4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
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.
12 #include <linux/f2fs_fs.h>
13 #include <linux/buffer_head.h>
14 #include <linux/mpage.h>
15 #include <linux/aio.h>
16 #include <linux/writeback.h>
17 #include <linux/backing-dev.h>
18 #include <linux/blkdev.h>
19 #include <linux/bio.h>
20 #include <linux/prefetch.h>
25 #include <trace/events/f2fs.h>
28 * Lock ordering for the change of data block address:
31 * update block addresses in the node page
33 static void __set_data_blkaddr(struct dnode_of_data *dn, block_t new_addr)
37 struct page *node_page = dn->node_page;
38 unsigned int ofs_in_node = dn->ofs_in_node;
40 f2fs_wait_on_page_writeback(node_page, NODE, false);
42 rn = F2FS_NODE(node_page);
44 /* Get physical address of data block */
45 addr_array = blkaddr_in_node(rn);
46 addr_array[ofs_in_node] = cpu_to_le32(new_addr);
47 set_page_dirty(node_page);
50 int reserve_new_block(struct dnode_of_data *dn)
52 struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
54 if (is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC))
56 if (!inc_valid_block_count(sbi, dn->inode, 1))
59 trace_f2fs_reserve_new_block(dn->inode, dn->nid, dn->ofs_in_node);
61 __set_data_blkaddr(dn, NEW_ADDR);
62 dn->data_blkaddr = NEW_ADDR;
67 static int check_extent_cache(struct inode *inode, pgoff_t pgofs,
68 struct buffer_head *bh_result)
70 struct f2fs_inode_info *fi = F2FS_I(inode);
71 pgoff_t start_fofs, end_fofs;
72 block_t start_blkaddr;
74 read_lock(&fi->ext.ext_lock);
75 if (fi->ext.len == 0) {
76 read_unlock(&fi->ext.ext_lock);
80 stat_inc_total_hit(inode->i_sb);
82 start_fofs = fi->ext.fofs;
83 end_fofs = fi->ext.fofs + fi->ext.len - 1;
84 start_blkaddr = fi->ext.blk_addr;
86 if (pgofs >= start_fofs && pgofs <= end_fofs) {
87 unsigned int blkbits = inode->i_sb->s_blocksize_bits;
90 clear_buffer_new(bh_result);
91 map_bh(bh_result, inode->i_sb,
92 start_blkaddr + pgofs - start_fofs);
93 count = end_fofs - pgofs + 1;
94 if (count < (UINT_MAX >> blkbits))
95 bh_result->b_size = (count << blkbits);
97 bh_result->b_size = UINT_MAX;
99 stat_inc_read_hit(inode->i_sb);
100 read_unlock(&fi->ext.ext_lock);
103 read_unlock(&fi->ext.ext_lock);
107 void update_extent_cache(block_t blk_addr, struct dnode_of_data *dn)
109 struct f2fs_inode_info *fi = F2FS_I(dn->inode);
110 pgoff_t fofs, start_fofs, end_fofs;
111 block_t start_blkaddr, end_blkaddr;
113 f2fs_bug_on(blk_addr == NEW_ADDR);
114 fofs = start_bidx_of_node(ofs_of_node(dn->node_page), fi) +
117 /* Update the page address in the parent node */
118 __set_data_blkaddr(dn, blk_addr);
120 write_lock(&fi->ext.ext_lock);
122 start_fofs = fi->ext.fofs;
123 end_fofs = fi->ext.fofs + fi->ext.len - 1;
124 start_blkaddr = fi->ext.blk_addr;
125 end_blkaddr = fi->ext.blk_addr + fi->ext.len - 1;
127 /* Drop and initialize the matched extent */
128 if (fi->ext.len == 1 && fofs == start_fofs)
132 if (fi->ext.len == 0) {
133 if (blk_addr != NULL_ADDR) {
135 fi->ext.blk_addr = blk_addr;
142 if (fofs == start_fofs - 1 && blk_addr == start_blkaddr - 1) {
150 if (fofs == end_fofs + 1 && blk_addr == end_blkaddr + 1) {
155 /* Split the existing extent */
156 if (fi->ext.len > 1 &&
157 fofs >= start_fofs && fofs <= end_fofs) {
158 if ((end_fofs - fofs) < (fi->ext.len >> 1)) {
159 fi->ext.len = fofs - start_fofs;
161 fi->ext.fofs = fofs + 1;
162 fi->ext.blk_addr = start_blkaddr +
163 fofs - start_fofs + 1;
164 fi->ext.len -= fofs - start_fofs + 1;
168 write_unlock(&fi->ext.ext_lock);
172 write_unlock(&fi->ext.ext_lock);
176 struct page *find_data_page(struct inode *inode, pgoff_t index, bool sync)
178 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
179 struct address_space *mapping = inode->i_mapping;
180 struct dnode_of_data dn;
184 page = find_get_page(mapping, index);
185 if (page && PageUptodate(page))
187 f2fs_put_page(page, 0);
189 set_new_dnode(&dn, inode, NULL, NULL, 0);
190 err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
195 if (dn.data_blkaddr == NULL_ADDR)
196 return ERR_PTR(-ENOENT);
198 /* By fallocate(), there is no cached page, but with NEW_ADDR */
199 if (dn.data_blkaddr == NEW_ADDR)
200 return ERR_PTR(-EINVAL);
202 page = grab_cache_page_write_begin(mapping, index, AOP_FLAG_NOFS);
204 return ERR_PTR(-ENOMEM);
206 if (PageUptodate(page)) {
211 err = f2fs_readpage(sbi, page, dn.data_blkaddr,
212 sync ? READ_SYNC : READA);
214 wait_on_page_locked(page);
215 if (!PageUptodate(page)) {
216 f2fs_put_page(page, 0);
217 return ERR_PTR(-EIO);
224 * If it tries to access a hole, return an error.
225 * Because, the callers, functions in dir.c and GC, should be able to know
226 * whether this page exists or not.
228 struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
230 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
231 struct address_space *mapping = inode->i_mapping;
232 struct dnode_of_data dn;
237 page = grab_cache_page_write_begin(mapping, index, AOP_FLAG_NOFS);
239 return ERR_PTR(-ENOMEM);
241 set_new_dnode(&dn, inode, NULL, NULL, 0);
242 err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
244 f2fs_put_page(page, 1);
249 if (dn.data_blkaddr == NULL_ADDR) {
250 f2fs_put_page(page, 1);
251 return ERR_PTR(-ENOENT);
254 if (PageUptodate(page))
258 * A new dentry page is allocated but not able to be written, since its
259 * new inode page couldn't be allocated due to -ENOSPC.
260 * In such the case, its blkaddr can be remained as NEW_ADDR.
261 * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
263 if (dn.data_blkaddr == NEW_ADDR) {
264 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
265 SetPageUptodate(page);
269 err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
274 if (!PageUptodate(page)) {
275 f2fs_put_page(page, 1);
276 return ERR_PTR(-EIO);
278 if (page->mapping != mapping) {
279 f2fs_put_page(page, 1);
286 * Caller ensures that this data page is never allocated.
287 * A new zero-filled data page is allocated in the page cache.
289 * Also, caller should grab and release a mutex by calling mutex_lock_op() and
291 * Note that, npage is set only by make_empty_dir.
293 struct page *get_new_data_page(struct inode *inode,
294 struct page *npage, pgoff_t index, bool new_i_size)
296 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
297 struct address_space *mapping = inode->i_mapping;
299 struct dnode_of_data dn;
302 set_new_dnode(&dn, inode, npage, npage, 0);
303 err = get_dnode_of_data(&dn, index, ALLOC_NODE);
307 if (dn.data_blkaddr == NULL_ADDR) {
308 if (reserve_new_block(&dn)) {
311 return ERR_PTR(-ENOSPC);
317 page = grab_cache_page(mapping, index);
319 return ERR_PTR(-ENOMEM);
321 if (PageUptodate(page))
324 if (dn.data_blkaddr == NEW_ADDR) {
325 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
326 SetPageUptodate(page);
328 err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
332 if (!PageUptodate(page)) {
333 f2fs_put_page(page, 1);
334 return ERR_PTR(-EIO);
336 if (page->mapping != mapping) {
337 f2fs_put_page(page, 1);
343 i_size_read(inode) < ((index + 1) << PAGE_CACHE_SHIFT)) {
344 i_size_write(inode, ((index + 1) << PAGE_CACHE_SHIFT));
345 /* Only the directory inode sets new_i_size */
346 set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR);
347 mark_inode_dirty_sync(inode);
352 static void read_end_io(struct bio *bio, int err)
354 struct bio_vec *bvec;
357 bio_for_each_segment_all(bvec, bio, i) {
358 struct page *page = bvec->bv_page;
361 SetPageUptodate(page);
363 ClearPageUptodate(page);
372 * Fill the locked page with data located in the block address.
373 * Return unlocked page.
375 int f2fs_readpage(struct f2fs_sb_info *sbi, struct page *page,
376 block_t blk_addr, int type)
378 struct block_device *bdev = sbi->sb->s_bdev;
381 trace_f2fs_readpage(page, blk_addr, type);
383 down_read(&sbi->bio_sem);
385 /* Allocate a new bio */
386 bio = f2fs_bio_alloc(bdev, 1);
388 /* Initialize the bio */
389 bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(sbi, blk_addr);
390 bio->bi_end_io = read_end_io;
392 if (bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) < PAGE_CACHE_SIZE) {
394 up_read(&sbi->bio_sem);
395 f2fs_put_page(page, 1);
399 submit_bio(type, bio);
400 up_read(&sbi->bio_sem);
405 * This function should be used by the data read flow only where it
406 * does not check the "create" flag that indicates block allocation.
407 * The reason for this special functionality is to exploit VFS readahead
410 static int get_data_block_ro(struct inode *inode, sector_t iblock,
411 struct buffer_head *bh_result, int create)
413 unsigned int blkbits = inode->i_sb->s_blocksize_bits;
414 unsigned maxblocks = bh_result->b_size >> blkbits;
415 struct dnode_of_data dn;
419 /* Get the page offset from the block offset(iblock) */
420 pgofs = (pgoff_t)(iblock >> (PAGE_CACHE_SHIFT - blkbits));
422 if (check_extent_cache(inode, pgofs, bh_result)) {
423 trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
427 /* When reading holes, we need its node page */
428 set_new_dnode(&dn, inode, NULL, NULL, 0);
429 err = get_dnode_of_data(&dn, pgofs, LOOKUP_NODE_RA);
431 trace_f2fs_get_data_block(inode, iblock, bh_result, err);
432 return (err == -ENOENT) ? 0 : err;
435 /* It does not support data allocation */
438 if (dn.data_blkaddr != NEW_ADDR && dn.data_blkaddr != NULL_ADDR) {
440 unsigned int end_offset;
442 end_offset = IS_INODE(dn.node_page) ?
443 ADDRS_PER_INODE(F2FS_I(inode)) :
446 clear_buffer_new(bh_result);
448 /* Give more consecutive addresses for the read ahead */
449 for (i = 0; i < end_offset - dn.ofs_in_node; i++)
450 if (((datablock_addr(dn.node_page,
452 != (dn.data_blkaddr + i)) || maxblocks == i)
454 map_bh(bh_result, inode->i_sb, dn.data_blkaddr);
455 bh_result->b_size = (i << blkbits);
458 trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
462 static int f2fs_read_data_page(struct file *file, struct page *page)
464 return mpage_readpage(page, get_data_block_ro);
467 static int f2fs_read_data_pages(struct file *file,
468 struct address_space *mapping,
469 struct list_head *pages, unsigned nr_pages)
471 return mpage_readpages(mapping, pages, nr_pages, get_data_block_ro);
474 int do_write_data_page(struct page *page)
476 struct inode *inode = page->mapping->host;
477 block_t old_blk_addr, new_blk_addr;
478 struct dnode_of_data dn;
481 set_new_dnode(&dn, inode, NULL, NULL, 0);
482 err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
486 old_blk_addr = dn.data_blkaddr;
488 /* This page is already truncated */
489 if (old_blk_addr == NULL_ADDR)
492 set_page_writeback(page);
495 * If current allocation needs SSR,
496 * it had better in-place writes for updated data.
498 if (unlikely(old_blk_addr != NEW_ADDR &&
499 !is_cold_data(page) &&
500 need_inplace_update(inode))) {
501 rewrite_data_page(F2FS_SB(inode->i_sb), page,
504 write_data_page(inode, page, &dn,
505 old_blk_addr, &new_blk_addr);
506 update_extent_cache(new_blk_addr, &dn);
513 static int f2fs_write_data_page(struct page *page,
514 struct writeback_control *wbc)
516 struct inode *inode = page->mapping->host;
517 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
518 loff_t i_size = i_size_read(inode);
519 const pgoff_t end_index = ((unsigned long long) i_size)
522 bool need_balance_fs = false;
525 if (page->index < end_index)
529 * If the offset is out-of-range of file size,
530 * this page does not have to be written to disk.
532 offset = i_size & (PAGE_CACHE_SIZE - 1);
533 if ((page->index >= end_index + 1) || !offset) {
534 if (S_ISDIR(inode->i_mode)) {
535 dec_page_count(sbi, F2FS_DIRTY_DENTS);
536 inode_dec_dirty_dents(inode);
541 zero_user_segment(page, offset, PAGE_CACHE_SIZE);
543 if (sbi->por_doing) {
544 err = AOP_WRITEPAGE_ACTIVATE;
548 /* Dentry blocks are controlled by checkpoint */
549 if (S_ISDIR(inode->i_mode)) {
550 dec_page_count(sbi, F2FS_DIRTY_DENTS);
551 inode_dec_dirty_dents(inode);
552 err = do_write_data_page(page);
555 err = do_write_data_page(page);
557 need_balance_fs = true;
564 if (wbc->for_reclaim)
565 f2fs_submit_bio(sbi, DATA, true);
567 clear_cold_data(page);
571 f2fs_balance_fs(sbi);
575 wbc->pages_skipped++;
576 set_page_dirty(page);
580 #define MAX_DESIRED_PAGES_WP 4096
582 static int __f2fs_writepage(struct page *page, struct writeback_control *wbc,
585 struct address_space *mapping = data;
586 int ret = mapping->a_ops->writepage(page, wbc);
587 mapping_set_error(mapping, ret);
591 static int f2fs_write_data_pages(struct address_space *mapping,
592 struct writeback_control *wbc)
594 struct inode *inode = mapping->host;
595 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
598 long excess_nrtw = 0, desired_nrtw;
600 /* deal with chardevs and other special file */
601 if (!mapping->a_ops->writepage)
604 if (wbc->nr_to_write < MAX_DESIRED_PAGES_WP) {
605 desired_nrtw = MAX_DESIRED_PAGES_WP;
606 excess_nrtw = desired_nrtw - wbc->nr_to_write;
607 wbc->nr_to_write = desired_nrtw;
610 if (!S_ISDIR(inode->i_mode)) {
611 mutex_lock(&sbi->writepages);
614 ret = write_cache_pages(mapping, wbc, __f2fs_writepage, mapping);
616 mutex_unlock(&sbi->writepages);
617 f2fs_submit_bio(sbi, DATA, (wbc->sync_mode == WB_SYNC_ALL));
619 remove_dirty_dir_inode(inode);
621 wbc->nr_to_write -= excess_nrtw;
625 static int f2fs_write_begin(struct file *file, struct address_space *mapping,
626 loff_t pos, unsigned len, unsigned flags,
627 struct page **pagep, void **fsdata)
629 struct inode *inode = mapping->host;
630 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
632 pgoff_t index = ((unsigned long long) pos) >> PAGE_CACHE_SHIFT;
633 struct dnode_of_data dn;
636 f2fs_balance_fs(sbi);
638 page = grab_cache_page_write_begin(mapping, index, flags);
645 set_new_dnode(&dn, inode, NULL, NULL, 0);
646 err = get_dnode_of_data(&dn, index, ALLOC_NODE);
650 if (dn.data_blkaddr == NULL_ADDR)
651 err = reserve_new_block(&dn);
659 if ((len == PAGE_CACHE_SIZE) || PageUptodate(page))
662 if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
663 unsigned start = pos & (PAGE_CACHE_SIZE - 1);
664 unsigned end = start + len;
666 /* Reading beyond i_size is simple: memset to zero */
667 zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
671 if (dn.data_blkaddr == NEW_ADDR) {
672 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
674 err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
678 if (!PageUptodate(page)) {
679 f2fs_put_page(page, 1);
682 if (page->mapping != mapping) {
683 f2fs_put_page(page, 1);
688 SetPageUptodate(page);
689 clear_cold_data(page);
694 f2fs_put_page(page, 1);
698 static int f2fs_write_end(struct file *file,
699 struct address_space *mapping,
700 loff_t pos, unsigned len, unsigned copied,
701 struct page *page, void *fsdata)
703 struct inode *inode = page->mapping->host;
705 SetPageUptodate(page);
706 set_page_dirty(page);
708 if (pos + copied > i_size_read(inode)) {
709 i_size_write(inode, pos + copied);
710 mark_inode_dirty(inode);
711 update_inode_page(inode);
715 page_cache_release(page);
719 static ssize_t f2fs_direct_IO(int rw, struct kiocb *iocb,
720 const struct iovec *iov, loff_t offset, unsigned long nr_segs)
722 struct file *file = iocb->ki_filp;
723 struct inode *inode = file->f_mapping->host;
728 /* Needs synchronization with the cleaner */
729 return blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
733 static void f2fs_invalidate_data_page(struct page *page, unsigned int offset,
736 struct inode *inode = page->mapping->host;
737 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
738 if (S_ISDIR(inode->i_mode) && PageDirty(page)) {
739 dec_page_count(sbi, F2FS_DIRTY_DENTS);
740 inode_dec_dirty_dents(inode);
742 ClearPagePrivate(page);
745 static int f2fs_release_data_page(struct page *page, gfp_t wait)
747 ClearPagePrivate(page);
751 static int f2fs_set_data_page_dirty(struct page *page)
753 struct address_space *mapping = page->mapping;
754 struct inode *inode = mapping->host;
756 trace_f2fs_set_page_dirty(page, DATA);
758 SetPageUptodate(page);
759 if (!PageDirty(page)) {
760 __set_page_dirty_nobuffers(page);
761 set_dirty_dir_page(inode, page);
767 static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
769 return generic_block_bmap(mapping, block, get_data_block_ro);
772 const struct address_space_operations f2fs_dblock_aops = {
773 .readpage = f2fs_read_data_page,
774 .readpages = f2fs_read_data_pages,
775 .writepage = f2fs_write_data_page,
776 .writepages = f2fs_write_data_pages,
777 .write_begin = f2fs_write_begin,
778 .write_end = f2fs_write_end,
779 .set_page_dirty = f2fs_set_data_page_dirty,
780 .invalidatepage = f2fs_invalidate_data_page,
781 .releasepage = f2fs_release_data_page,
782 .direct_IO = f2fs_direct_IO,