Commit Graph

2398 Commits

Author SHA1 Message Date
Artem Bityutskiy
07be303d22 mtd: mtdram: initialize writebufsize field
Set the 'mtd->writebufsize' field to 64 to mimic modern CFI flashes.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:42 +00:00
Gabor Juhos
37a23c2018 mtd: m25p80: add support for the EON EN25F32 chip
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:42 +00:00
Holger Brunck
771df61949 mtd: adapt writebufsize calculation for concat
If different chips with different writebufsize are concatenated,
the writebufsize from the concat device has to be taken from
the device with the largest writebuffer. This writebufsize
is used later on in the UBI layer for the min I/O size.

Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:42 +00:00
Hong Xu
cbc6c5e73d mtd: atmel_nand: Add DMA support to access Nandflash
Some SAM9 chips have the ability to perform DMA between CPU and SMC controller.
This patch adds DMA support for SAM9RL, SAM9G45, SSAM9G46,AM9M10, SAM9M11.

Signed-off-by: Hong Xu <hong.xu@atmel.com>
Tested-by: Ryan Mallon <ryan@bluewatersys.com>
Acked-by: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:42 +00:00
H Hartley Sweeten
7f53f12f02 mtd: mtd_blkdevs: local symbols should be static
The function blktrans_dev_release and blktrans_dev_put are only used
locally in this file and should be static.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:42 +00:00
H Hartley Sweeten
ca91facf6b mtd: local symbols should be static
The three backing_dev_info symbols are only used in this file and
should be static.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:41 +00:00
Jamie Iles
83025c824f mtd: mpc5121_nfc: don't treat NULL clk as an error
clk_get() returns a struct clk cookie to the driver and some platforms
may return NULL if they only support a single clock.  clk_get() has only
failed if it returns a ERR_PTR() encoded pointer.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:41 +00:00
Dmitry Eremin-Solenikov
f53fdebcc3 mtd: drop MTD_CONCAT from Kconfig entirely
As there are no more dependencies on MTD_CONCAT or CONFIG_MTD_CONCAT,
drop this entry from Kconfig entirely.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:41 +00:00
Dmitry Eremin-Solenikov
a8adc3f01b mtd: drop CONFIG_MTD_CONCAT ifdefs
As MTD_CONCAT is becoming a part of mtd core, it's now meaningless
to to check for it in ifdefs. Drop such references from MTD code.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:40 +00:00
Dmitry Eremin-Solenikov
e1d6ee7222 mtd: drop MTD_CONCAT dependencies from Kconfig
As MTD_CONCAT is becoming a part of mtd core, it's no longer necessary
to depend on it in Kconfig scripts. Drop such references.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:40 +00:00
Dmitry Eremin-Solenikov
4d42942cff mtd: make MTD_CONCAT support mandatory
Move mtdconcat to be an integral part of the mtd core. It's a tiny bit
of code, which bears 'say Y if you don't know what to do' note in the
Kconfig. OTOH there are several ugly ifdefs depending on the MTD_CONCAT.
So, making MTD_CONCAT support mandatory will allow us to clean up code a
lot.

Kconfig entry is changed to be a bool defaulting to Y, so all code
pieces depending on it, will have MTD_CONCAT Kconfig symbol and
CONFIG_MTD_CONCAT define. This will be removed in one of next patches.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-11 14:22:40 +00:00
Axel Lin
c804c73384 mtd: add "platform:" prefix for platform modalias
Since 43cc71eed1 (platform: prefix MODALIAS
with "platform:"), the platform modalias is prefixed with "platform:".

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
2011-03-11 14:20:05 +00:00
Maxim Levitsky
bd637f6f22 mtd: mtd_blkdevs: fix double free on error path
This one liner patch fixes double free that will occur if add_mtd_blktrans_dev
fails. On failure it frees the input argument, but all its users also free it
on error which is natural thing to do. Thus don't free it.

All credit for finding that bug belongs to reporters of the bug in the android bugzilla
http://code.google.com/p/android/issues/detail?id=13761

Commit message tweaked by Artem.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
2011-03-11 14:19:44 +00:00
Stanislaw Gruszka
82013d988f mtd: amd76xrom: fix oops at boot when resources are not available
For some unknown reasons resources needed by amd76xrom driver can be
unavailable. And instead of returning an error, the driver keeps going
and crash the kernel. This patch fixes the problem by making the driver
return -EBUSY if the resources are not available.

Commit messages tweaked by Artem.

Reported-by: Russell Whitaker <russ@ashlandhome.net>
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
2011-03-11 14:19:09 +00:00
Joakim Tjernlund
ecf3fde07c mtd: fix race in cfi_cmdset_0001 driver
As inval_cache_and_wait_for_operation() drop and reclaim the lock
to invalidate the cache, some other thread may suspend the operation
before reaching the for(;;) loop. Therefore the loop must start with
checking the chip->state before reading status from the chip.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Acked-by: Michael Cashwell <mboards@prograde.net>
Acked-by: Stefan Bigler <stefan.bigler@keymile.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org
2011-03-11 12:09:07 +00:00
Antony Pavlov
ceabebb2bd mtd: jedec_probe: initialise make sector erase command variable
In the commit 08968041be
 (mtd: cfi_cmdset_0002: make sector erase command variable)
introdused a field sector_erase_cmd. In the same commit initialisation
of cfi->sector_erase_cmd made in cfi_chip_setup()
(file drivers/mtd/chips/cfi_probe.c), so the CFI chip has no problem:

...
        cfi->cfi_mode = CFI_MODE_CFI;
        cfi->sector_erase_cmd = CMD(0x30);
...

But for the JEDEC chips this initialisation is not carried out,
so the JEDEC chips have sector_erase_cmd == 0.

This patch adds the missing initialisation.

Signed-off-by: Antony Pavlov <antony@niisi.msk.ru>
Acked-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
CC: stable@kernel.org
2011-03-11 12:05:54 +00:00
Antony Pavlov
efba2e313e mtd: jedec_probe: Change variable name from cfi_p to cfi
In the following commit, we'll need to use the CMD() macro in order to
fix the initialisation of the sector_erase_cmd field. That requires the
local variable to be called 'cfi', so change it first in a simple patch.

Signed-off-by: Antony Pavlov <antony@niisi.msk.ru>
Acked-by: Guillaume LECERF <glecerf@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
CC: stable@kernel.org
2011-03-11 12:05:24 +00:00
Linus Torvalds
ab2020f2f1 Merge git://git.infradead.org/mtd-2.6
* git://git.infradead.org/mtd-2.6: (59 commits)
  mtd: mtdpart: disallow reading OOB past the end of the partition
  mtd: pxa3xx_nand: NULL dereference in pxa3xx_nand_probe
  UBI: use mtd->writebufsize to set minimal I/O unit size
  mtd: initialize writebufsize in the MTD object of a partition
  mtd: onenand: add mtd->writebufsize initialization
  mtd: nand: add mtd->writebufsize initialization
  mtd: cfi: add writebufsize initialization
  mtd: add writebufsize field to mtd_info struct
  mtd: OneNAND: OMAP2/3: prevent regulator sleeping while OneNAND is in use
  mtd: OneNAND: add enable / disable methods to onenand_chip
  mtd: m25p80: Fix JEDEC ID for AT26DF321
  mtd: txx9ndfmc: limit transfer bytes to 512 (ECC provides 6 bytes max)
  mtd: cfi_cmdset_0002: add support for Samsung K8D3x16UxC NOR chips
  mtd: cfi_cmdset_0002: add support for Samsung K8D6x16UxM NOR chips
  mtd: nand: ams-delta: drop omap_read/write, use ioremap
  mtd: m25p80: add debugging trace in sst_write
  mtd: nand: ams-delta: select for built-in by default
  mtd: OneNAND: lighten scary initial bad block messages
  mtd: OneNAND: OMAP2/3: add support for command line partitioning
  mtd: nand: rearrange ONFI revision checking, add ONFI 2.3
  ...

Fix up trivial conflict in drivers/mtd/Kconfig as per DavidW.
2011-01-17 11:15:30 -08:00
Artem Bityutskiy
154bf89f5e mtd: mtdpart: disallow reading OOB past the end of the partition
This patch fixes the mtdpart bug which allows users reading OOB past the
end of the partition. This happens because 'part_read_oob()' allows reading
multiple OOB areas in one go, and mtdparts does not validate the OOB
length in the request.

Although there is such check in 'nand_do_read_oob()' in nand_base.c, but
it checks that we do not read past the flash chip, not the partition,
because in nand_base.c we work with the whole chip (e.g., mtd->size
in nand_base.c is the size of the whole chip). So this check cannot
be done correctly in nand_base.c and should be instead done in mtdparts.c.

This problem was reported by Jason Liu <r64343@freescale.com> and reproduced
with nandsim:

$ modprobe nandsim first_id_byte=0x20 second_id_byte=0xaa third_id_byte=0x00 \
                   fourth_id_byte=0x15 parts=0x400,0x400
$ modprobe nandsim mtd_oobtest.ko dev=0
$ dmesg
= snip =
mtd_oobtest: attempting to read past end of device
mtd_oobtest: an error is expected...
mtd_oobtest: error: read past end of device
= snip =
mtd_oobtest: finished with 2 errors

Reported-by: Jason Liu <liu.h.jason@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-17 15:25:48 +00:00
Al Viro
f03c65993b sanitize vfsmount refcounting changes
Instead of splitting refcount between (per-cpu) mnt_count
and (SMP-only) mnt_longrefs, make all references contribute
to mnt_count again and keep track of how many are longterm
ones.

Accounting rules for longterm count:
	* 1 for each fs_struct.root.mnt
	* 1 for each fs_struct.pwd.mnt
	* 1 for having non-NULL ->mnt_ns
	* decrement to 0 happens only under vfsmount lock exclusive

That allows nice common case for mntput() - since we can't drop the
final reference until after mnt_longterm has reached 0 due to the rules
above, mntput() can grab vfsmount lock shared and check mnt_longterm.
If it turns out to be non-zero (which is the common case), we know
that this is not the final mntput() and can just blindly decrement
percpu mnt_count.  Otherwise we grab vfsmount lock exclusive and
do usual decrement-and-check of percpu mnt_count.

For fs_struct.c we have mnt_make_longterm() and mnt_make_shortterm();
namespace.c uses the latter in places where we don't already hold
vfsmount lock exclusive and opencodes a few remaining spots where
we need to manipulate mnt_longterm.

Note that we mostly revert the code outside of fs/namespace.c back
to what we used to have; in particular, normal code doesn't need
to care about two kinds of references, etc.  And we get to keep
the optimization Nick's variant had bought us...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-16 13:47:07 -05:00
Linus Torvalds
275220f0fc Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
  block: ensure that completion error gets properly traced
  blktrace: add missing probe argument to block_bio_complete
  block cfq: don't use atomic_t for cfq_group
  block cfq: don't use atomic_t for cfq_queue
  block: trace event block fix unassigned field
  block: add internal hd part table references
  block: fix accounting bug on cross partition merges
  kref: add kref_test_and_get
  bio-integrity: mark kintegrityd_wq highpri and CPU intensive
  block: make kblockd_workqueue smarter
  Revert "sd: implement sd_check_events()"
  block: Clean up exit_io_context() source code.
  Fix compile warnings due to missing removal of a 'ret' variable
  fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
  block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
  cfq-iosched: don't check cfqg in choose_service_tree()
  fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
  cdrom: export cdrom_check_events()
  sd: implement sd_check_events()
  sr: implement sr_check_events()
  ...
2011-01-13 10:45:01 -08:00
Linus Torvalds
b2034d474b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (41 commits)
  fs: add documentation on fallocate hole punching
  Gfs2: fail if we try to use hole punch
  Btrfs: fail if we try to use hole punch
  Ext4: fail if we try to use hole punch
  Ocfs2: handle hole punching via fallocate properly
  XFS: handle hole punching via fallocate properly
  fs: add hole punching to fallocate
  vfs: pass struct file to do_truncate on O_TRUNC opens (try #2)
  fix signedness mess in rw_verify_area() on 64bit architectures
  fs: fix kernel-doc for dcache::prepend_path
  fs: fix kernel-doc for dcache::d_validate
  sanitize ecryptfs ->mount()
  switch afs
  move internal-only parts of ncpfs headers to fs/ncpfs
  switch ncpfs
  switch 9p
  pass default dentry_operations to mount_pseudo()
  switch hostfs
  switch affs
  switch configfs
  ...
2011-01-13 10:27:28 -08:00
Linus Torvalds
008d23e485 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
  Documentation/trace/events.txt: Remove obsolete sched_signal_send.
  writeback: fix global_dirty_limits comment runtime -> real-time
  ppc: fix comment typo singal -> signal
  drivers: fix comment typo diable -> disable.
  m68k: fix comment typo diable -> disable.
  wireless: comment typo fix diable -> disable.
  media: comment typo fix diable -> disable.
  remove doc for obsolete dynamic-printk kernel-parameter
  remove extraneous 'is' from Documentation/iostats.txt
  Fix spelling milisec -> ms in snd_ps3 module parameter description
  Fix spelling mistakes in comments
  Revert conflicting V4L changes
  i7core_edac: fix typos in comments
  mm/rmap.c: fix comment
  sound, ca0106: Fix assignment to 'channel'.
  hrtimer: fix a typo in comment
  init/Kconfig: fix typo
  anon_inodes: fix wrong function name in comment
  fix comment typos concerning "consistent"
  poll: fix a typo in comment
  ...

Fix up trivial conflicts in:
 - drivers/net/wireless/iwlwifi/iwl-core.c (moved to iwl-legacy.c)
 - fs/ext4/ext4.h

Also fix missed 'diabled' typo in drivers/net/bnx2x/bnx2x.h while at it.
2011-01-13 10:05:56 -08:00
Seiji Aguchi
fc2d557c74 kmsg_dump: constrain mtdoops and ramoops to perform their actions only for KMSG_DUMP_PANIC
This series aims to develop logging facility for enterprise use.

It is important to save kernel messages reliably on enterprise system
because they are helpful for diagnosing system.

This series add kmsg_dump() to the paths loosing kernel messages.  The use
case is the following.

[Use case of reboot/poweroff/halt/emergency_restart]

 My company has often experienced the followings in our support service.
 - Customer's system suddenly reboots.
 - Customers ask us to investigate the reason of the reboot.

We recognize the fact itself because boot messages remain in
/var/log/messages.  However, we can't investigate the reason why the
system rebooted, because the last messages don't remain.  And off course
we can't explain the reason.

We can solve above problem with this patch as follows.

 Case1: reboot with command
   - We can see "Restarting system with command:" or ""Restarting system.".

 Case2: halt with command
   - We can see "System halted.".

 Case3: poweroff with command
   - We can see " Power down.".

 Case4: emergency_restart with sysrq.
   - We can see "Sysrq:" outputted in __handle_sysrq().

 Case5: emergency_restart with softdog.
   - We can see "Initiating system reboot" in watchdog_fire().

So, we can distinguish the reason of reboot, poweroff, halt and emergency_restart.

If customer executed reboot command, you may think the customer should
know the fact.  However, they often claim they don't execute the command
when they rebooted system by mistake.

No message remains on the current Linux kernel, so we can't show the proof
to the customer.  This patch improves this situation.

This patch:

Alters mtdoops and ramoops to perform their actions only for
KMSG_DUMP_PANIC, KMSG_DUMP_OOPS and KMSG_DUMP_KEXEC because they would
like to log crashes only.

Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Marco Stornelli <marco.stornelli@gmail.com>
Reviewed-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:07 -08:00
Al Viro
c74a1cbb3c pass default dentry_operations to mount_pseudo()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-12 20:03:43 -05:00
Linus Torvalds
0bd2cbcdfa Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6
* 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6: (29 commits)
  of/flattree: forward declare struct device_node in of_fdt.h
  ipmi: explicitly include of_address.h and of_irq.h
  sparc: explicitly cast negative phandle checks to s32
  powerpc/405: Fix missing #{address,size}-cells in i2c node
  powerpc/5200: dts: refactor dts files
  powerpc/5200: dts: Change combatible strings on localbus
  powerpc/5200: dts: remove unused properties
  powerpc/5200: dts: rename nodes to prepare for refactoring dts files
  of/flattree: Update dtc to current mainline.
  of/device: Don't register disabled devices
  powerpc/dts: fix syntax bugs in bluestone.dts
  of: Fixes for OF probing on little endian systems
  of: make drivers depend on CONFIG_OF instead of CONFIG_PPC_OF
  of/flattree: Add of_flat_dt_match() helper function
  of_serial: explicitly include of_irq.h
  of/flattree: Refactor unflatten_device_tree and add fdt_unflatten_tree
  of/flattree: Reorder unflatten_dt_node
  of/flattree: Refactor unflatten_dt_node
  of/flattree: Add non-boottime device tree functions
  of/flattree: Add Kconfig for EARLY_FLATTREE
  ...

Fix up trivial conflict in arch/sparc/prom/tree_32.c as per Grant.
2011-01-10 08:57:03 -08:00
Linus Torvalds
b4a45f5fe8 Merge branch 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin
* 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin: (57 commits)
  fs: scale mntget/mntput
  fs: rename vfsmount counter helpers
  fs: implement faster dentry memcmp
  fs: prefetch inode data in dcache lookup
  fs: improve scalability of pseudo filesystems
  fs: dcache per-inode inode alias locking
  fs: dcache per-bucket dcache hash locking
  bit_spinlock: add required includes
  kernel: add bl_list
  xfs: provide simple rcu-walk ACL implementation
  btrfs: provide simple rcu-walk ACL implementation
  ext2,3,4: provide simple rcu-walk ACL implementation
  fs: provide simple rcu-walk generic_check_acl implementation
  fs: provide rcu-walk aware permission i_ops
  fs: rcu-walk aware d_revalidate method
  fs: cache optimise dentry and inode for rcu-walk
  fs: dcache reduce branches in lookup path
  fs: dcache remove d_mounted
  fs: fs_struct use seqlock
  fs: rcu-walk for path lookup
  ...
2011-01-07 08:56:33 -08:00
Nick Piggin
b3e19d924b fs: scale mntget/mntput
The problem that this patch aims to fix is vfsmount refcounting scalability.
We need to take a reference on the vfsmount for every successful path lookup,
which often go to the same mount point.

The fundamental difficulty is that a "simple" reference count can never be made
scalable, because any time a reference is dropped, we must check whether that
was the last reference. To do that requires communication with all other CPUs
that may have taken a reference count.

We can make refcounts more scalable in a couple of ways, involving keeping
distributed counters, and checking for the global-zero condition less
frequently.

- check the global sum once every interval (this will delay zero detection
  for some interval, so it's probably a showstopper for vfsmounts).

- keep a local count and only taking the global sum when local reaches 0 (this
  is difficult for vfsmounts, because we can't hold preempt off for the life of
  a reference, so a counter would need to be per-thread or tied strongly to a
  particular CPU which requires more locking).

- keep a local difference of increments and decrements, which allows us to sum
  the total difference and hence find the refcount when summing all CPUs. Then,
  keep a single integer "long" refcount for slow and long lasting references,
  and only take the global sum of local counters when the long refcount is 0.

This last scheme is what I implemented here. Attached mounts and process root
and working directory references are "long" references, and everything else is
a short reference.

This allows scalable vfsmount references during path walking over mounted
subtrees and unattached (lazy umounted) mounts with processes still running
in them.

This results in one fewer atomic op in the fastpath: mntget is now just a
per-CPU inc, rather than an atomic inc; and mntput just requires a spinlock
and non-atomic decrement in the common case. However code is otherwise bigger
and heavier, so single threaded performance is basically a wash.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:33 +11:00
Dan Carpenter
52d039fdaa mtd: pxa3xx_nand: NULL dereference in pxa3xx_nand_probe
"info->cmdset" gets dereferenced in __readid() so it needs to be
initialized earlier in the function.  This bug was introduced in
18c81b1828 "mtd: pxa3xx_nand: remove the flash info in driver
structure".

Cc: stable@kernel.org [2.6.37+]
Reported-and-tested-by: Sven Neumann <s.neumann@raumfeld.com>
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:48:59 +00:00
Anatolij Gustschin
a121f64399 UBI: use mtd->writebufsize to set minimal I/O unit size
Previously we used mtd->writesize field to set UBI's minimal
I/O unit size. This sometimes caused UBIFS recovery issues
when mounting an uncleanly unmounted UBIFS partition on NOR
flash since mtd->writesize is 1 byte for NOR flash. The
MTD CFI driver however often performs writing multiple
bytes in one programming operation using the chip's write
buffer. We have to use the size of this write buffer as
a minimal I/O unit size for UBI on NOR flash to fix the
observed UBIFS recovery issues.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:36:00 +00:00
Anatolij Gustschin
7fa33ac0a7 mtd: initialize writebufsize in the MTD object of a partition
Propagate the writebufsize to the partition's MTD object so
that UBI can set correct value for it's minimal I/O size
using the writebufsize field of MTD object of the partition.

By previous patches we added proper writebufsize field
initialization. Next patch can now change UBI to use
this field for setting the minimal I/O size.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:35:58 +00:00
Anatolij Gustschin
25dcd29786 mtd: onenand: add mtd->writebufsize initialization
Initialize mtd->writebufsize to be equal to mtd->writesize.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:35:57 +00:00
Anatolij Gustschin
cbcab65a17 mtd: nand: add mtd->writebufsize initialization
Initialize mtd->writebufsize to be equal to mtd->writesize.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:35:55 +00:00
Anatolij Gustschin
d261c72ae0 mtd: cfi: add writebufsize initialization
Initialize mtd->writebufsize to the value obtained
by CFI query command at probe time.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:35:53 +00:00
Adrian Hunter
9ac4e613a8 mtd: OneNAND: OMAP2/3: prevent regulator sleeping while OneNAND is in use
Prevent OneNAND's voltage regulator from going to sleep while
OneNAND is in use, by explicitly enabling and disabling the
regulator as appropriate.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:34:34 +00:00
Adrian Hunter
cf24dc85ff mtd: OneNAND: add enable / disable methods to onenand_chip
Add enable / disable methods called from get_device() / release_device().
These can be used, for example, to allow the driver to prevent the voltage
regulator from being put to sleep while OneNAND is in use.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:34:19 +00:00
Aleksandr Koltsoff
8fffed8cfd mtd: m25p80: Fix JEDEC ID for AT26DF321
The last byte of the ID should be zero for this chip. Was added in
commit d0e8c47c58 . Reported by Tomi
Varjo.

Signed-off-by: Aleksandr Koltsoff <aleksandr.koltsoff@ebts.fi>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:34:02 +00:00
Ralf Rösch
24ac9a94f9 mtd: txx9ndfmc: limit transfer bytes to 512 (ECC provides 6 bytes max)
See commit: c0cbfd0e81
Using __nand_correct_data() helper function, this driver can read 512
byte (with 6 byte ECC) at a time.

This is correct, but not more:
With NAND chips providing page sizes > 512 Bytes
chip->ecc.bytes are calculated > 6 in txx9ndfmc_nand_scan.
According the data sheet there are (only) 6 bytes ECC available.

After applying the patch a Hynix 512M*8 with 2KiB page size could be
successfully formatted and used with an ubifs file system.

Signed-off-by: Ralf Roesch <ralf.roesch@rw-gmbh.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:29:12 +00:00
Guillaume LECERF
e8953b7395 mtd: cfi_cmdset_0002: add support for Samsung K8D3x16UxC NOR chips
These chips report CFI v3.3 [1], so patch them on the fly to the more
correct v1.3.
Discussed and tested by the OpenWRT people [2].

[1] http://www.samsung.com/global/system/business/semiconductor/product/2007/6/11/NORFlash/32Mbit/K8D3216UBC/ds_K8D3x16UxC_rev17.pdf
[2] https://dev.openwrt.org/ticket/866

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:28:53 +00:00
Guillaume LECERF
e637276370 mtd: cfi_cmdset_0002: add support for Samsung K8D6x16UxM NOR chips
These chips report CFI v0.0 [1], so extend cfi_fixup_major_minor()
to patch all Samsung chips from 0.0 to 1.0.
Discussed and tested by the OpenWRT people [2].

[1] http://www.samsung.com/global/system/business/semiconductor/product/2007/6/11/NORFlash/64Mbit/K8D6316UTM/ds_K8D6x16UxM_rev16.pdf
[2] https://dev.openwrt.org/ticket/7348

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:28:51 +00:00
Janusz Krzysztofik
eaca491f75 mtd: nand: ams-delta: drop omap_read/write, use ioremap
There is a common requirement for not using OMAP specific omap_readw() /
omap_writew() function calls in drivers/, but replace them with
readw() / writew() on ioremap()ped addresses passed from arch/ instead.

The patch implements this idea for the Amstrad Delta NAND driver. To be
able to use the modified driver, the board file is updated with the
platform device I/O resource declaration, which is passed from there.

Created and tested against linux-2.6.37-rc5, on top of recent patch
'MTD: NAND: ams-delta: convert to platform driver'.

Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:28:22 +00:00
Nicolas Ferre
dcf12463c3 mtd: m25p80: add debugging trace in sst_write
Add a DEBUG(MTD_DEBUG_LEVEL2, ..) trace at beginning of sst_write() function as
it is done in m25p80_write() function.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:28:06 +00:00
Janusz Krzysztofik
494f45d55b mtd: nand: ams-delta: select for built-in by default
Now that the Amstrad Delta NAND driver is converted to a platform driver,
which prevents it from interfering with other unrelated hardware in multiple
OMAP1 cpu and machine configurations, it can be automatically configured for
being built into the kernel if the Amstrad Delta board is also selected.

Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:27:09 +00:00
Adrian Hunter
e0c1a921f6 mtd: OneNAND: lighten scary initial bad block messages
Initial bad blocks are normal but the messages look like
errors.  Make the messages less scary, make the main
message an informational message not a warning, make the
message displaying registers a debug message and include
the address there instead of in the informational message.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:23:10 +00:00
Adrian Hunter
263a8c8635 mtd: OneNAND: OMAP2/3: add support for command line partitioning
Add the ability to parse MTD partition information from the
kernel command line.

Note that a pointless BUG_ON is removed, as are redundant
calls to 'del_mtd_partitions()' and 'del_mtd_device()'
because they are also done by 'onenand_release()'.

Finally note that 'add_mtd_device()' returns 1 on failure
so the error condition was incorrect.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:22:45 +00:00
Brian Norris
b7b1a29d94 mtd: nand: rearrange ONFI revision checking, add ONFI 2.3
In checking for the ONFI revision, the first conditional (for checking
"unsupported" ONFI) seems unnecessary.  All ONFI revisions should be
backwards-compatible; even if this is not the case on some newer ONFI
revision, it should simply fail the second version-checking if-else block
(i.e., the bit-fields for 1.0, 2.0, etc. would not be set to 1). Thus, we
move our "unsupported" condition after having checked each bit field.

Also, it's simple enough to add a condition for ONFI revision 2.3. Note
that this does *NOT* mean we handle all new features of ONFI versions
above 1.0.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Florian Fainelli <ffainelli@freebox.fr>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:19:20 +00:00
Brian Norris
0b524fb931 mtd: nand: choose correct chip name (ONFI bug)
We have the order of the conditional wrong for choosing the ONFI chip name
vs. the ID table name. Without this fix, we will almost *always* choose a
NULL string to print out instead of the correct one.

This has already been suggested by Matthieu Castet.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Florian Fainelli <ffainelli@freebox.fr>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:18:45 +00:00
Janusz Krzysztofik
7e95d1f171 mtd: nand: ams-delta: convert to platform driver
In its current form, the driver may interfere with different hardware on
different boards if built into the kernel, hence is not suitable for
inclusion into a defconfig, inteded to be usable with multiple OMAP1 cpu and
machine types.

Convert it to a platform driver, that should be free from this issue.

Created and tested against linux-2.6.37-rc5 on Amstrad Delta.

Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:18:16 +00:00
Tejun Heo
75c52a4963 mtd: don't use flush_scheduled_work()
flush_scheduled_work() is deprecated and scheduled to be removed.
Directly flush cxt->work_{erase|write} on removal instead.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:17:08 +00:00
Kyungmin Park
d983c54ebd mtd: OneNAND: Fix multi block erase support at 4KiB pagesize
Original 4KiB pagesize chip (SLC) doesn't support Multi block erase at Spec.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-01-06 15:16:39 +00:00