Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.1.
   1/*
   2 * fs/f2fs/data.c
   3 *
   4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   5 *             http://www.samsung.com/
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 */
  11#include <linux/fs.h>
  12#include <linux/f2fs_fs.h>
  13#include <linux/buffer_head.h>
  14#include <linux/mpage.h>
  15#include <linux/writeback.h>
  16#include <linux/backing-dev.h>
  17#include <linux/pagevec.h>
  18#include <linux/blkdev.h>
  19#include <linux/bio.h>
  20#include <linux/prefetch.h>
  21#include <linux/uio.h>
  22#include <linux/cleancache.h>
  23
  24#include "f2fs.h"
  25#include "node.h"
  26#include "segment.h"
  27#include "trace.h"
  28#include <trace/events/f2fs.h>
  29
  30static void f2fs_read_end_io(struct bio *bio)
  31{
  32	struct bio_vec *bvec;
  33	int i;
  34
  35	if (f2fs_bio_encrypted(bio)) {
  36		if (bio->bi_error) {
  37			fscrypt_release_ctx(bio->bi_private);
  38		} else {
  39			fscrypt_decrypt_bio_pages(bio->bi_private, bio);
  40			return;
  41		}
  42	}
  43
  44	bio_for_each_segment_all(bvec, bio, i) {
  45		struct page *page = bvec->bv_page;
  46
  47		if (!bio->bi_error) {
  48			SetPageUptodate(page);
  49		} else {
  50			ClearPageUptodate(page);
  51			SetPageError(page);
  52		}
  53		unlock_page(page);
  54	}
  55	bio_put(bio);
  56}
  57
  58static void f2fs_write_end_io(struct bio *bio)
  59{
  60	struct f2fs_sb_info *sbi = bio->bi_private;
  61	struct bio_vec *bvec;
  62	int i;
  63
  64	bio_for_each_segment_all(bvec, bio, i) {
  65		struct page *page = bvec->bv_page;
  66
  67		fscrypt_pullback_bio_page(&page, true);
  68
  69		if (unlikely(bio->bi_error)) {
  70			set_bit(AS_EIO, &page->mapping->flags);
  71			f2fs_stop_checkpoint(sbi);
  72		}
  73		end_page_writeback(page);
  74		dec_page_count(sbi, F2FS_WRITEBACK);
  75	}
  76
  77	if (!get_pages(sbi, F2FS_WRITEBACK) && wq_has_sleeper(&sbi->cp_wait))
  78		wake_up(&sbi->cp_wait);
  79
  80	bio_put(bio);
  81}
  82
  83/*
  84 * Low-level block read/write IO operations.
  85 */
  86static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
  87				int npages, bool is_read)
  88{
  89	struct bio *bio;
  90
  91	bio = f2fs_bio_alloc(npages);
  92
  93	bio->bi_bdev = sbi->sb->s_bdev;
  94	bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr);
  95	bio->bi_end_io = is_read ? f2fs_read_end_io : f2fs_write_end_io;
  96	bio->bi_private = is_read ? NULL : sbi;
  97
  98	return bio;
  99}
 100
 101static void __submit_merged_bio(struct f2fs_bio_info *io)
 102{
 103	struct f2fs_io_info *fio = &io->fio;
 104
 105	if (!io->bio)
 106		return;
 107
 108	if (is_read_io(fio->rw))
 109		trace_f2fs_submit_read_bio(io->sbi->sb, fio, io->bio);
 110	else
 111		trace_f2fs_submit_write_bio(io->sbi->sb, fio, io->bio);
 112
 113	submit_bio(fio->rw, io->bio);
 114	io->bio = NULL;
 115}
 116
 117static bool __has_merged_page(struct f2fs_bio_info *io, struct inode *inode,
 118						struct page *page, nid_t ino)
 119{
 120	struct bio_vec *bvec;
 121	struct page *target;
 122	int i;
 123
 124	if (!io->bio)
 125		return false;
 126
 127	if (!inode && !page && !ino)
 128		return true;
 129
 130	bio_for_each_segment_all(bvec, io->bio, i) {
 131
 132		if (bvec->bv_page->mapping)
 133			target = bvec->bv_page;
 134		else
 135			target = fscrypt_control_page(bvec->bv_page);
 136
 137		if (inode && inode == target->mapping->host)
 138			return true;
 139		if (page && page == target)
 140			return true;
 141		if (ino && ino == ino_of_node(target))
 142			return true;
 143	}
 144
 145	return false;
 146}
 147
 148static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
 149						struct page *page, nid_t ino,
 150						enum page_type type)
 151{
 152	enum page_type btype = PAGE_TYPE_OF_BIO(type);
 153	struct f2fs_bio_info *io = &sbi->write_io[btype];
 154	bool ret;
 155
 156	down_read(&io->io_rwsem);
 157	ret = __has_merged_page(io, inode, page, ino);
 158	up_read(&io->io_rwsem);
 159	return ret;
 160}
 161
 162static void __f2fs_submit_merged_bio(struct f2fs_sb_info *sbi,
 163				struct inode *inode, struct page *page,
 164				nid_t ino, enum page_type type, int rw)
 165{
 166	enum page_type btype = PAGE_TYPE_OF_BIO(type);
 167	struct f2fs_bio_info *io;
 168
 169	io = is_read_io(rw) ? &sbi->read_io : &sbi->write_io[btype];
 170
 171	down_write(&io->io_rwsem);
 172
 173	if (!__has_merged_page(io, inode, page, ino))
 174		goto out;
 175
 176	/* change META to META_FLUSH in the checkpoint procedure */
 177	if (type >= META_FLUSH) {
 178		io->fio.type = META_FLUSH;
 179		if (test_opt(sbi, NOBARRIER))
 180			io->fio.rw = WRITE_FLUSH | REQ_META | REQ_PRIO;
 181		else
 182			io->fio.rw = WRITE_FLUSH_FUA | REQ_META | REQ_PRIO;
 183	}
 184	__submit_merged_bio(io);
 185out:
 186	up_write(&io->io_rwsem);
 187}
 188
 189void f2fs_submit_merged_bio(struct f2fs_sb_info *sbi, enum page_type type,
 190									int rw)
 191{
 192	__f2fs_submit_merged_bio(sbi, NULL, NULL, 0, type, rw);
 193}
 194
 195void f2fs_submit_merged_bio_cond(struct f2fs_sb_info *sbi,
 196				struct inode *inode, struct page *page,
 197				nid_t ino, enum page_type type, int rw)
 198{
 199	if (has_merged_page(sbi, inode, page, ino, type))
 200		__f2fs_submit_merged_bio(sbi, inode, page, ino, type, rw);
 201}
 202
 203void f2fs_flush_merged_bios(struct f2fs_sb_info *sbi)
 204{
 205	f2fs_submit_merged_bio(sbi, DATA, WRITE);
 206	f2fs_submit_merged_bio(sbi, NODE, WRITE);
 207	f2fs_submit_merged_bio(sbi, META, WRITE);
 208}
 209
 210/*
 211 * Fill the locked page with data located in the block address.
 212 * Return unlocked page.
 213 */
 214int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 215{
 216	struct bio *bio;
 217	struct page *page = fio->encrypted_page ?
 218			fio->encrypted_page : fio->page;
 219
 220	trace_f2fs_submit_page_bio(page, fio);
 221	f2fs_trace_ios(fio, 0);
 222
 223	/* Allocate a new bio */
 224	bio = __bio_alloc(fio->sbi, fio->new_blkaddr, 1, is_read_io(fio->rw));
 225
 226	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
 227		bio_put(bio);
 228		return -EFAULT;
 229	}
 230
 231	submit_bio(fio->rw, bio);
 232	return 0;
 233}
 234
 235void f2fs_submit_page_mbio(struct f2fs_io_info *fio)
 236{
 237	struct f2fs_sb_info *sbi = fio->sbi;
 238	enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
 239	struct f2fs_bio_info *io;
 240	bool is_read = is_read_io(fio->rw);
 241	struct page *bio_page;
 242
 243	io = is_read ? &sbi->read_io : &sbi->write_io[btype];
 244
 245	if (fio->old_blkaddr != NEW_ADDR)
 246		verify_block_addr(sbi, fio->old_blkaddr);
 247	verify_block_addr(sbi, fio->new_blkaddr);
 248
 249	down_write(&io->io_rwsem);
 250
 251	if (!is_read)
 252		inc_page_count(sbi, F2FS_WRITEBACK);
 253
 254	if (io->bio && (io->last_block_in_bio != fio->new_blkaddr - 1 ||
 255						io->fio.rw != fio->rw))
 256		__submit_merged_bio(io);
 257alloc_new:
 258	if (io->bio == NULL) {
 259		int bio_blocks = MAX_BIO_BLOCKS(sbi);
 260
 261		io->bio = __bio_alloc(sbi, fio->new_blkaddr,
 262						bio_blocks, is_read);
 263		io->fio = *fio;
 264	}
 265
 266	bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
 267
 268	if (bio_add_page(io->bio, bio_page, PAGE_SIZE, 0) <
 269							PAGE_SIZE) {
 270		__submit_merged_bio(io);
 271		goto alloc_new;
 272	}
 273
 274	io->last_block_in_bio = fio->new_blkaddr;
 275	f2fs_trace_ios(fio, 0);
 276
 277	up_write(&io->io_rwsem);
 278	trace_f2fs_submit_page_mbio(fio->page, fio);
 279}
 280
 281/*
 282 * Lock ordering for the change of data block address:
 283 * ->data_page
 284 *  ->node_page
 285 *    update block addresses in the node page
 286 */
 287void set_data_blkaddr(struct dnode_of_data *dn)
 288{
 289	struct f2fs_node *rn;
 290	__le32 *addr_array;
 291	struct page *node_page = dn->node_page;
 292	unsigned int ofs_in_node = dn->ofs_in_node;
 293
 294	f2fs_wait_on_page_writeback(node_page, NODE, true);
 295
 296	rn = F2FS_NODE(node_page);
 297
 298	/* Get physical address of data block */
 299	addr_array = blkaddr_in_node(rn);
 300	addr_array[ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
 301	if (set_page_dirty(node_page))
 302		dn->node_changed = true;
 303}
 304
 305void f2fs_update_data_blkaddr(struct dnode_of_data *dn, block_t blkaddr)
 306{
 307	dn->data_blkaddr = blkaddr;
 308	set_data_blkaddr(dn);
 309	f2fs_update_extent_cache(dn);
 310}
 311
 312int reserve_new_block(struct dnode_of_data *dn)
 313{
 314	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 315
 316	if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
 317		return -EPERM;
 318	if (unlikely(!inc_valid_block_count(sbi, dn->inode, 1)))
 319		return -ENOSPC;
 320
 321	trace_f2fs_reserve_new_block(dn->inode, dn->nid, dn->ofs_in_node);
 322
 323	dn->data_blkaddr = NEW_ADDR;
 324	set_data_blkaddr(dn);
 325	mark_inode_dirty(dn->inode);
 326	sync_inode_page(dn);
 327	return 0;
 328}
 329
 330int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
 331{
 332	bool need_put = dn->inode_page ? false : true;
 333	int err;
 334
 335	err = get_dnode_of_data(dn, index, ALLOC_NODE);
 336	if (err)
 337		return err;
 338
 339	if (dn->data_blkaddr == NULL_ADDR)
 340		err = reserve_new_block(dn);
 341	if (err || need_put)
 342		f2fs_put_dnode(dn);
 343	return err;
 344}
 345
 346int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index)
 347{
 348	struct extent_info ei;
 349	struct inode *inode = dn->inode;
 350
 351	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 352		dn->data_blkaddr = ei.blk + index - ei.fofs;
 353		return 0;
 354	}
 355
 356	return f2fs_reserve_block(dn, index);
 357}
 358
 359struct page *get_read_data_page(struct inode *inode, pgoff_t index,
 360						int rw, bool for_write)
 361{
 362	struct address_space *mapping = inode->i_mapping;
 363	struct dnode_of_data dn;
 364	struct page *page;
 365	struct extent_info ei;
 366	int err;
 367	struct f2fs_io_info fio = {
 368		.sbi = F2FS_I_SB(inode),
 369		.type = DATA,
 370		.rw = rw,
 371		.encrypted_page = NULL,
 372	};
 373
 374	if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
 375		return read_mapping_page(mapping, index, NULL);
 376
 377	page = f2fs_grab_cache_page(mapping, index, for_write);
 378	if (!page)
 379		return ERR_PTR(-ENOMEM);
 380
 381	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 382		dn.data_blkaddr = ei.blk + index - ei.fofs;
 383		goto got_it;
 384	}
 385
 386	set_new_dnode(&dn, inode, NULL, NULL, 0);
 387	err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
 388	if (err)
 389		goto put_err;
 390	f2fs_put_dnode(&dn);
 391
 392	if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
 393		err = -ENOENT;
 394		goto put_err;
 395	}
 396got_it:
 397	if (PageUptodate(page)) {
 398		unlock_page(page);
 399		return page;
 400	}
 401
 402	/*
 403	 * A new dentry page is allocated but not able to be written, since its
 404	 * new inode page couldn't be allocated due to -ENOSPC.
 405	 * In such the case, its blkaddr can be remained as NEW_ADDR.
 406	 * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
 407	 */
 408	if (dn.data_blkaddr == NEW_ADDR) {
 409		zero_user_segment(page, 0, PAGE_SIZE);
 410		SetPageUptodate(page);
 411		unlock_page(page);
 412		return page;
 413	}
 414
 415	fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr;
 416	fio.page = page;
 417	err = f2fs_submit_page_bio(&fio);
 418	if (err)
 419		goto put_err;
 420	return page;
 421
 422put_err:
 423	f2fs_put_page(page, 1);
 424	return ERR_PTR(err);
 425}
 426
 427struct page *find_data_page(struct inode *inode, pgoff_t index)
 428{
 429	struct address_space *mapping = inode->i_mapping;
 430	struct page *page;
 431
 432	page = find_get_page(mapping, index);
 433	if (page && PageUptodate(page))
 434		return page;
 435	f2fs_put_page(page, 0);
 436
 437	page = get_read_data_page(inode, index, READ_SYNC, false);
 438	if (IS_ERR(page))
 439		return page;
 440
 441	if (PageUptodate(page))
 442		return page;
 443
 444	wait_on_page_locked(page);
 445	if (unlikely(!PageUptodate(page))) {
 446		f2fs_put_page(page, 0);
 447		return ERR_PTR(-EIO);
 448	}
 449	return page;
 450}
 451
 452/*
 453 * If it tries to access a hole, return an error.
 454 * Because, the callers, functions in dir.c and GC, should be able to know
 455 * whether this page exists or not.
 456 */
 457struct page *get_lock_data_page(struct inode *inode, pgoff_t index,
 458							bool for_write)
 459{
 460	struct address_space *mapping = inode->i_mapping;
 461	struct page *page;
 462repeat:
 463	page = get_read_data_page(inode, index, READ_SYNC, for_write);
 464	if (IS_ERR(page))
 465		return page;
 466
 467	/* wait for read completion */
 468	lock_page(page);
 469	if (unlikely(!PageUptodate(page))) {
 470		f2fs_put_page(page, 1);
 471		return ERR_PTR(-EIO);
 472	}
 473	if (unlikely(page->mapping != mapping)) {
 474		f2fs_put_page(page, 1);
 475		goto repeat;
 476	}
 477	return page;
 478}
 479
 480/*
 481 * Caller ensures that this data page is never allocated.
 482 * A new zero-filled data page is allocated in the page cache.
 483 *
 484 * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
 485 * f2fs_unlock_op().
 486 * Note that, ipage is set only by make_empty_dir, and if any error occur,
 487 * ipage should be released by this function.
 488 */
 489struct page *get_new_data_page(struct inode *inode,
 490		struct page *ipage, pgoff_t index, bool new_i_size)
 491{
 492	struct address_space *mapping = inode->i_mapping;
 493	struct page *page;
 494	struct dnode_of_data dn;
 495	int err;
 496
 497	page = f2fs_grab_cache_page(mapping, index, true);
 498	if (!page) {
 499		/*
 500		 * before exiting, we should make sure ipage will be released
 501		 * if any error occur.
 502		 */
 503		f2fs_put_page(ipage, 1);
 504		return ERR_PTR(-ENOMEM);
 505	}
 506
 507	set_new_dnode(&dn, inode, ipage, NULL, 0);
 508	err = f2fs_reserve_block(&dn, index);
 509	if (err) {
 510		f2fs_put_page(page, 1);
 511		return ERR_PTR(err);
 512	}
 513	if (!ipage)
 514		f2fs_put_dnode(&dn);
 515
 516	if (PageUptodate(page))
 517		goto got_it;
 518
 519	if (dn.data_blkaddr == NEW_ADDR) {
 520		zero_user_segment(page, 0, PAGE_SIZE);
 521		SetPageUptodate(page);
 522	} else {
 523		f2fs_put_page(page, 1);
 524
 525		/* if ipage exists, blkaddr should be NEW_ADDR */
 526		f2fs_bug_on(F2FS_I_SB(inode), ipage);
 527		page = get_lock_data_page(inode, index, true);
 528		if (IS_ERR(page))
 529			return page;
 530	}
 531got_it:
 532	if (new_i_size && i_size_read(inode) <
 533				((loff_t)(index + 1) << PAGE_SHIFT)) {
 534		i_size_write(inode, ((loff_t)(index + 1) << PAGE_SHIFT));
 535		/* Only the directory inode sets new_i_size */
 536		set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR);
 537	}
 538	return page;
 539}
 540
 541static int __allocate_data_block(struct dnode_of_data *dn)
 542{
 543	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 544	struct f2fs_summary sum;
 545	struct node_info ni;
 546	int seg = CURSEG_WARM_DATA;
 547	pgoff_t fofs;
 548
 549	if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
 550		return -EPERM;
 551
 552	dn->data_blkaddr = datablock_addr(dn->node_page, dn->ofs_in_node);
 553	if (dn->data_blkaddr == NEW_ADDR)
 554		goto alloc;
 555
 556	if (unlikely(!inc_valid_block_count(sbi, dn->inode, 1)))
 557		return -ENOSPC;
 558
 559alloc:
 560	get_node_info(sbi, dn->nid, &ni);
 561	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
 562
 563	if (dn->ofs_in_node == 0 && dn->inode_page == dn->node_page)
 564		seg = CURSEG_DIRECT_IO;
 565
 566	allocate_data_block(sbi, NULL, dn->data_blkaddr, &dn->data_blkaddr,
 567								&sum, seg);
 568	set_data_blkaddr(dn);
 569
 570	/* update i_size */
 571	fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
 572							dn->ofs_in_node;
 573	if (i_size_read(dn->inode) < ((loff_t)(fofs + 1) << PAGE_SHIFT))
 574		i_size_write(dn->inode,
 575				((loff_t)(fofs + 1) << PAGE_SHIFT));
 576	return 0;
 577}
 578
 579ssize_t f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
 580{
 581	struct inode *inode = file_inode(iocb->ki_filp);
 582	struct f2fs_map_blocks map;
 583	ssize_t ret = 0;
 584
 585	map.m_lblk = F2FS_BYTES_TO_BLK(iocb->ki_pos);
 586	map.m_len = F2FS_BLK_ALIGN(iov_iter_count(from));
 587	map.m_next_pgofs = NULL;
 588
 589	if (f2fs_encrypted_inode(inode))
 590		return 0;
 591
 592	if (iocb->ki_flags & IOCB_DIRECT) {
 593		ret = f2fs_convert_inline_inode(inode);
 594		if (ret)
 595			return ret;
 596		return f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_PRE_DIO);
 597	}
 598	if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA) {
 599		ret = f2fs_convert_inline_inode(inode);
 600		if (ret)
 601			return ret;
 602	}
 603	if (!f2fs_has_inline_data(inode))
 604		return f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_PRE_AIO);
 605	return ret;
 606}
 607
 608/*
 609 * f2fs_map_blocks() now supported readahead/bmap/rw direct_IO with
 610 * f2fs_map_blocks structure.
 611 * If original data blocks are allocated, then give them to blockdev.
 612 * Otherwise,
 613 *     a. preallocate requested block addresses
 614 *     b. do not use extent cache for better performance
 615 *     c. give the block addresses to blockdev
 616 */
 617int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
 618						int create, int flag)
 619{
 620	unsigned int maxblocks = map->m_len;
 621	struct dnode_of_data dn;
 622	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 623	int mode = create ? ALLOC_NODE : LOOKUP_NODE_RA;
 624	pgoff_t pgofs, end_offset;
 625	int err = 0, ofs = 1;
 626	struct extent_info ei;
 627	bool allocated = false;
 628	block_t blkaddr;
 629
 630	map->m_len = 0;
 631	map->m_flags = 0;
 632
 633	/* it only supports block size == page size */
 634	pgofs =	(pgoff_t)map->m_lblk;
 635
 636	if (!create && f2fs_lookup_extent_cache(inode, pgofs, &ei)) {
 637		map->m_pblk = ei.blk + pgofs - ei.fofs;
 638		map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs);
 639		map->m_flags = F2FS_MAP_MAPPED;
 640		goto out;
 641	}
 642
 643next_dnode:
 644	if (create)
 645		f2fs_lock_op(sbi);
 646
 647	/* When reading holes, we need its node page */
 648	set_new_dnode(&dn, inode, NULL, NULL, 0);
 649	err = get_dnode_of_data(&dn, pgofs, mode);
 650	if (err) {
 651		if (err == -ENOENT) {
 652			err = 0;
 653			if (map->m_next_pgofs)
 654				*map->m_next_pgofs =
 655					get_next_page_offset(&dn, pgofs);
 656		}
 657		goto unlock_out;
 658	}
 659
 660	end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
 661
 662next_block:
 663	blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);
 664
 665	if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR) {
 666		if (create) {
 667			if (unlikely(f2fs_cp_error(sbi))) {
 668				err = -EIO;
 669				goto sync_out;
 670			}
 671			if (flag == F2FS_GET_BLOCK_PRE_AIO) {
 672				if (blkaddr == NULL_ADDR)
 673					err = reserve_new_block(&dn);
 674			} else {
 675				err = __allocate_data_block(&dn);
 676			}
 677			if (err)
 678				goto sync_out;
 679			allocated = true;
 680			map->m_flags = F2FS_MAP_NEW;
 681			blkaddr = dn.data_blkaddr;
 682		} else {
 683			if (flag == F2FS_GET_BLOCK_FIEMAP &&
 684						blkaddr == NULL_ADDR) {
 685				if (map->m_next_pgofs)
 686					*map->m_next_pgofs = pgofs + 1;
 687			}
 688			if (flag != F2FS_GET_BLOCK_FIEMAP ||
 689						blkaddr != NEW_ADDR) {
 690				if (flag == F2FS_GET_BLOCK_BMAP)
 691					err = -ENOENT;
 692				goto sync_out;
 693			}
 694		}
 695	}
 696
 697	if (map->m_len == 0) {
 698		/* preallocated unwritten block should be mapped for fiemap. */
 699		if (blkaddr == NEW_ADDR)
 700			map->m_flags |= F2FS_MAP_UNWRITTEN;
 701		map->m_flags |= F2FS_MAP_MAPPED;
 702
 703		map->m_pblk = blkaddr;
 704		map->m_len = 1;
 705	} else if ((map->m_pblk != NEW_ADDR &&
 706			blkaddr == (map->m_pblk + ofs)) ||
 707			(map->m_pblk == NEW_ADDR && blkaddr == NEW_ADDR) ||
 708			flag == F2FS_GET_BLOCK_PRE_DIO ||
 709			flag == F2FS_GET_BLOCK_PRE_AIO) {
 710		ofs++;
 711		map->m_len++;
 712	} else {
 713		goto sync_out;
 714	}
 715
 716	dn.ofs_in_node++;
 717	pgofs++;
 718
 719	if (map->m_len < maxblocks) {
 720		if (dn.ofs_in_node < end_offset)
 721			goto next_block;
 722
 723		if (allocated)
 724			sync_inode_page(&dn);
 725		f2fs_put_dnode(&dn);
 726
 727		if (create) {
 728			f2fs_unlock_op(sbi);
 729			f2fs_balance_fs(sbi, allocated);
 730		}
 731		allocated = false;
 732		goto next_dnode;
 733	}
 734
 735sync_out:
 736	if (allocated)
 737		sync_inode_page(&dn);
 738	f2fs_put_dnode(&dn);
 739unlock_out:
 740	if (create) {
 741		f2fs_unlock_op(sbi);
 742		f2fs_balance_fs(sbi, allocated);
 743	}
 744out:
 745	trace_f2fs_map_blocks(inode, map, err);
 746	return err;
 747}
 748
 749static int __get_data_block(struct inode *inode, sector_t iblock,
 750			struct buffer_head *bh, int create, int flag,
 751			pgoff_t *next_pgofs)
 752{
 753	struct f2fs_map_blocks map;
 754	int ret;
 755
 756	map.m_lblk = iblock;
 757	map.m_len = bh->b_size >> inode->i_blkbits;
 758	map.m_next_pgofs = next_pgofs;
 759
 760	ret = f2fs_map_blocks(inode, &map, create, flag);
 761	if (!ret) {
 762		map_bh(bh, inode->i_sb, map.m_pblk);
 763		bh->b_state = (bh->b_state & ~F2FS_MAP_FLAGS) | map.m_flags;
 764		bh->b_size = map.m_len << inode->i_blkbits;
 765	}
 766	return ret;
 767}
 768
 769static int get_data_block(struct inode *inode, sector_t iblock,
 770			struct buffer_head *bh_result, int create, int flag,
 771			pgoff_t *next_pgofs)
 772{
 773	return __get_data_block(inode, iblock, bh_result, create,
 774							flag, next_pgofs);
 775}
 776
 777static int get_data_block_dio(struct inode *inode, sector_t iblock,
 778			struct buffer_head *bh_result, int create)
 779{
 780	return __get_data_block(inode, iblock, bh_result, create,
 781						F2FS_GET_BLOCK_DIO, NULL);
 782}
 783
 784static int get_data_block_bmap(struct inode *inode, sector_t iblock,
 785			struct buffer_head *bh_result, int create)
 786{
 787	/* Block number less than F2FS MAX BLOCKS */
 788	if (unlikely(iblock >= F2FS_I_SB(inode)->max_file_blocks))
 789		return -EFBIG;
 790
 791	return __get_data_block(inode, iblock, bh_result, create,
 792						F2FS_GET_BLOCK_BMAP, NULL);
 793}
 794
 795static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
 796{
 797	return (offset >> inode->i_blkbits);
 798}
 799
 800static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
 801{
 802	return (blk << inode->i_blkbits);
 803}
 804
 805int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 806		u64 start, u64 len)
 807{
 808	struct buffer_head map_bh;
 809	sector_t start_blk, last_blk;
 810	pgoff_t next_pgofs;
 811	loff_t isize;
 812	u64 logical = 0, phys = 0, size = 0;
 813	u32 flags = 0;
 814	int ret = 0;
 815
 816	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
 817	if (ret)
 818		return ret;
 819
 820	if (f2fs_has_inline_data(inode)) {
 821		ret = f2fs_inline_data_fiemap(inode, fieinfo, start, len);
 822		if (ret != -EAGAIN)
 823			return ret;
 824	}
 825
 826	inode_lock(inode);
 827
 828	isize = i_size_read(inode);
 829	if (start >= isize)
 830		goto out;
 831
 832	if (start + len > isize)
 833		len = isize - start;
 834
 835	if (logical_to_blk(inode, len) == 0)
 836		len = blk_to_logical(inode, 1);
 837
 838	start_blk = logical_to_blk(inode, start);
 839	last_blk = logical_to_blk(inode, start + len - 1);
 840
 841next:
 842	memset(&map_bh, 0, sizeof(struct buffer_head));
 843	map_bh.b_size = len;
 844
 845	ret = get_data_block(inode, start_blk, &map_bh, 0,
 846					F2FS_GET_BLOCK_FIEMAP, &next_pgofs);
 847	if (ret)
 848		goto out;
 849
 850	/* HOLE */
 851	if (!buffer_mapped(&map_bh)) {
 852		start_blk = next_pgofs;
 853		/* Go through holes util pass the EOF */
 854		if (blk_to_logical(inode, start_blk) < isize)
 855			goto prep_next;
 856		/* Found a hole beyond isize means no more extents.
 857		 * Note that the premise is that filesystems don't
 858		 * punch holes beyond isize and keep size unchanged.
 859		 */
 860		flags |= FIEMAP_EXTENT_LAST;
 861	}
 862
 863	if (size) {
 864		if (f2fs_encrypted_inode(inode))
 865			flags |= FIEMAP_EXTENT_DATA_ENCRYPTED;
 866
 867		ret = fiemap_fill_next_extent(fieinfo, logical,
 868				phys, size, flags);
 869	}
 870
 871	if (start_blk > last_blk || ret)
 872		goto out;
 873
 874	logical = blk_to_logical(inode, start_blk);
 875	phys = blk_to_logical(inode, map_bh.b_blocknr);
 876	size = map_bh.b_size;
 877	flags = 0;
 878	if (buffer_unwritten(&map_bh))
 879		flags = FIEMAP_EXTENT_UNWRITTEN;
 880
 881	start_blk += logical_to_blk(inode, size);
 882
 883prep_next:
 884	cond_resched();
 885	if (fatal_signal_pending(current))
 886		ret = -EINTR;
 887	else
 888		goto next;
 889out:
 890	if (ret == 1)
 891		ret = 0;
 892
 893	inode_unlock(inode);
 894	return ret;
 895}
 896
 897/*
 898 * This function was originally taken from fs/mpage.c, and customized for f2fs.
 899 * Major change was from block_size == page_size in f2fs by default.
 900 */
 901static int f2fs_mpage_readpages(struct address_space *mapping,
 902			struct list_head *pages, struct page *page,
 903			unsigned nr_pages)
 904{
 905	struct bio *bio = NULL;
 906	unsigned page_idx;
 907	sector_t last_block_in_bio = 0;
 908	struct inode *inode = mapping->host;
 909	const unsigned blkbits = inode->i_blkbits;
 910	const unsigned blocksize = 1 << blkbits;
 911	sector_t block_in_file;
 912	sector_t last_block;
 913	sector_t last_block_in_file;
 914	sector_t block_nr;
 915	struct block_device *bdev = inode->i_sb->s_bdev;
 916	struct f2fs_map_blocks map;
 917
 918	map.m_pblk = 0;
 919	map.m_lblk = 0;
 920	map.m_len = 0;
 921	map.m_flags = 0;
 922	map.m_next_pgofs = NULL;
 923
 924	for (page_idx = 0; nr_pages; page_idx++, nr_pages--) {
 925
 926		prefetchw(&page->flags);
 927		if (pages) {
 928			page = list_entry(pages->prev, struct page, lru);
 929			list_del(&page->lru);
 930			if (add_to_page_cache_lru(page, mapping,
 931						  page->index, GFP_KERNEL))
 932				goto next_page;
 933		}
 934
 935		block_in_file = (sector_t)page->index;
 936		last_block = block_in_file + nr_pages;
 937		last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
 938								blkbits;
 939		if (last_block > last_block_in_file)
 940			last_block = last_block_in_file;
 941
 942		/*
 943		 * Map blocks using the previous result first.
 944		 */
 945		if ((map.m_flags & F2FS_MAP_MAPPED) &&
 946				block_in_file > map.m_lblk &&
 947				block_in_file < (map.m_lblk + map.m_len))
 948			goto got_it;
 949
 950		/*
 951		 * Then do more f2fs_map_blocks() calls until we are
 952		 * done with this page.
 953		 */
 954		map.m_flags = 0;
 955
 956		if (block_in_file < last_block) {
 957			map.m_lblk = block_in_file;
 958			map.m_len = last_block - block_in_file;
 959
 960			if (f2fs_map_blocks(inode, &map, 0,
 961						F2FS_GET_BLOCK_READ))
 962				goto set_error_page;
 963		}
 964got_it:
 965		if ((map.m_flags & F2FS_MAP_MAPPED)) {
 966			block_nr = map.m_pblk + block_in_file - map.m_lblk;
 967			SetPageMappedToDisk(page);
 968
 969			if (!PageUptodate(page) && !cleancache_get_page(page)) {
 970				SetPageUptodate(page);
 971				goto confused;
 972			}
 973		} else {
 974			zero_user_segment(page, 0, PAGE_SIZE);
 975			SetPageUptodate(page);
 976			unlock_page(page);
 977			goto next_page;
 978		}
 979
 980		/*
 981		 * This page will go to BIO.  Do we need to send this
 982		 * BIO off first?
 983		 */
 984		if (bio && (last_block_in_bio != block_nr - 1)) {
 985submit_and_realloc:
 986			submit_bio(READ, bio);
 987			bio = NULL;
 988		}
 989		if (bio == NULL) {
 990			struct fscrypt_ctx *ctx = NULL;
 991
 992			if (f2fs_encrypted_inode(inode) &&
 993					S_ISREG(inode->i_mode)) {
 994
 995				ctx = fscrypt_get_ctx(inode, GFP_NOFS);
 996				if (IS_ERR(ctx))
 997					goto set_error_page;
 998
 999				/* wait the page to be moved by cleaning */
1000				f2fs_wait_on_encrypted_page_writeback(
1001						F2FS_I_SB(inode), block_nr);
1002			}
1003
1004			bio = bio_alloc(GFP_KERNEL,
1005				min_t(int, nr_pages, BIO_MAX_PAGES));
1006			if (!bio) {
1007				if (ctx)
1008					fscrypt_release_ctx(ctx);
1009				goto set_error_page;
1010			}
1011			bio->bi_bdev = bdev;
1012			bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(block_nr);
1013			bio->bi_end_io = f2fs_read_end_io;
1014			bio->bi_private = ctx;
1015		}
1016
1017		if (bio_add_page(bio, page, blocksize, 0) < blocksize)
1018			goto submit_and_realloc;
1019
1020		last_block_in_bio = block_nr;
1021		goto next_page;
1022set_error_page:
1023		SetPageError(page);
1024		zero_user_segment(page, 0, PAGE_SIZE);
1025		unlock_page(page);
1026		goto next_page;
1027confused:
1028		if (bio) {
1029			submit_bio(READ, bio);
1030			bio = NULL;
1031		}
1032		unlock_page(page);
1033next_page:
1034		if (pages)
1035			put_page(page);
1036	}
1037	BUG_ON(pages && !list_empty(pages));
1038	if (bio)
1039		submit_bio(READ, bio);
1040	return 0;
1041}
1042
1043static int f2fs_read_data_page(struct file *file, struct page *page)
1044{
1045	struct inode *inode = page->mapping->host;
1046	int ret = -EAGAIN;
1047
1048	trace_f2fs_readpage(page, DATA);
1049
1050	/* If the file has inline data, try to read it directly */
1051	if (f2fs_has_inline_data(inode))
1052		ret = f2fs_read_inline_data(inode, page);
1053	if (ret == -EAGAIN)
1054		ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1);
1055	return ret;
1056}
1057
1058static int f2fs_read_data_pages(struct file *file,
1059			struct address_space *mapping,
1060			struct list_head *pages, unsigned nr_pages)
1061{
1062	struct inode *inode = file->f_mapping->host;
1063	struct page *page = list_entry(pages->prev, struct page, lru);
1064
1065	trace_f2fs_readpages(inode, page, nr_pages);
1066
1067	/* If the file has inline data, skip readpages */
1068	if (f2fs_has_inline_data(inode))
1069		return 0;
1070
1071	return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages);
1072}
1073
1074int do_write_data_page(struct f2fs_io_info *fio)
1075{
1076	struct page *page = fio->page;
1077	struct inode *inode = page->mapping->host;
1078	struct dnode_of_data dn;
1079	int err = 0;
1080
1081	set_new_dnode(&dn, inode, NULL, NULL, 0);
1082	err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
1083	if (err)
1084		return err;
1085
1086	fio->old_blkaddr = dn.data_blkaddr;
1087
1088	/* This page is already truncated */
1089	if (fio->old_blkaddr == NULL_ADDR) {
1090		ClearPageUptodate(page);
1091		goto out_writepage;
1092	}
1093
1094	if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
1095		gfp_t gfp_flags = GFP_NOFS;
1096
1097		/* wait for GCed encrypted page writeback */
1098		f2fs_wait_on_encrypted_page_writeback(F2FS_I_SB(inode),
1099							fio->old_blkaddr);
1100retry_encrypt:
1101		fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page,
1102								gfp_flags);
1103		if (IS_ERR(fio->encrypted_page)) {
1104			err = PTR_ERR(fio->encrypted_page);
1105			if (err == -ENOMEM) {
1106				/* flush pending ios and wait for a while */
1107				f2fs_flush_merged_bios(F2FS_I_SB(inode));
1108				congestion_wait(BLK_RW_ASYNC, HZ/50);
1109				gfp_flags |= __GFP_NOFAIL;
1110				err = 0;
1111				goto retry_encrypt;
1112			}
1113			goto out_writepage;
1114		}
1115	}
1116
1117	set_page_writeback(page);
1118
1119	/*
1120	 * If current allocation needs SSR,
1121	 * it had better in-place writes for updated data.
1122	 */
1123	if (unlikely(fio->old_blkaddr != NEW_ADDR &&
1124			!is_cold_data(page) &&
1125			!IS_ATOMIC_WRITTEN_PAGE(page) &&
1126			need_inplace_update(inode))) {
1127		rewrite_data_page(fio);
1128		set_inode_flag(F2FS_I(inode), FI_UPDATE_WRITE);
1129		trace_f2fs_do_write_data_page(page, IPU);
1130	} else {
1131		write_data_page(&dn, fio);
1132		trace_f2fs_do_write_data_page(page, OPU);
1133		set_inode_flag(F2FS_I(inode), FI_APPEND_WRITE);
1134		if (page->index == 0)
1135			set_inode_flag(F2FS_I(inode), FI_FIRST_BLOCK_WRITTEN);
1136	}
1137out_writepage:
1138	f2fs_put_dnode(&dn);
1139	return err;
1140}
1141
1142static int f2fs_write_data_page(struct page *page,
1143					struct writeback_control *wbc)
1144{
1145	struct inode *inode = page->mapping->host;
1146	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1147	loff_t i_size = i_size_read(inode);
1148	const pgoff_t end_index = ((unsigned long long) i_size)
1149							>> PAGE_SHIFT;
1150	unsigned offset = 0;
1151	bool need_balance_fs = false;
1152	int err = 0;
1153	struct f2fs_io_info fio = {
1154		.sbi = sbi,
1155		.type = DATA,
1156		.rw = (wbc->sync_mode == WB_SYNC_ALL) ? WRITE_SYNC : WRITE,
1157		.page = page,
1158		.encrypted_page = NULL,
1159	};
1160
1161	trace_f2fs_writepage(page, DATA);
1162
1163	if (page->index < end_index)
1164		goto write;
1165
1166	/*
1167	 * If the offset is out-of-range of file size,
1168	 * this page does not have to be written to disk.
1169	 */
1170	offset = i_size & (PAGE_SIZE - 1);
1171	if ((page->index >= end_index + 1) || !offset)
1172		goto out;
1173
1174	zero_user_segment(page, offset, PAGE_SIZE);
1175write:
1176	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1177		goto redirty_out;
1178	if (f2fs_is_drop_cache(inode))
1179		goto out;
1180	if (f2fs_is_volatile_file(inode) && !wbc->for_reclaim &&
1181			available_free_memory(sbi, BASE_CHECK))
1182		goto redirty_out;
1183
1184	/* Dentry blocks are controlled by checkpoint */
1185	if (S_ISDIR(inode->i_mode)) {
1186		if (unlikely(f2fs_cp_error(sbi)))
1187			goto redirty_out;
1188		err = do_write_data_page(&fio);
1189		goto done;
1190	}
1191
1192	/* we should bypass data pages to proceed the kworkder jobs */
1193	if (unlikely(f2fs_cp_error(sbi))) {
1194		SetPageError(page);
1195		goto out;
1196	}
1197
1198	if (!wbc->for_reclaim)
1199		need_balance_fs = true;
1200	else if (has_not_enough_free_secs(sbi, 0))
1201		goto redirty_out;
1202
1203	err = -EAGAIN;
1204	f2fs_lock_op(sbi);
1205	if (f2fs_has_inline_data(inode))
1206		err = f2fs_write_inline_data(inode, page);
1207	if (err == -EAGAIN)
1208		err = do_write_data_page(&fio);
1209	f2fs_unlock_op(sbi);
1210done:
1211	if (err && err != -ENOENT)
1212		goto redirty_out;
1213
1214	clear_cold_data(page);
1215out:
1216	inode_dec_dirty_pages(inode);
1217	if (err)
1218		ClearPageUptodate(page);
1219
1220	if (wbc->for_reclaim) {
1221		f2fs_submit_merged_bio_cond(sbi, NULL, page, 0, DATA, WRITE);
1222		remove_dirty_inode(inode);
1223	}
1224
1225	unlock_page(page);
1226	f2fs_balance_fs(sbi, need_balance_fs);
1227
1228	if (unlikely(f2fs_cp_error(sbi)))
1229		f2fs_submit_merged_bio(sbi, DATA, WRITE);
1230
1231	return 0;
1232
1233redirty_out:
1234	redirty_page_for_writepage(wbc, page);
1235	return AOP_WRITEPAGE_ACTIVATE;
1236}
1237
1238static int __f2fs_writepage(struct page *page, struct writeback_control *wbc,
1239			void *data)
1240{
1241	struct address_space *mapping = data;
1242	int ret = mapping->a_ops->writepage(page, wbc);
1243	mapping_set_error(mapping, ret);
1244	return ret;
1245}
1246
1247/*
1248 * This function was copied from write_cche_pages from mm/page-writeback.c.
1249 * The major change is making write step of cold data page separately from
1250 * warm/hot data page.
1251 */
1252static int f2fs_write_cache_pages(struct address_space *mapping,
1253			struct writeback_control *wbc, writepage_t writepage,
1254			void *data)
1255{
1256	int ret = 0;
1257	int done = 0;
1258	struct pagevec pvec;
1259	int nr_pages;
1260	pgoff_t uninitialized_var(writeback_index);
1261	pgoff_t index;
1262	pgoff_t end;		/* Inclusive */
1263	pgoff_t done_index;
1264	int cycled;
1265	int range_whole = 0;
1266	int tag;
1267	int step = 0;
1268
1269	pagevec_init(&pvec, 0);
1270next:
1271	if (wbc->range_cyclic) {
1272		writeback_index = mapping->writeback_index; /* prev offset */
1273		index = writeback_index;
1274		if (index == 0)
1275			cycled = 1;
1276		else
1277			cycled = 0;
1278		end = -1;
1279	} else {
1280		index = wbc->range_start >> PAGE_SHIFT;
1281		end = wbc->range_end >> PAGE_SHIFT;
1282		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1283			range_whole = 1;
1284		cycled = 1; /* ignore range_cyclic tests */
1285	}
1286	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1287		tag = PAGECACHE_TAG_TOWRITE;
1288	else
1289		tag = PAGECACHE_TAG_DIRTY;
1290retry:
1291	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1292		tag_pages_for_writeback(mapping, index, end);
1293	done_index = index;
1294	while (!done && (index <= end)) {
1295		int i;
1296
1297		nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
1298			      min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1);
1299		if (nr_pages == 0)
1300			break;
1301
1302		for (i = 0; i < nr_pages; i++) {
1303			struct page *page = pvec.pages[i];
1304
1305			if (page->index > end) {
1306				done = 1;
1307				break;
1308			}
1309
1310			done_index = page->index;
1311
1312			lock_page(page);
1313
1314			if (unlikely(page->mapping != mapping)) {
1315continue_unlock:
1316				unlock_page(page);
1317				continue;
1318			}
1319
1320			if (!PageDirty(page)) {
1321				/* someone wrote it for us */
1322				goto continue_unlock;
1323			}
1324
1325			if (step == is_cold_data(page))
1326				goto continue_unlock;
1327
1328			if (PageWriteback(page)) {
1329				if (wbc->sync_mode != WB_SYNC_NONE)
1330					f2fs_wait_on_page_writeback(page,
1331								DATA, true);
1332				else
1333					goto continue_unlock;
1334			}
1335
1336			BUG_ON(PageWriteback(page));
1337			if (!clear_page_dirty_for_io(page))
1338				goto continue_unlock;
1339
1340			ret = (*writepage)(page, wbc, data);
1341			if (unlikely(ret)) {
1342				if (ret == AOP_WRITEPAGE_ACTIVATE) {
1343					unlock_page(page);
1344					ret = 0;
1345				} else {
1346					done_index = page->index + 1;
1347					done = 1;
1348					break;
1349				}
1350			}
1351
1352			if (--wbc->nr_to_write <= 0 &&
1353			    wbc->sync_mode == WB_SYNC_NONE) {
1354				done = 1;
1355				break;
1356			}
1357		}
1358		pagevec_release(&pvec);
1359		cond_resched();
1360	}
1361
1362	if (step < 1) {
1363		step++;
1364		goto next;
1365	}
1366
1367	if (!cycled && !done) {
1368		cycled = 1;
1369		index = 0;
1370		end = writeback_index - 1;
1371		goto retry;
1372	}
1373	if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1374		mapping->writeback_index = done_index;
1375
1376	return ret;
1377}
1378
1379static int f2fs_write_data_pages(struct address_space *mapping,
1380			    struct writeback_control *wbc)
1381{
1382	struct inode *inode = mapping->host;
1383	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1384	bool locked = false;
1385	int ret;
1386	long diff;
1387
1388	/* deal with chardevs and other special file */
1389	if (!mapping->a_ops->writepage)
1390		return 0;
1391
1392	/* skip writing if there is no dirty page in this inode */
1393	if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
1394		return 0;
1395
1396	if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
1397			get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
1398			available_free_memory(sbi, DIRTY_DENTS))
1399		goto skip_write;
1400
1401	/* skip writing during file defragment */
1402	if (is_inode_flag_set(F2FS_I(inode), FI_DO_DEFRAG))
1403		goto skip_write;
1404
1405	/* during POR, we don't need to trigger writepage at all. */
1406	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1407		goto skip_write;
1408
1409	trace_f2fs_writepages(mapping->host, wbc, DATA);
1410
1411	diff = nr_pages_to_write(sbi, DATA, wbc);
1412
1413	if (!S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_ALL) {
1414		mutex_lock(&sbi->writepages);
1415		locked = true;
1416	}
1417	ret = f2fs_write_cache_pages(mapping, wbc, __f2fs_writepage, mapping);
1418	f2fs_submit_merged_bio_cond(sbi, inode, NULL, 0, DATA, WRITE);
1419	if (locked)
1420		mutex_unlock(&sbi->writepages);
1421
1422	remove_dirty_inode(inode);
1423
1424	wbc->nr_to_write = max((long)0, wbc->nr_to_write - diff);
1425	return ret;
1426
1427skip_write:
1428	wbc->pages_skipped += get_dirty_pages(inode);
1429	trace_f2fs_writepages(mapping->host, wbc, DATA);
1430	return 0;
1431}
1432
1433static void f2fs_write_failed(struct address_space *mapping, loff_t to)
1434{
1435	struct inode *inode = mapping->host;
1436	loff_t i_size = i_size_read(inode);
1437
1438	if (to > i_size) {
1439		truncate_pagecache(inode, i_size);
1440		truncate_blocks(inode, i_size, true);
1441	}
1442}
1443
1444static int prepare_write_begin(struct f2fs_sb_info *sbi,
1445			struct page *page, loff_t pos, unsigned len,
1446			block_t *blk_addr, bool *node_changed)
1447{
1448	struct inode *inode = page->mapping->host;
1449	pgoff_t index = page->index;
1450	struct dnode_of_data dn;
1451	struct page *ipage;
1452	bool locked = false;
1453	struct extent_info ei;
1454	int err = 0;
1455
1456	/*
1457	 * we already allocated all the blocks, so we don't need to get
1458	 * the block addresses when there is no need to fill the page.
1459	 */
1460	if (!f2fs_has_inline_data(inode) && !f2fs_encrypted_inode(inode) &&
1461					len == PAGE_SIZE)
1462		return 0;
1463
1464	if (f2fs_has_inline_data(inode) ||
1465			(pos & PAGE_MASK) >= i_size_read(inode)) {
1466		f2fs_lock_op(sbi);
1467		locked = true;
1468	}
1469restart:
1470	/* check inline_data */
1471	ipage = get_node_page(sbi, inode->i_ino);
1472	if (IS_ERR(ipage)) {
1473		err = PTR_ERR(ipage);
1474		goto unlock_out;
1475	}
1476
1477	set_new_dnode(&dn, inode, ipage, ipage, 0);
1478
1479	if (f2fs_has_inline_data(inode)) {
1480		if (pos + len <= MAX_INLINE_DATA) {
1481			read_inline_data(page, ipage);
1482			set_inode_flag(F2FS_I(inode), FI_DATA_EXIST);
1483			set_inline_node(ipage);
1484		} else {
1485			err = f2fs_convert_inline_page(&dn, page);
1486			if (err)
1487				goto out;
1488			if (dn.data_blkaddr == NULL_ADDR)
1489				err = f2fs_get_block(&dn, index);
1490		}
1491	} else if (locked) {
1492		err = f2fs_get_block(&dn, index);
1493	} else {
1494		if (f2fs_lookup_extent_cache(inode, index, &ei)) {
1495			dn.data_blkaddr = ei.blk + index - ei.fofs;
1496		} else {
1497			/* hole case */
1498			err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
1499			if (err || (!err && dn.data_blkaddr == NULL_ADDR)) {
1500				f2fs_put_dnode(&dn);
1501				f2fs_lock_op(sbi);
1502				locked = true;
1503				goto restart;
1504			}
1505		}
1506	}
1507
1508	/* convert_inline_page can make node_changed */
1509	*blk_addr = dn.data_blkaddr;
1510	*node_changed = dn.node_changed;
1511out:
1512	f2fs_put_dnode(&dn);
1513unlock_out:
1514	if (locked)
1515		f2fs_unlock_op(sbi);
1516	return err;
1517}
1518
1519static int f2fs_write_begin(struct file *file, struct address_space *mapping,
1520		loff_t pos, unsigned len, unsigned flags,
1521		struct page **pagep, void **fsdata)
1522{
1523	struct inode *inode = mapping->host;
1524	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1525	struct page *page = NULL;
1526	pgoff_t index = ((unsigned long long) pos) >> PAGE_SHIFT;
1527	bool need_balance = false;
1528	block_t blkaddr = NULL_ADDR;
1529	int err = 0;
1530
1531	trace_f2fs_write_begin(inode, pos, len, flags);
1532
1533	/*
1534	 * We should check this at this moment to avoid deadlock on inode page
1535	 * and #0 page. The locking rule for inline_data conversion should be:
1536	 * lock_page(page #0) -> lock_page(inode_page)
1537	 */
1538	if (index != 0) {
1539		err = f2fs_convert_inline_inode(inode);
1540		if (err)
1541			goto fail;
1542	}
1543repeat:
1544	page = grab_cache_page_write_begin(mapping, index, flags);
1545	if (!page) {
1546		err = -ENOMEM;
1547		goto fail;
1548	}
1549
1550	*pagep = page;
1551
1552	err = prepare_write_begin(sbi, page, pos, len,
1553					&blkaddr, &need_balance);
1554	if (err)
1555		goto fail;
1556
1557	if (need_balance && has_not_enough_free_secs(sbi, 0)) {
1558		unlock_page(page);
1559		f2fs_balance_fs(sbi, true);
1560		lock_page(page);
1561		if (page->mapping != mapping) {
1562			/* The page got truncated from under us */
1563			f2fs_put_page(page, 1);
1564			goto repeat;
1565		}
1566	}
1567
1568	f2fs_wait_on_page_writeback(page, DATA, false);
1569
1570	/* wait for GCed encrypted page writeback */
1571	if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
1572		f2fs_wait_on_encrypted_page_writeback(sbi, blkaddr);
1573
1574	if (len == PAGE_SIZE)
1575		goto out_update;
1576	if (PageUptodate(page))
1577		goto out_clear;
1578
1579	if ((pos & PAGE_MASK) >= i_size_read(inode)) {
1580		unsigned start = pos & (PAGE_SIZE - 1);
1581		unsigned end = start + len;
1582
1583		/* Reading beyond i_size is simple: memset to zero */
1584		zero_user_segments(page, 0, start, end, PAGE_SIZE);
1585		goto out_update;
1586	}
1587
1588	if (blkaddr == NEW_ADDR) {
1589		zero_user_segment(page, 0, PAGE_SIZE);
1590	} else {
1591		struct f2fs_io_info fio = {
1592			.sbi = sbi,
1593			.type = DATA,
1594			.rw = READ_SYNC,
1595			.old_blkaddr = blkaddr,
1596			.new_blkaddr = blkaddr,
1597			.page = page,
1598			.encrypted_page = NULL,
1599		};
1600		err = f2fs_submit_page_bio(&fio);
1601		if (err)
1602			goto fail;
1603
1604		lock_page(page);
1605		if (unlikely(!PageUptodate(page))) {
1606			err = -EIO;
1607			goto fail;
1608		}
1609		if (unlikely(page->mapping != mapping)) {
1610			f2fs_put_page(page, 1);
1611			goto repeat;
1612		}
1613
1614		/* avoid symlink page */
1615		if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
1616			err = fscrypt_decrypt_page(page);
1617			if (err)
1618				goto fail;
1619		}
1620	}
1621out_update:
1622	SetPageUptodate(page);
1623out_clear:
1624	clear_cold_data(page);
1625	return 0;
1626
1627fail:
1628	f2fs_put_page(page, 1);
1629	f2fs_write_failed(mapping, pos + len);
1630	return err;
1631}
1632
1633static int f2fs_write_end(struct file *file,
1634			struct address_space *mapping,
1635			loff_t pos, unsigned len, unsigned copied,
1636			struct page *page, void *fsdata)
1637{
1638	struct inode *inode = page->mapping->host;
1639
1640	trace_f2fs_write_end(inode, pos, len, copied);
1641
1642	set_page_dirty(page);
1643
1644	if (pos + copied > i_size_read(inode)) {
1645		i_size_write(inode, pos + copied);
1646		mark_inode_dirty(inode);
1647	}
1648
1649	f2fs_put_page(page, 1);
1650	f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
1651	return copied;
1652}
1653
1654static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
1655			   loff_t offset)
1656{
1657	unsigned blocksize_mask = inode->i_sb->s_blocksize - 1;
1658
1659	if (offset & blocksize_mask)
1660		return -EINVAL;
1661
1662	if (iov_iter_alignment(iter) & blocksize_mask)
1663		return -EINVAL;
1664
1665	return 0;
1666}
1667
1668static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
1669			      loff_t offset)
1670{
1671	struct address_space *mapping = iocb->ki_filp->f_mapping;
1672	struct inode *inode = mapping->host;
1673	size_t count = iov_iter_count(iter);
1674	int err;
1675
1676	err = check_direct_IO(inode, iter, offset);
1677	if (err)
1678		return err;
1679
1680	if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
1681		return 0;
1682
1683	trace_f2fs_direct_IO_enter(inode, offset, count, iov_iter_rw(iter));
1684
1685	err = blockdev_direct_IO(iocb, inode, iter, offset, get_data_block_dio);
1686	if (err < 0 && iov_iter_rw(iter) == WRITE)
1687		f2fs_write_failed(mapping, offset + count);
1688
1689	trace_f2fs_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), err);
1690
1691	return err;
1692}
1693
1694void f2fs_invalidate_page(struct page *page, unsigned int offset,
1695							unsigned int length)
1696{
1697	struct inode *inode = page->mapping->host;
1698	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1699
1700	if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
1701		(offset % PAGE_SIZE || length != PAGE_SIZE))
1702		return;
1703
1704	if (PageDirty(page)) {
1705		if (inode->i_ino == F2FS_META_INO(sbi))
1706			dec_page_count(sbi, F2FS_DIRTY_META);
1707		else if (inode->i_ino == F2FS_NODE_INO(sbi))
1708			dec_page_count(sbi, F2FS_DIRTY_NODES);
1709		else
1710			inode_dec_dirty_pages(inode);
1711	}
1712
1713	/* This is atomic written page, keep Private */
1714	if (IS_ATOMIC_WRITTEN_PAGE(page))
1715		return;
1716
1717	ClearPagePrivate(page);
1718}
1719
1720int f2fs_release_page(struct page *page, gfp_t wait)
1721{
1722	/* If this is dirty page, keep PagePrivate */
1723	if (PageDirty(page))
1724		return 0;
1725
1726	/* This is atomic written page, keep Private */
1727	if (IS_ATOMIC_WRITTEN_PAGE(page))
1728		return 0;
1729
1730	ClearPagePrivate(page);
1731	return 1;
1732}
1733
1734static int f2fs_set_data_page_dirty(struct page *page)
1735{
1736	struct address_space *mapping = page->mapping;
1737	struct inode *inode = mapping->host;
1738
1739	trace_f2fs_set_page_dirty(page, DATA);
1740
1741	SetPageUptodate(page);
1742
1743	if (f2fs_is_atomic_file(inode)) {
1744		if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
1745			register_inmem_page(inode, page);
1746			return 1;
1747		}
1748		/*
1749		 * Previously, this page has been registered, we just
1750		 * return here.
1751		 */
1752		return 0;
1753	}
1754
1755	if (!PageDirty(page)) {
1756		__set_page_dirty_nobuffers(page);
1757		update_dirty_page(inode, page);
1758		return 1;
1759	}
1760	return 0;
1761}
1762
1763static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
1764{
1765	struct inode *inode = mapping->host;
1766
1767	if (f2fs_has_inline_data(inode))
1768		return 0;
1769
1770	/* make sure allocating whole blocks */
1771	if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
1772		filemap_write_and_wait(mapping);
1773
1774	return generic_block_bmap(mapping, block, get_data_block_bmap);
1775}
1776
1777const struct address_space_operations f2fs_dblock_aops = {
1778	.readpage	= f2fs_read_data_page,
1779	.readpages	= f2fs_read_data_pages,
1780	.writepage	= f2fs_write_data_page,
1781	.writepages	= f2fs_write_data_pages,
1782	.write_begin	= f2fs_write_begin,
1783	.write_end	= f2fs_write_end,
1784	.set_page_dirty	= f2fs_set_data_page_dirty,
1785	.invalidatepage	= f2fs_invalidate_page,
1786	.releasepage	= f2fs_release_page,
1787	.direct_IO	= f2fs_direct_IO,
1788	.bmap		= f2fs_bmap,
1789};