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diff --git a/Documentation/btrfs-inspect-internal.asciidoc b/Documentation/btrfs-inspect-internal.asciidoc new file mode 100644 index 00000000..74f6dea8 --- /dev/null +++ b/Documentation/btrfs-inspect-internal.asciidoc @@ -0,0 +1,162 @@ +btrfs-inspect-internal(8) +========================= + +NAME +---- +btrfs-inspect-internal - query various internal information + +SYNOPSIS +-------- +*btrfs inspect-internal* <subcommand> <args> + +DESCRIPTION +----------- + +This command group provides an interface to query internal information. The +functionality ranges from a simple UI to an ioctl or a more complex query that +assembles the result from several internal structures. The latter usually +requires calls to privileged ioctls. + +SUBCOMMAND +---------- +*dump-super* [options] <device> [device...]:: +(replaces the standalone tool *btrfs-show-super*) ++ +Show btrfs superblock information stored on given devices in textual form. +By default the first superblock is printed, more details about all copies or +additional backup data can be printed. ++ +Besides verifictaion of the filesystem signature, there are no other sanity +checks. The superblock checksum status is reported, the device item and +filesystem UUIDs are checked and reported. ++ +`Options` ++ +-f|--full:::: +print full superblock information, including the system chunk array and backup roots +-a|--all:::: +print information about all present superblock copies (cannot be used together with '-i' option) +-i <super_mirror>:::: +specify which mirror to print, valid values are 0, 1 and 2 and the superblock must be present on the device ++ +If there are multiple options specified, only the last one is applies. ++ +-F|--force:::: +attempt to print the superblock even if thre's no valid BTRFS signature found ++ +The result may be completely wrong if the data do not resemble a superblock. ++ +-s <bytenr>:::: +specify offset to a superblock in a non-standard location at 'bytenr', useful +for debugging (disables the '-f' option) + +*dump-tree* [options] <device>:: +(replaces the standalone tool *btrfs-debug-tree*) ++ +Dump tree structures from a given device in textual form, expand keys to human +readable equivalents where possible. +This is useful for analyzing filesystem state or inconsistencies and has +a positive educational effect on understanding the internal filesystem structure. ++ +NOTE: contains file names, consider that if you're asked to send the dump for +analysis. Does not contain file data. ++ +`Options` ++ +-e|--extents:::: +print only extent-related information: extent and device trees +-d|--device:::: +print only device-related information: tree root, chunk and device trees +-r|--roots:::: +print only short root node information, ie. the root tree keys +-R|--backups:::: +same as --roots plus print backup root info, ie. the backup root keys and +the respective tree root block offset +-u|--uuid:::: +print only the uuid tree information, empty output if the tree does not exist +-b <block_num>:::: +print info of the specified block only +-t <tree_id>:::: +print only the tree with the specified ID, where the ID can be numerical or +common name in a flexible human readable form ++ +The tree id name recognition rules: +[options="compact"] +* case does not matter +* the C source definition, eg. BTRFS_ROOT_TREE_OBJECTID +* short forms without BTRFS_ prefix, without _TREE and _OBJECTID suffix, eg. ROOT_TREE, ROOT +* convenience aliases, eg. DEVICE for the DEV tree, CHECKSUM for CSUM +* unrecognized ID is an error + +*inode-resolve* [-v] <ino> <path>:: +(needs root privileges) ++ +resolve paths to all files with given inode number 'ino' in a given subvolume +at 'path', ie. all hardlinks ++ +`Options` ++ +-v:::: +verbose mode, print count of returned paths and ioctl() return value + +*logical-resolve* [-Pv] [-s <bufsize>] <logical> <path>:: +(needs root privileges) ++ +resolve paths to all files at given 'logical' address in the linear filesystem space ++ +`Options` ++ +-P:::: +skip the path resolving and print the inodes instead +-v:::: +verbose mode, print count of returned paths and all ioctl() return values +-s <bufsize>:::: +set internal buffer for storing the file names to 'bufsize', default is 4096, maximum 64k + +*min-dev-size* [options] <path>:: +(needs root privileges) ++ +return the minimum size the device can be shrunk to, without performing any +resize operation, this may be useful before executing the actual resize operation ++ +`Options` ++ +--id <id>:::: +specify the device 'id' to query, default is 1 if this option is not used + +*rootid* <path>:: +for a given file or directory, return the containing tree root id, for a +subvolume itself return it's own tree id (ie. subvol id) ++ +NOTE: The result is undefined for the so-called empty subvolumes (identified by +inode number 2), but such subvolume does not contain any files anyway + +*subvolid-resolve* <subvolid> <path>:: +(needs root privileges) ++ +resolve the absolute path of a the subvolume id 'subvolid' + +*tree-stats* [options] <device>:: +(needs root privileges) ++ +Print sizes and statistics of trees. ++ +`Options` ++ +-b:::: +Print raw numbers in bytes. + +EXIT STATUS +----------- +*btrfs inspect-internal* returns a zero exit status if it succeeds. Non zero is +returned in case of failure. + +AVAILABILITY +------------ +*btrfs* is part of btrfs-progs. +Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for +further details. + +SEE ALSO +-------- +`mkfs.btrfs`(8) |