[PATCH] Revert "f2fs: rebuild nat_bits during umount"

From: Chao Yu
Date: Wed Mar 05 2025 - 06:07:30 EST


It reports that there is potential corruption in node footer,
the most suspious feature is nat_bits, let's revert recovery
related code.

Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
fs/f2fs/checkpoint.c | 21 +++------
fs/f2fs/f2fs.h | 32 +++++++++++++-
fs/f2fs/node.c | 101 ++++++++++---------------------------------
3 files changed, 59 insertions(+), 95 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index bc9369ea6607..1bc5c2006c56 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1348,21 +1348,13 @@ static void update_ckpt_flags(struct f2fs_sb_info *sbi, struct cp_control *cpc)
struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
unsigned long flags;

- if (cpc->reason & CP_UMOUNT) {
- if (le32_to_cpu(ckpt->cp_pack_total_block_count) +
- NM_I(sbi)->nat_bits_blocks > BLKS_PER_SEG(sbi)) {
- clear_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
- f2fs_notice(sbi, "Disable nat_bits due to no space");
- } else if (!is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG) &&
- f2fs_nat_bitmap_enabled(sbi)) {
- f2fs_enable_nat_bits(sbi);
- set_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
- f2fs_notice(sbi, "Rebuild and enable nat_bits");
- }
- }
-
spin_lock_irqsave(&sbi->cp_lock, flags);

+ if ((cpc->reason & CP_UMOUNT) &&
+ le32_to_cpu(ckpt->cp_pack_total_block_count) >
+ sbi->blocks_per_seg - NM_I(sbi)->nat_bits_blocks)
+ disable_nat_bits(sbi, false);
+
if (cpc->reason & CP_TRIMMED)
__set_ckpt_flags(ckpt, CP_TRIMMED_FLAG);
else
@@ -1545,8 +1537,7 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
start_blk = __start_cp_next_addr(sbi);

/* write nat bits */
- if ((cpc->reason & CP_UMOUNT) &&
- is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG)) {
+ if (enabled_nat_bits(sbi, cpc)) {
__u64 cp_ver = cur_cp_version(ckpt);
block_t blk;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 6b4579b05dbf..8d8917b92b5d 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2231,6 +2231,36 @@ static inline void f2fs_up_write(struct f2fs_rwsem *sem)
#endif
}

+static inline void disable_nat_bits(struct f2fs_sb_info *sbi, bool lock)
+{
+ unsigned long flags;
+ unsigned char *nat_bits;
+
+ /*
+ * In order to re-enable nat_bits we need to call fsck.f2fs by
+ * set_sbi_flag(sbi, SBI_NEED_FSCK). But it may give huge cost,
+ * so let's rely on regular fsck or unclean shutdown.
+ */
+
+ if (lock)
+ spin_lock_irqsave(&sbi->cp_lock, flags);
+ __clear_ckpt_flags(F2FS_CKPT(sbi), CP_NAT_BITS_FLAG);
+ nat_bits = NM_I(sbi)->nat_bits;
+ NM_I(sbi)->nat_bits = NULL;
+ if (lock)
+ spin_unlock_irqrestore(&sbi->cp_lock, flags);
+
+ kvfree(nat_bits);
+}
+
+static inline bool enabled_nat_bits(struct f2fs_sb_info *sbi,
+ struct cp_control *cpc)
+{
+ bool set = is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
+
+ return (cpc) ? (cpc->reason & CP_UMOUNT) && set : set;
+}
+
static inline void f2fs_lock_op(struct f2fs_sb_info *sbi)
{
f2fs_down_read(&sbi->cp_rwsem);
@@ -3695,7 +3725,6 @@ int f2fs_truncate_inode_blocks(struct inode *inode, pgoff_t from);
int f2fs_truncate_xattr_node(struct inode *inode);
int f2fs_wait_on_node_pages_writeback(struct f2fs_sb_info *sbi,
unsigned int seq_id);
-bool f2fs_nat_bitmap_enabled(struct f2fs_sb_info *sbi);
int f2fs_remove_inode_page(struct inode *inode);
struct page *f2fs_new_inode_page(struct inode *inode);
struct page *f2fs_new_node_page(struct dnode_of_data *dn, unsigned int ofs);
@@ -3723,7 +3752,6 @@ int f2fs_recover_xattr_data(struct inode *inode, struct page *page);
int f2fs_recover_inode_page(struct f2fs_sb_info *sbi, struct page *page);
int f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
unsigned int segno, struct f2fs_summary_block *sum);
-void f2fs_enable_nat_bits(struct f2fs_sb_info *sbi);
int f2fs_flush_nat_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc);
int f2fs_build_node_manager(struct f2fs_sb_info *sbi);
void f2fs_destroy_node_manager(struct f2fs_sb_info *sbi);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 5f512dd5fadf..8c35fd4fa200 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -2311,24 +2311,6 @@ static void __move_free_nid(struct f2fs_sb_info *sbi, struct free_nid *i,
}
}

-bool f2fs_nat_bitmap_enabled(struct f2fs_sb_info *sbi)
-{
- struct f2fs_nm_info *nm_i = NM_I(sbi);
- unsigned int i;
- bool ret = true;
-
- f2fs_down_read(&nm_i->nat_tree_lock);
- for (i = 0; i < nm_i->nat_blocks; i++) {
- if (!test_bit_le(i, nm_i->nat_block_bitmap)) {
- ret = false;
- break;
- }
- }
- f2fs_up_read(&nm_i->nat_tree_lock);
-
- return ret;
-}
-
static void update_free_nid_bitmap(struct f2fs_sb_info *sbi, nid_t nid,
bool set, bool build)
{
@@ -3010,23 +2992,7 @@ static void __adjust_nat_entry_set(struct nat_entry_set *nes,
list_add_tail(&nes->set_list, head);
}

-static void __update_nat_bits(struct f2fs_nm_info *nm_i, unsigned int nat_ofs,
- unsigned int valid)
-{
- if (valid == 0) {
- __set_bit_le(nat_ofs, nm_i->empty_nat_bits);
- __clear_bit_le(nat_ofs, nm_i->full_nat_bits);
- return;
- }
-
- __clear_bit_le(nat_ofs, nm_i->empty_nat_bits);
- if (valid == NAT_ENTRY_PER_BLOCK)
- __set_bit_le(nat_ofs, nm_i->full_nat_bits);
- else
- __clear_bit_le(nat_ofs, nm_i->full_nat_bits);
-}
-
-static void update_nat_bits(struct f2fs_sb_info *sbi, nid_t start_nid,
+static void __update_nat_bits(struct f2fs_sb_info *sbi, nid_t start_nid,
struct page *page)
{
struct f2fs_nm_info *nm_i = NM_I(sbi);
@@ -3035,7 +3001,7 @@ static void update_nat_bits(struct f2fs_sb_info *sbi, nid_t start_nid,
int valid = 0;
int i = 0;

- if (!is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG))
+ if (!enabled_nat_bits(sbi, NULL))
return;

if (nat_index == 0) {
@@ -3046,36 +3012,17 @@ static void update_nat_bits(struct f2fs_sb_info *sbi, nid_t start_nid,
if (le32_to_cpu(nat_blk->entries[i].block_addr) != NULL_ADDR)
valid++;
}
-
- __update_nat_bits(nm_i, nat_index, valid);
-}
-
-void f2fs_enable_nat_bits(struct f2fs_sb_info *sbi)
-{
- struct f2fs_nm_info *nm_i = NM_I(sbi);
- unsigned int nat_ofs;
-
- f2fs_down_read(&nm_i->nat_tree_lock);
-
- for (nat_ofs = 0; nat_ofs < nm_i->nat_blocks; nat_ofs++) {
- unsigned int valid = 0, nid_ofs = 0;
-
- /* handle nid zero due to it should never be used */
- if (unlikely(nat_ofs == 0)) {
- valid = 1;
- nid_ofs = 1;
- }
-
- for (; nid_ofs < NAT_ENTRY_PER_BLOCK; nid_ofs++) {
- if (!test_bit_le(nid_ofs,
- nm_i->free_nid_bitmap[nat_ofs]))
- valid++;
- }
-
- __update_nat_bits(nm_i, nat_ofs, valid);
+ if (valid == 0) {
+ __set_bit_le(nat_index, nm_i->empty_nat_bits);
+ __clear_bit_le(nat_index, nm_i->full_nat_bits);
+ return;
}

- f2fs_up_read(&nm_i->nat_tree_lock);
+ __clear_bit_le(nat_index, nm_i->empty_nat_bits);
+ if (valid == NAT_ENTRY_PER_BLOCK)
+ __set_bit_le(nat_index, nm_i->full_nat_bits);
+ else
+ __clear_bit_le(nat_index, nm_i->full_nat_bits);
}

static int __flush_nat_entry_set(struct f2fs_sb_info *sbi,
@@ -3094,7 +3041,7 @@ static int __flush_nat_entry_set(struct f2fs_sb_info *sbi,
* #1, flush nat entries to journal in current hot data summary block.
* #2, flush nat entries to nat page.
*/
- if ((cpc->reason & CP_UMOUNT) ||
+ if (enabled_nat_bits(sbi, cpc) ||
!__has_cursum_space(journal, set->entry_cnt, NAT_JOURNAL))
to_journal = false;

@@ -3141,7 +3088,7 @@ static int __flush_nat_entry_set(struct f2fs_sb_info *sbi,
if (to_journal) {
up_write(&curseg->journal_rwsem);
} else {
- update_nat_bits(sbi, start_nid, page);
+ __update_nat_bits(sbi, start_nid, page);
f2fs_put_page(page, 1);
}

@@ -3172,7 +3119,7 @@ int f2fs_flush_nat_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
* during unmount, let's flush nat_bits before checking
* nat_cnt[DIRTY_NAT].
*/
- if (cpc->reason & CP_UMOUNT) {
+ if (enabled_nat_bits(sbi, cpc)) {
f2fs_down_write(&nm_i->nat_tree_lock);
remove_nats_in_journal(sbi);
f2fs_up_write(&nm_i->nat_tree_lock);
@@ -3188,7 +3135,7 @@ int f2fs_flush_nat_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
* entries, remove all entries from journal and merge them
* into nat entry set.
*/
- if (cpc->reason & CP_UMOUNT ||
+ if (enabled_nat_bits(sbi, cpc) ||
!__has_cursum_space(journal,
nm_i->nat_cnt[DIRTY_NAT], NAT_JOURNAL))
remove_nats_in_journal(sbi);
@@ -3225,18 +3172,15 @@ static int __get_nat_bitmaps(struct f2fs_sb_info *sbi)
__u64 cp_ver = cur_cp_version(ckpt);
block_t nat_bits_addr;

+ if (!enabled_nat_bits(sbi, NULL))
+ return 0;
+
nm_i->nat_bits_blocks = F2FS_BLK_ALIGN((nat_bits_bytes << 1) + 8);
nm_i->nat_bits = f2fs_kvzalloc(sbi,
F2FS_BLK_TO_BYTES(nm_i->nat_bits_blocks), GFP_KERNEL);
if (!nm_i->nat_bits)
return -ENOMEM;

- nm_i->full_nat_bits = nm_i->nat_bits + 8;
- nm_i->empty_nat_bits = nm_i->full_nat_bits + nat_bits_bytes;
-
- if (!is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG))
- return 0;
-
nat_bits_addr = __start_cp_addr(sbi) + BLKS_PER_SEG(sbi) -
nm_i->nat_bits_blocks;
for (i = 0; i < nm_i->nat_bits_blocks; i++) {
@@ -3253,12 +3197,13 @@ static int __get_nat_bitmaps(struct f2fs_sb_info *sbi)

cp_ver |= (cur_cp_crc(ckpt) << 32);
if (cpu_to_le64(cp_ver) != *(__le64 *)nm_i->nat_bits) {
- clear_ckpt_flags(sbi, CP_NAT_BITS_FLAG);
- f2fs_notice(sbi, "Disable nat_bits due to incorrect cp_ver (%llu, %llu)",
- cp_ver, le64_to_cpu(*(__le64 *)nm_i->nat_bits));
+ disable_nat_bits(sbi, true);
return 0;
}

+ nm_i->full_nat_bits = nm_i->nat_bits + 8;
+ nm_i->empty_nat_bits = nm_i->full_nat_bits + nat_bits_bytes;
+
f2fs_notice(sbi, "Found nat_bits in checkpoint");
return 0;
}
@@ -3269,7 +3214,7 @@ static inline void load_free_nid_bitmap(struct f2fs_sb_info *sbi)
unsigned int i = 0;
nid_t nid, last_nid;

- if (!is_set_ckpt_flags(sbi, CP_NAT_BITS_FLAG))
+ if (!enabled_nat_bits(sbi, NULL))
return;

for (i = 0; i < nm_i->nat_blocks; i++) {
--
2.48.1