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>
Function mtd_has_master renamed as mtd_is_partition to follow the function logic.
The patch fixes the problem of checking the right mtd device for partition creation.
To delete partition checking is not needed here so as it is done in mtd_del_partition.
By master we consider the mtd device which does not belong to any partition.
Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Structure mtd_info_user is copied to userland with padding byted
between "type" and "flags" fields uninitialized. It leads to leaking
of contents of kernel stack memory.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* git://git.infradead.org/mtd-2.6: (82 commits)
mtd: fix build error in m25p80.c
mtd: Remove redundant mutex from mtd_blkdevs.c
MTD: Fix wrong check register_blkdev return value
Revert "mtd: cleanup Kconfig dependencies"
mtd: cfi_cmdset_0002: make sector erase command variable
mtd: cfi_cmdset_0002: add CFI detection for SST 38VF640x chips
mtd: cfi_util: add support for switching SST 39VF640xB chips into QRY mode
mtd: cfi_cmdset_0001: use defined value of P_ID_INTEL_PERFORMANCE instead of hardcoded one
block2mtd: dubious assignment
P4080/mtd: Fix the freescale lbc issue with 36bit mode
P4080/eLBC: Make Freescale elbc interrupt common to elbc devices
mtd: phram: use KBUILD_MODNAME
mtd: OneNAND: S5PC110: Fix double call suspend & resume function
mtd: nand: fix MTD_MODE_RAW writes
jffs2: use kmemdup
mtd: sm_ftl: cosmetic, use bool when possible
mtd: r852: remove useless pci powerup/down from suspend/resume routines
mtd: blktrans: fix a race vs kthread_stop
mtd: blktrans: kill BKL
mtd: allow to unload the mtdtrans module if its block devices aren't open
...
Fix up trivial whitespace-introduced conflict in drivers/mtd/mtdchar.c
Conflicts:
drivers/mtd/mtd_blkdevs.c
Merge Grant's device-tree bits so that we can apply the subsequent fixes.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Add support for mtd repartition based on the block
device BLKPG interface:
BLKPG_ADD_PARTITION - for partition creation;
BLKPG_DEL_PARTITION - for partition delete
The usage is based on BLKPG ioctl called with
struct blkpg_ioctl_arg argument which includes the
reference to struct blkpg_partition discribing the
partition offset and length.
Disadvantage: there is no implementation for mtd
flags control. The flags are always borrowed from
the master device.
Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
If "ur_idx" is wrong we could go past the end of the array. The
"ur_idx" comes from root so it's not a huge deal, but adding a sanity
check makes the code more robust.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
There were some improvements and additions necessary in the
comments explaining of the expansion of nand_ecclayout, the
introduction of nand_ecclayout_user, and the deprecation of the
ioctl ECCGETLAYOUT.
Also, I found a better placement for the macro MTD_MAX_ECCPOS_ENTRIES;
next to the definition of MTD_MAX_OOBFREE_ENTRIES in mtd-abi.h. The macro
is really only important for the ioctl code (found in drivers/mtd/mtdchar.c)
but since there are small edits being made to the user-space header, I
figured this is a better location.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
struct nand_ecclayout is too small for many new chips; OOB regions can be as
large as 448 bytes and may increase more in the future. Thus, copying that
struct to user-space with the ECCGETLAYOUT ioctl is not a good idea; the ioctl
would have to be updated every time there's a change to the current largest
size.
Instead, the old nand_ecclayout is renamed to nand_ecclayout_user and a
new struct nand_ecclayout is created that can accomodate larger sizes and
expand without affecting the user-space. struct nand_ecclayout can still
be used in board drivers without modification -- at least for now.
A new function is provided to convert from the new to the old in order to
allow the deprecated ioctl to continue to work with truncated data. Perhaps
the ioctl, the conversion process, and the struct nand_ecclayout_user can be
removed altogether in the future.
Note: There are comments in nand/davinci_nand.c::nand_davinci_probe()
regarding this issue; this driver (and maybe others) can be updated to
account for extra space. All kernel drivers can use the expanded
nand_ecclayout as a drop-in replacement and ignore its benefits.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
All these files use the big kernel lock in a trivial
way to serialize their private file operations,
typically resulting from an earlier semi-automatic
pushdown from VFS.
None of these drivers appears to want to lock against
other code, and they all use the BKL as the top-level
lock in their file operations, meaning that there
is no lock-order inversion problem.
Consequently, we can remove the BKL completely,
replacing it with a per-file mutex in every case.
Using a scripted approach means we can avoid
typos.
file=$1
name=$2
if grep -q lock_kernel ${file} ; then
if grep -q 'include.*linux.mutex.h' ${file} ; then
sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
else
sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
fi
sed -i ${file} \
-e "/^#include.*linux.mutex.h/,$ {
1,/^\(static\|int\|long\)/ {
/^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);
} }" \
-e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
-e '/[ ]*cycle_kernel_lock();/d'
else
sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \
-e '/cycle_kernel_lock()/d'
fi
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: David Woodhouse <David.Woodhouse@intel.com>
Cc: linux-mtd@lists.infradead.org
* git://git.infradead.org/mtd-2.6: (79 commits)
mtd: Remove obsolete <mtd/compatmac.h> include
mtd: Update copyright notices
jffs2: Update copyright notices
mtd-physmap: add support users can assign the probe type in board files
mtd: remove redwood map driver
mxc_nand: Add v3 (i.MX51) Support
mxc_nand: support 8bit ecc
mxc_nand: fix correct_data function
mxc_nand: add V1_V2 namespace to registers
mxc_nand: factor out a check_int function
mxc_nand: make some internally used functions overwriteable
mxc_nand: rework get_dev_status
mxc_nand: remove 0xe00 offset from registers
mtd: denali: Add multi connected NAND support
mtd: denali: Remove set_ecc_config function
mtd: denali: Remove unuseful code in get_xx_nand_para functions
mtd: denali: Remove device_info_tag structure
mtd: m25p80: add support for the Winbond W25Q32 SPI flash chip
mtd: m25p80: add support for the Intel/Numonyx {16,32,64}0S33B SPI flash chips
mtd: m25p80: add support for the EON EN25P{32, 64} SPI flash chips
...
Fix up trivial conflicts in drivers/mtd/maps/{Kconfig,redwood.c} due to
redwood driver removal.
For no-mmu systems mmap() on RAM/ROM devices already works
but for systems with mmu it probably was not tested and
doesn't work.
This patch allows using mmap() on MTD RAM/ROM devices on systems
with MMU. It has been tested on mpc5121e based platform with
MR0A16A MRAM device attached over LocalBus.
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This patchs adds a way for user space programs to find out whether a
flash sector is locked. An optional driver method in the mtd_info struct
provides the information.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* git://git.infradead.org/~dwmw2/mtd-2.6.35:
jffs2: update ctime when changing the file's permission by setfacl
jffs2: Fix NFS race by using insert_inode_locked()
jffs2: Fix in-core inode leaks on error paths
mtd: Fix NAND submenu
mtd/r852: update card detect early.
mtd/r852: Fixes in case of DMA timeout
mtd/r852: register IRQ as last step
drivers/mtd: Use memdup_user
docbook: make mtd nand module init static
* 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing:
uml: Pushdown the bkl from harddog_kern ioctl
sunrpc: Pushdown the bkl from sunrpc cache ioctl
sunrpc: Pushdown the bkl from ioctl
autofs4: Pushdown the bkl from ioctl
uml: Convert to unlocked_ioctls to remove implicit BKL
ncpfs: BKL ioctl pushdown
coda: Clean-up whitespace problems in pioctl.c
coda: BKL ioctl pushdown
drivers: Push down BKL into various drivers
isdn: Push down BKL into ioctl functions
scsi: Push down BKL into ioctl functions
dvb: Push down BKL into ioctl functions
smbfs: Push down BKL into ioctl function
coda/psdev: Remove BKL from ioctl function
um/mmapper: Remove BKL usage
sn_hwperf: Kill BKL usage
hfsplus: Push down BKL into ioctl function
Use memdup_user when user data is immediately copied into the
allocated region.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression from,to,size,flag;
position p;
identifier l1,l2;
@@
- to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+ to = memdup_user(from,size);
if (
- to==NULL
+ IS_ERR(to)
|| ...) {
<+... when != goto l1;
- -ENOMEM
+ PTR_ERR(to)
...+>
}
- if (copy_from_user(to, from, size) != 0) {
- <+... when != goto l2;
- -EFAULT
- ...+>
- }
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
We cannot modify file->f_mapping->backing_dev_info, because it will corrupt
backing device of device node inode, since file->f_mapping is equal to
inode->i_mapping (see __dentry_open() in fs/open.c).
Let's introduce separate inode for MTD device with appropriate backing
device.
[dwmw2: Refactor to keep it all entirely within mtdchar.c; use iget_locked()]
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
These are the last remaining device drivers using
the ->ioctl file operation in the drivers directory
(except from v4l drivers).
[fweisbec: drop i8k pushdown as it has been done from
procfs pushdown branch already]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
register_chrdev() registers minor numbers up to 255, but we can now
potentially have much larger numbers.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
MAX_MTD_DEVICES is about to be removed.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
In mtd_ioctl MEMGETREGIONINFO the region_user_info pointer ur
is cast in __kernel space. This produces a number of sparse warnings
like:
warning: cast removes address space of expression
warning: incorrect type in initializer (different address spaces)
expected unsigned int const [noderef] <asn:1>*register __p
got unsigned int *<noident>
Since argp is already a void __user * just use it dirrectly without
the cast and make ur a __user *.
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>
Remove all references to MTD ioctls from fs/compat_ioctl.c and let
them all be handled by mtd_compat_ioctl().
Signed-off-by: Kevin Cernekee <kpc.mtd@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
1) Move the MEMREADOOB/MEMWRITEOOB compat_ioctl wrappers from
fs/compat_ioctl.c into mtdchar.c . Original request was here:
http://lkml.org/lkml/2009/4/1/295
2) Add missing COMPATIBLE_IOCTL lines, so that mtd-utils does not error
out when running in 64/32 compatibility mode.
LKML-Reference: <200904011650.22928.arnd@arndb.de>
Signed-off-by: Kevin Cernekee <kpc.mtd@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
New MEMERASE/MEMREADOOB/MEMWRITEOOB ioctls are needed in order to support
64-bit offsets into large NAND flash devices.
Signed-off-by: Kevin Cernekee <kpc.mtd@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Update driver model support in the MTD framework, so it fits
better into the current udev-based hotplug framework:
- Each mtd_info now has a device node. MTD drivers should set
the dev.parent field to point to the physical device, before
setting up partitions or otherwise declaring MTDs.
- Those device nodes always map to /sys/class/mtdX device nodes,
which no longer depend on MTD_CHARDEV.
- Those mtdX sysfs nodes have a "starter set" of attributes;
it's not yet sufficient to replace /proc/mtd.
- Enabling MTD_CHARDEV provides /sys/class/mtdXro/ nodes and the
/sys/class/mtd*/dev attributes (for udev, mdev, etc).
- Include a MODULE_ALIAS_CHARDEV_MAJOR macro. It'll work with
udev creating the /dev/mtd* nodes, not just a static rootfs.
So the sysfs structure is pretty much what you'd expect, except
that readonly chardev nodes are a bit quirky.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Present backing device capabilities for MTD character device files to allow
NOMMU mmap to do direct mapping where possible.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
The mtdchar module is missing the char-major-90-* alias that would cause
it to be auto-loaded when a device of that type is opened. This patch
adds the alia..
Signed-off-by: Scott James Remnant <scott@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
MTD internal API presently uses 32-bit values to represent
device size. This patch updates them to 64-bits but leaves
the external API unchanged. Extending the external API
is a separate issue for several reasons. First, no one
needs it at the moment. Secondly, whether the implementation
is done with IOCTLs, sysfs or both is still debated. Thirdly
external API changes require the internal API to be accepted
first.
Note that although the MTD API will be able to support 64-bit
device sizes, existing drivers do not and are not required
to do so, although NAND base has been updated.
In general, changing from 32-bit to 64-bit values cause little
or no changes to the majority of the code with the following
exceptions:
- printk message formats
- division and modulus of 64-bit values
- NAND base support
- 32-bit local variables used by mtdpart and mtdconcat
- naughtily assuming one structure maps to another
in MEMERASE ioctl
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* git://git.infradead.org/mtd-2.6: (69 commits)
Revert "[MTD] m25p80.c code cleanup"
[MTD] [NAND] GPIO driver depends on ARM... for now.
[MTD] [NAND] sh_flctl: fix compile error
[MTD] [NOR] AT49BV6416 has swapped erase regions
[MTD] [NAND] GPIO NAND flash driver
[MTD] cmdlineparts documentation change - explain where mtd-id comes from
[MTD] cfi_cmdset_0002.c: Add Macronix CFI V1.0 TopBottom detection
[MTD] [NAND] Fix compilation warnings in drivers/mtd/nand/cs553x_nand.c
[JFFS2] Write buffer offset adjustment for NOR-ECC (Sibley) flash
[MTD] mtdoops: Fix a bug where block may not be erased
[MTD] mtdoops: Add a magic number to logged kernel oops
[MTD] mtdoops: Fix an off by one error
[JFFS2] Correct parameter names of jffs2_compress() in comments
[MTD] [NAND] sh_flctl: add support for Renesas SuperH FLCTL
[MTD] [NAND] Bug on atmel_nand HW ECC : OOB info not correctly written
[MTD] [MAPS] Remove unused variable after ROM API cleanup.
[MTD] m25p80.c extended jedec support (v2)
[MTD] remove unused mtd parameter in of_mtd_parse_partitions()
[MTD] [NAND] remove dead Kconfig associated with !CONFIG_PPC_MERGE
[MTD] [NAND] driver extension to support NAND on TQM85xx modules
...
The MEMGETREGIONINFO ioctl() in mtdchar.c was clobbering user memory by
overwriting more than intended, due the size of struct mtd_erase_region_info
changing in commit 0ecbc81adf ('Support
for auto locking flash on power up').
Fix avoids this by copying struct members one by one with put_user(), as there
is no longer a convenient struct to use the size of as the length argument to
copy_to_user().
Signed-off-by: Zev Weiss <zevweiss@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Now that we can tell when we have one of the newer DataFlash chips,
optionally expose the 128 bytes of OTP memory they provide. Tested
on at45db642 revision B and D chips.
Switch mtdchar over to a generic HAVE_MTD_OTP flag instead of adding
another #ifdef for each type of chip whose driver has OTP support.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Bryan Wu <cooloney@kernel.org>
Cc: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
device_create() is race-prone, so use the race-free
device_create_drvdata() instead as device_create() is going away.
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Use einfo, oinfo for the inner erase_info and otp_info structs used in
individual case statements.
drivers/mtd/mtdchar.c:582:26: warning: symbol 'info' shadows an earlier one
drivers/mtd/mtdchar.c:380:23: originally declared here
drivers/mtd/mtdchar.c:596:26: warning: symbol 'info' shadows an earlier one
drivers/mtd/mtdchar.c:380:23: originally declared here
drivers/mtd/mtdchar.c:704:19: warning: symbol 'info' shadows an earlier one
drivers/mtd/mtdchar.c:380:23: originally declared here
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
The copy_to_user was casting away the address space to get the offset of
the length member. Use offsetof() instead and add it to the void __user
*argp.
drivers/mtd/mtdchar.c:527:23: warning: cast removes address space of expression
drivers/mtd/mtdchar.c:527:23: warning: incorrect type in argument 1 (different address spaces)
drivers/mtd/mtdchar.c:527:23: expected void [noderef] <asn:1>*to
drivers/mtd/mtdchar.c:527:23: got unsigned int *<noident>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Once upon a time, the MTD repository was using CVS.
This patch therefore removes all usages of the no longer updated CVS
keywords from the MTD code.
This also includes code that printed them to the user.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
struct class_device is going away, this converts the code to use struct
device instead.
Signed-off-by: Tony Jones <tonyj@suse.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
"include/linux/mtd/mtd.h" declares "mtd_oob_ops.retlen" as size_t, which
is 64 bits on targets with a 64 bit addressing. The MEMWRITEOOB ioctl
calls copy_to_user() to write it back to "mtd_oob_buf.length", which is
declared in "include/linux/mtd-abi.h" as uint32_t. Since powerpc is a
big endian architecture, this only copies the upper 32 bits of the
address, which is always 0.
Signed-off-by: David Scidmore <dscidmore@xes-inc.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
sh:
drivers/mtd/mtdchar.c: In function `mtd_mmap':
drivers/mtd/mtdchar.c:817: error: dereferencing pointer to incomplete type
drivers/mtd/mtdchar.c:817: error: `VM_SHARED' undeclared (first use in this function)
drivers/mtd/mtdchar.c:817: error: (Each undeclared identifier is reported only once
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ops.len member is not initialized, because it is unused for this
operation. The length check needs to use ops.ooblen instead
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove unused and broken mtd->ecctype and mtd->eccsize fields
from struct mtd_info. Do not remove them from userspace API
data structures (don't want to breake userspace) but mark them
as obsolete by a comment. Any userspace program which uses them
should be half-broken anyway, so this is more about saving
data structure size.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
get_mtd_device() returns NULL in case of any failure. Teach it to return an
error code instead. Fix all users as well.
Signed-off-by: Artem Bityutskiy <dedekind@infradead.org>
As was discussed between Ricard Wanderlöf, David Woodhouse, Artem
Bityutskiy and me, the current API for reading/writing OOB is confusing.
The thing that introduces confusion is the need to specify ops.len
together with ops.ooblen for reads/writes that concern only OOB not data
area. So, ops.len is overloaded: when ops.datbuf != NULL it serves to
specify the length of the data read, and when ops.datbuf == NULL, it
serves to specify the full OOB read length.
The patch inlined below is the slightly updated version of the previous
patch serving the same purpose, but with the new Artem's comments taken
into account.
Artem, BTW, thanks a lot for your valuable input!
Signed-off-by: Vitaly Wool <vwool@ru.mvista.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
1. The ECCGETLAYOUT ioctl copy_to_user() call has a superfluous '&'
causing the resulting information to be garbage rather than the intended
mtd->ecclayout.
2. The MEMGETOOBSEL misses copying mtd->ecclayout->eccbytes so the
resulting field of the returned structure contains garbage.
Signed-off-by: Ricard Wanderlöf <ricardw@axis.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Allow lseek(mtdchar_fd, 0, SEEK_END) to succeed, which currently fails
with EINVAL.
lseek(fd, 0, SEEK_END) should result into the same fileposition as
lseek(fd, 0, SEEK_SET) + read(fd, buf, length(fd))
Furthermore, lseek(fd, 0, SEEK_CUR) should return the current file position,
which in case of an encountered EOF should not result in EINVAL
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Following problems are addressed:
- wrong status caused early break out of nand_wait()
- removed the bogus status check in nand_wait() which
is a relict of the abandoned support for interrupted
erase.
- status check moved to the correct place in read_oob
- oob support for syndrom based ecc with strange layouts
- use given offset in the AUTOOOB based oob operations
Partially based on a patch from Vitaly Vool <vwool@ru.mvista.com>
Thanks to Savin Zlobec <savin@epico.si> for tracking down the
status problem.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
mtdchar.c direcly copied part of struct mtd_info to userspace, thereby
implicitly making it part of the ABI. With this patch, struct
mtd_info is independent of the ABI and can have its fields removed,
reordered, etc.
Signed-off-by: Joern Engel <joern@wh.fh-wedel.de>
The raw read/write access to NAND (without ECC) has been changed in the
NAND rework. Expose the new way - setting the file mode via ioctl - to
userspace. Also allow to read out the ecc statistics information so userspace
tools can see that bitflips happened and whether errors where correctable
or not. Also expose the number of bad blocks for the partition, so nandwrite
can check if the data fits into the parition before writing to it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Return -EUCLEAN on read when a bitflip was detected and corrected, so the
clients can react and eventually copy the affected block to a spare one.
Make all in kernel users aware of the change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Hopefully the last iteration on this!
The handling of out of band data on NAND was accompanied by tons of fruitless
discussions and halfarsed patches to make it work for a particular
problem. Sufficiently annoyed by I all those "I know it better" mails and the
resonable amount of discarded "it solves my problem" patches, I finally decided
to go for the big rework. After removing the _ecc variants of mtd read/write
functions the solution to satisfy the various requirements was to refactor the
read/write _oob functions in mtd.
The major change is that read/write_oob now takes a pointer to an operation
descriptor structure "struct mtd_oob_ops".instead of having a function with at
least seven arguments.
read/write_oob which should probably renamed to a more descriptive name, can do
the following tasks:
- read/write out of band data
- read/write data content and out of band data
- read/write raw data content and out of band data (ecc disabled)
struct mtd_oob_ops has a mode field, which determines the oob handling mode.
Aside of the MTD_OOB_RAW mode, which is intended to be especially for
diagnostic purposes and some internal functions e.g. bad block table creation,
the other two modes are for mtd clients:
MTD_OOB_PLACE puts/gets the given oob data exactly to/from the place which is
described by the ooboffs and ooblen fields of the mtd_oob_ops strcuture. It's
up to the caller to make sure that the byte positions are not used by the ECC
placement algorithms.
MTD_OOB_AUTO puts/gets the given oob data automaticaly to/from the places in
the out of band area which are described by the oobfree tuples in the ecclayout
data structre which is associated to the devicee.
The decision whether data plus oob or oob only handling is done depends on the
setting of the datbuf member of the data structure. When datbuf == NULL then
the internal read/write_oob functions are selected, otherwise the read/write
data routines are invoked.
Tested on a few platforms with all variants. Please be aware of possible
regressions for your particular device / application scenario
Disclaimer: Any whining will be ignored from those who just contributed "hot
air blurb" and never sat down to tackle the underlying problem of the mess in
the NAND driver grown over time and the big chunk of work to fix up the
existing users. The problem was not the holiness of the existing MTD
interfaces. The problems was the lack of time to go for the big overhaul. It's
easy to add more mess to the existing one, but it takes alot of effort to go
for a real solution.
Improvements and bugfixes are welcome!
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Most of those macros are unused and the used ones just obfuscate
the code. Remove them and fixup all users.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The nand_oobinfo structure is not fitting the newer error correction
demands anymore. Replace it by struct nand_ecclayout and fixup the users
all over the place. Keep the nand_oobinfo based ioctl for user space
compability reasons.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The info structure for out of band data was copied into
the mtd structure. Make it a pointer and remove the ability
to set it from userspace. The position of ecc bytes is
defined by the hardware and should not be changed by software.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
One Block of the NAND Flash Array memory is reserved as
a One-Time Programmable Block memory area.
Also, 1st Block of NAND Flash Array can be used as OTP.
The OTP block can be read, programmed and locked using the same
operations as any other NAND Flash Array memory block.
OTP block cannot be erased.
OTP block is fully-guaranteed to be a valid block.
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
This patch removes repeated calls to kmalloc / kfree in mtd_write /
mtd_read functions, replacing them by a single kmalloc / kfree pair.
Signed-off-by: Thiago Galesi <thiagogalesi@gmail.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
I recently picked up my older work to remove unnecessary #includes of
sched.h, starting from a patch by Dave Jones to not include sched.h
from module.h. This reduces the number of indirect includes of sched.h
by ~300. Another ~400 pointless direct includes can be removed after
this disentangling (patch to follow later).
However, quite a few indirect includes need to be fixed up for this.
In order to feed the patches through -mm with as little disturbance as
possible, I've split out the fixes I accumulated up to now (complete for
i386 and x86_64, more archs to follow later) and post them before the real
patch. This way this large part of the patch is kept simple with only
adding #includes, and all hunks are independent of each other. So if any
hunk rejects or gets in the way of other patches, just drop it. My scripts
will pick it up again in the next round.
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The previous patch adding the ability to nest struct class_device
changed the paramaters to the call class_device_create(). This patch
fixes up all in-kernel users of the function.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
mtdchar return -EINVAL for seek prior to offset 0 or to beyond the last
byte in the device/partition, similar to various other seek methods,
instead of fixing up to first or last byte.
Signed-off-by: Todd Poynor <tpoynor@mvista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Switch from DEVFS to udev for dynamic creation of device nodes for mtd
char devices.
Creates a new LDM class "mtd" with writeable and read-only devices
registered for each mtdchar device.
From: Paolo Galtieri <pgaltieri@mvista.com>
Signed-off-by: Todd Poynor <tpoynor@mvista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This is implemented using a ioctl to switch the MTD char device into
one of the different OTP "modes", at which point read/write/seek can
operate on the selected OTP area. Also some extra ioctls to query
for size and lock protection segments or groups. Some example user
space utilities are provided.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Al Viro