1BTRFS-INSPECT-INTE(8) Btrfs Manual BTRFS-INSPECT-INTE(8)
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6 btrfs-inspect-internal - query various internal information
7
9 btrfs inspect-internal <subcommand> <args>
10
12 This command group provides an interface to query internal information.
13 The functionality ranges from a simple UI to an ioctl or a more complex
14 query that assembles the result from several internal structures. The
15 latter usually requires calls to privileged ioctls.
16
18 dump-super [options] <device> [device...]
19 (replaces the standalone tool btrfs-show-super)
20 Show btrfs superblock information stored on given devices in
22 textual form. By default the first superblock is printed, more
23 details about all copies or additional backup data can be printed.
24 Besides verification of the filesystem signature, there are no
26 other sanity checks. The superblock checksum status is reported,
27 the device item and filesystem UUIDs are checked and reported.
28 Note
30 the meaning of option -s has changed in version 4.8 to be
31 consistent with other tools to specify superblock copy rather
32 the offset. The old way still works, but prints a warning.
33 Please update your scripts to use --bytenr instead. The option
34 -i has been deprecated.
35 Options
36 -f|--full
38 print full superblock information, including the system chunk
39 array and backup roots
40 -a|--all
42 print information about all present superblock copies (cannot
43 be used together with -s option)
44 -i <super>
46 (deprecated since 4.8, same behaviour as --super)
47 --bytenr <bytenr>
49 specify offset to a superblock in a non-standard location at
50 bytenr, useful for debugging (disables the -f option)
51 If there are multiple options specified, only the last one
53 applies.
54 -F|--force
56 attempt to print the superblock even if a valid BTRFS signature
57 is not found; the result may be completely wrong if the data
58 does not resemble a superblock
59 -s|--super <bytenr>
61 (see compatibility note above)
62 specify which mirror to print, valid values are 0, 1 and 2 and
64 the superblock must be present on the device with a valid
65 signature, can be used together with --force
66 dump-tree [options] <device> [device...]
68 (replaces the standalone tool btrfs-debug-tree)
69 Dump tree structures from a given device in textual form, expand
71 keys to human readable equivalents where possible. This is useful
72 for analyzing filesystem state or inconsistencies and has a
73 positive educational effect on understanding the internal
74 filesystem structure.
75 Note
77 contains file names, consider that if you’re asked to send the
78 dump for analysis. Does not contain file data.
79 Options
80 -e|--extents
82 print only extent-related information: extent and device trees
83 -d|--device
85 print only device-related information: tree root, chunk and
86 device trees
87 -r|--roots
89 print only short root node information, ie. the root tree keys
90 -R|--backups
92 same as --roots plus print backup root info, ie. the backup
93 root keys and the respective tree root block offset
94 -u|--uuid
96 print only the uuid tree information, empty output if the tree
97 does not exist
98 -b <block_num>
100 print info of the specified block only, can be specified
101 multiple times
102 --follow
104 use with -b, print all children tree blocks of <block_num>
105 --dfs
107 (default up to 5.2)
108 use depth-first search to print trees, the nodes and leaves are
110 intermixed in the output --bfs:::: (default since 5.3)
111 use breadth-first search to print trees, the nodes are printed
113 before all leaves --noscan:::: do not automatically scan the
114 system for other devices from the same filesystem, only use the
115 devices provided as the arguments -t <tree_id>:::: print only
116 the tree with the specified ID, where the ID can be numerical
117 or common name in a flexible human readable form
118 The tree id name recognition rules:
120 · case does not matter
122 · the C source definition, eg. BTRFS_ROOT_TREE_OBJECTID
124 · short forms without BTRFS_ prefix, without _TREE and
126 _OBJECTID suffix, eg. ROOT_TREE, ROOT
127 · convenience aliases, eg. DEVICE for the DEV tree, CHECKSUM
129 for CSUM
130 · unrecognized ID is an error
132 inode-resolve [-v] <ino> <path>
134 (needs root privileges)
135 resolve paths to all files with given inode number ino in a given
137 subvolume at path, ie. all hardlinks
138 Options
140 -v
142 verbose mode, print count of returned paths and ioctl() return
143 value
144 logical-resolve [-Pv] [-s <bufsize>] <logical> <path>
146 (needs root privileges)
147 resolve paths to all files at given logical address in the linear
149 filesystem space
150 Options
152 -P
154 skip the path resolving and print the inodes instead
155 -v
157 verbose mode, print count of returned paths and all ioctl()
158 return values
159 -s <bufsize>
161 set internal buffer for storing the file names to bufsize,
162 default is 4096, maximum 64k
163 min-dev-size [options] <path>
165 (needs root privileges)
166 return the minimum size the device can be shrunk to, without
168 performing any resize operation, this may be useful before
169 executing the actual resize operation
170 Options
172 --id <id>
174 specify the device id to query, default is 1 if this option is
175 not used
176 rootid <path>
178 for a given file or directory, return the containing tree root id,
179 but for a subvolume itself return its own tree id (ie. subvol id)
180 Note
182 The result is undefined for the so-called empty subvolumes
183 (identified by inode number 2), but such a subvolume does not
184 contain any files anyway
185 subvolid-resolve <subvolid> <path>
187 (needs root privileges)
188 resolve the absolute path of the subvolume id subvolid
190 tree-stats [options] <device>
192 (needs root privileges)
193 Print sizes and statistics of trees.
195 Options
197 -b
199 Print raw numbers in bytes.
200
202 btrfs inspect-internal returns a zero exit status if it succeeds. Non
203 zero is returned in case of failure.
204
206 btrfs is part of btrfs-progs. Please refer to the btrfs wiki
207 http://btrfs.wiki.kernel.org for further details.
208
210 mkfs.btrfs(8)
211Btrfs v5.4 12/03/2019 BTRFS-INSPECT-INTE(8)