linux-ext4 - [PATCH v5 02/12] fscrypt: Factor out a helper to configure the lookup dentry

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Date: Mon, 29 Jan 2024 17:43:20 -0300
From: Gabriel Krisman Bertazi <krisman@...e.de>
To: ebiggers@...nel.org,
	viro@...iv.linux.org.uk,
	jaegeuk@...nel.org,
	tytso@....edu
Cc: amir73il@...il.com,
	linux-ext4@...r.kernel.org,
	linux-f2fs-devel@...ts.sourceforge.net,
	linux-fsdevel@...r.kernel.org,
	Gabriel Krisman Bertazi <krisman@...e.de>
Subject: [PATCH v5 02/12] fscrypt: Factor out a helper to configure the lookup dentry

Both fscrypt_prepare_lookup_dentry_partial and
fscrypt_prepare_lookup_dentry will set DCACHE_NOKEY_NAME for dentries
when the key is not available. Extract out a helper to set this flag in
a single place, in preparation to also add the optimization that will
disable ->d_revalidate if possible.

Signed-off-by: Gabriel Krisman Bertazi <krisman@...e.de>
---
 fs/crypto/hooks.c       | 18 ++++++++----------
 include/linux/fscrypt.h | 10 ++++++++++
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c
index 52504dd478d3..71463cef08f9 100644
--- a/fs/crypto/hooks.c
+++ b/fs/crypto/hooks.c
@@ -102,11 +102,8 @@ int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry,
 	if (err && err != -ENOENT)
 		return err;
 
-	if (fname->is_nokey_name) {
-		spin_lock(&dentry->d_lock);
-		dentry->d_flags |= DCACHE_NOKEY_NAME;
-		spin_unlock(&dentry->d_lock);
-	}
+	fscrypt_prepare_lookup_dentry(dentry, fname->is_nokey_name);
+
 	return err;
 }
 EXPORT_SYMBOL_GPL(__fscrypt_prepare_lookup);
@@ -131,12 +128,13 @@ EXPORT_SYMBOL_GPL(__fscrypt_prepare_lookup);
 int fscrypt_prepare_lookup_partial(struct inode *dir, struct dentry *dentry)
 {
 	int err = fscrypt_get_encryption_info(dir, true);
+	bool is_nokey_name = false;
+
+	if (!err && !fscrypt_has_encryption_key(dir))
+		is_nokey_name = true;
+
+	fscrypt_prepare_lookup_dentry(dentry, is_nokey_name);
 
-	if (!err && !fscrypt_has_encryption_key(dir)) {
-		spin_lock(&dentry->d_lock);
-		dentry->d_flags |= DCACHE_NOKEY_NAME;
-		spin_unlock(&dentry->d_lock);
-	}
 	return err;
 }
 EXPORT_SYMBOL_GPL(fscrypt_prepare_lookup_partial);
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 12f9e455d569..68ca8706483a 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -948,6 +948,16 @@ static inline int fscrypt_prepare_rename(struct inode *old_dir,
 	return 0;
 }
 
+static inline void fscrypt_prepare_lookup_dentry(struct dentry *dentry,
+						 bool is_nokey_name)
+{
+	if (is_nokey_name) {
+		spin_lock(&dentry->d_lock);
+		dentry->d_flags |= DCACHE_NOKEY_NAME;
+		spin_unlock(&dentry->d_lock);
+	}
+}
+
 /**
  * fscrypt_prepare_lookup() - prepare to lookup a name in a possibly-encrypted
  *			      directory
-- 
2.43.0