diff --git a/apfs_raw.h b/apfs_raw.h
index 20e8eae..2195e8a 100644
--- a/apfs_raw.h
+++ b/apfs_raw.h
@@ -268,6 +268,10 @@ struct apfs_phys_ext_val {
 #define APFS_FILE_EXTENT_LEN_MASK	0x00ffffffffffffffULL
 #define APFS_FILE_EXTENT_FLAG_MASK	0xff00000000000000ULL
 #define APFS_FILE_EXTENT_FLAG_SHIFT	56
+#define APFS_FILE_EXTENT_CRYPTO_FLAG	0x01	/* Made-up name */
+#define APFS_FILE_EXTENT_PREALLOCATED	0x02	/* Made-up name */
+#define APFS_VALID_FILE_EXTENT_FLAGS	(APFS_FILE_EXTENT_CRYPTO_FLAG \
+					| APFS_FILE_EXTENT_PREALLOCATED)
 
 /*
  * Put a bound on maximum file size so that a growing truncation will always
@@ -1051,13 +1055,19 @@ struct apfs_checkpoint_map_phys {
 #define APFS_FS_SPILLEDOVER			0x00000010LL
 #define APFS_FS_RUN_SPILLOVER_CLEANER		0x00000020LL
 #define APFS_FS_ALWAYS_CHECK_EXTENTREF		0x00000040LL
+#define APFS_FS_PREVIOUSLY_SEALED		0x00000080LL /* Made-up name */
+#define APFS_FS_PFK				0x00000100LL /* Made-up name */
+#define APFS_FS_UNKNOWN_200			0x00000200LL
 #define APFS_FS_FLAGS_VALID_MASK		(APFS_FS_UNENCRYPTED \
-					       | APFS_FS_EFFACEABLE \
-					       | APFS_FS_RESERVED_4 \
-					       | APFS_FS_ONEKEY \
-					       | APFS_FS_SPILLEDOVER \
-					       | APFS_FS_RUN_SPILLOVER_CLEANER \
-					       | APFS_FS_ALWAYS_CHECK_EXTENTREF)
+						| APFS_FS_EFFACEABLE \
+						| APFS_FS_RESERVED_4 \
+						| APFS_FS_ONEKEY \
+						| APFS_FS_SPILLEDOVER \
+						| APFS_FS_RUN_SPILLOVER_CLEANER \
+						| APFS_FS_ALWAYS_CHECK_EXTENTREF \
+						| APFS_FS_PREVIOUSLY_SEALED \
+						| APFS_FS_PFK \
+						| APFS_FS_UNKNOWN_200)
 
 #define APFS_FS_CRYPTOFLAGS			(APFS_FS_UNENCRYPTED \
 						| APFS_FS_EFFACEABLE \
@@ -1124,7 +1134,9 @@ struct apfs_checkpoint_map_phys {
 #define APFS_INCOMPAT_NORMALIZATION_INSENSITIVE	0x00000008LL
 #define APFS_INCOMPAT_INCOMPLETE_RESTORE	0x00000010LL
 #define APFS_INCOMPAT_SEALED_VOLUME		0x00000020LL
-#define APFS_INCOMPAT_RESERVED_40		0x00000040LL
+#define APFS_INCOMPAT_PFK			0x00000040LL /* Made-up name */
+#define APFS_INCOMPAT_EXTENT_PREALLOC_FLAG	0x00000080LL /* Made-up name */
+#define APFS_INCOMPAT_SECONDARY_FSROOT		0x00000100LL /* Made-up name */
 
 #define APFS_SUPPORTED_INCOMPAT_MASK (APFS_INCOMPAT_CASE_INSENSITIVE \
 				     | APFS_INCOMPAT_DATALESS_SNAPS \
@@ -1132,7 +1144,9 @@ struct apfs_checkpoint_map_phys {
 				     | APFS_INCOMPAT_NORMALIZATION_INSENSITIVE \
 				     | APFS_INCOMPAT_INCOMPLETE_RESTORE \
 				     | APFS_INCOMPAT_SEALED_VOLUME \
-				     | APFS_INCOMPAT_RESERVED_40)
+				     | APFS_INCOMPAT_PFK \
+				     | APFS_INCOMPAT_EXTENT_PREALLOC_FLAG \
+				     | APFS_INCOMPAT_SECONDARY_FSROOT)
 
 #define APFS_MODIFIED_NAMELEN	      32
 
@@ -1162,6 +1176,18 @@ struct apfs_modified_by {
 #define APFS_CRYPTO_RESERVED_5		5
 #define APFS_UNASSIGNED_CRYPTO_ID	(~0ULL)
 
+/* Doc id index flags. I'm making up the names for now. */
+#define APFS_DOC_ID_HAS_PREV_TREE	0x00000001
+#define APFS_DOC_ID_UNKNOWN_02		0x00000002
+#define APFS_DOC_ID_UNKNOWN_04		0x00000004
+#define APFS_DOC_ID_UNKNOWN_08		0x00000008
+#define APFS_DOC_ID_UNKNOWN_10		0x00000010
+#define APFS_DOC_ID_VALID_FLAGS		(APFS_DOC_ID_HAS_PREV_TREE \
+					| APFS_DOC_ID_UNKNOWN_02 \
+					| APFS_DOC_ID_UNKNOWN_04 \
+					| APFS_DOC_ID_UNKNOWN_08 \
+					| APFS_DOC_ID_UNKNOWN_10)
+
 /*
  * Structure used to store the encryption state
  */
@@ -1277,9 +1303,10 @@ enum {
 	APFS_XATTR_DATA_EMBEDDED	= 0x00000002,
 	APFS_XATTR_FILE_SYSTEM_OWNED	= 0x00000004,
 	APFS_XATTR_RESERVED_8		= 0x00000008,
+	APFS_XATTR_UNKNOWN_10		= 0x00000010,
 };
 
-#define APFS_XATTR_VALID_FLAGS 0x0000000f
+#define APFS_XATTR_VALID_FLAGS 0x0000001f
 
 /*
  * Structure of the value of an extended attributes record
diff --git a/super.c b/super.c
index 381fe5e..4da0a16 100644
--- a/super.c
+++ b/super.c
@@ -1295,8 +1295,16 @@ static int apfs_check_vol_features(struct super_block *sb)
 		apfs_warn(sb, "incomplete restore is not supported");
 		return -EINVAL;
 	}
-	if (features & APFS_INCOMPAT_RESERVED_40) {
-		apfs_warn(sb, "reserved incompatible feature flag is set");
+	if (features & APFS_INCOMPAT_PFK) {
+		apfs_warn(sb, "PFK is not supported");
+		return -EINVAL;
+	}
+	if (features & APFS_INCOMPAT_EXTENT_PREALLOC_FLAG) {
+		apfs_warn(sb, "extent prealloc flag is not supported");
+		return -EINVAL;
+	}
+	if (features & APFS_INCOMPAT_SECONDARY_FSROOT) {
+		apfs_warn(sb, "secondary fsroot is not supported");
 		return -EINVAL;
 	}
 	if (features & APFS_INCOMPAT_SEALED_VOLUME) {