f2fs: fix checkpoint=disable:%u%%

When parsing the mount option, we don't have sbi->user_block_count.
Should do it after getting it.

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

fs/f2fs/f2fs.h

@@ -139,6 +139,7 @@ struct f2fs_mount_info {
 	int fs_mode;			/* fs mode: LFS or ADAPTIVE */
 	int bggc_mode;			/* bggc mode: off, on or sync */
 	bool test_dummy_encryption;	/* test dummy encryption */
+	block_t unusable_cap_perc;	/* percentage for cap */
 	block_t unusable_cap;		/* Amount of space allowed to be
 					 * unusable when disabling checkpoint
 					 */

fs/f2fs/super.c

@@ -284,6 +284,22 @@ static inline void limit_reserve_root(struct f2fs_sb_info *sbi)
 					   F2FS_OPTION(sbi).s_resgid));
 }
 
+static inline void adjust_unusable_cap_perc(struct f2fs_sb_info *sbi)
+{
+	if (!F2FS_OPTION(sbi).unusable_cap_perc)
+		return;
+
+	if (F2FS_OPTION(sbi).unusable_cap_perc == 100)
+		F2FS_OPTION(sbi).unusable_cap = sbi->user_block_count;
+	else
+		F2FS_OPTION(sbi).unusable_cap = (sbi->user_block_count / 100) *
+					F2FS_OPTION(sbi).unusable_cap_perc;
+
+	f2fs_info(sbi, "Adjust unusable cap for checkpoint=disable = %u / %u%%",
+			F2FS_OPTION(sbi).unusable_cap,
+			F2FS_OPTION(sbi).unusable_cap_perc);
+}
+
 static void init_once(void *foo)
 {
 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
@@ -785,12 +801,7 @@ static int parse_options(struct super_block *sb, char *options)
 				return -EINVAL;
 			if (arg < 0 || arg > 100)
 				return -EINVAL;
-			if (arg == 100)
-				F2FS_OPTION(sbi).unusable_cap =
-					sbi->user_block_count;
-			else
-				F2FS_OPTION(sbi).unusable_cap =
-					(sbi->user_block_count / 100) *	arg;
+			F2FS_OPTION(sbi).unusable_cap_perc = arg;
 			set_opt(sbi, DISABLE_CHECKPOINT);
 			break;
 		case Opt_checkpoint_disable_cap:
@@ -1840,6 +1851,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
 		(test_opt(sbi, POSIX_ACL) ? SB_POSIXACL : 0);
 
 	limit_reserve_root(sbi);
+	adjust_unusable_cap_perc(sbi);
 	*flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
 	return 0;
 restore_gc:
@@ -3516,6 +3528,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 	sbi->reserved_blocks = 0;
 	sbi->current_reserved_blocks = 0;
 	limit_reserve_root(sbi);
+	adjust_unusable_cap_perc(sbi);
 
 	for (i = 0; i < NR_INODE_TYPE; i++) {
 		INIT_LIST_HEAD(&sbi->inode_list[i]);