[PATCH v8 7/8] fscrypt: Have filesystems handle their d_ops

Daniel Rosenberg
2020-03-07T02:37:07Z

This shifts the responsibility of setting up dentry operations from
fscrypt to the individual filesystems, allowing them to have their own
operations while still setting fscrypt's d_revalidate as appropriate.

Most filesystems can just use generic_set_encrypted_ci_d_ops, unless
they have their own specific dentry operations as well. That operation
will set the minimal d_ops required under the circumstances.

Since the fscrypt d_ops are set later on, we must set all d_ops there,
since we cannot adjust those later on. This should not result in any
change in behavior.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
---
fs/crypto/fname.c | 4 ----
fs/crypto/fscrypt_private.h | 1 -
fs/crypto/hooks.c | 1 -
fs/ext4/dir.c | 7 -------
fs/ext4/ext4.h | 4 ----
fs/ext4/namei.c | 1 +
fs/ext4/super.c | 5 -----
fs/f2fs/dir.c | 7 -------
fs/f2fs/f2fs.h | 3 ---
fs/f2fs/namei.c | 1 +
fs/f2fs/super.c | 1 -
fs/ubifs/dir.c | 1 +
include/linux/fscrypt.h | 5 +++--
13 files changed, 6 insertions(+), 35 deletions(-)

diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 73adbbb9d78c7..14c585f66f8da 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -582,8 +582,4 @@ int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)

return valid;
}
-
-const struct dentry_operations fscrypt_d_ops = {
- .d_revalidate = fscrypt_d_revalidate,
-};
EXPORT_SYMBOL(fscrypt_d_revalidate);
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 9aae851409e55..238075fcabb3e 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -250,7 +250,6 @@ extern int fscrypt_fname_encrypt(const struct inode *inode,
extern bool fscrypt_fname_encrypted_size(const struct inode *inode,
u32 orig_len, u32 max_len,
u32 *encrypted_len_ret);
-extern const struct dentry_operations fscrypt_d_ops;

/* hkdf.c */

diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c
index 5ef861742921c..604a028dee25a 100644
--- a/fs/crypto/hooks.c
+++ b/fs/crypto/hooks.c
@@ -118,7 +118,6 @@ int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry,
spin_lock(&dentry->d_lock);
dentry->d_flags |= DCACHE_ENCRYPTED_NAME;
spin_unlock(&dentry->d_lock);
- d_set_d_op(dentry, &fscrypt_d_ops);
}
return err;
}
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 04fd68c4adc5f..b31780cae9c1f 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -667,10 +667,3 @@ const struct file_operations ext4_dir_operations = {
.open = ext4_dir_open,
.release = ext4_release_dir,
};
-
-#ifdef CONFIG_UNICODE
-const struct dentry_operations ext4_dentry_ops = {
- .d_hash = generic_ci_d_hash,
- .d_compare = generic_ci_d_compare,
-};
-#endif
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index b912c5611ddad..a01a507731d41 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3169,10 +3169,6 @@ static inline void ext4_unlock_group(struct super_block *sb,
/* dir.c */
extern const struct file_operations ext4_dir_operations;

-#ifdef CONFIG_UNICODE
-extern const struct dentry_operations ext4_dentry_ops;
-#endif
-
/* file.c */
extern const struct inode_operations ext4_file_inode_operations;
extern const struct file_operations ext4_file_operations;
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 1a1c4fdcfd3ee..001fdb0da477e 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1615,6 +1615,7 @@ static struct buffer_head *ext4_lookup_entry(struct inode *dir,
struct buffer_head *bh;

err = ext4_fname_prepare_lookup(dir, dentry, &fname);
+ generic_set_encrypted_ci_d_ops(dir, dentry);
if (err == -ENOENT)
return NULL;
if (err)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 11a7af11d8aee..c732122b25739 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4570,11 +4570,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
goto failed_mount4;
}

-#ifdef CONFIG_UNICODE
- if (sb->s_encoding)
- sb->s_d_op = &ext4_dentry_ops;
-#endif
-
sb->s_root = d_make_root(root);
if (!sb->s_root) {
ext4_msg(sb, KERN_ERR, "get root dentry failed");
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index d822c0d5eb182..38c0e6d589be4 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -1077,10 +1077,3 @@ const struct file_operations f2fs_dir_operations = {
.compat_ioctl = f2fs_compat_ioctl,
#endif
};
-
-#ifdef CONFIG_UNICODE
-const struct dentry_operations f2fs_dentry_ops = {
- .d_hash = generic_ci_d_hash,
- .d_compare = generic_ci_d_compare,
-};
-#endif
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index e73b8752f9c8d..0fc153b5a5c09 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3626,9 +3626,6 @@ static inline void update_sit_info(struct f2fs_sb_info *sbi) {}
#endif

extern const struct file_operations f2fs_dir_operations;
-#ifdef CONFIG_UNICODE
-extern const struct dentry_operations f2fs_dentry_ops;
-#endif
extern const struct file_operations f2fs_file_operations;
extern const struct inode_operations f2fs_file_inode_operations;
extern const struct address_space_operations f2fs_dblock_aops;
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 2aa035422c0fa..24d68eafffa40 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -494,6 +494,7 @@ static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
}

err = fscrypt_prepare_lookup(dir, dentry, &fname);
+ generic_set_encrypted_ci_d_ops(dir, dentry);
if (err == -ENOENT)
goto out_splice;
if (err)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 89b52629bd437..7520a9c04c75e 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -3256,7 +3256,6 @@ static int f2fs_setup_casefold(struct f2fs_sb_info *sbi)

sbi->sb->s_encoding = encoding;
sbi->sb->s_encoding_flags = encoding_flags;
- sbi->sb->s_d_op = &f2fs_dentry_ops;
}
#else
if (f2fs_sb_has_casefold(sbi)) {
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index ef85ec167a843..dc3af703db30d 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -209,6 +209,7 @@ static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
dbg_gen("'%pd' in dir ino %lu", dentry, dir->i_ino);

err = fscrypt_prepare_lookup(dir, dentry, &nm);
+ generic_set_encrypted_ci_d_ops(dir, dentry);
if (err == -ENOENT)
return d_splice_alias(NULL, dentry);
if (err)
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index b199b6e976ce3..f99e402abb540 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -596,8 +596,9 @@ static inline int fscrypt_prepare_rename(struct inode *old_dir,
* filenames are presented in encrypted form. Therefore, we'll try to set up
* the directory's encryption key, but even without it the lookup can continue.
*
- * This also installs a custom ->d_revalidate() method which will invalidate the
- * dentry if it was created without the key and the key is later added.
+ * After calling this function, a filesystem should ensure that its dentry
+ * operations contain fscrypt_d_revalidate if DCACHE_ENCRYPTED_NAME was set,
+ * so that the dentry can be invalidated if the key is later added.
*
* Return: 0 on success; -ENOENT if key is unavailable but the filename isn't a
* correctly formed encoded ciphertext name, so a negative dentry should be
--
2.25.1.481.gfbce0eb801-goog