Chuck Lever [Wed, 11 Jul 2012 20:30:32 +0000 (16:30 -0400)]
NFS: nfs_getaclargs.acl_len is a size_t
Squelch compiler warnings:
fs/nfs/nfs4proc.c: In function ‘__nfs4_get_acl_uncached’:
fs/nfs/nfs4proc.c:3811:14: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]
fs/nfs/nfs4proc.c:3818:15: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]
Introduced by commit bf118a34 "NFSv4: include bitmap in nfsv4 get
acl data", Dec 7, 2011.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Chuck Lever [Wed, 11 Jul 2012 20:30:14 +0000 (16:30 -0400)]
NFS: Clean up nfs41_check_expired_stateid()
Clean up: Instead of open-coded flag manipulation, use test_bit() and
clear_bit() just like all other accessors of the state->flag field.
This also eliminates several unnecessary implicit integer type
conversions.
To make it absolutely clear what is going on, a number of comments
are introduced.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Chuck Lever [Wed, 11 Jul 2012 20:30:05 +0000 (16:30 -0400)]
NFS: State reclaim clears OPEN and LOCK state
The "state->flags & flags" test in nfs41_check_expired_stateid()
allows the state manager to squelch a TEST_STATEID operation when
it is known for sure that a state ID is no longer valid. If the
lease was purged, for example, the client already knows that state
ID is now defunct.
But open recovery is still needed for that inode.
To force a call to nfs4_open_expired(), change the default return
value for nfs41_check_expired_stateid() to force open recovery, and
the default return value for nfs41_check_locks() to force lock
recovery, if the requested flags are clear. Fix suggested by Bryan
Schumaker.
Also, the presence of a delegation state ID must not prevent normal
open recovery. The delegation state ID must be cleared if it was
revoked, but once cleared I don't think it's presence or absence has
any bearing on whether open recovery is still needed. So the logic
is adjusted to ignore the TEST_STATEID result for the delegation
state ID.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Chuck Lever [Wed, 11 Jul 2012 20:29:56 +0000 (16:29 -0400)]
NFS: Don't free a state ID the server does not recognize
The result of a TEST_STATEID operation can indicate a few different
things:
o If NFS_OK is returned, then the client can continue using the
state ID under test, and skip recovery.
o RFC 5661 says that if the state ID was revoked, then the client
must perform an explicit FREE_STATEID before trying to re-open.
o If the server doesn't recognize the state ID at all, then no
FREE_STATEID is needed, and the client can immediately continue
with open recovery.
Let's err on the side of caution: if the server clearly tells us the
state ID is unknown, we skip the FREE_STATEID. For any other error,
we issue a FREE_STATEID. Sometimes that FREE_STATEID will be
unnecessary, but leaving unused state IDs on the server needlessly
ties up resources.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Chuck Lever [Wed, 11 Jul 2012 20:29:45 +0000 (16:29 -0400)]
NFS: Fix up TEST_STATEID and FREE_STATEID return code handling
The TEST_STATEID and FREE_STATEID operations can return
-NFS4ERR_BAD_STATEID, -NFS4ERR_OLD_STATEID, or -NFS4ERR_DEADSESSION.
nfs41_{test,free}_stateid() should not pass these errors to
nfs4_handle_exception() during state recovery, since that will
recursively kick off state recovery again, resulting in a deadlock.
In particular, when the TEST_STATEID operation returns NFS4_OK,
res.status can contain one of these errors. _nfs41_test_stateid()
replaces NFS4_OK with the value in res.status, which is then returned
to callers.
But res.status is not passed through nfs4_stat_to_errno(), and thus is
a positive NFS4ERR value. Currently callers are only interested in
!NFS4_OK, and nfs4_handle_exception() ignores positive values.
Thus the res.status values are currently ignored by
nfs4_handle_exception() and won't cause the deadlock above. Thanks to
this missing negative, it is only when these operations fail (which
is very rare) that a deadlock can occur.
Bryan agrees the original intent was to return res.status as a
negative NFS4ERR value to callers of nfs41_test_stateid().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Andy Adamson [Wed, 20 Jun 2012 19:03:34 +0000 (15:03 -0400)]
NFSv4.1 do not send LAYOUTRETURN on emtpy plh_segs list
mark_matching_lsegs_invalid() resets the mds_threshold counters and can
dereference the layout hdr on an initial empty plh_segs list. It returns 0 both
in the case of an initial empty list and in a non-emtpy list that was cleared
by calls to mark_lseg_invalid.
Don't send a LAYOUTRETURN if the list was initially empty.
Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Andy Adamson [Wed, 20 Jun 2012 19:03:33 +0000 (15:03 -0400)]
NFSv4.1 mark layout when already returned
When the file layout driver is fencing a DS, _pnfs_return_layout can be
called mulitple times per inode due to in-flight i/o referencing lsegs on it's
plh_segs list.
Remember that LAYOUTRETURN has been called, and do not call it again.
Allow LAYOUTRETURNs after a subsequent LAYOUTGET.
Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Andy Adamson [Wed, 20 Jun 2012 19:03:31 +0000 (15:03 -0400)]
NFSv4.1 return the LAYOUT for each file with failed DS connection I/O
First mark the deviceid invalid to prevent any future use. Then fence all
files involved in I/O to a DS with a connection error by sending a
LAYOUTRETURN.
Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
David Howells [Mon, 25 Jun 2012 11:55:37 +0000 (12:55 +0100)]
VFS: Pass mount flags to sget()
Pass mount flags to sget() so that it can use them in initialising a new
superblock before the set function is called. They could also be passed to the
compare function.
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
David Howells [Mon, 25 Jun 2012 11:55:18 +0000 (12:55 +0100)]
VFS: Make clone_mnt()/copy_tree()/collect_mounts() return errors
copy_tree() can theoretically fail in a case other than ENOMEM, but always
returns NULL which is interpreted by callers as -ENOMEM. Change it to return
an explicit error.
Also change clone_mnt() for consistency and because union mounts will add new
error cases.
Thanks to Andreas Gruenbacher <agruen@suse.de> for a bug fix.
[AV: folded braino fix by Dan Carpenter]
Original-author: Valerie Aurora <vaurora@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Valerie Aurora <valerie.aurora@gmail.com> Cc: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a helper that abstracts out the jump to an already parsed struct path
from ->follow_link operation from procfs. Not only does this clean up
the code by moving the two sides of this game into a single helper, but
it also prepares for making struct nameidata private to namei.c
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Currently the non-nd_set_link based versions of ->follow_link are expected
to do a path_put(&nd->path) on failure. This calling convention is unexpected,
undocumented and doesn't match what the nd_set_link-based instances do.
Move the path_put out of the only non-nd_set_link based ->follow_link
instance into the caller.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro [Thu, 14 Jun 2012 23:01:42 +0000 (03:01 +0400)]
get rid of kern_path_parent()
all callers want the same thing, actually - a kinda-sorta analog of
kern_path_create(). I.e. they want parent vfsmount/dentry (with
->i_mutex held, to make sure the child dentry is still their child)
+ the child dentry.
David Howells [Thu, 14 Jun 2012 15:13:46 +0000 (16:13 +0100)]
VFS: Fix the banner comment on lookup_open()
Since commit 197e37d9, the banner comment on lookup_open() no longer matches
what the function returns. It used to return a struct file pointer or NULL and
now it returns an integer and is passed the struct file pointer it is to use
amongst its arguments. Update the comment to reflect this.
Also add a banner comment to atomic_open().
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro [Sun, 10 Jun 2012 21:13:09 +0000 (17:13 -0400)]
stop passing nameidata to ->lookup()
Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument. And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...
Al Viro [Fri, 22 Jun 2012 08:40:19 +0000 (12:40 +0400)]
kill struct opendata
Just pass struct file *. Methods are happier that way...
There's no need to return struct file * from finish_open() now,
so let it return int. Next: saner prototypes for parts in
namei.c
Miklos Szeredi [Tue, 5 Jun 2012 13:10:21 +0000 (15:10 +0200)]
nfs: don't use intents for checking atomic open
is_atomic_open() is now only used by nfs4_lookup_revalidate() to check whether
it's okay to skip normal revalidation.
It does a racy check for mount read-onlyness and falls back to normal
revalidation if the open would fail. This makes little sense now that this
function isn't used for determining whether to actually open the file or not.
The d_mountpoint() check still makes sense since it is an indication that we
might be following a mount and so open may not revalidate the dentry.
Miklos Szeredi [Tue, 5 Jun 2012 13:10:19 +0000 (15:10 +0200)]
nfs: clean up ->create in nfs_rpc_ops
Don't pass nfs_open_context() to ->create(). Only the NFS4 implementation
needed that and only because it wanted to return an open file using open
intents. That task has been replaced by ->atomic_open so it is not necessary
anymore to pass the context to the create rpc operation.
Despite nfs4_proc_create apparently being okay with a NULL context it Oopses
somewhere down the call chain. So allocate a context here.
Miklos Szeredi [Tue, 5 Jun 2012 13:10:17 +0000 (15:10 +0200)]
vfs: add i_op->atomic_open()
Add a new inode operation which is called on the last component of an open.
Using this the filesystem can look up, possibly create and open the file in one
atomic operation. If it cannot perform this (e.g. the file type turned out to
be wrong) it may signal this by returning NULL instead of an open struct file
pointer.
i_op->atomic_open() is only called if the last component is negative or needs
lookup. Handling cached positive dentries here doesn't add much value: these
can be opened using f_op->open(). If the cached file turns out to be invalid,
the open can be retried, this time using ->atomic_open() with a fresh dentry.
For now leave the old way of using open intents in lookup and revalidate in
place. This will be removed once all the users are converted.
David Howells noticed that if ->atomic_open() opens the file but does not create
it, handle_truncate() will be called on it even if it is not a regular file.
Fix this by checking the file type in this case too.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro [Sun, 10 Jun 2012 08:15:17 +0000 (04:15 -0400)]
namei.c: let follow_link() do put_link() on failure
no need for kludgy "set cookie to ERR_PTR(...) because we failed
before we did actual ->follow_link() and want to suppress put_link()",
no pointless check in put_link() itself.
Callers checked if follow_link() has failed anyway; might as well
break out of their loops if that happened, without bothering
to call put_link() first.
Al Viro [Sat, 9 Jun 2012 15:55:20 +0000 (11:55 -0400)]
vfs: update documentation on ->i_dentry handling
we used to need to clean it in RCU callback freeing an inode;
in 3.2 that requirement went away. Unfortunately, it hadn't
been reflected in Documentation/filesystems/porting.
Al Viro [Sat, 9 Jun 2012 05:16:59 +0000 (01:16 -0400)]
get rid of magic in proc_namespace.c
don't rely on proc_mounts->m being the first field; container_of()
is there for purpose. No need to bother with ->private, while
we are at it - the same container_of will do nicely.
Al Viro [Sat, 9 Jun 2012 04:59:08 +0000 (00:59 -0400)]
get rid of ->mnt_longterm
it's enough to set ->mnt_ns of internal vfsmounts to something
distinct from all struct mnt_namespace out there; then we can
just use the check for ->mnt_ns != NULL in the fast path of
mntput_no_expire()
Julia Lawall [Thu, 7 Jun 2012 22:45:00 +0000 (15:45 -0700)]
fs/direct-io.c: adjust suspicious bit operation
READ is 0, so the result of the bit-and operation is 0. Rewrite with == as
done elsewhere in the same file.
This problem was found using Coccinelle (http://coccinelle.lip6.fr/).
Signed-off-by: Julia Lawall <julia@diku.dk> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch makes affs stop using the VFS '->write_super()' method along with
the 's_dirt' superblock flag, because they are on their way out.
The whole "superblock write-out" VFS infrastructure is served by the
'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and
writes out all dirty superblocks using the '->write_super()' call-back. But the
problem with this thread is that it wastes power by waking up the system every
5 seconds, even if there are no diry superblocks, or there are no client
file-systems which would need this (e.g., btrfs does not use
'->write_super()'). So we want to kill it completely and thus, we need to make
file-systems to stop using the '->write_super()' VFS service, and then remove
it together with the kernel thread.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add an 'sb' VFS superblock back-reference to the 'struct affs_sb_info' data
structure - we will need to find the VFS superblock from a 'struct
affs_sb_info' object in the next patch, so this change is jut a preparation.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The VFS's 'lock_super()' and 'unlock_super()' calls are deprecated and unwanted
and just wait for a brave knight who'd kill them. This patch makes AFFS stop
using them and use the buffer-head's own lock instead.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
AFFS wants to serialize the superblock (the root block in AFFS terms) updates
and uses 'lock_super()/unlock_super()' for these purposes. This patch pushes the
locking down to the 'affs_commit_super()' from the callers.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
affs: remove useless superblock writeout on remount
We do not need to write out the superblock from '->remount_fs()' because
VFS has already called '->sync_fs()' by this time and the superblock has
already been written out. Thus, remove the 'affs_write_super()'
infocation from 'affs_remount()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
affs: remove useless superblock writeout on unmount
We do not need to write out the superblock from '->put_super()' because VFS has
already called '->sync_fs()' by this time and the superblock has already been
written out. Thus, remove the 'affs_commit_super()' infocation from
'affs_put_super()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
AFFS stores values '1' and '2' in 'bm_flags', and I fail to see any logic when
it prefers one or another. AFFS writes '1' only from '->put_super()', while
'->sync_fs()' and '->write_super()' store value '2'. So on the first glance,
it looks like we want to have '1' if we unmount. However, this does not really
happen in these cases:
1. superblock is written via 'write_super()' then we unmount;
2. we re-mount R/O, then unmount.
which are quite typical.
I could not find good documentation describing this field, except of one random
piece of documentation in the internet which says that -1 means that the root
block is valid, which is not consistent with what we have in the Linux AFFS
driver.
Jan Kara commented on this: "I have some vague recollection that on Amiga
boolean was usually encoded as: 0 == false, ~0 == -1 == true. But it has been
ages..."
Thus, my conclusion is that value of '1' is as good as value of '2' and we can
just always use '2'. An Jan Kara suggested to go further: "generally bm_flags
handling looks strange. If they are 0, we mount fs read only and thus cannot
change them. If they are != 0, we write 2 there. So IMHO if you just removed
bm_flags setting, nothing will really happen."
So this patch removes the bm_flags setting completely. This makes the "clean"
argument of the 'affs_commit_super()' function unneeded, so it is also removed.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull the leap second fixes from Thomas Gleixner:
"It's a rather large series, but well discussed, refined and reviewed.
It got a massive testing by John, Prarit and tip.
In theory we could split it into two parts. The first two patches
are merely preventing the stuff loops forever issues, which people
have observed.
But there is no point in delaying the other 4 commits which achieve
full correctness into 3.6 as they are tagged for stable anyway. And I
rather prefer to have the full fixes merged in bulk than a "prevent
the observable wreckage and deal with the hidden fallout later"
approach."
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimer: Update hrtimer base offsets each hrtimer_interrupt
timekeeping: Provide hrtimer update function
hrtimers: Move lock held region in hrtimer_interrupt()
timekeeping: Maintain ktime_t based offsets for hrtimers
timekeeping: Fix leapsecond triggered load spike issue
hrtimer: Provide clock_was_set_delayed()
Will Drewry [Fri, 13 Jul 2012 17:06:35 +0000 (12:06 -0500)]
x86/vsyscall: allow seccomp filter in vsyscall=emulate
If a seccomp filter program is installed, older static binaries and
distributions with older libc implementations (glibc 2.13 and earlier)
that rely on vsyscall use will be terminated regardless of the filter
program policy when executing time, gettimeofday, or getcpu. This is
only the case when vsyscall emulation is in use (vsyscall=emulate is the
default).
This patch emulates system call entry inside a vsyscall=emulate by
populating regs->ax and regs->orig_ax with the system call number prior
to calling into seccomp such that all seccomp-dependencies function
normally. Additionally, system call return behavior is emulated in line
with other vsyscall entrypoints for the trace/trap cases.
[ v2: fixed ip and sp on SECCOMP_RET_TRAP/TRACE (thanks to luto@mit.edu) ] Reported-and-tested-by: Owen Kibel <qmewlo@gmail.com> Signed-off-by: Will Drewry <wad@chromium.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'nfs-for-3.5-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
- Fix an NFSv4 mount regression
- Fix O_DIRECT list manipulation snafus
* tag 'nfs-for-3.5-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Fix an NFSv4 mount regression
NFS: Fix list manipulation snafus in fs/nfs/direct.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input layer fixes from Dmitry Torokhov:
"The changes are limited to adding new VID/PID combinations to drivers
to enable support for new versions of hardware, most notably hardware
found in new MacBook Pro Retina boxes."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: xpad - add Andamiro Pump It Up pad
Input: xpad - add signature for Razer Onza Tournament Edition
Input: xpad - handle all variations of Mad Catz Beat Pad
Input: bcm5974 - Add support for 2012 MacBook Pro Retina
HID: add support for 2012 MacBook Pro Retina
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab:
- Some regression fixes at the audio part for devices with
cx23885/cx25840
- A DMA corruption fix at cx231xx
- two fixes at the winbond IR driver
- Several fixes for the EXYNOS media driver (s5p)
- two fixes at the OMAP3 preview driver
- one fix at the dvb core failure path
- an include missing (slab.h) at smiapp-core causing compilation
breakage
- em28xx was not loading the IR driver driver anymore.
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (31 commits)
[media] Revert "[media] V4L: JPEG class documentation corrections"
[media] s5p-fimc: Add missing FIMC-LITE file operations locking
[media] omap3isp: preview: Fix contrast and brightness handling
[media] omap3isp: preview: Fix output size computation depending on input format
[media] winbond-cir: Initialise timeout, driver_type and allowed_protos
[media] winbond-cir: Fix txandrx module info
[media] cx23885: Silence unknown command warnings
[media] cx23885: add support for HVR-1255 analog (cx23888 variant)
[media] cx23885: make analog support work for HVR_1250 (cx23885 variant)
[media] cx25840: fix vsrc/hsrc usage on cx23888 designs
[media] cx25840: fix regression in HVR-1800 analog audio
[media] cx25840: fix regression in analog support hue/saturation controls
[media] cx25840: fix regression in HVR-1800 analog support
[media] s5p-mfc: Fixed setup of custom controls in decoder and encoder
[media] cx231xx: don't DMA to random addresses
[media] em28xx: fix em28xx-rc load
[media] dvb-core: Release semaphore on error path dvb_register_device()
[media] s5p-fimc: Stop media entity pipeline if fimc_pipeline_validate fails
[media] s5p-fimc: Fix compiler warning in fimc-lite.c
[media] s5p-fimc: media_entity_pipeline_start() may fail
...
Merge tag 'mmc-fixes-for-3.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc
Pull MMC fixes from Chris Ball:
- Revert a patch that made failing to select power class fatal;
it turns out that it fails non-fatally on Tegra boards.
Regression against 3.5-rc1.
- Add the IRQF_ONESHOT flag to the cd-gpio driver, which turned
into a regression in 3.5-rc1 when IRQF_ONESHOT became required
for threaded IRQs with no handler.
* tag 'mmc-fixes-for-3.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
mmc: cd-gpio: pass IRQF_ONESHOT to request_threaded_irq()
mmc: core: Revert "skip card initialization if power class selection fails"
Merge tag 'for-linus-20120712' of git://git.infradead.org/linux-mtd
Pull late MTD fixes from David Woodhouse:
- fix 'sparse warning fix' regression which totally breaks MXC NAND
- fix GPMI NAND regression when used with UBI
- update/correct sysfs documentation for new 'bitflip_threshold' field
- fix nandsim build failure
* tag 'for-linus-20120712' of git://git.infradead.org/linux-mtd:
mtd: nandsim: don't open code a do_div helper
mtd: ABI documentation: clarification of bitflip_threshold
mtd: gpmi-nand: fix read page when reading to vmalloced area
mtd: mxc_nand: use 32bit copy functions