Instead, call 'mtd_get_*_prot_info()' and check for '-EOPNOTSUPP'. While
on it, fix the return code from '-EOPNOTSUPP' to '-EINVAL' for the case
when the mode parameter is invalid.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Instead of checking whether 'mtd->read_oob' is defined, just call
'mtd_read_oob()' and handle the '-EOPNOTSUPP' error which will be returned
if the function is undefined.
Additionally, make 'mtd_write_oob()' return '-EOPNOTSUPP' if the function
is undefined.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Instead of checking if 'mtd->panic_write' is defined, call 'mtd_panic_write()'
and check the error code - '-EOPNOTSUPP' will be returned if the function is
not defined.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Remove direct usage of mtd->get_unmapped_area. Instead, just call
'mtd_get_unmapped_area()' which will return -EOPNOTSUPP if the function
is not implemented and test for this error code.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Remove direct usage of the "mtd->point" function pointer. Instead,
test the mtd_point() return code for '-EOPNOTSUPP'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
We are working in the direction of making sure that MTD clients to not
use 'mtd->func' pointers directly. In some places we want to know if
OOB operations are supported by an MTD device. Introduce 'mtd_has_oob()'
helper for these purposes.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
1. Teach 'mtd_write()' function to return '-EROFS' if the write method
is undefined, and remove the corresponding check from
'default_mtd_writev()'.
2. Do not test 'retlen' for NULL - it cannot be NULL.
3. Few minor coding stile clean-ups.
4. Add a kerneldoc comment
Additionally, minor fixes to the kerneldoc comments of the neighbor function.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Make sure that the retlen is set to 0 in case of error. This harmonizes
drivers - some set it to 0 in some error cases and do not write anything
in other error cases. Now we can do this consistently for all drivers.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Move the 'get_device()' and 'put_device()' functions up within
'struct mtd_info' to make them be close to other functions.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This patch is part of a patch-set which changes the MTD interface
from 'mtd->func()' form to 'mtd_func()' form. We need this because
we want to add common code to to all drivers in the mtd core level,
which is impossible with the current interface when MTD clients
call driver functions like 'read()' or 'write()' directly.
At this point we just introduce a new inline wrapper function, but
later some of them are expected to gain more code. E.g., the input
parameters check should be moved to the wrappers rather than be
duplicated at many drivers.
This particular patch introduced the 'mtd_erase()' interface. The
following patches add all the other interfaces one by one.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This patch fixes the following build failure:
In file included from include/linux/mtd/qinfo.h:4:0,
from include/linux/mtd/pfow.h:7,
from drivers/mtd/lpddr/lpddr_cmds.c:27:
include/linux/mtd/map.h: In function 'inline_map_read':
include/linux/mtd/map.h:409:3: error: implicit declaration of function 'BUILD_BUG_ON' [-Werror=implicit-function-declaration]
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This patch allows each CFI device map to use its own endianness. The
globally defined CFI endianness (CONFIG_MTD_CFI_NOSWAP,
CONFIG_MTD_CFI_BE_BYTE_SWAP or CONFIG_MTD_CFI_LE_BYTE_SWAP) becomes the
default value which can be overridden by a driver for a particular device.
Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Currently, the *_global_[un]lock_online() routines are not at all synchronized
with CPU hotplug. Soft-lockups detected as a consequence of this race was
reported earlier at https://lkml.org/lkml/2011/8/24/185. (Thanks to Cong Meng
for finding out that the root-cause of this issue is the race condition
between br_write_[un]lock() and CPU hotplug, which results in the lock states
getting messed up).
Fixing this race by just adding {get,put}_online_cpus() at appropriate places
in *_global_[un]lock_online() is not a good option, because, then suddenly
br_write_[un]lock() would become blocking, whereas they have been kept as
non-blocking all this time, and we would want to keep them that way.
So, overall, we want to ensure 3 things:
1. br_write_lock() and br_write_unlock() must remain as non-blocking.
2. The corresponding lock and unlock of the per-cpu spinlocks must not happen
for different sets of CPUs.
3. Either prevent any new CPU online operation in between this lock-unlock, or
ensure that the newly onlined CPU does not proceed with its corresponding
per-cpu spinlock unlocked.
To achieve all this:
(a) We introduce a new spinlock that is taken by the *_global_lock_online()
routine and released by the *_global_unlock_online() routine.
(b) We register a callback for CPU hotplug notifications, and this callback
takes the same spinlock as above.
(c) We maintain a bitmap which is close to the cpu_online_mask, and once it is
initialized in the lock_init() code, all future updates to it are done in
the callback, under the above spinlock.
(d) The above bitmap is used (instead of cpu_online_mask) while locking and
unlocking the per-cpu locks.
The callback takes the spinlock upon the CPU_UP_PREPARE event. So, if the
br_write_lock-unlock sequence is in progress, the callback keeps spinning,
thus preventing the CPU online operation till the lock-unlock sequence is
complete. This takes care of requirement (3).
The bitmap that we maintain remains unmodified throughout the lock-unlock
sequence, since all updates to it are managed by the callback, which takes
the same spinlock as the one taken by the lock code and released only by the
unlock routine. Combining this with (d) above, satisfies requirement (2).
Overall, since we use a spinlock (mentioned in (a)) to prevent CPU hotplug
operations from racing with br_write_lock-unlock, requirement (1) is also
taken care of.
By the way, it is to be noted that a CPU offline operation can actually run
in parallel with our lock-unlock sequence, because our callback doesn't react
to notifications earlier than CPU_DEAD (in order to maintain our bitmap
properly). And this means, since we use our own bitmap (which is stale, on
purpose) during the lock-unlock sequence, we could end up unlocking the
per-cpu lock of an offline CPU (because we had locked it earlier, when the
CPU was online), in order to satisfy requirement (2). But this is harmless,
though it looks a bit awkward.
Debugged-by: Cong Meng <mc@linux.vnet.ibm.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time/clocksource: Fix kernel-doc warnings
rtc: m41t80: Workaround broken alarm functionality
rtc: Expire alarms after the time is set.
* 'drm-intel-fixes' of git://people.freedesktop.org/~keithp/linux:
drm/i915/dp: Dither down to 6bpc if it makes the mode fit
drm/i915: enable semaphores on per-device defaults
drm/i915: don't set unpin_work if vblank_get fails
drm/i915: By default, enable RC6 on IVB and SNB when reasonable
iommu: Export intel_iommu_enabled to signal when iommu is in use
drm/i915/sdvo: Include LVDS panels for the IS_DIGITAL check
drm/i915: prevent division by zero when asking for chipset power
drm/i915: add PCH info to i915_capabilities
drm/i915: set the right SDVO transcoder for CPT
drm/i915: no-lvds quirk for ASUS AT5NM10T-I
drm/i915: Treat pre-gen4 backlight duty cycle value consistently
drm/i915: Hook up Ivybridge eDP
drm/i915: add multi-threaded forcewake support
Exactly like roundup_pow_of_two(1), the rounddown version was buggy for
the case of a compile-time constant '1' argument. Probably because it
originated from the same code, sharing history with the roundup version
from before the bugfix (for that one, see commit 1a06a52ee1: "Fix
roundup_pow_of_two(1)").
However, unlike the roundup version, the fix for rounddown is to just
remove the broken special case entirely. It's simply not needed - the
generic code
1UL << ilog2(n)
does the right thing for the constant '1' argment too. The only reason
roundup needed that special case was because rounding up does so by
subtracting one from the argument (and then adding one to the result)
causing the obvious problems with "ilog2(0)".
But rounddown doesn't do any of that, since ilog2() naturally truncates
(ie "rounds down") to the right rounded down value. And without the
ilog2(0) case, there's no reason for the special case that had the wrong
value.
tl;dr: rounddown_pow_of_two(1) should be 1, not 0.
Acked-by: Dmitry Torokhov <dtor@vmware.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
mmc: core: Fix deadlock when the CONFIG_MMC_UNSAFE_RESUME is not defined
mmc: sdhci-s3c: Remove old and misprototyped suspend operations
mmc: tmio: fix clock gating on platforms with a .set_pwr() method
mmc: sh_mmcif: fix clock gating on platforms with a .down_pwr() method
mmc: core: Fix typo at mmc_card_sleep
mmc: core: Fix power_off_notify during suspend
mmc: core: Fix setting power notify state variable for non-eMMC
mmc: core: Add quirk for long data read time
mmc: Add module.h include to sdhci-cns3xxx.c
mmc: mxcmmc: fix falling back to PIO
mmc: omap_hsmmc: DMA unmap only once in case of MMC error
