[PATCH 6/9] erofs-utils: add inode hash helper

[Jingbo Xu]

Add erofs_insert_ihash() helper inserting inode into inode hash table,
and erofs_cleanup_ihash() helper cleaning up inode hash table.

Also add prototypes of erofs_iget() and erofs_iget_by_nid() in the
header file.

Signed-off-by: Jingbo Xu <jefflexu at linux.alibaba.com>
---
 include/erofs/inode.h |  4 ++++
 lib/inode.c           | 22 +++++++++++++++++++---
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/include/erofs/inode.h b/include/erofs/inode.h
index e8a5670..aba2a94 100644
--- a/include/erofs/inode.h
+++ b/include/erofs/inode.h
@@ -25,6 +25,10 @@ u32 erofs_new_encode_dev(dev_t dev);
 unsigned char erofs_mode_to_ftype(umode_t mode);
 unsigned char erofs_ftype_to_dtype(unsigned int filetype);
 void erofs_inode_manager_init(void);
+void erofs_insert_ihash(struct erofs_inode *inode, dev_t dev, ino_t ino);
+void erofs_cleanup_ihash(void);
+struct erofs_inode *erofs_iget(dev_t dev, ino_t ino);
+struct erofs_inode *erofs_iget_by_nid(erofs_nid_t nid);
 unsigned int erofs_iput(struct erofs_inode *inode);
 erofs_nid_t erofs_lookupnid(struct erofs_inode *inode);
 struct erofs_dentry *erofs_d_alloc(struct erofs_inode *parent,
diff --git a/lib/inode.c b/lib/inode.c
index d54f84f..d82ea95 100644
--- a/lib/inode.c
+++ b/lib/inode.c
@@ -75,6 +75,24 @@ void erofs_inode_manager_init(void)
 		init_list_head(&inode_hashtable[i]);
 }
 
+void erofs_insert_ihash(struct erofs_inode *inode, dev_t dev, ino_t ino)
+{
+	list_add(&inode->i_hash,
+		 &inode_hashtable[(ino ^ dev) % NR_INODE_HASHTABLE]);
+}
+
+void erofs_cleanup_ihash(void)
+{
+	unsigned int i;
+	struct erofs_inode *inode, *n;
+
+	for (i = 0; i < NR_INODE_HASHTABLE; ++i) {
+		list_for_each_entry_safe(inode, n, &inode_hashtable[i], i_hash)
+			list_del_init(&inode->i_hash);
+		init_list_head(&inode_hashtable[i]);
+	}
+}
+
 /* get the inode from the (source) inode # */
 struct erofs_inode *erofs_iget(dev_t dev, ino_t ino)
 {
@@ -976,9 +994,7 @@ static int erofs_fill_inode(struct erofs_inode *inode, struct stat *st,
 		inode->inode_isize = sizeof(struct erofs_inode_compact);
 	}
 
-	list_add(&inode->i_hash,
-		 &inode_hashtable[(st->st_ino ^ st->st_dev) %
-				  NR_INODE_HASHTABLE]);
+	erofs_insert_ihash(inode, st->st_dev, st->st_ino);
 	return 0;
 }
 
-- 
2.19.1.6.gb485710b