Commit Graph

324 Commits

Author SHA1 Message Date
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>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCaTEq1wAKCRBZ7Krx/gZQ
 643uAQC1rRslhw5l7OjxEpIYbGG4M+QaadN4Nf5Sr2SuTRaPJQD/W4oj/u4C2eCw
 Dd3q071tqyvm/PXNgN2EEnIaxlFUlwc=
 =rKq+
 -----END PGP SIGNATURE-----

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
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
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaNZQkAAKCRCRxhvAZXjc
 oijOAQCw+gE9GkvYJ7TOCiqVFj8RZZ1tb7NiCdBRCa4wXM7KMwD9Gwim//G8Hjyy
 dNPZejphGdxv99Skwp/0nfyDGL6x7w4=
 =zIJf
 -----END PGP SIGNATURE-----

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()
 -----BEGIN PGP SIGNATURE-----
 
 iHQEABYKAB0WIQS2q/xV6QjXAdC7k+1FlHeO1qrKLgUCaIjkhwAKCRBFlHeO1qrK
 LpXuAP9RWwfD9ZGgQZ9OsMk/0pZ2mDclaK97jcmI9TAeSxeZMgD1FHnOMTY7oSIi
 iG7Muq0yLD+A5gk9HUnMUnFNrngWCg==
 =jgRj
 -----END PGP SIGNATURE-----

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.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCaIRDbQAKCRBZ7Krx/gZQ
 63n6APwNnJXwgtSDi9N0FfHOlYqYSCaCjezVLbq+GR8K+r4wowD/TX/A4Qbyjjic
 /VG8VbYe6fRaD53vp1giGI/dJiTI2Qg=
 =Ta4H
 -----END PGP SIGNATURE-----

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 d9bc88aa54 debugfs: split short and full proxy wrappers, kill debugfs_real_fops()
All users outside of fs/debugfs/file.c are gone, in there we can just
fully split the wrappers for full and short cases and be done with that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20250702212419.GG3406663@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 57b314752e debugfs: Fix the missing initializations in __debugfs_file_get()
both method table pointers in debugfs_fsdata need to be initialized,
obviously, and calculating the bitmap of present methods would also
go better if we start with initialized state.

Fixes: 41a0ecc099 ("debugfs: get rid of dynamically allocation proxy_ops")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20250129191937.GR1977892@ZenIV
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-30 08:22:31 +01:00
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 41a0ecc099 debugfs: get rid of dynamically allocation proxy_ops
All it takes is having full_proxy_open() collect the information
about available methods and store it in debugfs_fsdata.

Wrappers are called only after full_proxy_open() has succeeded
calling debugfs_get_file(), so they are guaranteed to have
->d_fsdata already pointing to debugfs_fsdata.

As the result, they can check if method is absent and bugger off
early, without any atomic operations, etc. - same effect as what
we'd have from NULL method.  Which makes the entire proxy_fops
contents unconditional, making it completely pointless - we can
just put those methods (unconditionally) into
debugfs_full_proxy_file_operations and forget about dynamic
allocation, replace_fops, etc.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20250112080705.141166-3-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
Johannes Berg 67510d7e2e fs: debugfs: fix open proxy for unsafe files
In the previous commit referenced below, I had to split
the short fops handling into different proxy fops. This
necessitated knowing out-of-band whether or not the ops
are short or full, when attempting to convert from fops
to allocated fsdata.

Unfortunately, I only converted full_proxy_open() which
is used for the new full_proxy_open_regular() and
full_proxy_open_short(), but forgot about the call in
open_proxy_open(), used for debugfs_create_file_unsafe().

Fix that, it never has short fops.

Fixes: f8f25893a4 ("fs: debugfs: differentiate short fops with proxy ops")
Reported-by: Suresh Kumar Kurmi <suresh.kumar.kurmi@intel.com>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202501101055.bb8bf3e7-lkp@intel.com
Reported-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20250110085826.cd74f3b7a36b.I430c79c82ec3f954c2ff9665753bf6ac9e63eef8@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10 09:41:53 +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
Al Viro cb787f4ac0 [tree-wide] finally take no_llseek out
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")

To quote that commit,

  At -rc1 we'll need do a mechanical removal of no_llseek -

  git grep -l -w no_llseek | grep -v porting.rst | while read i; do
	sed -i '/\<no_llseek\>/d' $i
  done

  would do it.

Unfortunately, that hadn't been done.  Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
	.llseek = no_llseek,
so it's obviously safe.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-09-27 08:18:43 -07:00
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
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZpEGjAAKCRCRxhvAZXjc
 okXfAP4tFUYszUsSqYdsgy9UvXw3Dr5zOIzQmN++NdjGkbU5fgEAs2ystqEfJgr3
 v7XvGbu65CvL4/slNhBZOU4yekGx5Qc=
 =C4QD
 -----END PGP SIGNATURE-----

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
Rafael J. Wysocki 22349e79b9 Merge branches 'acpi-pm', 'acpi-video', 'acpi-apei' and 'acpi-extlog'
Merge an ACPI power management change, ACPI backlight driver changes, APEI
updates and ACPI extlog driver changes for 6.8-rc1:

 - Modify the ACPI LPIT table handling code to avoid u32 multiplication
   overflows in state residency computations (Nikita Kiryushin).

 - Drop an unused helper function from the ACPI backlight (video) driver
   and add a clarifying comment to it (Hans de Goede).

 - Update the ACPI backlight driver to avoid using uninitialized memory
   in some cases (Nikita Kiryushin).

 - Add ACPI backlight quirk for the Colorful X15 AT 23 laptop (Yuluo
   Qiu).

 - Add support for vendor-defined error types to the ACPI APEI error
   injection code (Avadhut Naik).

 - Adjust APEI to properly set MF_ACTION_REQUIRED on synchronous memory
   failure events, so they are handled differently from the asynchronous
   ones (Shuai Xue).

 - Fix NULL pointer dereference check in the ACPI extlog driver (Prarit
   Bhargava).

 - Adjust the ACPI extlog driver to clear the Extended Error Log status
   when RAS_CEC handled the error (Tony Luck).

* acpi-pm:
  ACPI: LPIT: Avoid u32 multiplication overflow

* acpi-video:
  ACPI: video: Add quirk for the Colorful X15 AT 23 Laptop
  ACPI: video: check for error while searching for backlight device parent
  ACPI: video: Drop should_check_lcd_flag()
  ACPI: video: Add comment about acpi_video_backlight_use_native() usage

* acpi-apei:
  ACPI: APEI: set memory failure flags as MF_ACTION_REQUIRED on synchronous events
  ACPI: APEI: EINJ: Add support for vendor defined error types
  platform/chrome: cros_ec_debugfs: Fix permissions for panicinfo
  fs: debugfs: Add write functionality to debugfs blobs
  ACPI: APEI: EINJ: Refactor available_error_type_show()

* acpi-extlog:
  ACPI: extlog: Clear Extended Error Log status when RAS_CEC handled the error
  ACPI: extlog: fix NULL pointer dereference check
2024-01-04 13:19:40 +01:00
Johannes Berg 159f5bdadc debugfs: initialize cancellations earlier
Tetsuo Handa pointed out that in the (now reverted)
lockdep commit I initialized the data too late. The
same is true for the cancellation data, it must be
initialized before the cmpxchg(), otherwise it may
be done twice and possibly even overwriting data in
there already when there's a race. Fix that, which
also requires destroying the mutex in case we lost
the race.

Fixes: 8c88a47435 ("debugfs: add API to allow debugfs operations cancellation")
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20231221150444.1e47a0377f80.If7e8ba721ba2956f12c6e8405e7d61e154aa7ae7@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-22 07:33:02 +01:00
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
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEpeA8sTs3M8SN2hR410qiO8sPaAAFAmVnUrkACgkQ10qiO8sP
 aACE4A/9EdhyexRlNKdF3yLh0Q4acuR8IlaLBNgGiQDFxx17djE04p2PTpwkxOyn
 0EPy8dKhhWwoAkbvZ+6ToNFa+Jv9w+C5xVls2osGRuYGSVNlxCNy+8tWSNVT73jp
 rrapEkYHzuz9wBZiJpKwC+mK9uH9gAQgWyYUaTTeOnO/+m3HVhZdU6y71j8gQlm6
 9YFSI3r/VWlq1JpThn8WGULJXOMICWN0Sp4XRhEzHPLjK7MiCLNrrQSyV+uMHHUI
 PmRQN8QW6Oomjbcih3YNn+Geps7xUJFEG4mZvM6GUBXugnIq9t9xmzEbEJyBRIpl
 MGTwrIAyxtvBeHMpB7U/R3RSEyHfSW6fXHgN2S8ZEFTu6v70gP3TK8lL1gWc5mR4
 GogNaGQ0G6LdiHjM7XeGUv/SfzD6HJWa9aR1JbRwapkvxFfM7BEc14gxip0nFDLG
 z9sixiztGmzBsxmDc+h7M6YLlvWe4oqueUyjA7/p42NhYq41Zy/BYK5oUgsuL4ah
 Lsb00O6Mz9m6iPtJlREe81Qsclkjg8xMY2YcCYELXP3v50KwU3THBAOYbh5hvgrL
 T2gibkR0zFAGz1EDcPyQq/SBeUtASPVHyLGUMae6DOcVnOFdAhDTbX0B/TvcnRSq
 e1gvmNywL7wFVZLD/RYZtWW9g6NUcwK+CU59PRBh2OqVb0ow8Ls=
 =X6t2
 -----END PGP SIGNATURE-----

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
Avadhut Naik 71cd3c6364 fs: debugfs: Add write functionality to debugfs blobs
Currently, debugfs_create_blob() creates read-only debugfs binary blob
files.

In some cases, however, userspace tools need to write variable length
data structures into predetermined memory addresses. An example is when
injecting Vendor-defined error types through the einj module. In such
cases, the functionality to write to these blob files in debugfs would
be desired since the mapping aspect can be handled within the modules
with userspace tools only needing to write into the blob files.

Implement a write callback to enable writing to these blob files, created
in debugfs, by owners only.

Signed-off-by: Avadhut Naik <Avadhut.Naik@amd.com>
Reviewed-by: Alexey Kardashevskiy <aik@amd.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-11-21 21:10:44 +01:00
Linus Torvalds b06f58ad8e Driver core changes for 6.7-rc1
Here is the set of driver core updates for 6.7-rc1.  Nothing major in
 here at all, just a small number of changes including:
   - minor cleanups and updates from Andy Shevchenko
   - __counted_by addition
   - firmware_loader update for aborting loads cleaner
   - other minor changes, details in the shortlog
   - documentation update
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCZUTe8A8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ynP0QCfT2jQx3OcL22MoqCvdTuZJKPiHSIAoMxrliJF
 d4cUeICW17ywlTFzsKg8
 =nTeu
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the set of driver core updates for 6.7-rc1. Nothing major in
  here at all, just a small number of changes including:

   - minor cleanups and updates from Andy Shevchenko

   - __counted_by addition

   - firmware_loader update for aborting loads cleaner

   - other minor changes, details in the shortlog

   - documentation update

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

* tag 'driver-core-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (21 commits)
  firmware_loader: Abort all upcoming firmware load request once reboot triggered
  firmware_loader: Refactor kill_pending_fw_fallback_reqs()
  Documentation: security-bugs.rst: linux-distros relaxed their rules
  driver core: Release all resources during unbind before updating device links
  driver core: class: remove boilerplate code
  driver core: platform: Annotate struct irq_affinity_devres with __counted_by
  resource: Constify resource crosscheck APIs
  resource: Unify next_resource() and next_resource_skip_children()
  resource: Reuse for_each_resource() macro
  PCI: Implement custom llseek for sysfs resource entries
  kernfs: sysfs: support custom llseek method for sysfs entries
  debugfs: Fix __rcu type comparison warning
  device property: Replace custom implementation of COUNT_ARGS()
  drivers: base: test: Make property entry API test modular
  driver core: Add missing parameter description to __fwnode_link_add()
  device property: Clarify usage scope of some struct fwnode_handle members
  devres: rename the first parameter of devm_add_action(_or_reset)
  driver core: platform: Unify the firmware node type check
  driver core: platform: Use temporary variable in platform_device_add()
  driver core: platform: Refactor error path in a couple places
  ...
2023-11-03 15:15:47 -10:00
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
Mike Tipton 7360a48bd0 debugfs: Fix __rcu type comparison warning
Sparse reports the following:

fs/debugfs/file.c:942:9: sparse: sparse: incompatible types in comparison expression (different address spaces):
fs/debugfs/file.c:942:9: sparse:    char [noderef] __rcu *
fs/debugfs/file.c:942:9: sparse:    char *

rcu_assign_pointer() expects that it's assigning to pointers annotated
with __rcu. We can't annotate the generic struct file::private_data, so
cast it instead.

Fixes: 86b5488121 ("debugfs: Add write support to debugfs_create_str()")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309091933.BRWlSnCq-lkp@intel.com/
Signed-off-by: Mike Tipton <quic_mdtipton@quicinc.com>
Link: https://lore.kernel.org/r/20230922134512.5126-1-quic_mdtipton@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-05 13:18:18 +02:00
Linus Torvalds 1c9f8dff62 Char/Misc driver changes for 6.6-rc1
Here is the big set of char/misc and other small driver subsystem
 changes for 6.6-rc1.
 
 Stuff all over the place here, lots of driver updates and changes and
 new additions.  Short summary is:
   - new IIO drivers and updates
   - Interconnect driver updates
   - fpga driver updates and additions
   - fsi driver updates
   - mei driver updates
   - coresight driver updates
   - nvmem driver updates
   - counter driver updates
   - lots of smaller misc and char driver updates and additions
 
 All of these have been in linux-next for a long time with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCZPH64g8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ynr2QCfd3RKeR+WnGzyEOFhksl30UJJhiIAoNZtYT5+
 t9KG0iMDXRuTsOqeEQbd
 =tVnk
 -----END PGP SIGNATURE-----

Merge tag 'char-misc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char/misc and other small driver subsystem
  changes for 6.6-rc1.

  Stuff all over the place here, lots of driver updates and changes and
  new additions. Short summary is:

   - new IIO drivers and updates

   - Interconnect driver updates

   - fpga driver updates and additions

   - fsi driver updates

   - mei driver updates

   - coresight driver updates

   - nvmem driver updates

   - counter driver updates

   - lots of smaller misc and char driver updates and additions

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

* tag 'char-misc-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (267 commits)
  nvmem: core: Notify when a new layout is registered
  nvmem: core: Do not open-code existing functions
  nvmem: core: Return NULL when no nvmem layout is found
  nvmem: core: Create all cells before adding the nvmem device
  nvmem: u-boot-env:: Replace zero-length array with DECLARE_FLEX_ARRAY() helper
  nvmem: sec-qfprom: Add Qualcomm secure QFPROM support
  dt-bindings: nvmem: sec-qfprom: Add bindings for secure qfprom
  dt-bindings: nvmem: Add compatible for QCM2290
  nvmem: Kconfig: Fix typo "drive" -> "driver"
  nvmem: Explicitly include correct DT includes
  nvmem: add new NXP QorIQ eFuse driver
  dt-bindings: nvmem: Add t1023-sfp efuse support
  dt-bindings: nvmem: qfprom: Add compatible for MSM8226
  nvmem: uniphier: Use devm_platform_get_and_ioremap_resource()
  nvmem: qfprom: do some cleanup
  nvmem: stm32-romem: Use devm_platform_get_and_ioremap_resource()
  nvmem: rockchip-efuse: Use devm_platform_get_and_ioremap_resource()
  nvmem: meson-mx-efuse: Convert to devm_platform_ioremap_resource()
  nvmem: lpc18xx_otp: Convert to devm_platform_ioremap_resource()
  nvmem: brcm_nvram: Use devm_platform_get_and_ioremap_resource()
  ...
2023-09-01 09:53:54 -07:00
Mike Tipton 86b5488121 debugfs: Add write support to debugfs_create_str()
Currently, debugfs_create_str() only supports reading strings from
debugfs. Add support for writing them as well.

Based on original implementation by Peter Zijlstra [0]. Write support
was present in the initial patch version, but dropped in v2 due to lack
of users. We have a user now, so reintroduce it.

[0] https://lore.kernel.org/all/YF3Hv5zXb%2F6lauzs@hirez.programming.kicks-ass.net/

Signed-off-by: Mike Tipton <quic_mdtipton@quicinc.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20230807142914.12480-2-quic_mdtipton@quicinc.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>
2023-08-22 21:04:07 +03:00
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
Ivan Orlov 266bff7345 debugfs: Correct the 'debugfs_create_str' docs
The documentation of the 'debugfs_create_str' says that the function
returns a pointer to a dentry created, or an ERR_PTR in case of error.
Actually, this is not true: this function doesn't return anything at all.
Correct the documentation correspondingly.

Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Link: https://lore.kernel.org/r/20230514172353.52878-1-ivan.orlov0322@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-31 19:02:14 +01:00
Linus Torvalds 11c7052998 ARM: SoC drivers for 6.3
As usual, there are lots of minor driver changes across SoC platforms
 from  NXP, Amlogic, AMD Zynq, Mediatek, Qualcomm, Apple and Samsung.
 These usually add support for additional chip variations in existing
 drivers, but also add features or bugfixes.
 
 The SCMI firmware subsystem gains a unified raw userspace interface
 through debugfs, which can be used for validation purposes.
 
 Newly added drivers include:
 
  - New power management drivers for StarFive JH7110, Allwinner D1 and
    Renesas RZ/V2M
 
  - A driver for Qualcomm battery and power supply status
 
  - A SoC device driver for identifying Nuvoton WPCM450 chips
 
  - A regulator coupler driver for Mediatek MT81xxv
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEo6/YBQwIrVS28WGKmmx57+YAGNkFAmPtSN8ACgkQmmx57+YA
 GNkOSw/+JS5tElm/ZP7c3uWYp6uwvcb0jUlKW/U3aCtPiPEcYDLEqIEXwcNdaDMh
 m4rW3GYlW0IRL3FsyuYkSLx+EIIUIfs40wldYXJOqRDj0XasndiloIwltOQJGfd9
 C/UVM0FpJdxMJrcBMFgwLLQCIbAVnhHP34i6ppDRgxW/MfTeiCaaG6fnS70iv6mC
 oh2N7FoZSKDtTrFtlR5TqFiK5v/W1CgNJVuglkFB0ceFpjyBpp/8AT0FGS887xCz
 IYSTqm4Q/79vaZXI1Y2oog257cgdwsVqgPrnK5CuSFhTnAcJMCekiFelHq8Yhyuk
 Rw7j/B3KO3AOaxmR75c6SZdeZ+VHgUMRC/RKe3fay0sm3Zea2kAIPXA6Zn+r/cxb
 8M94V59qBz+f8XmpXRTK1UR3s3EbwFIuNyuDIkeorMtpSKtvqJXmZxGDwNIfXr2F
 /voo++MKjzdtdxdW/D/5Tc9DC0Pyb4HLi0EYj2QCzA03njmfLDF1w73NfzMec+GD
 R1zAd3FEbiJQx8Hin0PSPjYXpfMnkjkGAEcE9N9Ralg4ewNWAxfOFsAhHKTZNssL
 pitTAvHR/+dXtvkX7FUi2l/6fqn8nJUrg/xRazPPp3scRbpuk8m6P4MNr3/lsaHk
 HTQ/hYwDdecWLvKXjw5y9yIr3yhLmPPcloTVIIFFjsM0t8b+d9E=
 =p6Xp
 -----END PGP SIGNATURE-----

Merge tag 'soc-drivers-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM SoC driver updates from Arnd Bergmann:
 "As usual, there are lots of minor driver changes across SoC platforms
  from NXP, Amlogic, AMD Zynq, Mediatek, Qualcomm, Apple and Samsung.
  These usually add support for additional chip variations in existing
  drivers, but also add features or bugfixes.

  The SCMI firmware subsystem gains a unified raw userspace interface
  through debugfs, which can be used for validation purposes.

  Newly added drivers include:

   - New power management drivers for StarFive JH7110, Allwinner D1 and
     Renesas RZ/V2M

   - A driver for Qualcomm battery and power supply status

   - A SoC device driver for identifying Nuvoton WPCM450 chips

   - A regulator coupler driver for Mediatek MT81xxv"

* tag 'soc-drivers-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (165 commits)
  power: supply: Introduce Qualcomm PMIC GLINK power supply
  soc: apple: rtkit: Do not copy the reg state structure to the stack
  soc: sunxi: SUN20I_PPU should depend on PM
  memory: renesas-rpc-if: Remove redundant division of dummy
  soc: qcom: socinfo: Add IDs for IPQ5332 and its variant
  dt-bindings: arm: qcom,ids: Add IDs for IPQ5332 and its variant
  dt-bindings: power: qcom,rpmpd: add RPMH_REGULATOR_LEVEL_LOW_SVS_L1
  firmware: qcom_scm: Move qcom_scm.h to include/linux/firmware/qcom/
  MAINTAINERS: Update qcom CPR maintainer entry
  dt-bindings: firmware: document Qualcomm SM8550 SCM
  dt-bindings: firmware: qcom,scm: add qcom,scm-sa8775p compatible
  soc: qcom: socinfo: Add Soc IDs for IPQ8064 and variants
  dt-bindings: arm: qcom,ids: Add Soc IDs for IPQ8064 and variants
  soc: qcom: socinfo: Add support for new field in revision 17
  soc: qcom: smd-rpm: Add IPQ9574 compatible
  soc: qcom: pmic_glink: remove redundant calculation of svid
  soc: qcom: stats: Populate all subsystem debugfs files
  dt-bindings: soc: qcom,rpmh-rsc: Update to allow for generic nodes
  soc: qcom: pmic_glink: add CONFIG_NET/CONFIG_OF dependencies
  soc: qcom: pmic_glink: Introduce altmode support
  ...
2023-02-27 10:04:49 -08:00