1 btrfs-inspect-internal(8)
2 =========================
6 btrfs-inspect-internal - query various internal information
10 *btrfs inspect-internal* <subcommand> <args>
15 This command group provides an interface to query internal information. The
16 functionality ranges from a simple UI to an ioctl or a more complex query that
17 assembles the result from several internal structures. The latter usually
18 requires calls to privileged ioctls.
22 *dump-super* [options] <device> [device...]::
23 (needs root privileges)
25 Show btrfs superblock information stored in devices.
26 It is used to print the information of superblock,
27 you can specify which mirror to print out.
29 By default, every device's first superblock will be printed out.
31 Mainly used for debug purpose.
36 Print full superblock information.
38 Including the system chunk array and backup roots.
41 Print information of all superblocks.
43 If this option is given, '-i' option will be ignored.
46 Specify which mirror to print out.
48 <super_mirror> is between 0 and 2.
49 If several '-i <super_mirror>' are given, only the last one is valid.
52 Attempt to print the superblock even if no superblock magic is found. May end
55 specify offset to a superblock in a non-standard location at 'bytenr', useful
56 for debugging (disables the '-f' option)
58 *dump-tree* [options] <device>::
59 (replaces the standalone tool *btrfs-debug-tree*)
61 Dump tree structures from a given device in textual form, expand keys to human
62 readable equivalents where possible.
63 This is useful for analyzing filesystem state or inconsistencies and has
64 a positive educational effect on understanding the internal filesystem structure.
66 NOTE: contains file names, consider that if you're asked to send the dump for
67 analysis. Does not contain file data.
72 print only extent-related information: extent and device trees
74 print only device-related information: tree root, chunk and device trees
76 print only short root node information, ie. the root tree keys
78 same as --roots plus print backup root info, ie. the backup root keys and
79 the respective tree root block offset
81 print only the uuid tree information, empty output if the tree does not exist
83 print info of the specified block only
85 print only the tree with the specified ID, where the ID can be numerical or
86 common name in a flexible human readable form
88 The tree id name recognition rules:
90 * case does not matter
91 * the C source definition, eg. BTRFS_ROOT_TREE_OBJECTID
92 * short forms without BTRFS_ prefix, without _TREE and _OBJECTID suffix, eg. ROOT_TREE, ROOT
93 * convenience aliases, eg. DEVICE for the DEV tree, CHECKSUM for CSUM
94 * unrecognized ID is an error
96 *inode-resolve* [-v] <ino> <path>::
97 (needs root privileges)
99 resolve paths to all files with given inode number 'ino' in a given subvolume
100 at 'path', ie. all hardlinks
105 verbose mode, print count of returned paths and ioctl() return value
107 *logical-resolve* [-Pv] [-s <bufsize>] <logical> <path>::
108 (needs root privileges)
110 resolve paths to all files at given 'logical' address in the linear filesystem space
115 skip the path resolving and print the inodes instead
117 verbose mode, print count of returned paths and all ioctl() return values
119 set internal buffer for storing the file names to 'bufsize', default is 4096, maximum 64k
121 *min-dev-size* [options] <path>::
122 (needs root privileges)
124 return the minimum size the device can be shrunk to, without performing any
125 resize operation, this may be useful before executing the actual resize operation
130 specify the device 'id' to query, default is 1 if this option is not used
133 for a given file or directory, return the containing tree root id, for a
134 subvolume itself return it's own tree id (ie. subvol id)
136 NOTE: The result is undefined for the so-called empty subvolumes (identified by
137 inode number 2), but such subvolume does not contain any files anyway
139 *subvolid-resolve* <subvolid> <path>::
140 (needs root privileges)
142 resolve the absolute path of a the subvolume id 'subvolid'
146 *btrfs inspect-internal* returns a zero exit status if it succeeds. Non zero is
147 returned in case of failure.
151 *btrfs* is part of btrfs-progs.
152 Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for