ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h
This patch makes fast_commit.h byte by byte identical with
e2fsprogs/fast_commit.h. This will help us ensure that there are no
on-disk format inconsistencies between e2fsck and kernel ext4.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201120202232.2240293-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/fast_commit.h b/fs/ext4/fast_commit.h
index 3a6e5a1..b77f70f 100644
--- a/fs/ext4/fast_commit.h
+++ b/fs/ext4/fast_commit.h
@@ -3,6 +3,11 @@
#ifndef __FAST_COMMIT_H__
#define __FAST_COMMIT_H__
+/*
+ * Note this file is present in e2fsprogs/lib/ext2fs/fast_commit.h and
+ * linux/fs/ext4/fast_commit.h. These file should always be byte identical.
+ */
+
/* Fast commit tags */
#define EXT4_FC_TAG_ADD_RANGE 0x0001
#define EXT4_FC_TAG_DEL_RANGE 0x0002
@@ -50,7 +55,7 @@ struct ext4_fc_del_range {
struct ext4_fc_dentry_info {
__le32 fc_parent_ino;
__le32 fc_ino;
- u8 fc_dname[0];
+ __u8 fc_dname[0];
};
/* Value structure for EXT4_FC_TAG_INODE and EXT4_FC_TAG_INODE_PARTIAL. */
@@ -66,19 +71,6 @@ struct ext4_fc_tail {
};
/*
- * In memory list of dentry updates that are performed on the file
- * system used by fast commit code.
- */
-struct ext4_fc_dentry_update {
- int fcd_op; /* Type of update create / unlink / link */
- int fcd_parent; /* Parent inode number */
- int fcd_ino; /* Inode number */
- struct qstr fcd_name; /* Dirent name */
- unsigned char fcd_iname[DNAME_INLINE_LEN]; /* Dirent name string */
- struct list_head fcd_list;
-};
-
-/*
* Fast commit reason codes
*/
enum {
@@ -107,6 +99,20 @@ enum {
EXT4_FC_REASON_MAX
};
+#ifdef __KERNEL__
+/*
+ * In memory list of dentry updates that are performed on the file
+ * system used by fast commit code.
+ */
+struct ext4_fc_dentry_update {
+ int fcd_op; /* Type of update create / unlink / link */
+ int fcd_parent; /* Parent inode number */
+ int fcd_ino; /* Inode number */
+ struct qstr fcd_name; /* Dirent name */
+ unsigned char fcd_iname[DNAME_INLINE_LEN]; /* Dirent name string */
+ struct list_head fcd_list;
+};
+
struct ext4_fc_stats {
unsigned int fc_ineligible_reason_count[EXT4_FC_REASON_MAX];
unsigned long fc_num_commits;
@@ -145,13 +151,51 @@ struct ext4_fc_replay_state {
};
#define region_last(__region) (((__region)->lblk) + ((__region)->len) - 1)
+#endif
#define fc_for_each_tl(__start, __end, __tl) \
- for (tl = (struct ext4_fc_tl *)start; \
- (u8 *)tl < (u8 *)end; \
- tl = (struct ext4_fc_tl *)((u8 *)tl + \
+ for (tl = (struct ext4_fc_tl *)(__start); \
+ (__u8 *)tl < (__u8 *)(__end); \
+ tl = (struct ext4_fc_tl *)((__u8 *)tl + \
sizeof(struct ext4_fc_tl) + \
+ le16_to_cpu(tl->fc_len)))
+static inline const char *tag2str(__u16 tag)
+{
+ switch (tag) {
+ case EXT4_FC_TAG_LINK:
+ return "ADD_ENTRY";
+ case EXT4_FC_TAG_UNLINK:
+ return "DEL_ENTRY";
+ case EXT4_FC_TAG_ADD_RANGE:
+ return "ADD_RANGE";
+ case EXT4_FC_TAG_CREAT:
+ return "CREAT_DENTRY";
+ case EXT4_FC_TAG_DEL_RANGE:
+ return "DEL_RANGE";
+ case EXT4_FC_TAG_INODE:
+ return "INODE";
+ case EXT4_FC_TAG_PAD:
+ return "PAD";
+ case EXT4_FC_TAG_TAIL:
+ return "TAIL";
+ case EXT4_FC_TAG_HEAD:
+ return "HEAD";
+ default:
+ return "ERROR";
+ }
+}
+
+/* Get length of a particular tlv */
+static inline int ext4_fc_tag_len(struct ext4_fc_tl *tl)
+{
+ return le16_to_cpu(tl->fc_len);
+}
+
+/* Get a pointer to "value" of a tlv */
+static inline __u8 *ext4_fc_tag_val(struct ext4_fc_tl *tl)
+{
+ return (__u8 *)tl + sizeof(*tl);
+}
#endif /* __FAST_COMMIT_H__ */