linux-kernel - [PATCH v6 03/16] fs: introduce alloc_inode_sb() to allocate filesystems specific inode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220228122126.37293-4-songmuchun@bytedance.com>
Date:   Mon, 28 Feb 2022 20:21:13 +0800
From:   Muchun Song <songmuchun@...edance.com>
To:     willy@...radead.org, akpm@...ux-foundation.org, hannes@...xchg.org,
        mhocko@...nel.org, vdavydov.dev@...il.com, shakeelb@...gle.com,
        roman.gushchin@...ux.dev, shy828301@...il.com, alexs@...nel.org,
        richard.weiyang@...il.com, david@...morbit.com,
        trond.myklebust@...merspace.com, anna.schumaker@...app.com,
        jaegeuk@...nel.org, chao@...nel.org, kari.argillander@...il.com,
        vbabka@...e.cz
Cc:     linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-mm@...ck.org, linux-nfs@...r.kernel.org,
        zhengqi.arch@...edance.com, duanxiongchun@...edance.com,
        fam.zheng@...edance.com, smuchun@...il.com,
        Muchun Song <songmuchun@...edance.com>
Subject: [PATCH v6 03/16] fs: introduce alloc_inode_sb() to allocate filesystems specific inode

The allocated inode cache is supposed to be added to its memcg list_lru
which should be allocated as well in advance. That can be done by
kmem_cache_alloc_lru() which allocates object and list_lru. The file
systems is main user of it. So introduce alloc_inode_sb() to allocate
file system specific inodes and set up the inode reclaim context
properly. The file system is supposed to use alloc_inode_sb() to
allocate inodes. In the later patches, we will convert all users to the
new API.

Signed-off-by: Muchun Song <songmuchun@...edance.com>
Reviewed-by: Roman Gushchin <roman.gushchin@...ux.dev>
---
 Documentation/filesystems/porting.rst |  6 ++++++
 fs/inode.c                            |  2 +-
 include/linux/fs.h                    | 11 +++++++++++
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst
index bf19fd6b86e7..7c1583dbeb59 100644
--- a/Documentation/filesystems/porting.rst
+++ b/Documentation/filesystems/porting.rst
@@ -45,6 +45,12 @@ typically between calling iget_locked() and unlocking the inode.
 
 At some point that will become mandatory.
 
+**mandatory**
+
+The foo_inode_info should always be allocated through alloc_inode_sb() rather
+than kmem_cache_alloc() or kmalloc() related to set up the inode reclaim context
+correctly.
+
 ---
 
 **mandatory**
diff --git a/fs/inode.c b/fs/inode.c
index 63324df6fa27..9d9b422504d1 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -259,7 +259,7 @@ static struct inode *alloc_inode(struct super_block *sb)
 	if (ops->alloc_inode)
 		inode = ops->alloc_inode(sb);
 	else
-		inode = kmem_cache_alloc(inode_cachep, GFP_KERNEL);
+		inode = alloc_inode_sb(sb, inode_cachep, GFP_KERNEL);
 
 	if (!inode)
 		return NULL;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e2d892b201b0..3d56b02667f4 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -42,6 +42,7 @@
 #include <linux/mount.h>
 #include <linux/cred.h>
 #include <linux/mnt_idmapping.h>
+#include <linux/slab.h>
 
 #include <asm/byteorder.h>
 #include <uapi/linux/fs.h>
@@ -3108,6 +3109,16 @@ extern void free_inode_nonrcu(struct inode *inode);
 extern int should_remove_suid(struct dentry *);
 extern int file_remove_privs(struct file *);
 
+/*
+ * This must be used for allocating filesystems specific inodes to set
+ * up the inode reclaim context correctly.
+ */
+static inline void *
+alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp)
+{
+	return kmem_cache_alloc_lru(cache, &sb->s_inode_lru, gfp);
+}
+
 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
 static inline void insert_inode_hash(struct inode *inode)
 {
-- 
2.11.0