[PATCH v4 07/15] fs: drop i_crypt_info from struct inode

[Christian Brauner <brauner@xxxxxxxxxx>]

Now that all filesystems store the fscrypt data pointer in their private
inode, drop the data pointer from struct inode itself freeing up 8
bytes.

Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
 fs/crypto/keysetup.c    |  9 +++++----
 include/linux/fs.h      |  5 -----
 include/linux/fscrypt.h | 23 +++++++----------------
 3 files changed, 12 insertions(+), 25 deletions(-)

diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index 8fd89ce0b614..352d0cfda17d 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -799,10 +799,11 @@ void fscrypt_put_encryption_info(struct inode *inode)
 {
 	struct fscrypt_inode_info **crypt_info;
 
-	if (inode->i_sb->s_cop->inode_info_offs)
-		crypt_info = fscrypt_addr(inode);
-	else
-		crypt_info = &inode->i_crypt_info;
+	if (!IS_ENCRYPTED(inode))
+		return;
+	VFS_WARN_ON_ONCE(!inode->i_sb->s_cop);
+	VFS_WARN_ON_ONCE(!inode->i_sb->s_cop->inode_info_offs);
+	crypt_info = fscrypt_addr(inode);
 	put_crypt_info(*crypt_info);
 	*crypt_info = NULL;
 }
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 96c7925a6551..b76a10fc765b 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -72,7 +72,6 @@ struct swap_info_struct;
 struct seq_file;
 struct workqueue_struct;
 struct iov_iter;
-struct fscrypt_inode_info;
 struct fscrypt_operations;
 struct fsverity_info;
 struct fsverity_operations;
@@ -778,10 +777,6 @@ struct inode {
 	struct fsnotify_mark_connector __rcu	*i_fsnotify_marks;
 #endif
 
-#ifdef CONFIG_FS_ENCRYPTION
-	struct fscrypt_inode_info	*i_crypt_info;
-#endif
-
 #ifdef CONFIG_FS_VERITY
 	struct fsverity_info	*i_verity_info;
 #endif
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 123871dd394c..a62879456873 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -208,28 +208,21 @@ static inline struct fscrypt_inode_info **fscrypt_addr(const struct inode *inode
 static inline bool fscrypt_set_inode_info(struct inode *inode,
 					  struct fscrypt_inode_info *crypt_info)
 {
-	void *p;
-
 	/*
 	 * For existing inodes, multiple tasks may race to set ->i_crypt_info.
 	 * So use cmpxchg_release().  This pairs with the smp_load_acquire() in
 	 * fscrypt_get_inode_info().  I.e., here we publish ->i_crypt_info with
 	 * a RELEASE barrier so that other tasks can ACQUIRE it.
 	 */
-
-	if (inode->i_sb->s_cop->inode_info_offs)
-		p = cmpxchg_release(fscrypt_addr(inode), NULL, crypt_info);
-	else
-		p = cmpxchg_release(&inode->i_crypt_info, NULL, crypt_info);
-	return p == NULL;
+	return cmpxchg_release(fscrypt_addr(inode), NULL, crypt_info) == NULL;
 }
 
 static inline struct fscrypt_inode_info *
 fscrypt_get_inode_info_raw(const struct inode *inode)
 {
-	if (inode->i_sb->s_cop->inode_info_offs)
-		return *fscrypt_addr(inode);
-	return inode->i_crypt_info;
+	VFS_WARN_ON_ONCE(!inode->i_sb->s_cop);
+	VFS_WARN_ON_ONCE(!inode->i_sb->s_cop->inode_info_offs);
+	return *fscrypt_addr(inode);
 }
 
 static inline struct fscrypt_inode_info *
@@ -241,11 +234,9 @@ fscrypt_get_inode_info(const struct inode *inode)
 	 * a RELEASE barrier.  We need to use smp_load_acquire() here to safely
 	 * ACQUIRE the memory the other task published.
 	 */
-
-	if (inode->i_sb->s_cop->inode_info_offs)
-		return smp_load_acquire(fscrypt_addr(inode));
-
-	return smp_load_acquire(&inode->i_crypt_info);
+	VFS_WARN_ON_ONCE(!inode->i_sb->s_cop);
+	VFS_WARN_ON_ONCE(!inode->i_sb->s_cop->inode_info_offs);
+	return smp_load_acquire(fscrypt_addr(inode));
 }
 
 /**

-- 
2.47.2