Commit 38aa0889 authored by Jaegeuk Kim's avatar Jaegeuk Kim
Browse files

f2fs: align direct_io'ed data to section 



This patch aligns the start block address of a file for direct io to the f2fs's
section size.

Some flash devices manage an over 4KB-sized page as a write unit, and if the
direct_io'ed data are written but not aligned to that unit, the performance can
be degraded due to the partial page copies.

Thus, since f2fs has a section that is well aligned to FTL units, we can align
the block address to the section size so that f2fs avoids this misalignment.

Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 41ef94b3

fs/f2fs/data.c

+5 −2
Original line number Diff line number Diff line
@@ -564,6 +564,7 @@ static int __allocate_data_block(struct dnode_of_data *dn) 
	struct f2fs_inode_info *fi = F2FS_I(dn->inode);

	struct f2fs_summary sum;

	struct node_info ni;

	int seg = CURSEG_WARM_DATA;

	pgoff_t fofs;



	if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
@@ -574,8 +575,10 @@ static int __allocate_data_block(struct dnode_of_data *dn) 
	get_node_info(sbi, dn->nid, &ni);

	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);



	allocate_data_block(sbi, NULL, NULL_ADDR, &dn->data_blkaddr, &sum,

							CURSEG_WARM_DATA);

	if (dn->ofs_in_node == 0 && dn->inode_page == dn->node_page)

		seg = CURSEG_DIRECT_IO;



	allocate_data_block(sbi, NULL, NULL_ADDR, &dn->data_blkaddr, &sum, seg);



	/* direct IO doesn't use extent cache to maximize the performance */

	__set_data_blkaddr(dn);

fs/f2fs/f2fs.h

+2 −1
Original line number Diff line number Diff line
@@ -406,7 +406,8 @@ enum { 
	CURSEG_HOT_NODE,	/* direct node blocks of directory files */

	CURSEG_WARM_NODE,	/* direct node blocks of normal files */

	CURSEG_COLD_NODE,	/* indirect node blocks */

	NO_CHECK_TYPE

	NO_CHECK_TYPE,

	CURSEG_DIRECT_IO,	/* to use for the direct IO path */

};



struct flush_cmd {

fs/f2fs/segment.c

+19 −8
Original line number Diff line number Diff line
@@ -1024,18 +1024,22 @@ static void allocate_segment_by_default(struct f2fs_sb_info *sbi, 
	stat_inc_seg_type(sbi, curseg);

}



static void __allocate_new_segments(struct f2fs_sb_info *sbi, int type)

{

	struct curseg_info *curseg = CURSEG_I(sbi, type);

	unsigned int old_segno;



	old_segno = curseg->segno;

	SIT_I(sbi)->s_ops->allocate_segment(sbi, type, true);

	locate_dirty_segment(sbi, old_segno);

}



void allocate_new_segments(struct f2fs_sb_info *sbi)

{

	struct curseg_info *curseg;

	unsigned int old_curseg;

	int i;



	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {

		curseg = CURSEG_I(sbi, i);

		old_curseg = curseg->segno;

		SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);

		locate_dirty_segment(sbi, old_curseg);

	}

	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++)

		__allocate_new_segments(sbi, i);

}



static const struct segment_allocation default_salloc_ops = {
@@ -1148,11 +1152,18 @@ void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page, 
{

	struct sit_info *sit_i = SIT_I(sbi);

	struct curseg_info *curseg;

	bool direct_io = (type == CURSEG_DIRECT_IO);



	type = direct_io ? CURSEG_WARM_DATA : type;



	curseg = CURSEG_I(sbi, type);



	mutex_lock(&curseg->curseg_mutex);



	/* direct_io'ed data is aligned to the segment for better performance */

	if (direct_io && curseg->next_blkoff)

		__allocate_new_segments(sbi, type);



	*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);



	/*

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