linux-stable.git/fs/stat.c, branch v6.11

Merge tag 'for-6.11/block-20240710' of git://git.kernel.dk/linux

2024-07-15T21:20:22+00:00

Pull block updates from Jens Axboe:

 - NVMe updates via Keith:
     - Device initialization memory leak fixes (Keith)
     - More constants defined (Weiwen)
     - Target debugfs support (Hannes)
     - PCIe subsystem reset enhancements (Keith)
     - Queue-depth multipath policy (Redhat and PureStorage)
     - Implement get_unique_id (Christoph)
     - Authentication error fixes (Gaosheng)

 - MD updates via Song
     - sync_action fix and refactoring (Yu Kuai)
     - Various small fixes (Christoph Hellwig, Li Nan, and Ofir Gal, Yu
       Kuai, Benjamin Marzinski, Christophe JAILLET, Yang Li)

 - Fix loop detach/open race (Gulam)

 - Fix lower control limit for blk-throttle (Yu)

 - Add module descriptions to various drivers (Jeff)

 - Add support for atomic writes for block devices, and statx reporting
   for same. Includes SCSI and NVMe (John, Prasad, Alan)

 - Add IO priority information to block trace points (Dongliang)

 - Various zone improvements and tweaks (Damien)

 - mq-deadline tag reservation improvements (Bart)

 - Ignore direct reclaim swap writes in writeback throttling (Baokun)

 - Block integrity improvements and fixes (Anuj)

 - Add basic support for rust based block drivers. Has a dummy null_blk
   variant for now (Andreas)

 - Series converting driver settings to queue limits, and cleanups and
   fixes related to that (Christoph)

 - Cleanup for poking too deeply into the bvec internals, in preparation
   for DMA mapping API changes (Christoph)

 - Various minor tweaks and fixes (Jiapeng, John, Kanchan, Mikulas,
   Ming, Zhu, Damien, Christophe, Chaitanya)

* tag 'for-6.11/block-20240710' of git://git.kernel.dk/linux: (206 commits)
  floppy: add missing MODULE_DESCRIPTION() macro
  loop: add missing MODULE_DESCRIPTION() macro
  ublk_drv: add missing MODULE_DESCRIPTION() macro
  xen/blkback: add missing MODULE_DESCRIPTION() macro
  block/rnbd: Constify struct kobj_type
  block: take offset into account in blk_bvec_map_sg again
  block: fix get_max_segment_size() warning
  loop: Don't bother validating blocksize
  virtio_blk: Don't bother validating blocksize
  null_blk: Don't bother validating blocksize
  block: Validate logical block size in blk_validate_limits()
  virtio_blk: Fix default logical block size fallback
  nvmet-auth: fix nvmet_auth hash error handling
  nvme: implement ->get_unique_id
  block: pass a phys_addr_t to get_max_segment_size
  block: add a bvec_phys helper
  blk-lib: check for kill signal in ioctl BLKZEROOUT
  block: limit the Write Zeroes to manually writing zeroes fallback
  block: refacto blkdev_issue_zeroout
  block: move read-only and supported checks into (__)blkdev_issue_zeroout
  ...

vfs: support statx(..., NULL, AT_EMPTY_PATH, ...)

2024-06-27T16:31:20+00:00

The newly used helper also checks for empty ("") paths.

NULL paths with any flag value other than AT_EMPTY_PATH go the usual
route and end up with -EFAULT to retain compatibility (Rust is abusing
calls of the sort to detect availability of statx).

This avoids path lookup code, lockref management, memory allocation and
in case of NULL path userspace memory access (which can be quite
expensive with SMAP on x86_64).

Benchmarked with statx(..., AT_EMPTY_PATH, ...) running on Sapphire
Rapids, with the "" path for the first two cases and NULL for the last
one.

Results in ops/s:
stock:     4231237
pre-check: 5944063 (+40%)
NULL path: 6601619 (+11%/+56%)

Signed-off-by: Mateusz Guzik 
Link: https://lore.kernel.org/r/20240625151807.620812-1-mjguzik@gmail.com
Tested-by: Xi Ruoyao 
[brauner: use path_mounted() and other tweaks]
Signed-off-by: Christian Brauner

stat: use vfs_empty_path() helper

2024-06-27T16:31:20+00:00

Use the newly added helper for this.

Signed-off-by: Christian Brauner

block: Add atomic write support for statx

2024-06-20T21:19:17+00:00

Extend statx system call to return additional info for atomic write support
support if the specified file is a block device.

Reviewed-by: Martin K. Petersen 
Signed-off-by: Prasad Singamsetty 
Signed-off-by: John Garry 
Reviewed-by: Keith Busch 
Acked-by: Darrick J. Wong 
Reviewed-by: Darrick J. Wong 
Reviewed-by: Luis Chamberlain 
Link: https://lore.kernel.org/r/20240620125359.2684798-7-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

fs: Add initial atomic write support info to statx

2024-06-20T21:19:17+00:00

Extend statx system call to return additional info for atomic write support
support for a file.

Helper function generic_fill_statx_atomic_writes() can be used by FSes to
fill in the relevant statx fields. For now atomic_write_segments_max will
always be 1, otherwise some rules would need to be imposed on iovec length
and alignment, which we don't want now.

Signed-off-by: Prasad Singamsetty 
jpg: relocate bdev support to another patch
Reviewed-by: Darrick J. Wong 
Reviewed-by: Martin K. Petersen 
Signed-off-by: John Garry 
Acked-by: Darrick J. Wong 
Link: https://lore.kernel.org/r/20240620125359.2684798-5-john.g.garry@oracle.com
Signed-off-by: Jens Axboe

vfs: retire user_path_at_empty and drop empty arg from getname_flags

2024-06-05T15:03:57+00:00

No users after do_readlinkat started doing the job on its own.

Signed-off-by: Mateusz Guzik 
Link: https://lore.kernel.org/r/20240604155257.109500-3-mjguzik@gmail.com
Reviewed-by: Jan Kara 
Signed-off-by: Christian Brauner

vfs: stop using user_path_at_empty in do_readlinkat

2024-06-05T15:03:56+00:00

It is the only consumer and it saddles getname_flags with an argument set
to NULL by everyone else.

Instead the routine can do the empty check on its own.

Then user_path_at_empty can get retired and getname_flags can lose the
argument.

Signed-off-by: Mateusz Guzik 
Link: https://lore.kernel.org/r/20240604155257.109500-2-mjguzik@gmail.com
Reviewed-by: Jan Kara 
Signed-off-by: Christian Brauner

statx: stx_subvol

2024-03-26T08:01:18+00:00

Add a new statx field for (sub)volume identifiers, as implemented by
btrfs and bcachefs.

This includes bcachefs support; we'll definitely want btrfs support as
well.

Link: https://lore.kernel.org/linux-fsdevel/2uvhm6gweyl7iyyp2xpfryvcu2g3padagaeqcbiavjyiis6prl@yjm725bizncq/
Signed-off-by: Kent Overstreet 
Cc: Josef Bacik 
Cc: Miklos Szeredi 
Cc: Christian Brauner 
Cc: David Howells 
Signed-off-by: Kent Overstreet 
Link: https://lore.kernel.org/r/20240308022914.196982-1-kent.overstreet@linux.dev
Signed-off-by: Johannes Thumshirn 
Signed-off-by: Christian Brauner

Merge tag 'vfs-6.8.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2024-01-08T18:57:34+00:00

Pull vfs mount updates from Christian Brauner:
 "This contains the work to retrieve detailed information about mounts
  via two new system calls. This is hopefully the beginning of the end
  of the saga that started with fsinfo() years ago.

  The LWN articles in [1] and [2] can serve as a summary so we can avoid
  rehashing everything here.

  At LSFMM in May 2022 we got into a room and agreed on what we want to
  do about fsinfo(). Basically, split it into pieces. This is the first
  part of that agreement. Specifically, it is concerned with retrieving
  information about mounts. So this only concerns the mount information
  retrieval, not the mount table change notification, or the extended
  filesystem specific mount option work. That is separate work.

  Currently mounts have a 32bit id. Mount ids are already in heavy use
  by libmount and other low-level userspace but they can't be relied
  upon because they're recycled very quickly. We agreed that mounts
  should carry a unique 64bit id by which they can be referenced
  directly. This is now implemented as part of this work.

  The new 64bit mount id is exposed in statx() through the new
  STATX_MNT_ID_UNIQUE flag. If the flag isn't raised the old mount id is
  returned. If it is raised and the kernel supports the new 64bit mount
  id the flag is raised in the result mask and the new 64bit mount id is
  returned. New and old mount ids do not overlap so they cannot be
  conflated.

  Two new system calls are introduced that operate on the 64bit mount
  id: statmount() and listmount(). A summary of the api and usage can be
  found on LWN as well (cf. [3]) but of course, I'll provide a summary
  here as well.

  Both system calls rely on struct mnt_id_req. Which is the request
  struct used to pass the 64bit mount id identifying the mount to
  operate on. It is extensible to allow for the addition of new
  parameters and for future use in other apis that make use of mount
  ids.

  statmount() mimicks the semantics of statx() and exposes a set flags
  that userspace may raise in mnt_id_req to request specific information
  to be retrieved. A statmount() call returns a struct statmount filled
  in with information about the requested mount. Supported requests are
  indicated by raising the request flag passed in struct mnt_id_req in
  the @mask argument in struct statmount.

  Currently we do support:

   - STATMOUNT_SB_BASIC:
     Basic filesystem info

   - STATMOUNT_MNT_BASIC
     Mount information (mount id, parent mount id, mount attributes etc)

   - STATMOUNT_PROPAGATE_FROM
     Propagation from what mount in current namespace

   - STATMOUNT_MNT_ROOT
     Path of the root of the mount (e.g., mount --bind /bla /mnt returns /bla)

   - STATMOUNT_MNT_POINT
     Path of the mount point (e.g., mount --bind /bla /mnt returns /mnt)

   - STATMOUNT_FS_TYPE
     Name of the filesystem type as the magic number isn't enough due to submounts

  The string options STATMOUNT_MNT_{ROOT,POINT} and STATMOUNT_FS_TYPE
  are appended to the end of the struct. Userspace can use the offsets
  in @fs_type, @mnt_root, and @mnt_point to reference those strings
  easily.

  The struct statmount reserves quite a bit of space currently for
  future extensibility. This isn't really a problem and if this bothers
  us we can just send a follow-up pull request during this cycle.

  listmount() is given a 64bit mount id via mnt_id_req just as
  statmount(). It takes a buffer and a size to return an array of the
  64bit ids of the child mounts of the requested mount. Userspace can
  thus choose to either retrieve child mounts for a mount in batches or
  iterate through the child mounts. For most use-cases it will be
  sufficient to just leave space for a few child mounts. But for big
  mount tables having an iterator is really helpful. Iterating through a
  mount table works by setting @param in mnt_id_req to the mount id of
  the last child mount retrieved in the previous listmount() call"

Link: https://lwn.net/Articles/934469 [1]
Link: https://lwn.net/Articles/829212 [2]
Link: https://lwn.net/Articles/950569 [3]

* tag 'vfs-6.8.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  add selftest for statmount/listmount
  fs: keep struct mnt_id_req extensible
  wire up syscalls for statmount/listmount
  add listmount(2) syscall
  statmount: simplify string option retrieval
  statmount: simplify numeric option retrieval
  add statmount(2) syscall
  namespace: extract show_path() helper
  mounts: keep list of mounts in an rbtree
  add unique mount ID

Merge tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2024-01-08T18:26:08+00:00

Pull misc vfs updates from Christian Brauner:
 "This contains the usual miscellaneous features, cleanups, and fixes
  for vfs and individual fses.

  Features:

   - Add Jan Kara as VFS reviewer

   - Show correct device and inode numbers in proc//maps for vma
     files on stacked filesystems. This is now easily doable thanks to
     the backing file work from the last cycles. This comes with
     selftests

  Cleanups:

   - Remove a redundant might_sleep() from wait_on_inode()

   - Initialize pointer with NULL, not 0

   - Clarify comment on access_override_creds()

   - Rework and simplify eventfd_signal() and eventfd_signal_mask()
     helpers

   - Process aio completions in batches to avoid needless wakeups

   - Completely decouple struct mnt_idmap from namespaces. We now only
     keep the actual idmapping around and don't stash references to
     namespaces

   - Reformat maintainer entries to indicate that a given subsystem
     belongs to fs/

   - Simplify fput() for files that were never opened

   - Get rid of various pointless file helpers

   - Rename various file helpers

   - Rename struct file members after SLAB_TYPESAFE_BY_RCU switch from
     last cycle

   - Make relatime_need_update() return bool

   - Use GFP_KERNEL instead of GFP_USER when allocating superblocks

   - Replace deprecated ida_simple_*() calls with their current ida_*()
     counterparts

  Fixes:

   - Fix comments on user namespace id mapping helpers. They aren't
     kernel doc comments so they shouldn't be using /**

   - s/Retuns/Returns/g in various places

   - Add missing parameter documentation on can_move_mount_beneath()

   - Rename i_mapping->private_data to i_mapping->i_private_data

   - Fix a false-positive lockdep warning in pipe_write() for watch
     queues

   - Improve __fget_files_rcu() code generation to improve performance

   - Only notify writer that pipe resizing has finished after setting
     pipe->max_usage otherwise writers are never notified that the pipe
     has been resized and hang

   - Fix some kernel docs in hfsplus

   - s/passs/pass/g in various places

   - Fix kernel docs in ntfs

   - Fix kcalloc() arguments order reported by gcc 14

   - Fix uninitialized value in reiserfs"

* tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (36 commits)
  reiserfs: fix uninit-value in comp_keys
  watch_queue: fix kcalloc() arguments order
  ntfs: dir.c: fix kernel-doc function parameter warnings
  fs: fix doc comment typo fs tree wide
  selftests/overlayfs: verify device and inode numbers in /proc/pid/maps
  fs/proc: show correct device and inode numbers in /proc/pid/maps
  eventfd: Remove usage of the deprecated ida_simple_xx() API
  fs: super: use GFP_KERNEL instead of GFP_USER for super block allocation
  fs/hfsplus: wrapper.c: fix kernel-doc warnings
  fs: add Jan Kara as reviewer
  fs/inode: Make relatime_need_update return bool
  pipe: wakeup wr_wait after setting max_usage
  file: remove __receive_fd()
  file: stop exposing receive_fd_user()
  fs: replace f_rcuhead with f_task_work
  file: remove pointless wrapper
  file: s/close_fd_get_file()/file_close_fd()/g
  Improve __fget_files_rcu() code generation (and thus __fget_light())
  file: massage cleanup of files that failed to open
  fs/pipe: Fix lockdep false-positive in watchqueue pipe_write()
  ...