UBI device numbers when attaching MTD devices by using the "mtd="
module parameter.
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Merge tag 'upstream-3.11-rc1' of git://git.infradead.org/linux-ubi
Pull ubi fixes from Artem Bityutskiy:
"A couple of fixes and clean-ups, allow for assigning user-defined UBI
device numbers when attaching MTD devices by using the "mtd=" module
parameter"
* tag 'upstream-3.11-rc1' of git://git.infradead.org/linux-ubi:
UBI: support ubi_num on mtd.ubi command line
UBI: fastmap break out of used PEB search
UBI: document UBI_IOCVOLUP better in user header
UBI: do not abort init when ubi.mtd devices cannot be found
UBI: drop redundant "UBI error" string
Calling kthread_run with a single name parameter causes it to be handled
as a format string. Many callers are passing potentially dynamic string
content, so use "%s" in those cases to avoid any potential accidents.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I want to be able to add UBI volumes with specific numbers, but the
command line API doesn't have that atm. Add an additional token to
support it.
Artem: amended the patch a little bit.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
The current ubi.mtd parsing logic will warn & continue on when attaching
the specified mtd device fails (for any reason). It doesn't however skip
things when the specified mtd device can't be opened.
This scenario can be hit in a couple of different ways such as:
- build NAND controller driver as a module
- build UBI into the kernel
- include ubi.mtd on the kernel command line
- boot the system
- MTD devices don't exist, so UBI init fails
This is problematic because failing init means the entire UBI layer is
unavailable until you reboot and modify the kernel command line. If
we just warn and continue on, /dev/ubi_ctrl is available for userland
to add UBI volumes on the fly once it loads the NAND driver.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
The ubi_err() macro automatically prefixes "UBI error" before the message.
By also using it here, we get a log like so:
UBI error: ubi_init: UBI error: cannot initialize UBI, error -19
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
ubi_debug_info struct was dynamically allocated which
is always suboptimal, for it tends to fragment memory
and make the code error-prone.
Fix this by embedding it in ubi_device struct.
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This kind of memcpy() is error-prone. Its replacement with a struct
assignment is prefered because it's type-safe and much easier to read.
Found by coccinelle. Hand patched and reviewed.
Tested by compilation only.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
identifier struct_name;
struct struct_name to;
struct struct_name from;
expression E;
@@
-memcpy(&(to), &(from), E);
+to = from;
// </smpl>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Use 'late_initcall()' in UBI to make sure it initializes after MTD drivers.
Signed-off-by: Jiang Lu <lu.jiang@windriver.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
UBI currently prints a lot of information when it mounts a volume, which
bothers some people. Make it less chatty - print only important information
by default.
Get rid of 'dbg_msg()' macro completely.
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Currently UBI fails in autoresize when it is in R/O mode (e.g., because the
underlying MTD device is R/O). This patch fixes the issue - we just skip
autoresize and print a warning.
Reported-by: Pali Rohár <pali.rohar@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch provides the possibility to adjust the "maximum expected number of
bad blocks per 1024 blocks" (max_beb_per1024) for each mtd device.
The majority of NAND devices have their max_beb_per1024 equal to 20, but
sometimes it's more.
Now, we can adjust that via a kernel parameter:
ubi.mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024]]
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
max_beb_per1024 shouldn't be negative, and a 0 value will be treated as
the default value. For the upper bound, 768/1024 should be enough.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch prepare the way for the addition of max_beb_per1024 module
parameter. There's no functional change.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
No functional changes here, just to prepare for next patch.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
On NAND flash devices, UBI reserves some physical erase blocks (PEB) for
bad block handling. Today, the number of reserved PEB can only be set as a
percentage of the total number of PEB in each MTD partition. For example, for a
NAND flash with 128KiB PEB, 2 MTD partition of 20MiB (mtd0) and 100MiB (mtd1)
and 2% reserved PEB:
- the UBI device on mtd0 will have 2 PEB reserved
- the UBI device on mtd1 will have 16 PEB reserved
The problem with this behaviour is that NAND flash manufacturers give a
minimum number of valid block (NVB) during the endurance life of the
device, e.g.:
Parameter Symbol Min Max Unit Notes
--------------------------------------------------------------
Valid block number NVB 1004 1024 Blocks 1
From this number we can deduce the maximum number of bad PEB that a device will
contain during its endurance life: a 128MiB NAND flash (1024 PEB) will not have
less than 20 bad blocks during the flash endurance life.
But the manufacturer doesn't tell where those bad block will appear. He doesn't
say either if they will be equally disposed on the whole device (and I'm pretty
sure they won't). So, according to the datasheets, we should reserve the
maximum number of bad PEB for each UBI device (worst case scenario: 20 bad
blocks appears on the smallest MTD partition).
So this patch make UBI use the whole MTD device size to calculate the maximum
bad expected eraseblocks.
The Kconfig option is in per1024 blocks, thus it can have a default value of 20
which is *very* common for NAND devices.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Introduce 'ubi->bad_peb_limit', which specifies an upper limit of PEBs
UBI expects to go bad. Currently, it is initialized to a fixed percentage
of total PEBs in the UBI device (configurable via CONFIG_MTD_UBI_BEB_LIMIT).
The 'bad_peb_limit' is intended to be used for calculating the amount of PEBs
UBI needs to reserve for bad eraseblock handling.
Artem: minor amendments.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Rename the 'attach_by_scanning()' function to 'ubi_attach()' and move it to
scan.c. Richard will plug his fastmap stuff there.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
We have a couple of initialization funcntionsn left which have "_scan" suffic -
rename them:
ubi_eba_init_scan() -> ubi_eba_init()
ubi_wl_init_scan() -> ubi_wl_init()
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch amends commentaries in scan.[ch] to match the new logic. Reminder -
we did the restructuring to prepare the code for adding the fastmap. This patch
also renames a couple of functions - it was too difficult to separate out that
change and I decided that it is not too bad to have it in the same patch with
commentaries changes.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
After re-naming the 'struct ubi_scan_info' we should adjust all variables
named 'si' to something else, because 'si' stands for "scanning info".
Let's rename it to 'ai' which stands for "attaching info" which is
a bit more consistent and has the same length, which makes re-naming easy.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Rename 'struct ubi_scan_info' to 'struct ubi_attach_info'. This is part
of the code re-structuring I am trying to do in order to add fastmap
in a more logical way. Fastmap can share a lot with scanning, including
the attach-time data structures, which all now have "scan" word in the
name. Let's get rid of this word.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Rename 'struct ubi_scan_leb' to 'struct ubi_ainf_leb'. This is part
of the code re-structuring I am trying to do in order to add fastmap
in a more logical way. Fastmap can share a lot with scanning, including
the attach-time data structures, which all now have "scan" word in the
name. Let's get rid of this word and use "ainf" instead which stands
for "attach information". It has the same length as "scan" so re-naming
is trivial.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
This patch removes the 'dbg_err()' macro and we now use 'ubi_err' instead.
The idea of 'dbg_err()' was to compile out some error message to make the
binary a bit smaller - but I think it was a bad idea.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Remove the pre-allocated 'peb_buf2' buffer because we do not really need it.
The only reason UBI has it is to check that the data were written correctly.
But we do not have to have 2 buffers for this and waste RAM - we can just
compare CRC checksums instead. This reduces UBI memory consumption.
Artem bityutskiy: massaged the patch and commit message
Signed-off-by: Josselin Costanzi <josselin.costanzi@mobile-devices.fr>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch introduces new 'mtd_can_have_bb()' helper function which checks
whether the flash can have bad eraseblocks. Then it changes all the
direct 'mtd->block_isbad' use cases with 'mtd_can_have_bb()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This patch fixes an oops in the error path of 'ubi_attach_mtd_dev()'. If
anything after 'uif_init()' fails, we get an oops in 'cancel_pending()'. The
reason is that 'uif_close()' drops the last reference count for 'ubi->dev' and
whole 'struct ubi_device' is freed. And then
'ubi_wl_close()'->'cancel_pending()' tries to access the 'ubi' pointer and
problems begin.
Note, in 'ubi_detach_mtd_dev()' function we get a device reference to
work-around this issue. Do the same in the error path of
'ubi_attach_mtd_dev()'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch introduces debugfs support to UBI. All the UBI stuff is kept in the
"ubi" debugfs directory, which contains per-UBI device "ubi/ubiX"
sub-directories, containing debugging files. This file also creates
"ubi/ubiX/chk_gen" and "ubi/ubiX/chk_io" knobs for switching general and I/O
extra checks on and off. And it removes the 'debug_chks' UBI module parameters.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* 'linux-next' of git://git.infradead.org/ubifs-2.6: (25 commits)
UBIFS: clean-up commentaries
UBIFS: save 128KiB or more RAM
UBIFS: allocate orphans scan buffer on demand
UBIFS: allocate lpt dump buffer on demand
UBIFS: allocate ltab checking buffer on demand
UBIFS: allocate scanning buffer on demand
UBIFS: allocate dump buffer on demand
UBIFS: do not check data crc by default
UBIFS: simplify UBIFS Kconfig menu
UBIFS: print max. index node size
UBIFS: handle allocation failures in UBIFS write path
UBIFS: use max_write_size during recovery
UBIFS: use max_write_size for write-buffers
UBIFS: introduce write-buffer size field
UBI: incorporate LEB offset information
UBIFS: incorporate maximum write size
UBI: provide LEB offset information
UBI: incorporate maximum write size
UBIFS: fix LEB number in printk
UBIFS: restrict world-writable debugfs files
...
Similarly to the debugging checks and message, make the test modes
be dynamically selected via the "debug_tsts" module parameter or
via the "/sys/module/ubi/parameters/debug_tsts" sysfs file. This
is consistent with UBIFS as well.
And now, since all the Kconfig knobs became dynamic, we can remove
the Kconfig.debug file completely.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch kills the 'ubi->dbg_peb_buf' debugging buffer and the
associated mutex, because all users of this buffer are now gone.
We are killing this buffer because we are going to switch to
dynamic debugging control, just like in UBIFS, which means that
CONFIG_MTD_UBI_DEBUG_PARANOID will be removed. In this case we'd
end up always allocating 'ubi->dbg_peb_buf', which is rather large
(128KiB or more), and this would be wasteful. Thus, we are just
killing it.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Incorporate MTD write buffer size into UBI device information
because UBIFS needs this field. UBI does not use it ATM, just
provides to upper layers in 'struct ubi_device_info'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
During scanning UBI allocates one struct ubi_scan_leb object for each PEB,
so it can end up allocating thousands of them. Use slab cache to reduce
memory consumption for these 48-byte objects, because currently used
'kmalloc()' ends up allocating 64 bytes per object, instead of 48.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Wrong macro was used in calculating the data offset: UBI_EC_HDR_SIZE instead of
UBI_VID_HDR_SIZE. The data offset should be VID header offset + VID header size
(aligned to the minimum I/O unit).
This was not a bug only because currently UBI_EC_HDR_SIZE and UBI_VID_HDR_SIZE
have the same value of 64 bytes.
Commit message was amended by Artem.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Currently UBI erases all corrupted eraseblocks, irrespectively of the nature
of corruption: corruption due to power cuts and non-power cut corruption.
The former case is OK, but the latter is not, because UBI may destroy
potentially important data.
With this patch, during scanning, when UBI hits a PEB with corrupted VID
header, it checks whether this PEB contains only 0xFF data. If yes, it is
safe to erase this PEB and it is put to the 'erase' list. If not, this may
be important data and it is better to avoid erasing this PEB. Instead,
UBI puts it to the corr list and moves out of the pool of available PEB.
IOW, UBI preserves this PEB.
Such corrupted PEB lessen the amount of available PEBs. So the more of them
we accumulate, the less PEBs are available. The maximum amount of non-power
cut corrupted PEBs is 8.
This patch is a response to UBIFS problem where reporter
(Matthew L. Creech <mlcreech@gmail.com>) observes that UBIFS index points
to an unmapped LEB. The theory is that corresponding PEB somehow got
corrupted and UBI wiped it. This patch (actually a series of patches)
tries to make sure such PEBs are preserved - this would make it is easier
to analyze the corruption.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Currently, when UBI attaches an MTD device and cannot reserve all 1% (by
default) of PEBs for bad eraseblocks handling, it prints a warning. However,
Matthew L. Creech <mlcreech@gmail.com> is not very happy to see this warning,
because he did reserve enough of PEB at the beginning, but with time some
PEBs became bad. The warning is not necessary in this case.
This patch makes UBI print the warning
o if this is a new image
o of this is used image and the amount of reserved PEBs is only 10% (or less)
of the size of the reserved PEB pool.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI can be built into the kernel or be compiled as a kernel module.
Further on the command line one can specify MTD devices to be attach to
UBI while loading. In the current implementation the UBI driver refuses
to load if one of the MTD devices cannot be attached.
Consider:
1) UBI compiled into the kernel and
2) a MTD device specified on the command line and
3) this MTD device contains bogus data (for whatever reason).
During init UBI tries to attach the MTD device is this fails the whole
UBI subsystem isn't initialized. Later the userspace cannot attach any
MTD to UBI because UBI isn't loaded.
This patch keeps the current behaviour: if UBI is compiled as a module
and a MTD device cannot be attached the UBI module cannot be loaded,
but changes it for the UBI-is-built-into-the-kernel usecase.
If UBI is builtin, a not attachable MTD device doen't stop UBI from
initializing. This slightly modifies the behaviour if multiple MTD
devices are specified on the command line. Now every MTD device is
probed and, if possible, attached, i.e. a faulty MTD device doesn't
stop the others from being attached.
Artem: tweaked the patch
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The UBI reboot notifier causes problems with hibernation. Move this
functionality into the low-level MTD driver instead.
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Passing the attribute to the low level IO functions allows all kinds
of cleanups, by sharing low level IO code without requiring
an own function for every piece of data.
Also drivers can extend the attributes with own data fields
and use that in the low level function.
This makes the class attributes the same as sysdev_class attributes
and plain attributes.
This will allow further cleanups in drivers.
Full tree sweep converting all users.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In the error path of 'ubi_attach_mtd_dev()' we have a tricky situation:
we have to release things differently depending on at which point
the failure happening. Namely, if @ubi->dev is not initialized, we have
to free everything ourselves. But if it was, we should not free the @ubi
object, because it will be freed in the 'dev_release()' function. And
we did not get this situation right.
This patch introduces additional argument to the 'uif_init()' function.
On exit, this argument indicates whether the final 'free(ubi)' will
happen in 'dev_release()' or not. So the caller always knows how to
properly release the resources.
Impact: all memory is now correctly released when UBI fails to attach
an MTD device.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch adds a capability to attach MTD devices by their character
device paths. For example, one can do:
$ modprobe ubi mtd=/dev/mtd0
to attach /dev/mtd0.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>