Commit Graph

8910 Commits

Author SHA1 Message Date
Jeff Moyer
9d2de6ad2a autofs4: fix incorrect return from root.c:try_to_fill_dentry()
Jeff Moyer has identified a case where the autofs4 function
root.c:try_to_fill_dentry() can return -EBUSY when it should return 0.

Jeff's description of the way this happens is:

"automount starts an expire for directory d.  after the callout to the daemon,
but before the rmdir, another process tries to walk into the same directory.
It puts itself onto the waitq, pending the expiration.

When the expire finishes, the second process is woken up.  In
try_to_fill_dentry, it does this check:

                status = d_invalidate(dentry);
                if (status != -EBUSY)
                        return -EAGAIN;

And status is EBUSY.  The dentry still has a non-zero d_inode, and the
flags do not contain LOOKUP_CONTINUE or LOOKUP_DIRECTORY

So, we fall through and return -EBUSY to the caller."

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:04:01 -07:00
Jeff Moyer
033790449b autofs4: fix execution order race in mount request code
Jeff Moyer has identified a race in due to an execution order dependency
in the autofs4 function root.c:try_to_fill_dentry().

Jeff's description of this race is:

"P1 does a lookup of /mount/submount/foo.  Since the VFS can't find an entry
for "foo" under /mount/submount, it calls into the autofs4 kernel module to
allocate a new dentry, D1.  The kernel creates a new waitq for this lookup and
calls the daemon to perform the mount.

The daemon performs a mkdir of the "foo" directory under /mount/submount,
which ends up creating a *new* dentry, D2.

Then, P2 does a lookup of /mount/submount/foo.  The VFS path walking logic
finds a dentry in the dcache, D2, and calls the revalidate function with this.
 In the autofs4 revalidate code, we then trigger a mount, since the dentry is
an empty directory that isn't a mountpoint, and so set DCACHE_AUTOFS_PENDING
and call into the wait code to trigger the mount.

The wait code finds our existing waitq entry (since it is keyed off of the
directory name) and adds itself to the list of waiters.

After the daemon finishes the mount, it calls back into the kernel to release
the waiters.  When this happens, P1 is woken up and goes about clearing the
DCACHE_AUTOFS_PENDING flag, but it does this in D1!  So, given that P1 in our
case is a program that will immediately try to access a file under
/mount/submount/foo, we end up finding the dentry D2 which still has the
pending flag set, and we set out to wait for a mount *again*!

So, one way to address this is to re-do the lookup at the end of
try_to_fill_dentry, and to clear the pending flag on the hashed dentry.  This
seems a sane approach to me."

And Jeff's patch does this.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:04:01 -07:00
Ian Kent
cab0936aac autofs4: check for invalid dentry in getpath
Catch invalid dentry when calculating its path.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:04:01 -07:00
Ian Kent
afec570c32 autofs4: fix sparse warning in waitq.c:autofs4_expire_indirect()
Re-order some code in expire.c:autofs4_expire_indirect() to avoid compile
warning, reported by Harvey Harrison:

 CHECK   fs/autofs4/expire.c
fs/autofs4/expire.c:383:2: warning: context imbalance in
'autofs4_expire_indirect' - unexpected unlock

Signed-off-by: Ian Kent <raven@themaw.net>
Reviewed-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:04:01 -07:00
Miklos Szeredi
02c6be615f vfs: fix permission checking in sys_utimensat
If utimensat() is called with both times set to UTIME_NOW or one of them to
UTIME_NOW and the other to UTIME_OMIT, then it will update the file time
without any permission checking.

I don't think this can be used for anything other than a local DoS, but could
be quite bewildering at that (e.g.  "Why was that large source tree rebuilt
when I didn't modify anything???")

This affects all kernels from 2.6.22, when the utimensat() syscall was
introduced.

Fix by doing the same permission checking as for the "times == NULL" case.

Thanks to Michael Kerrisk, whose utimensat-non-conformances-and-fixes.patch in
-mm also fixes this (and breaks other stuff), only he didn't realize the
security implications of this bug.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:03:59 -07:00
Al Viro
214b7049a7 Fix dnotify/close race
We have a race between fcntl() and close() that can lead to
dnotify_struct inserted into inode's list *after* the last descriptor
had been gone from current->files.

Since that's the only point where dnotify_struct gets evicted, we are
screwed - it will stick around indefinitely.  Even after struct file in
question is gone and freed.  Worse, we can trigger send_sigio() on it at
any later point, which allows to send an arbitrary signal to arbitrary
process if we manage to apply enough memory pressure to get the page
that used to host that struct file and fill it with the right pattern...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 20:09:00 -07:00
Robert P. J. Day
883ce42ec4 DEBUGFS: Correct location of debugfs API documentation.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-30 16:52:47 -07:00
Ben Hutchings
40a2159abf sysfs: Disallow truncation of files in sysfs
sysfs allows attribute files to be truncated, e.g. using ftruncate(), with the
expected effect on their inode.   For most attributes, this doesn't change the
"real" size of the file i.e. how much can be read from it.  However, the
parameter validation for reading and writing binary attribute files is based
on the inode size and not the size specified in the file's bin_attribute, so it
can be broken by this. For example, if we try using dd to write to such a file:

# pwd
/sys/bus/pci/devices/0000:08:00.0
# ls -l config
-rw-r--r--  1 root root 4096 Feb  1 17:35 config
# dd if=/dev/zero of=config bs=4 count=1
1+0 records in
1+0 records out
# ls -l config
-rw-r--r--  1 root root 0 Feb  1 17:50 config
# dd if=/dev/zero of=config bs=4 count=1 seek=128
dd: writing `config': No space left on device
1+0 records in
0+0 records out

Also, after truncation to 0, parameter validation for read and write is
disabled.  Most bin_attribute read and write methods also validate the size and
offset, but for some this will allow out-of-range access.  This may be a
security issue, though access to such files is often limited to root.  In any
case, the validation should remain for safety's sake!)

This was previously reported in Bugzilla as bug 9867.

sysfs should ignore size changes or else refuse them (by returning -EINVAL).
This patch makes it ignore them.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-30 16:52:46 -07:00
Linus Torvalds
d67c6f869c Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
  [S390] Update default configuration.
  [S390] use generic sys_ptrace
  [S390] Remove self ptrace IEEE_IP hack.
  [S390] Convert to SPARSEMEM & SPARSEMEM_VMEMMAP
  [S390] System z large page support.
  [S390] Convert machine feature detection code to C.
  [S390] vmemmap: use clear_table to initialise page tables.
  [S390] Move stfl to system.h and delete duplicated version.
  [S390] uaccess_mvcos: #ifdef config dependent code.
  [S390] cpu topology: Fix possible deadlock.
  [S390] Add topology_core_siblings to topology.h
  [S390] cio: Make isc handling more robust.
  [S390] remove -traditional
  [S390] Automatically detect added cpus.
  [S390] smp: Fix locking order.
  [S390] Add missing ifndef/define to include/asm-s390/sysinfo.h.
  [S390] Move show_regs to traps.c.
  [S390] cio: Use strict_strtoul() for attributes.
2008-04-30 08:38:30 -07:00
Harvey Harrison
8e24eea728 fs: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:54 -07:00
Harvey Harrison
530b641278 afs: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:54 -07:00
Thomas Gleixner
c6f3a97f86 debugobjects: add timer specific object debugging code
Add calls to the generic object debugging infrastructure and provide fixup
functions which allow to keep the system alive when recoverable problems have
been detected by the object debugging core code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:53 -07:00
Andrew Morton
487798df6d hfsplus: fix warning with 64k PAGE_SIZE
fs/hfsplus/btree.c: In function 'hfsplus_bmap_alloc':
fs/hfsplus/btree.c:239: warning: comparison is always false due to limited range of data type

But this might hide a real bug?

Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:52 -07:00
Andrew Morton
3e5a509730 hfs: fix warning with 64k PAGE_SIZE
fs/hfs/btree.c: In function 'hfs_bmap_alloc':
fs/hfs/btree.c:263: warning: comparison is always false due to limited range of data type

The patch makes the warning go away, but the code might actually be buggy?

Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:52 -07:00
Marcin Slusarz
07132922aa sysv: [bl]e*_add_cpu conversion
replace all:
big/little_endian_variable = cpu_to_[bl]eX([bl]eX_to_cpu(big/little_endian_variable) +
					expression_in_cpu_byteorder);
with:
	[bl]eX_add_cpu(&big/little_endian_variable, expression_in_cpu_byteorder);
generated with semantic patch

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:52 -07:00
Marcin Slusarz
e3592b12f5 quota: le*_add_cpu conversion
replace all:
little_endian_variable = cpu_to_leX(leX_to_cpu(little_endian_variable) +
					expression_in_cpu_byteorder);
with:
	leX_add_cpu(&little_endian_variable, expression_in_cpu_byteorder);
generated with semantic patch

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Marcin Slusarz
20c79e785a hfs/hfsplus: be*_add_cpu conversion
replace all:
big_endian_variable = cpu_to_beX(beX_to_cpu(big_endian_variable) +
					expression_in_cpu_byteorder);
with:
	beX_add_cpu(&big_endian_variable, expression_in_cpu_byteorder);
generated with semantic patch

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Marcin Slusarz
6369a4abb4 affs: be*_add_cpu conversion
replace all:
big_endian_variable = cpu_to_beX(beX_to_cpu(big_endian_variable) +
					expression_in_cpu_byteorder);
with:
	beX_add_cpu(&big_endian_variable, expression_in_cpu_byteorder);
generated with semantic patch

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Christoph Hellwig
86098fa011 reiserfs: use open_bdev_excl
Use the proper helper to open a blockdevice by name for filesystem use,
this makes sure it's properly claimed (also added for open-by-number) and
gets rid of the struct file abuse.

Tested by mounting a reiserfs filesystem with external journal.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Acked-by: Edward Shishkin <edward.shishkin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Miklos Szeredi
4dbf930ed6 fuse: fix sparse warnings
fs/fuse/dev.c:306:2: warning: context imbalance in 'wait_answer_interruptible' - unexpected unlock
fs/fuse/dev.c:361:2: warning: context imbalance in 'request_wait_answer' - unexpected unlock
fs/fuse/dev.c:1002:4: warning: context imbalance in 'end_io_requests' - unexpected unlock

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Miklos Szeredi
5559b8f4d1 fuse: fix race in llseek
Fuse doesn't use i_mutex to protect setting i_size, and so
generic_file_llseek() can be racy: it doesn't use i_size_read().

So do a fuse specific llseek method, which does use i_size_read().

[akpm@linux-foundation.org: make `retval' loff_t]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Miklos Szeredi
b48badf013 fuse: fix node ID type
Node ID is 64bit but it is passed as unsigned long to some functions.  This
breakage wasn't noticed, because libfuse uses unsigned long too.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Miklos Szeredi
e5d9a0df07 fuse: fix max i/o size calculation
Fix a bug that Werner Baumann reported: fuse can send a bigger write request
than the maximum specified.  This only affected direct_io operation.

In addition set a sane minimum for the max_read and max_write tunables, so I/O
always makes some progress.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:51 -07:00
Miklos Szeredi
5c5c5e51b2 fuse: update file size on short read
If the READ request returned a short count, then either

  - cached size is incorrect
  - filesystem is buggy, as short reads are only allowed on EOF

So assume that the size is wrong and refresh it, so that cached read() doesn't
zero fill the missing chunk.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Nick Piggin
ea9b9907b8 fuse: implement perform_write
Introduce fuse_perform_write.  With fusexmp (a passthrough filesystem), large
(1MB) writes into a backing tmpfs filesystem are sped up by almost 4 times
(256MB/s vs 71MB/s).

[mszeredi@suse.cz]:

 - split into smaller functions
 - testing
 - duplicate generic_file_aio_write(), so that there's no need to add a
   new ->perform_write() a_op.  Comment from hch.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Miklos Szeredi
854512ec35 fuse: clean up setting i_size in write
Extract common code for setting i_size in write functions into a common
helper.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Miklos Szeredi
3be5a52b30 fuse: support writable mmap
Quoting Linus (3 years ago, FUSE inclusion discussions):

  "User-space filesystems are hard to get right. I'd claim that they
   are almost impossible, unless you limit them somehow (shared
   writable mappings are the nastiest part - if you don't have those,
   you can reasonably limit your problems by limiting the number of
   dirty pages you accept through normal "write()" calls)."

Instead of attempting the impossible, I've just waited for the dirty page
accounting infrastructure to materialize (thanks to Peter Zijlstra and
others).  This nicely solved the biggest problem: limiting the number of pages
used for write caching.

Some small details remained, however, which this largish patch attempts to
address.  It provides a page writeback implementation for fuse, which is
completely safe against VM related deadlocks.  Performance may not be very
good for certain usage patterns, but generally it should be acceptable.

It has been tested extensively with fsx-linux and bash-shared-mapping.

Fuse page writeback design
--------------------------

fuse_writepage() allocates a new temporary page with GFP_NOFS|__GFP_HIGHMEM.
It copies the contents of the original page, and queues a WRITE request to the
userspace filesystem using this temp page.

The writeback is finished instantly from the MM's point of view: the page is
removed from the radix trees, and the PageDirty and PageWriteback flags are
cleared.

For the duration of the actual write, the NR_WRITEBACK_TEMP counter is
incremented.  The per-bdi writeback count is not decremented until the actual
write completes.

On dirtying the page, fuse waits for a previous write to finish before
proceeding.  This makes sure, there can only be one temporary page used at a
time for one cached page.

This approach is wasteful in both memory and CPU bandwidth, so why is this
complication needed?

The basic problem is that there can be no guarantee about the time in which
the userspace filesystem will complete a write.  It may be buggy or even
malicious, and fail to complete WRITE requests.  We don't want unrelated parts
of the system to grind to a halt in such cases.

Also a filesystem may need additional resources (particularly memory) to
complete a WRITE request.  There's a great danger of a deadlock if that
allocation may wait for the writepage to finish.

Currently there are several cases where the kernel can block on page
writeback:

  - allocation order is larger than PAGE_ALLOC_COSTLY_ORDER
  - page migration
  - throttle_vm_writeout (through NR_WRITEBACK)
  - sync(2)

Of course in some cases (fsync, msync) we explicitly want to allow blocking.
So for these cases new code has to be added to fuse, since the VM is not
tracking writeback pages for us any more.

As an extra safetly measure, the maximum dirty ratio allocated to a single
fuse filesystem is set to 1% by default.  This way one (or several) buggy or
malicious fuse filesystems cannot slow down the rest of the system by hogging
dirty memory.

With appropriate privileges, this limit can be raised through
'/sys/class/bdi/<bdi>/max_ratio'.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Miklos Szeredi
fc3ba692a4 mm: Add NR_WRITEBACK_TEMP counter
Fuse will use temporary buffers to write back dirty data from memory mappings
(normal writes are done synchronously).  This is needed, because there cannot
be any guarantee about the time in which a write will complete.

By using temporary buffers, from the MM's point if view the page is written
back immediately.  If the writeout was due to memory pressure, this
effectively migrates data from a full zone to a less full zone.

This patch adds a new counter (NR_WRITEBACK_TEMP) for the number of pages used
as temporary buffers.

[Lee.Schermerhorn@hp.com: add vmstat_text for NR_WRITEBACK_TEMP]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Miklos Szeredi
e4ad08fe64 mm: bdi: add separate writeback accounting capability
Add a new BDI capability flag: BDI_CAP_NO_ACCT_WB.  If this flag is
set, then don't update the per-bdi writeback stats from
test_set_page_writeback() and test_clear_page_writeback().

Misc cleanups:

 - convert bdi_cap_writeback_dirty() and friends to static inline functions
 - create a flag that includes all three dirty/writeback related flags,
   since almst all users will want to have them toghether

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:50 -07:00
Miklos Szeredi
b6f2fcbcfc mm: bdi: expose the BDI object in sysfs for FUSE
Register FUSE's backing_dev_info under sysfs with the name "fuse-MAJOR:MINOR"

Make the fuse control filesystem use s_dev instead of a fuse specific ID.
This makes it easier to match directories under /sys/fs/fuse/connections/ with
directories under /sys/class/bdi, and with actual mounts.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:49 -07:00
Miklos Szeredi
fa799759f9 mm: bdi: expose the BDI object in sysfs for NFS
Register NFS' backing_dev_info under sysfs with the name "nfs-MAJOR:MINOR"

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:49 -07:00
Sukadev Bhattiprolu
718a916338 devpts: factor out PTY index allocation
Factor out the code used to allocate/free a pts index into new interfaces,
devpts_new_index() and devpts_kill_index().  This localizes the external data
structures used in managing the pts indices.

[akpm@linux-foundation.org: undo accidental mutex2sem conversion]
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:48 -07:00
Alan Cox
f34d7a5b70 tty: The big operations rework
- Operations are now a shared const function block as with most other Linux
  objects

- Introduce wrappers for some optional functions to get consistent behaviour

- Wrap put_char which used to be patched by the tty layer

- Document which functions are needed/optional

- Make put_char report success/fail

- Cache the driver->ops pointer in the tty as tty->ops

- Remove various surplus lock calls we no longer need

- Remove proc_write method as noted by Alexey Dobriyan

- Introduce some missing sanity checks where certain driver/ldisc
  combinations would oops as they didn't check needed methods were present

[akpm@linux-foundation.org: fix fs/compat_ioctl.c build]
[akpm@linux-foundation.org: fix isicom]
[akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build]
[akpm@linux-foundation.org: fix kgdb]
Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:47 -07:00
Alan Cox
5d0fdf1e01 tty_io: fix remaining pid struct locking
This fixes the last couple of pid struct locking failures I know about.

[oleg@tv-sign.ru: clean up do_task_stat()]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:40 -07:00
Alan Cox
04f378b198 tty: BKL pushdown
- Push the BKL down into the line disciplines
- Switch the tty layer to unlocked_ioctl
- Introduce a new ctrl_lock spin lock for the control bits
- Eliminate much of the lock_kernel use in n_tty
- Prepare to (but don't yet) call the drivers with the lock dropped
  on the paths that historically held the lock

BKL now primarily protects open/close/ldisc change in the tty layer

[jirislaby@gmail.com: a couple of fixes]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:40 -07:00
Oleg Nesterov
2800d8d19e document de_thread() with exit_notify() connection
Add a couple of small comments, it is not easy to see what this code does.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:38 -07:00
Roland McGrath
f3de272b82 signals: use HAVE_SET_RESTORE_SIGMASK
Change all the #ifdef TIF_RESTORE_SIGMASK conditionals in non-arch code to
#ifdef HAVE_SET_RESTORE_SIGMASK.  If arch code defines it first, the generic
set_restore_sigmask() using TIF_RESTORE_SIGMASK is not defined.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:37 -07:00
Roland McGrath
4e4c22c711 signals: add set_restore_sigmask
This adds the set_restore_sigmask() inline in <linux/thread_info.h> and
replaces every set_thread_flag(TIF_RESTORE_SIGMASK) with a call to it.  No
change, but abstracts the details of the flag protocol from all the calls.

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:37 -07:00
Oleg Nesterov
7a5e873f09 signals: de_thread: simplify the ->child_reaper switching
Now that we rely on SIGNAL_UNKILLABLE flag, de_thread() doesn't need the nasty
hack to kill the old ->child_reaper during the mt-exec.

This also means we can avoid taking tasklist_lock around zap_other_threads().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:37 -07:00
Oleg Nesterov
06fffb1267 do_task_stat: don't take rcu_read_lock()
lock_task_sighand() was changed, and do_task_stat() doesn't need
rcu_read_lock any longer.  sighand->siglock protects all "interesting"
fields.

Except: it doesn't protect ->tty->pgrp, but neither does rcu_read_lock(), this
should be fixed.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Pavel Emelyanov <xemul@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:34 -07:00
Jan Kara
2deb1acc65 isofs: fix access to unallocated memory when reading corrupted filesystem
When a directory on isofs is corrupted, we did not check whether length of the
name in a directory entry and the length of the directory entry itself are
consistent.  This could lead to possible access beyond the end of buffer when
the length of the name was too big.  Add this sanity check to directory
reading code.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:33 -07:00
David Chinner
64275ea4f3 [XFS] Include linux/random.h in all builds, not just debug.
Noted-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Dave Chinner <dgc@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 07:53:50 -07:00
Gerald Schaefer
53492b1de4 [S390] System z large page support.
This adds hugetlbfs support on System z, using both hardware large page
support if available and software large page emulation on older hardware.
Shared (large) page tables are implemented in software emulation mode,
by using page->index of the first tail page from a compound large page
to store page table information.

Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-04-30 13:38:47 +02:00
Linus Torvalds
c4755d16fc Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (48 commits)
  ext4: fix hot spins in mballoc after err_freebuddy and err_freemeta
  ext4: fix test ext_generic_write_end() copied return value
  ext3: fix test ext_generic_write_end() copied return value
  ext4: Move mballoc headers/structures to a seperate header file mballoc.h
  ext4: cleanup for compiling mballoc with verification and debugging #defines
  ext4: don't use ext4_error in ext4_check_descriptors
  ext4: mark inode dirty after initializing the extent tree
  ext4: update ctime and mtime for truncate with extents.
  ext4: Don't do GFP_NOFS allocations after taking ext4_lock_group
  ext4: move headers out of include/linux
  ext4: fix wrong gfp type under transaction
  ext4: Fix hang on umount with quotas when journal is aborted
  ext4: Fix update of mtime and ctime on rename
  jdb2: replace remaining __FUNCTION__ occurrences
  ext4: replace remaining __FUNCTION__ occurrences
  jbd2: only create debugfs and stats entries if init is successful
  jbd2: fix kernel-doc notation
  jbd2: replace potentially false assertion with if block
  jbd2: eliminate duplicated code in revocation table init/destroy functions
  jbd2: tidy up revoke cache initialisation and destruction
  ...
2008-04-29 20:34:49 -07:00
Linus Torvalds
c15a2434ed Merge branch 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6
* 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6: (24 commits)
  [XFS] Fix build failure after enabling CONFIG_XFS_DEBUG
  [XFS] remove dmapi cruft in xfs_file.c
  [XFS] remove sendfile leftovers
  [XFS] allow enabling CONFIG_XFS_DEBUG
  [XFS] Don't initialise new inode generation numbers to zero
  [XFS] Fix check for block zero access in xfs_write_iomap_allocate()
  [XFS] Don't double count reserved block changes on UP.
  [XFS] remove xfs_log_ticket_zone on rmmod
  [XFS] fix non-smp xfs build
  [XFS] Fix broken HAVE_SPLICE removal commit.
  [XFS] kill XFS_ICSB_SB_LOCKED
  [XFS] split xfs_icsb_balance_counter
  [XFS] Add xfs_icsb_sync_counters_locked for when m_sb_lock already held
  [XFS] Cleanup xfs_attr a bit with xfs_name and remove cred
  [XFS] kill usesless IHOLD calls in xfs_remove and xfs_rmdir
  [XFS] kill parent == child checks in xfs_remove and xfs_rmdir
  [XFS] kill usesless IHOLD calls in xfs_rename
  [XFS] remove manual lookup from xfs_rename and simplify locking
  [XFS] shrink mrlock_t
  [XFS] simplify xfs_lookup
  ...
2008-04-29 20:34:17 -07:00
Roel Kluin
f1fa3342e2 ext4: fix hot spins in mballoc after err_freebuddy and err_freemeta
In ext4_mb_init_backend() 'i' is of type ext4_group_t. Since unsigned, i
>= 0 is always true, so fix hot spins after err_freebuddy: and -meta:
and prevent decrements when zero.

Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-04-29 22:01:15 -04:00
Roel Kluin
f8a87d8930 ext4: fix test ext_generic_write_end() copied return value
'copied' is unsigned, whereas 'ret2' is not. The test (copied < 0) fails

Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-04-29 22:01:18 -04:00
Roel Kluin
7c2f3d6f89 ext3: fix test ext_generic_write_end() copied return value
'copied' is unsigned, whereas 'ret2' is not. The test (copied < 0) fails

Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-04-29 22:01:27 -04:00
Mingming Cao
8f6e39a7ad ext4: Move mballoc headers/structures to a seperate header file mballoc.h
Move function and structure definiations out of mballoc.c and put it under
a new header file mballoc.h

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-04-29 22:01:31 -04:00
Solofo Ramangalahy
60bd63d192 ext4: cleanup for compiling mballoc with verification and debugging #defines
This patch allows compiling mballoc with:
#define AGGRESSIVE_CHECK
#define DOUBLE_CHECK
#define MB_DEBUG

It fixes:
Compilation errors:
fs/ext4/mballoc.c: In function '__mb_check_buddy':
fs/ext4/mballoc.c:605: error: 'struct ext4_prealloc_space' has no member named 'group_list'
fs/ext4/mballoc.c:606: error: 'struct ext4_prealloc_space' has no member named 'pstart'
fs/ext4/mballoc.c:608: error: 'struct ext4_prealloc_space' has no member named 'len'

Compilation warnings:
fs/ext4/mballoc.c: In function 'ext4_mb_normalize_group_request':
fs/ext4/mballoc.c:2863: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'int'
fs/ext4/mballoc.c: In function 'ext4_mb_use_inode_pa':
fs/ext4/mballoc.c:3103: warning: format '%lu' expects type 'long unsigned int', but argument 3 has type 'int'

Sparse check:
fs/ext4/mballoc.c:3818:2: warning: context imbalance in 'ext4_mb_show_ac' - different lock contexts for basic block

Signed-off-by: Solofo Ramangalahy <Solofo.Ramangalahy@bull.net>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-04-29 21:59:59 -04:00