f2fs: compress: add compress_inode to cache compressed blocks

Support to use address space of inner inode to cache compressed block,
in order to improve cache hit ratio of random read.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 68 insertions, 3 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index bbc36828a9d9..561e52a07391 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -98,6 +98,7 @@ extern const char *f2fs_fault_name[FAULT_MAX];
 #define F2FS_MOUNT_ATGC			0x08000000
 #define F2FS_MOUNT_MERGE_CHECKPOINT	0x10000000
 #define	F2FS_MOUNT_GC_MERGE		0x20000000
+#define F2FS_MOUNT_COMPRESS_CACHE	0x40000000
 
 #define F2FS_OPTION(sbi)	((sbi)->mount_opt)
 #define clear_opt(sbi, option)	(F2FS_OPTION(sbi).opt &= ~F2FS_MOUNT_##option)
@@ -1374,6 +1375,37 @@ PAGE_PRIVATE_CLEAR_FUNC(gcing, ONGOING_MIGRATION);
 PAGE_PRIVATE_CLEAR_FUNC(atomic, ATOMIC_WRITE);
 PAGE_PRIVATE_CLEAR_FUNC(dummy, DUMMY_WRITE);
 
+static inline unsigned long get_page_private_data(struct page *page)
+{
+	unsigned long data = page_private(page);
+
+	if (!test_bit(PAGE_PRIVATE_NOT_POINTER, &data))
+		return 0;
+	return data >> PAGE_PRIVATE_MAX;
+}
+
+static inline void set_page_private_data(struct page *page, unsigned long data)
+{
+	if (!PagePrivate(page)) {
+		get_page(page);
+		SetPagePrivate(page);
+	}
+	set_bit(PAGE_PRIVATE_NOT_POINTER, &page_private(page));
+	page_private(page) |= data << PAGE_PRIVATE_MAX;
+}
+
+static inline void clear_page_private_data(struct page *page)
+{
+	page_private(page) &= (1 << PAGE_PRIVATE_MAX) - 1;
+	if (page_private(page) == 1 << PAGE_PRIVATE_NOT_POINTER) {
+		set_page_private(page, 0);
+		if (PagePrivate(page)) {
+			ClearPagePrivate(page);
+			put_page(page);
+		}
+	}
+}
+
 /* For compression */
 enum compress_algorithm_type {
 	COMPRESS_LZO,
@@ -1388,6 +1420,9 @@ enum compress_flag {
 	COMPRESS_MAX_FLAG,
 };
 
+#define	COMPRESS_WATERMARK			20
+#define	COMPRESS_PERCENT			20
+
 #define COMPRESS_DATA_RESERVED_SIZE		4
 struct compress_data {
 	__le32 clen;			/* compressed data size */
@@ -1700,6 +1735,12 @@ struct f2fs_sb_info {
 	u64 compr_written_block;
 	u64 compr_saved_block;
 	u32 compr_new_inode;
+
+	/* For compressed block cache */
+	struct inode *compress_inode;		/* cache compressed blocks */
+	unsigned int compress_percent;		/* cache page percentage */
+	unsigned int compress_watermark;	/* cache page watermark */
+	atomic_t compress_page_hit;		/* cache hit count */
 #endif
 };
 
@@ -3671,7 +3712,8 @@ struct f2fs_stat_info {
 	unsigned int bimodal, avg_vblocks;
 	int util_free, util_valid, util_invalid;
 	int rsvd_segs, overp_segs;
-	int dirty_count, node_pages, meta_pages;
+	int dirty_count, node_pages, meta_pages, compress_pages;
+	int compress_page_hit;
 	int prefree_count, call_count, cp_count, bg_cp_count;
 	int tot_segs, node_segs, data_segs, free_segs, free_secs;
 	int bg_node_segs, bg_data_segs;
@@ -4007,7 +4049,9 @@ void f2fs_compress_write_end_io(struct bio *bio, struct page *page);
 bool f2fs_is_compress_backend_ready(struct inode *inode);
 int f2fs_init_compress_mempool(void);
 void f2fs_destroy_compress_mempool(void);
-void f2fs_end_read_compressed_page(struct page *page, bool failed);
+void f2fs_decompress_cluster(struct decompress_io_ctx *dic);
+void f2fs_end_read_compressed_page(struct page *page, bool failed,
+							block_t blkaddr);
 bool f2fs_cluster_is_empty(struct compress_ctx *cc);
 bool f2fs_cluster_can_merge_page(struct compress_ctx *cc, pgoff_t index);
 void f2fs_compress_ctx_add_page(struct compress_ctx *cc, struct page *page);
@@ -4025,10 +4069,19 @@ void f2fs_put_page_dic(struct page *page);
 int f2fs_init_compress_ctx(struct compress_ctx *cc);
 void f2fs_destroy_compress_ctx(struct compress_ctx *cc, bool reuse);
 void f2fs_init_compress_info(struct f2fs_sb_info *sbi);
+int f2fs_init_compress_inode(struct f2fs_sb_info *sbi);
+void f2fs_destroy_compress_inode(struct f2fs_sb_info *sbi);
 int f2fs_init_page_array_cache(struct f2fs_sb_info *sbi);
 void f2fs_destroy_page_array_cache(struct f2fs_sb_info *sbi);
 int __init f2fs_init_compress_cache(void);
 void f2fs_destroy_compress_cache(void);
+struct address_space *COMPRESS_MAPPING(struct f2fs_sb_info *sbi);
+void f2fs_invalidate_compress_page(struct f2fs_sb_info *sbi, block_t blkaddr);
+void f2fs_cache_compressed_page(struct f2fs_sb_info *sbi, struct page *page,
+						nid_t ino, block_t blkaddr);
+bool f2fs_load_compressed_page(struct f2fs_sb_info *sbi, struct page *page,
+								block_t blkaddr);
+void f2fs_invalidate_compress_pages(struct f2fs_sb_info *sbi, nid_t ino);
 #define inc_compr_inode_stat(inode)					\
 	do {								\
 		struct f2fs_sb_info *sbi = F2FS_I_SB(inode);		\
@@ -4057,7 +4110,9 @@ static inline struct page *f2fs_compress_control_page(struct page *page)
 }
 static inline int f2fs_init_compress_mempool(void) { return 0; }
 static inline void f2fs_destroy_compress_mempool(void) { }
-static inline void f2fs_end_read_compressed_page(struct page *page, bool failed)
+static inline void f2fs_decompress_cluster(struct decompress_io_ctx *dic) { }
+static inline void f2fs_end_read_compressed_page(struct page *page,
+						bool failed, block_t blkaddr)
 {
 	WARN_ON_ONCE(1);
 }
@@ -4065,10 +4120,20 @@ static inline void f2fs_put_page_dic(struct page *page)
 {
 	WARN_ON_ONCE(1);
 }
+static inline int f2fs_init_compress_inode(struct f2fs_sb_info *sbi) { return 0; }
+static inline void f2fs_destroy_compress_inode(struct f2fs_sb_info *sbi) { }
 static inline int f2fs_init_page_array_cache(struct f2fs_sb_info *sbi) { return 0; }
 static inline void f2fs_destroy_page_array_cache(struct f2fs_sb_info *sbi) { }
 static inline int __init f2fs_init_compress_cache(void) { return 0; }
 static inline void f2fs_destroy_compress_cache(void) { }
+static inline void f2fs_invalidate_compress_page(struct f2fs_sb_info *sbi,
+				block_t blkaddr) { }
+static inline void f2fs_cache_compressed_page(struct f2fs_sb_info *sbi,
+				struct page *page, nid_t ino, block_t blkaddr) { }
+static inline bool f2fs_load_compressed_page(struct f2fs_sb_info *sbi,
+				struct page *page, block_t blkaddr) { return false; }
+static inline void f2fs_invalidate_compress_pages(struct f2fs_sb_info *sbi,
+							nid_t ino) { }
 #define inc_compr_inode_stat(inode)		do { } while (0)
 #endif