20 Jun, 2017

2 commits

  • So I've noticed a number of instances where it was not obvious from the
    code whether ->task_list was for a wait-queue head or a wait-queue entry.

    Furthermore, there's a number of wait-queue users where the lists are
    not for 'tasks' but other entities (poll tables, etc.), in which case
    the 'task_list' name is actively confusing.

    To clear this all up, name the wait-queue head and entry list structure
    fields unambiguously:

    struct wait_queue_head::task_list => ::head
    struct wait_queue_entry::task_list => ::entry

    For example, this code:

    rqw->wait.task_list.next != &wait->task_list

    ... is was pretty unclear (to me) what it's doing, while now it's written this way:

    rqw->wait.head.next != &wait->entry

    ... which makes it pretty clear that we are iterating a list until we see the head.

    Other examples are:

    list_for_each_entry_safe(pos, next, &x->task_list, task_list) {
    list_for_each_entry(wq, &fence->wait.task_list, task_list) {

    ... where it's unclear (to me) what we are iterating, and during review it's
    hard to tell whether it's trying to walk a wait-queue entry (which would be
    a bug), while now it's written as:

    list_for_each_entry_safe(pos, next, &x->head, entry) {
    list_for_each_entry(wq, &fence->wait.head, entry) {

    Cc: Linus Torvalds
    Cc: Peter Zijlstra
    Cc: Thomas Gleixner
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: Ingo Molnar

    Ingo Molnar
     
  • Rename:

    wait_queue_t => wait_queue_entry_t

    'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue",
    but in reality it's a queue *entry*. The 'real' queue is the wait queue head,
    which had to carry the name.

    Start sorting this out by renaming it to 'wait_queue_entry_t'.

    This also allows the real structure name 'struct __wait_queue' to
    lose its double underscore and become 'struct wait_queue_entry',
    which is the more canonical nomenclature for such data types.

    Cc: Linus Torvalds
    Cc: Peter Zijlstra
    Cc: Thomas Gleixner
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: Ingo Molnar

    Ingo Molnar
     

06 May, 2017

1 commit

  • Pull orangefs updates from Mike Marshall:
    "Orangefs cleanups, fixes and statx support.

    Some cleanups:

    - remove unused get_fsid_from_ino
    - fix bounds check for listxattr
    - clean up oversize xattr validation
    - do not set getattr_time on orangefs_lookup
    - return from orangefs_devreq_read quickly if possible
    - do not wait for timeout if umounting
    - handle zero size write in debugfs

    Bug fixes:

    - do not check possibly stale size on truncate
    - ensure the userspace component is unmounted if mount fails
    - total reimplementation of dir.c

    New feature:

    - implement statx

    The new implementation of dir.c is kind of a big deal, all new code.
    It has been posted to fs-devel during the previous rc period, we
    didn't get much review or feedback from there, but it has been
    reviewed very heavily here, so much so that we have two entire
    versions of the reimplementation.

    Not only does the new implementation fix some xfstests, but it passes
    all the new tests we made here that involve seeking and rewinding and
    giant directories and long file names. The new dir code has three
    patches itself:

    - skip forward to the next directory entry if seek is short
    - invalidate stored directory on seek
    - count directory pieces correctly"

    * tag 'for-linus-4.12-ofs-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
    orangefs: count directory pieces correctly
    orangefs: invalidate stored directory on seek
    orangefs: skip forward to the next directory entry if seek is short
    orangefs: handle zero size write in debugfs
    orangefs: do not wait for timeout if umounting
    orangefs: return from orangefs_devreq_read quickly if possible
    orangefs: ensure the userspace component is unmounted if mount fails
    orangefs: do not check possibly stale size on truncate
    orangefs: implement statx
    orangefs: remove ORANGEFS_READDIR macros
    orangefs: support very large directories
    orangefs: support llseek on directories
    orangefs: rewrite readdir to fix several bugs
    orangefs: do not set getattr_time on orangefs_lookup
    orangefs: clean up oversize xattr validation
    orangefs: fix bounds check for listxattr
    orangefs: remove unused get_fsid_from_ino

    Linus Torvalds
     

05 May, 2017

3 commits

  • A large directory full of differently sized file names triggered this.
    Most directories, even very large directories with shorter names, would
    be lucky enough to fit in one server response.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • If an application seeks to a position before the point which has been
    read, it must want updates which have been made to the directory. So
    delete the copy stored in the kernel so it will be fetched again.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • If userspace seeks to a position in the stream which is not correct, it
    would have returned EIO because the data in the buffer at that offset
    would be incorrect. This and the userspace daemon returning a corrupt
    directory are indistinguishable.

    Now if the data does not look right, skip forward to the next chunk and
    try again. The motivation is that if the directory changes, an
    application may seek to a position that was valid and no longer is valid.

    It is not yet possible for a directory to change.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     

27 Apr, 2017

14 commits

  • If we write zero bytes to this debugfs file, then it will cause an
    underflow when we do copy_from_user(buf, ubuf, count - 1). Debugfs can
    normally only be written to by root so the impact of this is low.

    Signed-off-by: Dan Carpenter
    Signed-off-by: Mike Marshall

    Dan Carpenter
     
  • When the computer is turned off, all the processes are killed and then
    all the filesystems are umounted. OrangeFS should not wait for the
    userspace daemon to come back in that case.

    This only works for plain umount(2). To actually take advantage of this
    interactively, `umount -f' is needed; otherwise umount will issue a
    statfs first, which will wait for the userspace daemon to come back.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • It is not necessary to take the lock and search through the request list
    if the list is empty.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • If the mount is aborted after userspace has been asked to mount,
    userspace must be told to unmount.

    Ordinarily orangefs_kill_sb does the unmount. However it cannot be
    called if the superblock has not been set up. This is a very narrow
    window.

    The NULL fs_id is not unmounted.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • Let the server figure this out because our size might be out of date or
    not present.

    The bug was that

    xfs_io -f -t -c "pread -v 0 100" /mnt/foo
    echo "Test" > /mnt/foo
    xfs_io -f -t -c "pread -v 0 100" /mnt/foo

    fails because the second truncate did not happen if nothing had
    requested the size after the write in echo. Thus i_size was zero (not
    present) and the orangefs_setattr though i_size was zero and there was
    nothing to do.

    Signed-off-by: Martin Brandenburg
    Cc: stable@vger.kernel.org
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • Fortunately OrangeFS has had a getattr request mask for a long time.

    The server basically has two difficulty levels for attributes. Fetching
    any attribute except size requires communicating with the metadata
    server for that handle. Since all the attributes are right there, it
    makes sense to return them all. Fetching the size requires
    communicating with every I/O server (that the file is distributed
    across). Therefore if asked for anything except size, get everything
    except size, and if asked for size, get everything.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • They are clones of the ORANGEFS_ITERATE macros in use elsewhere. Delete
    ORANGEFS_ITERATE_NEXT which is a hack previously used by readdir.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • This works by maintaining a linked list of pages which the directory
    has been read into rather than one giant fixed-size buffer.

    This replaces code which limits the total directory size to the total
    amount that could be returned in one server request. Since filenames
    are usually considerably shorter than the maximum, the old code could
    usually handle several server requests before running out of space.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • This and the previous commit fix xfstests generic/257.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • In the past, readdir assumed that the user buffer will be large enough
    that all entries from the server will fit. If this was not true,
    entries would be skipped.

    Since it works now, request 512 entries rather than 96 per server
    operation.

    Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • Since orangefs_lookup calls orangefs_iget which calls
    orangefs_inode_getattr, getattr_time will get set.

    Signed-off-by: Martin Brandenburg
    Cc: stable@vger.kernel.org
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • Also don't check flags as this has been validated by the VFS already.

    Fix an off-by-one error in the max size checking.

    Stop logging just because userspace wants to write attributes which do
    not fit.

    This and the previous commit fix xfstests generic/020.

    Signed-off-by: Martin Brandenburg
    Cc: stable@vger.kernel.org
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • Signed-off-by: Martin Brandenburg
    Cc: stable@vger.kernel.org
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     

22 Apr, 2017

1 commit


18 Apr, 2017

1 commit


16 Apr, 2017

1 commit

  • Otherwise lockdep says:

    [ 1337.483798] ================================================
    [ 1337.483999] [ BUG: lock held when returning to user space! ]
    [ 1337.484252] 4.11.0-rc6 #19 Not tainted
    [ 1337.484423] ------------------------------------------------
    [ 1337.484626] mount/14766 is leaving the kernel with locks still held!
    [ 1337.484841] 1 lock held by mount/14766:
    [ 1337.485017] #0: (&type->s_umount_key#33/1){+.+.+.}, at: [] sget_userns+0x2af/0x520

    Caught by xfstests generic/413 which tried to mount with the unsupported
    mount option dax. Then xfstests generic/422 ran sync which deadlocks.

    Signed-off-by: Martin Brandenburg
    Acked-by: Mike Marshall
    Cc: stable@vger.kernel.org
    Signed-off-by: Linus Torvalds

    Martin Brandenburg
     

08 Apr, 2017

1 commit

  • Without this fix (and another to the userspace component itself
    described later), the kernel will be unable to process any OrangeFS
    requests after the userspace component is restarted (due to a crash or
    at the administrator's behest).

    The bug here is that inside orangefs_remount, the orangefs_request_mutex
    is locked. When the userspace component restarts while the filesystem
    is mounted, it sends a ORANGEFS_DEV_REMOUNT_ALL ioctl to the device,
    which causes the kernel to send it a few requests aimed at synchronizing
    the state between the two. While this is happening the
    orangefs_request_mutex is locked to prevent any other requests going
    through.

    This is only half of the bugfix. The other half is in the userspace
    component which outright ignores(!) requests made before it considers
    the filesystem remounted, which is after the ioctl returns. Of course
    the ioctl doesn't return until after the userspace component responds to
    the request it ignores. The userspace component has been changed to
    allow ORANGEFS_VFS_OP_FEATURES regardless of the mount status.

    Mike Marshall says:
    "I've tested this patch against the fixed userspace part. This patch is
    real important, I hope it can make it into 4.11...

    Here's what happens when the userspace daemon is restarted, without
    the patch:

    =============================================
    [ INFO: possible recursive locking detected ]
    [ 4.10.0-00007-ge98bdb3 #1 Not tainted ]
    ---------------------------------------------
    pvfs2-client-co/29032 is trying to acquire lock:
    (orangefs_request_mutex){+.+.+.}, at: service_operation+0x3c7/0x7b0 [orangefs]
    but task is already holding lock:
    (orangefs_request_mutex){+.+.+.}, at: dispatch_ioctl_command+0x1bf/0x330 [orangefs]

    CPU: 0 PID: 29032 Comm: pvfs2-client-co Not tainted 4.10.0-00007-ge98bdb3 #1
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014
    Call Trace:
    __lock_acquire+0x7eb/0x1290
    lock_acquire+0xe8/0x1d0
    mutex_lock_killable_nested+0x6f/0x6e0
    service_operation+0x3c7/0x7b0 [orangefs]
    orangefs_remount+0xea/0x150 [orangefs]
    dispatch_ioctl_command+0x227/0x330 [orangefs]
    orangefs_devreq_ioctl+0x29/0x70 [orangefs]
    do_vfs_ioctl+0xa3/0x6e0
    SyS_ioctl+0x79/0x90"

    Signed-off-by: Martin Brandenburg
    Acked-by: Mike Marshall
    Cc: stable@vger.kernel.org
    Signed-off-by: Linus Torvalds

    Martin Brandenburg
     

04 Mar, 2017

2 commits

  • Pull vfs 'statx()' update from Al Viro.

    This adds the new extended stat() interface that internally subsumes our
    previous stat interfaces, and allows user mode to specify in more detail
    what kind of information it wants.

    It also allows for some explicit synchronization information to be
    passed to the filesystem, which can be relevant for network filesystems:
    is the cached value ok, or do you need open/close consistency, or what?

    From David Howells.

    Andreas Dilger points out that the first version of the extended statx
    interface was posted June 29, 2010:

    https://www.spinics.net/lists/linux-fsdevel/msg33831.html

    * 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
    statx: Add a system call to make enhanced file info available

    Linus Torvalds
     
  • Pull sched.h split-up from Ingo Molnar:
    "The point of these changes is to significantly reduce the
    header footprint, to speed up the kernel build and to
    have a cleaner header structure.

    After these changes the new 's typical preprocessed
    size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
    lines), which is around 40% faster to build on typical configs.

    Not much changed from the last version (-v2) posted three weeks ago: I
    eliminated quirks, backmerged fixes plus I rebased it to an upstream
    SHA1 from yesterday that includes most changes queued up in -next plus
    all sched.h changes that were pending from Andrew.

    I've re-tested the series both on x86 and on cross-arch defconfigs,
    and did a bisectability test at a number of random points.

    I tried to test as many build configurations as possible, but some
    build breakage is probably still left - but it should be mostly
    limited to architectures that have no cross-compiler binaries
    available on kernel.org, and non-default configurations"

    * 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
    sched/headers: Clean up
    sched/headers: Remove #ifdefs from
    sched/headers: Remove the include from
    sched/headers, hrtimer: Remove the include from
    sched/headers, x86/apic: Remove the header inclusion from
    sched/headers, timers: Remove the include from
    sched/headers: Remove from
    sched/headers: Remove from
    sched/core: Remove unused prefetch_stack()
    sched/headers: Remove from
    sched/headers: Remove the 'init_pid_ns' prototype from
    sched/headers: Remove from
    sched/headers: Remove from
    sched/headers: Remove the runqueue_is_locked() prototype
    sched/headers: Remove from
    sched/headers: Remove from
    sched/headers: Remove from
    sched/headers: Remove from
    sched/headers: Remove the include from
    sched/headers: Remove from
    ...

    Linus Torvalds
     

03 Mar, 2017

2 commits

  • Add a system call to make extended file information available, including
    file creation and some attribute flags where available through the
    underlying filesystem.

    The getattr inode operation is altered to take two additional arguments: a
    u32 request_mask and an unsigned int flags that indicate the
    synchronisation mode. This change is propagated to the vfs_getattr*()
    function.

    Functions like vfs_stat() are now inline wrappers around new functions
    vfs_statx() and vfs_statx_fd() to reduce stack usage.

    ========
    OVERVIEW
    ========

    The idea was initially proposed as a set of xattrs that could be retrieved
    with getxattr(), but the general preference proved to be for a new syscall
    with an extended stat structure.

    A number of requests were gathered for features to be included. The
    following have been included:

    (1) Make the fields a consistent size on all arches and make them large.

    (2) Spare space, request flags and information flags are provided for
    future expansion.

    (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
    __s64).

    (4) Creation time: The SMB protocol carries the creation time, which could
    be exported by Samba, which will in turn help CIFS make use of
    FS-Cache as that can be used for coherency data (stx_btime).

    This is also specified in NFSv4 as a recommended attribute and could
    be exported by NFSD [Steve French].

    (5) Lightweight stat: Ask for just those details of interest, and allow a
    netfs (such as NFS) to approximate anything not of interest, possibly
    without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
    Dilger] (AT_STATX_DONT_SYNC).

    (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
    its cached attributes are up to date [Trond Myklebust]
    (AT_STATX_FORCE_SYNC).

    And the following have been left out for future extension:

    (7) Data version number: Could be used by userspace NFS servers [Aneesh
    Kumar].

    Can also be used to modify fill_post_wcc() in NFSD which retrieves
    i_version directly, but has just called vfs_getattr(). It could get
    it from the kstat struct if it used vfs_xgetattr() instead.

    (There's disagreement on the exact semantics of a single field, since
    not all filesystems do this the same way).

    (8) BSD stat compatibility: Including more fields from the BSD stat such
    as creation time (st_btime) and inode generation number (st_gen)
    [Jeremy Allison, Bernd Schubert].

    (9) Inode generation number: Useful for FUSE and userspace NFS servers
    [Bernd Schubert].

    (This was asked for but later deemed unnecessary with the
    open-by-handle capability available and caused disagreement as to
    whether it's a security hole or not).

    (10) Extra coherency data may be useful in making backups [Andreas Dilger].

    (No particular data were offered, but things like last backup
    timestamp, the data version number and the DOS archive bit would come
    into this category).

    (11) Allow the filesystem to indicate what it can/cannot provide: A
    filesystem can now say it doesn't support a standard stat feature if
    that isn't available, so if, for instance, inode numbers or UIDs don't
    exist or are fabricated locally...

    (This requires a separate system call - I have an fsinfo() call idea
    for this).

    (12) Store a 16-byte volume ID in the superblock that can be returned in
    struct xstat [Steve French].

    (Deferred to fsinfo).

    (13) Include granularity fields in the time data to indicate the
    granularity of each of the times (NFSv4 time_delta) [Steve French].

    (Deferred to fsinfo).

    (14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
    Note that the Linux IOC flags are a mess and filesystems such as Ext4
    define flags that aren't in linux/fs.h, so translation in the kernel
    may be a necessity (or, possibly, we provide the filesystem type too).

    (Some attributes are made available in stx_attributes, but the general
    feeling was that the IOC flags were to ext[234]-specific and shouldn't
    be exposed through statx this way).

    (15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
    Michael Kerrisk].

    (Deferred, probably to fsinfo. Finding out if there's an ACL or
    seclabal might require extra filesystem operations).

    (16) Femtosecond-resolution timestamps [Dave Chinner].

    (A __reserved field has been left in the statx_timestamp struct for
    this - if there proves to be a need).

    (17) A set multiple attributes syscall to go with this.

    ===============
    NEW SYSTEM CALL
    ===============

    The new system call is:

    int ret = statx(int dfd,
    const char *filename,
    unsigned int flags,
    unsigned int mask,
    struct statx *buffer);

    The dfd, filename and flags parameters indicate the file to query, in a
    similar way to fstatat(). There is no equivalent of lstat() as that can be
    emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
    also no equivalent of fstat() as that can be emulated by passing a NULL
    filename to statx() with the fd of interest in dfd.

    Whether or not statx() synchronises the attributes with the backing store
    can be controlled by OR'ing a value into the flags argument (this typically
    only affects network filesystems):

    (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
    respect.

    (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
    its attributes with the server - which might require data writeback to
    occur to get the timestamps correct.

    (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
    network filesystem. The resulting values should be considered
    approximate.

    mask is a bitmask indicating the fields in struct statx that are of
    interest to the caller. The user should set this to STATX_BASIC_STATS to
    get the basic set returned by stat(). It should be noted that asking for
    more information may entail extra I/O operations.

    buffer points to the destination for the data. This must be 256 bytes in
    size.

    ======================
    MAIN ATTRIBUTES RECORD
    ======================

    The following structures are defined in which to return the main attribute
    set:

    struct statx_timestamp {
    __s64 tv_sec;
    __s32 tv_nsec;
    __s32 __reserved;
    };

    struct statx {
    __u32 stx_mask;
    __u32 stx_blksize;
    __u64 stx_attributes;
    __u32 stx_nlink;
    __u32 stx_uid;
    __u32 stx_gid;
    __u16 stx_mode;
    __u16 __spare0[1];
    __u64 stx_ino;
    __u64 stx_size;
    __u64 stx_blocks;
    __u64 __spare1[1];
    struct statx_timestamp stx_atime;
    struct statx_timestamp stx_btime;
    struct statx_timestamp stx_ctime;
    struct statx_timestamp stx_mtime;
    __u32 stx_rdev_major;
    __u32 stx_rdev_minor;
    __u32 stx_dev_major;
    __u32 stx_dev_minor;
    __u64 __spare2[14];
    };

    The defined bits in request_mask and stx_mask are:

    STATX_TYPE Want/got stx_mode & S_IFMT
    STATX_MODE Want/got stx_mode & ~S_IFMT
    STATX_NLINK Want/got stx_nlink
    STATX_UID Want/got stx_uid
    STATX_GID Want/got stx_gid
    STATX_ATIME Want/got stx_atime{,_ns}
    STATX_MTIME Want/got stx_mtime{,_ns}
    STATX_CTIME Want/got stx_ctime{,_ns}
    STATX_INO Want/got stx_ino
    STATX_SIZE Want/got stx_size
    STATX_BLOCKS Want/got stx_blocks
    STATX_BASIC_STATS [The stuff in the normal stat struct]
    STATX_BTIME Want/got stx_btime{,_ns}
    STATX_ALL [All currently available stuff]

    stx_btime is the file creation time, stx_mask is a bitmask indicating the
    data provided and __spares*[] are where as-yet undefined fields can be
    placed.

    Time fields are structures with separate seconds and nanoseconds fields
    plus a reserved field in case we want to add even finer resolution. Note
    that times will be negative if before 1970; in such a case, the nanosecond
    fields will also be negative if not zero.

    The bits defined in the stx_attributes field convey information about a
    file, how it is accessed, where it is and what it does. The following
    attributes map to FS_*_FL flags and are the same numerical value:

    STATX_ATTR_COMPRESSED File is compressed by the fs
    STATX_ATTR_IMMUTABLE File is marked immutable
    STATX_ATTR_APPEND File is append-only
    STATX_ATTR_NODUMP File is not to be dumped
    STATX_ATTR_ENCRYPTED File requires key to decrypt in fs

    Within the kernel, the supported flags are listed by:

    KSTAT_ATTR_FS_IOC_FLAGS

    [Are any other IOC flags of sufficient general interest to be exposed
    through this interface?]

    New flags include:

    STATX_ATTR_AUTOMOUNT Object is an automount trigger

    These are for the use of GUI tools that might want to mark files specially,
    depending on what they are.

    Fields in struct statx come in a number of classes:

    (0) stx_dev_*, stx_blksize.

    These are local system information and are always available.

    (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
    stx_size, stx_blocks.

    These will be returned whether the caller asks for them or not. The
    corresponding bits in stx_mask will be set to indicate whether they
    actually have valid values.

    If the caller didn't ask for them, then they may be approximated. For
    example, NFS won't waste any time updating them from the server,
    unless as a byproduct of updating something requested.

    If the values don't actually exist for the underlying object (such as
    UID or GID on a DOS file), then the bit won't be set in the stx_mask,
    even if the caller asked for the value. In such a case, the returned
    value will be a fabrication.

    Note that there are instances where the type might not be valid, for
    instance Windows reparse points.

    (2) stx_rdev_*.

    This will be set only if stx_mode indicates we're looking at a
    blockdev or a chardev, otherwise will be 0.

    (3) stx_btime.

    Similar to (1), except this will be set to 0 if it doesn't exist.

    =======
    TESTING
    =======

    The following test program can be used to test the statx system call:

    samples/statx/test-statx.c

    Just compile and run, passing it paths to the files you want to examine.
    The file is built automatically if CONFIG_SAMPLES is enabled.

    Here's some example output. Firstly, an NFS directory that crosses to
    another FSID. Note that the AUTOMOUNT attribute is set because transiting
    this directory will cause d_automount to be invoked by the VFS.

    [root@andromeda ~]# /tmp/test-statx -A /warthog/data
    statx(/warthog/data) = 0
    results=7ff
    Size: 4096 Blocks: 8 IO Block: 1048576 directory
    Device: 00:26 Inode: 1703937 Links: 125
    Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
    Access: 2016-11-24 09:02:12.219699527+0000
    Modify: 2016-11-17 10:44:36.225653653+0000
    Change: 2016-11-17 10:44:36.225653653+0000
    Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)

    Secondly, the result of automounting on that directory.

    [root@andromeda ~]# /tmp/test-statx /warthog/data
    statx(/warthog/data) = 0
    results=7ff
    Size: 4096 Blocks: 8 IO Block: 1048576 directory
    Device: 00:27 Inode: 2 Links: 125
    Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
    Access: 2016-11-24 09:02:12.219699527+0000
    Modify: 2016-11-17 10:44:36.225653653+0000
    Change: 2016-11-17 10:44:36.225653653+0000

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

    David Howells
     
  • Pull vfs pile two from Al Viro:

    - orangefs fix

    - series of fs/namei.c cleanups from me

    - VFS stuff coming from overlayfs tree

    * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
    orangefs: Use RCU for destroy_inode
    vfs: use helper for calling f_op->fsync()
    mm: use helper for calling f_op->mmap()
    vfs: use helpers for calling f_op->{read,write}_iter()
    vfs: pass type instead of fn to do_{loop,iter}_readv_writev()
    vfs: extract common parts of {compat_,}do_readv_writev()
    vfs: wrap write f_ops with file_{start,end}_write()
    vfs: deny copy_file_range() for non regular files
    vfs: deny fallocate() on directory
    vfs: create vfs helper vfs_tmpfile()
    namei.c: split unlazy_walk()
    namei.c: fold the check for DCACHE_OP_REVALIDATE into d_revalidate()
    lookup_fast(): clean up the logics around the fallback to non-rcu mode
    namei: fold unlazy_link() into its sole caller

    Linus Torvalds
     

02 Mar, 2017

2 commits


28 Feb, 2017

1 commit

  • Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs
    branch.

    This patch also fixes multiple checkpatch warnings: WARNING: Prefer
    'unsigned int' to bare use of 'unsigned'

    Thanks to Andrew Morton for suggesting more appropriate function instead
    of macro.

    [geliangtang@gmail.com: truncate: use i_blocksize()]
    Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com
    Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be
    Signed-off-by: Fabian Frederick
    Signed-off-by: Geliang Tang
    Cc: Alexander Viro
    Cc: Ross Zwisler
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Fabian Frederick
     

26 Feb, 2017

1 commit


10 Feb, 2017

2 commits

  • The deamon through which the kernel module communicates with the userspace
    part of Orangefs, the "client-core", sends initialization data to the
    kernel module with ioctl. The initialization data was built by the
    client-core in a 2k buffer and copy_from_user'd into a 1k buffer
    in the kernel module. When more than 1k of initialization data needed
    to be sent, some was lost, reducing the usability of the control by which
    debug levels are set. This patch sets the kernel side buffer to 2K to
    match the userspace side...

    Signed-off-by: Mike Marshall

    Mike Marshall
     
  • This patch is simlar to one Dan Carpenter sent me, cleans
    up some return codes and whitespace errors. There was one
    place where he thought inserting an error message into
    the ring buffer might be too chatty, I hope I convinced him
    othewise. As a consolation I changed a truly chatty
    error message in another location into a debug message,
    system-admins had already yelled at me about that one...

    Signed-off-by: Mike Marshall

    Mike Marshall
     

04 Feb, 2017

3 commits

  • It is not used anywhere.

    CC: Mike Marshall
    Signed-off-by: Jan Kara
    Signed-off-by: Mike Marshall

    Jan Kara
     
  • Signed-off-by: Martin Brandenburg
    Signed-off-by: Mike Marshall

    Martin Brandenburg
     
  • The issue here is that in orangefs_bufmap_alloc() we do:

    bufmap->buffer_index_array =
    kzalloc(DIV_ROUND_UP(bufmap->desc_count, BITS_PER_LONG), GFP_KERNEL);

    If we choose a bufmap->desc_count like -31 then it means the
    DIV_ROUND_UP ends up having an integer overflow. The result is that
    kzalloc() returns the ZERO_SIZE_PTR and there is a static checker
    warning.

    But this bug is harmless because on the next lines we use ->desc_count
    to do a kcalloc(). That has integer overflow checking built in so the
    kcalloc() fails and we return an error code.

    Anyway, it doesn't make sense to talk about negative sizes and blocking
    them silences the static checker warning.

    Signed-off-by: Dan Carpenter
    Signed-off-by: Mike Marshall

    Dan Carpenter
     

18 Dec, 2016

1 commit

  • …/linux/kernel/git/mszeredi/vfs

    Pull partial readlink cleanups from Miklos Szeredi.

    This is the uncontroversial part of the readlink cleanup patch-set that
    simplifies the default readlink handling.

    Miklos and Al are still discussing the rest of the series.

    * git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
    vfs: make generic_readlink() static
    vfs: remove ".readlink = generic_readlink" assignments
    vfs: default to generic_readlink()
    vfs: replace calling i_op->readlink with vfs_readlink()
    proc/self: use generic_readlink
    ecryptfs: use vfs_get_link()
    bad_inode: add missing i_op initializers

    Linus Torvalds
     

17 Dec, 2016

1 commit

  • Pull vfs updates from Al Viro:

    - more ->d_init() stuff (work.dcache)

    - pathname resolution cleanups (work.namei)

    - a few missing iov_iter primitives - copy_from_iter_full() and
    friends. Either copy the full requested amount, advance the iterator
    and return true, or fail, return false and do _not_ advance the
    iterator. Quite a few open-coded callers converted (and became more
    readable and harder to fuck up that way) (work.iov_iter)

    - several assorted patches, the big one being logfs removal

    * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
    logfs: remove from tree
    vfs: fix put_compat_statfs64() does not handle errors
    namei: fold should_follow_link() with the step into not-followed link
    namei: pass both WALK_GET and WALK_MORE to should_follow_link()
    namei: invert WALK_PUT logics
    namei: shift interpretation of LOOKUP_FOLLOW inside should_follow_link()
    namei: saner calling conventions for mountpoint_last()
    namei.c: get rid of user_path_parent()
    switch getfrag callbacks to ..._full() primitives
    make skb_add_data,{_nocache}() and skb_copy_to_page_nocache() advance only on success
    [iov_iter] new primitives - copy_from_iter_full() and friends
    don't open-code file_inode()
    ceph: switch to use of ->d_init()
    ceph: unify dentry_operations instances
    lustre: switch to use of ->d_init()

    Linus Torvalds
     

16 Dec, 2016

1 commit