f2fs: make max inline size changeable

This patch tries to make below macros calculating max inline size,
inline dentry field size considerring reserving size-changeable
space:
- MAX_INLINE_DATA
- NR_INLINE_DENTRY
- INLINE_DENTRY_BITMAP_SIZE
- INLINE_RESERVED_SIZE

Then, when inline_{data,dentry} options is enabled, it allows us to
reserve inline space with different size flexibly for adding newly
introduced inode attribute.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/data.c

@@ -813,7 +813,7 @@ int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
 				F2FS_GET_BLOCK_PRE_AIO :
 				F2FS_GET_BLOCK_PRE_DIO);
 	}
-	if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA) {
+	if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA(inode)) {
 		err = f2fs_convert_inline_inode(inode);
 		if (err)
 			return err;
@@ -1857,7 +1857,7 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
 	set_new_dnode(&dn, inode, ipage, ipage, 0);
 
 	if (f2fs_has_inline_data(inode)) {
-		if (pos + len <= MAX_INLINE_DATA) {
+		if (pos + len <= MAX_INLINE_DATA(inode)) {
 			read_inline_data(page, ipage);
 			set_inode_flag(inode, FI_DATA_EXIST);
 			if (inode->i_nlink)

fs/f2fs/f2fs.h

@@ -357,6 +357,25 @@ struct f2fs_flush_device {
 	u32 segments;		/* # of segments to flush */
 };
 
+/* for inline stuff */
+#define DEF_INLINE_RESERVED_SIZE	1
+
+static inline int get_inline_reserved_size(struct inode *inode);
+#define MAX_INLINE_DATA(inode)	(sizeof(__le32) * (DEF_ADDRS_PER_INODE -\
+				get_inline_reserved_size(inode) -\
+				F2FS_INLINE_XATTR_ADDRS))
+
+/* for inline dir */
+#define NR_INLINE_DENTRY(inode)	(MAX_INLINE_DATA(inode) * BITS_PER_BYTE / \
+				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
+				BITS_PER_BYTE + 1))
+#define INLINE_DENTRY_BITMAP_SIZE(inode)	((NR_INLINE_DENTRY(inode) + \
+					BITS_PER_BYTE - 1) / BITS_PER_BYTE)
+#define INLINE_RESERVED_SIZE(inode)	(MAX_INLINE_DATA(inode) - \
+				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
+				NR_INLINE_DENTRY(inode) + \
+				INLINE_DENTRY_BITMAP_SIZE(inode)))
+
 /*
  * For INODE and NODE manager
  */
@@ -382,14 +401,19 @@ static inline void make_dentry_ptr_block(struct inode *inode,
 }
 
 static inline void make_dentry_ptr_inline(struct inode *inode,
-		struct f2fs_dentry_ptr *d, struct f2fs_inline_dentry *t)
+					struct f2fs_dentry_ptr *d, void *t)
 {
+	int entry_cnt = NR_INLINE_DENTRY(inode);
+	int bitmap_size = INLINE_DENTRY_BITMAP_SIZE(inode);
+	int reserved_size = INLINE_RESERVED_SIZE(inode);
+
 	d->inode = inode;
-	d->max = NR_INLINE_DENTRY;
-	d->nr_bitmap = INLINE_DENTRY_BITMAP_SIZE;
-	d->bitmap = &t->dentry_bitmap;
-	d->dentry = t->dentry;
-	d->filename = t->filename;
+	d->max = entry_cnt;
+	d->nr_bitmap = bitmap_size;
+	d->bitmap = t;
+	d->dentry = t + bitmap_size + reserved_size;
+	d->filename = t + bitmap_size + reserved_size +
+					SIZE_OF_DIR_ENTRY * entry_cnt;
 }
 
 /*
@@ -543,6 +567,8 @@ struct f2fs_inode_info {
 	struct extent_tree *extent_tree;	/* cached extent_tree entry */
 	struct rw_semaphore dio_rwsem[2];/* avoid racing between dio and gc */
 	struct rw_semaphore i_mmap_sem;
+
+	int i_inline_reserved;		/* reserved size in inline data */
 };
 
 static inline void get_extent_info(struct extent_info *ext,
@@ -2075,11 +2101,12 @@ static inline bool f2fs_is_drop_cache(struct inode *inode)
 	return is_inode_flag_set(inode, FI_DROP_CACHE);
 }
 
-static inline void *inline_data_addr(struct page *page)
+static inline void *inline_data_addr(struct inode *inode, struct page *page)
 {
 	struct f2fs_inode *ri = F2FS_INODE(page);
+	int reserved_size = get_inline_reserved_size(inode);
 
-	return (void *)&(ri->i_addr[1]);
+	return (void *)&(ri->i_addr[reserved_size]);
 }
 
 static inline int f2fs_has_inline_dentry(struct inode *inode)
@@ -2170,6 +2197,11 @@ static inline void *f2fs_kmalloc(struct f2fs_sb_info *sbi,
 	return kmalloc(size, flags);
 }
 
+static inline int get_inline_reserved_size(struct inode *inode)
+{
+	return F2FS_I(inode)->i_inline_reserved;
+}
+
 #define get_inode_mode(i) \
 	((is_inode_flag_set(i, FI_ACL_MODE)) ? \
 	 (F2FS_I(i)->i_acl_mode) : ((i)->i_mode))

fs/f2fs/inode.c

@@ -87,9 +87,9 @@ static void __set_inode_rdev(struct inode *inode, struct f2fs_inode *ri)
 
 static void __recover_inline_status(struct inode *inode, struct page *ipage)
 {
-	void *inline_data = inline_data_addr(ipage);
+	void *inline_data = inline_data_addr(inode, ipage);
 	__le32 *start = inline_data;
-	__le32 *end = start + MAX_INLINE_DATA / sizeof(__le32);
+	__le32 *end = start + MAX_INLINE_DATA(inode) / sizeof(__le32);
 
 	while (start < end) {
 		if (*start++) {

fs/f2fs/super.c

@@ -446,6 +446,9 @@ static struct inode *f2fs_alloc_inode(struct super_block *sb)
 #endif
 	/* Will be used by directory only */
 	fi->i_dir_level = F2FS_SB(sb)->dir_level;
+
+	fi->i_inline_reserved = DEF_INLINE_RESERVED_SIZE;
+
 	return &fi->vfs_inode;
 }
 

include/linux/f2fs_fs.h

@@ -206,9 +206,6 @@ struct f2fs_extent {
 #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
 #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries */
 
-#define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
-						F2FS_INLINE_XATTR_ADDRS - 1))
-
 struct f2fs_inode {
 	__le16 i_mode;			/* file mode */
 	__u8 i_advise;			/* file hints */
@@ -465,7 +462,7 @@ typedef __le32	f2fs_hash_t;
 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
 
 /*
- * space utilization of regular dentry and inline dentry
+ * space utilization of regular dentry and inline dentry (w/o extra reservation)
  *		regular dentry			inline dentry
  * bitmap	1 * 27 = 27			1 * 23 = 23
  * reserved	1 * 3 = 3			1 * 7 = 7
@@ -501,24 +498,6 @@ struct f2fs_dentry_block {
 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
 } __packed;
 
-/* for inline dir */
-#define NR_INLINE_DENTRY	(MAX_INLINE_DATA * BITS_PER_BYTE / \
-				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
-				BITS_PER_BYTE + 1))
-#define INLINE_DENTRY_BITMAP_SIZE	((NR_INLINE_DENTRY + \
-					BITS_PER_BYTE - 1) / BITS_PER_BYTE)
-#define INLINE_RESERVED_SIZE	(MAX_INLINE_DATA - \
-				((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * \
-				NR_INLINE_DENTRY + INLINE_DENTRY_BITMAP_SIZE))
-
-/* inline directory entry structure */
-struct f2fs_inline_dentry {
-	__u8 dentry_bitmap[INLINE_DENTRY_BITMAP_SIZE];
-	__u8 reserved[INLINE_RESERVED_SIZE];
-	struct f2fs_dir_entry dentry[NR_INLINE_DENTRY];
-	__u8 filename[NR_INLINE_DENTRY][F2FS_SLOT_LEN];
-} __packed;
-
 /* file types used in inode_info->flags */
 enum {
 	F2FS_FT_UNKNOWN,