07 Jan, 2012

1 commit


04 Jan, 2012

3 commits


02 Nov, 2011

1 commit

  • This adds a d_prune dentry operation that is called by the VFS prior to
    pruning (i.e. unhashing and killing) a hashed dentry from the dcache.
    Wrap dentry_lru_del() and use the new _prune() helper in the cases where we
    are about to unhash and kill the dentry.

    This will be used by Ceph to maintain a flag indicating whether the
    complete contents of a directory are contained in the dcache, allowing it
    to satisfy lookups and readdir without addition server communication.

    Renumber a few DCACHE_* #defines to group DCACHE_OP_PRUNE with the other
    DCACHE_OP_ bits.

    Signed-off-by: Sage Weil
    Signed-off-by: Christoph Hellwig

    Sage Weil
     

26 Jul, 2011

2 commits

  • * 'for-3.1' of git://linux-nfs.org/~bfields/linux:
    nfsd: don't break lease on CLAIM_DELEGATE_CUR
    locks: rename lock-manager ops
    nfsd4: update nfsv4.1 implementation notes
    nfsd: turn on reply cache for NFSv4
    nfsd4: call nfsd4_release_compoundargs from pc_release
    nfsd41: Deny new lock before RECLAIM_COMPLETE done
    fs: locks: remove init_once
    nfsd41: check the size of request
    nfsd41: error out when client sets maxreq_sz or maxresp_sz too small
    nfsd4: fix file leak on open_downgrade
    nfsd4: remember to put RW access on stateid destruction
    NFSD: Added TEST_STATEID operation
    NFSD: added FREE_STATEID operation
    svcrpc: fix list-corrupting race on nfsd shutdown
    rpc: allow autoloading of gss mechanisms
    svcauth_unix.c: quiet sparse noise
    svcsock.c: include sunrpc.h to quiet sparse noise
    nfsd: Remove deprecated nfsctl system call and related code.
    NFSD: allow OP_DESTROY_CLIENTID to be only op in COMPOUND

    Fix up trivial conflicts in Documentation/feature-removal-schedule.txt

    Linus Torvalds
     
  • Replace the ->check_acl method with a ->get_acl method that simply reads an
    ACL from disk after having a cache miss. This means we can replace the ACL
    checking boilerplate code with a single implementation in namei.c.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Al Viro

    Christoph Hellwig
     

21 Jul, 2011

2 commits

  • Btrfs needs to be able to control how filemap_write_and_wait_range() is called
    in fsync to make it less of a painful operation, so push down taking i_mutex and
    the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some
    file systems can drop taking the i_mutex altogether it seems, like ext3 and
    ocfs2. For correctness sake I just pushed everything down in all cases to make
    sure that we keep the current behavior the same for everybody, and then each
    individual fs maintainer can make up their mind about what to do from there.
    Thanks,

    Acked-by: Jan Kara
    Signed-off-by: Josef Bacik
    Signed-off-by: Al Viro

    Josef Bacik
     
  • Both the filesystem and the lock manager can associate operations with a
    lock. Confusingly, one of them (fl_release_private) actually has the
    same name in both operation structures.

    It would save some confusion to give the lock-manager ops different
    names.

    Signed-off-by: J. Bruce Fields

    J. Bruce Fields
     

20 Jul, 2011

1 commit


27 May, 2011

1 commit

  • Tell the filesystem if we just updated timestamp (I_DIRTY_SYNC) or
    anything else, so that the filesystem can track internally if it
    needs to push out a transaction for fdatasync or not.

    This is just the prototype change with no user for it yet. I plan
    to push large XFS changes for the next merge window, and getting
    this trivial infrastructure in this window would help a lot to avoid
    tree interdependencies.

    Also remove incorrect comments that ->dirty_inode can't block. That
    has been changed a long time ago, and many implementations rely on it.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Al Viro

    Christoph Hellwig
     

25 Mar, 2011

1 commit

  • Now that inode state changes are protected by the inode->i_lock and
    the inode LRU manipulations by the inode_lru_lock, we can remove the
    inode_lock from prune_icache and the initial part of iput_final().

    instead of using the inode_lock to protect the inode during
    iput_final, use the inode->i_lock instead. This protects the inode
    against new references being taken while we change the inode state
    to I_FREEING, as well as preventing prune_icache from grabbing the
    inode while we are manipulating it. Hence we no longer need the
    inode_lock in iput_final prior to setting I_FREEING on the inode.

    For prune_icache, we no longer need the inode_lock to protect the
    LRU list, and the inodes themselves are protected against freeing
    races by the inode->i_lock. Hence we can lift the inode_lock from
    prune_icache as well.

    Signed-off-by: Dave Chinner
    Signed-off-by: Al Viro

    Dave Chinner
     

17 Mar, 2011

1 commit


17 Jan, 2011

2 commits

  • Currently all filesystems except XFS implement fallocate asynchronously,
    while XFS forced a commit. Both of these are suboptimal - in case of O_SYNC
    I/O we really want our allocation on disk, especially for the !KEEP_SIZE
    case where we actually grow the file with user-visible zeroes. On the
    other hand always commiting the transaction is a bad idea for fast-path
    uses of fallocate like for example in recent Samba versions. Given
    that block allocation is a data plane operation anyway change it from
    an inode operation to a file operation so that we have the file structure
    available that lets us check for O_SYNC.

    This also includes moving the code around for a few of the filesystems,
    and remove the already unnedded S_ISDIR checks given that we only wire
    up fallocate for regular files.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Al Viro

    Christoph Hellwig
     
  • * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (23 commits)
    sanitize vfsmount refcounting changes
    fix old umount_tree() breakage
    autofs4: Merge the remaining dentry ops tables
    Unexport do_add_mount() and add in follow_automount(), not ->d_automount()
    Allow d_manage() to be used in RCU-walk mode
    Remove a further kludge from __do_follow_link()
    autofs4: Bump version
    autofs4: Add v4 pseudo direct mount support
    autofs4: Fix wait validation
    autofs4: Clean up autofs4_free_ino()
    autofs4: Clean up dentry operations
    autofs4: Clean up inode operations
    autofs4: Remove unused code
    autofs4: Add d_manage() dentry operation
    autofs4: Add d_automount() dentry operation
    Remove the automount through follow_link() kludge code from pathwalk
    CIFS: Use d_automount() rather than abusing follow_link()
    NFS: Use d_automount() rather than abusing follow_link()
    AFS: Use d_automount() rather than abusing follow_link()
    Add an AT_NO_AUTOMOUNT flag to suppress terminal automount
    ...

    Linus Torvalds
     

16 Jan, 2011

3 commits

  • Allow d_manage() to be called from pathwalk when it is in RCU-walk mode as well
    as when it is in Ref-walk mode. This permits __follow_mount_rcu() to call
    d_manage() directly. d_manage() needs a parameter to indicate that it is in
    RCU-walk mode as it isn't allowed to sleep if in that mode (but should return
    -ECHILD instead).

    autofs4_d_manage() can then be set to retain RCU-walk mode if the daemon
    accesses it and otherwise request dropping back to ref-walk mode.

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

    David Howells
     
  • Add a dentry op (d_manage) to permit a filesystem to hold a process and make it
    sleep when it tries to transit away from one of that filesystem's directories
    during a pathwalk. The operation is keyed off a new dentry flag
    (DCACHE_MANAGE_TRANSIT).

    The filesystem is allowed to be selective about which processes it holds and
    which it permits to continue on or prohibits from transiting from each flagged
    directory. This will allow autofs to hold up client processes whilst letting
    its userspace daemon through to maintain the directory or the stuff behind it
    or mounted upon it.

    The ->d_manage() dentry operation:

    int (*d_manage)(struct path *path, bool mounting_here);

    takes a pointer to the directory about to be transited away from and a flag
    indicating whether the transit is undertaken by do_add_mount() or
    do_move_mount() skipping through a pile of filesystems mounted on a mountpoint.

    It should return 0 if successful and to let the process continue on its way;
    -EISDIR to prohibit the caller from skipping to overmounted filesystems or
    automounting, and to use this directory; or some other error code to return to
    the user.

    ->d_manage() is called with namespace_sem writelocked if mounting_here is true
    and no other locks held, so it may sleep. However, if mounting_here is true,
    it may not initiate or wait for a mount or unmount upon the parameter
    directory, even if the act is actually performed by userspace.

    Within fs/namei.c, follow_managed() is extended to check with d_manage() first
    on each managed directory, before transiting away from it or attempting to
    automount upon it.

    follow_down() is renamed follow_down_one() and should only be used where the
    filesystem deliberately intends to avoid management steps (e.g. autofs).

    A new follow_down() is added that incorporates the loop done by all other
    callers of follow_down() (do_add/move_mount(), autofs and NFSD; whilst AFS, NFS
    and CIFS do use it, their use is removed by converting them to use
    d_automount()). The new follow_down() calls d_manage() as appropriate. It
    also takes an extra parameter to indicate if it is being called from mount code
    (with namespace_sem writelocked) which it passes to d_manage(). follow_down()
    ignores automount points so that it can be used to mount on them.

    __follow_mount_rcu() is made to abort rcu-walk mode if it hits a directory with
    DCACHE_MANAGE_TRANSIT set on the basis that we're probably going to have to
    sleep. It would be possible to enter d_manage() in rcu-walk mode too, and have
    that determine whether to abort or not itself. That would allow the autofs
    daemon to continue on in rcu-walk mode.

    Note that DCACHE_MANAGE_TRANSIT on a directory should be cleared when it isn't
    required as every tranist from that directory will cause d_manage() to be
    invoked. It can always be set again when necessary.

    ==========================
    WHAT THIS MEANS FOR AUTOFS
    ==========================

    Autofs currently uses the lookup() inode op and the d_revalidate() dentry op to
    trigger the automounting of indirect mounts, and both of these can be called
    with i_mutex held.

    autofs knows that the i_mutex will be held by the caller in lookup(), and so
    can drop it before invoking the daemon - but this isn't so for d_revalidate(),
    since the lock is only held on _some_ of the code paths that call it. This
    means that autofs can't risk dropping i_mutex from its d_revalidate() function
    before it calls the daemon.

    The bug could manifest itself as, for example, a process that's trying to
    validate an automount dentry that gets made to wait because that dentry is
    expired and needs cleaning up:

    mkdir S ffffffff8014e05a 0 32580 24956
    Call Trace:
    [] :autofs4:autofs4_wait+0x674/0x897
    [] avc_has_perm+0x46/0x58
    [] autoremove_wake_function+0x0/0x2e
    [] :autofs4:autofs4_expire_wait+0x41/0x6b
    [] :autofs4:autofs4_revalidate+0x91/0x149
    [] __lookup_hash+0xa0/0x12f
    [] lookup_create+0x46/0x80
    [] sys_mkdirat+0x56/0xe4

    versus the automount daemon which wants to remove that dentry, but can't
    because the normal process is holding the i_mutex lock:

    automount D ffffffff8014e05a 0 32581 1 32561
    Call Trace:
    [] __mutex_lock_slowpath+0x60/0x9b
    [] do_path_lookup+0x2ca/0x2f1
    [] .text.lock.mutex+0xf/0x14
    [] do_rmdir+0x77/0xde
    [] tracesys+0x71/0xe0
    [] tracesys+0xd5/0xe0

    which means that the system is deadlocked.

    This patch allows autofs to hold up normal processes whilst the daemon goes
    ahead and does things to the dentry tree behind the automouter point without
    risking a deadlock as almost no locks are held in d_manage() and none in
    d_automount().

    Signed-off-by: David Howells
    Was-Acked-by: Ian Kent
    Signed-off-by: Al Viro

    David Howells
     
  • Add a dentry op (d_automount) to handle automounting directories rather than
    abusing the follow_link() inode operation. The operation is keyed off a new
    dentry flag (DCACHE_NEED_AUTOMOUNT).

    This also makes it easier to add an AT_ flag to suppress terminal segment
    automount during pathwalk and removes the need for the kludge code in the
    pathwalk algorithm to handle directories with follow_link() semantics.

    The ->d_automount() dentry operation:

    struct vfsmount *(*d_automount)(struct path *mountpoint);

    takes a pointer to the directory to be mounted upon, which is expected to
    provide sufficient data to determine what should be mounted. If successful, it
    should return the vfsmount struct it creates (which it should also have added
    to the namespace using do_add_mount() or similar). If there's a collision with
    another automount attempt, NULL should be returned. If the directory specified
    by the parameter should be used directly rather than being mounted upon,
    -EISDIR should be returned. In any other case, an error code should be
    returned.

    The ->d_automount() operation is called with no locks held and may sleep. At
    this point the pathwalk algorithm will be in ref-walk mode.

    Within fs/namei.c itself, a new pathwalk subroutine (follow_automount()) is
    added to handle mountpoints. It will return -EREMOTE if the automount flag was
    set, but no d_automount() op was supplied, -ELOOP if we've encountered too many
    symlinks or mountpoints, -EISDIR if the walk point should be used without
    mounting and 0 if successful. The path will be updated to point to the mounted
    filesystem if a successful automount took place.

    __follow_mount() is replaced by follow_managed() which is more generic
    (especially with the patch that adds ->d_manage()). This handles transits from
    directories during pathwalk, including automounting and skipping over
    mountpoints (and holding processes with the next patch).

    __follow_mount_rcu() will jump out of RCU-walk mode if it encounters an
    automount point with nothing mounted on it.

    follow_dotdot*() does not handle automounts as you don't want to trigger them
    whilst following "..".

    I've also extracted the mount/don't-mount logic from autofs4 and included it
    here. It makes the mount go ahead anyway if someone calls open() or creat(),
    tries to traverse the directory, tries to chdir/chroot/etc. into the directory,
    or sticks a '/' on the end of the pathname. If they do a stat(), however,
    they'll only trigger the automount if they didn't also say O_NOFOLLOW.

    I've also added an inode flag (S_AUTOMOUNT) so that filesystems can mark their
    inodes as automount points. This flag is automatically propagated to the
    dentry as DCACHE_NEED_AUTOMOUNT by __d_instantiate(). This saves NFS and could
    save AFS a private flag bit apiece, but is not strictly necessary. It would be
    preferable to do the propagation in d_set_d_op(), but that doesn't normally
    have access to the inode.

    [AV: fixed breakage in case if __follow_mount_rcu() fails and nameidata_drop_rcu()
    succeeds in RCU case of do_lookup(); we need to fall through to non-RCU case after
    that, rather than just returning with ungrabbed *path]

    Signed-off-by: David Howells
    Was-Acked-by: Ian Kent
    Signed-off-by: Al Viro

    David Howells
     

15 Jan, 2011

1 commit

  • * 'for-2.6.38' of git://linux-nfs.org/~bfields/linux: (62 commits)
    nfsd4: fix callback restarting
    nfsd: break lease on unlink, link, and rename
    nfsd4: break lease on nfsd setattr
    nfsd: don't support msnfs export option
    nfsd4: initialize cb_per_client
    nfsd4: allow restarting callbacks
    nfsd4: simplify nfsd4_cb_prepare
    nfsd4: give out delegations more quickly in 4.1 case
    nfsd4: add helper function to run callbacks
    nfsd4: make sure sequence flags are set after destroy_session
    nfsd4: re-probe callback on connection loss
    nfsd4: set sequence flag when backchannel is down
    nfsd4: keep finer-grained callback status
    rpc: allow xprt_class->setup to return a preexisting xprt
    rpc: keep backchannel xprt as long as server connection
    rpc: move sk_bc_xprt to svc_xprt
    nfsd4: allow backchannel recovery
    nfsd4: support BIND_CONN_TO_SESSION
    nfsd4: modify session list under cl_lock
    Documentation: fl_mylease no longer exists
    ...

    Fix up conflicts in fs/nfsd/vfs.c with the vfs-scale work. The
    vfs-scale work touched some msnfs cases, and this merge removes support
    for that entirely, so the conflict was trivial to resolve.

    Linus Torvalds
     

12 Jan, 2011

1 commit


07 Jan, 2011

5 commits


05 Jan, 2011

1 commit


31 Dec, 2010

1 commit


02 Dec, 2010

1 commit

  • NFS needs to be able to release objects that are stored in the page
    cache once the page itself is no longer visible from the page cache.

    This patch adds a callback to the address space operations that allows
    filesystems to perform page cleanups once the page has been removed
    from the page cache.

    Original patch by: Linus Torvalds
    [trondmy: cover the cases of invalidate_inode_pages2() and
    truncate_inode_pages()]
    Signed-off-by: Trond Myklebust

    Linus Torvalds
     

31 Oct, 2010

1 commit


26 Oct, 2010

1 commit


14 Aug, 2010

1 commit


10 Aug, 2010

1 commit


28 May, 2010

2 commits


11 May, 2010

1 commit

  • Replace the introduced i_sem by an i_mutex in the filesystem locking
    documentation. This was introduced [1] after all occurrences were
    already replaced in the same text [2]. However, the term "inode
    semaphore" has not been replaced then, and it's replaced now.

    [1] afddba49d18f346e5cc2938b6ed7c512db18ca68
    [2] a7bc02f4f47fd0e7860c6589f0ad000d1476f7a3

    Signed-off-by: Thadeu Lima de Souza Cascardo
    Cc: Nick Piggin
    Cc: Artem Bityutskiy
    Cc: Randy Dunlap
    Cc: Christoph Hellwig
    Cc: Al Viro
    Signed-off-by: Jiri Kosina

    Thadeu Lima de Souza Cascardo
     

05 Mar, 2010

5 commits

  • Get rid of the initialize dquot operation - it is now always called from
    the filesystem and if a filesystem really needs it's own (which none
    currently does) it can just call into it's own routine directly.

    Rename the now static low-level dquot_initialize helper to __dquot_initialize
    and vfs_dq_init to dquot_initialize to have a consistent namespace.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Jan Kara

    Christoph Hellwig
     
  • Get rid of the drop dquot operation - it is now always called from
    the filesystem and if a filesystem really needs it's own (which none
    currently does) it can just call into it's own routine directly.

    Rename the now static low-level dquot_drop helper to __dquot_drop
    and vfs_dq_drop to dquot_drop to have a consistent namespace.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Jan Kara

    Christoph Hellwig
     
  • Get rid of the transfer dquot operation - it is now always called from
    the filesystem and if a filesystem really needs it's own (which none
    currently does) it can just call into it's own routine directly.

    Rename the now static low-level dquot_transfer helper to __dquot_transfer
    and vfs_dq_transfer to dquot_transfer to have a consistent namespace,
    and make the new dquot_transfer return a normal negative errno value
    which all callers expect.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Jan Kara

    Christoph Hellwig
     
  • Get rid of the alloc_inode and free_inode dquot operations - they are
    always called from the filesystem and if a filesystem really needs
    their own (which none currently does) it can just call into it's
    own routine directly.

    Also get rid of the vfs_dq_alloc/vfs_dq_free wrappers and always
    call the lowlevel dquot_alloc_inode / dqout_free_inode routines
    directly, which now lose the number argument which is always 1.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Jan Kara

    Christoph Hellwig
     
  • Get rid of the alloc_space, free_space, reserve_space, claim_space and
    release_rsv dquot operations - they are always called from the filesystem
    and if a filesystem really needs their own (which none currently does)
    it can just call into it's own routine directly.

    Move shared logic into the common __dquot_alloc_space,
    dquot_claim_space_nodirty and __dquot_free_space low-level methods,
    and rationalize the wrappers around it to move as much as possible
    code into the common block for CONFIG_QUOTA vs not. Also rename
    all these helpers to be named dquot_* instead of vfs_dq_*.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Jan Kara

    Christoph Hellwig