user/sven/linux.git/include/uapi/linux/btrfs.h, branch v5.4.180

btrfs: clarify btrfs_ioctl_get_dev_stats padding

2019-09-09T12:59:05Z

In commit c11d2c236cc26 ("Btrfs: add ioctl to get and reset the device stats") the get_dev_stats ioctl was added. Shortly thereafter, in commit b27f7c0c150f7 ("btrfs: join DEV_STATS ioctls to one") , the flags field was added. However, the calculation for unused padding space was not updated, which also invalidated the comment. Clarify what happened to reduce confusion and wasted time for anyone implementing this. Signed-off-by: Hans van Kranenburg Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: use common vfs LABEL ioctl definitions

2019-09-09T12:58:59Z

I lifted the btrfs label get/set ioctls to the vfs some time ago, but never followed up to use those common definitions directly in btrfs. This patch does that. Signed-off-by: Eric Sandeen Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: introduce new ioctl to unregister a btrfs device

2019-02-25T13:13:30Z

Support for a new command that can be used eg. as a command $ btrfs device scan --forget [dev]' (the final name may change though) to undo the effects of 'btrfs device scan [dev]'. For this purpose this patch proposes to use ioctl #5 as it was empty and is next to the SCAN ioctl. The new ioctl BTRFS_IOC_FORGET_DEV works only on the control device (/dev/btrfs-control) to unregister one or all devices, devices that are not mounted. The argument is struct btrfs_ioctl_vol_args, ::name specifies the device path. To unregister all device, the path is an empty string. Again, the devices are removed only if they aren't part of a mounte filesystem. This new ioctl provides: - release of unwanted btrfs_fs_devices and btrfs_devices structures from memory if the device is not going to be mounted - ability to mount filesystem in degraded mode, when one devices is corrupted like in split brain raid1 - running test cases which would require reloading the kernel module but this is not possible eg. due to mounted filesystem or built-in Signed-off-by: Anand Jain Reviewed-by: David Sterba [ update changelog ] Signed-off-by: David Sterba

btrfs: Introduce support for FSID change without metadata rewrite

2018-12-17T13:51:37Z

This field is going to be used when the user wants to change the UUID of the filesystem without having to rewrite all metadata blocks. This field adds another level of indirection such that when the FSID is changed what really happens is the current UUID (the one with which the fs was created) is copied to the 'metadata_uuid' field in the superblock as well as a new incompat flag is set METADATA_UUID. When the kernel detects this flag is set it knows that the superblock in fact has 2 UUIDs: 1. Is the UUID which is user-visible, currently known as FSID. 2. Metadata UUID - this is the UUID which is stamped into all on-disk datastructures belonging to this file system. When the new incompat flag is present device scanning checks whether both fsid/metadata_uuid of the scanned device match any of the registered filesystems. When the flag is not set then both UUIDs are equal and only the FSID is retained on disk, metadata_uuid is set only in-memory during mount. Additionally a new metadata_uuid field is also added to the fs_info struct. It's initialised either with the FSID in case METADATA_UUID incompat flag is not set or with the metdata_uuid of the superblock otherwise. This commit introduces the new fields as well as the new incompat flag and switches all users of the fsid to the new logic. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba [ minor updates in comments ] Signed-off-by: David Sterba

btrfs: Add unprivileged version of ino_lookup ioctl

2018-05-31T09:35:24Z

Add unprivileged version of ino_lookup ioctl BTRFS_IOC_INO_LOOKUP_USER to allow normal users to call "btrfs subvolume list/show" etc. in combination with BTRFS_IOC_GET_SUBVOL_INFO/BTRFS_IOC_GET_SUBVOL_ROOTREF. This can be used like BTRFS_IOC_INO_LOOKUP but the argument is different. This is because it always searches the fs/file tree correspoinding to the fd with which this ioctl is called and also returns the name of bottom subvolume. The main differences from original ino_lookup ioctl are: 1. Read + Exec permission will be checked using inode_permission() during path construction. -EACCES will be returned in case of failure. 2. Path construction will be stopped at the inode number which corresponds to the fd with which this ioctl is called. If constructed path does not exist under fd's inode, -EACCES will be returned. 3. The name of bottom subvolume is also searched and filled. Note that the maximum length of path is shorter 256 (BTRFS_VOL_NAME_MAX+1) bytes than ino_lookup ioctl because of space of subvolume's name. Reviewed-by: Gu Jinxiang Reviewed-by: Qu Wenruo Tested-by: Gu Jinxiang Signed-off-by: Tomohiro Misono [ style fixes ] Signed-off-by: David Sterba

btrfs: Add unprivileged ioctl which returns subvolume's ROOT_REF

2018-05-31T09:35:23Z

Add unprivileged ioctl BTRFS_IOC_GET_SUBVOL_ROOTREF which returns ROOT_REF information of the subvolume containing this inode except the subvolume name (this is because to prevent potential name leak). The subvolume name will be gained by user version of ino_lookup ioctl (BTRFS_IOC_INO_LOOKUP_USER) which also performs permission check. The min id of root ref's subvolume to be searched is specified by @min_id in struct btrfs_ioctl_get_subvol_rootref_args. After the search ends, @min_id is set to the last searched root ref's subvolid + 1. Also, if there are more root refs than BTRFS_MAX_ROOTREF_BUFFER_NUM, -EOVERFLOW is returned. Therefore the caller can just call this ioctl again without changing the argument to continue search. Reviewed-by: Qu Wenruo Reviewed-by: Gu Jinxiang Tested-by: Gu Jinxiang Signed-off-by: Tomohiro Misono [ style fixes and struct item renames ] Signed-off-by: David Sterba

btrfs: Add unprivileged ioctl which returns subvolume information

2018-05-31T09:35:23Z

Add new unprivileged ioctl BTRFS_IOC_GET_SUBVOL_INFO which returns the information of subvolume containing this inode. (i.e. returns the information in ROOT_ITEM and ROOT_BACKREF.) Reviewed-by: Gu Jinxiang Tested-by: Gu Jinxiang Signed-off-by: Tomohiro Misono [ minor style fixes, update struct comments ] Signed-off-by: David Sterba

btrfs: put btrfs_ioctl_vol_args_v2 related defines together

2018-01-22T15:08:16Z

Just a code spatial rearrangement, no functional change. Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge branch 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2017-11-14T21:35:29Z

Pull btrfs updates from David Sterba: "There are some new user features and the usual load of invisible enhancements or cleanups. New features: - extend mount options to specify zlib compression level, -o compress=zlib:9 - v2 of ioctl "extent to inode mapping", addressing a usecase where we want to retrieve more but inaccurate results and do the postprocessing in userspace, aiding defragmentation or deduplication tools - populate compression heuristics logic, do data sampling and try to guess compressibility by: looking for repeated patterns, counting unique byte values and distribution, calculating Shannon entropy; this will need more benchmarking and possibly fine tuning, but the base should be good enough - enable indexing for btrfs as lower filesystem in overlayfs - speedup page cache readahead during send on large files Internal enhancements: - more sanity checks of b-tree items when reading them from disk - more EINVAL/EUCLEAN fixups, missing BLK_STS_* conversion, other errno or error handling fixes - remove some homegrown IO-related logic, that's been obsoleted by core block layer changes (batching, plug/unplug, own counters) - add ref-verify, optional debugging feature to verify extent reference accounting - simplify code handling outstanding extents, make it more clear where and how the accounting is done - make delalloc reservations per-inode, simplify the code and make the logic more straightforward - extensive cleanup of delayed refs code Notable fixes: - fix send ioctl on 32bit with 64bit kernel" * 'for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (102 commits) btrfs: Fix bug for misused dev_t when lookup in dev state hash table. Btrfs: heuristic: add Shannon entropy calculation Btrfs: heuristic: add byte core set calculation Btrfs: heuristic: add byte set calculation Btrfs: heuristic: add detection of repeated data patterns Btrfs: heuristic: implement sampling logic Btrfs: heuristic: add bucket and sample counters and other defines Btrfs: compression: separate heuristic/compression workspaces btrfs: move btrfs_truncate_block out of trans handle btrfs: don't call btrfs_start_delalloc_roots in flushoncommit btrfs: track refs in a rb_tree instead of a list btrfs: add a comp_refs() helper btrfs: switch args for comp_*_refs btrfs: make the delalloc block rsv per inode btrfs: add tracepoints for outstanding extents mods Btrfs: rework outstanding_extents btrfs: increase output size for LOGICAL_INO_V2 ioctl btrfs: add a flags argument to LOGICAL_INO and call it LOGICAL_INO_V2 btrfs: add a flag to iterate_inodes_from_logical to find all extent refs for uncompressed extents btrfs: send: remove unused code ...

License cleanup: add SPDX license identifier to uapi header files with a license

2017-11-02T10:20:11Z

Many user space API headers have licensing information, which is either incomplete, badly formatted or just a shorthand for referring to the license under which the file is supposed to be. This makes it hard for compliance tools to determine the correct license. Update these files with an SPDX license identifier. The identifier was chosen based on the license information in the file. GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license identifier with the added 'WITH Linux-syscall-note' exception, which is the officially assigned exception identifier for the kernel syscall exception: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". This exception makes it possible to include GPL headers into non GPL code, without confusing license compliance tools. Headers which have either explicit dual licensing or are just licensed under a non GPL license are updated with the corresponding SPDX identifier and the GPLv2 with syscall exception identifier. The format is: ((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE) SPDX license identifiers are a legally binding shorthand, which can be used instead of the full boiler plate text. The update does not remove existing license information as this has to be done on a case by case basis and the copyright holders might have to be consulted. This will happen in a separate step. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. See the previous patch in this series for the methodology of how this patch was researched. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman