit_mutex); 1067 if (atomic_long_read(&cinfo->mds->ncommit) > 0) { 1068 const int max = INT_MAX; 1069 1070 ret = nfs_scan_commit_list(&cinfo->mds->list, dst, 1071 cinfo, max); 1072 ret += pnfs_scan_commit_lists(inode, cinfo, max - ret); 1073 } 1074 mutex_unlock(&NFS_I(cinfo->inode)->commit_mutex); 1075 return ret; 1076} 1077 1078/* 1079 * Search for an existing write request, and attempt to update 1080 * it to reflect a new dirty region on a given page. 1081 * 1082 * If the attempt fails, then the existing request is flushed out 1083 * to disk. 1084 */ 1085static struct nfs_page *nfs_try_to_update_request(struct folio *folio, 1086 unsigned int offset, 1087 unsigned int bytes) 1088{ 1089 struct nfs_page *req; 1090 unsigned int rqend; 1091 unsigned int end; 1092 int error; 1093 1094 end = offset + bytes; 1095 1096 req = nfs_lock_and_join_requests(folio); 1097 if (IS_ERR_OR_NULL(req)) 1098 return req; 1099 1100 rqend = req->wb_offset + req->wb_bytes; 1101 /* 1102 * Tell the caller to flush out the request if 1103 * the offsets are non-contiguous. 1104 * Note: nfs_flush_incompatible() will already 1105 * have flushed out requests having wrong owners. 1106 */ 1107 if (offset > rqend || end < req->wb_offset) 1108 goto out_flushme; 1109 1110 /* Okay, the request matches. Update the region */ 1111 if (offset < req->wb_offset) { 1112 req->wb_offset = offset; 1113 req->wb_pgbase = offset; 1114 } 1115 if (end > rqend) 1116 req->wb_bytes = end - req->wb_offset; 1117 else 1118 req->wb_bytes = rqend - req->wb_offset; 1119 req->wb_nio = 0; 1120 return req; 1121out_flushme: 1122 /* 1123 * Note: we mark the request dirty here because 1124 * nfs_lock_and_join_requests() cannot preserve 1125 * commit flags, so we have to replay the write. 1126 */ 1127 nfs_mark_request_dirty(req); 1128 nfs_unlock_and_release_request(req); 1129 error = nfs_wb_folio(folio_file_mapping(folio)->host, folio); 1130 return (error < 0) ? ERR_PTR(error) : NULL; 1131} 1132 1133/* 1134 * Try to update an existing write request, or create one if there is none. 1135 * 1136 * Note: Should always be called with the Page Lock held to prevent races 1137 * if we have to add a new request. Also assumes that the caller has 1138 * already called nfs_flush_incompatible() if necessary. 1139 */ 1140static struct nfs_page *nfs_setup_write_request(struct nfs_open_context *ctx, 1141 struct folio *folio, 1142 unsigned int offset, 1143 unsigned int bytes) 1144{ 1145 struct nfs_page *req; 1146 1147 req = nfs_try_to_update_request(folio, offset, bytes); 1148 if (req != NULL) 1149 goto out; 1150 req = nfs_page_create_from_folio(ctx, folio, offset, bytes); 1151 if (IS_ERR(req)) 1152 goto out; 1153 nfs_inode_add_request(req); 1154out: 1155 return req; 1156} 1157 1158static int nfs_writepage_setup(struct nfs_open_context *ctx, 1159 struct folio *folio, unsigned int offset, 1160 unsigned int count) 1161{ 1162 struct nfs_page *req; 1163 1164 req = nfs_setup_write_request(ctx, folio, offset, count); 1165 if (IS_ERR(req)) 1166 return PTR_ERR(req); 1167 /* Update file length */ 1168 nfs_grow_file(folio, offset, count); 1169 nfs_mark_uptodate(req); 1170 nfs_mark_request_dirty(req); 1171 nfs_unlock_and_release_request(req); 1172 return 0; 1173} 1174 1175int nfs_flush_incompatible(struct file *file, struct folio *folio) 1176{ 1177 struct nfs_open_context *ctx = nfs_file_open_context(file); 1178 struct nfs_lock_context *l_ctx; 1179 struct file_lock_context *flctx = locks_inode_context(file_inode(file)); 1180 struct nfs_page *req; 1181 int do_flush, status; 1182 /* 1183 * Look for a request corresponding to this page. If there 1184 * is one, and it belongs to another file, we flush it out 1185 * before we try to copy anything into the page. Do this 1186 * due to the lack of an ACCESS-type call in NFSv2. 1187 * Also do the same if we find a request from an existing 1188 * dropped page. 1189 */ 1190 do { 1191 req = nfs_folio_find_head_request(folio); 1192 if (req == NULL) 1193 return 0; 1194 l_ctx = req->wb_lock_context; 1195 do_flush = nfs_page_to_folio(req) != folio || 1196 !nfs_match_open_context(nfs_req_openctx(req), ctx); 1197 if (l_ctx && flctx && 1198 !(list_empty_careful(&flctx->flc_posix) && 1199 list_empty_careful(&flctx->flc_flock))) { 1200 do_flush |= l_ctx->lockowner != current->files; 1201 } 1202 nfs_release_request(req); 1203 if (!do_flush) 1204 return 0; 1205 status = nfs_wb_folio(folio_file_mapping(folio)->host, folio); 1206 } while (status == 0); 1207 return status; 1208} 1209 1210/* 1211 * Avoid buffered writes when a open context credential's key would 1212 * expire soon. 1213 * 1214 * Returns -EACCES if the key will expire within RPC_KEY_EXPIRE_FAIL. 1215 * 1216 * Return 0 and set a credential flag which triggers the inode to flush 1217 * and performs NFS_FILE_SYNC writes if the key will expired within 1218 * RPC_KEY_EXPIRE_TIMEO. 1219 */ 1220int 1221nfs_key_timeout_notify(struct file *filp, struct inode *inode) 1222{ 1223 struct nfs_open_context *ctx = nfs_file_open_context(filp); 1224 1225 if (nfs_ctx_key_to_expire(ctx, inode) && 1226 !rcu_access_pointer(ctx->ll_cred)) 1227 /* Already expired! */ 1228 return -EACCES; 1229 return 0; 1230} 1231 1232/* 1233 * Test if the open context credential key is marked to expire soon. 1234 */ 1235bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx, struct inode *inode) 1236{ 1237 struct rpc_auth *auth = NFS_SERVER(inode)->client->cl_auth; 1238 struct rpc_cred *cred, *new, *old = NULL; 1239 struct auth_cred acred = { 1240 .cred = ctx->cred, 1241 }; 1242 bool ret = false; 1243 1244 rcu_read_lock(); 1245 cred = rcu_dereference(ctx->ll_cred); 1246 if (cred && !(cred->cr_ops->crkey_timeout && 1247 cred->cr_ops->crkey_timeout(cred))) 1248 goto out; 1249 rcu_read_unlock(); 1250 1251 new = auth->au_ops->lookup_cred(auth, &acred, 0); 1252 if (new == cred) { 1253 put_rpccred(new); 1254 return true; 1255 } 1256 if (IS_ERR_OR_NULL(new)) { 1257 new = NULL; 1258 ret = true; 1259 } else if (new->cr_ops->crkey_timeout && 1260 new->cr_ops->crkey_timeout(new)) 1261 ret = true; 1262 1263 rcu_read_lock(); 1264 old = rcu_dereference_protected(xchg(&ctx->ll_cred, 1265 RCU_INITIALIZER(new)), 1); 1266out: 1267 rcu_read_unlock(); 1268 put_rpccred(old); 1269 return ret; 1270} 1271 1272/* 1273 * If the page cache is marked as unsafe or invalid, then we can't rely on 1274 * the PageUptodate() flag. In this case, we will need to turn off 1275 * write optimisations that depend on the page contents being correct. 1276 */ 1277static bool nfs_folio_write_uptodate(struct folio *folio, unsigned int pagelen) 1278{ 1279 struct inode *inode = folio_file_mapping(folio)->host; 1280 struct nfs_inode *nfsi = NFS_I(inode); 1281 1282 if (nfs_have_delegated_attributes(inode)) 1283 goto out; 1284 if (nfsi->cache_validity & 1285 (NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_SIZE)) 1286 return false; 1287 smp_rmb(); 1288 if (test_bit(NFS_INO_INVALIDATING, &nfsi->flags) && pagelen != 0) 1289 return false; 1290out: 1291 if (nfsi->cache_validity & NFS_INO_INVALID_DATA && pagelen != 0) 1292 return false; 1293 return folio_test_uptodate(folio) != 0; 1294} 1295 1296static bool 1297is_whole_file_wrlock(struct file_lock *fl) 1298{ 1299 return fl->fl_start == 0 && fl->fl_end == OFFSET_MAX && 1300 lock_is_write(fl); 1301} 1302 1303/* If we know the page is up to date, and we're not using byte range locks (or 1304 * if we have the whole file locked for writing), it may be more efficient to 1305 * extend the write to cover the entire page in order to avoid fragmentation 1306 * inefficiencies. 1307 * 1308 * If the file is opened for synchronous writes then we can just skip the rest 1309 * of the checks. 1310 */ 1311static int nfs_can_extend_write(struct file *file, struct folio *folio, 1312 unsigned int pagelen) 1313{ 1314 struct inode *inode = file_inode(file); 1315 struct file_lock_context *flctx = locks_inode_context(inode); 1316 struct file_lock *fl; 1317 int ret; 1318 1319 if (file->f_flags & O_DSYNC) 1320 return 0; 1321 if (!nfs_folio_write_uptodate(folio, pagelen)) 1322 return 0; 1323 if (NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) 1324 return 1; 1325 if (!flctx || (list_empty_careful(&flctx->flc_flock) && 1326 list_empty_careful(&flctx->flc_posix))) 1327 return 1; 1328 1329 /* Check to see if there are whole file write locks */ 1330 ret = 0; 1331 spin_lock(&flctx->flc_lock); 1332 if (!list_empty(&flctx->flc_posix)) { 1333 fl = list_first_entry(&flctx->flc_posix, struct file_lock, 1334 c.flc_list); 1335 if (is_whole_file_wrlock(fl)) 1336 ret = 1; 1337 } else if (!list_empty(&flctx->flc_flock)) { 1338 fl = list_first_entry(&flctx->flc_flock, struct file_lock, 1339 c.flc_list); 1340 if (lock_is_write(fl)) 1341 ret = 1; 1342 } 1343 spin_unlock(&flctx->flc_lock); 1344 return ret; 1345} 1346 1347/* 1348 * Update and possibly write a cached page of an NFS file. 1349 * 1350 * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad 1351 * things with a page scheduled for an RPC call (e.g. invalidate it). 1352 */ 1353int nfs_update_folio(struct file *file, struct folio *folio, 1354 unsigned int offset, unsigned int count) 1355{ 1356 struct nfs_open_context *ctx = nfs_file_open_context(file); 1357 struct address_space *mapping = folio_file_mapping(folio); 1358 struct inode *inode = mapping->host; 1359 unsigned int pagelen = nfs_folio_length(folio); 1360 int status = 0; 1361 1362 nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); 1363 1364 dprintk("NFS: nfs_update_folio(%pD2 %d@%lld)\n", file, count, 1365 (long long)(folio_file_pos(folio) + offset)); 1366 1367 if (!count) 1368 goto out; 1369 1370 if (nfs_can_extend_write(file, folio, pagelen)) { 1371 count = max(count + offset, pagelen); 1372 offset = 0; 1373 } 1374 1375 status = nfs_writepage_setup(ctx, folio, offset, count); 1376 if (status < 0) 1377 nfs_set_pageerror(mapping); 1378out: 1379 dprintk("NFS: nfs_update_folio returns %d (isize %lld)\n", 1380 status, (long long)i_size_read(inode)); 1381 return status; 1382} 1383 1384static int flush_task_priority(int how) 1385{ 1386 switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { 1387 case FLUSH_HIGHPRI: 1388 return RPC_PRIORITY_HIGH; 1389 case FLUSH_LOWPRI: 1390 return RPC_PRIORITY_LOW; 1391 } 1392 return RPC_PRIORITY_NORMAL; 1393} 1394 1395static void nfs_initiate_write(struct nfs_pgio_header *hdr, 1396 struct rpc_message *msg, 1397 const struct nfs_rpc_ops *rpc_ops, 1398 struct rpc_task_setup *task_setup_data, int how) 1399{ 1400 int priority = flush_task_priority(how); 1401 1402 if (IS_SWAPFILE(hdr->inode)) 1403 task_setup_data->flags |= RPC_TASK_SWAPPER; 1404 task_setup_data->priority = priority; 1405 rpc_ops->write_setup(hdr, msg, &task_setup_data->rpc_client); 1406 trace_nfs_initiate_write(hdr); 1407} 1408 1409/* If a nfs_flush_* function fails, it should remove reqs from @head and 1410 * call this on each, which will prepare them to be retried on next 1411 * writeback using standard nfs. 1412 */ 1413static void nfs_redirty_request(struct nfs_page *req) 1414{ 1415 struct nfs_inode *nfsi = NFS_I(nfs_page_to_inode(req)); 1416 1417 /* Bump the transmission count */ 1418 req->wb_nio++; 1419 nfs_mark_request_dirty(req); 1420 atomic_long_inc(&nfsi->redirtied_pages); 1421 nfs_page_end_writeback(req); 1422 nfs_release_request(req); 1423} 1424 1425static void nfs_async_write_error(struct list_head *head, int error) 1426{ 1427 struct nfs_page *req; 1428 1429 while (!list_empty(head)) { 1430 req = nfs_list_entry(head->next); 1431 nfs_list_remove_request(req); 1432 if (nfs_error_is_fatal_on_server(error)) 1433 nfs_write_error(req, error); 1434 else 1435 nfs_redirty_request(req); 1436 } 1437} 1438 1439static void nfs_async_write_reschedule_io(struct nfs_pgio_header *hdr) 1440{ 1441 nfs_async_write_error(&hdr->pages, 0); 1442} 1443 1444static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops = { 1445 .init_hdr = nfs_async_write_init, 1446 .error_cleanup = nfs_async_write_error, 1447 .completion = nfs_write_completion, 1448 .reschedule_io = nfs_async_write_reschedule_io, 1449}; 1450 1451void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, 1452 struct inode *inode, int ioflags, bool force_mds, 1453 const struct nfs_pgio_completion_ops *compl_ops) 1454{ 1455 struct nfs_server *server = NFS_SERVER(inode); 1456 const struct nfs_pageio_ops *pg_ops = &nfs_pgio_rw_ops; 1457 1458#ifdef CONFIG_NFS_V4_1 1459 if (server->pnfs_curr_ld && !force_mds) 1460 pg_ops = server->pnfs_curr_ld->pg_write_ops; 1461#endif 1462 nfs_pageio_init(pgio, inode, pg_ops, compl_ops, &nfs_rw_write_ops, 1463 server->wsize, ioflags); 1464} 1465EXPORT_SYMBOL_GPL(nfs_pageio_init_write); 1466 1467void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio) 1468{ 1469 struct nfs_pgio_mirror *mirror; 1470 1471 if (pgio->pg_ops && pgio->pg_ops->pg_cleanup) 1472 pgio->pg_ops->pg_cleanup(pgio); 1473 1474 pgio->pg_ops = &nfs_pgio_rw_ops; 1475 1476 nfs_pageio_stop_mirroring(pgio); 1477 1478 mirror = &pgio->pg_mirrors[0]; 1479 mirror->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize; 1480} 1481EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds); 1482 1483 1484void nfs_commit_prepare(struct rpc_task *task, void *calldata) 1485{ 1486 struct nfs_commit_data *data = calldata; 1487 1488 NFS_PROTO(data->inode)->commit_rpc_prepare(task, data); 1489} 1490 1491static void nfs_writeback_check_extend(struct nfs_pgio_header *hdr, 1492 struct nfs_fattr *fattr) 1493{ 1494 struct nfs_pgio_args *argp = &hdr->args; 1495 struct nfs_pgio_res *resp = &hdr->res; 1496 u64 size = argp->offset + resp->count; 1497 1498 if (!(fattr->valid & NFS_ATTR_FATTR_SIZE)) 1499 fattr->size = size; 1500 if (nfs_size_to_loff_t(fattr->size) < i_size_read(hdr->inode)) { 1501 fattr->valid &= ~NFS_ATTR_FATTR_SIZE; 1502 return; 1503 } 1504 if (size != fattr->size) 1505 return; 1506 /* Set attribute barrier */ 1507 nfs_fattr_set_barrier(fattr); 1508 /* ...and update size */ 1509 fattr->valid |= NFS_ATTR_FATTR_SIZE; 1510} 1511 1512void nfs_writeback_update_inode(struct nfs_pgio_header *hdr) 1513{ 1514 struct nfs_fattr *fattr = &hdr->fattr; 1515 struct inode *inode = hdr->inode; 1516 1517 spin_lock(&inode->i_lock); 1518 nfs_writeback_check_extend(hdr, fattr); 1519 nfs_post_op_update_inode_force_wcc_locked(inode, fattr); 1520 spin_unlock(&inode->i_lock); 1521} 1522EXPORT_SYMBOL_GPL(nfs_writeback_update_inode); 1523 1524/* 1525 * This function is called when the WRITE call is complete. 1526 */ 1527static int nfs_writeback_done(struct rpc_task *task, 1528 struct nfs_pgio_header *hdr, 1529 struct inode *inode) 1530{ 1531 int status; 1532 1533 /* 1534 * ->write_done will attempt to use post-op attributes to detect 1535 * conflicting writes by other clients. A strict interpretation 1536 * of close-to-open would allow us to continue caching even if 1537 * another writer had changed the file, but some applications 1538 * depend on tighter cache coherency when writing. 1539 */ 1540 status = NFS_PROTO(inode)->write_done(task, hdr); 1541 if (status != 0) 1542 return status; 1543 1544 nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, hdr->res.count); 1545 trace_nfs_writeback_done(task, hdr); 1546 1547 if (task->tk_status >= 0) { 1548 enum nfs3_stable_how committed = hdr->res.verf->committed; 1549 1550 if (committed == NFS_UNSTABLE) { 1551 /* 1552 * We have some uncommitted data on the server at 1553 * this point, so ensure that we keep track of that 1554 * fact irrespective of what later writes do. 1555 */ 1556 set_bit(NFS_IOHDR_UNSTABLE_WRITES, &hdr->flags); 1557 } 1558 1559 if (committed < hdr->args.stable) { 1560 /* We tried a write call, but the server did not 1561 * commit data to stable storage even though we 1562 * requested it. 1563 * Note: There is a known bug in Tru64 < 5.0 in which 1564 * the server reports NFS_DATA_SYNC, but performs 1565 * NFS_FILE_SYNC. We therefore implement this checking 1566 * as a dprintk() in order to avoid filling syslog. 1567 */ 1568 static unsigned long complain; 1569 1570 /* Note this will print the MDS for a DS write */ 1571 if (time_before(complain, jiffies)) { 1572 dprintk("NFS: faulty NFS server %s:" 1573 " (committed = %d) != (stable = %d)\n", 1574 NFS_SERVER(inode)->nfs_client->cl_hostname, 1575 committed, hdr->args.stable); 1576 complain = jiffies + 300 * HZ; 1577 } 1578 } 1579 } 1580 1581 /* Deal with the suid/sgid bit corner case */ 1582 if (nfs_should_remove_suid(inode)) { 1583 spin_lock(&inode->i_lock); 1584 nfs_set_cache_invalid(inode, NFS_INO_INVALID_MODE); 1585 spin_unlock(&inode->i_lock); 1586 } 1587 return 0; 1588} 1589 1590/* 1591 * This function is called when the WRITE call is complete. 1592 */ 1593static void nfs_writeback_result(struct rpc_task *task, 1594 struct nfs_pgio_header *hdr) 1595{ 1596 struct nfs_pgio_args *argp = &hdr->args; 1597 struct nfs_pgio_res *resp = &hdr->res; 1598 1599 if (resp->count < argp->count) { 1600 static unsigned long complain; 1601 1602 /* This a short write! */ 1603 nfs_inc_stats(hdr->inode, NFSIOS_SHORTWRITE); 1604 1605 /* Has the server at least made some progress? */ 1606 if (resp->count == 0) { 1607 if (time_before(complain, jiffies)) { 1608 printk(KERN_WARNING 1609 "NFS: Server wrote zero bytes, expected %u.\n", 1610 argp->count); 1611 complain = jiffies + 300 * HZ; 1612 } 1613 nfs_set_pgio_error(hdr, -EIO, argp->offset); 1614 task->tk_status = -EIO; 1615 return; 1616 } 1617 1618 /* For non rpc-based layout drivers, retry-through-MDS */ 1619 if (!task->tk_ops) { 1620 hdr->pnfs_error = -EAGAIN; 1621 return; 1622 } 1623 1624 /* Was this an NFSv2 write or an NFSv3 stable write? */ 1625 if (resp->verf->committed != NFS_UNSTABLE) { 1626 /* Resend from where the server left off */ 1627 hdr->mds_offset += resp->count; 1628 argp->offset += resp->count; 1629 argp->pgbase += resp->count; 1630 argp->count -= resp->count; 1631 } else { 1632 /* Resend as a stable write in order to avoid 1633 * headaches in the case of a server crash. 1634 */ 1635 argp->stable = NFS_FILE_SYNC; 1636 } 1637 resp->count = 0; 1638 resp->verf->committed = 0; 1639 rpc_restart_call_prepare(task); 1640 } 1641} 1642 1643static int wait_on_commit(struct nfs_mds_commit_info *cinfo) 1644{ 1645 return wait_var_event_killable(&cinfo->rpcs_out, 1646 !atomic_read(&cinfo->rpcs_out)); 1647} 1648 1649void nfs_commit_begin(struct nfs_mds_commit_info *cinfo) 1650{ 1651 atomic_inc(&cinfo->rpcs_out); 1652} 1653 1654bool nfs_commit_end(struct nfs_mds_commit_info *cinfo) 1655{ 1656 if (atomic_dec_and_test(&cinfo->rpcs_out)) { 1657 wake_up_var(&cinfo->rpcs_out); 1658 return true; 1659 } 1660 return false; 1661} 1662 1663void nfs_commitdata_release(struct nfs_commit_data *data) 1664{ 1665 put_nfs_open_context(data->context); 1666 nfs_commit_free(data); 1667} 1668EXPORT_SYMBOL_GPL(nfs_commitdata_release); 1669 1670int nfs_initiate_commit(struct rpc_clnt *clnt, struct nfs_commit_data *data, 1671 const struct nfs_rpc_ops *nfs_ops, 1672 const struct rpc_call_ops *call_ops, 1673 int how, int flags) 1674{ 1675 struct rpc_task *task; 1676 int priority = flush_task_priority(how); 1677 struct rpc_message msg = { 1678 .rpc_argp = &data->args, 1679 .rpc_resp = &data->res, 1680 .rpc_cred = data->cred, 1681 }; 1682 struct rpc_task_setup task_setup_data = { 1683 .task = &data->task, 1684 .rpc_client = clnt, 1685 .rpc_message = &msg, 1686 .callback_ops = call_ops, 1687 .callback_data = data, 1688 .workqueue = nfsiod_workqueue, 1689 .flags = RPC_TASK_ASYNC | flags, 1690 .priority = priority, 1691 }; 1692 1693 if (nfs_server_capable(data->inode, NFS_CAP_MOVEABLE)) 1694 task_setup_data.flags |= RPC_TASK_MOVEABLE; 1695 1696 /* Set up the initial task struct. */ 1697 nfs_ops->commit_setup(data, &msg, &task_setup_data.rpc_client); 1698 trace_nfs_initiate_commit(data); 1699 1700 dprintk("NFS: initiated commit call\n"); 1701 1702 task = rpc_run_task(&task_setup_data); 1703 if (IS_ERR(task)) 1704 return PTR_ERR(task); 1705 if (how & FLUSH_SYNC) 1706 rpc_wait_for_completion_task(task); 1707 rpc_put_task(task); 1708 return 0; 1709} 1710EXPORT_SYMBOL_GPL(nfs_initiate_commit); 1711 1712static loff_t nfs_get_lwb(struct list_head *head) 1713{ 1714 loff_t lwb = 0; 1715 struct nfs_page *req; 1716 1717 list_for_each_entry(req, head, wb_list) 1718 if (lwb < (req_offset(req) + req->wb_bytes)) 1719 lwb = req_offset(req) + req->wb_bytes; 1720 1721 return lwb; 1722} 1723 1724/* 1725 * Set up the argument/result storage required for the RPC call. 1726 */ 1727void nfs_init_commit(struct nfs_commit_data *data, 1728 struct list_head *head, 1729 struct pnfs_layout_segment *lseg, 1730 struct nfs_commit_info *cinfo) 1731{ 1732 struct nfs_page *first; 1733 struct nfs_open_context *ctx; 1734 struct inode *inode; 1735 1736 /* Set up the RPC argument and reply structs 1737 * NB: take care not to mess about with data->commit et al. */ 1738 1739 if (head) 1740 list_splice_init(head, &data->pages); 1741 1742 first = nfs_list_entry(data->pages.next); 1743 ctx = nfs_req_openctx(first); 1744 inode = d_inode(ctx->dentry); 1745 1746 data->inode = inode; 1747 data->cred = ctx->cred; 1748 data->lseg = lseg; /* reference transferred */ 1749 /* only set lwb for pnfs commit */ 1750 if (lseg) 1751 data->lwb = nfs_get_lwb(&data->pages); 1752 data->mds_ops = &nfs_commit_ops; 1753 data->completion_ops = cinfo->completion_ops; 1754 data->dreq = cinfo->dreq; 1755 1756 data->args.fh = NFS_FH(data->inode); 1757 /* Note: we always request a commit of the entire inode */ 1758 data->args.offset = 0; 1759 data->args.count = 0; 1760 data->context = get_nfs_open_context(ctx); 1761 data->res.fattr = &data->fattr; 1762 data->res.verf = &data->verf; 1763 nfs_fattr_init(&data->fattr); 1764 nfs_commit_begin(cinfo->mds); 1765} 1766EXPORT_SYMBOL_GPL(nfs_init_commit); 1767 1768void nfs_retry_commit(struct list_head *page_list, 1769 struct pnfs_layout_segment *lseg, 1770 struct nfs_commit_info *cinfo, 1771 u32 ds_commit_idx) 1772{ 1773 struct nfs_page *req; 1774 1775 while (!list_empty(page_list)) { 1776 req = nfs_list_entry(page_list->next); 1777 nfs_list_remove_request(req); 1778 nfs_mark_request_commit(req, lseg, cinfo, ds_commit_idx); 1779 nfs_folio_clear_commit(nfs_page_to_folio(req)); 1780 nfs_unlock_and_release_request(req); 1781 } 1782} 1783EXPORT_SYMBOL_GPL(nfs_retry_commit); 1784 1785static void nfs_commit_resched_write(struct nfs_commit_info *cinfo, 1786 struct nfs_page *req) 1787{ 1788 struct folio *folio = nfs_page_to_folio(req); 1789 1790 filemap_dirty_folio(folio_mapping(folio), folio); 1791} 1792 1793/* 1794 * Commit dirty pages 1795 */ 1796static int 1797nfs_commit_list(struct inode *inode, struct list_head *head, int how, 1798 struct nfs_commit_info *cinfo) 1799{ 1800 struct nfs_commit_data *data; 1801 unsigned short task_flags = 0; 1802 1803 /* another commit raced with us */ 1804 if (list_empty(head)) 1805 return 0; 1806 1807 data = nfs_commitdata_alloc(); 1808 if (!data) { 1809 nfs_retry_commit(head, NULL, cinfo, -1); 1810 return -ENOMEM; 1811 } 1812 1813 /* Set up the argument struct */ 1814 nfs_init_commit(data, head, NULL, cinfo); 1815 if (NFS_SERVER(inode)->nfs_client->cl_minorversion) 1816 task_flags = RPC_TASK_MOVEABLE; 1817 return nfs_initiate_commit(NFS_CLIENT(inode), data, NFS_PROTO(inode), 1818 data->mds_ops, how, 1819 RPC_TASK_CRED_NOREF | task_flags); 1820} 1821 1822/* 1823 * COMMIT call returned 1824 */ 1825static void nfs_commit_done(struct rpc_task *task, void *calldata) 1826{ 1827 struct nfs_commit_data *data = calldata; 1828 1829 /* Call the NFS version-specific code */ 1830 NFS_PROTO(data->inode)->commit_done(task, data); 1831 trace_nfs_commit_done(task, data); 1832} 1833 1834static void nfs_commit_release_pages(struct nfs_commit_data *data) 1835{ 1836 const struct nfs_writeverf *verf = data->res.verf; 1837 struct nfs_page *req; 1838 int status = data->task.tk_status; 1839 struct nfs_commit_info cinfo; 1840 struct nfs_server *nfss; 1841 struct folio *folio; 1842 1843 while (!list_empty(&data->pages)) { 1844 req = nfs_list_entry(data->pages.next); 1845 nfs_list_remove_request(req); 1846 folio = nfs_page_to_folio(req); 1847 nfs_folio_clear_commit(folio); 1848 1849 dprintk("NFS: commit (%s/%llu %d@%lld)", 1850 nfs_req_openctx(req)->dentry->d_sb->s_id, 1851 (unsigned long long)NFS_FILEID(d_inode(nfs_req_openctx(req)->dentry)), 1852 req->wb_bytes, 1853 (long long)req_offset(req)); 1854 if (status < 0) { 1855 if (folio) { 1856 trace_nfs_commit_error(data->inode, req, 1857 status); 1858 nfs_mapping_set_error(folio, status); 1859 nfs_inode_remove_request(req); 1860 } 1861 dprintk_cont(", error = %d\n", status); 1862 goto next; 1863 } 1864 1865 /* Okay, COMMIT succeeded, apparently. Check the verifier 1866 * returned by the server against all stored verfs. */ 1867 if (nfs_write_match_verf(verf, req)) { 1868 /* We have a match */ 1869 if (folio) 1870 nfs_inode_remove_request(req); 1871 dprintk_cont(" OK\n"); 1872 goto next; 1873 } 1874 /* We have a mismatch. Write the page again */ 1875 dprintk_cont(" mismatch\n"); 1876 nfs_mark_request_dirty(req); 1877 atomic_long_inc(&NFS_I(data->inode)->redirtied_pages); 1878 next: 1879 nfs_unlock_and_release_request(req); 1880 /* Latency breaker */ 1881 cond_resched(); 1882 } 1883 nfss = NFS_SERVER(data->inode); 1884 if (atomic_long_read(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) 1885 nfss->write_congested = 0; 1886 1887 nfs_init_cinfo(&cinfo, data->inode, data->dreq); 1888 nfs_commit_end(cinfo.mds); 1889} 1890 1891static void nfs_commit_release(void *calldata) 1892{ 1893 struct nfs_commit_data *data = calldata; 1894 1895 data->completion_ops->completion(data); 1896 nfs_commitdata_release(calldata); 1897} 1898 1899static const struct rpc_call_ops nfs_commit_ops = { 1900 .rpc_call_prepare = nfs_commit_prepare, 1901 .rpc_call_done = nfs_commit_done, 1902 .rpc_release = nfs_commit_release, 1903}; 1904 1905static const struct nfs_commit_completion_ops nfs_commit_completion_ops = { 1906 .completion = nfs_commit_release_pages, 1907 .resched_write = nfs_commit_resched_write, 1908}; 1909 1910int nfs_generic_commit_list(struct inode *inode, struct list_head *head, 1911 int how, struct nfs_commit_info *cinfo) 1912{ 1913 int status; 1914 1915 status = pnfs_commit_list(inode, head, how, cinfo); 1916 if (status == PNFS_NOT_ATTEMPTED) 1917 status = nfs_commit_list(inode, head, how, cinfo); 1918 return status; 1919} 1920 1921static int __nfs_commit_inode(struct inode *inode, int how, 1922 struct writeback_control *wbc) 1923{ 1924 LIST_HEAD(head); 1925 struct nfs_commit_info cinfo; 1926 int may_wait = how & FLUSH_SYNC; 1927 int ret, nscan; 1928 1929 how &= ~FLUSH_SYNC; 1930 nfs_init_cinfo_from_inode(&cinfo, inode); 1931 nfs_commit_begin(cinfo.mds); 1932 for (;;) { 1933 ret = nscan = nfs_scan_commit(inode, &head, &cinfo); 1934 if (ret <= 0) 1935 break; 1936 ret = nfs_generic_commit_list(inode, &head, how, &cinfo); 1937 if (ret < 0) 1938 break; 1939 ret = 0; 1940 if (wbc && wbc->sync_mode == WB_SYNC_NONE) { 1941 if (nscan < wbc->nr_to_write) 1942 wbc->nr_to_write -= nscan; 1943 else 1944 wbc->nr_to_write = 0; 1945 } 1946 if (nscan < INT_MAX) 1947 break; 1948 cond_resched(); 1949 } 1950 nfs_commit_end(cinfo.mds); 1951 if (ret || !may_wait) 1952 return ret; 1953 return wait_on_commit(cinfo.mds); 1954} 1955 1956int nfs_commit_inode(struct inode *inode, int how) 1957{ 1958 return __nfs_commit_inode(inode, how, NULL); 1959} 1960EXPORT_SYMBOL_GPL(nfs_commit_inode); 1961 1962int nfs_write_inode(struct inode *inode, struct writeback_control *wbc) 1963{ 1964 struct nfs_inode *nfsi = NFS_I(inode); 1965 int flags = FLUSH_SYNC; 1966 int ret = 0; 1967 1968 if (wbc->sync_mode == WB_SYNC_NONE) { 1969 /* no commits means nothing needs to be done */ 1970 if (!atomic_long_read(&nfsi->commit_info.ncommit)) 1971 goto check_requests_outstanding; 1972 1973 /* Don't commit yet if this is a non-blocking flush and there 1974 * are a lot of outstanding writes for this mapping. 1975 */ 1976 if (mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK)) 1977 goto out_mark_dirty; 1978 1979 /* don't wait for the COMMIT response */ 1980 flags = 0; 1981 } 1982 1983 ret = __nfs_commit_inode(inode, flags, wbc); 1984 if (!ret) { 1985 if (flags & FLUSH_SYNC) 1986 return 0; 1987 } else if (atomic_long_read(&nfsi->commit_info.ncommit)) 1988 goto out_mark_dirty; 1989 1990check_requests_outstanding: 1991 if (!atomic_read(&nfsi->commit_info.rpcs_out)) 1992 return ret; 1993out_mark_dirty: 1994 __mark_inode_dirty(inode, I_DIRTY_DATASYNC); 1995 return ret; 1996} 1997EXPORT_SYMBOL_GPL(nfs_write_inode); 1998 1999/* 2000 * Wrapper for filemap_write_and_wait_range() 2001 * 2002 * Needed for pNFS in order to ensure data becomes visible to the 2003 * client. 2004 */ 2005int nfs_filemap_write_and_wait_range(struct address_space *mapping, 2006 loff_t lstart, loff_t lend) 2007{ 2008 int ret; 2009 2010 ret = filemap_write_and_wait_range(mapping, lstart, lend); 2011 if (ret == 0) 2012 ret = pnfs_sync_inode(mapping->host, true); 2013 return ret; 2014} 2015EXPORT_SYMBOL_GPL(nfs_filemap_write_and_wait_range); 2016 2017/* 2018 * flush the inode to disk. 2019 */ 2020int nfs_wb_all(struct inode *inode) 2021{ 2022 int ret; 2023 2024 trace_nfs_writeback_inode_enter(inode); 2025 2026 ret = filemap_write_and_wait(inode->i_mapping); 2027 if (ret) 2028 goto out; 2029 ret = nfs_commit_inode(inode, FLUSH_SYNC); 2030 if (ret < 0) 2031 goto out; 2032 pnfs_sync_inode(inode, true); 2033 ret = 0; 2034 2035out: 2036 trace_nfs_writeback_inode_exit(inode, ret); 2037 return ret; 2038} 2039EXPORT_SYMBOL_GPL(nfs_wb_all); 2040 2041int nfs_wb_folio_cancel(struct inode *inode, struct folio *folio) 2042{ 2043 struct nfs_page *req; 2044 int ret = 0; 2045 2046 folio_wait_writeback(folio); 2047 2048 /* blocking call to cancel all requests and join to a single (head) 2049 * request */ 2050 req = nfs_lock_and_join_requests(folio); 2051 2052 if (IS_ERR(req)) { 2053 ret = PTR_ERR(req); 2054 } else if (req) { 2055 /* all requests from this folio have been cancelled by 2056 * nfs_lock_and_join_requests, so just remove the head 2057 * request from the inode / page_private pointer and 2058 * release it */ 2059 nfs_inode_remove_request(req); 2060 nfs_unlock_and_release_request(req); 2061 } 2062 2063 return ret; 2064} 2065 2066/** 2067 * nfs_wb_folio - Write back all requests on one page 2068 * @inode: pointer to page 2069 * @folio: pointer to folio 2070 * 2071 * Assumes that the folio has been locked by the caller, and will 2072 * not unlock it. 2073 */ 2074int nfs_wb_folio(struct inode *inode, struct folio *folio) 2075{ 2076 loff_t range_start = folio_file_pos(folio); 2077 loff_t range_end = range_start + (loff_t)folio_size(folio) - 1; 2078 struct writeback_control wbc = { 2079 .sync_mode = WB_SYNC_ALL, 2080 .nr_to_write = 0, 2081 .range_start = range_start, 2082 .range_end = range_end, 2083 }; 2084 int ret; 2085 2086 trace_nfs_writeback_folio(inode, folio); 2087 2088 for (;;) { 2089 folio_wait_writeback(folio); 2090 if (folio_clear_dirty_for_io(folio)) { 2091 ret = nfs_writepage_locked(folio, &wbc); 2092 if (ret < 0) 2093 goto out_error; 2094 continue; 2095 } 2096 ret = 0; 2097 if (!folio_test_private(folio)) 2098 break; 2099 ret = nfs_commit_inode(inode, FLUSH_SYNC); 2100 if (ret < 0) 2101 goto out_error; 2102 } 2103out_error: 2104 trace_nfs_writeback_folio_done(inode, folio, ret); 2105 return ret; 2106} 2107 2108#ifdef CONFIG_MIGRATION 2109int nfs_migrate_folio(struct address_space *mapping, struct folio *dst, 2110 struct folio *src, enum migrate_mode mode) 2111{ 2112 /* 2113 * If the private flag is set, the folio is currently associated with 2114 * an in-progress read or write request. Don't try to migrate it. 2115 * 2116 * FIXME: we could do this in principle, but we'll need a way to ensure 2117 * that we can safely release the inode reference while holding 2118 * the folio lock. 2119 */ 2120 if (folio_test_private(src)) 2121 return -EBUSY; 2122 2123 if (folio_test_fscache(src)) { 2124 if (mode == MIGRATE_ASYNC) 2125 return -EBUSY; 2126 folio_wait_fscache(src); 2127 } 2128 2129 return migrate_folio(mapping, dst, src, mode); 2130} 2131#endif 2132 2133int __init nfs_init_writepagecache(void) 2134{ 2135 nfs_wdata_cachep = kmem_cache_create("nfs_write_data", 2136 sizeof(struct nfs_pgio_header), 2137 0, SLAB_HWCACHE_ALIGN, 2138 NULL); 2139 if (nfs_wdata_cachep == NULL) 2140 return -ENOMEM; 2141 2142 nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE, 2143 nfs_wdata_cachep); 2144 if (nfs_wdata_mempool == NULL) 2145 goto out_destroy_write_cache; 2146 2147 nfs_cdata_cachep = kmem_cache_create("nfs_commit_data", 2148 sizeof(struct nfs_commit_data), 2149 0, SLAB_HWCACHE_ALIGN, 2150 NULL); 2151 if (nfs_cdata_cachep == NULL) 2152 goto out_destroy_write_mempool; 2153 2154 nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, 2155 nfs_cdata_cachep); 2156 if (nfs_commit_mempool == NULL) 2157 goto out_destroy_commit_cache; 2158 2159 /* 2160 * NFS congestion size, scale with available memory. 2161 * 2162 * 64MB: 8192k 2163 * 128MB: 11585k 2164 * 256MB: 16384k 2165 * 512MB: 23170k 2166 * 1GB: 32768k 2167 * 2GB: 46340k 2168 * 4GB: 65536k 2169 * 8GB: 92681k 2170 * 16GB: 131072k 2171 * 2172 * This allows larger machines to have larger/more transfers. 2173 * Limit the default to 256M 2174 */ 2175 nfs_congestion_kb = (16*int_sqrt(totalram_pages())) << (PAGE_SHIFT-10); 2176 if (nfs_congestion_kb > 256*1024) 2177 nfs_congestion_kb = 256*1024; 2178 2179 return 0; 2180 2181out_destroy_commit_cache: 2182 kmem_cache_destroy(nfs_cdata_cachep); 2183out_destroy_write_mempool: 2184 mempool_destroy(nfs_wdata_mempool); 2185out_destroy_write_cache: 2186 kmem_cache_destroy(nfs_wdata_cachep); 2187 return -ENOMEM; 2188} 2189 2190void nfs_destroy_writepagecache(void) 2191{ 2192 mempool_destroy(nfs_commit_mempool); 2193 kmem_cache_destroy(nfs_cdata_cachep); 2194 mempool_destroy(nfs_wdata_mempool); 2195 kmem_cache_destroy(nfs_wdata_cachep); 2196} 2197 2198static const struct nfs_rw_ops nfs_rw_write_ops = { 2199 .rw_alloc_header = nfs_writehdr_alloc, 2200 .rw_free_header = nfs_writehdr_free, 2201 .rw_done = nfs_writeback_done, 2202 .rw_result = nfs_writeback_result, 2203 .rw_initiate = nfs_initiate_write, 2204}; 2205