1 files changed, 199 insertions, 106 deletions

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index a946ce0ead34..4546e01b2ee0 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -7,7 +7,6 @@
  */
 #include <linux/fs.h>
 #include <linux/module.h>
-#include <linux/backing-dev.h>
 #include <linux/init.h>
 #include <linux/f2fs_fs.h>
 #include <linux/kthread.h>
@@ -15,6 +14,7 @@
 #include <linux/freezer.h>
 #include <linux/sched/signal.h>
 #include <linux/random.h>
+#include <linux/sched/mm.h>
 
 #include "f2fs.h"
 #include "node.h"
@@ -35,6 +35,10 @@ static int gc_thread_func(void *data)
 	wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head;
 	wait_queue_head_t *fggc_wq = &sbi->gc_thread->fggc_wq;
 	unsigned int wait_ms;
+	struct f2fs_gc_control gc_control = {
+		.victim_segno = NULL_SEGNO,
+		.should_migrate_blocks = false,
+		.err_gc_skipped = false };
 
 	wait_ms = gc_th->min_sleep_time;
 
@@ -70,7 +74,8 @@ static int gc_thread_func(void *data)
 
 		if (time_to_inject(sbi, FAULT_CHECKPOINT)) {
 			f2fs_show_injection_info(sbi, FAULT_CHECKPOINT);
-			f2fs_stop_checkpoint(sbi, false);
+			f2fs_stop_checkpoint(sbi, false,
+					STOP_CP_REASON_FAULT_INJECT);
 		}
 
 		if (!sb_start_write_trylock(sbi->sb)) {
@@ -92,22 +97,33 @@ static int gc_thread_func(void *data)
 		 * So, I'd like to wait some time to collect dirty segments.
 		 */
 		if (sbi->gc_mode == GC_URGENT_HIGH) {
+			spin_lock(&sbi->gc_urgent_high_lock);
+			if (sbi->gc_urgent_high_remaining) {
+				sbi->gc_urgent_high_remaining--;
+				if (!sbi->gc_urgent_high_remaining)
+					sbi->gc_mode = GC_NORMAL;
+			}
+			spin_unlock(&sbi->gc_urgent_high_lock);
+		}
+
+		if (sbi->gc_mode == GC_URGENT_HIGH ||
+				sbi->gc_mode == GC_URGENT_MID) {
 			wait_ms = gc_th->urgent_sleep_time;
-			down_write(&sbi->gc_lock);
+			f2fs_down_write(&sbi->gc_lock);
 			goto do_gc;
 		}
 
 		if (foreground) {
-			down_write(&sbi->gc_lock);
+			f2fs_down_write(&sbi->gc_lock);
 			goto do_gc;
-		} else if (!down_write_trylock(&sbi->gc_lock)) {
+		} else if (!f2fs_down_write_trylock(&sbi->gc_lock)) {
 			stat_other_skip_bggc_count(sbi);
 			goto next;
 		}
 
 		if (!is_idle(sbi, GC_TIME)) {
 			increase_sleep_time(gc_th, &wait_ms);
-			up_write(&sbi->gc_lock);
+			f2fs_up_write(&sbi->gc_lock);
 			stat_io_skip_bggc_count(sbi);
 			goto next;
 		}
@@ -126,9 +142,16 @@ do_gc:
 		if (foreground)
 			sync_mode = false;
 
+		gc_control.init_gc_type = sync_mode ? FG_GC : BG_GC;
+		gc_control.no_bg_gc = foreground;
+		gc_control.nr_free_secs = foreground ? 1 : 0;
+
 		/* if return value is not zero, no victim was selected */
-		if (f2fs_gc(sbi, sync_mode, !foreground, false, NULL_SEGNO))
-			wait_ms = gc_th->no_gc_sleep_time;
+		if (f2fs_gc(sbi, &gc_control)) {
+			/* don't bother wait_ms by foreground gc */
+			if (!foreground)
+				wait_ms = gc_th->no_gc_sleep_time;
+		}
 
 		if (foreground)
 			wake_up_all(&gc_th->fggc_wq);
@@ -259,7 +282,7 @@ static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
 
 	/* let's select beginning hot/small space first in no_heap mode*/
 	if (f2fs_need_rand_seg(sbi))
-		p->offset = prandom_u32() % (MAIN_SECS(sbi) * sbi->segs_per_sec);
+		p->offset = prandom_u32_max(MAIN_SECS(sbi) * sbi->segs_per_sec);
 	else if (test_opt(sbi, NOHEAP) &&
 		(type == CURSEG_HOT_DATA || IS_NODESEG(type)))
 		p->offset = 0;
@@ -464,7 +487,7 @@ static void atgc_lookup_victim(struct f2fs_sb_info *sbi,
 	unsigned long long age, u, accu;
 	unsigned long long max_mtime = sit_i->dirty_max_mtime;
 	unsigned long long min_mtime = sit_i->dirty_min_mtime;
-	unsigned int sec_blocks = BLKS_PER_SEC(sbi);
+	unsigned int sec_blocks = CAP_BLKS_PER_SEC(sbi);
 	unsigned int vblocks;
 	unsigned int dirty_threshold = max(am->max_candidate_count,
 					am->candidate_ratio *
@@ -631,6 +654,54 @@ static void release_victim_entry(struct f2fs_sb_info *sbi)
 	f2fs_bug_on(sbi, !list_empty(&am->victim_list));
 }
 
+static bool f2fs_pin_section(struct f2fs_sb_info *sbi, unsigned int segno)
+{
+	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
+	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
+
+	if (!dirty_i->enable_pin_section)
+		return false;
+	if (!test_and_set_bit(secno, dirty_i->pinned_secmap))
+		dirty_i->pinned_secmap_cnt++;
+	return true;
+}
+
+static bool f2fs_pinned_section_exists(struct dirty_seglist_info *dirty_i)
+{
+	return dirty_i->pinned_secmap_cnt;
+}
+
+static bool f2fs_section_is_pinned(struct dirty_seglist_info *dirty_i,
+						unsigned int secno)
+{
+	return dirty_i->enable_pin_section &&
+		f2fs_pinned_section_exists(dirty_i) &&
+		test_bit(secno, dirty_i->pinned_secmap);
+}
+
+static void f2fs_unpin_all_sections(struct f2fs_sb_info *sbi, bool enable)
+{
+	unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
+
+	if (f2fs_pinned_section_exists(DIRTY_I(sbi))) {
+		memset(DIRTY_I(sbi)->pinned_secmap, 0, bitmap_size);
+		DIRTY_I(sbi)->pinned_secmap_cnt = 0;
+	}
+	DIRTY_I(sbi)->enable_pin_section = enable;
+}
+
+static int f2fs_gc_pinned_control(struct inode *inode, int gc_type,
+							unsigned int segno)
+{
+	if (!f2fs_is_pinned_file(inode))
+		return 0;
+	if (gc_type != FG_GC)
+		return -EBUSY;
+	if (!f2fs_pin_section(F2FS_I_SB(inode), segno))
+		f2fs_pin_file_control(inode, true);
+	return -EAGAIN;
+}
+
 /*
  * This function is called from two paths.
  * One is garbage collection and the other is SSR segment selection.
@@ -772,6 +843,9 @@ retry:
 		if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
 			goto next;
 
+		if (gc_type == FG_GC && f2fs_section_is_pinned(dirty_i, secno))
+			goto next;
+
 		if (is_atgc) {
 			add_victim_entry(sbi, &p, segno);
 			goto next;
@@ -947,7 +1021,7 @@ next_step:
 			continue;
 		}
 
-		if (f2fs_get_node_info(sbi, nid, &ni)) {
+		if (f2fs_get_node_info(sbi, nid, &ni, false)) {
 			f2fs_put_page(node_page, 1);
 			continue;
 		}
@@ -1005,7 +1079,7 @@ static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
 {
 	struct page *node_page;
 	nid_t nid;
-	unsigned int ofs_in_node;
+	unsigned int ofs_in_node, max_addrs;
 	block_t source_blkaddr;
 
 	nid = le32_to_cpu(sum->nid);
@@ -1015,7 +1089,7 @@ static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
 	if (IS_ERR(node_page))
 		return false;
 
-	if (f2fs_get_node_info(sbi, nid, dni)) {
+	if (f2fs_get_node_info(sbi, nid, dni, false)) {
 		f2fs_put_page(node_page, 1);
 		return false;
 	}
@@ -1026,6 +1100,19 @@ static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
 		set_sbi_flag(sbi, SBI_NEED_FSCK);
 	}
 
+	if (f2fs_check_nid_range(sbi, dni->ino)) {
+		f2fs_put_page(node_page, 1);
+		return false;
+	}
+
+	max_addrs = IS_INODE(node_page) ? DEF_ADDRS_PER_INODE :
+						DEF_ADDRS_PER_BLOCK;
+	if (ofs_in_node >= max_addrs) {
+		f2fs_err(sbi, "Inconsistent ofs_in_node:%u in summary, ino:%u, nid:%u, max:%u",
+			ofs_in_node, dni->ino, dni->nid, max_addrs);
+		return false;
+	}
+
 	*nofs = ofs_of_node(node_page);
 	source_blkaddr = data_blkaddr(NULL, node_page, ofs_in_node);
 	f2fs_put_page(node_page, 1);
@@ -1039,7 +1126,7 @@ static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
 			if (!test_and_set_bit(segno, SIT_I(sbi)->invalid_segmap)) {
 				f2fs_err(sbi, "mismatched blkaddr %u (source_blkaddr %u) in seg %u",
 					 blkaddr, source_blkaddr, segno);
-				f2fs_bug_on(sbi, 1);
+				set_sbi_flag(sbi, SBI_NEED_FSCK);
 			}
 		}
 #endif
@@ -1077,6 +1164,7 @@ static int ra_data_block(struct inode *inode, pgoff_t index)
 		if (unlikely(!f2fs_is_valid_blkaddr(sbi, dn.data_blkaddr,
 						DATA_GENERIC_ENHANCE_READ))) {
 			err = -EFSCORRUPTED;
+			f2fs_handle_error(sbi, ERROR_INVALID_BLKADDR);
 			goto put_page;
 		}
 		goto got_it;
@@ -1095,6 +1183,7 @@ static int ra_data_block(struct inode *inode, pgoff_t index)
 	if (unlikely(!f2fs_is_valid_blkaddr(sbi, dn.data_blkaddr,
 						DATA_GENERIC_ENHANCE))) {
 		err = -EFSCORRUPTED;
+		f2fs_handle_error(sbi, ERROR_INVALID_BLKADDR);
 		goto put_page;
 	}
 got_it:
@@ -1124,8 +1213,8 @@ got_it:
 	f2fs_put_page(fio.encrypted_page, 0);
 	f2fs_put_page(page, 1);
 
-	f2fs_update_iostat(sbi, FS_DATA_READ_IO, F2FS_BLKSIZE);
-	f2fs_update_iostat(sbi, FS_GDATA_READ_IO, F2FS_BLKSIZE);
+	f2fs_update_iostat(sbi, inode, FS_DATA_READ_IO, F2FS_BLKSIZE);
+	f2fs_update_iostat(sbi, NULL, FS_GDATA_READ_IO, F2FS_BLKSIZE);
 
 	return 0;
 put_encrypted_page:
@@ -1174,18 +1263,9 @@ static int move_data_block(struct inode *inode, block_t bidx,
 		goto out;
 	}
 
-	if (f2fs_is_atomic_file(inode)) {
-		F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++;
-		F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++;
-		err = -EAGAIN;
-		goto out;
-	}
-
-	if (f2fs_is_pinned_file(inode)) {
-		f2fs_pin_file_control(inode, true);
-		err = -EAGAIN;
+	err = f2fs_gc_pinned_control(inode, gc_type, segno);
+	if (err)
 		goto out;
-	}
 
 	set_new_dnode(&dn, inode, NULL, NULL, 0);
 	err = f2fs_get_dnode_of_data(&dn, bidx, LOOKUP_NODE);
@@ -1206,7 +1286,7 @@ static int move_data_block(struct inode *inode, block_t bidx,
 
 	f2fs_wait_on_block_writeback(inode, dn.data_blkaddr);
 
-	err = f2fs_get_node_info(fio.sbi, dn.nid, &ni);
+	err = f2fs_get_node_info(fio.sbi, dn.nid, &ni, false);
 	if (err)
 		goto put_out;
 
@@ -1215,7 +1295,7 @@ static int move_data_block(struct inode *inode, block_t bidx,
 	fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr;
 
 	if (lfs_mode)
-		down_write(&fio.sbi->io_order_lock);
+		f2fs_down_write(&fio.sbi->io_order_lock);
 
 	mpage = f2fs_grab_cache_page(META_MAPPING(fio.sbi),
 					fio.old_blkaddr, false);
@@ -1234,8 +1314,10 @@ static int move_data_block(struct inode *inode, block_t bidx,
 			goto up_out;
 		}
 
-		f2fs_update_iostat(fio.sbi, FS_DATA_READ_IO, F2FS_BLKSIZE);
-		f2fs_update_iostat(fio.sbi, FS_GDATA_READ_IO, F2FS_BLKSIZE);
+		f2fs_update_iostat(fio.sbi, inode, FS_DATA_READ_IO,
+							F2FS_BLKSIZE);
+		f2fs_update_iostat(fio.sbi, NULL, FS_GDATA_READ_IO,
+							F2FS_BLKSIZE);
 
 		lock_page(mpage);
 		if (unlikely(mpage->mapping != META_MAPPING(fio.sbi) ||
@@ -1287,7 +1369,7 @@ static int move_data_block(struct inode *inode, block_t bidx,
 		goto put_page_out;
 	}
 
-	f2fs_update_iostat(fio.sbi, FS_GC_DATA_IO, F2FS_BLKSIZE);
+	f2fs_update_iostat(fio.sbi, NULL, FS_GC_DATA_IO, F2FS_BLKSIZE);
 
 	f2fs_update_data_blkaddr(&dn, newaddr);
 	set_inode_flag(inode, FI_APPEND_WRITE);
@@ -1301,7 +1383,7 @@ recover_block:
 							true, true, true);
 up_out:
 	if (lfs_mode)
-		up_write(&fio.sbi->io_order_lock);
+		f2fs_up_write(&fio.sbi->io_order_lock);
 put_out:
 	f2fs_put_dnode(&dn);
 out:
@@ -1324,18 +1406,9 @@ static int move_data_page(struct inode *inode, block_t bidx, int gc_type,
 		goto out;
 	}
 
-	if (f2fs_is_atomic_file(inode)) {
-		F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++;
-		F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++;
-		err = -EAGAIN;
-		goto out;
-	}
-	if (f2fs_is_pinned_file(inode)) {
-		if (gc_type == FG_GC)
-			f2fs_pin_file_control(inode, true);
-		err = -EAGAIN;
+	err = f2fs_gc_pinned_control(inode, gc_type, segno);
+	if (err)
 		goto out;
-	}
 
 	if (gc_type == BG_GC) {
 		if (PageWriteback(page)) {
@@ -1375,8 +1448,7 @@ retry:
 		if (err) {
 			clear_page_private_gcing(page);
 			if (err == -ENOMEM) {
-				congestion_wait(BLK_RW_ASYNC,
-						DEFAULT_IO_TIMEOUT);
+				memalloc_retry_wait(GFP_NOFS);
 				goto retry;
 			}
 			if (is_dirty)
@@ -1427,7 +1499,7 @@ next_step:
 		 */
 		if ((gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0)) ||
 			(!force_migrate && get_valid_blocks(sbi, segno, true) ==
-							BLKS_PER_SEC(sbi)))
+							CAP_BLKS_PER_SEC(sbi)))
 			return submitted;
 
 		if (check_valid_map(sbi, segno, off) == 0)
@@ -1456,11 +1528,20 @@ next_step:
 		ofs_in_node = le16_to_cpu(entry->ofs_in_node);
 
 		if (phase == 3) {
+			int err;
+
 			inode = f2fs_iget(sb, dni.ino);
-			if (IS_ERR(inode) || is_bad_inode(inode))
+			if (IS_ERR(inode) || is_bad_inode(inode) ||
+					special_file(inode->i_mode))
 				continue;
 
-			if (!down_write_trylock(
+			err = f2fs_gc_pinned_control(inode, gc_type, segno);
+			if (err == -EAGAIN) {
+				iput(inode);
+				return submitted;
+			}
+
+			if (!f2fs_down_write_trylock(
 				&F2FS_I(inode)->i_gc_rwsem[WRITE])) {
 				iput(inode);
 				sbi->skipped_gc_rwsem++;
@@ -1473,7 +1554,7 @@ next_step:
 			if (f2fs_post_read_required(inode)) {
 				int err = ra_data_block(inode, start_bidx);
 
-				up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+				f2fs_up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
 				if (err) {
 					iput(inode);
 					continue;
@@ -1484,7 +1565,7 @@ next_step:
 
 			data_page = f2fs_get_read_data_page(inode,
 						start_bidx, REQ_RAHEAD, true);
-			up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+			f2fs_up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
 			if (IS_ERR(data_page)) {
 				iput(inode);
 				continue;
@@ -1503,14 +1584,14 @@ next_step:
 			int err;
 
 			if (S_ISREG(inode->i_mode)) {
-				if (!down_write_trylock(&fi->i_gc_rwsem[READ])) {
+				if (!f2fs_down_write_trylock(&fi->i_gc_rwsem[READ])) {
 					sbi->skipped_gc_rwsem++;
 					continue;
 				}
-				if (!down_write_trylock(
+				if (!f2fs_down_write_trylock(
 						&fi->i_gc_rwsem[WRITE])) {
 					sbi->skipped_gc_rwsem++;
-					up_write(&fi->i_gc_rwsem[READ]);
+					f2fs_up_write(&fi->i_gc_rwsem[READ]);
 					continue;
 				}
 				locked = true;
@@ -1533,8 +1614,8 @@ next_step:
 				submitted++;
 
 			if (locked) {
-				up_write(&fi->i_gc_rwsem[WRITE]);
-				up_write(&fi->i_gc_rwsem[READ]);
+				f2fs_up_write(&fi->i_gc_rwsem[WRITE]);
+				f2fs_up_write(&fi->i_gc_rwsem[READ]);
 			}
 
 			stat_inc_data_blk_count(sbi, 1, gc_type);
@@ -1634,7 +1715,8 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi,
 			f2fs_err(sbi, "Inconsistent segment (%u) type [%d, %d] in SSA and SIT",
 				 segno, type, GET_SUM_TYPE((&sum->footer)));
 			set_sbi_flag(sbi, SBI_NEED_FSCK);
-			f2fs_stop_checkpoint(sbi, false);
+			f2fs_stop_checkpoint(sbi, false,
+				STOP_CP_REASON_CORRUPTED_SUMMARY);
 			goto skip;
 		}
 
@@ -1679,23 +1761,21 @@ skip:
 	return seg_freed;
 }
 
-int f2fs_gc(struct f2fs_sb_info *sbi, bool sync,
-			bool background, bool force, unsigned int segno)
+int f2fs_gc(struct f2fs_sb_info *sbi, struct f2fs_gc_control *gc_control)
 {
-	int gc_type = sync ? FG_GC : BG_GC;
+	int gc_type = gc_control->init_gc_type;
+	unsigned int segno = gc_control->victim_segno;
 	int sec_freed = 0, seg_freed = 0, total_freed = 0;
 	int ret = 0;
 	struct cp_control cpc;
-	unsigned int init_segno = segno;
 	struct gc_inode_list gc_list = {
 		.ilist = LIST_HEAD_INIT(gc_list.ilist),
 		.iroot = RADIX_TREE_INIT(gc_list.iroot, GFP_NOFS),
 	};
-	unsigned long long last_skipped = sbi->skipped_atomic_files[FG_GC];
-	unsigned long long first_skipped;
 	unsigned int skipped_round = 0, round = 0;
 
-	trace_f2fs_gc_begin(sbi->sb, sync, background,
+	trace_f2fs_gc_begin(sbi->sb, gc_type, gc_control->no_bg_gc,
+				gc_control->nr_free_secs,
 				get_pages(sbi, F2FS_DIRTY_NODES),
 				get_pages(sbi, F2FS_DIRTY_DENTS),
 				get_pages(sbi, F2FS_DIRTY_IMETA),
@@ -1706,7 +1786,6 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync,
 
 	cpc.reason = __get_cp_reason(sbi);
 	sbi->skipped_gc_rwsem = 0;
-	first_skipped = last_skipped;
 gc_more:
 	if (unlikely(!(sbi->sb->s_flags & SB_ACTIVE))) {
 		ret = -EINVAL;
@@ -1723,8 +1802,7 @@ gc_more:
 		 * threshold, we can make them free by checkpoint. Then, we
 		 * secure free segments which doesn't need fggc any more.
 		 */
-		if (prefree_segments(sbi) &&
-				!is_sbi_flag_set(sbi, SBI_CP_DISABLED)) {
+		if (prefree_segments(sbi)) {
 			ret = f2fs_write_checkpoint(sbi, &cpc);
 			if (ret)
 				goto stop;
@@ -1734,54 +1812,69 @@ gc_more:
 	}
 
 	/* f2fs_balance_fs doesn't need to do BG_GC in critical path. */
-	if (gc_type == BG_GC && !background) {
+	if (gc_type == BG_GC && gc_control->no_bg_gc) {
 		ret = -EINVAL;
 		goto stop;
 	}
+retry:
 	ret = __get_victim(sbi, &segno, gc_type);
-	if (ret)
+	if (ret) {
+		/* allow to search victim from sections has pinned data */
+		if (ret == -ENODATA && gc_type == FG_GC &&
+				f2fs_pinned_section_exists(DIRTY_I(sbi))) {
+			f2fs_unpin_all_sections(sbi, false);
+			goto retry;
+		}
 		goto stop;
+	}
 
-	seg_freed = do_garbage_collect(sbi, segno, &gc_list, gc_type, force);
-	if (gc_type == FG_GC &&
-		seg_freed == f2fs_usable_segs_in_sec(sbi, segno))
-		sec_freed++;
+	seg_freed = do_garbage_collect(sbi, segno, &gc_list, gc_type,
+				gc_control->should_migrate_blocks);
 	total_freed += seg_freed;
 
-	if (gc_type == FG_GC) {
-		if (sbi->skipped_atomic_files[FG_GC] > last_skipped ||
-						sbi->skipped_gc_rwsem)
-			skipped_round++;
-		last_skipped = sbi->skipped_atomic_files[FG_GC];
-		round++;
-	}
+	if (seg_freed == f2fs_usable_segs_in_sec(sbi, segno))
+		sec_freed++;
 
 	if (gc_type == FG_GC)
 		sbi->cur_victim_sec = NULL_SEGNO;
 
-	if (sync)
+	if (gc_control->init_gc_type == FG_GC ||
+	    !has_not_enough_free_secs(sbi,
+				(gc_type == FG_GC) ? sec_freed : 0, 0)) {
+		if (gc_type == FG_GC && sec_freed < gc_control->nr_free_secs)
+			goto go_gc_more;
 		goto stop;
+	}
 
-	if (has_not_enough_free_secs(sbi, sec_freed, 0)) {
-		if (skipped_round <= MAX_SKIP_GC_COUNT ||
-					skipped_round * 2 < round) {
-			segno = NULL_SEGNO;
-			goto gc_more;
+	/* FG_GC stops GC by skip_count */
+	if (gc_type == FG_GC) {
+		if (sbi->skipped_gc_rwsem)
+			skipped_round++;
+		round++;
+		if (skipped_round > MAX_SKIP_GC_COUNT &&
+				skipped_round * 2 >= round) {
+			ret = f2fs_write_checkpoint(sbi, &cpc);
+			goto stop;
 		}
+	}
 
-		if (first_skipped < last_skipped &&
-				(last_skipped - first_skipped) >
-						sbi->skipped_gc_rwsem) {
-			f2fs_drop_inmem_pages_all(sbi, true);
-			segno = NULL_SEGNO;
-			goto gc_more;
-		}
-		if (gc_type == FG_GC && !is_sbi_flag_set(sbi, SBI_CP_DISABLED))
-			ret = f2fs_write_checkpoint(sbi, &cpc);
+	/* Write checkpoint to reclaim prefree segments */
+	if (free_sections(sbi) < NR_CURSEG_PERSIST_TYPE &&
+				prefree_segments(sbi)) {
+		ret = f2fs_write_checkpoint(sbi, &cpc);
+		if (ret)
+			goto stop;
 	}
+go_gc_more:
+	segno = NULL_SEGNO;
+	goto gc_more;
+
 stop:
 	SIT_I(sbi)->last_victim[ALLOC_NEXT] = 0;
-	SIT_I(sbi)->last_victim[FLUSH_DEVICE] = init_segno;
+	SIT_I(sbi)->last_victim[FLUSH_DEVICE] = gc_control->victim_segno;
+
+	if (gc_type == FG_GC)
+		f2fs_unpin_all_sections(sbi, true);
 
 	trace_f2fs_gc_end(sbi->sb, ret, total_freed, sec_freed,
 				get_pages(sbi, F2FS_DIRTY_NODES),
@@ -1792,11 +1885,11 @@ stop:
 				reserved_segments(sbi),
 				prefree_segments(sbi));
 
-	up_write(&sbi->gc_lock);
+	f2fs_up_write(&sbi->gc_lock);
 
 	put_gc_inode(&gc_list);
 
-	if (sync && !ret)
+	if (gc_control->err_gc_skipped && !ret)
 		ret = sec_freed ? 0 : -EAGAIN;
 	return ret;
 }
@@ -1921,7 +2014,7 @@ static void update_sb_metadata(struct f2fs_sb_info *sbi, int secs)
 	long long block_count;
 	int segs = secs * sbi->segs_per_sec;
 
-	down_write(&sbi->sb_lock);
+	f2fs_down_write(&sbi->sb_lock);
 
 	section_count = le32_to_cpu(raw_sb->section_count);
 	segment_count = le32_to_cpu(raw_sb->segment_count);
@@ -1942,7 +2035,7 @@ static void update_sb_metadata(struct f2fs_sb_info *sbi, int secs)
 						cpu_to_le32(dev_segs + segs);
 	}
 
-	up_write(&sbi->sb_lock);
+	f2fs_up_write(&sbi->sb_lock);
 }
 
 static void update_fs_metadata(struct f2fs_sb_info *sbi, int secs)
@@ -2016,7 +2109,7 @@ int f2fs_resize_fs(struct f2fs_sb_info *sbi, __u64 block_count)
 	secs = div_u64(shrunk_blocks, BLKS_PER_SEC(sbi));
 
 	/* stop other GC */
-	if (!down_write_trylock(&sbi->gc_lock))
+	if (!f2fs_down_write_trylock(&sbi->gc_lock))
 		return -EAGAIN;
 
 	/* stop CP to protect MAIN_SEC in free_segment_range */
@@ -2036,15 +2129,15 @@ int f2fs_resize_fs(struct f2fs_sb_info *sbi, __u64 block_count)
 
 out_unlock:
 	f2fs_unlock_op(sbi);
-	up_write(&sbi->gc_lock);
+	f2fs_up_write(&sbi->gc_lock);
 	if (err)
 		return err;
 
 	set_sbi_flag(sbi, SBI_IS_RESIZEFS);
 
 	freeze_super(sbi->sb);
-	down_write(&sbi->gc_lock);
-	down_write(&sbi->cp_global_sem);
+	f2fs_down_write(&sbi->gc_lock);
+	f2fs_down_write(&sbi->cp_global_sem);
 
 	spin_lock(&sbi->stat_lock);
 	if (shrunk_blocks + valid_user_blocks(sbi) +
@@ -2089,8 +2182,8 @@ recover_out:
 		spin_unlock(&sbi->stat_lock);
 	}
 out_err:
-	up_write(&sbi->cp_global_sem);
-	up_write(&sbi->gc_lock);
+	f2fs_up_write(&sbi->cp_global_sem);
+	f2fs_up_write(&sbi->gc_lock);
 	thaw_super(sbi->sb);
 	clear_sbi_flag(sbi, SBI_IS_RESIZEFS);
 	return err;