[RFC PATCH v6 3/7] erofs: support domain-specific page cache share

[Hongzhen Luo <hongzhen@linux.alibaba.com>]

Only files in the same domain will share the page cache. Also modify
the sysfs related content in preparation for the upcoming page cache
share feature.

Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com>
---
 fs/erofs/super.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 6af02cc8b8c6..ceab0c29b061 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -489,6 +489,8 @@ static int erofs_fc_parse_param(struct fs_context *fc,
 		if (!sbi->fsid)
 			return -ENOMEM;
 		break;
+#endif
+#if defined(CONFIG_EROFS_FS_ONDEMAND) || defined(CONFIG_EROFS_FS_INODE_SHARE)
 	case Opt_domain_id:
 		kfree(sbi->domain_id);
 		sbi->domain_id = kstrdup(param->string, GFP_KERNEL);
@@ -558,16 +560,16 @@ static void erofs_set_sysfs_name(struct super_block *sb)
 {
 	struct erofs_sb_info *sbi = EROFS_SB(sb);
 
-	if (sbi->domain_id)
+	if (sbi->domain_id && !sbi->ishare_key)
 		super_set_sysfs_name_generic(sb, "%s,%s", sbi->domain_id,
 					     sbi->fsid);
 	else if (sbi->fsid)
 		super_set_sysfs_name_generic(sb, "%s", sbi->fsid);
-	else if (erofs_is_fileio_mode(sbi))
+	else if (!sb->s_bdi || !sb->s_bdi->dev)
+		super_set_sysfs_name_id(sb);
+	else
 		super_set_sysfs_name_generic(sb, "%s",
 					     bdi_dev_name(sb->s_bdi));
-	else
-		super_set_sysfs_name_id(sb);
 }
 
 static int erofs_fc_fill_super(struct super_block *sb, struct fs_context *fc)
@@ -965,6 +967,8 @@ static int erofs_show_options(struct seq_file *seq, struct dentry *root)
 #ifdef CONFIG_EROFS_FS_ONDEMAND
 	if (sbi->fsid)
 		seq_printf(seq, ",fsid=%s", sbi->fsid);
+#endif
+#if defined(CONFIG_EROFS_FS_ONDEMAND) || defined(CONFIG_EROFS_FS_INODE_SHARE)
 	if (sbi->domain_id)
 		seq_printf(seq, ",domain_id=%s", sbi->domain_id);
 #endif
-- 
2.43.5