Eric Lee / smarc-fsl-linux-kernel

27 Oct, 2020

1 commit

26 Oct, 2020

1 commit

24 Oct, 2020

1 commit

  • c4728cfbe   Merge tag 'vfs-5.10-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux ... Browse Code »

    Pull clone/dedupe/remap code refactoring from Darrick Wong:
    "Move the generic file range remap (aka reflink and dedupe) functions
    out of mm/filemap.c and fs/read_write.c and into fs/remap_range.c to
    reduce clutter in the first two files"

    * tag 'vfs-5.10-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
    vfs: move the generic write and copy checks out of mm
    vfs: move the remap range helpers to remap_range.c
    vfs: move generic_remap_checks out of mm

    Linus Torvalds
     

23 Oct, 2020

1 commit

16 Oct, 2020

1 commit

  • 726eb70e0   Merge tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc ... Browse Code »

    Pull char/misc driver updates from Greg KH:
    "Here is the big set of char, misc, and other assorted driver subsystem
    patches for 5.10-rc1.

    There's a lot of different things in here, all over the drivers/
    directory. Some summaries:

    - soundwire driver updates

    - habanalabs driver updates

    - extcon driver updates

    - nitro_enclaves new driver

    - fsl-mc driver and core updates

    - mhi core and bus updates

    - nvmem driver updates

    - eeprom driver updates

    - binder driver updates and fixes

    - vbox minor bugfixes

    - fsi driver updates

    - w1 driver updates

    - coresight driver updates

    - interconnect driver updates

    - misc driver updates

    - other minor driver updates

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

    * tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (396 commits)
    binder: fix UAF when releasing todo list
    docs: w1: w1_therm: Fix broken xref, mistakes, clarify text
    misc: Kconfig: fix a HISI_HIKEY_USB dependency
    LSM: Fix type of id parameter in kernel_post_load_data prototype
    misc: Kconfig: add a new dependency for HISI_HIKEY_USB
    firmware_loader: fix a kernel-doc markup
    w1: w1_therm: make w1_poll_completion static
    binder: simplify the return expression of binder_mmap
    test_firmware: Test partial read support
    firmware: Add request_partial_firmware_into_buf()
    firmware: Store opt_flags in fw_priv
    fs/kernel_file_read: Add "offset" arg for partial reads
    IMA: Add support for file reads without contents
    LSM: Add "contents" flag to kernel_read_file hook
    module: Call security_kernel_post_load_data()
    firmware_loader: Use security_post_load_data()
    LSM: Introduce kernel_post_load_data() hook
    fs/kernel_read_file: Add file_size output argument
    fs/kernel_read_file: Switch buffer size arg to size_t
    fs/kernel_read_file: Remove redundant size argument
    ...

    Linus Torvalds
     

15 Oct, 2020

1 commit

  • 02e83f46e   vfs: move generic_remap_checks out of mm ... Browse Code »

    I would like to move all the generic helpers for the vfs remap range
    functionality (aka clonerange and dedupe) into a separate file so that
    they won't be scattered across the vfs and the mm subsystems. The
    eventual goal is to be able to deselect remap_range.c if none of the
    filesystems need that code, but the tricky part here is picking a
    stable(ish) part of the merge window to rearrange code.

    Signed-off-by: Darrick J. Wong

    Darrick J. Wong
     

05 Oct, 2020

1 commit

  • 5287b07f6   fs/kernel_read_file: Split into separate source file ... Browse Code »

    These routines are used in places outside of exec(2), so in preparation
    for refactoring them, move them into a separate source file,
    fs/kernel_read_file.c.

    Signed-off-by: Kees Cook
    Reviewed-by: Mimi Zohar
    Reviewed-by: Luis Chamberlain
    Acked-by: Scott Branden
    Link: https://lore.kernel.org/r/20201002173828.2099543-5-keescook@chromium.org
    Signed-off-by: Greg Kroah-Hartman

    Kees Cook
     

23 Sep, 2020

1 commit

08 Aug, 2020

1 commit

31 Jul, 2020

1 commit

  • c60166f04   init: add an init_mount helper ... Browse Code »

    Like do_mount, but takes a kernel pointer for the destination path.
    Switch over the mounts in the init code and devtmpfs to it, which
    just happen to work due to the implicit set_fs(KERNEL_DS) during early
    init right now.

    Signed-off-by: Christoph Hellwig

    Christoph Hellwig
     

29 May, 2020

1 commit

09 Apr, 2020

1 commit

06 Mar, 2020

1 commit

11 Feb, 2020

1 commit

10 Feb, 2020

2 commits

  • 380a129eb   Merge tag 'zonefs-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs ... Browse Code »

    Pull new zonefs file system from Damien Le Moal:
    "Zonefs is a very simple file system exposing each zone of a zoned
    block device as a file.

    Unlike a regular file system with native zoned block device support
    (e.g. f2fs or the on-going btrfs effort), zonefs does not hide the
    sequential write constraint of zoned block devices to the user. As a
    result, zonefs is not a POSIX compliant file system. Its goal is to
    simplify the implementation of zoned block devices support in
    applications by replacing raw block device file accesses with a richer
    file based API, avoiding relying on direct block device file ioctls
    which may be more obscure to developers.

    One example of this approach is the implementation of LSM
    (log-structured merge) tree structures (such as used in RocksDB and
    LevelDB) on zoned block devices by allowing SSTables to be stored in a
    zone file similarly to a regular file system rather than as a range of
    sectors of a zoned device. The introduction of the higher level
    construct "one file is one zone" can help reducing the amount of
    changes needed in the application while at the same time allowing the
    use of zoned block devices with various programming languages other
    than C.

    Zonefs IO management implementation uses the new iomap generic code.
    Zonefs has been successfully tested using a functional test suite
    (available with zonefs userland format tool on github) and a prototype
    implementation of LevelDB on top of zonefs"

    * tag 'zonefs-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
    zonefs: Add documentation
    fs: New zonefs file system

    Linus Torvalds
     
  • 5586c3c1e   Merge branch 'work.vboxsf' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs ... Browse Code »

    Pull vboxfs from Al Viro:
    "This is the VirtualBox guest shared folder support by Hans de Goede,
    with fixups for fs_parse folded in to avoid bisection hazards from
    those API changes..."

    * 'work.vboxsf' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
    fs: Add VirtualBox guest shared folder (vboxsf) support

    Linus Torvalds
     

09 Feb, 2020

1 commit

  • 0fd169576   fs: Add VirtualBox guest shared folder (vboxsf) support ... Browse Code »

    VirtualBox hosts can share folders with guests, this commit adds a
    VFS driver implementing the Linux-guest side of this, allowing folders
    exported by the host to be mounted under Linux.

    This driver depends on the guest host IPC functions exported by
    the vboxguest driver.

    Acked-by: Christoph Hellwig
    Signed-off-by: Hans de Goede
    Signed-off-by: Al Viro

    Hans de Goede
     

07 Feb, 2020

1 commit

  • 8dcc1a9d9   fs: New zonefs file system ... Browse Code »

    zonefs is a very simple file system exposing each zone of a zoned block
    device as a file. Unlike a regular file system with zoned block device
    support (e.g. f2fs), zonefs does not hide the sequential write
    constraint of zoned block devices to the user. Files representing
    sequential write zones of the device must be written sequentially
    starting from the end of the file (append only writes).

    As such, zonefs is in essence closer to a raw block device access
    interface than to a full featured POSIX file system. The goal of zonefs
    is to simplify the implementation of zoned block device support in
    applications by replacing raw block device file accesses with a richer
    file API, avoiding relying on direct block device file ioctls which may
    be more obscure to developers. One example of this approach is the
    implementation of LSM (log-structured merge) tree structures (such as
    used in RocksDB and LevelDB) on zoned block devices by allowing SSTables
    to be stored in a zone file similarly to a regular file system rather
    than as a range of sectors of a zoned device. The introduction of the
    higher level construct "one file is one zone" can help reducing the
    amount of changes needed in the application as well as introducing
    support for different application programming languages.

    Zonefs on-disk metadata is reduced to an immutable super block to
    persistently store a magic number and optional feature flags and
    values. On mount, zonefs uses blkdev_report_zones() to obtain the device
    zone configuration and populates the mount point with a static file tree
    solely based on this information. E.g. file sizes come from the device
    zone type and write pointer offset managed by the device itself.

    The zone files created on mount have the following characteristics.
    1) Files representing zones of the same type are grouped together
    under a common sub-directory:
    * For conventional zones, the sub-directory "cnv" is used.
    * For sequential write zones, the sub-directory "seq" is used.
    These two directories are the only directories that exist in zonefs.
    Users cannot create other directories and cannot rename nor delete
    the "cnv" and "seq" sub-directories.
    2) The name of zone files is the number of the file within the zone
    type sub-directory, in order of increasing zone start sector.
    3) The size of conventional zone files is fixed to the device zone size.
    Conventional zone files cannot be truncated.
    4) The size of sequential zone files represent the file's zone write
    pointer position relative to the zone start sector. Truncating these
    files is allowed only down to 0, in which case, the zone is reset to
    rewind the zone write pointer position to the start of the zone, or
    up to the zone size, in which case the file's zone is transitioned
    to the FULL state (finish zone operation).
    5) All read and write operations to files are not allowed beyond the
    file zone size. Any access exceeding the zone size is failed with
    the -EFBIG error.
    6) Creating, deleting, renaming or modifying any attribute of files and
    sub-directories is not allowed.
    7) There are no restrictions on the type of read and write operations
    that can be issued to conventional zone files. Buffered, direct and
    mmap read & write operations are accepted. For sequential zone files,
    there are no restrictions on read operations, but all write
    operations must be direct IO append writes. mmap write of sequential
    files is not allowed.

    Several optional features of zonefs can be enabled at format time.
    * Conventional zone aggregation: ranges of contiguous conventional
    zones can be aggregated into a single larger file instead of the
    default one file per zone.
    * File ownership: The owner UID and GID of zone files is by default 0
    (root) but can be changed to any valid UID/GID.
    * File access permissions: the default 640 access permissions can be
    changed.

    The mkzonefs tool is used to format zoned block devices for use with
    zonefs. This tool is available on Github at:

    git@github.com:damien-lemoal/zonefs-tools.git.

    zonefs-tools also includes a test suite which can be run against any
    zoned block device, including null_blk block device created with zoned
    mode.

    Example: the following formats a 15TB host-managed SMR HDD with 256 MB
    zones with the conventional zones aggregation feature enabled.

    $ sudo mkzonefs -o aggr_cnv /dev/sdX
    $ sudo mount -t zonefs /dev/sdX /mnt
    $ ls -l /mnt/
    total 0
    dr-xr-xr-x 2 root root 1 Nov 25 13:23 cnv
    dr-xr-xr-x 2 root root 55356 Nov 25 13:23 seq

    The size of the zone files sub-directories indicate the number of files
    existing for each type of zones. In this example, there is only one
    conventional zone file (all conventional zones are aggregated under a
    single file).

    $ ls -l /mnt/cnv
    total 137101312
    -rw-r----- 1 root root 140391743488 Nov 25 13:23 0

    This aggregated conventional zone file can be used as a regular file.

    $ sudo mkfs.ext4 /mnt/cnv/0
    $ sudo mount -o loop /mnt/cnv/0 /data

    The "seq" sub-directory grouping files for sequential write zones has
    in this example 55356 zones.

    $ ls -lv /mnt/seq
    total 14511243264
    -rw-r----- 1 root root 0 Nov 25 13:23 0
    -rw-r----- 1 root root 0 Nov 25 13:23 1
    -rw-r----- 1 root root 0 Nov 25 13:23 2
    ...
    -rw-r----- 1 root root 0 Nov 25 13:23 55354
    -rw-r----- 1 root root 0 Nov 25 13:23 55355

    For sequential write zone files, the file size changes as data is
    appended at the end of the file, similarly to any regular file system.

    $ dd if=/dev/zero of=/mnt/seq/0 bs=4K count=1 conv=notrunc oflag=direct
    1+0 records in
    1+0 records out
    4096 bytes (4.1 kB, 4.0 KiB) copied, 0.000452219 s, 9.1 MB/s

    $ ls -l /mnt/seq/0
    -rw-r----- 1 root root 4096 Nov 25 13:23 /mnt/seq/0

    The written file can be truncated to the zone size, preventing any
    further write operation.

    $ truncate -s 268435456 /mnt/seq/0
    $ ls -l /mnt/seq/0
    -rw-r----- 1 root root 268435456 Nov 25 13:49 /mnt/seq/0

    Truncation to 0 size allows freeing the file zone storage space and
    restart append-writes to the file.

    $ truncate -s 0 /mnt/seq/0
    $ ls -l /mnt/seq/0
    -rw-r----- 1 root root 0 Nov 25 13:49 /mnt/seq/0

    Since files are statically mapped to zones on the disk, the number of
    blocks of a file as reported by stat() and fstat() indicates the size
    of the file zone.

    $ stat /mnt/seq/0
    File: /mnt/seq/0
    Size: 0 Blocks: 524288 IO Block: 4096 regular empty file
    Device: 870h/2160d Inode: 50431 Links: 1
    Access: (0640/-rw-r-----) Uid: ( 0/ root) Gid: ( 0/ root)
    Access: 2019-11-25 13:23:57.048971997 +0900
    Modify: 2019-11-25 13:52:25.553805765 +0900
    Change: 2019-11-25 13:52:25.553805765 +0900
    Birth: -

    The number of blocks of the file ("Blocks") in units of 512B blocks
    gives the maximum file size of 524288 * 512 B = 256 MB, corresponding
    to the device zone size in this example. Of note is that the "IO block"
    field always indicates the minimum IO size for writes and corresponds
    to the device physical sector size.

    This code contains contributions from:
    * Johannes Thumshirn ,
    * Darrick J. Wong ,
    * Christoph Hellwig ,
    * Chaitanya Kulkarni and
    * Ting Yao .

    Signed-off-by: Damien Le Moal
    Reviewed-by: Dave Chinner

    Damien Le Moal
     

04 Feb, 2020

1 commit

03 Feb, 2020

1 commit

03 Jan, 2020

1 commit

09 Dec, 2019

1 commit

30 Oct, 2019

1 commit

  • 771b53d03   io-wq: small threadpool implementation for io_uring ... Browse Code »

    This adds support for io-wq, a smaller and specialized thread pool
    implementation. This is meant to replace workqueues for io_uring. Among
    the reasons for this addition are:

    - We can assign memory context smarter and more persistently if we
    manage the life time of threads.

    - We can drop various work-arounds we have in io_uring, like the
    async_list.

    - We can implement hashed work insertion, to manage concurrency of
    buffered writes without needing a) an extra workqueue, or b)
    needlessly making the concurrency of said workqueue very low
    which hurts performance of multiple buffered file writers.

    - We can implement cancel through signals, for cancelling
    interruptible work like read/write (or send/recv) to/from sockets.

    - We need the above cancel for being able to assign and use file tables
    from a process.

    - We can implement a more thorough cancel operation in general.

    - We need it to move towards a syslet/threadlet model for even faster
    async execution. For that we need to take ownership of the used
    threads.

    This list is just off the top of my head. Performance should be the
    same, or better, at least that's what I've seen in my testing. io-wq
    supports basic NUMA functionality, setting up a pool per node.

    io-wq hooks up to the scheduler schedule in/out just like workqueue
    and uses that to drive the need for more/less workers.

    Acked-by: Peter Zijlstra (Intel)
    Signed-off-by: Jens Axboe

    Jens Axboe
     

21 Sep, 2019

1 commit

  • bfa0399bc   Merge Linus's 5.4-rc1-prerelease branch into android-mainline ... Browse Code »

    This merges Linus's tree as of commit b41dae061bbd ("Merge tag
    'xfs-5.4-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux")
    into android-mainline.

    This "early" merge makes it easier to test and handle merge conflicts
    instead of having to wait until the "end" of the merge window and handle
    all 10000+ commits at once.

    Signed-off-by: Greg Kroah-Hartman
    Change-Id: I6bebf55e5e2353f814e3c87f5033607b1ae5d812

    Greg Kroah-Hartman
     

19 Sep, 2019

1 commit

  • f60c55a94   Merge tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt ... Browse Code »

    Pull fs-verity support from Eric Biggers:
    "fs-verity is a filesystem feature that provides Merkle tree based
    hashing (similar to dm-verity) for individual readonly files, mainly
    for the purpose of efficient authenticity verification.

    This pull request includes:

    (a) The fs/verity/ support layer and documentation.

    (b) fs-verity support for ext4 and f2fs.

    Compared to the original fs-verity patchset from last year, the UAPI
    to enable fs-verity on a file has been greatly simplified. Lots of
    other things were cleaned up too.

    fs-verity is planned to be used by two different projects on Android;
    most of the userspace code is in place already. Another userspace tool
    ("fsverity-utils"), and xfstests, are also available. e2fsprogs and
    f2fs-tools already have fs-verity support. Other people have shown
    interest in using fs-verity too.

    I've tested this on ext4 and f2fs with xfstests, both the existing
    tests and the new fs-verity tests. This has also been in linux-next
    since July 30 with no reported issues except a couple minor ones I
    found myself and folded in fixes for.

    Ted and I will be co-maintaining fs-verity"

    * tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
    f2fs: add fs-verity support
    ext4: update on-disk format documentation for fs-verity
    ext4: add fs-verity read support
    ext4: add basic fs-verity support
    fs-verity: support builtin file signatures
    fs-verity: add SHA-512 support
    fs-verity: implement FS_IOC_MEASURE_VERITY ioctl
    fs-verity: implement FS_IOC_ENABLE_VERITY ioctl
    fs-verity: add data verification hooks for ->readpages()
    fs-verity: add the hook for file ->setattr()
    fs-verity: add the hook for file ->open()
    fs-verity: add inode and superblock fields
    fs-verity: add Kconfig and the helper functions for hashing
    fs: uapi: define verity bit for FS_IOC_GETFLAGS
    fs-verity: add UAPI header
    fs-verity: add MAINTAINERS file entry
    fs-verity: add a documentation file

    Linus Torvalds
     

24 Aug, 2019

1 commit

  • 47e4937a4   erofs: move erofs out of staging ... Browse Code »

    EROFS filesystem has been merged into linux-staging for a year.

    EROFS is designed to be a better solution of saving extra storage
    space with guaranteed end-to-end performance for read-only files
    with the help of reduced metadata, fixed-sized output compression
    and decompression inplace technologies.

    In the past year, EROFS was greatly improved by many people as
    a staging driver, self-tested, betaed by a large number of our
    internal users, successfully applied to almost all in-service
    HUAWEI smartphones as the part of EMUI 9.1 and proven to be stable
    enough to be moved out of staging.

    EROFS is a self-contained filesystem driver. Although there are
    still some TODOs to be more generic, we have a dedicated team
    actively keeping on working on EROFS in order to make it better
    with the evolution of Linux kernel as the other in-kernel filesystems.

    As Pavel suggested, it's better to do as one commit since git
    can do moves and all histories will be saved in this way.

    Let's promote it from staging and enhance it more actively as
    a "real" part of kernel for more wider scenarios!

    Cc: Greg Kroah-Hartman
    Cc: Alexander Viro
    Cc: Andrew Morton
    Cc: Stephen Rothwell
    Cc: Theodore Ts'o
    Cc: Pavel Machek
    Cc: David Sterba
    Cc: Amir Goldstein
    Cc: Christoph Hellwig
    Cc: Darrick J . Wong
    Cc: Dave Chinner
    Cc: Jaegeuk Kim
    Cc: Jan Kara
    Cc: Richard Weinberger
    Cc: Linus Torvalds
    Cc: Chao Yu
    Cc: Miao Xie
    Cc: Li Guifu
    Cc: Fang Wei
    Signed-off-by: Gao Xiang
    Link: https://lore.kernel.org/r/20190822213659.5501-1-hsiangkao@aol.com
    Signed-off-by: Greg Kroah-Hartman

    Gao Xiang
     

29 Jul, 2019

1 commit

24 Jul, 2019

1 commit

20 Jul, 2019

1 commit

  • bafafd366   ANDROID: sdcardfs: Add sdcardfs filesystem ... Browse Code »

    Bug: 11118565
    Bug: 27915347
    Bug: 27992761
    Bug: 28024488
    Bug: 30013843
    Bug: 30954918
    Bug: 34133558
    Bug: 34262585
    Bug: 34542611
    Bug: 34691169
    Bug: 34723223
    Bug: 35307857
    Bug: 35331000
    Bug: 35633782
    Bug: 35643557
    Bug: 35666680
    bug: 35766959
    Bug: 35766959
    Bug: 35848445
    Bug: 36004503
    Bug: 36007653
    Bug: 36138424
    Bug: 36160015
    Bug: 37193650
    Bug: 37231161
    Bug: 37488099
    Bug: 37516160
    Bug: 38045152
    Bug: 38117720
    Bug: 38502532
    Bug: 62390017
    Bug: 63245673
    Bug: 63260873
    Bug: 63785372
    Bug: 64672411
    Bug: 70278506
    Bug: 72007585
    Bug: 73055997
    Bug: 73287721
    Bug: 75987238
    Bug: 77923821
    Bug: 78262592
    Bug: 111641492
    Bug: 111642636
    Bug: 111860541
    Change-Id: Ic1e01e602ce335d97342be54f3da0c5c65c087cc
    Signed-off-by: Daniel Rosenberg
    [astrachan: Folded the following changes into this patch:
    903cea7ab0b2 ("ANDROID: Included sdcardfs source code for kernel 3.0")
    612a725e3d97 ("ANDROID: Port of sdcardfs to 4.4")
    e4187c55208b ("ANDROID: Changed type-casting in packagelist management")
    cf76072a5cd8 ("ANDROID: sdcardfs: Bring up to date with Android M permissions:")
    a43aa502c608 ("ANDROID: sdcardfs: Add support for d_canonical_path")
    d8fefbf85af2 ("ANDROID: sdcardfs: remove effectless config option")
    416677409336 ("ANDROID: sdcardfs: Remove unused code")
    8e49a570d351 ("ANDROID: sdcardfs: remove unneeded __init and __exit")
    40ee0e93f1d7 ("ANDROID: sdcardfs: Truncate packages_gid.list on overflow")
    b1d9602aa3fe ("ANDROID: sdcardfs: fix itnull.cocci warnings")
    60a177f5a167 ("ANDROID: sdcardfs: override umask on mkdir and create")
    efb3d2695203 ("ANDROID: sdcardfs: Check for other cases on path lookup")
    0da87f63666f ("ANDROID: sdcardfs: Fix locking for permission fix up")
    75b93060655e ("ANDROID: sdcardfs: Switch package list to RCU")
    657b0a00f497 ("ANDROID: sdcardfs: Added top to sdcardfs_inode_info")
    5008d91cba25 ("ANDROID: sdcardfs: fix external storage exporting incorrect uid")
    e06c452d0d07 ("ANDROID: sdcardfs: Move directory unlock before touch")
    72e5443a2816 ("ANDROID: sdcardfs: User new permission2 functions")
    ae8be7da556d ("ANDROID: sdcardfs: Add gid and mask to private mount data")
    151a3efe57a6 ("ANDROID: sdcardfs: Use per mount permissions")
    cff865a370f3 ("ANDROID: sdcardfs: Switch ->d_inode to d_inode()")
    065ac66804bf ("ANDROID: sdcardfs: Fix locking issue with permision fix up")
    31ea603eb3c4 ("ANDROID: sdcardfs: use wrappers to access i_mutex")
    c25c2f5018a2 ("ANDROID: sdcardfs: add parent pointer into dentry name hash")
    58616bb4ec68 ("ANDROID: sdcardfs: get rid of 'parent' argument of ->d_compare()")
    1654d7ffdd20 ("ANDROID: sdcardfs: Propagate dentry down to inode_change_ok()")
    39335cac1d2f ("ANDROID: sdcardfs: make it use new .rename i_op")
    7622bb3fcc79 ("ANDROID: sdcardfs: eliminate the offset argument to ->direct_IO")
    843bd7295ee0 ("ANDROID: sdcardfs: Allow non-owners to touch")
    e3d74804d174 ("ANDROID: sdcardfs: Refactor configfs interface")
    5833eda87a72 ("ANDROID: sdcardfs: add support for user permission isolation")
    d83fb1f41dd4 ("ANDROID: sdcardfs: Remove redundant operation")
    8767af17c0e5 ("ANDROID: sdcardfs: Add GID Derivation to sdcardfs")
    7119d96ad3ee ("ANDROID: sdcardfs: switch to full_name_hash and qstr")
    778e02a54859 ("ANDROID: sdcardfs: Switch strcasecmp for internal call")
    cd4965d04404 ("ANDROID: sdcardfs: Fix incorrect hash")
    40a2ee053505 ("ANDROID: sdcardfs: Add missing path_put")
    da5342bac57a ("ANDROID: sdcardfs: Don't bother deleting freelist")
    c91857b01e05 ("ANDROID: sdcardfs: implement vm_ops->page_mkwrite")
    f62b3906044b ("ANDROID: sdcardfs: support direct-IO (DIO) operations")
    c2e216d36d63 ("ANDROID: sdcardfs: Fix case insensitive lookup")
    57b92ab6f774 ("ANDROID: sdcardfs: rate limit warning print")
    8534cee39a81 ("ANDROID: sdcardfs: Replace get/put with d_lock")
    156085b2fccf ("ANDROID: sdcardfs: Use spin_lock_nested")
    8a260cabac4e ("ANDROID: sdcardfs: Switch to internal case insensitive compare")
    a8d51569573c ("ANDROID: sdcardfs: Use d_invalidate instead of drop_recurisve")
    932a6071de63 ("ANDROID: sdcardfs: Get the blocksize from the lower fs")
    0ad4c0f87527 ("ANDROID: sdcardfs: declare MODULE_ALIAS_FS")
    b97c83b5b683 ("ANDROID: sdcardfs: Use case insensitive hash function")
    9920dfb08265 ("ANDROID: sdcardfs: move path_put outside of spinlock")
    f9a25348b233 ("ANDROID: sdcardfs: Remove uninformative prints")
    720d9030bea1 ("ANDROID: sdcardfs: Fix gid issue")
    4cbb7fa6e66c ("ANDROID: sdcardfs: correct order of descriptors")
    6cff6cc301ed ("ANDROID: sdcardfs: Fix formatting")
    ac2a40412e26 ("ANDROID: sdcardfs: Fix style issues with comments")
    2212bb8ec064 ("ANDROID: sdcardfs: remove unneeded null check")
    4c1a0add8d21 ("ANDROID: sdcardfs: Use pr_[...] instead of printk")
    74535fe211ac ("ANDROID: sdcardfs: Use to kstrout")
    e6cf8dffd014 ("ANDROID: sdcardfs: Use seq_puts over seq_printf")
    2b1ac93a90b6 ("ANDROID: sdcardfs: Fix style issues in macros")
    bab6d117426f ("ANDROID: sdcardfs: remove unnecessary call to do_munmap")
    1c0bf09f19b6 ("ANDROID: sdcardfs: copy lower inode attributes in ->ioctl")
    42f3db55942b ("ANDROID: sdcardfs: fix ->llseek to update upper and lower offset")
    97ad6205055e ("ANDROID: sdcardfs: add read_iter/write_iter opeations")
    be9abc81332b ("ANDROID: sdcardfs: use d_splice_alias")
    4e90114cb1b4 ("ANDROID: sdcardfs: update module info")
    0e1f7ab14924 ("ANDROID: sdcardfs: Directly pass lower file for mmap")
    28be4beb43f9 ("ANDROID: sdcardfs: Change cache GID value")
    9fc2c452aefe ("ANDROID: sdcardfs: ->iget fixes")
    9bb72cf15cbc ("ANDROID: sdcardfs: Don't do d_add for lower fs")
    1bc21a04c11b ("ANDROID: sdcardfs: Don't complain in fixup_lower_ownership")
    0fb5b10b28a9 ("ANDROID: sdcardfs: Use filesystem specific hash")
    30e2f0aadce2 ("ANDROID: sdcardfs: Copy meta-data from lower inode")
    f748c7053194 ("ANDROID: sdcardfs: Avoid setting GIDs outside of valid ranges")
    3d38f08bacdb ("ANDROID: sdcardfs: Call lower fs's revalidate")
    2d1f1c203978 ("ANDROID: sdcardfs: Don't iput if we didn't igrab")
    857fc5e717fc ("ANDROID: sdcardfs: fix sdcardfs_destroy_inode for the inode RCU approach")
    4fceeccf1d23 ("ANDROID: sdcardfs: Move top to its own struct")
    f51470044a15 ("ANDROID: sdcardfs: Check for NULL in revalidate")
    8c7f6c97ac81 ("ANDROID: sdcardfs: d_splice_alias can return error values")
    17da01b37d61 ("ANDROID: sdcardfs: remove dead function open_flags_to_access_mode()")
    16662dd604be ("ANDROID: sdcardfs: use mount_nodev and fix a issue in sdcardfs_kill_sb")
    43c0dca6039a ("ANDROID: sdcardfs: Remove unnecessary lock")
    48960c25cdc1 ("ANDROID: sdcardfs: override credential for ioctl to lower fs")
    5d6410b9a88d ("ANDROID: Sdcardfs: Move gid derivation under flag")
    c7dd98431f83 ("ANDROID: sdcardfs: Add default_normal option")
    db9bf31a5d86 ("ANDROID: sdcardfs: port to 4.14")
    c70c9d1e82d2 ("ANDROID: sdcardfs: Use lower getattr times/size")
    04e961477d62 ("ANDROID: sdcardfs: Protect set_top")
    1ed04b79d281 ("ANDROID: sdcardfs: Hold i_mutex for i_size_write")
    77f52fc10982 ("ANDROID: sdcardfs: Set num in extension_details during make_item")
    d71596efa247 ("ANDROID: sdcardfs: fix lock issue on 32 bit/SMP architectures")
    ee6b07fced4a ("ANDROID: sdcardfs: Fix sdcardfs to stop creating cases-sensitive duplicate entries.")
    ce12807d5b75 ("ANDROID: sdcardfs: Check for private data earlier")
    c080450304cd ("ANDROID: sdcardfs: d_make_root calls iput")
    900e77796781 ("ANDROID: sdcardfs: Set s_root to NULL after putting")
    49092e89ffa4 ("ANDROID: sdcardfs: Don't d_drop in d_revalidate")
    e1f978bc9b9c ("ANDROID: sdcardfs: fix potential crash when reserved_mb is not zero")
    faa148eaf8ed ("ANDROID: sdcardfs: Check stacked filesystem depth")
    6edd721e972c ("ANDROID: sdcardfs: Don't use OVERRIDE_CRED macro")
    11ca578b4336 ("ANDROID: sdcardfs: Change current->fs under lock")
    83dea6ba6ea7 ("ANDROID: sdcardfs: Use inode iversion helpers")
    12064f3a794e ("ANDROID: sdcardfs: Add option to drop unused dentries")
    d9fe221bbf84 ("ANDROID: sdcardfs: Add sandbox")
    f544ad0b1547 ("ANDROID: sdcardfs: Add option to not link obb")]
    Signed-off-by: Alistair Strachan
    [drosen: folded in e6e368c99975 ("fs: sdcardfs: Add missing option to show_options")]

    Daniel Campello
     

17 Jul, 2019

1 commit

15 Jul, 2019

1 commit

08 May, 2019

1 commit

  • 5abe37954   Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 ... Browse Code »

    Pull ext4 updates from Ted Ts'o:
    "Add as a feature case-insensitive directories (the casefold feature)
    using Unicode 12.1.

    Also, the usual largish number of cleanups and bug fixes"

    * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (25 commits)
    ext4: export /sys/fs/ext4/feature/casefold if Unicode support is present
    ext4: fix ext4_show_options for file systems w/o journal
    unicode: refactor the rule for regenerating utf8data.h
    docs: ext4.rst: document case-insensitive directories
    ext4: Support case-insensitive file name lookups
    ext4: include charset encoding information in the superblock
    MAINTAINERS: add Unicode subsystem entry
    unicode: update unicode database unicode version 12.1.0
    unicode: introduce test module for normalized utf8 implementation
    unicode: implement higher level API for string handling
    unicode: reduce the size of utf8data[]
    unicode: introduce code for UTF-8 normalization
    unicode: introduce UTF-8 character database
    ext4: actually request zeroing of inode table after grow
    ext4: cond_resched in work-heavy group loops
    ext4: fix use-after-free race with debug_want_extra_isize
    ext4: avoid drop reference to iloc.bh twice
    ext4: ignore e_value_offs for xattrs with value-in-ea-inode
    ext4: protect journal inode's blocks using block_validity
    ext4: use BUG() instead of BUG_ON(1)
    ...

    Linus Torvalds
     

26 Apr, 2019

1 commit

  • 955405d11   unicode: introduce UTF-8 character database ... Browse Code »

    The decomposition and casefolding of UTF-8 characters are described in a
    prefix tree in utf8data.h, which is a generate from the Unicode
    Character Database (UCD), published by the Unicode Consortium, and
    should not be edited by hand. The structures in utf8data.h are meant to
    be used for lookup operations by the unicode subsystem, when decoding a
    utf-8 string.

    mkutf8data.c is the source for a program that generates utf8data.h. It
    was written by Olaf Weber from SGI and originally proposed to be merged
    into Linux in 2014. The original proposal performed the compatibility
    decomposition, NFKD, but the current version was modified by me to do
    canonical decomposition, NFD, as suggested by the community. The
    changes from the original submission are:

    * Rebase to mainline.
    * Fix out-of-tree-build.
    * Update makefile to build 11.0.0 ucd files.
    * drop references to xfs.
    * Convert NFKD to NFD.
    * Merge back robustness fixes from original patch. Requested by
    Dave Chinner.

    The original submission is archived at:

    The utf8data.h file can be regenerated using the instructions in
    fs/unicode/README.utf8data.

    - Notes on the update from 8.0.0 to 11.0:

    The structure of the ucd files and special cases have not experienced
    any changes between versions 8.0.0 and 11.0.0. 8.0.0 saw the addition
    of Cherokee LC characters, which is an interesting case for
    case-folding. The update is accompanied by new tests on the test_ucd
    module to catch specific cases. No changes to mkutf8data script were
    required for the updates.

    Signed-off-by: Gabriel Krisman Bertazi
    Signed-off-by: Theodore Ts'o

    Gabriel Krisman Bertazi
     

21 Mar, 2019

2 commits

  • 24dcb3d90   vfs: syscall: Add fsopen() to prepare for superblock creation ... Browse Code »

    Provide an fsopen() system call that starts the process of preparing to
    create a superblock that will then be mountable, using an fd as a context
    handle. fsopen() is given the name of the filesystem that will be used:

    int mfd = fsopen(const char *fsname, unsigned int flags);

    where flags can be 0 or FSOPEN_CLOEXEC.

    For example:

    sfd = fsopen("ext4", FSOPEN_CLOEXEC);
    fsconfig(sfd, FSCONFIG_SET_PATH, "source", "/dev/sda1", AT_FDCWD);
    fsconfig(sfd, FSCONFIG_SET_FLAG, "noatime", NULL, 0);
    fsconfig(sfd, FSCONFIG_SET_FLAG, "acl", NULL, 0);
    fsconfig(sfd, FSCONFIG_SET_FLAG, "user_xattr", NULL, 0);
    fsconfig(sfd, FSCONFIG_SET_STRING, "sb", "1", 0);
    fsconfig(sfd, FSCONFIG_CMD_CREATE, NULL, NULL, 0);
    fsinfo(sfd, NULL, ...); // query new superblock attributes
    mfd = fsmount(sfd, FSMOUNT_CLOEXEC, MS_RELATIME);
    move_mount(mfd, "", sfd, AT_FDCWD, "/mnt", MOVE_MOUNT_F_EMPTY_PATH);

    sfd = fsopen("afs", -1);
    fsconfig(fd, FSCONFIG_SET_STRING, "source",
    "#grand.central.org:root.cell", 0);
    fsconfig(fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0);
    mfd = fsmount(sfd, 0, MS_NODEV);
    move_mount(mfd, "", sfd, AT_FDCWD, "/mnt", MOVE_MOUNT_F_EMPTY_PATH);

    If an error is reported at any step, an error message may be available to be
    read() back (ENODATA will be reported if there isn't an error available) in
    the form:

    "e :"
    "e SELinux:Mount on mountpoint not permitted"

    Once fsmount() has been called, further fsconfig() calls will incur EBUSY,
    even if the fsmount() fails. read() is still possible to retrieve error
    information.

    The fsopen() syscall creates a mount context and hangs it of the fd that it
    returns.

    Netlink is not used because it is optional and would make the core VFS
    dependent on the networking layer and also potentially add network
    namespace issues.

    Note that, for the moment, the caller must have SYS_CAP_ADMIN to use
    fsopen().

    Signed-off-by: David Howells
    cc: linux-api@vger.kernel.org
    Signed-off-by: Al Viro

    David Howells
     
  • dadd2299a   Make anon_inodes unconditional ... Browse Code »

    Make the anon_inodes facility unconditional so that it can be used by core
    VFS code.

    Signed-off-by: David Howells
    Signed-off-by: Al Viro

    David Howells
     

13 Mar, 2019

1 commit

  • 7b47a9e7c   Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs ... Browse Code »

    Pull vfs mount infrastructure updates from Al Viro:
    "The rest of core infrastructure; no new syscalls in that pile, but the
    old parts are switched to new infrastructure. At that point
    conversions of individual filesystems can happen independently; some
    are done here (afs, cgroup, procfs, etc.), there's also a large series
    outside of that pile dealing with NFS (quite a bit of option-parsing
    stuff is getting used there - it's one of the most convoluted
    filesystems in terms of mount-related logics), but NFS bits are the
    next cycle fodder.

    It got seriously simplified since the last cycle; documentation is
    probably the weakest bit at the moment - I considered dropping the
    commit introducing Documentation/filesystems/mount_api.txt (cutting
    the size increase by quarter ;-), but decided that it would be better
    to fix it up after -rc1 instead.

    That pile allows to do followup work in independent branches, which
    should make life much easier for the next cycle. fs/super.c size
    increase is unpleasant; there's a followup series that allows to
    shrink it considerably, but I decided to leave that until the next
    cycle"

    * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
    afs: Use fs_context to pass parameters over automount
    afs: Add fs_context support
    vfs: Add some logging to the core users of the fs_context log
    vfs: Implement logging through fs_context
    vfs: Provide documentation for new mount API
    vfs: Remove kern_mount_data()
    hugetlbfs: Convert to fs_context
    cpuset: Use fs_context
    kernfs, sysfs, cgroup, intel_rdt: Support fs_context
    cgroup: store a reference to cgroup_ns into cgroup_fs_context
    cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper
    cgroup_do_mount(): massage calling conventions
    cgroup: stash cgroup_root reference into cgroup_fs_context
    cgroup2: switch to option-by-option parsing
    cgroup1: switch to option-by-option parsing
    cgroup: take options parsing into ->parse_monolithic()
    cgroup: fold cgroup1_mount() into cgroup1_get_tree()
    cgroup: start switching to fs_context
    ipc: Convert mqueue fs to fs_context
    proc: Add fs_context support to procfs
    ...

    Linus Torvalds
     

10 Mar, 2019

1 commit

  • 92fff53b7   Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi ... Browse Code »

    Pull SCSI updates from James Bottomley:
    "This is mostly update of the usual drivers: arcmsr, qla2xxx, lpfc,
    hisi_sas, target/iscsi and target/core.

    Additionally Christoph refactored gdth as part of the dma changes. The
    major mid-layer change this time is the removal of bidi commands and
    with them the whole of the osd/exofs driver and filesystem. This is a
    major simplification for block and mq in particular"

    * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (240 commits)
    scsi: cxgb4i: validate tcp sequence number only if chip version pf
    scsi: core: replace GFP_ATOMIC with GFP_KERNEL in scsi_scan.c
    scsi: mpt3sas: Add missing breaks in switch statements
    scsi: aacraid: Fix missing break in switch statement
    scsi: kill command serial number
    scsi: csiostor: drop serial_number usage
    scsi: mvumi: use request tag instead of serial_number
    scsi: dpt_i2o: remove serial number usage
    scsi: st: osst: Remove negative constant left-shifts
    scsi: ufs-bsg: Allow reading descriptors
    scsi: ufs: Allow reading descriptor via raw upiu
    scsi: ufs-bsg: Change the calling convention for write descriptor
    scsi: ufs: Remove unused device quirks
    Revert "scsi: ufs: disable vccq if it's not needed by UFS device"
    scsi: megaraid_sas: Remove a bunch of set but not used variables
    scsi: clean obsolete return values of eh_timed_out
    scsi: sd: Optimal I/O size should be a multiple of physical block size
    scsi: MAINTAINERS: SCSI initiator and target tweaks
    scsi: fcoe: make use of fip_mode enum complete
    ...

    Linus Torvalds
     

09 Mar, 2019

1 commit

  • 38e7571c0   Merge tag 'io_uring-2019-03-06' of git://git.kernel.dk/linux-block ... Browse Code »

    Pull io_uring IO interface from Jens Axboe:
    "Second attempt at adding the io_uring interface.

    Since the first one, we've added basic unit testing of the three
    system calls, that resides in liburing like the other unit tests that
    we have so far. It'll take a while to get full coverage of it, but
    we're working towards it. I've also added two basic test programs to
    tools/io_uring. One uses the raw interface and has support for all the
    various features that io_uring supports outside of standard IO, like
    fixed files, fixed IO buffers, and polled IO. The other uses the
    liburing API, and is a simplified version of cp(1).

    This adds support for a new IO interface, io_uring.

    io_uring allows an application to communicate with the kernel through
    two rings, the submission queue (SQ) and completion queue (CQ) ring.
    This allows for very efficient handling of IOs, see the v5 posting for
    some basic numbers:

    https://lore.kernel.org/linux-block/20190116175003.17880-1-axboe@kernel.dk/

    Outside of just efficiency, the interface is also flexible and
    extendable, and allows for future use cases like the upcoming NVMe
    key-value store API, networked IO, and so on. It also supports async
    buffered IO, something that we've always failed to support in the
    kernel.

    Outside of basic IO features, it supports async polled IO as well.
    This particular feature has already been tested at Facebook months ago
    for flash storage boxes, with 25-33% improvements. It makes polled IO
    actually useful for real world use cases, where even basic flash sees
    a nice win in terms of efficiency, latency, and performance. These
    boxes were IOPS bound before, now they are not.

    This series adds three new system calls. One for setting up an
    io_uring instance (io_uring_setup(2)), one for submitting/completing
    IO (io_uring_enter(2)), and one for aux functions like registrating
    file sets, buffers, etc (io_uring_register(2)). Through the help of
    Arnd, I've coordinated the syscall numbers so merge on that front
    should be painless.

    Jon did a writeup of the interface a while back, which (except for
    minor details that have been tweaked) is still accurate. Find that
    here:

    https://lwn.net/Articles/776703/

    Huge thanks to Al Viro for helping getting the reference cycle code
    correct, and to Jann Horn for his extensive reviews focused on both
    security and bugs in general.

    There's a userspace library that provides basic functionality for
    applications that don't need or want to care about how to fiddle with
    the rings directly. It has helpers to allow applications to easily set
    up an io_uring instance, and submit/complete IO through it without
    knowing about the intricacies of the rings. It also includes man pages
    (thanks to Jeff Moyer), and will continue to grow support helper
    functions and features as time progresses. Find it here:

    git://git.kernel.dk/liburing

    Fio has full support for the raw interface, both in the form of an IO
    engine (io_uring), but also with a small test application (t/io_uring)
    that can exercise and benchmark the interface"

    * tag 'io_uring-2019-03-06' of git://git.kernel.dk/linux-block:
    io_uring: add a few test tools
    io_uring: allow workqueue item to handle multiple buffered requests
    io_uring: add support for IORING_OP_POLL
    io_uring: add io_kiocb ref count
    io_uring: add submission polling
    io_uring: add file set registration
    net: split out functions related to registering inflight socket files
    io_uring: add support for pre-mapped user IO buffers
    block: implement bio helper to add iter bvec pages to bio
    io_uring: batch io_kiocb allocation
    io_uring: use fget/fput_many() for file references
    fs: add fget_many() and fput_many()
    io_uring: support for IO polling
    io_uring: add fsync support
    Add io_uring IO interface

    Linus Torvalds
     

28 Feb, 2019

2 commits

  • 2b188cc1b   Add io_uring IO interface ... Browse Code »

    The submission queue (SQ) and completion queue (CQ) rings are shared
    between the application and the kernel. This eliminates the need to
    copy data back and forth to submit and complete IO.

    IO submissions use the io_uring_sqe data structure, and completions
    are generated in the form of io_uring_cqe data structures. The SQ
    ring is an index into the io_uring_sqe array, which makes it possible
    to submit a batch of IOs without them being contiguous in the ring.
    The CQ ring is always contiguous, as completion events are inherently
    unordered, and hence any io_uring_cqe entry can point back to an
    arbitrary submission.

    Two new system calls are added for this:

    io_uring_setup(entries, params)
    Sets up an io_uring instance for doing async IO. On success,
    returns a file descriptor that the application can mmap to
    gain access to the SQ ring, CQ ring, and io_uring_sqes.

    io_uring_enter(fd, to_submit, min_complete, flags, sigset, sigsetsize)
    Initiates IO against the rings mapped to this fd, or waits for
    them to complete, or both. The behavior is controlled by the
    parameters passed in. If 'to_submit' is non-zero, then we'll
    try and submit new IO. If IORING_ENTER_GETEVENTS is set, the
    kernel will wait for 'min_complete' events, if they aren't
    already available. It's valid to set IORING_ENTER_GETEVENTS
    and 'min_complete' == 0 at the same time, this allows the
    kernel to return already completed events without waiting
    for them. This is useful only for polling, as for IRQ
    driven IO, the application can just check the CQ ring
    without entering the kernel.

    With this setup, it's possible to do async IO with a single system
    call. Future developments will enable polled IO with this interface,
    and polled submission as well. The latter will enable an application
    to do IO without doing ANY system calls at all.

    For IRQ driven IO, an application only needs to enter the kernel for
    completions if it wants to wait for them to occur.

    Each io_uring is backed by a workqueue, to support buffered async IO
    as well. We will only punt to an async context if the command would
    need to wait for IO on the device side. Any data that can be accessed
    directly in the page cache is done inline. This avoids the slowness
    issue of usual threadpools, since cached data is accessed as quickly
    as a sync interface.

    Sample application: http://git.kernel.dk/cgit/fio/plain/t/io_uring.c

    Reviewed-by: Hannes Reinecke
    Signed-off-by: Jens Axboe

    Jens Axboe
     
  • 31d921c7f   vfs: Add configuration parser helpers ... Browse Code »

    Because the new API passes in key,value parameters, match_token() cannot be
    used with it. Instead, provide three new helpers to aid with parsing:

    (1) fs_parse(). This takes a parameter and a simple static description of
    all the parameters and maps the key name to an ID. It returns 1 on a
    match, 0 on no match if unknowns should be ignored and some other
    negative error code on a parse error.

    The parameter description includes a list of key names to IDs, desired
    parameter types and a list of enumeration name -> ID mappings.

    [!] Note that for the moment I've required that the key->ID mapping
    array is expected to be sorted and unterminated. The size of the
    array is noted in the fsconfig_parser struct. This allows me to use
    bsearch(), but I'm not sure any performance gain is worth the hassle
    of requiring people to keep the array sorted.

    The parameter type array is sized according to the number of parameter
    IDs and is indexed directly. The optional enum mapping array is an
    unterminated, unsorted list and the size goes into the fsconfig_parser
    struct.

    The function can do some additional things:

    (a) If it's not ambiguous and no value is given, the prefix "no" on
    a key name is permitted to indicate that the parameter should
    be considered negatory.

    (b) If the desired type is a single simple integer, it will perform
    an appropriate conversion and store the result in a union in
    the parse result.

    (c) If the desired type is an enumeration, {key ID, name} will be
    looked up in the enumeration list and the matching value will
    be stored in the parse result union.

    (d) Optionally generate an error if the key is unrecognised.

    This is called something like:

    enum rdt_param {
    Opt_cdp,
    Opt_cdpl2,
    Opt_mba_mpbs,
    nr__rdt_params
    };

    const struct fs_parameter_spec rdt_param_specs[nr__rdt_params] = {
    [Opt_cdp] = { fs_param_is_bool },
    [Opt_cdpl2] = { fs_param_is_bool },
    [Opt_mba_mpbs] = { fs_param_is_bool },
    };

    const const char *const rdt_param_keys[nr__rdt_params] = {
    [Opt_cdp] = "cdp",
    [Opt_cdpl2] = "cdpl2",
    [Opt_mba_mpbs] = "mba_mbps",
    };

    const struct fs_parameter_description rdt_parser = {
    .name = "rdt",
    .nr_params = nr__rdt_params,
    .keys = rdt_param_keys,
    .specs = rdt_param_specs,
    .no_source = true,
    };

    int rdt_parse_param(struct fs_context *fc,
    struct fs_parameter *param)
    {
    struct fs_parse_result parse;
    struct rdt_fs_context *ctx = rdt_fc2context(fc);
    int ret;

    ret = fs_parse(fc, &rdt_parser, param, &parse);
    if (ret < 0)
    return ret;

    switch (parse.key) {
    case Opt_cdp:
    ctx->enable_cdpl3 = true;
    return 0;
    case Opt_cdpl2:
    ctx->enable_cdpl2 = true;
    return 0;
    case Opt_mba_mpbs:
    ctx->enable_mba_mbps = true;
    return 0;
    }

    return -EINVAL;
    }

    (2) fs_lookup_param(). This takes a { dirfd, path, LOOKUP_EMPTY? } or
    string value and performs an appropriate path lookup to convert it
    into a path object, which it will then return.

    If the desired type was a blockdev, the type of the looked up inode
    will be checked to make sure it is one.

    This can be used like:

    enum foo_param {
    Opt_source,
    nr__foo_params
    };

    const struct fs_parameter_spec foo_param_specs[nr__foo_params] = {
    [Opt_source] = { fs_param_is_blockdev },
    };

    const char *char foo_param_keys[nr__foo_params] = {
    [Opt_source] = "source",
    };

    const struct constant_table foo_param_alt_keys[] = {
    { "device", Opt_source },
    };

    const struct fs_parameter_description foo_parser = {
    .name = "foo",
    .nr_params = nr__foo_params,
    .nr_alt_keys = ARRAY_SIZE(foo_param_alt_keys),
    .keys = foo_param_keys,
    .alt_keys = foo_param_alt_keys,
    .specs = foo_param_specs,
    };

    int foo_parse_param(struct fs_context *fc,
    struct fs_parameter *param)
    {
    struct fs_parse_result parse;
    struct foo_fs_context *ctx = foo_fc2context(fc);
    int ret;

    ret = fs_parse(fc, &foo_parser, param, &parse);
    if (ret < 0)
    return ret;

    switch (parse.key) {
    case Opt_source:
    return fs_lookup_param(fc, &foo_parser, param,
    &parse, &ctx->source);
    default:
    return -EINVAL;
    }
    }

    (3) lookup_constant(). This takes a table of named constants and looks up
    the given name within it. The table is expected to be sorted such
    that bsearch() be used upon it.

    Possibly I should require the table be terminated and just use a
    for-loop to scan it instead of using bsearch() to reduce hassle.

    Tables look something like:

    static const struct constant_table bool_names[] = {
    { "0", false },
    { "1", true },
    { "false", false },
    { "no", false },
    { "true", true },
    { "yes", true },
    };

    and a lookup is done with something like:

    b = lookup_constant(bool_names, param->string, -1);

    Additionally, optional validation routines for the parameter description
    are provided that can be enabled at compile time. A later patch will
    invoke these when a filesystem is registered.

    Signed-off-by: David Howells
    Signed-off-by: Al Viro

    David Howells