f2fs: add ioctl to flush data from faster device to cold area

This patch adds an ioctl to flush data in faster device to cold area. User can
give device number and number of segments to move. It doesn't move it if there
is only one device.

The parameter looks like:

struct f2fs_flush_device {
	u32 dev_num;		/* device number to flush */
	u32 segments;		/* # of segments to flush */
};

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 10 insertions, 4 deletions

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index dd07c5c91ac4..1b16770f9d2e 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -401,7 +401,7 @@ void f2fs_balance_fs(struct f2fs_sb_info *sbi, bool need)
 	 */
 	if (has_not_enough_free_secs(sbi, 0, 0)) {
 		mutex_lock(&sbi->gc_mutex);
-		f2fs_gc(sbi, false, false);
+		f2fs_gc(sbi, false, false, NULL_SEGNO);
 	}
 }
 
@@ -1755,6 +1755,8 @@ static unsigned int __get_next_segno(struct f2fs_sb_info *sbi, int type)
 	if (type == CURSEG_HOT_DATA || IS_NODESEG(type))
 		return 0;
 
+	if (SIT_I(sbi)->last_victim[ALLOC_NEXT])
+		return SIT_I(sbi)->last_victim[ALLOC_NEXT];
 	return CURSEG_I(sbi, type)->segno;
 }
 
@@ -1852,12 +1854,15 @@ static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
 {
 	struct curseg_info *curseg = CURSEG_I(sbi, type);
 	const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
+	unsigned segno = NULL_SEGNO;
 	int i, cnt;
 	bool reversed = false;
 
 	/* need_SSR() already forces to do this */
-	if (v_ops->get_victim(sbi, &(curseg)->next_segno, BG_GC, type, SSR))
+	if (v_ops->get_victim(sbi, &segno, BG_GC, type, SSR)) {
+		curseg->next_segno = segno;
 		return 1;
+	}
 
 	/* For node segments, let's do SSR more intensively */
 	if (IS_NODESEG(type)) {
@@ -1881,9 +1886,10 @@ static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
 	for (; cnt-- > 0; reversed ? i-- : i++) {
 		if (i == type)
 			continue;
-		if (v_ops->get_victim(sbi, &(curseg)->next_segno,
-						BG_GC, i, SSR))
+		if (v_ops->get_victim(sbi, &segno, BG_GC, i, SSR)) {
+			curseg->next_segno = segno;
 			return 1;
+		}
 	}
 	return 0;
 }