ext4: Save error information to the superblock for analysis

Save number of file system errors, and the time function name, line
number, block number, and inode number of the first and most recent
errors reported on the file system in the superblock.

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

1 files changed, 16 insertions, 1 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 088938148f5c..6b96125e7255 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1011,9 +1011,24 @@ struct ext4_super_block {
                                               snapshot's future use */
         __le32  s_snapshot_list;        /* inode number of the head of the
                                            on-disk snapshot list */
-        __u32   s_reserved[155];        /* Padding to the end of the block */
+#define EXT4_S_ERR_START offsetof(struct ext4_super_block, s_error_count)
+        __le32  s_error_count;          /* number of fs errors */
+        __le32  s_first_error_time;     /* first time an error happened */
+        __le32  s_first_error_ino;      /* inode involved in first error */
+        __le64  s_first_error_block;    /* block involved of first error */
+        __u8    s_first_error_func[32]; /* function where the error happened */
+        __le32  s_first_error_line;     /* line number where error happened */
+        __le32  s_last_error_time;      /* most recent time of an error */
+        __le32  s_last_error_ino;       /* inode involved in last error */
+        __le32  s_last_error_line;      /* line number where error happened */
+        __le64  s_last_error_block;     /* block involved of last error */
+        __u8    s_last_error_func[32];  /* function where the error happened */
+#define EXT4_S_ERR_END offsetof(struct ext4_super_block, s_reserved)
+        __le32   s_reserved[128];        /* Padding to the end of the block */
 };
 
+#define EXT4_S_ERR_LEN (EXT4_S_ERR_END - EXT4_S_ERR_START)
+
 #ifdef __KERNEL__
 
 /*