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path: root/fs/btrfs/ioctl.c
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2018-05-28btrfs: rename btrfs_flags_to_ioctl to reflect which flags it touchesDavid Sterba
Converts btrfs_inode::flags to the FS_*_FL flags. Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: rename check_flags to reflect which flags it touchesDavid Sterba
The FS_*_FL flags cannot be easily identified by a prefix but we still need to recognize them so the 'fsflags' should be closer to the naming scheme but again the 'fs' part sounds like it's a filesystem flag. I don't have a better idea for now. Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: rename btrfs_mask_flags to reflect which flags it touchesDavid Sterba
The FS_*_FL flags cannot be easily identified by a variable name prefix but we still need to recognize them so the 'fsflags' should be closer to the naming scheme but again the 'fs' part sounds like it's a filesystem flag. I don't have a better idea for now. Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: rename btrfs_update_iflags to reflect which flags it touchesDavid Sterba
The btrfs inode flag flavour is now simply called 'inode flags' and the vfs inode are i_flags. Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: remove redundant btrfs_balance_control::fs_infoDavid Sterba
The fs_info is always available from the context so we don't need to store it in the structure. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: Remove delayed_iput parameter from btrfs_start_delalloc_inodesNikolay Borisov
It's always set to 0, so just remove it and collapse the constant value to the only function we are passing it. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: Remove delayed_iput parameter of btrfs_start_delalloc_rootsNikolay Borisov
This parameter was introduced alongside the function in eb73c1b7cea7 ("Btrfs: introduce per-subvolume delalloc inode list") to avoid deadlocks since this function was used in the transaction commit path. However, commit 8d875f95da43 ("btrfs: disable strict file flushes for renames and truncates") removed that usage, rendering the parameter obsolete. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: drop lock parameter from update_ioctl_balance_args and renameDavid Sterba
The parameter controls locking of the stats part but we can lock it unconditionally, as this only happens once when balance starts. This is not performance critical. Add the prefix for an exported function. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: track running balance in a simpler wayDavid Sterba
Currently fs_info::balance_running is 0 or 1 and does not use the semantics of atomics. The pause and cancel check for 0, that can happen only after __btrfs_balance exits for whatever reason. Parallel calls to balance ioctl may enter btrfs_ioctl_balance multiple times but will block on the balance_mutex that protects the fs_info::flags bit. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: kill btrfs_fs_info::volume_mutexDavid Sterba
Mutual exclusion of device add/rm and balance was done by the volume mutex up to version 3.7. The commit 5ac00addc7ac091109 ("Btrfs: disallow mutually exclusive admin operations from user mode") added a bit that essentially tracked the same information. The status bit has an advantage over a mutex that it can be set without restrictions of function context, so it started to be used in the mount-time resuming of balance or device replace. But we don't really need to track the same information in two ways. 1) After the previous cleanups, the main ioctl handlers for add/del/resize copy the EXCL_OP bit next to the volume mutex, here it's clearly safe. 2) Resuming balance during mount or after rw remount will set only the EXCL_OP bit and the volume_mutex is held in the kernel thread that calls btrfs_balance. 3) Resuming device replace during mount or after rw remount is done after balance and is excluded by the EXCL_OP bit. It does not take the volume_mutex at all and completely relies on the EXCL_OP bit. 4) The resuming of balance and dev-replace cannot hapen at the same time as the ioctls cannot be started in parallel. Nevertheless, a crafted image could trigger that and a warning is printed. 5) Balance is normally excluded by EXCL_OP and also uses own mutex to protect against concurrent access to its status data. There's some trickery to maintain the right lock nesting in case we need to reexamine the status in btrfs_ioctl_balance. The volume_mutex is removed and the unlock/lock sequence is left in place as we might expect other waiters to proceed. 6) Similar to 5, the unlock/lock sequence is kept in btrfs_cancel_balance to allow waiters to continue. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: cleanup helpers that reset balance stateDavid Sterba
The function __cancel_balance name is confusing with the cancel operation of balance and it really resets the state of balance back to zero. The unset_balance_control helper is called only from one place and simple enough to be inlined. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: move clearing of EXCL_OP out of __cancel_balanceDavid Sterba
Make the clearning visible in the callers so we can pair it with the test_and_set part. Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: move volume_mutex to callers of btrfs_rm_deviceDavid Sterba
Move locking and unlocking next to the BTRFS_FS_EXCL_OP bit manipulation so it's obvious that the two happen at the same time. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: Factor out the main deletion process from btrfs_ioctl_snap_destroy()Misono Tomohiro
Factor out the second half of btrfs_ioctl_snap_destroy() as btrfs_delete_subvolume(), which performs some subvolume specific checks before deletion: 1. send is not in progress 2. the subvolume is not the default subvolume 3. the subvolume does not contain other subvolumes and actual deletion process. btrfs_delete_subvolume() requires inode_lock for both @dir and inode of @dentry. The remaining part of btrfs_ioctl_snap_destroy() is mainly permission checks. Note that call of d_delete() is not included in btrfs_delete_subvolume() as this function will also be used by btrfs_rmdir() to delete an empty subvolume and in that case d_delete() is called in VFS layer. As a result, btrfs_unlink_subvol() and may_destroy_subvol() become static functions. No functional changes. Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor comment updates ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: Move may_destroy_subvol() from ioctl.c to inode.cMisono Tomohiro
This is a preparation work to refactor btrfs_ioctl_snap_destroy() and to allow rmdir(2) to delete an empty subvolume. Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor update of the function comment ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: rename btrfs_get_block_group_info and make it staticSu Yue
The function btrfs_get_block_group_info() was introduced by the commit 5af3e8cce8b7 ("Btrfs: make filesystem read-only when submitting barrier fails") which used it in disk-io.c. However, the function is only called in ioctl.c now. Its parameter type btrfs_ioctl_space_info* is only for ioctl. So, make it static and rename it to be original name get_block_group_info. No functional change. Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-15Merge tag 'for-4.17-part2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull more btrfs updates from David Sterba: "We have queued a few more fixes (error handling, log replay, softlockup) and the rest is SPDX updates that touche almost all files so the diffstat is long" * tag 'for-4.17-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: Only check first key for committed tree blocks btrfs: add SPDX header to Kconfig btrfs: replace GPL boilerplate by SPDX -- sources btrfs: replace GPL boilerplate by SPDX -- headers Btrfs: fix loss of prealloc extents past i_size after fsync log replay Btrfs: clean up resources during umount after trans is aborted btrfs: Fix possible softlock on single core machines Btrfs: bail out on error during replay_dir_deletes Btrfs: fix NULL pointer dereference in log_dir_items
2018-04-12btrfs: replace GPL boilerplate by SPDX -- sourcesDavid Sterba
Remove GPL boilerplate text (long, short, one-line) and keep the rest, ie. personal, company or original source copyright statements. Add the SPDX header. Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-04Merge tag 'for-4.17-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "There are a several user visible changes, the rest is mostly invisible and continues to clean up the whole code base. User visible changes: - new mount option nossd_spread (pair for ssd_spread) - mount option subvolid will detect junk after the number and fail the mount - add message after cancelled device replace - direct module dependency on libcrc32, removed own crc wrappers - removed user space transaction ioctls - use lighter locking when reading /proc/self/mounts, RCU instead of mutex to avoid unnecessary contention Enhancements: - skip writeback of last page when truncating file to same size - send: do not issue unnecessary truncate operations - mount option token specifiers: use %u for unsigned values, more validation - selftests: more tree block validations qgroups: - preparatory work for splitting reservation types for data and metadata, this should allow for more accurate tracking and fix some issues with underflows or do further enhancements - split metadata reservations for started and joined transaction so they do not get mixed up and are accounted correctly at commit time - with the above, it's possible to revert patch that potentially deadlocks when trying to make more space by explicitly committing when the quota limit is hit - fix root item corruption when multiple same source snapshots are created with quota enabled RAID56: - make sure target is identical to source when raid56 rebuild fails after dev-replace - faster rebuild during scrub, batch by stripes and not block-by-block - make more use of cached data when rebuilding from a missing device Fixes: - null pointer deref when device replace target is missing - fix fsync after hole punching when using no-holes feature - fix lockdep splat when allocating percpu data with wrong GFP flags Cleanups, refactoring, core changes: - drop redunant parameters from various functions - kill and opencode trivial helpers - __cold/__exit function annotations - dead code removal - continued audit and documentation of memory barriers - error handling: handle removal from uuid tree - error handling: remove handling of impossible condtitons - more debugging or error messages - updated tracepoints - one VLA use removal (and one still left)" * tag 'for-4.17-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (164 commits) btrfs: lift errors from add_extent_changeset to the callers Btrfs: print error messages when failing to read trees btrfs: user proper type for btrfs_mask_flags flags btrfs: split dev-replace locking helpers for read and write btrfs: remove stale comments about fs_mutex btrfs: use RCU in btrfs_show_devname for device list traversal btrfs: update barrier in should_cow_block btrfs: use lockdep_assert_held for mutexes btrfs: use lockdep_assert_held for spinlocks btrfs: Validate child tree block's level and first key btrfs: tests/qgroup: Fix wrong tree backref level Btrfs: fix copy_items() return value when logging an inode Btrfs: fix fsync after hole punching when using no-holes feature btrfs: use helper to set ulist aux from a qgroup Revert "btrfs: qgroups: Retry after commit on getting EDQUOT" btrfs: qgroup: Update trace events for metadata reservation btrfs: qgroup: Use root::qgroup_meta_rsv_* to record qgroup meta reserved space btrfs: delayed-inode: Use new qgroup meta rsv for delayed inode and item btrfs: qgroup: Use separate meta reservation type for delalloc btrfs: qgroup: Introduce function to convert META_PREALLOC into META_PERTRANS ...
2018-03-31btrfs: user proper type for btrfs_mask_flags flagsDavid Sterba
All users pass a local unsigned int and not the __uXX types that are supposed to be used for userspace interfaces. Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31btrfs: qgroup: Use separate meta reservation type for delallocQu Wenruo
Before this patch, btrfs qgroup is mixing per-transcation meta rsv with preallocated meta rsv, making it quite easy to underflow qgroup meta reservation. Since we have the new qgroup meta rsv types, apply it to delalloc reservation. Now for delalloc, most of its reserved space will use META_PREALLOC qgroup rsv type. And for callers reducing outstanding extent like btrfs_finish_ordered_io(), they will convert corresponding META_PREALLOC reservation to META_PERTRANS. This is mainly due to the fact that current qgroup numbers will only be updated in btrfs_commit_transaction(), that's to say if we don't keep such placeholder reservation, we can exceed qgroup limitation. And for callers freeing outstanding extent in error handler, we will just free META_PREALLOC bytes. This behavior makes callers of btrfs_qgroup_release_meta() or btrfs_qgroup_convert_meta() to be aware of which type they are. So in this patch, btrfs_delalloc_release_metadata() and its callers get an extra parameter to info qgroup to do correct meta convert/release. The good news is, even we use the wrong type (convert or free), it won't cause obvious bug, as prealloc type is always in good shape, and the type only affects how per-trans meta is increased or not. So the worst case will be at most metadata limitation can be sometimes exceeded (no convert at all) or metadata limitation is reached too soon (no free at all). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31btrfs: Handle error from btrfs_uuid_tree_rem call in ↵Nikolay Borisov
_btrfs_ioctl_set_received_subvol As with every function which deals with modifying the btree btrfs_uuid_tree_rem can fail for any number of reasons (ie. EIO/ENOMEM). Handle return error value from this function gracefully by aborting the transaction. Fixes: dd5f9615fc5c ("Btrfs: maintain subvolume items in the UUID tree") Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31btrfs: Remove userspace transaction ioctlsNikolay Borisov
Commit 3558d4f88ec8 ("btrfs: Deprecate userspace transaction ioctls") marked the beginning of the end of userspace transaction. This commit finishes the job! There are no known users and ceph does not use the ioctl anymore. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Acked-by: Sage Weil <sage@redhat.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31btrfs: add define for oldest generationAnand Jain
Some functions can filter metadata by the generation. Add a define that will annotate such arguments. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-26btrfs: rename __btrfs_dev_replace_cancel()Anand Jain
Remove __ which is for the special functions. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-26btrfs: open code btrfs_dev_replace_cancel()Anand Jain
btrfs_dev_replace_cancel() calls __btrfs_dev_replace_cancel() for the actual cancel so just open code it. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-20sched/wait, fs/btrfs: Convert wait_on_atomic_t() usage to the new ↵Peter Zijlstra
wait_var_event() API The old wait_on_atomic_t() is going to get removed, use the more flexible wait_var_event() API instead. No change in functionality. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: David Sterba <dsterba@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-29Merge tag 'for-4.16-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "Features or user visible changes: - fallocate: implement zero range mode - avoid losing data raid profile when deleting a device - tree item checker: more checks for directory items and xattrs Notable fixes: - raid56 recovery: don't use cached stripes, that could be potentially changed and a later RMW or recovery would lead to corruptions or failures - let raid56 try harder to rebuild damaged data, reading from all stripes if necessary - fix scrub to repair raid56 in a similar way as in the case above Other: - cleanups: device freeing, removed some call indirections, redundant bio_put/_get, unused parameters, refactorings and renames - RCU list traversal fixups - simplify mount callchain, remove recursing back when mounting a subvolume - plug for fsync, may improve bio merging on multiple devices - compression heurisic: replace heap sort with radix sort, gains some performance - add extent map selftests, buffered write vs dio" * tag 'for-4.16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (155 commits) btrfs: drop devid as device_list_add() arg btrfs: get device pointer from device_list_add() btrfs: set the total_devices in device_list_add() btrfs: move pr_info into device_list_add btrfs: make btrfs_free_stale_devices() to match the path btrfs: rename btrfs_free_stale_devices() arg to skip_dev btrfs: make btrfs_free_stale_devices() argument optional btrfs: make btrfs_free_stale_device() to iterate all stales btrfs: no need to check for btrfs_fs_devices::seeding btrfs: Use IS_ALIGNED in btrfs_truncate_block instead of opencoding it Btrfs: noinline merge_extent_mapping Btrfs: add WARN_ONCE to detect unexpected error from merge_extent_mapping Btrfs: extent map selftest: dio write vs dio read Btrfs: extent map selftest: buffered write vs dio read Btrfs: add extent map selftests Btrfs: move extent map specific code to extent_map.c Btrfs: add helper for em merge logic Btrfs: fix unexpected EEXIST from btrfs_get_extent Btrfs: fix incorrect block_len in merge_extent_mapping btrfs: Remove unused readahead spinlock ...
2018-01-29fs: new API for handling inode->i_versionJeff Layton
Add a documentation blob that explains what the i_version field is, how it is expected to work, and how it is currently implemented by various filesystems. We already have inode_inc_iversion. Add several other functions for manipulating and accessing the i_version counter. For now, the implementation is trivial and basically works the way that all of the open-coded i_version accesses work today. Future patches will convert existing users of i_version to use the new API, and then convert the backend implementation to do things more efficiently. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz>
2018-01-22btrfs: use correct string length in DEV_INFO ioctlXiongfeng Wang
gcc-8 reports: fs/btrfs/ioctl.c: In function 'btrfs_ioctl': ./include/linux/string.h:245:9: warning: '__builtin_strncpy' specified bound 1024 equals destination size [-Wstringop-truncation] We need one less byte or call strlcpy() to make it a nul-terminated string. This is done on the next line anyway, but we want to avoid the warning. Signed-off-by: Xiongfeng Wang <xiongfeng.wang@linaro.org> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: sink unlock_extent parameter gfp_flagsDavid Sterba
All callers pass either GFP_NOFS or GFP_KERNEL now, so we can sink the parameter to the function, though we lose some of the slightly better semantics of GFP_KERNEL in some places, it's worth cleaning up the callchains. Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: SETFLAGS ioctl: use helper for compression type conversionDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: cleanup device states define BTRFS_DEV_STATE_REPLACE_TGTAnand Jain
Currently device state is being managed by each individual int variable such as struct btrfs_device::is_tgtdev_for_dev_replace. Instead of that declare btrfs_device::dev_state BTRFS_DEV_STATE_MISSING and use the bit operations. Signed-off-by: Anand Jain <anand.jain@oracle.com> [ whitespace adjustments ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: cleanup device states define BTRFS_DEV_STATE_WRITEABLEAnand Jain
Currently device state is being managed by each individual int variable such as struct btrfs_device::writeable. Instead of that declare device state BTRFS_DEV_STATE_WRITEABLE and use the bit operations. Signed-off-by: Anand Jain <anand.jain@oracle.com> [ whitespace adjustments ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: sink gfp parameter to clear_extent_bitDavid Sterba
All callers use GFP_NOFS, we don't have to pass it as an argument. The built-in tests pass GFP_KERNEL, but they run only at module load time and NOFS works there as well. Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: switch to RCU for device traversal in btrfs_ioctl_fs_infoDavid Sterba
We don't need to use the mutex as we do not modify the devices nor the list itself and just read information about device counts. Move copying fsid out of the protected section, not applicable to RCU same as the rest of the retrieved information. Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: switch to RCU for device traversal in btrfs_ioctl_dev_infoDavid Sterba
We don't need to use the mutex as we do not modify the devices nor the list itself and just read some information: does not change during device lifetime: - devid - uuid - name (ie. the path) may change in parallel to the ioctl call, but can lead only to reporting inacurracy: - bytes_used - total_bytes Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22btrfs: move volume_mutex into the btrfs_rm_device()Anand Jain
A cleanup patch no functional change, we hold volume_mutex before calling btrfs_rm_device, so move it into the function itself. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-12-10Merge tag 'for-4.15-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "This contains a few fixes (error handling, quota leak, FUA vs nobarrier mount option). There's one one worth mentioning separately - an off-by-one fix that leads to overwriting first byte of an adjacent page with 0, out of bounds of the memory allocated by an ioctl. This is under a privileged part of the ioctl, can be triggerd in some subvolume layouts" * tag 'for-4.15-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: Fix possible off-by-one in btrfs_search_path_in_tree Btrfs: disable FUA if mounted with nobarrier btrfs: fix missing error return in btrfs_drop_snapshot btrfs: handle errors while updating refcounts in update_ref_for_cow btrfs: Fix quota reservation leak on preallocated files
2017-12-07btrfs: Fix possible off-by-one in btrfs_search_path_in_treeNikolay Borisov
The name char array passed to btrfs_search_path_in_tree is of size BTRFS_INO_LOOKUP_PATH_MAX (4080). So the actual accessible char indexes are in the range of [0, 4079]. Currently the code uses the define but this represents an off-by-one. Implications: Size of btrfs_ioctl_ino_lookup_args is 4096, so the new byte will be written to extra space, not some padding that could be provided by the allocator. btrfs-progs store the arguments on stack, but kernel does own copy of the ioctl buffer and the off-by-one overwrite does not affect userspace, but the ending 0 might be lost. Kernel ioctl buffer is allocated dynamically so we're overwriting somebody else's memory, and the ioctl is privileged if args.objectid is not 256. Which is in most cases, but resolving a subvolume stored in another directory will trigger that path. Before this patch the buffer was one byte larger, but then the -1 was not added. Fixes: ac8e9819d71f907 ("Btrfs: add search and inode lookup ioctls") Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ added implications ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-27Rename superblock flags (MS_xyz -> SB_xyz)Linus Torvalds
This is a pure automated search-and-replace of the internal kernel superblock flags. The s_flags are now called SB_*, with the names and the values for the moment mirroring the MS_* flags that they're equivalent to. Note how the MS_xyz flags are the ones passed to the mount system call, while the SB_xyz flags are what we then use in sb->s_flags. The script to do this was: # places to look in; re security/*: it generally should *not* be # touched (that stuff parses mount(2) arguments directly), but # there are two places where we really deal with superblock flags. FILES="drivers/mtd drivers/staging/lustre fs ipc mm \ include/linux/fs.h include/uapi/linux/bfs_fs.h \ security/apparmor/apparmorfs.c security/apparmor/include/lib.h" # the list of MS_... constants SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \ DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \ POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \ I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \ ACTIVE NOUSER" SED_PROG= for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done # we want files that contain at least one of MS_..., # with fs/namespace.c and fs/pnode.c excluded. L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c') for f in $L; do sed -i $f $SED_PROG; done Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-01Btrfs: rework outstanding_extentsJosef Bacik
Right now we do a lot of weird hoops around outstanding_extents in order to keep the extent count consistent. This is because we logically transfer the outstanding_extent count from the initial reservation through the set_delalloc_bits. This makes it pretty difficult to get a handle on how and when we need to mess with outstanding_extents. Fix this by revamping the rules of how we deal with outstanding_extents. Now instead everybody that is holding on to a delalloc extent is required to increase the outstanding extents count for itself. This means we'll have something like this btrfs_delalloc_reserve_metadata - outstanding_extents = 1 btrfs_set_extent_delalloc - outstanding_extents = 2 btrfs_release_delalloc_extents - outstanding_extents = 1 for an initial file write. Now take the append write where we extend an existing delalloc range but still under the maximum extent size btrfs_delalloc_reserve_metadata - outstanding_extents = 2 btrfs_set_extent_delalloc btrfs_set_bit_hook - outstanding_extents = 3 btrfs_merge_extent_hook - outstanding_extents = 2 btrfs_delalloc_release_extents - outstanding_extnets = 1 In order to make the ordered extent transition we of course must now make ordered extents carry their own outstanding_extent reservation, so for cow_file_range we end up with btrfs_add_ordered_extent - outstanding_extents = 2 clear_extent_bit - outstanding_extents = 1 btrfs_remove_ordered_extent - outstanding_extents = 0 This makes all manipulations of outstanding_extents much more explicit. Every successful call to btrfs_delalloc_reserve_metadata _must_ now be combined with btrfs_release_delalloc_extents, even in the error case, as that is the only function that actually modifies the outstanding_extents counter. The drawback to this is now we are much more likely to have transient cases where outstanding_extents is much larger than it actually should be. This could happen before as we manipulated the delalloc bits, but now it happens basically at every write. This may put more pressure on the ENOSPC flushing code, but I think making this code simpler is worth the cost. I have another change coming to mitigate this side-effect somewhat. I also added trace points for the counter manipulation. These were used by a bpf script I wrote to help track down leak issues. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-01btrfs: increase output size for LOGICAL_INO_V2 ioctlZygo Blaxell
Build-server workloads have hundreds of references per file after dedup. Multiply by a few snapshots and we quickly exhaust the limit of 2730 references per extent that can fit into a 64K buffer. Raise the limit to 16M to be consistent with other btrfs ioctls (e.g. TREE_SEARCH_V2, FILE_EXTENT_SAME). To minimize surprising userspace behavior, apply this change only to the LOGICAL_INO_V2 ioctl. Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-01btrfs: add a flags argument to LOGICAL_INO and call it LOGICAL_INO_V2Zygo Blaxell
Now that check_extent_in_eb()'s extent offset filter can be turned off, we need a way to do it from userspace. Add a 'flags' field to the btrfs_logical_ino_args structure to disable extent offset filtering, taking the place of one of the existing reserved[] fields. Previous versions of LOGICAL_INO neglected to check whether any of the reserved fields have non-zero values. Assigning meaning to those fields now may change the behavior of existing programs that left these fields uninitialized. The lack of a zero check also means that new programs have no way to know whether the kernel is honoring the flags field. To avoid these problems, define a new ioctl LOGICAL_INO_V2. We can use the same argument layout as LOGICAL_INO, but shorten the reserved[] array by one element and turn it into the 'flags' field. The V2 ioctl explicitly checks that reserved fields and unsupported flag bits are zero so that userspace can negotiate future feature bits as they are defined. Since the memory layouts of the two ioctls' arguments are compatible, there is no need for a separate function for logical_to_ino_v2 (contrast with tree_search_v2 vs tree_search where the layout and code are quite different). A version parameter and an 'if' statement will suffice. Now that we have a flags field in logical_ino_args, add a flag BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET to get the behavior we want, and pass it down the stack to iterate_inodes_from_logical. Motivation and background, copied from the patchset cover letter: Suppose we have a file with one extent: root@tester:~# zcat /usr/share/doc/cpio/changelog.gz > /test/a root@tester:~# sync Split the extent by overwriting it in the middle: root@tester:~# cat /dev/urandom | dd bs=4k seek=2 skip=2 count=1 conv=notrunc of=/test/a We should now have 3 extent refs to 2 extents, with one block unreachable. The extent tree looks like: root@tester:~# btrfs-debug-tree /dev/vdc -t 2 [...] item 9 key (1103101952 EXTENT_ITEM 73728) itemoff 15942 itemsize 53 extent refs 2 gen 29 flags DATA extent data backref root 5 objectid 261 offset 0 count 2 [...] item 11 key (1103175680 EXTENT_ITEM 4096) itemoff 15865 itemsize 53 extent refs 1 gen 30 flags DATA extent data backref root 5 objectid 261 offset 8192 count 1 [...] and the ref tree looks like: root@tester:~# btrfs-debug-tree /dev/vdc -t 5 [...] item 6 key (261 EXTENT_DATA 0) itemoff 15825 itemsize 53 extent data disk byte 1103101952 nr 73728 extent data offset 0 nr 8192 ram 73728 extent compression(none) item 7 key (261 EXTENT_DATA 8192) itemoff 15772 itemsize 53 extent data disk byte 1103175680 nr 4096 extent data offset 0 nr 4096 ram 4096 extent compression(none) item 8 key (261 EXTENT_DATA 12288) itemoff 15719 itemsize 53 extent data disk byte 1103101952 nr 73728 extent data offset 12288 nr 61440 ram 73728 extent compression(none) [...] There are two references to the same extent with different, non-overlapping byte offsets: [------------------72K extent at 1103101952----------------------] [--8K----------------|--4K unreachable----|--60K-----------------] ^ ^ | | [--8K ref offset 0--][--4K ref offset 0--][--60K ref offset 12K--] | v [-----4K extent-----] at 1103175680 We want to find all of the references to extent bytenr 1103101952. Without the patch (and without running btrfs-debug-tree), we have to do it with 18 LOGICAL_INO calls: root@tester:~# btrfs ins log 1103101952 -P /test/ Using LOGICAL_INO inode 261 offset 0 root 5 root@tester:~# for x in $(seq 0 17); do btrfs ins log $((1103101952 + x * 4096)) -P /test/; done 2>&1 | grep inode inode 261 offset 0 root 5 inode 261 offset 4096 root 5 <- same extent ref as offset 0 (offset 8192 returns empty set, not reachable) inode 261 offset 12288 root 5 inode 261 offset 16384 root 5 \ inode 261 offset 20480 root 5 | inode 261 offset 24576 root 5 | inode 261 offset 28672 root 5 | inode 261 offset 32768 root 5 | inode 261 offset 36864 root 5 \ inode 261 offset 40960 root 5 > all the same extent ref as offset 12288. inode 261 offset 45056 root 5 / More processing required in userspace inode 261 offset 49152 root 5 | to figure out these are all duplicates. inode 261 offset 53248 root 5 | inode 261 offset 57344 root 5 | inode 261 offset 61440 root 5 | inode 261 offset 65536 root 5 | inode 261 offset 69632 root 5 / In the worst case the extents are 128MB long, and we have to do 32768 iterations of the loop to find one 4K extent ref. With the patch, we just use one call to map all refs to the extent at once: root@tester:~# btrfs ins log 1103101952 -P /test/ Using LOGICAL_INO_V2 inode 261 offset 0 root 5 inode 261 offset 12288 root 5 The TREE_SEARCH ioctl allows userspace to retrieve the offset and extent bytenr fields easily once the root, inode and offset are known. This is sufficient information to build a complete map of the extent and all of its references. Userspace can use this information to make better choices to dedup or defrag. Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> Tested-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com> [ copy background and motivation from cover letter ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-01btrfs: add a flag to iterate_inodes_from_logical to find all extent refs for ↵Zygo Blaxell
uncompressed extents The LOGICAL_INO ioctl provides a backward mapping from extent bytenr and offset (encoded as a single logical address) to a list of extent refs. LOGICAL_INO complements TREE_SEARCH, which provides the forward mapping (extent ref -> extent bytenr and offset, or logical address). These are useful capabilities for programs that manipulate extents and extent references from userspace (e.g. dedup and defrag utilities). When the extents are uncompressed (and not encrypted and not other), check_extent_in_eb performs filtering of the extent refs to remove any extent refs which do not contain the same extent offset as the 'logical' parameter's extent offset. This prevents LOGICAL_INO from returning references to more than a single block. To find the set of extent references to an uncompressed extent from [a, b), userspace has to run a loop like this pseudocode: for (i = a; i < b; ++i) extent_ref_set += LOGICAL_INO(i); At each iteration of the loop (up to 32768 iterations for a 128M extent), data we are interested in is collected in the kernel, then deleted by the filter in check_extent_in_eb. When the extents are compressed (or encrypted or other), the 'logical' parameter must be an extent bytenr (the 'a' parameter in the loop). No filtering by extent offset is done (or possible?) so the result is the complete set of extent refs for the entire extent. This removes the need for the loop, since we get all the extent refs in one call. Add an 'ignore_offset' argument to iterate_inodes_from_logical, [...several levels of function call graph...], and check_extent_in_eb, so that we can disable the extent offset filtering for uncompressed extents. This flag can be set by an improved version of the LOGICAL_INO ioctl to get either behavior as desired. There is no functional change in this patch. The new flag is always false. Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: David Sterba <dsterba@suse.com> [ minor coding style fixes ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30btrfs: pass root to various extent ref mod functionsJosef Bacik
We need the actual root for the ref verifier tool to work, so change these functions to pass the root around instead. This will be used in a subsequent patch. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30btrfs: fix send ioctl on 32bit with 64bit kernelJosef Bacik
We pass in a pointer in our send arg struct, this means the struct size doesn't match with 32bit user space and 64bit kernel space. Fix this by adding a compat mode and doing the appropriate conversion. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> [ move structure to the beginning, next to receive 32bit compat ] Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30Btrfs: do not make defrag wait on async_delalloc_pagesLiu Bo
By setting compression for a defrag task, the task will start IO at the end of defrag. After the combo of filemap_flush(), we've already made sure that dirty pages have made progress via async compress thread because the second filemap_flush() will wait for page lock, which won't be unlocked until those pages have been marked as writeback and ordered extents have been queued. And this is for per-inode defrag, it's not helpful to wait on a global %async_delalloc_pages and %nr_async_submits from fs_info. Although waiting on %nr_async_submits means that all bios are submitted down to per-device schedule IO lists, it doesn't wait for their completions, thus users still need to do fsync/sync to make sure the data is on disk. While with this change, it makes sure that pages are marked with writeback bits and will be submitted asynchronously shortly, therefore, the behavior of defrag option '-c' remains unchanged. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30btrfs: Refactor transaction handling in received subvolume ioctlNikolay Borisov
If btrfs_transaction_commit fails it will proceed to call cleanup_transaction, which in turn already does btrfs_abort_transaction. So let's remove the unnecessary code duplication. Also let's be explicit about handling failure of btrfs_uuid_tree_add by calling btrfs_end_transaction. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30btrfs: Explicitly handle btrfs_update_root failureNikolay Borisov
btrfs_udpate_root can fail and it aborts the transaction, the correct way to handle an aborted transaction is to explicitly end with btrfs_end_transaction. Even now the code is correct since btrfs_commit_transaction would handle an aborted transaction but this is more of an implementation detail. So let's be explicit in handling failure in btrfs_update_root. Furthermore btrfs_commit_transaction can also fail and by ignoring it's return value we could have left the in-memory copy of the root item in an inconsistent state. So capture the error value which allows us to correctly revert the RO/RW flags in case of commit failure. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>