fscrypt: stop holding extra request_queue references

Now that the fscrypt_master_key lifetime has been reworked to not be
subject to the quirks of the keyrings subsystem, blk_crypto_evict_key()
no longer gets called after the filesystem has already been unmounted.
Therefore, there is no longer any need to hold extra references to the
filesystem's request_queue(s).  (And these references didn't always do
their intended job anyway, as pinning a request_queue doesn't
necessarily pin the corresponding blk_crypto_profile.)

Stop taking these extra references.  Instead, just pass the super_block
to fscrypt_destroy_inline_crypt_key(), and use it to get the list of
block devices the key needs to be evicted from.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20220901193208.138056-3-ebiggers@kernel.org

1 files changed, 7 insertions, 4 deletions

diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 577cae7facb0..d5f68a0c5d15 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -184,7 +184,7 @@ struct fscrypt_symlink_data {
 struct fscrypt_prepared_key {
 	struct crypto_skcipher *tfm;
 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
-	struct fscrypt_blk_crypto_key *blk_key;
+	struct blk_crypto_key *blk_key;
 #endif
 };
 
@@ -344,7 +344,8 @@ int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
 				     const u8 *raw_key,
 				     const struct fscrypt_info *ci);
 
-void fscrypt_destroy_inline_crypt_key(struct fscrypt_prepared_key *prep_key);
+void fscrypt_destroy_inline_crypt_key(struct super_block *sb,
+				      struct fscrypt_prepared_key *prep_key);
 
 /*
  * Check whether the crypto transform or blk-crypto key has been allocated in
@@ -390,7 +391,8 @@ fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
 }
 
 static inline void
-fscrypt_destroy_inline_crypt_key(struct fscrypt_prepared_key *prep_key)
+fscrypt_destroy_inline_crypt_key(struct super_block *sb,
+				 struct fscrypt_prepared_key *prep_key)
 {
 }
 
@@ -600,7 +602,8 @@ extern struct fscrypt_mode fscrypt_modes[];
 int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key,
 			const u8 *raw_key, const struct fscrypt_info *ci);
 
-void fscrypt_destroy_prepared_key(struct fscrypt_prepared_key *prep_key);
+void fscrypt_destroy_prepared_key(struct super_block *sb,
+				  struct fscrypt_prepared_key *prep_key);
 
 int fscrypt_set_per_file_enc_key(struct fscrypt_info *ci, const u8 *raw_key);