Commit Graph

76 Commits

Author SHA1 Message Date
Artem Bityutskiy fbd0107f4d UBI: amend comments after all the renamings
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>
2012-05-20 20:26:04 +03:00
Artem Bityutskiy 97d6104bac UBI: rename few functions for consistency
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-20 20:26:01 +03:00
Artem Bityutskiy e2986827d5 UBI: get rid of dbg_err
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>
2012-05-20 20:26:00 +03:00
Artem Bityutskiy 8056eb4ac4 UBI: clean-up terminology for self-checks in io.c
We have the "sefl-check" feature in UBI, but for historical reasons many
corresponding functions and commentaries in the code use term "paranoid check"
instead. Let's clean this up and use "self-check" everywhere.

This patch renames functions, amends comments and messages. It touches only the
io.c file.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-20 20:26:00 +03:00
Artem Bityutskiy aa44d1d35f UBI: remove Kconfig debugging option
This patch kills the UBI debugging Kconfig option completely and makes all the
debugging stuff to be always compiled-in. It was pain in the neck to maintain
this useless option because all users I am aware of have debugging enabled
anyway - how else will you diagnose errors otherwise?

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-20 20:26:00 +03:00
Artem Bityutskiy f01e2d1654 UBI: always warn if case of I/O errors
Currently UBI silently retries I/O operation in case of errors. This patch
makes it emit a warning before retrying. This should allow users notice issues
earlier.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-20 20:25:58 +03:00
Artem Bityutskiy a904e3f1de UBI: always dump VID and EC headers in case of errors
UBI (and UBIFS) are a bit over-engineered WRT debugging. The idea was to
link as few as possible when debugging is disabled, but the downside is
that most people produce bug reports which are difficult to understand.

Always dump the VID and EC headers' contents in case of errors when it
is helpful.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-20 20:25:58 +03:00
Artem Bityutskiy ef7088e7f8 UBI: always dump flash contents in case of errors
UBI (and UBIFS) are a bit over-engineered WRT debugging. The idea was to
link as few as possible when debugging is disabled, but the downside is
that most people produce bug reports which are difficult to understand.

Always dump the flash contents in case of errors, not only when debugging is
enabled.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
2012-05-20 20:25:58 +03:00
Artem Bityutskiy 25886a368d UBI: always dump the stack on error
UBI (and UBIFS) are a bit over-engineered WRT debugging. The idea was to
link as few as possible when debugging is disabled, but the downside is
that most people produce bug reports which are difficult to understand.

This patch weeds out the 'ubi_dbg_dump_stack()' function and turns it
into 'dump_stack()' - it is always useful to have stack dump in case of
an error.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
2012-05-20 20:25:58 +03:00
Artem Bityutskiy 0ca39d74de UBI: rename peb_buf1 to peb_buf
Now we have only one buffer so let's rename it to just 'peb_buf1'.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-03-09 09:39:31 +02:00
Artem Bityutskiy 5942ddbc50 mtd: introduce mtd_block_markbad interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:48 +00:00
Artem Bityutskiy 7086c19d07 mtd: introduce mtd_block_isbad interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:47 +00:00
Artem Bityutskiy eda95cbf75 mtd: introduce mtd_write interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:20 +00:00
Artem Bityutskiy 329ad399a9 mtd: introduce mtd_read interface
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-01-09 18:25:19 +00:00
Artem Bityutskiy 7e1f0dc055 mtd: introduce mtd_erase interface
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>
2012-01-09 18:25:11 +00:00
Brian Norris d57f40544a mtd: utilize `mtd_is_*()' functions
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-09-21 09:19:06 +03:00
Artem Bityutskiy 27a0f2a37a UBI: prepare debugging stuff to further debugfs conversion
We'll need the 'struct ubi_device *ubi' pointer in every debugging function (to
access the ->dbg field), so add this pointer to all the functions implementing
UBI debugging test modes like 'ubi_dbg_is_bitflip()' etc.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-06-01 11:21:52 +03:00
Artem Bityutskiy 2a734bb8d5 UBI: use debugfs for the extra checks knobs
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>
2011-06-01 11:21:47 +03:00
Artem Bityutskiy 1426414431 UBI: fix typo in a message
When a PEB passes the torture test, UBI prints
"do not mark it a bad", but should print "do not mark it as bad".
This patch corrects the typo.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-04-14 13:38:59 +03:00
Artem Bityutskiy feddbb34eb UBI: fix minor stylistic issues
Fix checkpatch.pl errors and warnings:

* space before tab
* line over 80 characters
* include linux/ioctl.h instead of asm/ioctl.h

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-04-14 11:34:41 +03:00
Artem Bityutskiy 3efe509070 UBI: check if we are in RO mode in the erase routine
'do_sync_erase()' has to check whether we are in R/O mode before
erasing the PEB. This patch adds the check and while on it, adds an
assertion which validates the 'pnum' argument, as well as removes
a check which is always true because it has already been done
few lines before.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-04-05 11:08:58 +03:00
Artem Bityutskiy 3d46b316bc UBI: use GFP_NOFS properly
This patch fixes a brown-paperbag bug which was introduced by me:
I used incorrect "GFP_KERNEL | GFP_NOFS" allocation flags to make
sure my allocations do not cause write-back. But the correct form
is "GFP_NOFS".

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-24 16:09:56 +02:00
Artem Bityutskiy 92d124f531 UBI: make self-checks dynamic
This patch adds a possibility to dynamically switch UBI self-checks
on and off, instead of toggling them compile-time from the configuration
menu. This is much more flexible, and consistent with UBIFS, and this
also simplifies UBI Kconfig menu and the code.

This patch introduces two levels of self-checks - general, which
includes all self-checks which are relatively fast, and I/O, which
includes write-verify checks and erase-verify checks, which are
relatively slow and involve flash I/O.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-16 13:50:16 +02:00
Artem Bityutskiy 6f9fdf62db UBI: remove UBI_IO_DEBUG macro
This additional little macro is used to print a bit more messages
while scanning the media. However, we have the 'dbg_bld()' macro
for this, so we better us 'dbg_bld()' and kill UBI_IO_DEBUG. This
simplifies the code a tiny bit.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-16 13:50:16 +02:00
Artem Bityutskiy 332873d60b UBI: allocate erase checking buffer on demand
Instead of using pre-allocated 'ubi->dbg_peb_buf' buffer in
'ubi_dbg_check_all_ff()', dynamically allocate it when needed. The
intend is to get rid of the pre-allocated 'ubi->dbg_peb_buf' buffer
completely. And the need for this arises because we want to change
to dynamic debugging control instead of compile-time control, i.e.,
we are going to kill the CONFIG_MTD_UBI_DEBUG_PARANOID Kconfig
option, which would mean that 'ubi->dbg_peb_buf' is always allocated,
which would be wasteful.

Thus, we are getting rid of 'ubi->dbg_peb_buf', and this is a
preparation for that.

signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-16 13:50:16 +02:00
Artem Bityutskiy a75867432a UBI: allocate write checking buffer on demand
Instead of using pre-allocated 'ubi->dbg_peb_buf' buffer in
'ubi_dbg_check_write()', dynamically allocate it when needed. The
intend is to get rid of the pre-allocated 'ubi->dbg_peb_buf' buffer
completely. And the need for this arises because we want to change
to dynamic debugging control instead of compile-time control, i.e.,
we are going to kill the CONFIG_MTD_UBI_DEBUG_PARANOID Kconfig
option, which would mean that 'ubi->dbg_peb_buf' is always allocated,
which would be wasteful.

Thus, we are getting rid of 'ubi->dbg_peb_buf', and this is a
preparation for that.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-16 13:50:16 +02:00
Artem Bityutskiy a87f29cbbc UBI: always re-read in case of read failures
When the read operation fails, UBI tries to re-read several times in
a hope that one of the subsequent reads may succeed. However, currently
UBI re-reads only if MTD failed to read all data, but does not re-reads
if all the data were read, but with an integrity error (-EBADMSB). This
patch makes UBI to always re-try reading.

This should be useful for reading NAND pages with unstable bits -
re-reading may help to get correct data.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-02-06 19:35:26 +02:00
Artem Bityutskiy 7950d023c5 UBI: use raw mtd read function in debugging code
This change affects only the debugging code. Namely, use mtd->read()
function instead of ubi_io_read() to avoid bit-flips injection
(ubi_dbg_is_bitflip()) which we do not want on the debugging path.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-02-06 19:18:58 +02:00
Artem Bityutskiy 276832d878 UBI: try to reveal buggy MTD drivers
When reading data from the flash, corrupt the buffer we are about to
read to. The idea is to fix the following possible situation:

1. The buffer contains data from previous operation, e.g., read from
   another PEB previously. The data looks like expected, e.g., if we
   just do not read anything and return - the caller would not
   notice this. E.g., if we are reading a VID header, the buffer may
   contain a valid VID header from another PEB.
2. The driver is buggy and returns use success or -EBADMSG or
   -EUCLEAN, but it does not actually put any data to the buffer.

This may confuse UBI or upper layers - they may think the buffer
contains valid data while in fact it is just old data.

Thus, try to reveal such buggy MTD drivers with simple debugging
code which fills the read buffer with 0x12 constant.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-02-06 19:18:32 +02:00
Artem Bityutskiy 2fff570e7c UBI: add a commentary about allocating VID header buffer on stack
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-01-26 10:14:23 +02:00
Holger Brunck d4c6381303 UBI: fix NOR erase preparation quirk
In 'nor_erase_prepare()' we want to make sure the UBI headers are
corrupted. But it is possible that one of the headers just contains
all 0xFFs, which is also OK, because UBI will erase it in case of
a power cut.

Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-01-26 10:13:52 +02:00
Artem Bityutskiy 7ac760c2f7 UBI: fix corrupted PEB detection for NOR flash
My new shiny code for corrupted PEB detection has NOR specific bug.
We tread PEB as corrupted and preserve it, if

1. EC header is OK.
2. VID header is corrupted.
3. data area is not "all 0xFFs"

In case of NOR we have 'nor_erase_prepare()' quirk, which invalidates
the headers before erasing the PEB. And we invalidate first the VID
header, and then the EC header. So if a power cut happens after we have
invalidated the VID header, but before we have invalidated the EC
header, we end up with a PEB which satisfies the above 3 conditions,
and the scanning code will treat it as corrupted, and will print
scary warnings, wrongly.

This patch fixes the issue by firt invalidating the EC header, then
invalidating the VID header. In case of power cut inbetween, we still
just lose the EC header, and UBI can deal with this situation gracefully.

Thanks to Anatolij Gustschin <agust@denx.de> for tracking this down.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reported-by: Anatolij Gustschin <agust@denx.de>
Tested-by: Anatolij Gustschin <agust@denx.de>
2010-12-03 15:49:21 +02:00
Artem Bityutskiy bb00e180a9 UBI: make check_pattern function non-static
This patch turns static function 'check_pattern()' into a non-static
'ubi_check_pattern()'. This is just a preparation for the chages which
are coming in the next patches.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-10-19 17:19:57 +03:00
Artem Bityutskiy 92e1a7d9e7 UBI: handle bit-flips when no header found
Currently UBI has one small flaw - when we read EC or VID header, but find only
0xFF bytes, we return UBI_IO_FF and do not report whether we had bit-flips or
not. In case of the VID header, the scanning code adds this PEB to the free list,
even though there were bit-flips.

Imagine the following situation: we start writing VID header to a PEB and have a
power cut, so the PEB becomes unstable. When we scan and read the PEB, we get
a bit-flip. Currently, UBI would just ignore this and treat the PEB as free. This
patch changes UBI behavior and now UBI will schedule this PEB for erasure.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-10-19 17:19:56 +03:00
Artem Bityutskiy 74d82d2660 UBI: remove duplicate IO error codes
The 'UBI_IO_PEB_EMPTY' and 'UBI_IO_PEB_FREE' are essentially the same
and mean that there are only 0xFF bytes instead of headers. Simplify
UBI a little by turning them into a single 'UBI_IO_FF' error code.

Also, stop maintaining commentaries in 'ubi_io_read_vid_hdr()' which are
almost identical to commentaries in 'ubi_io_read_ec_hdr()'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-10-19 17:19:56 +03:00
Artem Bityutskiy 756e1df1d2 UBI: rename IO error code
Rename UBI_IO_BAD_HDR_READ into UBI_IO_BAD_HDR_EBADMSG which is presumably more
self-documenting and readable. Indeed, the '_READ' suffix does not tell much and
even confuses, while '_EBADMSG' tells about uncorrectable ECC error, because we
use -EBADMSG all over the place to represent ECC errors.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-10-19 17:19:56 +03:00
Artem Bityutskiy f5d5b1f8c1 UBI: fix error message and compilation warnings
Fix the followong compilation warnings introduced by commit
095751a6e0838a712393a74eb0b7b6559dbdbe81:

drivers/mtd/ubi/scan.c: In function 'check_what_we_have':
drivers/mtd/ubi/scan.c:960: warning: passing argument 1 of 'get_random_bytes' discards qualifiers from pointer target type

Fix the following compilation warnings introduced by commit
1a49af2ca019dcb4614c32f832bbcb814b61409c:

drivers/mtd/ubi/io.c: In function 'ubi_io_read':
drivers/mtd/ubi/io.c:153: warning: initialization makes integer from pointer without a cast
drivers/mtd/ubi/io.c:170: warning: format '%s' expects type 'char *', but argument 5 has type 'int'
drivers/mtd/ubi/io.c:177: warning: format '%zd' expects type 'signed size_t', but argument 7 has type 'int'
drivers/mtd/ubi/io.c:177: warning: too many arguments for format

Also, amend the ECC error code string and add brackets and whitespace
there - this should make the message readable.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-06-14 08:47:49 +03:00
Artem Bityutskiy 1a49af2ca0 UBI: improve ECC error message
ECC errors are quite typical errors on NAND, so it is worth improving
the UBI message and print something like

ubi_io_read: error -74 (ECC error) while reading 4096 bytes from PEB 1:4 ...

rather than

ubi_io_read: error -74 while reading 4096 bytes from PEB 1:4 ...

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-06-11 17:23:37 +03:00
Artem Bityutskiy eb89580e1a UBI: introduce a new IO return code
This patch introduces the %UBI_IO_BAD_HDR_READ return code for
the I/O level function. We will use this code in order to distinguish
between "corrupted header possibly because this is non-ubi data" and
"corrupted header possibly because of real data corruption and ECC error".

So far this patch does not introduce any functional change, just a
preparation.

This patch is pased on a patch from
Sebastian Andrzej Siewior <sebastian@breakpoint.cc>

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reviewed-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
2010-06-04 11:30:42 +03:00
Artem Bityutskiy 786d783185 UBI: simplify IO error codes
We do not really need 2 separate error codes for indicating bad VID
and bad EC headers (UBI_IO_BAD_EC_HDR, UBI_IO_BAD_VID_HDR), it is
enough to have only one UBI_IO_BAD_HDR return code.

This patch does not introduce any functional change, only some
code simplification.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reviewed-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Tested-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
2010-06-04 11:30:42 +03:00
Shinya Kuribayashi be436f6238 UBI: misc comment fixes
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-05-07 08:33:32 +03:00
Shinya Kuribayashi 3f5026222e UBI: fix s/then/than/ typos
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-05-07 08:33:10 +03:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
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>
2010-03-30 22:02:32 +09:00
Artem Bityutskiy 6e9065d756 UBI: add write checking
Add an extra debugging check function which validates writes.
After every write it reads the data back, compares it with the
original data, and complains if they mismatch.

Useful for debugging. No-op if extra debugging checks are disabled.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-02-01 15:16:37 +02:00
Artem Bityutskiy adbf05e3ec UBI: simplify debugging return codes
UBI debugging functions were a little bit over-engineered and
returned more error codes than needed, and the callers had to
do useless checks. Simplify the return codes.

Impact: only debugging code is affected, which means that for
        non-developers this is a no-op patch.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-02-01 15:16:37 +02:00
Artem Bityutskiy de75c771b4 UBI: improve NOR flash erasure quirk
More testing of NOR flash against power cuts showed that sometimes
eraseblocks may be unwritable, and we cannot really invalidate
them before erasure. But in this case the eraseblock probably
contains garbage anyway, and we do not have to invalidate the
headers. This assumption might be not true, but this is at least
what I have observed. So if we cannot invalidate the headers,
we make sure that the PEB does not contain valid VID header.
If this is true, everything is fine, otherwise we panic.
2009-08-14 20:02:20 +03:00
Artem Bityutskiy 867996b15c UBI: introduce flash dump helper
Useful for debugging problems, compiled in only if UBI debugging
is enabled. This patch also makes the UBI writing function dump
the flash if it fails to write.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-08-14 20:02:20 +03:00
Artem Bityutskiy 5b289b562f UBI: amend NOR flash pre-erase quirk
In case of NOR flash, UBI zeroes EC and VID headers' magic,
in order to detect interrupted erasures. It first zeroes out
the EC magic, then VID magic. However, if a power cut happens
in between, we'll end up with a corrupted EC header and a valid
VID header, in which case UBI accepts the PEB, but prints a
warning. This patch makes sure we first zero out the VID
magic, then the EC magic, not vice versa. This is just a
small amendment to prevent warning messages.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-08-14 20:01:36 +03:00
Artem Bityutskiy 83c2099f5e UBI: fix compilation warnings
The recent "UBI: fix NOR flash recovery" introduced compilation
warnings which were immediately spotted by our linux-next keeper.
This patch fixes them.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-08 10:15:41 +03:00
Artem Bityutskiy ebf53f4213 UBI: fix NOR flash recovery
This commit fixes NOR flash recovery issues observed with Spansion
S29GL512N NOR.

When NOR erases, it first fills PEBs with zeroes, then sets all bytes
to 0xFF. Filling with zeroes starts from the end of the PEB. And when
power is cut, this results in PEBs containing correct EC and VID headers
but corrupted with zeros at the end. This confuses UBI and it mistakinly
accepts these PEBs and associate them with LEBs.

Fis this issue by zeroing EC and VID magics before erasing PEBs, to
make UBI later refuse zem.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-07-07 11:37:45 +03:00