f2fs: support aligned pinned file

This patch supports 2MB-aligned pinned file, which can guarantee no GC at all
by allocating fully valid 2MB segment.

Check free segments by has_not_enough_free_secs() with large budget.

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

1 files changed, 27 insertions, 4 deletions

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 25c750cd0272..8bb37f8a1845 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2690,7 +2690,7 @@ unlock:
 	up_read(&SM_I(sbi)->curseg_lock);
 }
 
-void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi)
+void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi, int type)
 {
 	struct curseg_info *curseg;
 	unsigned int old_segno;
@@ -2699,10 +2699,17 @@ void f2fs_allocate_new_segments(struct f2fs_sb_info *sbi)
 	down_write(&SIT_I(sbi)->sentry_lock);
 
 	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
+		if (type != NO_CHECK_TYPE && i != type)
+			continue;
+
 		curseg = CURSEG_I(sbi, i);
-		old_segno = curseg->segno;
-		SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);
-		locate_dirty_segment(sbi, old_segno);
+		if (type == NO_CHECK_TYPE || curseg->next_blkoff ||
+				get_valid_blocks(sbi, curseg->segno, false) ||
+				get_ckpt_valid_blocks(sbi, curseg->segno)) {
+			old_segno = curseg->segno;
+			SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);
+			locate_dirty_segment(sbi, old_segno);
+		}
 	}
 
 	up_write(&SIT_I(sbi)->sentry_lock);
@@ -3068,6 +3075,19 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
 {
 	struct sit_info *sit_i = SIT_I(sbi);
 	struct curseg_info *curseg = CURSEG_I(sbi, type);
+	bool put_pin_sem = false;
+
+	if (type == CURSEG_COLD_DATA) {
+		/* GC during CURSEG_COLD_DATA_PINNED allocation */
+		if (down_read_trylock(&sbi->pin_sem)) {
+			put_pin_sem = true;
+		} else {
+			type = CURSEG_WARM_DATA;
+			curseg = CURSEG_I(sbi, type);
+		}
+	} else if (type == CURSEG_COLD_DATA_PINNED) {
+		type = CURSEG_COLD_DATA;
+	}
 
 	down_read(&SM_I(sbi)->curseg_lock);
 
@@ -3133,6 +3153,9 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
 	mutex_unlock(&curseg->curseg_mutex);
 
 	up_read(&SM_I(sbi)->curseg_lock);
+
+	if (put_pin_sem)
+		up_read(&sbi->pin_sem);
 }
 
 static void update_device_state(struct f2fs_io_info *fio)