scoutfs/utils/man/scoutfs-corruption.7

.TH scoutfs-corruption 7
.SH NAME
scoutfs-corruption \- corruption message details
.SH DESCRIPTION
If scoutfs detects corruption during operation it will output an error
message describing the corruption.  This document gives details of the
corruption described by the messages.
.SH CORRUPTION MESSAGE IDENTIFIERS
.TP
.B SC_DIRENT_NAME_LEN
A directory entry with an invalid name length was found during lookup.

Directory entries are stored in the values of metadata items.  The item
value contains a small header and the full entry name.  The length of
the entry name is calculated by substracting the size of the header from
the length of the item value.  This corruption is detected if the length
of the calculated name length is invalid by being less than 1 or greater
than 255.

.BR dir_ino " - inode number of directory that contains the item"
.br
.BR hash " - hash value of search name"
.br
.BR key " - identifies the item with the invalid name length"
.br
.BR len " - the invalid calculaged name length"
.sp
.TP
.B SC_DIRENT_READDIR_NAME_LEN
A directory entry with an invalid name length was found during readdir.

This corruption is very similar to
.B SC_DIRENT_NAME_LEN
except that the corruption is discovered during readdir instead of
lookup.  The readdir search key is formed from the file position instead
of from the hashed name as in lookup.   The dirent structure stored in
the item value is the same.

.BR dir_ino " - inode number of directory that contains the item"
.br
.BR pos " - the file position readdir was searching from"
.br
.BR key " - identifies the item with the invalid name length"
.br
.BR len " - the invalid calculaged name length"
.sp

.TP
.B SC_DIRENT_BACKREF_NAME_LEN
A directory entry with an invalid name length was found while finding
entries that point to an inode.

This corruption is very similar to
.B SC_DIRENT_NAME_LEN
except that the
corruption is discovered while finding entries that refer to a specific
inode.  The search key is formed from the inode and position of the
referring entry instead of from the hashed name as in lookup.   The
dirent structure stored in the item value is the same.

.BR ino " - target inode number we're finding entries to"
.br
.BR dir_ino " - inode number of directory containing entries to search"
.br
.BR pos " - position in directory containing entries to search"
.br
.BR key " - identifies the item with the invalid name length"
.br
.BR len " - the invalid calculaged name length"
.sp

.TP
.B SC_SYMLINK_INODE_SIZE
The items that contain a symlink target path weren't found.

The target path of a symlink is stored in a series of metadata items.
The number of items can be calculated from the size of the path.  While
trying to resolve a symlink one of the items wasn't found.

.BR ino " - inode number of the symlink with the invalid size"
.br
.BR size " - the invalid size found in the inode"
.sp

.TP
.B SC_SYMLINK_MISSING_ITEM
A symlink inode contained an invalid size.

The i_size field of the inode that stores a symlink records the length
of the path of the symlink target.  The path length can't be less than 1
or greater than the max size which is around 4KiB.

.BR ino " - inode number of the symlink with the invalid size"
.br
.BR size " - the length of the target path"
.sp

.TP
.B SC_SYMLINK_NOT_NULL_TERM
A symlink target path wasn't null terminated.

The target path stored in a symlink's metadata items wasn't null
terminated.

.BR ino " - inode number of the symlink with the invalid size"
.br
.BR last " - the value of the final byte of the path"
.sp

.TP
.B SC_BTREE_BLOCK_LEVEL
A btree block's header did not contain the expected level field.

The btree root stores the height of the btree and each btree block
stores its level in the tree.  During descent the level is loaded from
the root and decremented as each block is traveresed.  This corruption
occurs when a btree block's level field didn't match the level that was
being calculated during descent.

.BR root_height " - height of the tree in the root"
.br
.BR root_blkno " - block number of the first block in the root"
.br
.BR root_seq " - sequence number of the first block in the root"
.br
.BR blkno " - block number of the block with mismatched level"
.br
.BR seq " - sequence number of the block with mismatched level"
.br
.BR level " - level of the block with mismatched level"
.br
.BR expected " - expected level that was calculated during descent"
.sp

.TP
.B SC_BTREE_NO_CHILD_REF
A btree parent block didn't have a child item for a key.

Each child reference in a parent btree block contains the greatest key
that will be stored in the subtree rooted in the child.  The child
references down the right side of the tree must have a key that is
greater than all possible keys.

This corruption occurs during descent when the search key was greater
than the last child reference's key.

.BR root_height " - height of the tree in the root"
.br
.BR root_blkno " - block number of the first block in the root"
.br
.BR root_seq " - sequence number of the first block in the root"
.br
.BR blkno " - block number of the block with mismatched level"
.br
.BR seq " - sequence number of the block with mismatched level"
.br
.BR level " - level of the block with mismatched level"
.br
.BR nr " - number of items in the parent block"
.br
.BR pos " - child item index that search found"
.br
.BR cmp " - comparison of search key and found"
.sp

.SH AUTHORS
Zach Brown <zab@versity.com>