diff mbox series

[v4,07/10] ext4: Move ext4_match_ci into libfs

Message ID 20220511193146.27526-8-krisman@collabora.com
State Superseded
Headers show
Series Clean up the case-insensitive lookup path | expand

Commit Message

Gabriel Krisman Bertazi May 11, 2022, 7:31 p.m. UTC
Matching case-insensitive names is a generic operation and can be shared
with f2fs.  Move it next to the rest of the shared casefold fs code.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
---
 fs/ext4/namei.c    | 62 +---------------------------------------------
 fs/libfs.c         | 61 +++++++++++++++++++++++++++++++++++++++++++++
 include/linux/fs.h |  3 +++
 3 files changed, 65 insertions(+), 61 deletions(-)

Comments

Eric Biggers May 12, 2022, 5:24 a.m. UTC | #1
On Wed, May 11, 2022 at 03:31:43PM -0400, Gabriel Krisman Bertazi wrote:
> Matching case-insensitive names is a generic operation and can be shared
> with f2fs.  Move it next to the rest of the shared casefold fs code.
> 
> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
> ---
>  fs/ext4/namei.c    | 62 +---------------------------------------------
>  fs/libfs.c         | 61 +++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/fs.h |  3 +++
>  3 files changed, 65 insertions(+), 61 deletions(-)

It might be a good idea to split this into two patches, one for the libfs part
and one for the ext4 part.  That would make sorting out the dependencies of this
series easier in case it doesn't all go in in one cycle.

> +/**
> + * generic_ci_match() - Match (case-insensitive) a name with a dirent.
> + * @parent: Inode of the parent of the dentry.
> + * @uname: name under lookup.
> + * @de_name: Dirent name.
> + * @de_name_len: dirent name length.
> + *
> + * Test whether a case-insensitive directory entry matches the filename
> + * being searched.
> + *
> + * Return: > 0 if the directory entry matches, 0 if it doesn't match, or
> + * < 0 on error.
> + */
> +int generic_ci_match(const struct inode *parent,
> +		     const struct unicode_name *uname,
> +		     u8 *de_name, size_t de_name_len)

de_name should be const, like it is in the f2fs version.  It does get cast away
temporarily when it is stored in a fscrypt_str, but it never gets modified (and
must not be) so const is appropriate.

- Eric
diff mbox series

Patch

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 708811525411..16fd0df5f8a8 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1318,66 +1318,6 @@  static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block)
 }
 
 #if IS_ENABLED(CONFIG_UNICODE)
-/**
- * ext4_match_ci() - Match (case-insensitive) a name with a dirent.
- * @parent: Inode of the parent of the dentry.
- * @uname: name under lookup.
- * @de_name: Dirent name.
- * @de_name_len: dirent name length.
- *
- * Test whether a case-insensitive directory entry matches the filename
- * being searched.
- *
- * Return: > 0 if the directory entry matches, 0 if it doesn't match, or
- * < 0 on error.
- */
-static int ext4_match_ci(const struct inode *parent,
-			 const struct unicode_name *uname,
-			 u8 *de_name, size_t de_name_len)
-{
-	const struct super_block *sb = parent->i_sb;
-	const struct unicode_map *um = sb->s_encoding;
-	struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len);
-	struct qstr entry = QSTR_INIT(de_name, de_name_len);
-	int ret, match = false;
-
-	if (IS_ENCRYPTED(parent)) {
-		const struct fscrypt_str encrypted_name =
-				FSTR_INIT(de_name, de_name_len);
-
-		decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL);
-		if (!decrypted_name.name)
-			return -ENOMEM;
-		ret = fscrypt_fname_disk_to_usr(parent, 0, 0, &encrypted_name,
-						&decrypted_name);
-		if (ret < 0)
-			goto out;
-		entry.name = decrypted_name.name;
-		entry.len = decrypted_name.len;
-	}
-
-	if (uname->folded_name->name)
-		ret = utf8_strncasecmp_folded(um, uname->folded_name, &entry);
-	else
-		ret = utf8_strncasecmp(um, uname->usr_name, &entry);
-
-	if (!ret)
-		match = true;
-	else if (ret < 0 && !sb_has_strict_encoding(sb)) {
-		/*
-		 * In non-strict mode, fallback to a byte comparison if
-		 * the names have invalid characters.
-		 */
-		ret = 0;
-		match = ((uname->usr_name->len == entry.len) &&
-			 !memcmp(uname->usr_name->name, entry.name, entry.len));
-	}
-
-out:
-	kfree(decrypted_name.name);
-	return (ret >= 0) ? match : ret;
-}
-
 int ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,
 				  struct ext4_filename *name)
 {
@@ -1451,7 +1391,7 @@  static bool ext4_match(struct inode *parent,
 		};
 		int ret;
 
-		ret = ext4_match_ci(parent, &u, de->name, de->name_len);
+		ret = generic_ci_match(parent, &u, de->name, de->name_len);
 		if (ret < 0) {
 			/*
 			 * Treat comparison errors as not a match.  The
diff --git a/fs/libfs.c b/fs/libfs.c
index 974125270a42..c14b3fa615f5 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1465,6 +1465,67 @@  static const struct dentry_operations generic_ci_dentry_ops = {
 	.d_hash = generic_ci_d_hash,
 	.d_compare = generic_ci_d_compare,
 };
+
+/**
+ * generic_ci_match() - Match (case-insensitive) a name with a dirent.
+ * @parent: Inode of the parent of the dentry.
+ * @uname: name under lookup.
+ * @de_name: Dirent name.
+ * @de_name_len: dirent name length.
+ *
+ * Test whether a case-insensitive directory entry matches the filename
+ * being searched.
+ *
+ * Return: > 0 if the directory entry matches, 0 if it doesn't match, or
+ * < 0 on error.
+ */
+int generic_ci_match(const struct inode *parent,
+		     const struct unicode_name *uname,
+		     u8 *de_name, size_t de_name_len)
+{
+	const struct super_block *sb = parent->i_sb;
+	const struct unicode_map *um = sb->s_encoding;
+	struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len);
+	struct qstr entry = QSTR_INIT(de_name, de_name_len);
+	int ret, match = false;
+
+	if (IS_ENCRYPTED(parent)) {
+		const struct fscrypt_str encrypted_name =
+			FSTR_INIT(de_name, de_name_len);
+
+		decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL);
+		if (!decrypted_name.name)
+			return -ENOMEM;
+		ret = fscrypt_fname_disk_to_usr(parent, 0, 0, &encrypted_name,
+						&decrypted_name);
+		if (ret < 0)
+			goto out;
+		entry.name = decrypted_name.name;
+		entry.len = decrypted_name.len;
+	}
+
+	if (uname->folded_name->name)
+		ret = utf8_strncasecmp_folded(um, uname->folded_name, &entry);
+	else
+		ret = utf8_strncasecmp(um, uname->usr_name, &entry);
+
+	if (!ret)
+		match = true;
+	else if (ret < 0 && !sb_has_strict_encoding(sb)) {
+		/*
+		 * In non-strict mode, fallback to a byte comparison if
+		 * the names have invalid characters.
+		 */
+		ret = 0;
+		match = ((uname->usr_name->len == entry.len) &&
+			 !memcmp(uname->usr_name->name, entry.name, entry.len));
+	}
+
+out:
+	kfree(decrypted_name.name);
+	return (ret >= 0) ? match : ret;
+}
+EXPORT_SYMBOL(generic_ci_match);
 #endif
 
 #ifdef CONFIG_FS_ENCRYPTION
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 3f76a18a5f40..6a750b8704c9 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3364,6 +3364,9 @@  struct unicode_name {
 };
 
 extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry);
+extern int generic_ci_match(const struct inode *parent,
+			    const struct unicode_name *uname, u8 *de_name,
+			    size_t de_name_len);
 
 #ifdef CONFIG_MIGRATION
 extern int buffer_migrate_page(struct address_space *,