ext4 crypto: enable encryption feature flag

Also add the test dummy encryption mode flag so we can more easily
test the encryption patches using xfstests.

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 28 insertions, 1 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 1008ca258de4..f9ebd58f40dd 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1106,7 +1106,7 @@ enum {
         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
-        Opt_data_err_abort, Opt_data_err_ignore,
+        Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
@@ -1197,6 +1197,7 @@ static const match_table_t tokens = {
         {Opt_init_itable, "init_itable"},
         {Opt_noinit_itable, "noinit_itable"},
         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
+        {Opt_test_dummy_encryption, "test_dummy_encryption"},
         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
@@ -1398,6 +1399,7 @@ static const struct mount_opts {
         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
+        {Opt_test_dummy_encryption, 0, MOPT_GTE0},
         {Opt_err, 0, 0}
 };
 
@@ -1574,6 +1576,15 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
                 }
                 *journal_ioprio =
                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
+        } else if (token == Opt_test_dummy_encryption) {
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+                sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
+                ext4_msg(sb, KERN_WARNING,
+                         "Test dummy encryption mode enabled");
+#else
+                ext4_msg(sb, KERN_WARNING,
+                         "Test dummy encryption mount option ignored");
+#endif
         } else if (m->flags & MOPT_DATAJ) {
                 if (is_remount) {
                         if (!sbi->s_journal)
@@ -2671,11 +2682,13 @@ static struct attribute *ext4_attrs[] = {
 EXT4_INFO_ATTR(lazy_itable_init);
 EXT4_INFO_ATTR(batched_discard);
 EXT4_INFO_ATTR(meta_bg_resize);
+EXT4_INFO_ATTR(encryption);
 
 static struct attribute *ext4_feat_attrs[] = {
         ATTR_LIST(lazy_itable_init),
         ATTR_LIST(batched_discard),
         ATTR_LIST(meta_bg_resize),
+        ATTR_LIST(encryption),
         NULL,
 };
 
@@ -3683,6 +3696,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                 }
         }
 
+        if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT) &&
+            es->s_encryption_level) {
+                ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
+                         es->s_encryption_level);
+                goto failed_mount;
+        }
+
         if (sb->s_blocksize != blocksize) {
                 /* Validate the filesystem blocksize */
                 if (!sb_set_blocksize(sb, blocksize)) {
@@ -4045,6 +4065,13 @@ no_journal:
                 }
         }
 
+        if (unlikely(sbi->s_mount_flags & EXT4_MF_TEST_DUMMY_ENCRYPTION) &&
+            !(sb->s_flags & MS_RDONLY) &&
+            !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT)) {
+                EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_ENCRYPT);
+                ext4_commit_super(sb, 1);
+        }
+
         /*
          * Get the # of file system overhead blocks from the
          * superblock if present.