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, 34 insertions, 1 deletions

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 3e0e34b4680c..d70122da3f99 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -150,6 +150,7 @@ enum {
 	Opt_compress_extension,
 	Opt_compress_chksum,
 	Opt_compress_mode,
+	Opt_compress_cache,
 	Opt_atgc,
 	Opt_gc_merge,
 	Opt_nogc_merge,
@@ -224,6 +225,7 @@ static match_table_t f2fs_tokens = {
 	{Opt_compress_extension, "compress_extension=%s"},
 	{Opt_compress_chksum, "compress_chksum"},
 	{Opt_compress_mode, "compress_mode=%s"},
+	{Opt_compress_cache, "compress_cache"},
 	{Opt_atgc, "atgc"},
 	{Opt_gc_merge, "gc_merge"},
 	{Opt_nogc_merge, "nogc_merge"},
@@ -1066,12 +1068,16 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount)
 			}
 			kfree(name);
 			break;
+		case Opt_compress_cache:
+			set_opt(sbi, COMPRESS_CACHE);
+			break;
 #else
 		case Opt_compress_algorithm:
 		case Opt_compress_log_size:
 		case Opt_compress_extension:
 		case Opt_compress_chksum:
 		case Opt_compress_mode:
+		case Opt_compress_cache:
 			f2fs_info(sbi, "compression options not supported");
 			break;
 #endif
@@ -1409,6 +1415,8 @@ static void f2fs_put_super(struct super_block *sb)
 
 	f2fs_bug_on(sbi, sbi->fsync_node_num);
 
+	f2fs_destroy_compress_inode(sbi);
+
 	iput(sbi->node_inode);
 	sbi->node_inode = NULL;
 
@@ -1678,6 +1686,9 @@ static inline void f2fs_show_compress_options(struct seq_file *seq,
 		seq_printf(seq, ",compress_mode=%s", "fs");
 	else if (F2FS_OPTION(sbi).compress_mode == COMPR_MODE_USER)
 		seq_printf(seq, ",compress_mode=%s", "user");
+
+	if (test_opt(sbi, COMPRESS_CACHE))
+		seq_puts(seq, ",compress_cache");
 }
 #endif
 
@@ -1959,6 +1970,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 	bool disable_checkpoint = test_opt(sbi, DISABLE_CHECKPOINT);
 	bool no_io_align = !F2FS_IO_ALIGNED(sbi);
 	bool no_atgc = !test_opt(sbi, ATGC);
+	bool no_compress_cache = !test_opt(sbi, COMPRESS_CACHE);
 	bool checkpoint_changed;
 #ifdef CONFIG_QUOTA
 	int i, j;
@@ -2056,6 +2068,12 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 		goto restore_opts;
 	}
 
+	if (no_compress_cache == !!test_opt(sbi, COMPRESS_CACHE)) {
+		err = -EINVAL;
+		f2fs_warn(sbi, "switch compress_cache option is not allowed");
+		goto restore_opts;
+	}
+
 	if ((*flags & SB_RDONLY) && test_opt(sbi, DISABLE_CHECKPOINT)) {
 		err = -EINVAL;
 		f2fs_warn(sbi, "disabling checkpoint not compatible with read-only");
@@ -3965,10 +3983,14 @@ try_onemore:
 		goto free_node_inode;
 	}
 
-	err = f2fs_register_sysfs(sbi);
+	err = f2fs_init_compress_inode(sbi);
 	if (err)
 		goto free_root_inode;
 
+	err = f2fs_register_sysfs(sbi);
+	if (err)
+		goto free_compress_inode;
+
 #ifdef CONFIG_QUOTA
 	/* Enable quota usage during mount */
 	if (f2fs_sb_has_quota_ino(sbi) && !f2fs_readonly(sb)) {
@@ -4109,6 +4131,8 @@ free_meta:
 	/* evict some inodes being cached by GC */
 	evict_inodes(sb);
 	f2fs_unregister_sysfs(sbi);
+free_compress_inode:
+	f2fs_destroy_compress_inode(sbi);
 free_root_inode:
 	dput(sb->s_root);
 	sb->s_root = NULL;
@@ -4187,6 +4211,15 @@ static void kill_f2fs_super(struct super_block *sb)
 		f2fs_stop_gc_thread(sbi);
 		f2fs_stop_discard_thread(sbi);
 
+#ifdef CONFIG_F2FS_FS_COMPRESSION
+		/*
+		 * latter evict_inode() can bypass checking and invalidating
+		 * compress inode cache.
+		 */
+		if (test_opt(sbi, COMPRESS_CACHE))
+			truncate_inode_pages_final(COMPRESS_MAPPING(sbi));
+#endif
+
 		if (is_sbi_flag_set(sbi, SBI_IS_DIRTY) ||
 				!is_set_ckpt_flags(sbi, CP_UMOUNT_FLAG)) {
 			struct cp_control cpc = {