ext4: reserve codepoints used by the ext4 encryption feature

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index a75fba6..b7f393d 100644 (file)
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -364,7 +364,8 @@ struct flex_groups {
 #define EXT4_DIRTY_FL                  0x00000100
 #define EXT4_COMPRBLK_FL               0x00000200 /* One or more compressed clusters */
 #define EXT4_NOCOMPR_FL                        0x00000400 /* Don't compress */
-#define EXT4_ECOMPR_FL                 0x00000800 /* Compression error */
+       /* nb: was previously EXT2_ECOMPR_FL */
+#define EXT4_ENCRYPT_FL                        0x00000800 /* encrypted file */
 /* End compression flags --- maybe not all used */
 #define EXT4_INDEX_FL                  0x00001000 /* hash-indexed directory */
 #define EXT4_IMAGIC_FL                 0x00002000 /* AFS directory */
@@ -421,7 +422,7 @@ enum {
        EXT4_INODE_DIRTY        = 8,
        EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
        EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
-       EXT4_INODE_ECOMPR       = 11,   /* Compression error */
+       EXT4_INODE_ENCRYPT      = 11,   /* Compression error */
 /* End compression flags --- maybe not all used */
        EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
        EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
@@ -466,7 +467,7 @@ static inline void ext4_check_flag_values(void)
        CHECK_FLAG_VALUE(DIRTY);
        CHECK_FLAG_VALUE(COMPRBLK);
        CHECK_FLAG_VALUE(NOCOMPR);
-       CHECK_FLAG_VALUE(ECOMPR);
+       CHECK_FLAG_VALUE(ENCRYPT);
        CHECK_FLAG_VALUE(INDEX);
        CHECK_FLAG_VALUE(IMAGIC);
        CHECK_FLAG_VALUE(JOURNAL_DATA);
@@ -1043,6 +1044,12 @@ extern void ext4_set_bits(void *bm, int cur, int len);
 /* Metadata checksum algorithm codes */
 #define EXT4_CRC32C_CHKSUM             1
 
+/* Encryption algorithms */
+#define EXT4_ENCRYPTION_MODE_INVALID           0
+#define EXT4_ENCRYPTION_MODE_AES_256_XTS       1
+#define EXT4_ENCRYPTION_MODE_AES_256_GCM       2
+#define EXT4_ENCRYPTION_MODE_AES_256_CBC       3
+
 /*
  * Structure of the super block
  */
@@ -1156,7 +1163,8 @@ struct ext4_super_block {
        __le32  s_grp_quota_inum;       /* inode for tracking group quota */
        __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
        __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
-       __le32  s_reserved[106];        /* Padding to the end of the block */
+       __u8    s_encrypt_algos[4];     /* Encryption algorithms in use  */
+       __le32  s_reserved[105];        /* Padding to the end of the block */
        __le32  s_checksum;             /* crc32c(superblock) */
 };
 
@@ -1537,6 +1545,7 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei)
 #define EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM 0x2000 /* use crc32c for bg */
 #define EXT4_FEATURE_INCOMPAT_LARGEDIR         0x4000 /* >2GB or 3-lvl htree */
 #define EXT4_FEATURE_INCOMPAT_INLINE_DATA      0x8000 /* data in inode */
+#define EXT4_FEATURE_INCOMPAT_ENCRYPT          0x10000
 
 #define EXT2_FEATURE_COMPAT_SUPP       EXT4_FEATURE_COMPAT_EXT_ATTR
 #define EXT2_FEATURE_INCOMPAT_SUPP     (EXT4_FEATURE_INCOMPAT_FILETYPE| \