25 Mar, 2011

1 commit

  • * 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block: (65 commits)
    Documentation/iostats.txt: bit-size reference etc.
    cfq-iosched: removing unnecessary think time checking
    cfq-iosched: Don't clear queue stats when preempt.
    blk-throttle: Reset group slice when limits are changed
    blk-cgroup: Only give unaccounted_time under debug
    cfq-iosched: Don't set active queue in preempt
    block: fix non-atomic access to genhd inflight structures
    block: attempt to merge with existing requests on plug flush
    block: NULL dereference on error path in __blkdev_get()
    cfq-iosched: Don't update group weights when on service tree
    fs: assign sb->s_bdi to default_backing_dev_info if the bdi is going away
    block: Require subsystems to explicitly allocate bio_set integrity mempool
    jbd2: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
    jbd: finish conversion from WRITE_SYNC_PLUG to WRITE_SYNC and explicit plugging
    fs: make fsync_buffers_list() plug
    mm: make generic_writepages() use plugging
    blk-cgroup: Add unaccounted time to timeslice_used.
    block: fixup plugging stubs for !CONFIG_BLOCK
    block: remove obsolete comments for blkdev_issue_zeroout.
    blktrace: Use rq->cmd_flags directly in blk_add_trace_rq.
    ...

    Fix up conflicts in fs/{aio.c,super.c}

    Linus Torvalds
     

14 Mar, 2011

1 commit

  • The exportfs encode handle function should return the minimum required
    handle size. This helps user to find out the handle size by passing 0
    handle size in the first step and then redoing to the call again with
    the returned handle size value.

    Acked-by: Serge Hallyn
    Signed-off-by: Aneesh Kumar K.V
    Signed-off-by: Al Viro

    Aneesh Kumar K.V
     

10 Mar, 2011

2 commits


13 Jan, 2011

1 commit


07 Jan, 2011

5 commits

  • Require filesystems be aware of .d_revalidate being called in rcu-walk
    mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
    -ECHILD from all implementations.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • Reduce some branches and memory accesses in dcache lookup by adding dentry
    flags to indicate common d_ops are set, rather than having to check them.
    This saves a pointer memory access (dentry->d_op) in common path lookup
    situations, and saves another pointer load and branch in cases where we
    have d_op but not the particular operation.

    Patched with:

    git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • RCU free the struct inode. This will allow:

    - Subsequent store-free path walking patch. The inode must be consulted for
    permissions when walking, so an RCU inode reference is a must.
    - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
    to take i_lock no longer need to take sb_inode_list_lock to walk the list in
    the first place. This will simplify and optimize locking.
    - Could remove some nested trylock loops in dcache code
    - Could potentially simplify things a bit in VM land. Do not need to take the
    page lock to follow page->mapping.

    The downsides of this is the performance cost of using RCU. In a simple
    creat/unlink microbenchmark, performance drops by about 10% due to inability to
    reuse cache-hot slab objects. As iterations increase and RCU freeing starts
    kicking over, this increases to about 20%.

    In cases where inode lifetimes are longer (ie. many inodes may be allocated
    during the average life span of a single inode), a lot of this cache reuse is
    not applicable, so the regression caused by this patch is smaller.

    The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
    however this adds some complexity to list walking and store-free path walking,
    so I prefer to implement this at a later date, if it is shown to be a win in
    real situations. I haven't found a regression in any non-micro benchmark so I
    doubt it will be a problem.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • Change d_hash so it may be called from lock-free RCU lookups. See similar
    patch for d_compare for details.

    For in-tree filesystems, this is just a mechanical change.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • Change d_compare so it may be called from lock-free RCU lookups. This
    does put significant restrictions on what may be done from the callback,
    however there don't seem to have been any problems with in-tree fses.
    If some strange use case pops up that _really_ cannot cope with the
    rcu-walk rules, we can just add new rcu-unaware callbacks, which would
    cause name lookup to drop out of rcu-walk mode.

    For in-tree filesystems, this is just a mechanical change.

    Signed-off-by: Nick Piggin

    Nick Piggin
     

29 Oct, 2010

1 commit


23 Oct, 2010

1 commit

  • * 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block: (46 commits)
    xen-blkfront: disable barrier/flush write support
    Added blk-lib.c and blk-barrier.c was renamed to blk-flush.c
    block: remove BLKDEV_IFL_WAIT
    aic7xxx_old: removed unused 'req' variable
    block: remove the BH_Eopnotsupp flag
    block: remove the BLKDEV_IFL_BARRIER flag
    block: remove the WRITE_BARRIER flag
    swap: do not send discards as barriers
    fat: do not send discards as barriers
    ext4: do not send discards as barriers
    jbd2: replace barriers with explicit flush / FUA usage
    jbd2: Modify ASYNC_COMMIT code to not rely on queue draining on barrier
    jbd: replace barriers with explicit flush / FUA usage
    nilfs2: replace barriers with explicit flush / FUA usage
    reiserfs: replace barriers with explicit flush / FUA usage
    gfs2: replace barriers with explicit flush / FUA usage
    btrfs: replace barriers with explicit flush / FUA usage
    xfs: replace barriers with explicit flush / FUA usage
    block: pass gfp_mask and flags to sb_issue_discard
    dm: convey that all flushes are processed as empty
    ...

    Linus Torvalds
     

05 Oct, 2010

2 commits

  • The lock_kernel in fat_put_super is not needed because
    it only protects the super block itself and we know that
    no other thread can reach it because we are about to
    kfree the object.

    In the two fill_super functions, this converts the locking
    to use lock_super like elsewhere in the fat code. This
    is probably not needed either, but is consistent and puts
    us on the safe side.

    Signed-off-by: Arnd Bergmann
    Cc: OGAWA Hirofumi
    Cc: Jan Blunck

    Arnd Bergmann
     
  • This patch is a preparation necessary to remove the BKL from do_new_mount().
    It explicitly adds calls to lock_kernel()/unlock_kernel() around
    get_sb/fill_super operations for filesystems that still uses the BKL.

    I've read through all the code formerly covered by the BKL inside
    do_kern_mount() and have satisfied myself that it doesn't need the BKL
    any more.

    do_kern_mount() is already called without the BKL when mounting the rootfs
    and in nfsctl. do_kern_mount() calls vfs_kern_mount(), which is called
    from various places without BKL: simple_pin_fs(), nfs_do_clone_mount()
    through nfs_follow_mountpoint(), afs_mntpt_do_automount() through
    afs_mntpt_follow_link(). Both later functions are actually the filesystems
    follow_link inode operation. vfs_kern_mount() is calling the specified
    get_sb function and lets the filesystem do its job by calling the given
    fill_super function.

    Therefore I think it is safe to push down the BKL from the VFS to the
    low-level filesystems get_sb/fill_super operation.

    [arnd: do not add the BKL to those file systems that already
    don't use it elsewhere]

    Signed-off-by: Jan Blunck
    Signed-off-by: Arnd Bergmann
    Cc: Matthew Wilcox
    Cc: Christoph Hellwig

    Jan Blunck
     

17 Sep, 2010

1 commit

  • All the blkdev_issue_* helpers can only sanely be used for synchronous
    caller. To issue cache flushes or barriers asynchronously the caller needs
    to set up a bio by itself with a completion callback to move the asynchronous
    state machine ahead. So drop the BLKDEV_IFL_WAIT flag that is always
    specified when calling blkdev_issue_* and also remove the now unused flags
    argument to blkdev_issue_flush and blkdev_issue_zeroout. For
    blkdev_issue_discard we need to keep it for the secure discard flag, which
    gains a more descriptive name and loses the bitops vs flag confusion.

    Signed-off-by: Christoph Hellwig
    Signed-off-by: Jens Axboe

    Christoph Hellwig
     

10 Sep, 2010

3 commits


18 Aug, 2010

1 commit

  • These flags aren't real I/O types, but tell ll_rw_block to always
    lock the buffer instead of giving up on a failed trylock.

    Instead add a new write_dirty_buffer helper that implements this semantic
    and use it from the existing SWRITE* callers. Note that the ll_rw_block
    code had a bug where it didn't promote WRITE_SYNC_PLUG properly, which
    this patch fixes.

    In the ufs code clean up the helper that used to call ll_rw_block
    to mirror sync_dirty_buffer, which is the function it implements for
    compound buffers.

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

    Christoph Hellwig
     

10 Aug, 2010

6 commits

  • Signed-off-by: Al Viro

    Al Viro
     
  • Make sure we check the truncate constraints early on in ->setattr by adding
    those checks to inode_change_ok. Also clean up and document inode_change_ok
    to make this obvious.

    As a fallout we don't have to call inode_newsize_ok from simple_setsize and
    simplify it down to a truncate_setsize which doesn't return an error. This
    simplifies a lot of setattr implementations and means we use truncate_setsize
    almost everywhere. Get rid of fat_setsize now that it's trivial and mark
    ext2_setsize static to make the calling convention obvious.

    Keep the inode_newsize_ok in vmtruncate for now as all callers need an
    audit for its removal anyway.

    Note: setattr code in ecryptfs doesn't call inode_change_ok at all and
    needs a deeper audit, but that is left for later.

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

    Christoph Hellwig
     
  • Make sure we call inode_change_ok before doing any changes in ->setattr,
    and make sure to call it even if our fs wants to ignore normal UNIX
    permissions, but use the ATTR_FORCE to skip those.

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

    Christoph Hellwig
     
  • Despite its name it's now a generic implementation of ->setattr, but
    rather a helper to copy attributes from a struct iattr to the inode.
    Rename it to setattr_copy to reflect this fact.

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

    Christoph Hellwig
     
  • Move the call to vmtruncate to get rid of accessive blocks to the callers
    in preparation of the new truncate sequence and rename the non-truncating
    version to cont_write_begin.

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

    Christoph Hellwig
     
  • Move the call to vmtruncate to get rid of accessive blocks to the callers
    in prepearation of the new truncate calling sequence. This was only done
    for DIO_LOCKING filesystems, so the __blockdev_direct_IO_newtrunc variant
    was not needed anyway. Get rid of blockdev_direct_IO_no_locking and
    its _newtrunc variant while at it as just opencoding the two additional
    paramters is shorted than the name suffix.

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

    Christoph Hellwig
     

28 May, 2010

3 commits


25 May, 2010

1 commit


24 May, 2010

1 commit


17 May, 2010

1 commit

  • FAT does not require the BKL in its ioctl function, which is already serialized
    through a mutex. Since we're already touching the ioctl code, also fix the
    missing handling of FAT_IOCTL_GET_ATTRIBUTES in the compat code.

    Signed-off-by: Arnd Bergmann
    Signed-off-by: OGAWA Hirofumi

    Arnd Bergmann
     

05 Apr, 2010

1 commit


01 Apr, 2010

1 commit

  • When using the string representation of a random counter as part of the base
    name, ensure that it is no longer than 4 bytes.

    Since we are repeatedly decrementing the counter in a loop until we have found a
    unique base name, the counter may wrap around zero; therefore, it is not enough
    to mask its higher bits before entering the loop, this must be done inside the
    loop.

    [hirofumi@mail.parknet.co.jp: use snprintf()]
    Signed-off-by: Nikolaus Schulz
    Cc: stable@kernel.org
    Signed-off-by: OGAWA Hirofumi
    Signed-off-by: Linus Torvalds

    Nikolaus Schulz
     

30 Mar, 2010

1 commit

  • …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

16 Mar, 2010

2 commits


13 Mar, 2010

1 commit


06 Mar, 2010

1 commit

  • This gives the filesystem more information about the writeback that
    is happening. Trond requested this for the NFS unstable write handling,
    and other filesystems might benefit from this too by beeing able to
    distinguish between the different callers in more detail.

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

    Christoph Hellwig
     

10 Feb, 2010

1 commit

  • I found that the length of a file name when created cannot exceed 255
    characters, yet, pathconf(), via statfs(), returns the maximum as 260.

    Signed-off-by: Kevin Dankwardt
    Signed-off-by: OGAWA Hirofumi

    Kevin Dankwardt
     

12 Jan, 2010

1 commit

  • After d_find_alias(), vfat_lookup() checks !(->d_flags & DCACHE_DISCONNECTED)
    without IS_ROOT(). This means it hits non-anonymous but disconnected
    dentry. (NOTE: d_splice_alias() doesn't clear DCACHE_DISCONNECTED)

    But, vfat_lookup() has interest to alias if it was non-anonymous. So,
    this adds vfat_d_anon_disconn() helper to check it correctly.

    Another bug is refcnt leak. It needs dput() for uninterested alias.

    Signed-off-by: OGAWA Hirofumi

    OGAWA Hirofumi