[RFC PATCH v3 15/18] ext4: wire up new fscrypt ioctls

[Eric Biggers <ebiggers@kernel.org>]

From: Eric Biggers <ebiggers@google.com>

Wire up the new ioctls for adding and removing fscrypt keys to/from the
filesystem, and the new ioctl for retrieving v2 encryption policies.

FS_IOC_REMOVE_ENCRYPTION_KEY also required making ext4_drop_inode() call
fscrypt_drop_inode().

For more details see Documentation/filesystems/fscrypt.rst, as well as
the fscrypt patches that added the implementation of these ioctls.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 fs/ext4/ioctl.c | 24 ++++++++++++++++++++++++
 fs/ext4/super.c |  3 +++
 2 files changed, 27 insertions(+)

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index d26bcac291bb..c939dbd2f2ac 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -1020,6 +1020,26 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	case EXT4_IOC_GET_ENCRYPTION_POLICY:
 		return fscrypt_ioctl_get_policy(filp, (void __user *)arg);
 
+	case FS_IOC_GET_ENCRYPTION_POLICY_EX:
+		if (!ext4_has_feature_encrypt(sb))
+			return -EOPNOTSUPP;
+		return fscrypt_ioctl_get_policy_ex(filp, (void __user *)arg);
+
+	case FS_IOC_ADD_ENCRYPTION_KEY:
+		if (!ext4_has_feature_encrypt(sb))
+			return -EOPNOTSUPP;
+		return fscrypt_ioctl_add_key(filp, (void __user *)arg);
+
+	case FS_IOC_REMOVE_ENCRYPTION_KEY:
+		if (!ext4_has_feature_encrypt(sb))
+			return -EOPNOTSUPP;
+		return fscrypt_ioctl_remove_key(filp, (const void __user *)arg);
+
+	case FS_IOC_GET_ENCRYPTION_KEY_STATUS:
+		if (!ext4_has_feature_encrypt(sb))
+			return -EOPNOTSUPP;
+		return fscrypt_ioctl_get_key_status(filp, (void __user *)arg);
+
 	case EXT4_IOC_FSGETXATTR:
 	{
 		struct fsxattr fa;
@@ -1138,6 +1158,10 @@ long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 	case EXT4_IOC_SET_ENCRYPTION_POLICY:
 	case EXT4_IOC_GET_ENCRYPTION_PWSALT:
 	case EXT4_IOC_GET_ENCRYPTION_POLICY:
+	case FS_IOC_GET_ENCRYPTION_POLICY_EX:
+	case FS_IOC_ADD_ENCRYPTION_KEY:
+	case FS_IOC_REMOVE_ENCRYPTION_KEY:
+	case FS_IOC_GET_ENCRYPTION_KEY_STATUS:
 	case EXT4_IOC_SHUTDOWN:
 	case FS_IOC_GETFSMAP:
 		break;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 60da0a6e4d86..5b260f88c19f 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1093,6 +1093,9 @@ static int ext4_drop_inode(struct inode *inode)
 {
 	int drop = generic_drop_inode(inode);
 
+	if (!drop)
+		drop = fscrypt_drop_inode(inode);
+
 	trace_ext4_drop_inode(inode, drop);
 	return drop;
 }
-- 
2.20.1