f2fs: introduce mode=lfs mount option
This mount option is to enable original log-structured filesystem forcefully.
So, there should be no random writes for main area.
Especially, this supports host-managed SMR device.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index eff046a..4792f94 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -707,6 +707,7 @@
struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
unsigned int start = 0, end = -1;
+ unsigned int secno, start_segno;
mutex_lock(&dirty_i->seglist_lock);
@@ -726,8 +727,22 @@
if (!test_opt(sbi, DISCARD))
continue;
- f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
+ if (!test_opt(sbi, LFS) || sbi->segs_per_sec == 1) {
+ f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
(end - start) << sbi->log_blocks_per_seg);
+ continue;
+ }
+next:
+ secno = GET_SECNO(sbi, start);
+ start_segno = secno * sbi->segs_per_sec;
+ if (!IS_CURSEC(sbi, secno) &&
+ !get_valid_blocks(sbi, start, sbi->segs_per_sec))
+ f2fs_issue_discard(sbi, START_BLOCK(sbi, start_segno),
+ sbi->segs_per_sec << sbi->log_blocks_per_seg);
+
+ start = start_segno + sbi->segs_per_sec;
+ if (start < end)
+ goto next;
}
mutex_unlock(&dirty_i->seglist_lock);
@@ -1221,6 +1236,9 @@
{
int i;
+ if (test_opt(sbi, LFS))
+ return;
+
for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++)
__allocate_new_segments(sbi, i);
}