eCryptfs: Cleanup and optimize ecryptfs_lookup_interpose()
ecryptfs_lookup_interpose() has turned into spaghetti code over the
years. This is an effort to clean it up.
- Shorten overly descriptive variable names such as ecryptfs_dentry
- Simplify gotos and error paths
- Create helper function for reading plaintext i_size from metadata
It also includes an optimization when reading i_size from the metadata.
A complete page-sized kmem_cache_alloc() was being done to read in 16
bytes of metadata. The buffer for that is now statically declared.
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index 72aa24a..8297dda 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -200,6 +200,8 @@
#define MAGIC_ECRYPTFS_MARKER 0x3c81b7f5
#define MAGIC_ECRYPTFS_MARKER_SIZE_BYTES 8 /* 4*2 */
#define ECRYPTFS_FILE_SIZE_BYTES (sizeof(u64))
+#define ECRYPTFS_SIZE_AND_MARKER_BYTES (ECRYPTFS_FILE_SIZE_BYTES \
+ + MAGIC_ECRYPTFS_MARKER_SIZE_BYTES)
#define ECRYPTFS_DEFAULT_CIPHER "aes"
#define ECRYPTFS_DEFAULT_KEY_BYTES 16
#define ECRYPTFS_DEFAULT_HASH "md5"
@@ -659,9 +661,8 @@
void ecryptfs_write_crypt_stat_flags(char *page_virt,
struct ecryptfs_crypt_stat *crypt_stat,
size_t *written);
-int ecryptfs_read_and_validate_header_region(char *data,
- struct inode *ecryptfs_inode);
-int ecryptfs_read_and_validate_xattr_region(char *page_virt,
+int ecryptfs_read_and_validate_header_region(struct inode *inode);
+int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
struct inode *inode);
u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes);
int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code);
