Commit 4cb03fec authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Jaegeuk Kim
Browse files

f2fs: Simplify SEEK_DATA implementation 



Instead of finding the first dirty page and then seeing if it matches
the index of a block that is NEW_ADDR, delay the lookup of the dirty
bit until we've actually found a block that's NEW_ADDR.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 093749e2

fs/f2fs/file.c

+8 −27
Original line number Diff line number Diff line
@@ -376,32 +376,15 @@ int f2fs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) 
	return f2fs_do_sync_file(file, start, end, datasync, false);

}



static pgoff_t __get_first_dirty_index(struct address_space *mapping,

						pgoff_t pgofs, int whence)

{

	struct page *page;

	int nr_pages;



	if (whence != SEEK_DATA)

		return 0;



	/* find first dirty page index */

	nr_pages = find_get_pages_tag(mapping, &pgofs, PAGECACHE_TAG_DIRTY,

				      1, &page);

	if (!nr_pages)

		return ULONG_MAX;

	pgofs = page->index;

	put_page(page);

	return pgofs;

}



static bool __found_offset(struct f2fs_sb_info *sbi, block_t blkaddr,

				pgoff_t dirty, pgoff_t pgofs, int whence)

static bool __found_offset(struct address_space *mapping, block_t blkaddr,

				pgoff_t index, int whence)

{

	switch (whence) {

	case SEEK_DATA:

		if ((blkaddr == NEW_ADDR && dirty == pgofs) ||

			__is_valid_data_blkaddr(blkaddr))

		if (__is_valid_data_blkaddr(blkaddr))

			return true;

		if (blkaddr == NEW_ADDR &&

		    xa_get_mark(&mapping->i_pages, index, PAGECACHE_TAG_DIRTY))

			return true;

		break;

	case SEEK_HOLE:
@@ -417,7 +400,7 @@ static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence) 
	struct inode *inode = file->f_mapping->host;

	loff_t maxbytes = inode->i_sb->s_maxbytes;

	struct dnode_of_data dn;

	pgoff_t pgofs, end_offset, dirty;

	pgoff_t pgofs, end_offset;

	loff_t data_ofs = offset;

	loff_t isize;

	int err = 0;
@@ -437,8 +420,6 @@ static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence) 


	pgofs = (pgoff_t)(offset >> PAGE_SHIFT);



	dirty = __get_first_dirty_index(inode->i_mapping, pgofs, whence);



	for (; data_ofs < isize; data_ofs = (loff_t)pgofs << PAGE_SHIFT) {

		set_new_dnode(&dn, inode, NULL, NULL, 0);

		err = f2fs_get_dnode_of_data(&dn, pgofs, LOOKUP_NODE);
@@ -471,7 +452,7 @@ static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence) 
				goto fail;

			}



			if (__found_offset(F2FS_I_SB(inode), blkaddr, dirty,

			if (__found_offset(file->f_mapping, blkaddr,

							pgofs, whence)) {

				f2fs_put_dnode(&dn);

				goto found;