Use symbolic names instead of hardcoded constants.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NHarald Welte <laforge@gnumonks.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We've had two instances recently of overflows when doing

	64_bit_value = (32_bit_value << PAGE_CACHE_SHIFT)

I did a tree-wide grep of `<<.*PAGE_CACHE_SHIFT' and this is the result.

- afs_rxfs_fetch_descriptor.offset is of type off_t, which seems broken.

- jfs and jffs are limited to 4GB anyway.

- reiserfs map_block_for_writepage() takes an unsigned long for the block -
  it should take sector_t.  (It'll fail for huge filesystems with
  blocksize<PAGE_CACHE_SIZE)

- cramfs_read() needs to use sector_t (I think cramsfs is busted on large
  filesystems anyway)

- affs is limited in file size anyway.

- I generally didn't fix 32-bit overflows in directory operations.

- arm's __flush_dcache_page() is peculiar.  What if the page lies beyond 4G?

- gss_wrap_req_priv() needs checking (snd_buf->page_base)

Cc: Oleg Drokin <green@linuxhacker.ru>
Cc: David Howells <dhowells@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: <reiserfs-dev@namesys.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

__create_workqueue() not checking return of alloc_percpu()

NULL dereference was possible.
Signed-off-by: NBen Collins <bcollins@ubuntu.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

      <stuartm@connecttech.com>

Sent by Paul Clements <paul.clements@steeleye.com>, who needs to read
Documentation/SubmittingPatches..
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

HDIO_GETGEO is implemented in most block drivers, and all of them have to
duplicate the code to copy the structure to userspace, as well as getting
the start sector.  This patch moves that to common code [1] and adds a
->getgeo method to fill out the raw kernel hd_geometry structure.  For many
drivers this means ->ioctl can go away now.

[1] the s390 block drivers are odd in this respect.  xpram sets ->start
    to 4 always which seems more than odd, and the dasd driver shifts
    the start offset around, probably because of it's non-standard
    sector size.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@suse.de>
Cc: <mike.miller@hp.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

While rooting aroung in the signal code trying to understand how to fix the
SIG_IGN ploy (set sig handler to SIG_IGN and flood system with high speed
repeating timers) I came across what, I think, is a problem in sigaction()
in that when processing a SIG_IGN request it flushes signals from 1 to
SIGRTMIN and leaves the rest.  Attempt to fix this.
Signed-off-by: NGeorge Anzinger <george@mvista.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make it possible for a running process (such as gssapid) to be able to
instantiate a key, as was requested by Trond Myklebust for NFS4.

The patch makes the following changes:

 (1) A new, optional key type method has been added. This permits a key type
     to intercept requests at the point /sbin/request-key is about to be
     spawned and do something else with them - passing them over the
     rpc_pipefs files or netlink sockets for instance.

     The uninstantiated key, the authorisation key and the intended operation
     name are passed to the method.

 (2) The callout_info is no longer passed as an argument to /sbin/request-key
     to prevent unauthorised viewing of this data using ps or by looking in
     /proc/pid/cmdline.

     This means that the old /sbin/request-key program will not work with the
     patched kernel as it will expect to see an extra argument that is no
     longer there.

     A revised keyutils package will be made available tomorrow.

 (3) The callout_info is now attached to the authorisation key. Reading this
     key will retrieve the information.

 (4) A new field has been added to the task_struct. This holds the
     authorisation key currently active for a thread. Searches now look here
     for the caller's set of keys rather than looking for an auth key in the
     lowest level of the session keyring.

     This permits a thread to be servicing multiple requests at once and to
     switch between them. Note that this is per-thread, not per-process, and
     so is usable in multithreaded programs.

     The setting of this field is inherited across fork and exec.

 (5) A new keyctl function (KEYCTL_ASSUME_AUTHORITY) has been added that
     permits a thread to assume the authority to deal with an uninstantiated
     key. Assumption is only permitted if the authorisation key associated
     with the uninstantiated key is somewhere in the thread's keyrings.

     This function can also clear the assumption.

 (6) A new magic key specifier has been added to refer to the currently
     assumed authorisation key (KEY_SPEC_REQKEY_AUTH_KEY).

 (7) Instantiation will only proceed if the appropriate authorisation key is
     assumed first. The assumed authorisation key is discarded if
     instantiation is successful.

 (8) key_validate() is moved from the file of request_key functions to the
     file of permissions functions.

 (9) The documentation is updated.

From: <Valdis.Kletnieks@vt.edu>

    Build fix.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Alexander Zangerl <az@bond.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Cause any links within a keyring to keys that match a key to be linked into
that keyring to be discarded as a link to the new key is added.  The match is
contingent on the type and description strings being the same.

This permits requests, adds and searches to displace negative, expired,
revoked and dead keys easily.  After some discussion it was concluded that
duplicate valid keys should probably be discarded also as they would otherwise
hide the new key.

Since request_key() is intended to be the primary method by which keys are
added to a keyring, duplicate valid keys wouldn't be an issue there as that
function would return an existing match in preference to creating a new key.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Alexander Zangerl <az@bond.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add a new keyctl function that allows the expiry time to be set on a key or
removed from a key, provided the caller has attribute modification access.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Alexander Zangerl <az@bond.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

kmsg_write returns with printk, so some programs may be confused by a
successful write() with a return value different than the buffer length.

# /bin/echo something > /dev/kmsg
/bin/echo: write error: Inappropriate ioctl for device

The drawbacks is that the printk return value can no more be quickly
checked from userspace.
Signed-off-by: NGuillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

What's the true meaning of the printk return value?  Should it include the
priority prefix length of 3?  and what about the timing information?  In
both cases it was broken:

strace -e write echo 1 > /dev/kmsg
=> write(1, "1\n", 2)                      = 5
strace -e write echo "<1>1" > /dev/kmsg
=> write(1, "<1>1\n", 5)                   = 8

The returned length was "length of input string + 3", I made it "length
of string output to the log buffer".

Note that I couldn't find any printk caller in the kernel interested by its
return value besides kmsg_write.
Signed-off-by: NGuillaume Chazarain <guichaz@yahoo.fr>
Acked-By: NTim Bird <tim.bird@am.sony.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When making an fctl locking call through compat_sys_fcntl64 (i.e.  a 32bit
app on a 64bit kernel), the syscall can return a locking range that is in
conflict with the queried lock.

If some aspect of this range does not fit in the 32bit structure, something
needs to be done.

The current code is wrong in several respects:

- It returns data to userspace even if no conflict was found
   i.e. it should check l_type for F_UNLCK
- It returns -EOVERFLOW too agressively.   A lock range covering
  the last possible byte of the file (start = COMPAT_OFF_T_MAX,
  len = 1) should be possible, but is rejected with the current test.
- A extra-long 'len' should not be a problem.  If only that part
  of the conflicting lock that would be visible to the 32bit
  app needs to be reported to the 32bit app anyway.

This patch addresses those three issues and adds a comment to (hopefully)
record it for posterity.

Note: this patch mainly affects test-cases.  Real applications rarely is
ever see the problems.

This patch has been tested (LSB test suite), and works.
Signed-off-by: NNeil Brown <neilb@suse.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SUS requires that when truncating a file to the size that it currently
is:
  truncate and ftruncate should NOT modify ctime or mtime
  O_TRUNC SHOULD modify ctime and mtime.

Currently mtime and ctime are always modified on most local
filesystems (side effect of ->truncate) or never modified (on NFS).

With this patch:
  ATTR_CTIME|ATTR_MTIME are sent with ATTR_SIZE precisely when
    an update of these times is required whether size changes or not
    (via a new argument to do_truncate).  This allows NFS to do
    the right thing for O_TRUNC.
  inode_setattr nolonger forces ATTR_MTIME|ATTR_CTIME when the ATTR_SIZE
    sets the size to it's current value.  This allows local filesystems
    to do the right thing for f?truncate.

Also, the logic in inode_setattr is changed a bit so there are two return
points.  One returns the error from vmtruncate if it failed, the other
returns 0 (there can be no other failure).

Finally, if vmtruncate succeeds, and ATTR_SIZE is the only change
requested, we now fall-through and mark_inode_dirty.  If a filesystem did
not have a ->truncate function, then vmtruncate will have changed i_size,
without marking the inode as 'dirty', and I think this is wrong.
Signed-off-by: NNeil Brown <neilb@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make it possible to include linux/pagevec.h multiple times without
incurring errors due to duplicate definitions.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Reported from Redhat Bugzilla Bug 170450

"I updated to the development kernel and now during boot only the top of the
text is visable. For example the monitor screen the is the lines and I can
only see text in the asterisk area.

When doublescan mode is in use, scanlines must be doubled.

Thanks to Jason Dravet <dravet@hotmail.com> for reporting and testing.
Signed-off-by: NSamuel Thibault <samuel.thibault@ens-lyon.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

inode can never be NULL when calling this function.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The ptrace_get_task_struct() helper that I added as part of the ptrace
consolidation is useful in variety of places that currently opencode it.
Switch them to the common helpers.

Add a ptrace_traceme() helper that needs to be explicitly called, and simplify
the ptrace_get_task_struct() interface.  We don't need the request argument
now, and we return the task_struct directly, using ERR_PTR() for error
returns.  It's a bit more code in the callers, but we have two sane routines
that do one thing well now.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

librelay and relay-app.h have been retired - update Documentation to reflect
that.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch renames relayfs_file_operations to relay_file_operations, and the
file operations themselves from relayfs_XXX to relay_file_XXX, to make it more
clear that they refer to relay files.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Documentation update for creating global buffers.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds the optional is_global outparam to the create_buf_file()
callback.  This can be used by clients to create a single global relayfs
buffer instead of the default per-cpu buffers.  This was suggested as being
useful for certain debugging applications where it's more convenient to be
able to get all the data from a single channel without having to go to the
bother of dealing with per-cpu files.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Documentation update for creating relay files in other filesystems.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds a couple of callback functions that allow a client to hook
into relay_open()/close() and supply the files that will be used to represent
the channel buffers; the default implementation if no callbacks are defined is
to create the files in relayfs.  This is to support the creation and use of
relay files in other filesystems such as debugfs, as implied by the fact that
relayfs_file_operations are exported.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Documentation update for non-relay files.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Since we're no longer using relayfs_inode_info, remove relayfs_alloc_inode()
and relayfs_destroy_inode() along with the relayfs inode cache.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use inode->u.generic_ip instead of relayfs_inode_info to store pointer to user
data.  Clients using relayfs_file_create() to create their own files would
probably more expect their data to be stored in generic_ip; we also intend in
the next set of patches to get rid of relayfs-specific stuff in the file
operations, so we might as well do it here.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds and exports relayfs_remove_file(), for API symmetry (with
relayfs_create_file()).
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds a mandatory fileops param to relayfs_create_file() and exports
that function so that clients can use it to create files defined by their own
set of file operations, in relayfs.  The purpose is to allow relayfs
applications to create their own set of 'control' files alongside their relay
files in relayfs rather than having to create them in /proc or debugfs for
instance.  relayfs_create_file() is also used by relay_open_buf() to create
the relay files for a channel.  In this case, a pointer to
relayfs_file_operations is passed in, along with a pointer to the buffer
associated with the file.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The patch series implementa or fixes 3 things that were specifically requested
or suggested by relayfs users:

- support for non-relay files (patches 1-6)

Currently, the relayfs API only supports the creation of directories
(relayfs_create_dir()) and relay files (relay_open()).  These patches adds
support for non-relay files (relayfs_create_file()).  This is so relayfs
applications can create 'control files' in relayfs itself rather than in /proc
or via a netlink channel, as is currently done in the relay-app examples.
Basically what this amounts to is exporting relayfs_create_file() with an
additional file_ops param that clients can use to supply file operations for
their own special-purpose files in relayfs.

- make exported relay file ops useful (patches 7-8)

The relayfs relay_file_operations have always been exported, the intent being
to make it possible to create relay files in other filesystems such as
debugfs.  The problem, though, is that currently the file operations are too
tightly coupled to relayfs to actually be used for this purpose.  This patch
fixes that by adding a couple of callback functions that allow a client to
hook into relay_open()/close() and supply the files that will be used to
represent the channel buffers; the default implementation if no callbacks are
defined is to create the files in relayfs.

- add an option to create global relay buffer (patches 9-10) The file creation
callback also supplies an optional param, is_global, that can be used by
clients to create a single global relayfs buffer instead of the default
per-cpu buffers.  This was suggested as being useful for certain debugging
applications where it's more convenient to be able to get all the data from a
single channel without having to go to the bother of dealing with per-cpu
files.

- cleanup, some renaming and Documentation updates (patches 11-12)

There were several comments that the use of netlink in the example code was
non-intuitive and in fact the whole relay-app business was needlessly
confusing.  Based on that feedback, the example code has been completely
converted over to relayfs control files as supported by this patch, and have
also been made completely self-contained.

The converted examples along with a couple of new examples that demonstrate
using exported relay files can be found in relay-apps tarball:
http://prdownloads.sourceforge.net/relayfs/relay-apps-0.9.tar.gz?download

This patch:

Separate buffer create/destroy from inode create/destroy.  We want to be able
to associate other data and not just relay buffers with inodes.  Buffer
create/destroy is moved out of inode.c and into relayfs core code.
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Unobfsucate this struct member

Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Needed for the Novell kernel debugger and perhaps some per-cpu data on x86_64
in the future.

Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use atomic_inc_not_zero for rcu files instead of special case rcuref.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Convert atomic_dec_and_lock to use new atomic primitives.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Use bd_claim() when opening the cdrom device to prevent user space programs
such as cdrecord, hald and kded from interfering with the burning process.
Signed-off-by: NPeter Osterlund <petero2@telia.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch contains the following cleanups:
- make needlessly global functions static
- every file should include the headers containing the prototypes for
  it's global functions
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Acked-by: N"Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

"extern inline" -> "static inline"

Since there's no pullphone() function this patch removes the dead
prototype.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Acked-by: NKarsten Keil <kkeil@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch moves the rtc_interrupt() prototype to rtc.h and removes the
prototypes from C files.

It also renames static rtc_interrupt() functions in
arch/arm/mach-integrator/time.c and arch/sh64/kernel/time.c to avoid compile
problems.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NPaul Gortmaker <p_gortmaker@yahoo.com>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch add EXPORT_SYMBOL(filemap_write_and_wait) and use it.

See mm/filemap.c:

And changes the filemap_write_and_wait() and filemap_write_and_wait_range().

Current filemap_write_and_wait() doesn't wait if filemap_fdatawrite()
returns error.  However, even if filemap_fdatawrite() returned an
error, it may have submitted the partially data pages to the device.
(e.g. in the case of -ENOSPC)

<quotation>
Andrew Morton writes,

If filemap_fdatawrite() returns an error, this might be due to some
I/O problem: dead disk, unplugged cable, etc.  Given the generally
crappy quality of the kernel's handling of such exceptions, there's a
good chance that the filemap_fdatawait() will get stuck in D state
forever.
</quotation>

So, this patch doesn't wait if filemap_fdatawrite() returns the -EIO.

Trond, could you please review the nfs part?  Especially I'm not sure,
nfs must use the "filemap_fdatawrite(inode->i_mapping) == 0", or not.
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>