Commit Graph

208 Commits (master)

Author SHA1 Message Date
Linus Torvalds 416f99c3b1 Driver core changes for 6.19-rc1
- Arch Topology:
   - Move parse_acpi_topology() from arm64 to common code for reuse in RISC-V
 
 - CPU:
   - Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping
   - Print a newline (or 0x0A) instead of '(null)' reading
     /sys/devices/system/cpu/nohz_full when nohz_full= is not set
 
 - debugfs
   - Remove (broken) 'no-mount' mode
   - Remove redundant access mode checks in debugfs_get_tree() and
     debugfs_create_*() functions
 
 - Devres:
   - Remove unused devm_free_percpu() helper
   - Move devm_alloc_percpu() from device.h to devres.h
 
 - Firmware Loader:
   - Replace simple_strtol() with kstrtoint()
   - Do not call cancel_store() when no upload is in progress
 
 - kernfs:
   - Increase struct super_block::maxbytes to MAX_LFS_FILESIZE
   - Fix a missing unwind path in __kernfs_new_node()
 
 - Misc:
   - Increase the name size in struct auxiliary_device_id to 40 characters
   - Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to
     alloc_workqueue()
 
 - Platform:
   - Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap functions
 
 - Rust:
   - Auxiliary:
     - Unregister auxiliary device on parent device unbind
     - Move parent() to impl Device; implement device context aware parent() for
       Device<Bound>
     - Illustrate how to safely obtain a driver's device private data when
       calling from an auxiliary driver into the parant device driver
 
   - DebugFs:
     - Implement support for binary large objects
 
   - Device:
     - Let probe() return the driver's device private data as pinned initializer,
       i.e. impl PinInit<Self, Error>
     - Implement safe accessor for a driver's device private data for
       Device<Bound> (returned reference can't out-live driver binding and
       guarantees the correct private data type)
     - Implement AsBusDevice trait, to be used by class device abstractions to
       derive the bus device type of the parent device
 
   - DMA:
     - Store raw pointer of allocation as NonNull
     - Use start_ptr() and start_ptr_mut() to inherit correct mutability of self
 
   - FS:
     - Add file::Offset type alias
 
   - I2C:
     - Add abstractions for I2C device / driver infrastructure
     - Implement abstractions for manual I2C device registrations
 
   - I/O:
     - Use "kernel vertical" style for imports
     - Define ResourceSize as resource_size_t
     - Move ResourceSize to top-level I/O module
     - Add type alias for phys_addr_t
     - Implement Rust version of read_poll_timeout_atomic()
 
   - PCI:
     - Use "kernel vertical" style for imports
     - Move I/O and IRQ infrastructure to separate files
     - Add support for PCI interrupt vectors
     - Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert an
       IrqVector bound to specific pci::Device into an IrqRequest bound to the
       same pci::Device's parent Device
     - Leverage pin_init_scope() to get rid of redundant Result in IRQ methods
 
   - PinInit:
     - Add {pin_}init_scope() to execute code before creating an initializer
 
   - Platform:
     - Leverage pin_init_scope() to get rid of redundant Result in IRQ methods
 
   - Timekeeping:
     - Implement abstraction of udelay()
 
   - Uaccess:
     - Implement read_slice_partial() and read_slice_file() for UserSliceReader
     - Implement write_slice_partial() and write_slice_file() for UserSliceWriter
 
 - sysfs
   - Prepare the constification of struct attribute
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Merge tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

Pull driver core updates from Danilo Krummrich:
 "Arch Topology:
   - Move parse_acpi_topology() from arm64 to common code for reuse in
     RISC-V

  CPU:
   - Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping
   - Print a newline (or 0x0A) instead of '(null)' reading
     /sys/devices/system/cpu/nohz_full when nohz_full= is not set

  debugfs
   - Remove (broken) 'no-mount' mode
   - Remove redundant access mode checks in debugfs_get_tree() and
     debugfs_create_*() functions

  Devres:
   - Remove unused devm_free_percpu() helper
   - Move devm_alloc_percpu() from device.h to devres.h

  Firmware Loader:
   - Replace simple_strtol() with kstrtoint()
   - Do not call cancel_store() when no upload is in progress

  kernfs:
   - Increase struct super_block::maxbytes to MAX_LFS_FILESIZE
   - Fix a missing unwind path in __kernfs_new_node()

  Misc:
   - Increase the name size in struct auxiliary_device_id to 40
     characters
   - Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to
     alloc_workqueue()

  Platform:
   - Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap
     functions

  Rust:
   - Auxiliary:
      - Unregister auxiliary device on parent device unbind
      - Move parent() to impl Device; implement device context aware
        parent() for Device<Bound>
      - Illustrate how to safely obtain a driver's device private data
        when calling from an auxiliary driver into the parant device
        driver

   - DebugFs:
      - Implement support for binary large objects

   - Device:
      - Let probe() return the driver's device private data as pinned
        initializer, i.e. impl PinInit<Self, Error>
      - Implement safe accessor for a driver's device private data for
        Device<Bound> (returned reference can't out-live driver binding
        and guarantees the correct private data type)
      - Implement AsBusDevice trait, to be used by class device
        abstractions to derive the bus device type of the parent device

   - DMA:
      - Store raw pointer of allocation as NonNull
      - Use start_ptr() and start_ptr_mut() to inherit correct
        mutability of self

   - FS:
      - Add file::Offset type alias

   - I2C:
      - Add abstractions for I2C device / driver infrastructure
      - Implement abstractions for manual I2C device registrations

   - I/O:
      - Use "kernel vertical" style for imports
      - Define ResourceSize as resource_size_t
      - Move ResourceSize to top-level I/O module
      - Add type alias for phys_addr_t
      - Implement Rust version of read_poll_timeout_atomic()

   - PCI:
      - Use "kernel vertical" style for imports
      - Move I/O and IRQ infrastructure to separate files
      - Add support for PCI interrupt vectors
      - Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert
        an IrqVector bound to specific pci::Device into an IrqRequest
        bound to the same pci::Device's parent Device
      - Leverage pin_init_scope() to get rid of redundant Result in IRQ
        methods

   - PinInit:
      - Add {pin_}init_scope() to execute code before creating an
        initializer

   - Platform:
      - Leverage pin_init_scope() to get rid of redundant Result in IRQ
        methods

   - Timekeeping:
      - Implement abstraction of udelay()

   - Uaccess:
      - Implement read_slice_partial() and read_slice_file() for
        UserSliceReader
      - Implement write_slice_partial() and write_slice_file() for
        UserSliceWriter

  sysfs:
   - Prepare the constification of struct attribute"

* tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (75 commits)
  rust: pci: fix build failure when CONFIG_PCI_MSI is disabled
  debugfs: Fix default access mode config check
  debugfs: Remove broken no-mount mode
  debugfs: Remove redundant access mode checks
  driver core: Check drivers_autoprobe for all added devices
  driver core: WQ_PERCPU added to alloc_workqueue users
  driver core: replace use of system_unbound_wq with system_dfl_wq
  tick/nohz: Expose housekeeping CPUs in sysfs
  tick/nohz: avoid showing '(null)' if nohz_full= not set
  sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute
  kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node
  fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE
  mod_devicetable: Bump auxiliary_device_id name size
  sysfs: simplify attribute definition macros
  samples/kobject: constify 'struct foo_attribute'
  samples/kobject: add is_visible() callback to attribute group
  sysfs: attribute_group: enable const variants of is_visible()
  sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE()
  sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS()
  sysfs: attribute_group: allow registration of const attribute
  ...
2025-12-05 21:29:02 -08:00
Linus Torvalds 7cd122b552 Some filesystems use a kinda-sorta controlled dentry refcount leak to pin
dentries of created objects in dcache (and undo it when removing those).
 Reference is grabbed and not released, but it's not actually _stored_
 anywhere.  That works, but it's hard to follow and verify; among other
 things, we have no way to tell _which_ of the increments is intended
 to be an unpaired one.  Worse, on removal we need to decide whether
 the reference had already been dropped, which can be non-trivial if
 that removal is on umount and we need to figure out if this dentry is
 pinned due to e.g. unlink() not done.  Usually that is handled by using
 kill_litter_super() as ->kill_sb(), but there are open-coded special
 cases of the same (consider e.g. /proc/self).
 
 Things get simpler if we introduce a new dentry flag (DCACHE_PERSISTENT)
 marking those "leaked" dentries.  Having it set claims responsibility
 for +1 in refcount.
 
 The end result this series is aiming for:
 
 * get these unbalanced dget() and dput() replaced with new primitives that
   would, in addition to adjusting refcount, set and clear persistency flag.
 * instead of having kill_litter_super() mess with removing the remaining
   "leaked" references (e.g. for all tmpfs files that hadn't been removed
   prior to umount), have the regular shrink_dcache_for_umount() strip
   DCACHE_PERSISTENT of all dentries, dropping the corresponding
   reference if it had been set.  After that kill_litter_super() becomes
   an equivalent of kill_anon_super().
 
 Doing that in a single step is not feasible - it would affect too many places
 in too many filesystems.  It has to be split into a series.
 
 This work has really started early in 2024; quite a few preliminary pieces
 have already gone into mainline.  This chunk is finally getting to the
 meat of that stuff - infrastructure and most of the conversions to it.
 
 Some pieces are still sitting in the local branches, but the bulk of
 that stuff is here.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull persistent dentry infrastructure and conversion from Al Viro:
 "Some filesystems use a kinda-sorta controlled dentry refcount leak to
  pin dentries of created objects in dcache (and undo it when removing
  those). A reference is grabbed and not released, but it's not actually
  _stored_ anywhere.

  That works, but it's hard to follow and verify; among other things, we
  have no way to tell _which_ of the increments is intended to be an
  unpaired one. Worse, on removal we need to decide whether the
  reference had already been dropped, which can be non-trivial if that
  removal is on umount and we need to figure out if this dentry is
  pinned due to e.g. unlink() not done. Usually that is handled by using
  kill_litter_super() as ->kill_sb(), but there are open-coded special
  cases of the same (consider e.g. /proc/self).

  Things get simpler if we introduce a new dentry flag
  (DCACHE_PERSISTENT) marking those "leaked" dentries. Having it set
  claims responsibility for +1 in refcount.

  The end result this series is aiming for:

   - get these unbalanced dget() and dput() replaced with new primitives
     that would, in addition to adjusting refcount, set and clear
     persistency flag.

   - instead of having kill_litter_super() mess with removing the
     remaining "leaked" references (e.g. for all tmpfs files that hadn't
     been removed prior to umount), have the regular
     shrink_dcache_for_umount() strip DCACHE_PERSISTENT of all dentries,
     dropping the corresponding reference if it had been set. After that
     kill_litter_super() becomes an equivalent of kill_anon_super().

  Doing that in a single step is not feasible - it would affect too many
  places in too many filesystems. It has to be split into a series.

  This work has really started early in 2024; quite a few preliminary
  pieces have already gone into mainline. This chunk is finally getting
  to the meat of that stuff - infrastructure and most of the conversions
  to it.

  Some pieces are still sitting in the local branches, but the bulk of
  that stuff is here"

* tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  d_make_discardable(): warn if given a non-persistent dentry
  kill securityfs_recursive_remove()
  convert securityfs
  get rid of kill_litter_super()
  convert rust_binderfs
  convert nfsctl
  convert rpc_pipefs
  convert hypfs
  hypfs: swich hypfs_create_u64() to returning int
  hypfs: switch hypfs_create_str() to returning int
  hypfs: don't pin dentries twice
  convert gadgetfs
  gadgetfs: switch to simple_remove_by_name()
  convert functionfs
  functionfs: switch to simple_remove_by_name()
  functionfs: fix the open/removal races
  functionfs: need to cancel ->reset_work in ->kill_sb()
  functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}()
  functionfs: don't abuse ffs_data_closed() on fs shutdown
  convert selinuxfs
  ...
2025-12-05 14:36:21 -08:00
Aaron Thompson d3666c1f8a debugfs: Fix default access mode config check
This typo caused debugfs to always behave as if
CONFIG_DEBUG_FS_ALLOW_NONE was selected.

Fixes: f278809475 ("debugfs: Remove broken no-mount mode")
Reported-by: Mark Brown <broonie@kernel.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: Aaron Thompson <dev@aaront.org>
Link: https://patch.msgid.link/20251202070927.14198-1-dev@null.aaront.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-12-02 09:31:51 +01:00
Aaron Thompson f278809475 debugfs: Remove broken no-mount mode
debugfs access modes were added in Linux 5.10 (Dec 2020) [1], but the
no-mount mode has behaved effectively the same as the off mode since
Linux 5.12 (Apr 2021) [2]. The only difference is the specific error
code returned by the debugfs_create_* functions, which is -ENOENT in
no-mount mode and -EPERM in off mode.

Given that no-mount hasn't worked for several years with no complaints,
just remove it.

[1] a24c6f7bc9 ("debugfs: Add access restriction option")

[2] bc6de804d3 ("debugfs: be more robust at handling improper input in debugfs_lookup()")
    56348560d4 ("debugfs: do not attempt to create a new file before the filesystem is initalized")

Signed-off-by: Aaron Thompson <dev@aaront.org>
Link: https://patch.msgid.link/20251120102222.18371-3-dev@null.aaront.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-27 10:45:20 +01:00
Aaron Thompson 3ae94a55d0 debugfs: Remove redundant access mode checks
debugfs_get_tree() can only be called if debugfs itself calls
simple_pin_fs() or register_filesystem(), and those call paths also
check the access mode.

debugfs_start_creating() checks the access mode so the checks in the
debugfs_create_* functions are unnecessary.

An upcoming change will affect debugfs_allow, so doing this cleanup
first will make that change simpler.

Signed-off-by: Aaron Thompson <dev@aaront.org>
Link: https://patch.msgid.link/20251120102222.18371-2-dev@null.aaront.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-27 10:45:20 +01:00
Al Viro 0703b36e4e debugfs: remove duplicate checks in callers of start_creating()
we'd already verified that DEBUGFS_ALLOW_API was there in
start_creating() - it would've failed otherwise

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-11-16 01:35:03 -05:00
Al Viro ebb54484c3 convert debugfs
similar to tracefs - simulation of normal codepath for creation,
simple_recursive_removal() for removal.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-11-16 01:35:03 -05:00
NeilBrown 833d2b3a07
Add start_renaming_two_dentries()
A few callers want to lock for a rename and already have both dentries.
Also debugfs does want to perform a lookup but doesn't want permission
checking, so start_renaming_dentry() cannot be used.

This patch introduces start_renaming_two_dentries() which is given both
dentries.  debugfs performs one lookup itself.  As it will only continue
with a negative dentry and as those cannot be renamed or unlinked, it is
safe to do the lookup before getting the rename locks.

overlayfs uses start_renaming_two_dentries() in three places and  selinux
uses it twice in sel_make_policy_nodes().

In sel_make_policy_nodes() we now lock for rename twice instead of just
once so the combined operation is no longer atomic w.r.t the parent
directory locks.  As selinux_state.policy_mutex is held across the whole
operation this does not open up any interesting races.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20251113002050.676694-13-neilb@ownmail.net
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-14 13:15:58 +01:00
NeilBrown 8b45b9a882
debugfs: rename end_creating() to debugfs_end_creating()
By not using the generic end_creating() name here we are free to use it
more globally for a more generic function.
This should have been done when start_creating() was renamed.

For consistency, also rename failed_creating().

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NeilBrown <neil@brown.name>
Link: https://patch.msgid.link/20251113002050.676694-2-neilb@ownmail.net
Tested-by: syzbot@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-14 13:15:55 +01:00
Linus Torvalds 449c2b302c vfs-6.18-rc1.async
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Merge tag 'vfs-6.18-rc1.async' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs async directory updates from Christian Brauner:
 "This contains further preparatory changes for the asynchronous directory
  locking scheme:

   - Add lookup_one_positive_killable() which allows overlayfs to
     perform lookup that won't block on a fatal signal

   - Unify the mount idmap handling in struct renamedata as a rename can
     only happen within a single mount

   - Introduce kern_path_parent() for audit which sets the path to the
     parent and returns a dentry for the target without holding any
     locks on return

   - Rename kern_path_locked() as it is only used to prepare for the
     removal of an object from the filesystem:

	kern_path_locked()    => start_removing_path()
	kern_path_create()    => start_creating_path()
	user_path_create()    => start_creating_user_path()
	user_path_locked_at() => start_removing_user_path_at()
	done_path_create()    => end_creating_path()
	NA                    => end_removing_path()"

* tag 'vfs-6.18-rc1.async' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  debugfs: rename start_creating() to debugfs_start_creating()
  VFS: rename kern_path_locked() and related functions.
  VFS/audit: introduce kern_path_parent() for audit
  VFS: unify old_mnt_idmap and new_mnt_idmap in renamedata
  VFS: discard err2 in filename_create()
  VFS/ovl: add lookup_one_positive_killable()
2025-09-29 11:55:15 -07:00
NeilBrown 0a2c705947
debugfs: rename start_creating() to debugfs_start_creating()
start_creating() is a generic name which I would like to use for a
function similar to simple_start_creating(), only not quite so simple.

debugfs is using this name which, though static, will cause complaints
if then name is given a different signature in a header file.

So rename it to debugfs_start_creating().

Signed-off-by: NeilBrown <neil@brown.name>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-23 12:37:36 +02:00
Charalampos Mitrodimas ba6cc29351 debugfs: fix mount options not being applied
Mount options (uid, gid, mode) are silently ignored when debugfs is
mounted. This is a regression introduced during the conversion to the
new mount API.

When the mount API conversion was done, the parsed options were never
applied to the superblock when it was reused. As a result, the mount
options were ignored when debugfs was mounted.

Fix this by following the same pattern as the tracefs fix in commit
e4d32142d1 ("tracing: Fix tracefs mount options"). Call
debugfs_reconfigure() in debugfs_get_tree() to apply the mount options
to the superblock after it has been created or reused.

As an example, with the bug the "mode" mount option is ignored:

  $ mount -o mode=0666 -t debugfs debugfs /tmp/debugfs_test
  $ mount | grep debugfs_test
  debugfs on /tmp/debugfs_test type debugfs (rw,relatime)
  $ ls -ld /tmp/debugfs_test
  drwx------ 25 root root 0 Aug  4 14:16 /tmp/debugfs_test

With the fix applied, it works as expected:

  $ mount -o mode=0666 -t debugfs debugfs /tmp/debugfs_test
  $ mount | grep debugfs_test
  debugfs on /tmp/debugfs_test type debugfs (rw,relatime,mode=666)
  $ ls -ld /tmp/debugfs_test
  drw-rw-rw- 37 root root 0 Aug  2 17:28 /tmp/debugfs_test

Fixes: a20971c187 ("vfs: Convert debugfs to use the new mount API")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220406
Cc: stable <stable@kernel.org>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Charalampos Mitrodimas <charmitro@posteo.net>
Link: https://lore.kernel.org/r/20250816-debugfs-mount-opts-v3-1-d271dad57b5b@posteo.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-17 12:22:25 +02:00
Linus Torvalds 22c5696e3f Driver core changes for 6.17-rc1
- DEBUGFS
 
   - Remove unneeded debugfs_file_{get,put}() instances
 
   - Remove last remnants of debugfs_real_fops()
 
   - Allow storing non-const void * in struct debugfs_inode_info::aux
 
 - SYSFS
 
   - Switch back to attribute_group::bin_attrs (treewide)
 
   - Switch back to bin_attribute::read()/write() (treewide)
 
   - Constify internal references to 'struct bin_attribute'
 
 - Support cache-ids for device-tree systems
 
   - Add arch hook arch_compact_of_hwid()
 
   - Use arch_compact_of_hwid() to compact MPIDR values on arm64
 
 - Rust
 
   - Device
 
     - Introduce CoreInternal device context (for bus internal methods)
 
     - Provide generic drvdata accessors for bus devices
 
     - Provide Driver::unbind() callbacks
 
     - Use the infrastructure above for auxiliary, PCI and platform
 
     - Implement Device::as_bound()
 
     - Rename Device::as_ref() to Device::from_raw() (treewide)
 
     - Implement fwnode and device property abstractions
 
       - Implement example usage in the Rust platform sample driver
 
   - Devres
 
     - Remove the inner reference count (Arc) and use pin-init instead
 
     - Replace Devres::new_foreign_owned() with devres::register()
 
     - Require T to be Send in Devres<T>
 
     - Initialize the data kept inside a Devres last
 
     - Provide an accessor for the Devres associated Device
 
   - Device ID
 
     - Add support for ACPI device IDs and driver match tables
 
     - Split up generic device ID infrastructure
 
     - Use generic device ID infrastructure in net::phy
 
   - DMA
 
     - Implement the dma::Device trait
 
     - Add DMA mask accessors to dma::Device
 
     - Implement dma::Device for PCI and platform devices
 
     - Use DMA masks from the DMA sample module
 
   - I/O
 
     - Implement abstraction for resource regions (struct resource)
 
     - Implement resource-based ioremap() abstractions
 
     - Provide platform device accessors for I/O (remap) requests
 
   - Misc
 
     - Support fallible PinInit types in Revocable
 
     - Implement Wrapper<T> for Opaque<T>
 
     - Merge pin-init blanket dependencies (for Devres)
 
 - Misc
 
   - Fix OF node leak in auxiliary_device_create()
 
   - Use util macros in device property iterators
 
   - Improve kobject sample code
 
   - Add device_link_test() for testing device link flags
 
   - Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits
 
   - Hint to prefer container_of_const() over container_of()
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Merge tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Remove unneeded debugfs_file_{get,put}() instances
   - Remove last remnants of debugfs_real_fops()
   - Allow storing non-const void * in struct debugfs_inode_info::aux

  sysfs:
   - Switch back to attribute_group::bin_attrs (treewide)
   - Switch back to bin_attribute::read()/write() (treewide)
   - Constify internal references to 'struct bin_attribute'

  Support cache-ids for device-tree systems:
   - Add arch hook arch_compact_of_hwid()
   - Use arch_compact_of_hwid() to compact MPIDR values on arm64

  Rust:
   - Device:
       - Introduce CoreInternal device context (for bus internal methods)
       - Provide generic drvdata accessors for bus devices
       - Provide Driver::unbind() callbacks
       - Use the infrastructure above for auxiliary, PCI and platform
       - Implement Device::as_bound()
       - Rename Device::as_ref() to Device::from_raw() (treewide)
       - Implement fwnode and device property abstractions
       - Implement example usage in the Rust platform sample driver
   - Devres:
       - Remove the inner reference count (Arc) and use pin-init instead
       - Replace Devres::new_foreign_owned() with devres::register()
       - Require T to be Send in Devres<T>
       - Initialize the data kept inside a Devres last
       - Provide an accessor for the Devres associated Device
   - Device ID:
       - Add support for ACPI device IDs and driver match tables
       - Split up generic device ID infrastructure
       - Use generic device ID infrastructure in net::phy
   - DMA:
       - Implement the dma::Device trait
       - Add DMA mask accessors to dma::Device
       - Implement dma::Device for PCI and platform devices
       - Use DMA masks from the DMA sample module
   - I/O:
       - Implement abstraction for resource regions (struct resource)
       - Implement resource-based ioremap() abstractions
       - Provide platform device accessors for I/O (remap) requests
   - Misc:
       - Support fallible PinInit types in Revocable
       - Implement Wrapper<T> for Opaque<T>
       - Merge pin-init blanket dependencies (for Devres)

  Misc:
   - Fix OF node leak in auxiliary_device_create()
   - Use util macros in device property iterators
   - Improve kobject sample code
   - Add device_link_test() for testing device link flags
   - Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits
   - Hint to prefer container_of_const() over container_of()"

* tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (84 commits)
  rust: io: fix broken intra-doc links to `platform::Device`
  rust: io: fix broken intra-doc link to missing `flags` module
  rust: io: mem: enable IoRequest doc-tests
  rust: platform: add resource accessors
  rust: io: mem: add a generic iomem abstraction
  rust: io: add resource abstraction
  rust: samples: dma: set DMA mask
  rust: platform: implement the `dma::Device` trait
  rust: pci: implement the `dma::Device` trait
  rust: dma: add DMA addressing capabilities
  rust: dma: implement `dma::Device` trait
  rust: net::phy Change module_phy_driver macro to use module_device_table macro
  rust: net::phy represent DeviceId as transparent wrapper over mdio_device_id
  rust: device_id: split out index support into a separate trait
  device: rust: rename Device::as_ref() to Device::from_raw()
  arm64: cacheinfo: Provide helper to compress MPIDR value into u32
  cacheinfo: Add arch hook to compress CPU h/w id into 32 bits for cache-id
  cacheinfo: Set cache 'id' based on DT data
  container_of: Document container_of() is not to be used in new code
  driver core: auxiliary bus: fix OF node leak
  ...
2025-07-29 12:15:39 -07:00
Linus Torvalds ddf52f12ef Massage rpc_pipefs to use saner primitives and clean up the
APIs provided to the rest of the kernel.
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Merge tag 'pull-rpc_pipefs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull rpc_pipefs updates from Al Viro:
 "Massage rpc_pipefs to use saner primitives and clean up the APIs
  provided to the rest of the kernel"

* tag 'pull-rpc_pipefs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  rpc_create_client_dir(): return 0 or -E...
  rpc_create_client_dir(): don't bother with rpc_populate()
  rpc_new_dir(): the last argument is always NULL
  rpc_pipe: expand the calls of rpc_mkdir_populate()
  rpc_gssd_dummy_populate(): don't bother with rpc_populate()
  rpc_mkpipe_dentry(): switch to simple_start_creating()
  rpc_pipe: saner primitive for creating regular files
  rpc_pipe: saner primitive for creating subdirectories
  rpc_pipe: don't overdo directory locking
  rpc_mkpipe_dentry(): saner calling conventions
  rpc_unlink(): saner calling conventions
  rpc_populate(): lift cleanup into callers
  rpc_unlink(): use simple_recursive_removal()
  rpc_{rmdir_,}depopulate(): use simple_recursive_removal() instead
  rpc_pipe: clean failure exits in fill_super
  new helper: simple_start_creating()
2025-07-28 09:56:09 -07:00
Al Viro 9d3b96be2e debugfs_get_aux(): allow storing non-const void *
typechecking is up to users, anyway...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20250702212616.GI3406663@ZenIV
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-09 13:30:29 +02:00
Al Viro 59200f4526 new helper: simple_start_creating()
Set the things up for kernel-initiated creation of object in
a tree-in-dcache filesystem.  With respect to locking it's
an equivalent of filename_create() - we either get a negative
dentry with locked parent, or ERR_PTR() and no locks taken.

tracefs and debugfs had that open-coded as part of their
object creation machinery; switched to calling new helper.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-07-02 22:44:38 -04:00
Al Viro 82a3c881cd debugfs: use DCACHE_DONTCACHE
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-06-11 13:41:05 -04:00
Al Viro 05fb0e6664 new helper: set_default_d_op()
... to be used instead of manually assigning to ->s_d_op.
All in-tree filesystem converted (and field itself is renamed,
so any out-of-tree ones in need of conversion will be caught
by compiler).

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-06-10 22:21:16 -04:00
NeilBrown fa6fe07d15
VFS: rename lookup_one_len family to lookup_noperm and remove permission check
The lookup_one_len family of functions is (now) only used internally by
a filesystem on itself either
- in a context where permission checking is irrelevant such as by a
  virtual filesystem populating itself, or xfs accessing its ORPHANAGE
  or dquota accessing the quota file; or
- in a context where a permission check (MAY_EXEC on the parent) has just
  been performed such as a network filesystem finding in "silly-rename"
  file in the same directory.  This is also the context after the
  _parentat() functions where currently lookup_one_qstr_excl() is used.

So the permission check is pointless.

The name "one_len" is unhelpful in understanding the purpose of these
functions and should be changed.  Most of the callers pass the len as
"strlen()" so using a qstr and QSTR() can simplify the code.

This patch renames these functions (include lookup_positive_unlocked()
which is part of the family despite the name) to have a name based on
"lookup_noperm".  They are changed to receive a 'struct qstr' instead
of separate name and len.  In a few cases the use of QSTR() results in a
new call to strlen().

try_lookup_noperm() takes a pointer to a qstr instead of the whole
qstr.  This is consistent with d_hash_and_lookup() (which is nearly
identical) and useful for lookup_noperm_unlocked().

The new lookup_noperm_common() doesn't take a qstr yet.  That will be
tidied up in a subsequent patch.

Signed-off-by: NeilBrown <neil@brown.name>
Link: https://lore.kernel.org/r/20250319031545.2999807-5-neil@brown.name
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-04-08 11:24:36 +02:00
Al Viro f7862dfef6 saner replacement for debugfs_rename()
Existing primitive has several problems:
	1) calling conventions are clumsy - it returns a dentry reference
that is either identical to its second argument or is an ERR_PTR(-E...);
in both cases no refcount changes happen.  Inconvenient for users and
bug-prone; it would be better to have it return 0 on success and -E... on
failure.
	2) it allows cross-directory moves; however, no such caller have
ever materialized and considering the way debugfs is used, it's unlikely
to happen in the future.  What's more, any such caller would have fun
issues to deal with wrt interplay with recursive removal.  It also makes
the calling conventions clumsier...
	3) tautological rename fails; the callers have no race-free way
to deal with that.
	4) new name must have been formed by the caller; quite a few
callers have it done by sprintf/kasprintf/etc., ending up with considerable
boilerplate.

Proposed replacement: int debugfs_change_name(dentry, fmt, ...).  All callers
convert to that easily, and it's simpler internally.

IMO debugfs_rename() should go; if we ever get a real-world use case for
cross-directory moves in debugfs, we can always look into the right way
to handle that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20250112080705.141166-21-viro@zeniv.linux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-15 13:14:37 +01:00
Al Viro 12c9209893 debugfs: allow to store an additional opaque pointer at file creation
Set by debugfs_create_file_aux(name, mode, parent, data, aux, fops).
Plain debugfs_create_file() has it set to NULL.
Accessed by debugfs_get_aux(file).

Convenience macros for numeric opaque data - debugfs_create_file_aux_num
and debugfs_get_aux_num, resp.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20250112080705.141166-5-viro@zeniv.linux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-15 13:14:36 +01:00
Al Viro 95688800ee debugfs: don't mess with bits in ->d_fsdata
The reason we need that crap is the dual use ->d_fsdata has there -
it's both holding a debugfs_fsdata reference after the first
debugfs_file_get() (actually, after the call of proxy ->open())
*and* it serves as a place to stash a reference to real file_operations
from object creation to the first open.  Oh, and it's triple use,
actually - that stashed reference might be to debugfs_short_fops.

Bugger that for a game of solidiers - just put the operations
reference into debugfs-private augmentation of inode.  And split
debugfs_full_file_operations into full and short cases, so that
debugfs_get_file() could tell one from another.

Voila - ->d_fsdata holds NULL until the first (successful) debugfs_get_file()
and a reference to struct debugfs_fsdata afterwards.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20250112080705.141166-4-viro@zeniv.linux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-15 13:14:35 +01:00
Al Viro bacaaf833e debugfs: move ->automount into debugfs_inode_info
... and don't bother with debugfs_fsdata for those.  Life's
simpler that way...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20250112080705.141166-2-viro@zeniv.linux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-15 13:14:35 +01:00
Al Viro 268b36116f debugfs: separate cache for debugfs inodes
Embed them into container (struct debugfs_inode_info, with nothing
else in it at the moment), set the cache up, etc.

Just the infrastructure changes letting us augment debugfs inodes
here; adding stuff will come at the next step.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20250112080705.141166-1-viro@zeniv.linux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-15 13:14:35 +01:00
Al Viro 24edfbdedf debugfs: fix missing mutex_destroy() in short_fops case
we need that in ->real_fops == NULL, ->short_fops != NULL case

Fixes: 8dc6d81c6b "debugfs: add small file operations for most files"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20241229081223.3193228-1-viro@zeniv.linux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-07 16:20:11 +01:00
Johannes Berg f8f25893a4 fs: debugfs: differentiate short fops with proxy ops
Geert reported that my previous short fops debugfs changes
broke m68k, because it only has mandatory alignement of two,
so we can't stash the "is it short" information into the
pointer (as we already did with the "is it real" bit.)

Instead, exploit the fact that debugfs_file_get() called on
an already open file will already find that the fsdata is
no longer the real fops but rather the allocated data that
already distinguishes full/short ops, so only open() needs
to be able to distinguish. We can achieve that by using two
different open functions.

Unfortunately this requires another set of full file ops,
increasing the size by 536 bytes (x86-64), but that's still
a reasonable trade-off given that only converting some of
the wireless stack gained over 28k. This brings the total
cost of this to around 1k, for wins of 28k (all x86-64).

Reported-and-tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/CAMuHMdWu_9-L2Te101w8hU7H_2yobJFPXSwwUmGHSJfaPWDKiQ@mail.gmail.com
Fixes: 8dc6d81c6b ("debugfs: add small file operations for most files")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20241129121536.30989-2-johannes@sipsolutions.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-07 16:20:08 +01:00
Johannes Berg 8dc6d81c6b debugfs: add small file operations for most files
As struct file_operations is really big, but (most) debugfs
files only use simple_open, read, write and perhaps seek, and
don't need anything else, this wastes a lot of space for NULL
pointers.

Add a struct debugfs_short_fops and some bookkeeping code in
debugfs so that users can use that with debugfs_create_file()
using _Generic to figure out which function to use.

Converting mac80211 to use it where possible saves quite a
bit of space:

1010127  205064    1220 1216411  128f9b net/mac80211/mac80211.ko (before)
 981199  205064    1220 1187483  121e9b net/mac80211/mac80211.ko (after)
-------
 -28928 = ~28KiB

With a marginal space cost in debugfs:

   8701	    550	     16	   9267	   2433	fs/debugfs/inode.o (before)
  25233	    325	     32	  25590	   63f6	fs/debugfs/file.o  (before)
   8914	    558	     16	   9488	   2510	fs/debugfs/inode.o (after)
  25380	    325	     32	  25737	   6489	fs/debugfs/file.o  (after)
---------------
   +360      +8

(All on x86-64)

A simple spatch suggests there are more than 300 instances,
not even counting the ones hidden in macros like in mac80211,
that could be trivially converted, for additional savings of
about 240 bytes for each.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/20241022151838.26f9925fb959.Ia80b55e934bbfc45ce0df42a3233d34b35508046@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-10-23 16:47:01 +02:00
Marc Aurèle La France 3a987b88a4 debugfs show actual source in /proc/mounts
After its conversion to the new mount API, debugfs displays "none" in
/proc/mounts instead of the actual source.  Fix this by recognising its
"source" mount option.

Signed-off-by: Marc Aurèle La France <tsi@tuyoix.net>
Link: https://lore.kernel.org/r/e439fae2-01da-234b-75b9-2a7951671e27@tuyoix.net
Fixes: a20971c187 ("vfs: Convert debugfs to use the new mount API")
Cc: stable@vger.kernel.org # 6.10.x: 49abee5991e1: debugfs: Convert to new uid/gid option parsing helpers
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-08-30 08:22:37 +02:00
Linus Torvalds b8fc1bd73a vfs-6.11.mount.api
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Merge tag 'vfs-6.11.mount.api' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs mount API updates from Christian Brauner:

 - Add a generic helper to parse uid and gid mount options.

   Currently we open-code the same logic in various filesystems which is
   error prone, especially since the verification of uid and gid mount
   options is a sensitive operation in the face of idmappings.

   Add a generic helper and convert all filesystems over to it. Make
   sure that filesystems that are mountable in unprivileged containers
   verify that the specified uid and gid can be represented in the
   owning namespace of the filesystem.

 - Convert hostfs to the new mount api.

* tag 'vfs-6.11.mount.api' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fuse: Convert to new uid/gid option parsing helpers
  fuse: verify {g,u}id mount options correctly
  fat: Convert to new uid/gid option parsing helpers
  fat: Convert to new mount api
  fat: move debug into fat_mount_options
  vboxsf: Convert to new uid/gid option parsing helpers
  tracefs: Convert to new uid/gid option parsing helpers
  smb: client: Convert to new uid/gid option parsing helpers
  tmpfs: Convert to new uid/gid option parsing helpers
  ntfs3: Convert to new uid/gid option parsing helpers
  isofs: Convert to new uid/gid option parsing helpers
  hugetlbfs: Convert to new uid/gid option parsing helpers
  ext4: Convert to new uid/gid option parsing helpers
  exfat: Convert to new uid/gid option parsing helpers
  efivarfs: Convert to new uid/gid option parsing helpers
  debugfs: Convert to new uid/gid option parsing helpers
  autofs: Convert to new uid/gid option parsing helpers
  fs_parse: add uid & gid option option parsing helpers
  hostfs: Add const qualifier to host_root in hostfs_fill_super()
  hostfs: convert hostfs to use the new mount API
2024-07-15 11:31:32 -07:00
Eric Sandeen 49abee5991
debugfs: Convert to new uid/gid option parsing helpers
Convert to new uid/gid option parsing helpers

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Link: https://lore.kernel.org/r/b2f44ee0-3cee-49eb-a416-f26a9306eb56@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-07-02 06:21:18 +02:00
Christian Brauner 0c07c273a5
debugfs: continue to ignore unknown mount options
Wolfram reported that debugfs remained empty on some of his boards
triggering the message "debugfs: Unknown parameter 'auto'".

The root of the issue is that we ignored unknown mount options in the
old mount api but we started rejecting unknown mount options in the new
mount api. Continue to ignore unknown mount options to not regress
userspace.

Fixes: a20971c187 ("vfs: Convert debugfs to use the new mount API")
Link: https://lore.kernel.org/r/20240527100618.np2wqiw5mz7as3vk@ninjato
Reported-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-05-28 14:32:42 +02:00
David Howells a20971c187
vfs: Convert debugfs to use the new mount API
Convert the debugfs filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
Co-developed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[sandeen: forward port to modern kernel, fix remounting]
Link: https://lore.kernel.org/r/49d1f108-46e3-443f-85a3-6dd730c5d076@redhat.com
cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-03-26 09:04:54 +01:00
Johannes Berg 952c3fce29 debugfs: fix wait/cancellation handling during remove
Ben Greear further reports deadlocks during concurrent debugfs
remove while files are being accessed, even though the code in
question now uses debugfs cancellations. Turns out that despite
all the review on the locking, we missed completely that the
logic is wrong: if the refcount hits zero we can finish (and
need not wait for the completion), but if it doesn't we have
to trigger all the cancellations. As written, we can _never_
get into the loop triggering the cancellations. Fix this, and
explain it better while at it.

Cc: stable@vger.kernel.org
Fixes: 8c88a47435 ("debugfs: add API to allow debugfs operations cancellation")
Reported-by: Ben Greear <greearb@candelatech.com>
Closes: https://lore.kernel.org/r/1c9fa9e5-09f1-0522-fdbc-dbcef4d255ca@candelatech.com
Tested-by: Madhan Sai <madhan.singaraju@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20240229153635.6bfab7eb34d3.I6c7aeff8c9d6628a8bc1ddcf332205a49d801f17@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-07 22:08:15 +00:00
Johannes Berg 88ac06a9f9 Revert "debugfs: annotate debugfs handlers vs. removal with lockdep"
This reverts commit f4acfcd4de ("debugfs: annotate debugfs handlers
vs. removal with lockdep"), it appears to have false positives and
really shouldn't have been in the -rc series with the fixes anyway.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20231202114936.fd55431ab160.I911aa53abeeca138126f690d383a89b13eb05667@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-04 07:43:16 +01:00
Jakub Kicinski 300fbb247e wireless fixes:
- debugfs had a deadlock (removal vs. use of files),
    fixes going through wireless ACKed by Greg
  - support for HT STAs on 320 MHz channels, even if it's
    not clear that should ever happen (that's 6 GHz), best
    not to WARN()
  - fix for the previous CQM fix that broke most cases
  - various wiphy locking fixes
  - various small driver fixes
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Merge tag 'wireless-2023-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless

Johannes Berg says:

====================
wireless fixes:
 - debugfs had a deadlock (removal vs. use of files),
   fixes going through wireless ACKed by Greg
 - support for HT STAs on 320 MHz channels, even if it's
   not clear that should ever happen (that's 6 GHz), best
   not to WARN()
 - fix for the previous CQM fix that broke most cases
 - various wiphy locking fixes
 - various small driver fixes

* tag 'wireless-2023-11-29' of git://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless:
  wifi: mac80211: use wiphy locked debugfs for sdata/link
  wifi: mac80211: use wiphy locked debugfs helpers for agg_status
  wifi: cfg80211: add locked debugfs wrappers
  debugfs: add API to allow debugfs operations cancellation
  debugfs: annotate debugfs handlers vs. removal with lockdep
  debugfs: fix automount d_fsdata usage
  wifi: mac80211: handle 320 MHz in ieee80211_ht_cap_ie_to_sta_ht_cap
  wifi: avoid offset calculation on NULL pointer
  wifi: cfg80211: hold wiphy mutex for send_interface
  wifi: cfg80211: lock wiphy mutex for rfkill poll
  wifi: cfg80211: fix CQM for non-range use
  wifi: mac80211: do not pass AP_VLAN vif pointer to drivers during flush
  wifi: iwlwifi: mvm: fix an error code in iwl_mvm_mld_add_sta()
  wifi: mt76: mt7925: fix typo in mt7925_init_he_caps
  wifi: mt76: mt7921: fix 6GHz disabled by the missing default CLC config
====================

Link: https://lore.kernel.org/r/20231129150809.31083-3-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-29 19:43:34 -08:00
Johannes Berg 8c88a47435 debugfs: add API to allow debugfs operations cancellation
In some cases there might be longer-running hardware accesses
in debugfs files, or attempts to acquire locks, and we want
to still be able to quickly remove the files.

Introduce a cancellations API to use inside the debugfs handler
functions to be able to cancel such operations on a per-file
basis.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2023-11-27 11:24:55 +01:00
Johannes Berg f4acfcd4de debugfs: annotate debugfs handlers vs. removal with lockdep
When you take a lock in a debugfs handler but also try
to remove the debugfs file under that lock, things can
deadlock since the removal has to wait for all users
to finish.

Add lockdep annotations in debugfs_file_get()/_put()
to catch such issues.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2023-11-27 11:24:50 +01:00
Johannes Berg 0ed04a1847 debugfs: fix automount d_fsdata usage
debugfs_create_automount() stores a function pointer in d_fsdata,
but since commit 7c8d469877 ("debugfs: add support for more
elaborate ->d_fsdata") debugfs_release_dentry() will free it, now
conditionally on DEBUGFS_FSDATA_IS_REAL_FOPS_BIT, but that's not
set for the function pointer in automount. As a result, removing
an automount dentry would attempt to free the function pointer.
Luckily, the only user of this (tracing) never removes it.

Nevertheless, it's safer if we just handle the fsdata in one way,
namely either DEBUGFS_FSDATA_IS_REAL_FOPS_BIT or allocated. Thus,
change the automount to allocate it, and use the real_fops in the
data to indicate whether or not automount is filled, rather than
adding a type tag. At least for now this isn't actually needed,
but the next changes will require it.

Also check in debugfs_file_get() that it gets only called
on regular files, just to make things clearer.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2023-11-27 11:24:45 +01:00
Jeff Layton d21b3c321f
debugfs: convert to new timestamp accessors
Convert to using the new inode timestamp accessor functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20231004185347.80880-26-jlayton@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-18 13:26:20 +02:00
Jeff Layton 0f7bda3fcd debugfs: convert to ctime accessor functions
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-32-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-13 10:28:05 +02:00
Linus Torvalds a93e884edf Driver core changes for 6.3-rc1
Here is the large set of driver core changes for 6.3-rc1.
 
 There's a lot of changes this development cycle, most of the work falls
 into two different categories:
   - fw_devlink fixes and updates.  This has gone through numerous review
     cycles and lots of review and testing by lots of different devices.
     Hopefully all should be good now, and Saravana will be keeping a
     watch for any potential regression on odd embedded systems.
   - driver core changes to work to make struct bus_type able to be moved
     into read-only memory (i.e. const)  The recent work with Rust has
     pointed out a number of areas in the driver core where we are
     passing around and working with structures that really do not have
     to be dynamic at all, and they should be able to be read-only making
     things safer overall.  This is the contuation of that work (started
     last release with kobject changes) in moving struct bus_type to be
     constant.  We didn't quite make it for this release, but the
     remaining patches will be finished up for the release after this
     one, but the groundwork has been laid for this effort.
 
 Other than that we have in here:
   - debugfs memory leak fixes in some subsystems
   - error path cleanups and fixes for some never-able-to-be-hit
     codepaths.
   - cacheinfo rework and fixes
   - Other tiny fixes, full details are in the shortlog
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the large set of driver core changes for 6.3-rc1.

  There's a lot of changes this development cycle, most of the work
  falls into two different categories:

   - fw_devlink fixes and updates. This has gone through numerous review
     cycles and lots of review and testing by lots of different devices.
     Hopefully all should be good now, and Saravana will be keeping a
     watch for any potential regression on odd embedded systems.

   - driver core changes to work to make struct bus_type able to be
     moved into read-only memory (i.e. const) The recent work with Rust
     has pointed out a number of areas in the driver core where we are
     passing around and working with structures that really do not have
     to be dynamic at all, and they should be able to be read-only
     making things safer overall. This is the contuation of that work
     (started last release with kobject changes) in moving struct
     bus_type to be constant. We didn't quite make it for this release,
     but the remaining patches will be finished up for the release after
     this one, but the groundwork has been laid for this effort.

  Other than that we have in here:

   - debugfs memory leak fixes in some subsystems

   - error path cleanups and fixes for some never-able-to-be-hit
     codepaths.

   - cacheinfo rework and fixes

   - Other tiny fixes, full details are in the shortlog

  All of these have been in linux-next for a while with no reported
  problems"

[ Geert Uytterhoeven points out that that last sentence isn't true, and
  that there's a pending report that has a fix that is queued up - Linus ]

* tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (124 commits)
  debugfs: drop inline constant formatting for ERR_PTR(-ERROR)
  OPP: fix error checking in opp_migrate_dentry()
  debugfs: update comment of debugfs_rename()
  i3c: fix device.h kernel-doc warnings
  dma-mapping: no need to pass a bus_type into get_arch_dma_ops()
  driver core: class: move EXPORT_SYMBOL_GPL() lines to the correct place
  Revert "driver core: add error handling for devtmpfs_create_node()"
  Revert "devtmpfs: add debug info to handle()"
  Revert "devtmpfs: remove return value of devtmpfs_delete_node()"
  driver core: cpu: don't hand-override the uevent bus_type callback.
  devtmpfs: remove return value of devtmpfs_delete_node()
  devtmpfs: add debug info to handle()
  driver core: add error handling for devtmpfs_create_node()
  driver core: bus: update my copyright notice
  driver core: bus: add bus_get_dev_root() function
  driver core: bus: constify bus_unregister()
  driver core: bus: constify some internal functions
  driver core: bus: constify bus_get_kset()
  driver core: bus: constify bus_register/unregister_notifier()
  driver core: remove private pointer from struct bus_type
  ...
2023-02-24 12:58:55 -08:00
Bagas Sanjaya 88cd618dcc debugfs: drop inline constant formatting for ERR_PTR(-ERROR)
Stephen Rothwell reported htmldocs warning when merging driver-core tree
for linux-next:

Documentation/filesystems/api-summary:146: fs/debugfs/inode.c:804: WARNING: Inline literal start-string without end-string.

The warning is due to inline constant formatting (``%CONST``) doesn't play
nice with complex-name constants like ERR_PTR(-ERROR).

Drop the formatting for that constant above to be consistent with similar
error constants and also to fix the above warning.

Link: https://lore.kernel.org/lkml/20230220163133.481e43d8@canb.auug.org.au/
Fixes: d3002468cb ("debugfs: update comment of debugfs_rename()")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20230220124721.11657-1-bagasdotme@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-20 14:14:56 +01:00
Qi Zheng d3002468cb debugfs: update comment of debugfs_rename()
Since commit ff9fb72bc0 ("debugfs: return error values, not NULL")
changed return value of debugfs_rename() in error cases from %NULL to
%ERR_PTR(-ERROR), the comment of debugfs_rename should also be updated
so as not to mislead readers.

Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Link: https://lore.kernel.org/r/20230208035634.58095-1-zhengqi.arch@bytedance.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-16 13:43:05 +01:00
Christian Brauner e18275ae55
fs: port ->rename() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:26 +01:00
Christian Brauner c1632a0f11
fs: port ->setattr() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:02 +01:00
Brian Norris b8de524ce4 debugfs: Only clobber mode/uid/gid on remount if asked
Users may have explicitly configured their debugfs permissions; we
shouldn't overwrite those just because a second mount appeared.

Only clobber if the options were provided at mount time.

Existing behavior:

  ## Pre-existing status: debugfs is 0755.
  # chmod 755 /sys/kernel/debug/
  # stat -c '%A' /sys/kernel/debug/
  drwxr-xr-x

  ## New mount sets kernel-default permissions:
  # mount -t debugfs none /mnt/foo
  # stat -c '%A' /mnt/foo
  drwx------

  ## Unexpected: the original mount changed permissions:
  # stat -c '%A' /sys/kernel/debug
  drwx------

New behavior:

  ## Pre-existing status: debugfs is 0755.
  # chmod 755 /sys/kernel/debug/
  # stat -c '%A' /sys/kernel/debug/
  drwxr-xr-x

  ## New mount inherits existing permissions:
  # mount -t debugfs none /mnt/foo
  # stat -c '%A' /mnt/foo
  drwxr-xr-x

  ## Expected: old mount is unchanged:
  # stat -c '%A' /sys/kernel/debug
  drwxr-xr-x

Full test cases are being submitted to LTP.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Link: https://lore.kernel.org/r/20220912163042.v3.1.Icbd40fce59f55ad74b80e5d435ea233579348a78@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-24 14:01:37 +02:00
Greg Kroah-Hartman dec9b2f1e0 debugfs: add debugfs_lookup_and_remove()
There is a very common pattern of using
debugfs_remove(debufs_lookup(..)) which results in a dentry leak of the
dentry that was looked up.  Instead of having to open-code the correct
pattern of calling dput() on the dentry, create
debugfs_lookup_and_remove() to handle this pattern automatically and
properly without any memory leaks.

Cc: stable <stable@kernel.org>
Reported-by: Kuyo Chang <kuyo.chang@mediatek.com>
Tested-by: Kuyo Chang <kuyo.chang@mediatek.com>
Link: https://lore.kernel.org/r/YxIaQ8cSinDR881k@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 13:02:34 +02:00
Douglas Anderson 8bcbde2bb1 debugfs: Document that debugfs_create functions need not be error checked
As talked about in commit b792e64021 ("drm: no need to check return
value of debugfs_create functions"), in many cases we can get away
with totally skipping checking the errors of debugfs functions. Let's
document that so people don't add new code that needlessly checks
these errors.

Probably this note could be added to a boatload of functions, but
that's a lot of duplication.  Let's just add it to the two most
frequent ones and hope people will get the idea.

Suggested-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20220222154555.1.I26d364db7a007f8995e8f0dac978673bc8e9f5e2@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-25 11:56:13 +01:00
Nirmoy Das af505cad95 debugfs: debugfs_create_file_size(): use IS_ERR to check for error
debugfs_create_file() returns encoded error so use IS_ERR for checking
return value.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Nirmoy Das <nirmoy.das@amd.com>
Fixes: ff9fb72bc0 ("debugfs: return error values, not NULL")
Cc: stable <stable@vger.kernel.org>
References: https://gitlab.freedesktop.org/drm/amd/-/issues/1686
Link: https://lore.kernel.org/r/20210902102917.2233-1-nirmoy.das@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-21 09:09:06 +02:00
Ondrej Mosnacek 5881fa8dc2 debugfs: fix security_locked_down() call for SELinux
When (ia->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) is zero, then
the SELinux implementation of the locked_down hook might report a denial
even though the operation would actually be allowed.

To fix this, make sure that security_locked_down() is called only when
the return value will be taken into account (i.e. when changing one of
the problematic attributes).

Note: this was introduced by commit 5496197f9b ("debugfs: Restrict
debugfs when the kernel is locked down"), but it didn't matter at that
time, as the SELinux support came in later.

Fixes: 59438b4647 ("security,lockdown,selinux: implement SELinux lockdown")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Link: https://lore.kernel.org/r/20210507125304.144394-1-omosnace@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-18 18:05:59 +02:00