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>
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 use depth-first search to print trees. (default) the nodes and
108 leaves are intermixed in the output
109 --bfs
111 use breadth-first search to print trees. the nodes are printed
112 before all leaves
113 -t <tree_id>
115 print only the tree with the specified ID, where the ID can be
116 numerical or common name in a flexible human readable form
117 The tree id name recognition rules:
119 · case does not matter
121 · the C source definition, eg. BTRFS_ROOT_TREE_OBJECTID
123 · short forms without BTRFS_ prefix, without _TREE and
125 _OBJECTID suffix, eg. ROOT_TREE, ROOT
126 · convenience aliases, eg. DEVICE for the DEV tree, CHECKSUM
128 for CSUM
129 · unrecognized ID is an error
131 inode-resolve [-v] <ino> <path>
133 (needs root privileges)
134 resolve paths to all files with given inode number ino in a given
136 subvolume at path, ie. all hardlinks
137 Options
139 -v
141 verbose mode, print count of returned paths and ioctl() return
142 value
143 logical-resolve [-Pv] [-s <bufsize>] <logical> <path>
145 (needs root privileges)
146 resolve paths to all files at given logical address in the linear
148 filesystem space
149 Options
151 -P
153 skip the path resolving and print the inodes instead
154 -v
156 verbose mode, print count of returned paths and all ioctl()
157 return values
158 -s <bufsize>
160 set internal buffer for storing the file names to bufsize,
161 default is 4096, maximum 64k
162 min-dev-size [options] <path>
164 (needs root privileges)
165 return the minimum size the device can be shrunk to, without
167 performing any resize operation, this may be useful before
168 executing the actual resize operation
169 Options
171 --id <id>
173 specify the device id to query, default is 1 if this option is
174 not used
175 rootid <path>
177 for a given file or directory, return the containing tree root id,
178 but for a subvolume itself return its own tree id (ie. subvol id)
179 Note
181 The result is undefined for the so-called empty subvolumes
182 (identified by inode number 2), but such a subvolume does not
183 contain any files anyway
184 subvolid-resolve <subvolid> <path>
186 (needs root privileges)
187 resolve the absolute path of the subvolume id subvolid
189 tree-stats [options] <device>
191 (needs root privileges)
192 Print sizes and statistics of trees.
194 Options
196 -b
198 Print raw numbers in bytes.
199
201 btrfs inspect-internal returns a zero exit status if it succeeds. Non
202 zero is returned in case of failure.
203
205 btrfs is part of btrfs-progs. Please refer to the btrfs wiki
206 http://btrfs.wiki.kernel.org for further details.
207
209 mkfs.btrfs(8)
210Btrfs v5.1 05/17/2019 BTRFS-INSPECT-INTE(8)