nilfs2: separate read method of meta data files on super root block

Will displace nilfs_mdt_read_inode_direct function with an individual
read method: nilfs_dat_read, nilfs_sufile_read, nilfs_cpfile_read.

This provides the opportunity to initialize local variables of each
metadata file after reading the inode.
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

fs/nilfs2/cpfile.c

@@ -927,6 +927,16 @@ int nilfs_cpfile_get_stat(struct inode *cpfile, struct nilfs_cpstat *cpstat)
 	return ret;
 }
 
+/**
+ * nilfs_cpfile_read - read cpfile inode
+ * @cpfile: cpfile inode
+ * @raw_inode: on-disk cpfile inode
+ */
+int nilfs_cpfile_read(struct inode *cpfile, struct nilfs_inode *raw_inode)
+{
+	return nilfs_read_inode_common(cpfile, raw_inode);
+}
+
 /**
  * nilfs_cpfile_new - create cpfile
  * @nilfs: nilfs object

fs/nilfs2/cpfile.h

@@ -40,6 +40,7 @@ int nilfs_cpfile_get_stat(struct inode *, struct nilfs_cpstat *);
 ssize_t nilfs_cpfile_get_cpinfo(struct inode *, __u64 *, int, void *, unsigned,
 				size_t);
 
+int nilfs_cpfile_read(struct inode *cpfile, struct nilfs_inode *raw_inode);
 struct inode *nilfs_cpfile_new(struct the_nilfs *nilfs, size_t cpsize);
 
 #endif	/* _NILFS_CPFILE_H */

fs/nilfs2/dat.c

@@ -426,6 +426,16 @@ ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz,
 	return nvi;
 }
 
+/**
+ * nilfs_dat_read - read dat inode
+ * @dat: dat inode
+ * @raw_inode: on-disk dat inode
+ */
+int nilfs_dat_read(struct inode *dat, struct nilfs_inode *raw_inode)
+{
+	return nilfs_read_inode_common(dat, raw_inode);
+}
+
 /**
  * nilfs_dat_new - create dat file
  * @nilfs: nilfs object

fs/nilfs2/dat.h

@@ -53,6 +53,7 @@ int nilfs_dat_freev(struct inode *, __u64 *, size_t);
 int nilfs_dat_move(struct inode *, __u64, sector_t);
 ssize_t nilfs_dat_get_vinfo(struct inode *, void *, unsigned, size_t);
 
+int nilfs_dat_read(struct inode *dat, struct nilfs_inode *raw_inode);
 struct inode *nilfs_dat_new(struct the_nilfs *nilfs, size_t entry_size);
 
 #endif	/* _NILFS_DAT_H */

fs/nilfs2/sufile.c

@@ -658,6 +658,16 @@ ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum, void *buf,
 	return ret;
 }
 
+/**
+ * nilfs_sufile_read - read sufile inode
+ * @sufile: sufile inode
+ * @raw_inode: on-disk sufile inode
+ */
+int nilfs_sufile_read(struct inode *sufile, struct nilfs_inode *raw_inode)
+{
+	return nilfs_read_inode_common(sufile, raw_inode);
+}
+
 /**
  * nilfs_sufile_new - create sufile
  * @nilfs: nilfs object

fs/nilfs2/sufile.h

@@ -62,6 +62,7 @@ void nilfs_sufile_do_cancel_free(struct inode *, __u64, struct buffer_head *,
 void nilfs_sufile_do_set_error(struct inode *, __u64, struct buffer_head *,
 			       struct buffer_head *);
 
+int nilfs_sufile_read(struct inode *sufile, struct nilfs_inode *raw_inode);
 struct inode *nilfs_sufile_new(struct the_nilfs *nilfs, size_t susize);
 
 /**

fs/nilfs2/the_nilfs.c

@@ -204,18 +204,18 @@ static int nilfs_load_super_root(struct the_nilfs *nilfs,
 
 	nilfs_mdt_set_shadow(nilfs->ns_dat, nilfs->ns_gc_dat);
 
-	err = nilfs_mdt_read_inode_direct(
-		nilfs->ns_dat, bh_sr, NILFS_SR_DAT_OFFSET(inode_size));
+	err = nilfs_dat_read(nilfs->ns_dat, (void *)bh_sr->b_data +
+			     NILFS_SR_DAT_OFFSET(inode_size));
 	if (unlikely(err))
 		goto failed_sufile;
 
-	err = nilfs_mdt_read_inode_direct(
-		nilfs->ns_cpfile, bh_sr, NILFS_SR_CPFILE_OFFSET(inode_size));
+	err = nilfs_cpfile_read(nilfs->ns_cpfile, (void *)bh_sr->b_data +
+				NILFS_SR_CPFILE_OFFSET(inode_size));
 	if (unlikely(err))
 		goto failed_sufile;
 
-	err = nilfs_mdt_read_inode_direct(
-		nilfs->ns_sufile, bh_sr, NILFS_SR_SUFILE_OFFSET(inode_size));
+	err = nilfs_sufile_read(nilfs->ns_sufile, (void *)bh_sr->b_data +
+				NILFS_SR_SUFILE_OFFSET(inode_size));
 	if (unlikely(err))
 		goto failed_sufile;