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  1. 02 11月, 2011 1 次提交
  3. 23 7月, 2011 1 次提交
    • J
      isofs: Remove global fs lock · d769b3c2
      由 Jan Kara 提交于 
      sbi->s_mutex isn't needed for isofs at all so we can just remove it. Generally,
since isofs is always mounted read-only, filesystem structure cannot change
under us.  So buffer_head contents stays constant after it's filled in. That
leaves us with possible changes of global data structures. Superblock changes
only during filesystem mount (even remount does not change it), inodes are only
filled in during reading from disk. So there are no changes of these structures
to bother about.

Arguments why sbi->s_mutex can be removed at each place:
isofs_readdir: Accesses sb, inode, filp, local variables => s_mutex not needed
isofs_lookup: Protected by directory's i_mutex. Accesses sb, inode, dentry,
  local variables => s_mutex not needed
rock_ridge_symlink_readpage: Protected by page lock. Accesses sb, inode,
  local variables => s_mutex not needed.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      d769b3c2
  5. 18 6月, 2011 1 次提交
  7. 10 3月, 2011 1 次提交
  9. 13 1月, 2011 1 次提交
  11. 07 1月, 2011 4 次提交
    • N
      fs: dcache reduce branches in lookup path · fb045adb
      由 Nick Piggin 提交于 
      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: NNick Piggin <npiggin@kernel.dk>
      fb045adb
    • N
      fs: icache RCU free inodes · fa0d7e3d
      由 Nick Piggin 提交于 
      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: NNick Piggin <npiggin@kernel.dk>
      fa0d7e3d
    • N
      fs: change d_hash for rcu-walk · b1e6a015
      由 Nick Piggin 提交于 
      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: NNick Piggin <npiggin@kernel.dk>
      b1e6a015
    • N
      fs: change d_compare for rcu-walk · 621e155a
      由 Nick Piggin 提交于 
      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: NNick Piggin <npiggin@kernel.dk>
      621e155a
  13. 29 10月, 2010 1 次提交
  15. 28 10月, 2010 1 次提交
  17. 26 10月, 2010 1 次提交
    • J
      isofs: Fix isofs_get_blocks for 8TB files · fde214d4
      由 Jan Kara 提交于 
      Currently isofs_get_blocks() was limited to handle only 4TB files on 32-bit
architectures because of unnecessary use of iblock variable which was signed
long. Just remove the variable. The error messages that were using this
variable should have rather used b_off anyway because that is the block we
are currently mapping.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      fde214d4
  19. 05 10月, 2010 2 次提交
    • A
      BKL: Remove BKL from isofs · 4f819a78
      由 Arnd Bergmann 提交于 
      As in other file systems, we can replace the big kernel lock
with a private mutex in isofs. This means we can now access
multiple file systems concurrently, but it also means that
we serialize readdir and lookup across sleeping operations
which previously released the big kernel lock. This should
not matter though, as these operations are in practice
serialized through the hardware access.

The isofs_get_blocks functions now does not take any lock
any more, it used to recursively get the BKL. After looking
at the code for hours, I convinced myself that it was never
needed here anyway, because it only reads constant fields
of the inode and writes to a buffer head array that is
at this time only visible to the caller.

The get_sb and fill_super operations do not need the locking
at all because they operate on a file system that is either
about to be created or to be destroyed but in either case
is not visible to other threads.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      4f819a78
    • J
      BKL: Explicitly add BKL around get_sb/fill_super · db719222
      由 Jan Blunck 提交于 
      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: NJan Blunck <jblunck@infradead.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Christoph Hellwig <hch@infradead.org>
      db719222
  21. 11 8月, 2010 1 次提交
    • J
      isofs: Fix lseek() to position beyond 4 GB · 66a362a2
      由 Jan Andres 提交于 
      isofs supports files larger than 4 GB by using multi-extent files.
However an lseek() to a position beyond 4 GB in such a file will
fail with EINVAL, because s_maxbytes in the isofs superblock is
initialized to 2^32-1, and generic_file_llseek() checks against
that value.

I therefore suggest increasing the value of s_maxbytes to have
full support for large files in isofs. With multi-extent files, file
size is only limited by the maximum size of the file system (8 TB),
so this seems a reasonable value for s_maxbytes.
Signed-off-by: NJan Andres <jandres@gmx.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      66a362a2
  23. 24 9月, 2009 1 次提交
    • T
      fs: Make unload_nls() NULL pointer safe · 6d729e44
      由 Thomas Gleixner 提交于 
      Most call sites of unload_nls() do:
	if (nls)
		unload_nls(nls);

Check the pointer inside unload_nls() like we do in kfree() and
simplify the call sites.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Steve French <sfrench@us.ibm.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      6d729e44
  25. 11 7月, 2009 1 次提交
  27. 19 6月, 2009 3 次提交
  29. 12 6月, 2009 1 次提交
    • C
      push BKL down into ->put_super · 6cfd0148
      由 Christoph Hellwig 提交于 
      Move BKL into ->put_super from the only caller.  A couple of
filesystems had trivial enough ->put_super (only kfree and NULLing of
s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs,
hugetlbfs, omfs, qnx4, shmem, all others got the full treatment.  Most
of them probably don't need it, but I'd rather sort that out individually.
Preferably after all the other BKL pushdowns in that area.

[AV: original used to move lock_super() down as well; these changes are
removed since we don't do lock_super() at all in generic_shutdown_super()
now]
[AV: fuse, btrfs and xfs are known to need no damn BKL, exempt]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      6cfd0148
  31. 03 4月, 2009 1 次提交
  33. 28 3月, 2009 1 次提交
  35. 06 1月, 2009 1 次提交
  37. 14 10月, 2008 1 次提交
  39. 27 7月, 2008 1 次提交
  41. 09 2月, 2008 2 次提交
  43. 08 2月, 2008 1 次提交
  45. 20 10月, 2007 1 次提交
  47. 17 10月, 2007 1 次提交
  49. 01 8月, 2007 1 次提交
    • K
      isofs: mounting to regular file may succeed · 817794e0
      由 Kirill Kuvaldin 提交于 
      It turned out that mounting a corrupted ISO image to a regular file may
succeed, e.g.  if an image was prepared as follows:

$ dd if=correct.iso of=bad.iso bs=4k count=8

We then can mount it to a regular file:

# mount -o loop -t iso9660 bad.iso /tmp/file

But mounting it to a directory fails with -ENOTDIR, simply because
the root directory inode doesn't have S_IFDIR set and the condition
in graft_tree() is met:

	if (S_ISDIR(nd->dentry->d_inode->i_mode) !=
	      S_ISDIR(mnt->mnt_root->d_inode->i_mode))
		return -ENOTDIR

This is because the root directory inode was read from an incorrect
block. It's supposed to be read from sbi->s_firstdatazone, which is
an absolute value and gets messed up in the case of an incorrect image.

In order to somehow circumvent this we have to check that the root
directory inode is actually a directory after all.
Signed-off-by: NKirill Kuvaldin <kuvkir@epsmu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      817794e0
  51. 20 7月, 2007 1 次提交
    • P
      mm: Remove slab destructors from kmem_cache_create(). · 20c2df83
      由 Paul Mundt 提交于 
      Slab destructors were no longer supported after Christoph's
c59def9f change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
      20c2df83
  53. 17 7月, 2007 2 次提交
  55. 17 5月, 2007 1 次提交
    • C
      Remove SLAB_CTOR_CONSTRUCTOR · a35afb83
      由 Christoph Lameter 提交于 
      SLAB_CTOR_CONSTRUCTOR is always specified. No point in checking it.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@ucw.cz>
Cc: David Chinner <dgc@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a35afb83
  57. 08 5月, 2007 1 次提交
    • C
      slab allocators: Remove SLAB_DEBUG_INITIAL flag · 50953fe9
      由 Christoph Lameter 提交于 
      I have never seen a use of SLAB_DEBUG_INITIAL.  It is only supported by
SLAB.

I think its purpose was to have a callback after an object has been freed
to verify that the state is the constructor state again?  The callback is
performed before each freeing of an object.

I would think that it is much easier to check the object state manually
before the free.  That also places the check near the code object
manipulation of the object.

Also the SLAB_DEBUG_INITIAL callback is only performed if the kernel was
compiled with SLAB debugging on.  If there would be code in a constructor
handling SLAB_DEBUG_INITIAL then it would have to be conditional on
SLAB_DEBUG otherwise it would just be dead code.  But there is no such code
in the kernel.  I think SLUB_DEBUG_INITIAL is too problematic to make real
use of, difficult to understand and there are easier ways to accomplish the
same effect (i.e.  add debug code before kfree).

There is a related flag SLAB_CTOR_VERIFY that is frequently checked to be
clear in fs inode caches.  Remove the pointless checks (they would even be
pointless without removeal of SLAB_DEBUG_INITIAL) from the fs constructors.

This is the last slab flag that SLUB did not support.  Remove the check for
unimplemented flags from SLUB.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      50953fe9
  59. 13 2月, 2007 1 次提交
  61. 08 12月, 2006 2 次提交