[f2fs-dev,v2] f2fs-tools: disable nat_bits by default in Android

Commit Message

Chao Yu March 7, 2025, 1:59 a.m. UTC

This patch turns off nat_bits feature by default in Android,
for other scenario, keep it on and keep an eye on it.

Signed-off-by: Chao Yu <[e-mail]>
---
v2:
- fix to disable nat_bits feature in fsck tool.
 fsck/main.c             | 3 +++
 fsck/mount.c            | 3 ++-
 include/f2fs_fs.h       | 6 ++++++
 mkfs/f2fs_format.c      | 3 ++-
 mkfs/f2fs_format_main.c | 1 +
 5 files changed, 14 insertions(+), 2 deletions(-)

Patch

diff --git a/fsck/main.c b/fsck/main.c
index 25d50e2..9e0f94e 100644
--- a/fsck/main.c
+++ b/fsck/main.c
@@ -219,6 +219,9 @@  static void __add_fsck_options(void)
 {
 	/* -a */
 	c.auto_fix = 1;
+
+	/* disable nat_bits feature by default */
+	c.disabled_feature |= F2FS_FEATURE_NAT_BITS;
 }
 
 static void add_default_options(void)
diff --git a/fsck/mount.c b/fsck/mount.c
index e493f22..0b05f00 100644
--- a/fsck/mount.c
+++ b/fsck/mount.c
@@ -1713,7 +1713,8 @@  u32 update_nat_bits_flags(struct f2fs_super_block *sb,
 	nat_bits_bytes = get_sb(segment_count_nat) << 5;
 	nat_bits_blocks = F2FS_BYTES_TO_BLK((nat_bits_bytes << 1) + 8 +
 						F2FS_BLKSIZE - 1);
-	if (get_cp(cp_pack_total_block_count) <=
+	if (!(c.disabled_feature & F2FS_FEATURE_NAT_BITS) &&
+			get_cp(cp_pack_total_block_count) <=
 			(1 << get_sb(log_blocks_per_seg)) - nat_bits_blocks)
 		flags |= CP_NAT_BITS_FLAG;
 	else
diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
index 0cb9228..bb40adc 100644
--- a/include/f2fs_fs.h
+++ b/include/f2fs_fs.h
@@ -1471,6 +1471,11 @@  enum {
 
 #define MAX_CACHE_SUMS			8
 
+/* feature list in Android */
+enum {
+	F2FS_FEATURE_NAT_BITS = 0x0001,
+};
+
 struct f2fs_configuration {
 	uint32_t conf_reserved_sections;
 	uint32_t reserved_segments;
@@ -1537,6 +1542,7 @@  struct f2fs_configuration {
 	int large_nat_bitmap;
 	int fix_chksum;			/* fix old cp.chksum position */
 	unsigned int feature;			/* defined features */
+	unsigned int disabled_feature;	/* disabled feature, used for Android only */
 	unsigned int quota_bits;	/* quota bits */
 	time_t fixed_time;
 	int roll_forward;
diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
index 6635eed..c28ebb0 100644
--- a/mkfs/f2fs_format.c
+++ b/mkfs/f2fs_format.c
@@ -893,7 +893,8 @@  static int f2fs_write_check_point_pack(void)
 	/* cp page (2), data summaries (1), node summaries (3) */
 	set_cp(cp_pack_total_block_count, 6 + get_sb(cp_payload));
 	flags = CP_UMOUNT_FLAG | CP_COMPACT_SUM_FLAG;
-	if (get_cp(cp_pack_total_block_count) <=
+	if (!(c.disabled_feature & F2FS_FEATURE_NAT_BITS) &&
+			get_cp(cp_pack_total_block_count) <=
 			(1 << get_sb(log_blocks_per_seg)) - nat_bits_blocks)
 		flags |= CP_NAT_BITS_FLAG;
 
diff --git a/mkfs/f2fs_format_main.c b/mkfs/f2fs_format_main.c
index 9407f5b..5b4569d 100644
--- a/mkfs/f2fs_format_main.c
+++ b/mkfs/f2fs_format_main.c
@@ -143,6 +143,7 @@  static void add_default_options(void)
 		force_overwrite = 1;
 		c.wanted_sector_size = F2FS_BLKSIZE;
 		c.root_uid = c.root_gid = 0;
+		c.disabled_feature |= F2FS_FEATURE_NAT_BITS;
 
 		/* RO doesn't need any other features */
 		if (c.feature & F2FS_FEATURE_RO)