Commit 6311f91f authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Linus Torvalds
Browse files

ext4: convert from readpages to readahead 



Use the new readahead operation in ext4

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarWilliam Kucharski <william.kucharski@oracle.com>
Reviewed-by: default avatarEric Biggers <ebiggers@google.com>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Gao Xiang <gaoxiang25@huawei.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Link: http://lkml.kernel.org/r/20200414150233.24495-21-willy@infradead.org


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 0615090c

fs/ext4/ext4.h

+1 −2
Original line number Diff line number Diff line
@@ -3318,8 +3318,7 @@ static inline void ext4_set_de_type(struct super_block *sb, 


/* readpages.c */

extern int ext4_mpage_readpages(struct address_space *mapping,

				struct list_head *pages, struct page *page,

				unsigned nr_pages, bool is_readahead);

		struct readahead_control *rac, struct page *page);

extern int __init ext4_init_post_read_processing(void);

extern void ext4_exit_post_read_processing(void);

fs/ext4/inode.c

+9 −12
Original line number Diff line number Diff line
@@ -3224,23 +3224,20 @@ static int ext4_readpage(struct file *file, struct page *page) 
		ret = ext4_readpage_inline(inode, page);



	if (ret == -EAGAIN)

		return ext4_mpage_readpages(page->mapping, NULL, page, 1,

						false);

		return ext4_mpage_readpages(page->mapping, NULL, page);



	return ret;

}



static int

ext4_readpages(struct file *file, struct address_space *mapping,

		struct list_head *pages, unsigned nr_pages)

static void ext4_readahead(struct readahead_control *rac)

{

	struct inode *inode = mapping->host;

	struct inode *inode = rac->mapping->host;



	/* If the file has inline data, no need to do readpages. */

	/* If the file has inline data, no need to do readahead. */

	if (ext4_has_inline_data(inode))

		return 0;

		return;



	return ext4_mpage_readpages(mapping, pages, NULL, nr_pages, true);

	ext4_mpage_readpages(rac->mapping, rac, NULL);

}



static void ext4_invalidatepage(struct page *page, unsigned int offset,
@@ -3605,7 +3602,7 @@ static int ext4_set_page_dirty(struct page *page) 


static const struct address_space_operations ext4_aops = {

	.readpage		= ext4_readpage,

	.readpages		= ext4_readpages,

	.readahead		= ext4_readahead,

	.writepage		= ext4_writepage,

	.writepages		= ext4_writepages,

	.write_begin		= ext4_write_begin,
@@ -3622,7 +3619,7 @@ static const struct address_space_operations ext4_aops = { 


static const struct address_space_operations ext4_journalled_aops = {

	.readpage		= ext4_readpage,

	.readpages		= ext4_readpages,

	.readahead		= ext4_readahead,

	.writepage		= ext4_writepage,

	.writepages		= ext4_writepages,

	.write_begin		= ext4_write_begin,
@@ -3638,7 +3635,7 @@ static const struct address_space_operations ext4_journalled_aops = { 


static const struct address_space_operations ext4_da_aops = {

	.readpage		= ext4_readpage,

	.readpages		= ext4_readpages,

	.readahead		= ext4_readahead,

	.writepage		= ext4_writepage,

	.writepages		= ext4_writepages,

	.write_begin		= ext4_da_write_begin,

fs/ext4/readpage.c

+8 −14
Original line number Diff line number Diff line
@@ -7,8 +7,8 @@ 
 *

 * This was originally taken from fs/mpage.c

 *

 * The intent is the ext4_mpage_readpages() function here is intended

 * to replace mpage_readpages() in the general case, not just for

 * The ext4_mpage_readpages() function here is intended to

 * replace mpage_readahead() in the general case, not just for

 * encrypted files.  It has some limitations (see below), where it

 * will fall back to read_block_full_page(), but these limitations

 * should only be hit when page_size != block_size.
@@ -222,8 +222,7 @@ static inline loff_t ext4_readpage_limit(struct inode *inode) 
}



int ext4_mpage_readpages(struct address_space *mapping,

			 struct list_head *pages, struct page *page,

			 unsigned nr_pages, bool is_readahead)

		struct readahead_control *rac, struct page *page)

{

	struct bio *bio = NULL;

	sector_t last_block_in_bio = 0;
@@ -241,6 +240,7 @@ int ext4_mpage_readpages(struct address_space *mapping, 
	int length;

	unsigned relative_block = 0;

	struct ext4_map_blocks map;

	unsigned int nr_pages = rac ? readahead_count(rac) : 1;



	map.m_pblk = 0;

	map.m_lblk = 0;
@@ -251,14 +251,9 @@ int ext4_mpage_readpages(struct address_space *mapping, 
		int fully_mapped = 1;

		unsigned first_hole = blocks_per_page;



		if (pages) {

			page = lru_to_page(pages);



		if (rac) {

			page = readahead_page(rac);

			prefetchw(&page->flags);

			list_del(&page->lru);

			if (add_to_page_cache_lru(page, mapping, page->index,

				  readahead_gfp_mask(mapping)))

				goto next_page;

		}



		if (page_has_buffers(page))
@@ -381,7 +376,7 @@ int ext4_mpage_readpages(struct address_space *mapping, 
			bio->bi_iter.bi_sector = blocks[0] << (blkbits - 9);

			bio->bi_end_io = mpage_end_io;

			bio_set_op_attrs(bio, REQ_OP_READ,

						is_readahead ? REQ_RAHEAD : 0);

						rac ? REQ_RAHEAD : 0);

		}



		length = first_hole << blkbits;
@@ -406,10 +401,9 @@ int ext4_mpage_readpages(struct address_space *mapping, 
		else

			unlock_page(page);

	next_page:

		if (pages)

		if (rac)

			put_page(page);

	}

	BUG_ON(pages && !list_empty(pages));

	if (bio)

		submit_bio(bio);

	return 0;

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