Commit 807f16d4db ("mtd: core: set some defaults when dev.parent is
set") attempted to provide some default settings for MTDs that
(a) assign the parent device and
(b) don't provide their own name or owner
However, this isn't a perfect drop-in replacement for the boilerplate
found in some drivers, because the MTD name is used by partition
parsers like cmdlinepart, but the name isn't set until add_mtd_device(),
after the parsing is completed. This means cmdlinepart sees a NULL name
and therefore will not work properly.
Fix this by moving the default name and owner assignment to be first in
the MTD registration process.
[Note: this does not fix all reported issues, particularly with NAND
drivers. Will require an additional fix for drivers/mtd/nand/]
Fixes: 807f16d4db ("mtd: core: set some defaults when dev.parent is set")
Reported-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Heiko Schocher <hs@denx.de>
Cc: Frans Klaver <fransklaver@gmail.com>
If partition parsers need to clean up their resources, we shouldn't
assume that all memory will fit in a single kmalloc() that the caller
can kfree(). We should allow the parser to provide a proper cleanup
routine.
Note that this means we need to keep a hold on the parser's module for a
bit longer, and release it later with mtd_part_parser_put().
Alongside this, define a default callback that we'll automatically use
if the parser doesn't provide one, so we can still retain the old
behavior.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
For some of the core partitioning code, it helps to keep info about the
parsed partition (and who parsed them) together in one place.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
The use of kmemdup() complicates the error handling a bit. We don't
actually need to allocate new memory, since this reference is treated as
const, and it is copied into new memory by the partition registration
code anyway. So remove it.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Merge second patch-bomb from Andrew Morton:
- most of the rest of MM
- procfs
- lib/ updates
- printk updates
- bitops infrastructure tweaks
- checkpatch updates
- nilfs2 update
- signals
- various other misc bits: coredump, seqfile, kexec, pidns, zlib, ipc,
dma-debug, dma-mapping, ...
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (102 commits)
ipc,msg: drop dst nil validation in copy_msg
include/linux/zutil.h: fix usage example of zlib_adler32()
panic: release stale console lock to always get the logbuf printed out
dma-debug: check nents in dma_sync_sg*
dma-mapping: tidy up dma_parms default handling
pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode
kexec: use file name as the output message prefix
fs, seqfile: always allow oom killer
seq_file: reuse string_escape_str()
fs/seq_file: use seq_* helpers in seq_hex_dump()
coredump: change zap_threads() and zap_process() to use for_each_thread()
coredump: ensure all coredumping tasks have SIGNAL_GROUP_COREDUMP
signal: remove jffs2_garbage_collect_thread()->allow_signal(SIGCONT)
signal: introduce kernel_signal_stop() to fix jffs2_garbage_collect_thread()
signal: turn dequeue_signal_lock() into kernel_dequeue_signal()
signals: kill block_all_signals() and unblock_all_signals()
nilfs2: fix gcc uninitialized-variable warnings in powerpc build
nilfs2: fix gcc unused-but-set-variable warnings
MAINTAINERS: nilfs2: add header file for tracing
nilfs2: add tracepoints for analyzing reading and writing metadata files
...
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts. They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve". __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".
Over time, callers had a requirement to not block when fallback options
were available. Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.
This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative. High priority users continue to use
__GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim. __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.
This patch then converts a number of sites
o __GFP_ATOMIC is used by callers that are high priority and have memory
pools for those requests. GFP_ATOMIC uses this flag.
o Callers that have a limited mempool to guarantee forward progress clear
__GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
into this category where kswapd will still be woken but atomic reserves
are not used as there is a one-entry mempool to guarantee progress.
o Callers that are checking if they are non-blocking should use the
helper gfpflags_allow_blocking() where possible. This is because
checking for __GFP_WAIT as was done historically now can trigger false
positives. Some exceptions like dm-crypt.c exist where the code intent
is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
flag manipulations.
o Callers that built their own GFP flags instead of starting with GFP_KERNEL
and friends now also need to specify __GFP_KSWAPD_RECLAIM.
The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.
The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL. They may
now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are multiple types of users of mtd->reboot_notifier.notifier_call:
(1) A while back, the cfi_cmdset_000{1,2} chip drivers implemented a
reboot notifier to (on a best effort basis) attempt to reset their flash
chips before rebooting.
(2) More recently, we implemented a common _reboot() hook so that MTD
drivers (particularly, NAND flash) could better halt I/O operations
without having to reimplement the same notifier boilerplate.
Currently, the WARN_ONCE() condition here was written to handle (2), but
at the same time it mis-diagnosed case (1) as an already-registered MTD.
Let's fix this by having the WARN_ONCE() condition better imitate the
condition that immediately follows it. (Wow, I don't know how I missed
that one.)
(Side note: Unfortunately, we can't yet combine the reboot notifier code
for (1) and (2) with a patch like [1], because some users of (1) also
use mtdconcat, and so the mtd_info struct from cfi_cmdset_000{1,2} won't
actually get registered with mtdcore, and therefore their reboot
notifier won't get registered.)
[1] http://patchwork.ozlabs.org/patch/417981/
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Jesper Nilsson <jespern@axis.com>
Cc: linux-cris-kernel@axis.com
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Due to wrong assumption in ofpart ofpart fails on Exynos on SPI chips
with no partitions because the subnode containing controller data
confuses the ofpart parser.
Thus compiling in ofpart support automatically fails probing any SPI NOR
flash without partitions on Exynos.
Compiling in a partitioning scheme should not cause probe of otherwise
valid device to fail.
Instead, let's do the following:
* try parsers until one succeeds
* if no parser succeeds, report the first error we saw
* even in the failure case, allow MTD to probe, with fallback
partitions or no partitions at all -- the master device will still be
registered
Issue report and comments initially by Michal Suchanek.
Reported-by: Michal Suchanek <hramrach@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
When CONFIG_MTD_PARTITIONED_MASTER=y, it is fatal to call
mtd_device_parse_register() twice on the same MTD, as we try to register
the same device/kobject multipile times.
When CONFIG_MTD_PARTITIONED_MASTER=n, calling
mtd_device_parse_register() is more of just a nuisance, as we can mostly
navigate around any conflicting actions.
But anyway, doing so is a Bad Thing (TM), and we should complain loudly
for any drivers that try to do this.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Since commit 3efe41be22 ("mtd: implement common reboot notifier
boilerplate"), we might try to register a reboot notifier for an MTD
that failed to register. Let's avoid this by making the error path
clearer.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
If a parent device is set, add_mtd_device() has enough knowledge to fill
in some sane default values for the module name and owner. Do so if they
aren't already set.
Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
add_mtd_device() has a comment suggesting that the caller should have
set dev.parent. This is required to have the parent device symlink show
up in sysfs, but not for proper operation of the mtd device itself.
Currently we have five drivers registering mtd devices during module
initialization, so they don't actually provide a parent device to link
to. That means we cannot WARN_ON() here, as it would trigger false
positives.
Make the comment a bit less firm in its assertion that dev.parent should
be set.
Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Use dev_pm_ops instead of the legacy suspend/resume callbacks for the MTD
class suspend and resume operations.
While we are at it slightly reorder things to avoid the need for forward
declarations.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
For many use cases, it helps to have a device node for the entire
MTD device as well as device nodes for the individual partitions.
For example, this allows querying the entire device's properties.
A common idiom is to create an additional partition which spans
over the whole device.
This patch makes a config option, CONFIG_MTD_PARTITIONED_MASTER,
which makes the master partition present even when the device is
partitioned. This isn't turned on by default since it presents
a backwards-incompatible device numbering.
The patch also makes the parent of a partition device be the master,
if the config flag is set, now that the master is a full device.
Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Pull MTD updates from Brian Norris:
"NAND:
- Add new Hisilicon NAND driver for Hip04
- Add default reboot handler, to ensure all outstanding erase
transactions complete in time
- jz4740: convert to use GPIO descriptor API
- Atmel: add support for sama5d4
- Change default bitflip threshold to 75% of correction strength
- Miscellaneous cleanups and bugfixes
SPI NOR:
- Freescale QuadSPI:
- Fix a few probe() and remove() issues
- Add a MAINTAINERS entry for this driver
- Tweak transfer size to increase read performance
- Add suspend/resume support
- Add Micron quad I/O support
- ST FSM SPI: miscellaneous fixes
JFFS2:
- gracefully handle corrupted 'offset' field found on flash
Other:
- bcm47xxpart: add tweaks for a few new devices
- mtdconcat: set return lengths properly for mtd_write_oob()
- map_ram: enable use with mtdoops
- maps: support fallback to ROM/UBI for write-protected NOR flash"
* tag 'for-linus-20150216' of git://git.infradead.org/linux-mtd: (46 commits)
mtd: hisilicon: && vs & typo
jffs2: fix handling of corrupted summary length
mtd: hisilicon: add device tree binding documentation
mtd: hisilicon: add a new NAND controller driver for hisilicon hip04 Soc
mtd: avoid registering reboot notifier twice
mtd: concat: set the return lengths properly
mtd: kconfig: replace PPC_OF with PPC
mtd: denali: remove unnecessary stubs
mtd: nand: remove redundant local variable
MAINTAINERS: add maintainer entry for FREESCALE QUAD SPI driver
mtd: fsl-quadspi: improve read performance by increase AHB transfer size
mtd: fsl-quadspi: Remove unnecessary 'map_failed' label
mtd: fsl-quadspi: Remove unneeded success/error messages
mtd: fsl-quadspi: Fix the error paths
mtd: nand: omap: drop condition with no effect
mtd: nand: jz4740: Convert to GPIO descriptor API
mtd: nand: Request strength instead of bytes for soft BCH
mtd: nand: default bitflip-reporting threshold to 75% of correction strength
mtd: atmel_nand: introduce a new compatible string for sama5d4 chip
mtd: atmel_nand: return max bitflips in all sectors in pmecc_correction()
...
Calling mtd_device_parse_register with the same mtd_info
(e.g. registering several partitions on a single device)
would add the same reboot notifier twice, causing an
infinte loop in notifier_chain_register during boot up.
Signed-off-by: Niklas Cassel <nks@flawful.org>
[Brian: add FIXME comments]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
The recently added mtd_mmap_capabilities can be used from loadable
modules, in particular romfs, but is not exported, so we get
ERROR: "mtd_mmap_capabilities" [fs/romfs/romfs.ko] undefined!
This adds the missing export.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: b4caecd480 ("fs: introduce f_op->mmap_capabilities for nommu mmap support")
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.
Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead. Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device. It also removes the need for
the mtd_inodefs filesystem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
cfi_cmdset_000{1,2}.c already implement their own reboot notifiers, and
we're going to add one for NAND. Let's put the boilerplate in one place.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Tested-by: Scott Branden <sbranden@broadcom.com>
MTD used to allow compiling out character device support. This was
dropped in the following commit, but some of the accompanying logic was
never dropped:
commit 660685d9d1
Author: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Date: Thu Mar 14 13:27:40 2013 +0200
mtd: merge mtdchar module with mtdcore
The weird logic was flagged by Coverity.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Brian Norris
Linus Torvalds
Mel Gorman
Frans Klaver
Johannes Thumshirn
Lars-Peter Clausen
Dan Ehrenberg
Niklas Cassel
Arnd Bergmann
Christoph Hellwig