user/sven/linux.git/include/uapi/linux/btrfs.h, branch v5.4.269

btrfs: defrag: reject unknown flags of btrfs_ioctl_defrag_range_args

2024-02-23T07:24:52Z

commit 173431b274a9a54fc10b273b46e67f46bcf62d2e upstream. Add extra sanity check for btrfs_ioctl_defrag_range_args::flags. This is not really to enhance fuzzing tests, but as a preparation for future expansion on btrfs_ioctl_defrag_range_args. In the future we're going to add new members, allowing more fine tuning for btrfs defrag. Without the -ENONOTSUPP error, there would be no way to detect if the kernel supports those new defrag features. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Filipe Manana Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

btrfs: scrub: reject unsupported scrub flags

2023-05-17T09:35:55Z

commit 604e6681e114d05a2e384c4d1e8ef81918037ef5 upstream. Since the introduction of scrub interface, the only flag that we support is BTRFS_SCRUB_READONLY. Thus there is no sanity checks, if there are some undefined flags passed in, we just ignore them. This is problematic if we want to introduce new scrub flags, as we have no way to determine if such flags are supported. Address the problem by introducing a check for the flags, and if unsupported flags are set, return -EOPNOTSUPP to inform the user space. This check should be backported for all supported kernels before any new scrub flags are introduced. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Anand Jain Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

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