[PATCH v4 02/12] f2fs: cache: initialize meta cache

From: Chao Yu

Date: Thu Aug 27 2026 - 08:26:52 EST


From: Chao Yu <chao@xxxxxxxxxx>

This patch introduces meta_blocks in f2fs_sb_info structure, initializes
and destroys the meta cache during filesystem mount and unmount.

It also introduces helper wrappers for meta cache operation.

Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
fs/f2fs/cache.h | 12 ++++++++++++
fs/f2fs/data.c | 3 +++
fs/f2fs/f2fs.h | 3 +++
fs/f2fs/super.c | 10 +++++++++-
4 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/cache.h b/fs/f2fs/cache.h
index 0e201a36fcd5..cb5a466526fc 100644
--- a/fs/f2fs/cache.h
+++ b/fs/f2fs/cache.h
@@ -179,4 +179,16 @@ void f2fs_truncate_cache(struct f2fs_cached_block *entry, bool drop_dirty);
void f2fs_drop_cache_range(struct f2fs_cached_block_list *cache,
unsigned long start, unsigned long len, bool drop_dirty);

+int f2fs_start_cache_wb_thread(struct f2fs_sb_info *sbi);
+void f2fs_stop_cache_wb_thread(struct f2fs_sb_info *sbi);
+
+#define META_CACHE(sbi) (&(sbi)->meta_blocks)
+
+#define f2fs_find_meta_cache(sbi, blkaddr) \
+ f2fs_find_cache(META_CACHE(sbi), blkaddr)
+#define f2fs_invalidate_meta_caches(sbi, start, len) \
+ f2fs_drop_cache_range(META_CACHE(sbi), start, len, false)
+#define f2fs_truncate_meta_caches(sbi, start, len) \
+ f2fs_drop_cache_range(META_CACHE(sbi), start, len, true)
+
#endif /* _LINUX_F2FS_CACHE_H */
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 75ab768bb4f7..2c91382ffc3c 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -695,6 +695,9 @@ static bool __has_merged_page(struct bio *bio, struct inode *inode,
if (!inode && !folio && !ino)
return true;

+ if (f2fs_is_cache_bio(bio))
+ return false;
+
bio_for_each_folio_all(fi, bio) {
struct folio *target = fi.folio;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 84ee4601126d..0f855ac7d1e8 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2108,6 +2108,9 @@ struct f2fs_sb_info {
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lock_class_key cp_global_sem_key;
#endif
+
+ /* f2fs internal cache */
+ struct f2fs_cached_block_list meta_blocks;
};

/* Definitions to access f2fs_sb_info */
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index c1e315282ec6..32e80c70e141 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2075,6 +2075,8 @@ static void f2fs_put_super(struct super_block *sb)
iput(sbi->meta_inode);
sbi->meta_inode = NULL;

+ f2fs_destroy_cache(META_CACHE(sbi));
+
/* Should check the page counts after dropping all node/meta pages */
for (i = 0; i < NR_COUNT_TYPE; i++) {
if (!get_pages(sbi, i))
@@ -5225,12 +5227,16 @@ static int f2fs_fill_super(struct super_block *sb, struct fs_context *fc)
if (err)
goto free_percpu;

+ err = f2fs_init_cache(sbi, META_CACHE(sbi), F2FS_META_CACHE);
+ if (err)
+ goto free_page_array_cache;
+
/* get an inode for meta space */
sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
if (IS_ERR(sbi->meta_inode)) {
f2fs_err(sbi, "Failed to read F2FS meta data inode");
err = PTR_ERR(sbi->meta_inode);
- goto free_page_array_cache;
+ goto free_meta_cache;
}

err = f2fs_get_valid_checkpoint(sbi);
@@ -5564,6 +5570,8 @@ static int f2fs_fill_super(struct super_block *sb, struct fs_context *fc)
make_bad_inode(sbi->meta_inode);
iput(sbi->meta_inode);
sbi->meta_inode = NULL;
+free_meta_cache:
+ f2fs_destroy_cache(META_CACHE(sbi));
free_page_array_cache:
f2fs_destroy_page_array_cache(sbi);
free_percpu:
--
2.49.0