linux-ext4 - [PATCH v4 5/7] libfs: Merge encrypted_ci_dentry_ops and ci_dentry

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Message-ID: <20230727172843.20542-6-krisman@suse.de>
Date:   Thu, 27 Jul 2023 13:28:41 -0400
From:   Gabriel Krisman Bertazi <krisman@...e.de>
To:     viro@...iv.linux.org.uk, brauner@...nel.org, tytso@....edu,
        ebiggers@...nel.org, jaegeuk@...nel.org
Cc:     linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net,
        Gabriel Krisman Bertazi <krisman@...e.de>,
        Gabriel Krisman Bertazi <krisman@...labora.com>
Subject: [PATCH v4 5/7] libfs: Merge encrypted_ci_dentry_ops and ci_dentry_ops

From: Gabriel Krisman Bertazi <krisman@...labora.com>

Now that casefold needs d_revalidate and calls fscrypt_d_revalidate
itself, generic_encrypt_ci_dentry_ops and generic_ci_dentry_ops are now
equivalent.  Merge them together and simplify the setup code.

Signed-off-by: Gabriel Krisman Bertazi <krisman@...labora.com>

---
changes since v2:
  - reword comment for clarity (Eric)
---
 fs/libfs.c | 45 +++++++++++++--------------------------------
 1 file changed, 13 insertions(+), 32 deletions(-)

diff --git a/fs/libfs.c b/fs/libfs.c
index 44c02993adb4..957dd12c1f25 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1516,7 +1516,7 @@ static inline int generic_ci_d_revalidate(struct dentry *dentry,
 	return fscrypt_d_revalidate(dentry, flags);
 }
 
-static const struct dentry_operations generic_ci_dentry_ops = {
+static const struct dentry_operations generic_encrypted_ci_dentry_ops = {
 	.d_hash = generic_ci_d_hash,
 	.d_compare = generic_ci_d_compare,
 	.d_revalidate_name = generic_ci_d_revalidate,
@@ -1529,26 +1529,19 @@ static const struct dentry_operations generic_encrypted_dentry_ops = {
 };
 #endif
 
-#if defined(CONFIG_FS_ENCRYPTION) && IS_ENABLED(CONFIG_UNICODE)
-static const struct dentry_operations generic_encrypted_ci_dentry_ops = {
-	.d_hash = generic_ci_d_hash,
-	.d_compare = generic_ci_d_compare,
-	.d_revalidate_name = generic_ci_d_revalidate,
-};
-#endif
-
 /**
  * generic_set_encrypted_ci_d_ops - helper for setting d_ops for given dentry
  * @dentry:	dentry to set ops on
  *
- * Casefolded directories need d_hash and d_compare set, so that the dentries
- * contained in them are handled case-insensitively.  Note that these operations
- * are needed on the parent directory rather than on the dentries in it, and
- * while the casefolding flag can be toggled on and off on an empty directory,
- * dentry_operations can't be changed later.  As a result, if the filesystem has
- * casefolding support enabled at all, we have to give all dentries the
- * casefolding operations even if their inode doesn't have the casefolding flag
- * currently (and thus the casefolding ops would be no-ops for now).
+ * Casefolded directories need some dentry_operations set, so that the dentries
+ * contained in them are handled case-insensitively.  Note that d_hash and
+ * d_compare are needed on the parent directory rather than on the dentries in
+ * it, and while the casefolding flag can be toggled on and off on an empty
+ * directory, dentry_operations can't be changed later.  As a result, if the
+ * filesystem has casefolding support enabled at all, we have to give all
+ * dentries the casefolding operations even if their inode doesn't have the
+ * casefolding flag currently (and thus the casefolding ops would be no-ops for
+ * now).
  *
  * Encryption works differently in that the only dentry operation it needs is
  * d_revalidate, which it only needs on dentries that have the no-key name flag.
@@ -1557,34 +1550,22 @@ static const struct dentry_operations generic_encrypted_ci_dentry_ops = {
  * Finally, to maximize compatibility with overlayfs (which isn't compatible
  * with certain dentry operations) and to avoid taking an unnecessary
  * performance hit, we use custom dentry_operations for each possible
- * combination rather than always installing all operations.
+ * combination of operations rather than always installing them.
  */
 void generic_set_encrypted_ci_d_ops(struct dentry *dentry)
 {
-#ifdef CONFIG_FS_ENCRYPTION
-	bool needs_encrypt_ops = dentry->d_flags & DCACHE_NOKEY_NAME;
-#endif
 #if IS_ENABLED(CONFIG_UNICODE)
-	bool needs_ci_ops = dentry->d_sb->s_encoding;
-#endif
-#if defined(CONFIG_FS_ENCRYPTION) && IS_ENABLED(CONFIG_UNICODE)
-	if (needs_encrypt_ops && needs_ci_ops) {
+	if (dentry->d_sb->s_encoding) {
 		d_set_d_op(dentry, &generic_encrypted_ci_dentry_ops);
 		return;
 	}
 #endif
 #ifdef CONFIG_FS_ENCRYPTION
-	if (needs_encrypt_ops) {
+	if (dentry->d_flags & DCACHE_NOKEY_NAME) {
 		d_set_d_op(dentry, &generic_encrypted_dentry_ops);
 		return;
 	}
 #endif
-#if IS_ENABLED(CONFIG_UNICODE)
-	if (needs_ci_ops) {
-		d_set_d_op(dentry, &generic_ci_dentry_ops);
-		return;
-	}
-#endif
 }
 EXPORT_SYMBOL(generic_set_encrypted_ci_d_ops);
 
-- 
2.41.0