wireguard-linux/fs/btrfs/ioctl.c, branch jd/unified-crypt-queue

btrfs: Remove async_transid from btrfs_mksubvol/create_subvol/create_snapshot

2020-03-23T16:02:00Z

With BTRFS_SUBVOL_CREATE_ASYNC support remove it's no longer required to pass the async_transid parameter so remove it and any code using it. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: Remove transid argument from btrfs_ioctl_snap_create_transid

2020-03-23T16:02:00Z

btrfs_ioctl_snap_create_transid no longer takes a transid argument, so remove it and rename the function to __btrfs_ioctl_snap_create to reflect it's an internal, worker function. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: Remove BTRFS_SUBVOL_CREATE_ASYNC support

2020-03-23T16:02:00Z

This functionality was deprecated in kernel 5.4. Since no one has complained of the impending removal it's time we did so. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba [ add comment ] Signed-off-by: David Sterba

Btrfs: move all reflink implementation code into its own file

2020-03-23T16:01:54Z

The reflink code is quite large and has been living in ioctl.c since ever. It has grown over the years after many bug fixes and improvements, and since I'm planning on making some further improvements on it, it's time to get it better organized by moving into its own file, reflink.c (similar to what xfs does for example). This change only moves the code out of ioctl.c into the new file, it doesn't do any other change. Reviewed-by: Josef Bacik Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: switch to use new generic UUID API

2020-03-23T16:01:47Z

There are new types and helpers that are supposed to be used in new code. As a preparation to get rid of legacy types and API functions do the conversion here. Reviewed-by: Christoph Hellwig Signed-off-by: Andy Shevchenko Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: ioctl: resize: only show message if size is changed

2020-03-23T16:01:46Z

There is no point to inform the user about size change if there's none. Update the message to conform to a commonly used format where the path and devid are printed and also print old and new sizes. Reviewed-by: Johannes Thumshirn Signed-off-by: Marcos Paulo de Souza Reviewed-by: David Sterba [ enhance message ] Signed-off-by: David Sterba

btrfs: convert snapshot/nocow exlcusion to drew lock

2020-03-23T16:01:44Z

This patch removes all haphazard code implementing nocow writers exclusion from pending snapshot creation and switches to using the drew lock to ensure this invariant still holds. 'Readers' are snapshot creators from create_snapshot and 'writers' are nocow writers from buffered write path or btrfs_setsize. This locking scheme allows for multiple snapshots to happen while any nocow writers are blocked, since writes to page cache in the nocow path will make snapshots inconsistent. So for performance reasons we'd like to have the ability to run multiple concurrent snapshots and also favors readers in this case. And in case there aren't pending snapshots (which will be the majority of the cases) we rely on the percpu's writers counter to avoid cacheline contention. The main gain from using the drew lock is it's now a lot easier to reason about the guarantees of the locking scheme and whether there is some silent breakage lurking. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: add new BTRFS_IOC_SNAP_DESTROY_V2 ioctl

2020-03-23T16:01:42Z

This ioctl will be responsible for deleting a subvolume using its id. This can be used when a system has a file system mounted from a subvolume, rather than the root file system, like below: / @subvol1/ @subvol2/ @subvol_default/ If only @subvol_default is mounted, we have no path to reach @subvol1 and @subvol2, thus no way to delete them. Current subvolume delete ioctl takes a file handle point as argument, and if @subvol_default is mounted, we can't reach @subvol1 and @subvol2 from the same mount point. This patch introduces a new ioctl BTRFS_IOC_SNAP_DESTROY_V2 that takes the extended structure with flags to allow to delete subvolume using subvolid. Now, we can use this new ioctl specifying the subvolume id and refer to the same mount point. It doesn't matter which subvolume was mounted, since we can reach to the desired one using the subvolume id, and then delete it. The full path to the subvolume id is resolved internally and access is verified as if the subvolume was accessed by path. The volume args v2 structure is extended to use the existing union for subvolume id specification, that's valid in case the BTRFS_SUBVOL_SPEC_BY_ID is set. Signed-off-by: Marcos Paulo de Souza Reviewed-by: David Sterba [ update changelog ] Signed-off-by: David Sterba

btrfs: use ioctl args support mask for device delete

2020-03-23T16:01:42Z

When the device remove v2 ioctl was added, the full support mask was added to sanity check the flags. However this would allow to let the subvolume related flags to be accepted. This is not supposed to happen. Use the correct support mask, which means that now any of BTRFS_SUBVOL_CREATE_ASYNC, BTRFS_SUBVOL_RDONLY or BTRFS_SUBVOL_QGROUP_INHERIT will be rejected as ENOTSUPP. Though this is a user-visible change, specifying subvolume flags for device deletion does not make sense and there are hopefully no applications doing that. Reviewed-by: Marcos Paulo de Souza Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba

btrfs: use ioctl args support mask for subvolume create/delete

2020-03-23T16:01:42Z

Using the defined mask instead of flag enumeration in the ioctl handler is preferred. No functional changes. Reviewed-by: Marcos Paulo de Souza Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba